Toyota Prius Gen2 Hybrid Battery - The 101 and DIY Cell Module Replacement

in this video we're going to be looking at replacing cells in a previous hybrid battery now this is a gen 2 pros hybrid battery but the principles will you know reflect at the hybrid vehicle batteries as well i'll also be talking about some of the parts on the hybrid battery how it sort of works in a very simplistic view about the bcm and things like that so follow along and let's learn something new if yours is still in the vehicle then i'll link in the description below a video where i actually removed the battery from the vehicle so you can follow that along and then your battery will be removed so you can work on it in the house or you know wherever is a nice environment for you to work on it so before i talk about the hybrid battery briefly we're just going to remove some 10 millimeter bolts any on the sides here right here right here there's two here and coming over on the back one here a little nut there a little nut there and there's none there so all the 10 millimeter bolts we're going to remove now and get this cover off so with all those bolts removed we can just take the cover and remove it and then we'll have something like this now again the purpose of this video is just to show you how to replace these cells here maybe your old cells are bad or you want to test them and then replace them with good cells but i will explain some of the things in here to make it less daunting so you can do this yourself i'll just talk briefly about how this battery pack actually works and what it consists of now this battery right here in front of us from the gen 2 prius is a giant 201.6 volt nimh which stands for nickel metal hydride battery so if you've ever used these before this is a rechargeable 1.5 volt battery again uh nimh nickel metal hydride and this is a very scaled down version of what you see right here the principles are exactly the same except that this one has temperature sensors it has a brake control module a lot of intelligence but really it's built around the same similar concept which is just one of these small rechargeable batteries right here so in this battery here there's 28 modules and each module is one of these silver rectangles here and they're connected in series now each module itself represents 7.2 volts of the overall voltage of the supply and when you multiply 7.2 by 28 because there's 28 of them you get the 201.6 volts so think of this as a giant 201.6 volt dc battery so we've talked about the modules and the voltage and whatnot let's talk about the capacity now this battery pack provides 6.5 amp hours and that's just a rating to tell you how much amperage a battery can provide for exactly one hour so this is 6500 mah or 6.5 amp hours and that's sort of how that is represented now each module here there's 28 of them internally within each module there's six individual 1.2 volt prismatic nimh cells inside you don't really need to know that but it's just a bit of information so you can understand exactly what you're doing when looking at these cells and how it works so coming over on this side of the battery pack now we've talked about the cells themselves let's talk about the bcm or um brake control module ecu which is this little uh silver box right here and the silver box here that's responsible for managing a number of things to do with these cells and the state of charge of them so in short if anything really goes wrong with this battery uh module here anything in here this is stored in the brake control module here and that can feed it back to the ecu of the car to tell you on your dashboard that there's something wrong in the hybrid battery itself so when you pull the codes for example with a special reader which works with this particular brand of car so in this case the gen 2 prius it can pull the codes from the bcm itself and it will tell you what's wrong with it it could be something like a temperature sensor's gone which is this thing right here and that reads the temperature of the battery pack so it could be a simple something as simple as that it could be a blocked airway it can't recirculate air and it's overheating it could be a dead module maybe module number 14. it really depends but this is responsible for storing errors such as this and other than storing errors and what not one of the most important features it keeps the state of charge of the actual cells which is around 40 to 80 percent uses a shallow cycle and if you're not familiar with cycling it's just a cycle for example you'll discharge your battery either by using it or whatnot and then you recharge it again and that's why it's called a rechargeable battery or rechargeable cell and when something is a shallow cycling this happens quite quickly and usually used in cases where you need a quick burst of power and so when this happens it's responsible for maintaining these cells and making sure they have a charge between 40 and 80 percent roughly something like that so now i've explained the modules and the bcm and how it all works it's a bit less daunting to work on because you understand it more so what we're going to do now is slowly remove these cells so one of the first things we're going to do is just pop off these end caps right here so get a small flat head something like this and just put pry it under here to lift this black thing off these orange tabs and the front will just pop off and when they're loose you can just pull it off and set it to the side we're going to do this for the whole trim so this one here this one here and the same again on the back so with all those removed we can just set them aside this piece right here it just flops down until we can actually remove it later so don't worry about that piece right there so if you have an impact gun i recommend pulling it out right now because we're going to remove all 56 nuts which actually link these battery modules together that's all these nuts here they're all eight millimeter every single one there's 28 on the front here and there's also 28 on the back we're gonna remove every single one eight millimeter so really quickly if you followed my last video we talked about a little security dongle here a safety dongle it was orange we pulled it out here and if you can see here you can follow these wires along here they go to these uh almost middle cells here so when you remove it here it makes the battery safer by disconnecting these cells from these cells making it safer to work on and that's why we did that when removing this battery so you can see now how that sort of works so with all the nuts removed now off the front and rear of the battery we can just pull these off they just come off real quick and now our modules are disconnected from each other so they're no longer in series so we're just going to do this on the front and the back of the battery so with those removed from the battery now so the modules are no longer connected in series we can actually access these here which are called bus bars and we can actually pop them out of their orange surrounding here we're going to pop every single one out and on the rear of the battery they're also present here they're just hiding behind a little terminal here so what you have to do is pop it out move the terminal out of the way and then we can access the bus bar we're just going to take them all out every single one and put them in here with our nuts because we're going to clean these up so now we have a jar here full of all of our bus bars which have corrosion on as well as all the nuts as well so two things you should always have in your kitchen vinegar baking soda baking soda great for heartburn cleaning um teeth anything like that but also cleaning kitchens as well as the white vinegar which acts as an acid and together they're going to actually clean our bus bars and nuts on this battery so we want two parts vinegar one part baking soda if you don't have baking soda vinegar usually works just as well and this is good for cleaning old coins and things like that you know it has endless uses these two things so we're just going to drop the baking soda in now so it doesn't have to be accurate just you know thereabouts i think that'll do it so you can see the carbon dioxide science is great isn't it so while that reaction is happening we're just going to set this to one side and work on the remainder of our battery so these bus bar cover assemblies here we can just move these to one side out of the way and that exposes ourselves a bit better to work on so now we're going to remove these vent tubes here which is connected to this white piece right here that's just in case any pressure ever builds up in these modules so there's a small hole connecting into here it can be vented away and out of the way so that's what it was originally designed to do and with that you can just sort of slowly pry it up and you can see it's plugged into each module here for that reason so a tip if you remove that quite fast it sounds like a piano a little random knowledge you really don't care about but there it is this here is a temperature sensor which is connected to these green wires so as i briefly mentioned before the brake control unit at the end over there reads the temperature of these modules and that's how it protects itself from overheating so with this we just insert a flat head underneath and then we can pop it out of this bracket right here with that removed there we can just unclip these plastic brackets here from the bar here just remove it and push it out of the way okay now there's two 10 millimeter nuts one right here coming over on the opposite corner over here there's also one just down there we're gonna take those two nuts off so the last thing i'm just gonna remove this little plastic piece right here and now we're gonna flip the whole battery pack upside down when turning upside down make sure these plastic parts here aren't sitting on top because this is quite heavy you don't want to be crushing anything like this make sure they're fully out of the way and that the weight is supported on as much as the frame as possible so with the battery pack flipped upside down you can see here that each module is actually bolted to the frame assembly itself so we will need to remove every single bolt here there's i believe 14 on each side making 28 so pretty much one per module there and just like the bus spa nuts they're also eight millimeter but these have a phillips head as well so with all those bolts removed on the underside now there's nothing holding the actual modules to the case so what we can do is just lift and push it out of the way pending a couple of temperature sensors underneath so the temperature sensors they just clipped onto a couple of modules here by one of these uh sort of like a spider clip so you just insert a flat head on the end here and it just hooks off so something like that and then it will just come right off and you can repeat that for the black one here and also the blue one on the end when reinstalling those afterwards just make sure they're spaced out how they were before so it can pick up a general reading from the whole area that's why they're spaced out so the sensors here as the bcm we talked about is responsible for reading center sensor readings it's only apt to that the harness here goes into the bcm so to remove this from the rest of the battery pack we can just remove that piece there and now we have our cells by themselves all the modules all 28 disconnected from all of that stuff there so now we can begin to replace these so i flip the battery pack back over so we can see the top side now and what we want to do is disconnect these compression blocks which are designed just to keep the modules together so we can start popping off the modules here before we do that we need to talk about polarity real quick which is something very important in dc circuits so i won't bore you with ac and dc circuits it's not really what we're here for we're just here to disassemble a hybrid battery uh dc circuits the current flows in one direction only and it can flow from negative to positive or positive to negative the difference being that's what your polarity is now if you notice at the end of these modules here this one's positive negative positive negative and they're all connected in series so it's important when we reassemble this that this corner here you can see a positive sign on this module right here that this remains here when we reassemble it with new modules or whatever you choose to do so the easiest way to do that is it to either remember it or just mark here that this one is a positive right here this one on this side is a negative and to be doubly safe which i'm sure there's no need to that way nothing can ever go wrong now we know the orientation of the modules and exactly how they should go back in according to the worlds of dc circuitry so with that done we're going to remove these four 12 millimeter bolts off the end right here so with the compression block off this side we can just pretty much remove the modules very easy and let's say how they come out they're not actually attached to the bars themselves they're just slotted in here and you can see if we look really closely there's a few plastic notches here that just helps keep them in line and that's as easy as that so one thing i'll mention well this battery pack here is from a gen 2 prius which is years 2004 to 2009 the individual modules here actually fit numerous hybrid cars so an incomplete list if you only want these then they're compatible with prius 2004 to 2015 toyota camry 07 to 16 nissan altima 07 to 11 lexus ct 200 and some others 2011 to 15 and yukon tahoe and escalade 08 to 13. so they actually fit a wide range of hybrid assemblies in all those vehicles so with the bus bars and nuts i'm just putting them in the bathtub so you can see a lot of that greenery there is the oxidization which is a byproduct of some of the copper here and you can see they've cleaned up quite nicely what you may need or may choose to do is just get a rag and rub off the rest of the residue if they don't come out as clean you can always give it another go or use less baking soda in the mixture baking powder and that way you can get them as clean as possible and with good conduction gives a good battery but there are compromises to be made if they're used so okay let's get back on with it so the longer really you leave them in the acidic vinegar solution the better they're gonna come out if you have something like a ultrasonic cleaner for jewelry you know that works great too but um i think this is a good compromise for our purposes let's continue so for those of you that are just replacing your cells you want to get on your way i'll leave you with some talk specs real quick now the bus bar nuts they're the ones in the vinegar right now 60 inch pounds when you put those back on the corner block bolts so the two diagonal ones we did here 90 inch pounds the 28 cell bolts which went on the underside of it 60 inch pounds and the 4 12 millimeter compression uh bolts on the side here 24 foot pounds that's all the torque specs i believe you'll need to put this back together and you can be on the way assembly is pretty much the reversal of disassembly remember to space out your temperature sensors and whatnot and get on your way now if for those of you want to stick around and learn a bit about cells and how to charge them reconditioning i'll just talk about that really quickly but the purpose of this video it's a disassembly video and so we'll get on with that for those of you sticking around you probably paid hundreds of dollars on these new modules here and you might be wondering oh well do my old modules have value can i recondition them can i get some sort of money for them well the short answer yes it depends now your old modules you could sell them as uh spares and repairs or something on ebay and someone can you know take a look and all that work is off your hands you know you can get some of the money you put on the new ones back on your old ones something like that if you want to dig deeper and see if these can actually be salvaged i'll talk about that real quickly so these modules here it's not like a lead acid battery in in a car where you can pop the top off top it off with distilled water and be on your way is very different once it's out the factory it's a closed system so how do you recondition these so usually to recondition these what mechanics would do that have the specialist equipment with these modules here that load them all up the machine would take in all the modules however many you have and they would charge them discharge them charge them discharge and take them through a cycle to try and recondition them once that's done they will load test them and what that is i'll explain momentarily now how do you know if one of these modules is good if you look to buy them on ebay what they do the sellers that is they'll just measure the voltage so you put a probe on each side of the module here positive and negative connect it to a multimeter and they'll say oh our modules measure at 7.8 volts uh our modules are 7.4 volts they're great but however a voltage a simple voltage like this is not a good guarantee that the module is fine however it's a good indicator of sorts but it's not a good guarantee and i'll talk about that um you know why that is so have you ever charged your phone to a hundred percent in a phone where it has a dying battery for example it will say a hundred percent however when you start using the phone which is i guess called a load test say you start recording a video you might notice your battery drops awfully quickly it might go to 80 70 60 when this within a space of two minutes and that's because you're actually putting a load on the battery of the dying phone so if you're using a bad battery it'll just decrease quite quickly and that's a test that guarantees you know how good a module is so this module might read 7.15 volts for example however when i start putting a load on this which could be a light it could be pretty much anything that runs on dc power then we have to see how quickly it drops in voltage and that is actually how we you know make sure that these are good and in a professional capacity they have machines that do this you load them all up it will put a load on them and tell you really quickly in a hobbyist way you know when you're doing it yourself at home you might want to connect a headlight bulb or something like that and then start a timer and that's how you would load test these so i will talk about how you can load test these if you you know curious you want to know how good your modules are maybe you want to sell them or whatnot it's really up to you now to charge these remember at the start of the video we talked about um these modules they're 7.2 volts each out of the factory the oem ones so we need a 7.2 volt charger now if you connect two of these together in series so here we have terminals on the end we can connect them in series and then the voltage doubles so if we have a 14.4 volt charger or 14 or something there about we can charge two of these together in series i have a laptop charger it's 21 volts right here so ac input dc output dc modules that's good for us so the dc output 21 volts now three of these together is 21.6 volts so this would charge three of them in series you know really well and that's all i have available if you have a hobby charger that can you know change voltage and whatnot that's exactly what you need but for people who don't then something like this would work quite well so with here talking about polarity which we touched on before you see that pin in there that would be either positive or negative and the outside shell here the case will be the um opposite so if the middle is negative the shower here would be positive or vice versa depending on the polarity and that's why they're separated by this yellow plastic so they don't touch each other so what you would do get a little crocodile clip and just tap that little pin in there and get another one around here and then you have your supply for charging three of these modules so that's an example how you could actually try and charge and discharge these at home and i neglected to mention uh when charging these i think a three amp charge is is okay a one amp charge is preferable i'd say a five amp charge is too much but it's really up to you and when i say discharge now that's a problem if you don't have a hobby charger that's capable of discharging things you'll just have to let it sit or put a load on it and try and discharge it that way so what you want to do when you're reconditioning these as i talked about you charge them discharge them charge them discharge them that's how you recondition this type of battery the ni mh battery now talking about load testing so once you've reconditioned it you've put a charge on it connect it to a multimeter so there's probes on each side here so we'll just put some alligator clips on the side and this goes into our multimeter here which we have set at dc volts 20 and it comes on at 7.15 volts so when load testing these open up excel spreadsheet create 28 rows one for each module record the starting voltage so this is after they're all charged up 7.15 now what we want to do is put a load on these so it could be a headlight bulb or something like that once you've put the load on so um pretty much just connect it to a headlight board that would be perfect something like that once you put the load on start a timer and then it's up to you how long you want that timer to run for you know the longer the better but it does take more time once you've chosen a time whether it's 30 minutes something like that record the ending voltage and this would be a suitable load test of something actually using these modules in action once you've done the exact same test for every single module with the starting voltage the ending voltage and everything in between you know exactly how the modules compare to each other so it's a good indicator of which ones are good and which ones are bad so in a very simplistic view with minimal equipment this is how you would do a load test at home so now we've talked about load testing you know how to make sure that these modules are actually good by attaching a load to them and also why a quick voltage reading is not a good indicator of the quality of a module and how to charge them and discharge them i will talk about one more thing which is called doctor prius now if you have a working prius your battery is connected you suspect a bad module or something like that so these are for people who actually have the working prius you can use um some software called doctor prius which runs on your phone it comes with a dongle that connects to the obd2 port which is under your dash and it can read the codes from the bcm which is this guy right here and it can actually read off real-time voltages from a pair of modules so two of them and this is a pretty good indicator of which modules do need replacing so it might be like um modules one and two you know they read a good voltage uh three and four they read good and again you can see all of them but if a couple of them a pair of them are a lot lower than the others in terms of voltage you can suspect these two to be quite bad so in which case you would only need to buy a couple modules and not necessarily a whole battery pack because what people do they'll try and upsell you and sell you a whole new thing when really you only might need two or four modules so i thought i would mention that for people who do have working priuses and you know can actually take um take advantage of this before taking everything apart and buying things they don't necessarily need okay so i appreciate that's a wealth of information but pause the video go back you know learn about dc voltages and whatnot to make it feel more you know native and comfortable to you but um again follow the start this video to replace your cells very easy to do it's just nuts and bolts all the tools i use in the video link in the description below and again if you didn't check out my battery removal process i'll link that in the description below so you can learn how to actually remove this from the vehicle it's quite heavy you know a good 80 90 pounds so be prepared for that but otherwise yeah that's the end of the video uh thanks for hanging in there if you stayed till the end and please like and subscribe it helps us a lot take care

Channel: TutorialGenius.com

Views: 97,907

Keywords: battery, battery cell, battery module, battery pack, cell, dead hybrid battery, diy, g9510-47020, g951047020, gen2, hybrid, hybrid battery, hybrid battery cell replacement, hybrid battery charger, hybrid battery maintenance, hybrid battery modules, hybrid battery reconditioning, hybrid battery repair, hybrid battery replacement, hybrid battery service, hybrid battery test, module, module replacement, prius, replacement, toyota, toyota prius battery

Id: 24rHayhOVZw

Length: 26min 15sec (1575 seconds)

Published: Wed Feb 16 2022