Batteries to the Future | Fully Charged

welcome to a high-capacity cutting edge episode of fully charged it was a great privilege to visit the Department of Materials at the University of Oxford earlier this year I was shown around by Professor Peter Bruce who has spent the majority of his academic career developing the next generation of electricity storage systems I had a suspicion he might know some actual facts about batteries so there are basically two types of batteries you have a primary battery which is the sort of thing you buy put in your in your radio or something and then when it's finished you just throw it away or recycle it and then there's a secondary battery which is where which can store electricity so you can pump electricity into it chemical reactions take place inside the battery that store that electricity and then when you want the electricity back you can release it back from the battery to power whatever device you want those are the ones that perhaps are getting the most interest right now because those are the ones that really lie behind the you know the huge success of portable electronics such as the iPad or whatever and of course electric vehicles and will be important in storing renewable electricity on the grid and future as we move to more low-carbon electricity generation historically the most recent innovation in that is lithium-ion like am I correct in saying yeah absolutely lithium iron represented a huge breakthrough in the in the battery industry they would have to bear in mind there's no Moore's law in energy since one of the things I was going to ask you so we're not gonna double energy density store energy storage every 18 months in fact it's probably only increased 5 or 6 fold in in many decades and so the lithium-ion battery which more or less doubled energy density was a major breakthrough and was certainly one of the key drivers behind the portrait electronics revolution that we take for granted these days and it's because lithium-ion batteries have a higher energy storage energy density than alternative batteries in other words they store more energy per unit mass and per unit volume and that's for many applications that that's what matters there are many characteristics of a battery that matter energy density is one of the but you want to be able to charge it rapidly of course you want it to be last as long as possible you want it to be safe that's important so it's into flames absolutely you want it to be able to cycle many times so you can charge and discharge it many times and of course with a lot of consumer electronics products we often change the product before we change the battery because we want a new generation of whatever it is but when you move to things like electric vehicles and for grid scale storage even more then the economics say that you know you really need that battery to last a lot longer than a couple of years and that's one of the challenges that lithium ion batteries face how much lithium is there in a lithium ion battery so one of the first things that I think important is that there's no lithium metal in a lithium ion battery right so lithium many people are familiar with lithium throwing it into water and it fizzes that's lithium metal there is no lithium metal in a lithium ion battery the compounds contain lithium as one of the elements in those compounds I think the general consensus is that there isn't really a major problem that we can expect in terms of running in to a shortfall of lithium compounds to make lithium-ion batteries in fact it's probably at the current lithium-ion batteries in portable electronics use cobalt and cobalt is probably a more critical element in that sense in terms of cost certainly but know going forward in terms of the lithium batteries of the future I don't think we have to be too concerned about scarcity of course it's clearly important to recycle them and and and in some ways that becomes a little easier with the new markets of electric vehicles and grid scale storage because you would never consider just throwing those sort of things away you would always recover you know recycle vehicles and certainly recycle major plant the elements that go to make up these lithium batteries will be kept within the sort of sphere of their use recycle and reuse more in probably in the future than has been true in the past do you see a potential technology a variant of the technology we're using now that could increase energy density I think that we will see that it's but it's interesting because I think we have to remember that we've had the internal combustion engine for over 100 years and it didn't get to where it is now in five or six and we're really reinventing the powertrain and vehicles when you go to electric vehicles it's a real step change and it will take time to really reach an optimum level of performance and the battery undoubtedly is one of the most critical elements it's one of the real barriers to progress with electric vehicles and you're right although there are many things like how fast we can charge it and how long it will last probably the greatest of all a to two things safety and the range I think range anxiety is one of the issues and I think that that's why the plug-in hybrid actually offers a good at least interim situation because it it removes the anxiety issue but most of us commute no more than maybe 15 20 miles to work in India in Europe and so if you have a battery that will last that even that length of time or that that distance you could do most of the commutes on that and that would have a massive impact on reducing carbon emissions and still have the you know you can do the 300 400 miles driving exact very common for exactly but I would see that really as a stepping stone as we get as we see battery technology evolving and we will see new generations of batteries lithium arc batteries coming along that will give us longer longer range frankly in a lot of these storage challenges for electric vehicles and for the electricity grid in the future we don't really have energy storage technologies including batteries that are fit for purpose and the reason we don't have in many cases these technologies is that we still don't understand enough about the underlying science so we can go so far by optimizing on what we know and we can certainly improve technology and that's happened but you know to take that real step forward to get that battery that will last a lot longer before it has to be recharged for charge much faster in many senses we lack understanding of the underpinning science and if you think about it you know we've learned a lot about the natural world but we probably don't know far more than we know about the nature of life yes and and so things like energy storage come along probably thirty years ago we didn't really care too much about it they define problems that actually define areas of the natural world that we have to understand better and so it challenges us as scientists to explore the chemistry of the electrochemistry that goes on behind these devices and use try to use that knowledge to develop improve technologies new generations of lithium-ion batteries that will increase the range of electric vehicle it slide it so you're talking on micro I mean sub microscopic level super super yes and and it's partly because the major part of developing advances and lithium-ion batteries comes down to discovering new materials with new properties or combinations of properties and that is all about controlling at the atomistic level producing new compounds where you put atoms together in different combinations to produce different structures at the atomic level and then realizing by doing that materials that combine properties that we didn't perhaps have before so materials as I said that will store more lithium ions and that's what controls largely how much energy we can store in the device but do so perhaps with greater lithium ion mobility inside the sole so one of the things that controls how fast you can discharge and charge your battery is how fast these lithium ions these positively charged lithium atoms that zip in and out of the electrode as you charge and discharge how fast they move so you want them to move fast at the same time you want to get a lot of them in there because in a lithium ion battery you basically move lithium ions from one electrode to the other like any battery you have two electrodes a negative and a positive and an electrolyte in between and you move lithium ions from one to the other which you charge and back as your discharge so the more lithium ions you can stuff into these things the more charge the longer your you can drive here and the faster you can move them the faster you can recharge so that's a bit of a sort of broad simplification but it gives you a sense of that intimate interaction between the performance of your vehicle and actually what's really going down on at the atomistic level one of the key issues for electric vehicles is also cost you know lithium-ion batteries are too expensive yeah and the current lithium-ion battery that I have in my mobile phone uses cobalt in the positive electrode our core ball is expensive and that is reasonably acceptable for a product like that because it's a smaller small one you don't have a lot of material yeah but if you think about the size of a battery in a vehicle or even more if you think about grid scale storage where you have large large installations then it just becomes not viable with expensive elements now that therefore challenges us can we get materials that will perform as well as those materials based on cobalt but using for example iron or manganese iron and manganese no can you make electrodes from rust yes no no this is a very good run I mean one of the electrode materials that people are looking at we're looking at here is basically a lithium iron silicate so literally can you make electrodes from rust and sand in really low-cost materials now you also have to be able to process them at low cost and of course they have to have all the properties that you need but but you know these are the things that we now have to think about that perhaps a few years ago didn't really come into the aluminum because there's no no one-size-fits-all to the storage of electricity on the grid and I think energy storage as we're now seeing with increasing deployment of wind farms you know people are recognizing that the wind doesn't blow continuously solar doesn't help you at night storage is going to be not the only solution but part of the solution to making those you know clean grids those low-carbon grids work in the future Peter thank you so much go to camp pleasure thank you very much I then wandered down some corridors of the material science department looking for some PhD students who had some interesting projects so explain this then because those I recognize those cells in that yeah exactly so these are the same cells they're called 18 650 and that's because of their size they're 18 millimeters in diameter and 65 millimeters long and I don't know about the zero Chris isn't that explains I never knew why that number so there we go there we go yeah no I'm saying with that other cell that mean it's all those better science yeah so these are from old laptop batteries that Chris took apart and we we found through Chris's research that over half of the laptop batteries that we examined there are cells that are still usable meaning more than 60% of the capacity left and that's massive for small scale or even off the grid energy storage where you don't need like perfectly healthy cells yeah you just need something to be there but I mean and when you say that those those laptops then were considered finished wrong exactly yeah those were they were in the dump what we're going to do is harvest these useful cells and recombine them into useful small scale energy storage device designed for developing countries so this guy is our little demo unit that a Chris and the boys put together lights up are low low light is perfect so I can guarantee there's no wires secretly it's definitely working from that right can you kind of control the stress on those batteries by the software thereby lengthening their life further yes so yeah great question so for this uh if there won't be nearly as stressed as much as they are in a car as you're right like cars is going to like hammer them for LED lighting is very very low low power but on top of that what we're doing is our algorithms are detecting the state of health of each cell and then loading each cell proportional to its remaining capacity so then the weaker cells are getting like slightly less current and more healthy cells and that way they should degrade at the same rate and last longer and we're going to going to be extracting all of the energy storage capability out of every single cell fantastic guys No thank you very much so I've been really good and really I think it's fair to say important work that you're doing yeah will benefit a lot of people so congratulations and well done

Channel: Fully Charged Show

Views: 473,386

Rating: 4.8676844 out of 5

Keywords: electric cars, battery, Lithium-ion Battery (Battery Cell Type), Lithium Polymer Battery (Battery Cell Type), Oxford University, Materials Science (Field Of Study)

Id: RW1Xugey8j0

Length: 13min 23sec (803 seconds)

Published: Wed Oct 21 2015