Silicon Anodes & Prelithiation for Fast Charge Batteries | Sun, Cushing & Kumar | StorageX Symposium

good morning california and good evening in china and asia time uh this is ichi i'm a faculty of material science engineering on behalf of my co-director of storage x initiated at stanford right here professor william chair i would like to welcome you back to our storage x symposium so this is a very exciting event we launched about half a year ago try to bring together all the better researchers to discuss exciting topics after 10 exciting events um in this event we are going to have an industry panel the previous 10 exciting event we were having academia to talk about cutting-edge research topic in this industry panel we will have exciting discussion about very promising materials on silicon but before i do that i would like to acknowledge our industry sponsors for storage x our industry members um over the past year giving us a lot of support both will and i and the whole team in storage x right here really like to thank the support from basf ciao way exxonmobil morata pge samsung share toyota and traffic girl today i also like to announce applied materials joining storage x to continue to support our effort in the symposium and also broadly in the research areas so with this initial introduction now let me move on to the panel and will and i prepare a very exciting panel to the audience around the world and they are the leaders in the areas of silicon and no and prolification we have three speakers for this panel a doctor kang sun who is the ceo of empress certainly taking the effort for the past decade to commercialize siliconangle the second speaker we are having is jim cushin from upi materials he is leading the effort of an apply to deposit lithium metal for multiple purposes including proliferation including as a thin lithium foil for lithium metal batteries the third speaker is suji kuma who has been leading a zin lab to develop silicon graphite angle with a lot of promise right there as well so with these three speakers each one of them will give us a 20 minutes presentation after their presentations will have a 45 minutes panel discussion i will welcome the audience to provide your questions through the q and a session and both will and i would like to moderate the q a session the panel session to really discuss have a deep dive on the silicon with that i would like to have dr kangsang from empress to kick off today's uh panel presentation please okay thanks e uh today my discussion here serves two purposes and the first is to introduce you some silic development and commercial products with that empties the second purpose is to share some of our thoughts how to effectively use a silicon anode in commercial product so the reason we are here is very obvious silly can display very high energy density compared to the con conventional graphite anode we are currently using however silicon has its own characteristics some of those properties are quite challenging make a silicon difficult as an annual material for hdmi on bathroom factory 1990s engineers scientists especially in japan had a start exploring the possibility in the silicon as animal material for lithium ion battery but many of those attempts were not very successful about 12 years ago professor ichi at stanford university proposed a concept i think even today is the most ideal silicon analog structure that is a silicon nanowire structure so amperes was a formed based on this concept from professor ichi sled today ampersand has two high energy density lithium ion lithium silicon anal technology platforms we have one is a 100 percent active silicon manual anal materials we also have a synthetic wifi and a platform so the the bose attempts with the highest capacity commercial analysts in industry today i have to emphasize the commercialized annual so amperes has a commercial as the highest energy density silica anal battery technologies now we have a battery technology from 320 watt per kilo for eva application to 400 watts per kilo for airspace applications now we developed the high capacity silicon and or ecosystem this is the part i'd like to emphasize in today's presentation without including many parts uh in the material though including silicon and itself matching cathode electrolytes predecession protocol binders formulations manufacturing process for silicon nanowire we have to make our own equipment yeah then the formation protocols cell designs all those are very important part of the silicon analysis in now this ecosystem maximizes the silicon angle performance very recently we demonstrated over 500 huawei per kilo silicon nanowire and or batteries and i would believe our road map today will lead to even higher uh performance now i like to share as much information and data as possible but i only have 20 minutes so i will go through this presentation fairly quickly if you have a question you always can can contact me at mps or contact professor etre at stanford university so this is our 100 active silicon nanowrist structure the structure build uh first we have this conductive filament is growed from the substrate now we call the silicon around the filament and produce the porous amorphous silicon structure of that we have a thin layer coated around the coating silicon so reduce the surface area so if you look at this from a cross section they look like a double sided carbon but those silicon noun were actually quite strong okay we can we can press it we can do the winding the stacking will not damage the silicone malware yeah so silicon nanowire has meaning our product has a micro and the macro porosity within the silicon nanowire we have a microprocessor between the silicon nanowire or her microplastic because of this unique structure so enable us to uh mitigate the silicon swell problem also because the silicon nanowire structure is not doesn't like it's very different from the silicon particle structure they don't interfere each other so gave us very stable uh anode now this is a the typical uh the discharge curve here you can see our silicon nanowire and our capacity is very close to theoretical limit here we can lift it to 34 000 million power per gram the picture on the right hand side is demonstrated the advantage of a silicon nanowire structure compared to the silicon graphite structure now this uh regular plot demonstrates how we modulate our silicon nanowire anal to achieve different performance and for different applications you see this red line here okay is a for give high energy the blue line we can achieve higher energy now we also have we can achieve the balanced power and the energy this is very unique recently we demonstrated 510 watt per kilo and potentially this prediction here we can achieve about 700 of the channel here now also look at this part and the silicon angle we designed here is agnostic to the cathode it doesn't measure we use lithium style we use and see silicon the graphite they are similar but they are different for years many people uh many companies try to associate into the industry without success and the long process that there are companies has been serving for 12 years without a success the reason is very simple okay because the industry most of the battery manufacturers i think just simply replace replace carbon machining then they can achieve better performance this other case i think those are two different type of materials just a fresh water fish and a saltwater fish you cannot put them together so cb can require very different evil system so at the end previous we designed a signal structure a long time ago but we spent years trying to find out what can the ecosystem make our silicon structure work yeah that including many aspects okay from elect from uh earth chemistry to the catholic to even to the human manufacturing process accreditation process formation protocols so the city can require different equality also require different manufacturing process so this is a charge that's silicon require different electrolyte electrical uh electrophysical electrochemical environments so years ago we couldn't figure out this so uh even we have a better silicon structure the best the silicon structure ideal silicon structure we couldn't make it work the last three years i've just designed a group of we call silicon electrolytes and they label us in superb performance you know here in this on the left hand side we are able to perform an ls 3d degree this is a problem needed for users and math this one initially electrolytes of electrolytes this wire line we use the regular electrolytes used in graphite products and blue line is redesigned for silicon so we added amperes because silicon and electrolytes that enable improve the cycle performance and the low swelling rate so our silicon structure is extremely important this is a silicon nanowire angle we just need a very minor change of our system network structure 3000 okay let me interrupt a little bit um looks like your you know connection is not stable i would like to propose uh the second speaker jim steppen to present first okay okay all right well sorry about the some of the troubles there but um first of all uh professor troy thank you very much for uh inviting us to be here today it's really an honor uh to have a chance to present here at the uh stanford storage x uh uh industrial panel uh let me just uh begin by speaking a little bit about applied materials applied materials is a actually a material engineering company we're most known for designing and building high volume manufacturing equipment for the cement semiconductor and display industries and i think when you look at uh you know some of these numbers on this page here the one that we're most proud of internally at least is our commitment to r d spending we spent over two billion dollars last year uh in fact if you look over the last decade we've historically always put in more than ten percent of revenue directly back into r d so we can continue to develop uh new uh really innovative solutions and bring those to uh the market but applied is more than just a semiconductor and display equipment company we actually have a division in germany which develops roll-through vacuum-based roll-to-roll equipment and in fact we are the world's leading supplier of this type of technology in the background in the picture here you can see some of these tools we can handle substrates that are up to four meters wide and processing at some incredible speeds up to 30 meters per second so this really supports this type of manufacturing supports a large number of different industries uh and for very very high volumes if we look at some of the types of processing we do with this roll to roll equipment we have platforms for thermal evaporation e-beam evaporation sputtering as well as cbd and i'm actually part of our cto organization our job in a cto group is to try to leverage some of the real strengths and capabilities we have at applied materials and look for new and adjacent markets where we might be able to use those capabilities and as we look at some of these new industries we're always trying to target inflection points somewhere where there's going to be a change and that change has an opportunity for applied materials to bring in a new solution particularly an enabling solution all of these industries here you can see have a lot of excitement going on right now and a number of key inflection points that we're looking at so what is the one inflection point that we're quite excited about right now in energy storage and that's really fast charge we really believe that fast charge is an absolute game changer when we're talking fast charge we're thinking about five minute charge something equivalent to what you would see today if you went to the gas station if we had that capability it would eliminate range anxiety i personally drive a 2013 nissan leaf i get about 70 miles of charge each day if i go to work and then i take my daughter to softball practice i have to drive home on the freeway no more than about 55 miles an hour to make sure i can get it all the way home and there are a couple days where i didn't quite make it so this range anxiety thing i know is real and i would sure love a fast charge solution besides addressing the issue with just anxiety there's a very big economic benefit to fast charge if you look at the trend these days with electric vehicles the battery packs are getting bigger and bigger and bigger so you always hear that the cost of batteries are going down but with larger and larger packs the overall cost isn't necessarily getting any cheaper for these electric vehicles if you look at nissan leafs today from the 70 miles that i get current models are about 150 to 220 miles you have the tesla model 3 the high end they're about 350 miles and then what really surprised me lucid motors has come out and announced a 517 mile per charge battery pack as you can imagine extremely expensive pack as soon as a fast charge is available and out there i think we'll immediately see the opposite trend people will go to smaller and smaller packs that will make this ev technology much more competitive with your traditional gas-based internal combustion engine and really accelerate adoption now when you combine fast charge with high energy density batteries uh we believe there's another enabling application and that is for the long-haul freight market i don't know if some of you might have seen a blog recently written by bill gates where he said electric vehicles are great but they're not going to work very well for the long-haul freight market because the batteries are just too heavy you have so many batteries for that it would be used that all of the weight would be used moving the batteries around instead of moving the actual freight uh so with high energy density batteries and we're looking about here about a thirty percent reduction in weight you're talking about thousands of pounds that you free up to actually move the load and make this an economically viable solution so what technology can enable fast charge if you look at kind of a standard industry roadmap of improvements in lithium-ion battery technology you'll typically see something like this with the current lithium-ion battery technology based on a graphite anode and then a next generation with you'll see the addition of silicon and that can either be 100 silicon as dr sun was talking about earlier today uh with ampris or some people are taking silicon and blending it or silicon or silicon oxide and blending it with graphite anywhere from 15 to 90 percent silicon in those cases and then the other technology we hear a lot about is solid state batteries of course that's always tends to be in the news these days but the technology that really lends itself best to fast charge is silicon and i'll talk a little bit today about some of the challenges of fast charge with graphite and then i'll talk about why silicon lends itself to be a very good solution for fast charge so how does silicon help enable fast charge first of all let's take a look at graphite what are some of the fundamental challenges with graphite and again dr sun mentioned earlier the low capacity that you get with graphite typical usable capacity in the 290 milliamp hour per gram range the downside there is when you're designing your battery you have to have a very thick electrode in order to get the capacity that you're looking for and the lithium ions literally lead to travel all the way through that thick electrode and it just effectively takes time one of the other side effects and particularly when you're discharging would because the lithium ion has to travel uh through longer distances that reduces the loading that you would design your battery to and that's typically in milliamp hours per centimeter squared we'll talk about where loading comes into effect a little bit later one of the second challenges with graphite is the slow intercalation rate uh the graphites uh graphite is typically in planes and so the lithium ions travel in effectively two dimensions in order to intercalate the problem is if you try to charge faster than the natural intercalation rate of graphite you will start to pile up lithium on the surface you will start to then plate lithium and you run the risk of getting dendrites that could short your anode and cathode the third fundamental challenge with graphite is the voltage itself of graphite is very near the plating potential of lithium another reason why it's very dangerous here and it's relatively easy to plate out and get those dendrites i have a little animation here to kind of show you uh what happens here so in a regular uh relatively slow charging rate your lithium ions will basically go from your cathode to your anode and then come on back and you'll notice that there are about six carbon atoms for every one lithium atom and that's why you end up having such a thick graphite anode in order to handle the capacity absorb the lithium if you try to go a little bit faster you run the risk of that lithium plating out on the surface you get a dendrite that shorts things go boom that's not a good thing so something that designers and batteries have to be very very careful about with graphite now with silicon or a silicon oxide first of all you have a much higher capacity and we typically look at usable capacity of silicon oxide in the 1200 range uh silicon in the 1600 range although some companies are seeing much higher numbers closer to theoretical i think actually amphibious with their very unique design there with their nanowire are getting some uh capacities much closer to theoretical than uh some of these uh more practical numbers um but this gives you the benefit of being able to design a much thinner electrode that reduces the diffusion length and diffusion time of lithium it also gives you an option to design with higher loading without compromising your charge and discharge rates second thing is the silicon actually alloys as opposed to intercalates and it's effectively a 3d kind of alloying reaction which in and of itself is much much much faster and the third thing is the voltage is a little bit different you're at about 400 millivolts uh and so you can charge up to about 70 80 percent very state of charge much faster without risking that plating effect so let's take a look at a quick animation here what happens when i try to fast charge now first thing that's interesting is the lithium will go will alloy with the silicon initially and then the slower graphite intercalation will typically happen and as you can see on the side you have four lithiums for every one silicon and that's why you get such a higher energy density with uh with the addition of lithium i'm sorry with the addition of silicon okay uh so that's great but you know nothing comes for free there are of course technical challenges that need to be addressed when you're uh putting silicon into your anode and one of the first ones people see is a silicon expansion effect or swelling um when silicon reacts with lithium it can expand up to 300 percent and this is something the battery designers need to take into account um dr sun showed you a picture of their silicon nanowire design and if you look at that carefully there's room there's some space in between each of those nanowires and that's a very impressive way to address this effect this swelling effect it's a very nice design other companies have addressed that other ways zen labs have talked a little bit about what they've done to address that swelling effect a little bit later cycle life is always critical especially with this expansion and swelling effect you can get degradation of some of the material and so cycle life is critical getting cycle life is critical for that reason you saw dr king also talk about the electrolytes and compatibility with silicon is very crucial otherwise you'll degradation in cycle life there as well so this is something that must be addressed uh in the device design and the materials used calendar life and you'll see some actually some data i think both from dr sun as well as from dr kumar from zen labs on cycle life calendar life 10 years again similar to cycle life needs to be addressed through device integration this is something that uh i think the injury industry is still working on getting to that full 10 year number i haven't seen data achieves that quite yet although dr kumar will talk about that and show some data on what they've achieved to date another challenge is this first cycle irreversible lithium loss and this is something that i will talk about in just a minute what happens is the first time lithium goes over the first time you charge up your battery not all the lithium that goes over comes back and on this graph here we can see where we charge up and then as we discharge we see about a forty percent up to a forty percent loss of lithium uh really defeats the whole purpose of adding silicon into your anode when you have this much loss but there are ways to overcome that and actually dr sun just started talking about pre-lithiation there before he got cut off so i'll talk a little bit more about that and uh explain what can be done to overcome this first cycle loss and then the last thing and this is critical for every any new battery technology you got to be cost competitive with graphite and we believe that we can actually achieve cost parity with the right solution of high volume manufacturing equipment and some taking advantage of some of the inherent uh capabilities of silicon to improve your cell design that can help get you a cost okay so let's take a quick a little animation at what's happening with this first cycle irreversible lithium loss so the lithium goes on over and when it does the first time you're forming an sci layer and you have some kind of dead and lost lithium that occurs in the bulk uh and depending on whether using silicon or silicon oxide and concentrations the amount of lithium you lose can change as i mentioned anywhere from one to about 40 percent and that's obviously a big challenge with the pre-lithiation process there's a number of different ways you can pre-lithiate your anode the method that we're using is just literally adding some excess lithium to these silicon graphite anodes so we have a lithium source and we're adding somewhere between two to about 10 microns worth of lithium to the anode and this is what the last one was a cartoon but this is actually a picture you're looking at a top view here on your left and a side view on your right this is a mixture of graphite particles with silicon particles and we have added a few microns of lithium to it the way that we do it it is a top-down kind of line of sight deposition process when we did this particular fib cut we did not have an environmental we did not have this in an environmentally controlled chamber so the lithium itself reacted but the nice thing is the lithium turned white so we can kind of see that contrast here of that lithium on the top and the graphite and the silicon beneath it now you don't want to have that lithium just sitting there on the top actually you want that lithium to react to uh alloy with the uh with the silicon and intercalate with the graphite and what's nice is when you add the electrolyte that will just naturally happen in literally in a matter of just minutes so there's no extra manufacturing process steps are needed just in that standard manufacturing flow you'll get this reaction to occur you'll actually form the sci layer there or start to form the sci layer on the anode and then when you go through your charge and discharge cycles you can achieve up to a hundred percent of the capacity back without any further loss uh in the capacity and what we're showing here this is some coin cell data that we've done at applied materials we made some devices without pre-lithiation and then some devices with pre-lithiation and in this particular case we had about a 20 percent loss without pre-lithiation but we were able to recover a hundred percent of that with the proliferation process we've done a large number of demos with uh um different uh battery manufacturers around the world and we're seeing that we can recover generally between 90 to 90 percent to 100 percent uh recovery with this prelitation process consistently in some cases we're actually able to get over a hundred percent which means we probably put too much lithium down there uh but it is possible um uh we see this is a very effective method to overcome uh that issue so when you're doing a process like this and you're trying to deposit a very thin amount of lithium in that 2 to 10 micron range it can be very challenging and some of the critical things that you want to see is that you can get a very good uniform film very smooth and you want it to be very high quality lithium what we're showing a picture of here is the deposition of lithium directly on copper um we're not this is not on a silicon graphite anode just because it's a lot easier to see uh the the lithium in this case and get a visual um cue on the quality of that film the smoothness uh the uniformity etc now when you're when you're processing lithium lithium is an extremely reactive material it can be flammable and at high temperatures is actually explosive with with uh with the water and so you have to be very very careful um as i mentioned earlier we use rule to roll equipment as vacuum based and so the lithium material is never exposed to the environment or to the people during processing uh the equipment as i mentioned earlier we can scale this equipment to greater than meter wide as needed uh for depending on the the size of the substrates that are used and if you run this at high speeds and you get very high efficiency of the lithium it can be a very cost effective solution as well so let me just kind of show you some some numbers here really quick we use the batpack model from argonne national labs to model out the cost of a traditional graphite uh based anode this is using nmc cathode and a loading of about three milliamp hours per centimeter squared and we're baselining that at 100 percent when we replace some of the graphite with a silicon oxide here for this model we used 30 silicon oxide keep the loading the same you have the benefits of less mass i talked earlier about that energy density uh gains you have so you have about 13 less mass 22 less volume but you're paying about a four to five percent premium for that which doesn't sound too bad uh considering the benefits that you have but we still hear from our customers no we want it to be at the same cost as graphite and here's where you have to take advantage of the nature of silicon and i made the comment earlier that you can increase the loading with silicon with the introduction of silicon and so going from three milliamp hours per centimeter squared you have the ability to go up to let's say four and a half milliamp hours per centimeter squared and at that loading you you actually use less inactive materials so you can use less separator material less copper less aluminum less electrolytes and so because of all the savings that you get there you can get to cost parity with graphite but you still have the benefits of fast charge uh increased uh energy gravimetric energy energy density volumetric energy density at that cost parity level now i'm always very skeptical of other people's cost models and i'm sure you can become skeptical of mine so one thing that we're doing uh we're working with argonne national labs their current backpack model actually does not have an extension for for silicon we had to do this ourselves but we're working with them uh actually through a doe grant uh eere grant to go ahead and update their model and then once they're done updating the model they'll make that available for everybody and that will allow each of you out there to run your own models and see how those costs work for you okay so you know in summary when we're looking at a comparison of a silicon and a silicon oxide anode to graphite we start comparing some of these key parameters and charge time energy density cost effectiveness scalability to high volume manufacturing and safety we do see that there are a number of benefits going to silicon there's still a little bit more work to do here to get this ready and scale to high volume manufacturing but we feel that the solutions are there the high volume manufacturing capability is there and we just need to see more proof in the performance especially in that cycle life and such okay we have a new way for you to to present i think justin have talked to you about uh let's move on to camp first so if you don't mind and you you go after ken okay sorry about the interruption so uh here i just uh quickly go through my slides this slide shows uh even a separator we have to select the special separator we actually customize the separator for our uh silicon or silicon or here okay particularly for silicon nanowire and on materials okay let's talk about this one so this is our application slides here this is a vertical uh take off drone material uh drones you can see the uh our annual performance in terms of read capability okay from c over five to all the way to three c this battery the 725 wow uh gave a 415 watt per kilo so uh all the the batteries are presented here are commercialized the batteries the customer orders not a lot of laboratory samples we also have a collaboration with usabc in eva battery design and the development this is a 60 ampere hour battery cycle data seo with series at a 30 degree this particular battery has a 450 watt per kilo and the 1200 watts per liter energy density this uh based on the information we have this is a about 50 percent higher specific energy than the best uv cells today okay this one uh also can charge to 80 capacity within 15 minutes so this is uh uh our production line this is the pylon and this small line yeah for silicon manure and so for silicon nanowire i know manufacturing process we don't have a powder mixing we don't have a slurry preparation we even don't have a coating okay no drying we don't need a catering we have a bare foot for you in and on the other side you have finished the silicone manure and so the picture in the bottom you can see this is the entire structure of this machine this is the first only the only row to roll the position equipment which gives precision 3d double-sided silicon manual growth fabrication capability now here we compare some our own products with the competitive technology which lithium metal okay in terms of energy density this probably uh the most competitive technology to silicon anal technology so on the left hand side is our silicon carbon silicon graphite composite angle performance in the middle is a lithium metal solid-state battery performance the information we collect okay on the layer on the right is our silicon nanowire and or battery performance now amperes has commercialized the silicon graphite compositor and or battery back to 2014. we started commercializing our silicon nanowire anal batteries in 2018 if you read the news it probably probably uh i know the airbus was our first customer those are the some customer designed batteries for various applications so our energy density from high 300s all the way to middle 400s so end of this year we will have a high 400 in terms of water per kilo battery ready next year we would uh we are planning to introduce 500 watt per kilo those are all not laboratory curiosities all those are commercial product with customer orders this is our road map okay we have very detailed road map but in this occasion i just uh presented this uh outline here so today uh we already achieved the 450 and we demonstrated the 500 but the 500 is not commercialized the product so next year we already promised our customer we will have 500 watt per kilo silicon manual or anal materials available for silicon graphite anal material we already produced a 350 watt per kilo commercial product for sale we're shooting for 380 watt per kilo next year for silicone graphite composite animal material we believe okay based on our model we believe in two or three years we should be able to reach about a 700 watt volcano okay this is a partially based on our silicon structure of electrochemical system and a partially based on the advancement of a new cathode materials now this just showed a few months ago we demonstrated the 510 wow per kilo in the lab we have planned to commercialize this material for uh select customers in 2021 currently uh mps has four operating companies we have amperes technology based on in fremont california focus on high energy density battery based on silicon nanowire and no technology we also have empress nanjing is making at developing and making silicon graphite anal material i'm presushi is our battery company a company produce battery cells recently we also have a pack capability then on the uh the new company we have it's called empress energy andreas energy uh is working on at this moment primarily working on electrical transportation we make a battery for marine vessels and electrical vehicles now we are planning to have energy storage business but we have not started yet yeah are we inviting the audience to be partner of mps we like to make our technology becomes a mainstream technology our product becomes a mainstream product we we need a lot of partners of course we need the customers we need the suppliers manufacturer tool manufacturing partners equipment manufacturing partners we also need the bankers and the investors to help us uh to be successful so this concludes my presentation the next page please uh before i finish okay i'd like to thank my colleague dr yunel stefan and dr michael wong they pro produce this data for me to make this presentation this is my contact information here you also can reach me and can reach professor e tree for additional information thank you very much well thank you ken uh i apologize for the technical issues now you manage to be able to present smoothly in the second part uh now let's move on to uh suji kumar suji are you ready please yes i am yeah good and again uh thanks a lot to stanford storage extreme for the invitation um the title of my talk is uh fast charging lithium-ion battery performance using silicon based anode yeah so just to briefly introduce our company um at zell labs our mission is to develop high energy fast charging and low-cost lithium-ion batteries for electric and aerial vehicles um we are based right here in fremont california and we have a cell prototyping center in joshing china where we make 10 amp power to 50 m power pouch cells for electric and aerial vehicles our technology is based on silicon based anode which can be paired with nickel rich cathode to achieve up to 400 watts per kilogram lithium ion cells and we're very proud to be working with the tier 1 customers in u.s in europe to bring our technology for commercialization and our business model is simple we would like to see our technology go everywhere and we want to license our technology manufacturing is very hard so we focus on technology development and we are a very eyepiece centric company with 40 issued patent this is the battery roadmap for electric vehicles published by lux research today conventional lithium ion battery they use nmc cathode and graphite based anode as previous two speakers talked about um advanced lithium ion will start to replace convinced lithium ion in the year 2025 and they will have a runaway for 10 years before solid state battery and lithium sulfur battery comes to market again you know if you look at solid state batteries uh you know the consumer electronics there um you know specs are not as challenging as automotive and they really care about high water per liter solid state has the highest water per liter but they do not meet all the other specs that's why when you go and buy your next smartphone it will still be powered by a graphite based anode more recently some of the companies have started adding uh you know 10 to 20 silicon to graphite to boost the energy but you know at least for next five years when you buy your next electric cars it will be powered by nmc cathode and a graphite based anode maybe five percent to ten percent silicon in a mixing graphite so we believe our silicon based anode will be a critical part of advanced lithium-ion solution and as dr kangson talked about silicon has two fundamental problems it has a very poor cycle life and a very high swelling we have solved these two problems and we have demonstrated thousand cycles uh meeting a key electric vehicle requirement we have a different approach and these are the set of solutions that we propose we do not use nano size we use micron size very low surface area uh you know silicon monoxide based anode we have our own proprietary electrode formulation using a very high strength binder that keeps silicon monoxide glued to the current collector a carbon nanotube network that adds sio expands contracts you know it still maintains uh electronic connectivity and jim talked about pre-lithiation so you know like all these there are lots of advantages of silicon monoxide it has one disadvantage that it has high irreversible capacity loss and that's where you know proliferation helps solve that and we also have our own proprietary electrolyte and then again we are riding on the same supply chain uh you know same graphite electrolyte supplier just giving them our formulation and our additives uh that helps improve cycle life the benefit is enormous you get four times more capacity than graphite and again we are not like going after 10 times capacity of graphite because uh we believe at four times of graphite we are providing significant advantage to our customers and we are able to meet all the specs not just few selective specs it gives you very high energy and also a very high fast charge jim talked about so i will not go into the details but one of the big advantage of silicon monoxide is it's low cost you know you could have very attractive technology for automakers if your cost is not below 100 per kilowatt hour they will not even talk to you you will keep wandering around in their r d department but if you really want to see your technology commercialized your cost will better be less than 100 per kilowatt hour and that's thanks for jim uh he shared all the cost model with deliveration that you know it can be easily integrated with the existing lithium ion batteries and the point i make is that silicon monoxide is sand you know it's present in every continent so the cost is rapidly coming down um you know the vendors we talked to in asia now there's several vendors not just one but multiple vendors some of them some of them have already scaled to 1000 tons a year and they are promising us that in few years the price of silicon oxide will be same as price of graphite so now think of that we are riding on the you know same chain of supply chain and we have a material with a cross parity with graphite but four times more capacity that's how we're bringing the cost down um you know what are the advantage of trilithiation is that of course you can compensate the irreversible capacity loss but you can also control anode potential so this is a three electrode cell study uh you know um with the reference electrode and uh you know we have electrode with no pre-lithiation and with different levels of so if you want to get a you know long cycle life you need to keep your anode potential below 0.74 and in our case we are keeping uh close to 0.5 volt so if you're below that you don't see you know poor cycle life or very high swelling and this is a picture of you know uh you know a lithium deposited on top of our silicon anode i want to share our swelling data this data is from one amp hour pouch cell which is not clamped it's a free standing and just you can put a meter to your gaze and you know monitor its thickness change and you fully charge and discharge the battery uh most you know like smartphone makers they want you your soiling to be below eight percent because if you have too much swelling it will pop up the device uh even graphite has three percent to four percent swelling we have managed to bring down to seven percent that you know from fully discharged battery to fully charged battery it goes up to seven percent and we continue to improve on swelling this is our road map with silicon anode uh today you know the pulsar leaders uh they use ncm 622 cathode and graphite based anode and you can achieve up to 240 watt per kilogram this is what you will see if you buy a chevy board you know the battery cell energy density is 240 watt per kilogram if we drop in you know our silicon anode in the same system we achieved 350 watt per kilogram and of course we had to do lots of technology solutions to make it go all the way to 1000 cycles that was the big challenge and we have 15 minute to 90 capacity uh now the trend is to keep making nickel rich so cathode from 60 nickel is becoming 80 percent nickel and you get more capacity uh so with a common cathode we can achieve up to 350 water per kilogram and here i want to make a point that we are not limited by the anode capacity i mean our electrode is already one-third the thickness of you know graphite based anode uh it's the cathode that needs to you know be improved upon um right now we can find a high capacity cathode so we are taking same 811 to high 4.3 volt but the issue that you know it you can only cycle 250 times so we have built batteries all the way from 315 watts per kilogram uh to 400 watt per kilogram and i will show data on this so we are very grateful to usabc award uh which will lead to commercialization of our ifv cells in our first program uh we built a 350 315 wattage kilogram battery with thousand cycles and fast charge and this was very successful and as soon as we completed this award we're very grateful we got the second contract where we are using 811 to qualify a 350 watt or kilogram battery but most importantly lower the cost like you know i mentioned automakers care a lot about the cost you cannot bring a solution uh that is very costly uh they will just you know like i said it will be an r d curiosity inside you know uh you know in the auto world but they will not commercialize your technology if you have a very high cost so that's why we are very much you know in the favor of silicon monoxide and we do believe that 75 dollars per kilowatt hour is challenging but possible and of course like the fast charge is a big benefit of silicon based channel and uh our last remaining challenge is calendar life and i will show some data based on that uh this is something we are very proud of uh it's a 12 amp hour pouch cell uh using 622 cathode and cell has been cycling at 100 depth of discharge going all the way to 4.3 volt and 2.5 volt at lower cut off it's a one hour charge and one hour discharge so some of these this data takes almost eight to nine months to collect if you do you know three hour charge three hour discharge so we're very proud of this data we think like we are the first one to put some of this data in public domain and most importantly you know as a part of the uscbc program we submit ourselves same set of cells that we tested it goes to national labs and they do a testing now in the previous data i showed you constant current constant voltage cycling auto guys they care about dst cycling it stands for dynamic stress test you can go to usabc website and it's a very complicated you know test profile which reflects the real life you know usage of electric car you know it will not be simple uh you know two-hour discharge or theoretical charge so uh our cells have been cycling at national labs under dht conditions and rpt is like a reference performance test each rpt is close to about 110 dst cycles so they reported 990 dst cycles uh this is the data from my first usbc program where we had some issues with the calendar live being tested at 30c 4c50c and some cells had to be removed because you know of like outgassing this is the charge rate test so you know like typically you charge battery for three hours to five hours that's what you know most of the electric cars do today but our lithium cells you know in 15 minutes it can be charged to 90 capacity in 10 minutes it can be charged to 80 percent of the capacity now why i'm using 15 because that's the goal of usabc so we work very closely with uscbc and you know our goals are to meet or exceed 80 percent you know at 15 minutes of charge again this is the verification of fast charge by national lab so again they are testing our 11.7 amp power cell and 50 m power pouch cell um so it's their comment that you know we achieved 90 percent they demonstrated 88 percent to 93 uh charge in 15 minutes now you also notice that they reported temperature rise because fast charge is a very dangerous condition for lithium ion cells it's very you know it's easy to do one time but can you do thousand times uh because it's a very degrading condition for the battery uh so like you know as you see at the bottom um the temperature rise is about 45 centigrade uh during fast charge condition and again we have demonstrated on both 11.7 m power cell and 50 amp power cell so you know like i was saying the fast charge condition degrades your battery you know like you are quickly charging quickly discharging so in this test we are doing a 4c charge a 15 minute charge and and we are discharging at one hour rate at every 50 cycles we are doing a capacity check you know this capacity check is at one hour charge and one-hour discharge rate and you know um we have we got about 750 cycles at the you know using the slope so that's something we're very proud of that you know like we have solved the battery degradation issues related to fast charge uh because you know even today the superchargers they won't let you charge thousand times uh they have the bms and you know they will you know stop you know fast charge once you exceed certain threshold number of you know fast charge cycles because it is really bad for the batteries but we are projecting 1000 fast charge cycles that's why our slogan is every charge fast charge and again this is the verification of our fast charging data by national labs you know like i said we submit ourselves as a part of the usabc program and right now the automakers gm ford chrysler they are very interested in understanding the consumer profile so they are starting at zero percent fast charge condition 25 percent fast charge condition and 100 fast charge condition so as you notice and the comment that you know if you have 100 fast charge condition um it's close to 17.7 fade uh you know it's the green line at the bottom and the yellow line is zero percent fast charge so now you know like the fast charge condition is degrading uh you know more than the zero percent but also i want to make a point that cells continue to cycle so right now i'm showing 763 dht fast charge cycles into actual real life you know automotive condition um the test is ongoing um this data is from our last month usabc meeting uh where we got this updated cycling uh based on this slope we think we will have 1000 fast charge cycles and that's our goal then also you notice that cells are being tested at 30 c 40 c 50 c to project a calendar life because you know these batteries need to have 10 years of calendar life and there's a model like you know you test for at least a year a minimum one year at different temperatures then you project what's your battery life so this is our last remaining challenge to solve the calendar life issues related to silicon based anode this is the thermal performance you know like they say your battery pack has to work in alaska and in arizona usabc aspects are at minus 20 degrees c to 52 degrees c and the specs is that you must have at least 70 percent of energy at minus 20 centigrade so we exceed that we have 73 of energy and this is where solid state batteries are measurable they barely work at room temperature and they cannot meet spec at minus 20 centigrade uh we're also working very closely with most of the evital makers because they care about high energy as well as high power you know as you can see in the hover mode they need very high power so during the liftoff they need high power for few minutes as they climb and then during the cruise mode they need high energy so that's where silicon anode has tremendous advantage uh you know it has fast charge capability uh it has a high power capability and uh you know and again during liftoff and landing it can provide very high power um so we are engaged with uh some of the leading players of evital and our technology can enable a 300 kilometer range ev tall and here the usable energy is very important so we can have a high energy of 350 400 450 but usual energy is defined where you meet the power numbers say for example uh when you know when you have this evital flowing for one hour and now your battery has depleted to 80 percent try getting high power when the battery has been depleted at 80 percent so no state of charge it's a very tough problem and that's where silicon anode shines that even when battery has been depleted close to 80 percent it can provide good power and of course the fast charge is very good because you know you have companies like uber elevate talking about air taxi and uh you know with the with the air taxi you know you need fast charge 10 minute charge 15 unit charge so that you can take off for the next flight um so we have a four underwater particular i'm still like i said uh we are cycling is limited by cathode not by the anode our anode can cycle thousand times and if you have to collaborate with the nickel rich cathode company uh who can stabilize it thousand times we can have an automotive cell that cycles thousand times at 400 watts per kilogram um finally commercialization require meeting all the specs and zerolabs is focused on delivering on all the specs unless we meet all the specs our technology cannot power automotive it's as simple as that you know most of the companies they highlight very high wattage per kilogram or very high water per liter but again you know today you can go and buy the next generation smartphone it will have 5g capability but if you open the lithium battery it is still powered by graphite anode why is that you know sony introduced lithium ion battery in 1991 30 years later still lithium ion cells use lithium global oxide and graphite same chemistry introduced by sony and these are very innovative trillion dollar companies uh they have all the resources in the world but they still use lithium carbon dioxide and graphite it's because of this slide they want you to meet every spec not just water per kilogram and water per liter so if you're a solid battery company you highlight your water per liter because that's where you shine you don't highlight your cost or you don't highlight your low temperature performance same thing a lithium sulfur battery company they would highlight 600 watt per kilogram but they will not talk about high temperature performance now even for transporting your battery you need to pass um 38.3 test which means you need to test your battery at 60 centigrade at least 10 cycles sulfur melting point is 115 centigrade and you need to test a fully charged battery at 60c you know like even when we talk to companies like one swing and dangler not just usabc even volkswagen wants to put your battery fully charged at 60c for 300 days so that's where it's not not every technology qualifies and unless you can deliver on all the specs you cannot put your technology on the road you know automotive is a very conservative industry and you know a battery recall can lead to billion dollars in losses so that's why it's important to meet all the specs if you dream to put your technology in electric cars so we understand the challenge uh we understand the difficulty and uh you know that's why we really believe in partnership with national labs who are keeping us honest who are testing our batteries giving us feedback and we are very grateful to the usabc um our final deliverable is you know um quarter two 2021 and we believe we will deliver a 350 watt or per kilogram beginning of life pouch cell and fast charge 15 minute we will demonstrate 1000 fast charge cycles every charge fast charge our last big challenge is calendar life we have to demonstrate 10 years and and of course the cost has to be below 100 per kilowatt hour and again we are working on the calendar life we already have very strong data on coin cells and you know single layer power cells uh we don't like to present data from single layer power cells because that's just research curiosity we love to present data on 50 amp ourselves and you know as a part of usabc we attend annual merit review and we like to put our data in public domain uh that's required for every doe award recipient so you will see lots of our data and annual merit review conference in washington dc and we feel that's the way to go very quickly i think i just want to thank uscbc and all the national labs and with this i conclude my talk thank you thank you thank you sujit uh let me uh invite all our panelists back to have a discussion kang and jim please come back to the stage i also invite my co-director professor william chair back to the stage it was really exciting um it's certainly silicon and now silicon related high energy and fast charging is the dearest topic to my heart you know 15 years ago i started to work on this topic i'm glad to see there's so much progress very exciting on the high energy as well as fast charging uh i'm going to let my co-director will to ask you the first question thank you for that really energetic set of talks i really enjoyed it no pun intended um maybe if i could i'll ask two set of questions please so today's talk had a major theme of taking silicon technology from lab to product but it's not finished yet and you all spoke about the challenges of scaling up whether it is in the cell size or in the manufacturing batch size so the first question i want to ask you is which scale jump do you think is the toughest one um maybe i can ask jim to take this one first perhaps from the manufacturing side which of these scale is the hardest leap to cross i'm not sure if that's a softball question or an impossible question for me one of the two um you know i applied is really all about scale um we you know uh mentioned we we build equipment for high volume manufacturing we don't build lab equipment we don't build r d equipment uh so you know everything we get into is really with that in mind um and uh for the you know the technology that we're talking about here if you look at um if you look at implementing a silicon and silicon oxide anodes there's two main steps uh there's the silicon itself replacing the graphite and tsuji talks a little bit about scaling up the silicon silicon oxide supply chain and then there's the additional step of pre-lithiation that we're working on we see a very clear path on the relations side i won't pretend like it's the easiest thing in the world but uh we think we have a very good approach in mind here we've got enough uh internal data that we feel very confident that is it can be scaled and we'll be ready uh you know at gigawatt scale uh very soon here congressman so i don't think manufacturing will be the challenge i think uh i'll let uh the other guys talk about the device scale up itself so go ahead please all right again you know like it's a very good question that how do you scale your technology to a large scale and in our skin in our case you know as a startup you know when you approach large automakers they're always skeptical you know hey how can a startup support a gigafactory so nice thing in our case is we can walk to any gigafactory and provide them our formulation silicon anode formulation we are riding on you know same supply of silicon monoxide but we need pre-lithiation so our partnership with applied is very critical that we need a large you know a capital equipment company like applied uh you know show interest in prelitiation and they can calm down automakers who are building their own gigafactory 10 gigahertz 10 gigawatt hour to 60 gigawatt hour so it really needs a scale of applied materials uh that can calm them down but it's a very good question that you know somebody needs to support this gigafactory and who will that be you know so from our side we need prelitiation we have our own role to roll proliferation in our own lab but that's not good enough for gigafactory we need help from company like applied materials thank you suji for us for silicon graphite i know i don't see any manufacturing scale up and the cost challenge and our prediction actually is a tripod appreciation we predicted the material first then we coded okay it is not a predicted electrode however for our silicon nanowire we the key is to make the how we can grow the silicon underwater at a relatively high speed all right so uh we have uh the the the equipment that i show you this is our first generation our second generation in design we believe okay we did we have to answer this to some very large companies in the next few weeks so uh we have been designing the second generation for some time this kobe 19 didn't help us so um we think at a gig what level okay even the silicon nanowire cut can achieve a single digit per ampere hour cost uh so uh the in terms of present uh predication we don't have large scale here you know we have been talking to a plant material as well but today we do have uh in-house continuous uh predication protocol as well thank you khan so it sounds like if i synthesize what all of you said is one of the key bottlenecks is going to be high volume manufacturing equipment which i think is good for you jim yes maybe this is a great segue to my my second question so academia has played a tremendous role in the commercialization of battery technologies of many kinds and and certainly for lithium-ion batteries we have some of our key innovators on the zoom call right here such as sam wintingham so the role of academia in spinning off and transferring technology to a commercial setting is absolutely very clear i was wondering if i can ask you to address the point of the role of academia in understanding the science of scaling up i think it's often understood that academia spins off the technology industry takes over to scale it up but i sense there's a number of key scientific questions that requires an academic focus and lens so i was wondering if you can talk about what might be some of the academic questions that could be answered that can in turn help the scale of challenges especially for example in high volume manufacturing would you like to go first i'll i'll jump in um as uh professor trey announced at the beginning of this session applied materials just joined the uh stanford storagex initiative and we did that because we recognized there are a lot of questions we still have about um about this technology and and about how to really optimize this technology um and how to take it to the next level um so you know we we talked a little bit about prolification i throw some nice little animations there where everything just works great in animation but fundamentally understanding exactly what's going on with the lithium when it's alloying and it's intercalating uh and how to form the optimal sei layer to get the best performance in cycle life in calendar life at different temperature ranges etc um uh those are very very difficult technical questions and that's part of why we joined uh the storage initiative um and we know there's a lot more work that needs to be done to understand that the fundamentals of what's going on here um i think when you take that forward we talked a little bit about solid state batteries uh and really understanding what's going on at the interfaces between the uh electrolytes especially a solid electrolyte a lithium metal all kinds of crazy reactions are going on there's a ton of work and understanding that still needs to be done and we definitely need the support of the great universities uh both in the u.s as well as around the world to better understand these things thank you jim akana i was wondering maybe you can offer us a few projects to work on do you have any exciting questions that you don't have bent with to answer on the science of scaling up uh we we do now we do actually we in addition to professor e3 we have uh quite a uh we have quite a few interactions with academic and locally okay in our around our factory around our research labs and one of the uh uh things we need uh uh we spent a lot of time to do simulation modeling is how far silicon and the graphite animal can go okay uh that's uh that that's the question uh we have been uh trying to uh to figure out yeah because we have not seen uh very comprehensive okay good performance of a silicon graphic and uh in commercial market today so that's that's the thing uh actually but on the other hand silicon nanowire anno is very clear to us okay there is a in terms of performance uh even the cycling today we're only 300 cycles we believe we can get a cycle we believe we can get energy density only thing we need to overcome is uh is the cost is the manufacturing scalability but for silicon graphene okay anything is not a hundred percent silicon how can we okay you mix those two materials together they behave totally different right their potential their electrical potential are different okay actually we have in terms of performance we have a lot more difficulty to handle the silicon graphite anode and the silicon manual so that's part we spend we work with two university managing to ask them to do some experiment to to do some exploration for us so academic uncertainty can get us guide us from a theoretical point of view okay that could save us a lot of energy at the time we may chase the ghost okay we want uh professor e3 and stanford university and other academic researchers give us some guidance okay so if i were to jump in so maybe you know at a small scale like we really baby our lithium ion cells you know and one of the critical thing is a solid electrolyte interface we don't understand it well but we are able to create a very strong aci so that something worries me that when you scale up when you are making you know one gigawatt or so lithium ion batteries every year when you are doing a very high speed prelitization uh are you able to maintain same strong sei now first of all we don't understand what the ci is in silicon based anode so how do we maintain at a high speed at high volume so that's something i believe academia like stanford or you know we have also collaborated with lvnl locally that maybe they can help us understand what the heck is this sei with silicon you know so we you know in our startup we screen hundreds of electrolyte additives hundreds of electrolyte formulation but we don't understand when it works why it works what exactly is on the ci and this bothers me all the time that what happens when we are doing at a very very high speed so that's something we believe that you know universities national labs can help us well suggesting that it's music to uh to our years i know that there are tons of questions that have been sent to us so maybe let me hand things back to e um and hopefully we will be able to go through some of it e yeah sounds good well i appreciate you guys uh bring the uh questions up right speaking of sci solar electronic interface uh i believe the the reason applied material joining stanford storage x one of them is we have a really powerful tool right here of cryogenic electron microscopy which allow us to stabilize sci and the liquid nitrogen temperature to study that carefully we'll have a lot more understanding down below we have a few papers already out there on the sci we'll have a lot more just to let you know so i want to ask the questions uh to let you know jim sujit and kang there are a lot of students and professors from academia from national labs listening to these uh storage action posts and probably a couple of thousands online in the zoom right here you don't see that many because we have another channel to broadcast so i think i bet everybody will be wondering about you know every year academia lab publishes so many papers on batteries and fundamental understanding of materials design and there's a lot of creative idea uh students and professor professors will be wondering what academia has been doing going to the industry like what you have nowadays what you demonstrate up to now so what's the lessons learned from an initial concept concept demonstration to today where you are what's the challenges right there can you share with academia lab to really guide us you know how to do this process better maybe i'll start from a suggested i don't know whether khan is still online looks like khan's connection might not be stable again he's in in china at this moment uh suji can you take this question first you know i think i answered partly but i will let's say defer this question to automakers right so when we go to automakers and when we say hey we have a high wattage kilogram and very high water per liter why are you not taking my technology and putting on the road and that's where they come back number one cost cost cost cost so i would request you know universities and national labs also focus on cost that hey can you do something to lower the battery cost because you might have very very attractive technology uh but if it is going to make the cost go up automakers are not listening so to me like that's one big thing um and then then secondly you know like i mentioned about meeting other specs and uh i and again to that i blame a lot to the financial venture capital community because they have they are using the metric of water per kilogram and water per liter to judge a technology or to fund a startup that's a very wrong way because you have to meet all the specs and and that's where i would say because see for let's say let's say project at stanford the studying calendar life of silicon it might not get funded because it is not sexy so so these are things that worries me that this is what the financial community has done to this that no just pushing a startup which is pushing the envelope of water per kilogram or water per liter but not focusing on other specs that you know automakers care about so i would request that get automakers involved ask them what they want and what will it take to take university research and commercialize it so we are somewhere in between as a startup we are very fast that we can take a technology from university put it into a product and showcase two automakers but it takes long years i will stop right there okay june any thought to share yeah and i would actually just kind of expand on on what sujit mentioned there when we looked at the semiconductor industry in the earlier days they did a pretty good job forming different consortiums that semitec was formed several other industry partnerships and alliances to establish standards and uh really put road maps together for what each next generation technology is going to look like and then the industry work like hell to deliver it um we don't have anything like that right now in the battery world and so everybody's off doing their own thing trying to solve some very very difficult problems uh and so you know i think this is really about how do we you know kind of get you know the industry somewhat focused on delivering uh uh some very key specific areas uh forming some partnerships potentially consortiums and such uh and really going at it uh to me you know we're very passionate about this idea of fast charge i think it is really enabling it will massively drive adoption of electric vehicles which is what we're all trying to do here uh but apply can't do it alone and prius zen labs can't do it alone stanford can't do it alone um uh as uh sushi just mentioned we have to do this in concert with uh the auto oems but they can't do it alone so uh how do we get you know a kind of a consortium together a real initiative together uh so we can uh uh address these challenges i think to me that's otherwise it's either not gonna happen or take a lot longer so jim just to let you know and suggesting can um stand for astrology x uh will and i are planning some major activity on fast charging it's a very exciting problem we noticed a lot of people in the audience from the battery related industry if you're interested in fast charging get in touch with will and me we we are really planning something uh big right now so so can i come to you about the question academia uh from the academia lab back to where you are right now and ambrose right what's the lessons learned and you can encourage academia to think about i think the uh we probably uh should cook the idea a little bit more on a bigger academic academic lab for example ulab is much better equipped to do research than the industrial lab okay once the idea is not a fully has not a fully uh investigate okay that this idea lend to the industrial lab actually is a delayed process okay the different lab has a different function you know your lab do preliminary research exploratory research much much effective than the startup lab this is not my first startup every startup i have it if i if someone handed me the idea okay uh the academic lab can perform it better you know we actually delayed the process okay so uh yeah i think that can i i really agree with you uh some of my students they want to form startup i often tell them i said you have a great idea you prove that you can publish your paper to form a startup have a commercial prototype you need to solve five ten maybe even more problem to have that prototype it's actually much harder uh that's exactly i think the what you are saying is uh and university lab we are very good and explore with huge resources so um with this question asked i want to hand back to my co-director will he is collecting also the questions from the uh the audience to to ask you thank you e so there are many questions um so let me try to maybe condense um some of the questions um so many of the questions has to do with the pre-lithiation jim you highlighted that quite a bit in congress can you give a sense of what is the time scale of proliferation yeah is that that for me sure go ahead jim yeah um so um the uh at least the again there are many different techniques that people are using um kong mentioned a powder technique uh there's a number of others our technique again is depositing a thin layer of lithium directly onto the anode we like that approach because we can control the amount of lithium very very well and we get a very high quality of lithium we start with battery grade and we're putting down battery grade or potentially something even even better the time scale is when we're running rolls and we're in meters per minute depending on how much but it can be anywhere from you know uh anywhere from five to uh 30 or 40 meters per minute to do that process [Music] and then as i mentioned with the to kind of activate that lithium you would just do that as part of the standard uh battery manufacturing process when you add the electrolyte so no additional time for that great jim um econ i'm curious is the prolification time the same for different silicon morphologies for the silicon we used to have two protocols for silicon graphite anal predecision one of them actually invented by one of these students okay that's liquid phase predication then our lab in nanjing and the event the solid uh uh predecession is much much faster the equipment is very cheap just a drone you put the particles in there you just you just rotate it as a drum for well then you produce it okay so that that part of i think we saw some efficiency caused after previously we have the way to make a slurry and we coat it we draw every cutting there okay we have a very high efficiency our efficiency i think i just i was in our landing level this morning our efficiency is 93.6 percent okay after previous issue now for silicon nanowire we used to use the contact okay predication that that certainly uh is not a mostly effective way to do it okay now we are transition ourselves uh to liquid phase predication thank you khan there was another related question on the role of inactive materials and prolifiation are there special considerations on the choice of binder when prolification is being considered and employed uh yes uh so maybe actually you know sujit i'm going to defer this to you you've done a lot of work on this actually uh i know you guys have developed uh so maybe you can talk first and then i'll add after you again you know like uh you know like in our case we use a different binder so you know today's most standard anode binder is cmc and svr used for graphite then you also use pvdf binder for cathode in our case we are using a special binder which is stable at higher temperature so it really helps preventation process so we did not design it for production we designed it so that it has high strength to keep silicon glued but it turns out it's also helping in the pre-listing process that our binder is stable at high temperature yeah so maybe i'll just comment on that um from our standpoint the we can control the temperature of our process in order to keep it below whatever the binder temperature is so we don't have to necessarily use a special binder however um if you have a binder that can go to higher temperatures that allows us to run at higher speeds uh you get more throughput get more output get a lower cost so from that standpoint uh we like um binders that can handle higher temperatures and that's why the binder that sujit has there is works very effectively for our process so let me ask and maybe start zooming out a bit since we're running out of time so it was a very interesting question on end of life considerations namely material recycling repurposing um the listener noted that it wasn't mentioned i think in cons and tsuji's comprehensive slides of all the things you have to hit so maybe i can ask some of you to take a moment and discuss your strategies and how important are you thinking about recycling and the like consideration at this moment and how does that play into your strategies yeah that that is a industry based on okay you can see the there are many companies uh they are doing this for living okay in our factory we have many described electors actually people coming to buy it okay people buy our waste water we don't have really waste to to uh twist okay all those waste material were purchased by other companies today including tesla is considering to have a recycle of batteries recycling factory business con you actually raised a very good point um even just the waste management and the environmental impact during manufacturing is also something that's not discussed enough um maybe we can expand the question um to include that aspect was not just the end of life of the battery but a scrap that's coming off the production line and environmental remediation for example um is silicon um offering some superior benefits in terms of environmental impacts are these considerations that you're looking into not in our factory and the silicon graph and the the pretty much the same of course the graphite is a third year okay because of the color but we handle them in the same way yeah so if i can add uh for us um you know we're not working at the whole battery level but for this pre-lithiation process i mentioned we use battery grade lithium and lithium is a very expensive component so we want to be extremely efficient in that use but any lithium that doesn't go directly onto the uh onto the anode we have to clean up uh but the nice thing is uh when we clean that up we can we're effectively forming a lithium hydroxide which is a precursor that goes into cathode manufacturing so we're not there yet but as we scale this technology up to gigawatt scale we certainly want to be able to take any of the unused lithium and be able to recycle that into effectively what could be used as a precursor by our customers for cathode manufacturing thanks you know i'll you know be very brief i think this is a silicon anode panel but i don't want to pass the bug but you really have to focus on cathode uh you know the 70 cost of a lithium ion battery is materials and the costliest component is cathode that's where you have you know all the precious metal lithium nickel cobalt manganese and you want to make sure that those metals gets recycled so i i really don't want to pass the bug but i think that's the you know biggest problem and i hope you will have a cathode panel and i hope you'll answer this question what's your plan to recycle all these metals you're reading our mind sushi um we are a bit past time so maybe let me um before i hand things back to e let me put in a big pluck uh from my colleague professor inez azaveto so she as part of our storagex initiative is investigating the co2 footprint of battery manufacturing really thinking about and comparing various manufacturing methods and understanding the co2 impact i think this is often not discussed and this is something that i think we are very interested at the systems level so thank you very much e yeah well i i would like to thank the three panelists like kang suji and jim for your insight we could go on for another hour or two there are many good questions in my mind and other in audience mind as well so i guess we need we need to stop and let can go to sleep and some of us to start the day so let me end this uh uh you know this panel by having the last slide um [Music] so i want to advertise our next event is on october 2nd the same time storage x x stands for you know everything connected with energy storage so next one we are going to expand our horizon a little bit having x equals to field we have two world experts to join us professor socina hailey from northwestern university and tom haramiro his professor here at stanford to talk about x equals to field i look forward to seeing everybody in the next event bye now

Channel: Stanford ENERGY

Views: 3,423

Rating: 4.9259257 out of 5

Keywords: Stanford, Stanford Energy

Id: S5P6SUW4pnc

Length: 106min 9sec (6369 seconds)

Published: Mon Nov 02 2020