Used EV Car Batteries for E bikes, Trikes and Such???

[tmort]

I've been wondering if old batteries for electric cars, which run at much higher voltages, might at the end of their automotive life have enough power in them to use for some smaller EV. Maybe not a bike because the car batteries are bigger and too bulky for a bike. I was reading about Leaf batteries, they are made up of modules of lower voltages as well. So they might be smaller and still bulky for a bike, but for a trike or quad of some sort there might be room. I don't know what voltage those leaf modules run at, whether they are the full voltage for the whole pack or some lower voltage.

I know that a 48V lithium ebike battery when it is new and fully charged has about 56V or so and it still has about 30V when it is shut down by the BMS and/or controller on the bike. So you'd need to put the depleted modules or packs together in such a way that they would have enough and I suppose might need a different BMS or something else, but it seems there might be some pretty high capacity avaalable for scrap prices.

Maybe I'm dreaming. I don't have a need for this either, just wondering. There are lothers here who know way more than me.

 

[harrisonpatm]

I've been wondering if old batteries for electric cars, which run at much higher voltages, might at the end of their automotive life have enough power in them to use for some smaller EV. Maybe not a bike because the car batteries are bigger and too bulky for a bike. I was reading about Leaf batteries, they are made up of modules of lower voltages as well. So they might be smaller and still bulky for a bike, but for a trike or quad of some sort there might be room. I don't know what voltage those leaf modules run at, whether they are the full voltage for the whole pack or some lower voltage.

I know that a 48V lithium ebike battery when it is new and fully charged has about 56V or so and it still has about 30V when it is shut down by the BMS and/or controller on the bike. So you'd need to put the depleted modules or packs together in such a way that they would have enough and I suppose might need a different BMS or something else, but it seems there might be some pretty high capacity avaalable for scrap prices.

Maybe I'm dreaming. I don't have a need for this either, just wondering. There are lothers here who know way more than me.

Check out secondlifestorage.com for info more specific to the DIY applications of used EV. A general response to your question: since the cells are indeed large and bulky, one of the more popular uses for used EV batteries is stationary storage, where size and weight aren't as much of an issue. Sometimes it can be rather large scale; i can't find the article right now, but I do recall reading about a solar farm in I believe arizona that has a massive gigawatt-scale BESS made entirely of secondary Leaf cells. Pretty cool.

As for your question on Leaf cells in particular. Each "cell" that you see a picture of is actually 2 Lithium-ion cells in series, to make a nominal 7.4v per pack. Each generation of cells has different rated capacity, but for an example: gen 3 Leaf cells are rated at about 115aH when new. So when you get a used one, assume 80% capacity, 92ah. You mentioned 48v nominal battery, thats usually 14s. So 14 used gen 3 leaf cells at 80% capacity would would give you 48v nominal, 92ah, roughly 4.4kwh of storage. That's a rather massive amount of storage for a simple ebike, it lends itself more to e-motorcycle or something. Plus, you're looking at about 34 kilos. So yeah, repurposed EV batteries are more for electric motorcycles or even DIY electric cars, stationary solar storage, emergency backups, ect.

If you do go that route, used EV cells are nice in that if you find one for your application that fits your space and weight requirements, they are a breeze to put together in that you're usually using nuts, bolts and solid copper busbars, rather than messing around with cell holders and spot welders. They're also almost always rated for higher discharge per weight than 18650s or other smaller form factor cells.

Skip to 3:04 for a snapshot of a Royal Enfield with Leaf cells. I think the look of them looks nice too, all those neatly stacked rectangles.

Edit: after I posted, I can now see that the thumbnail for the video I liked shows an ebike with a nice slanted stack of Leaf cells, also nice looking in my opinion

 

[tmort]

I had just been thinking about it. I know someone with a trike and uses it to haul cargo and lives where there are big hills, etc. In general I was thinking of some sort of cargo type, likely made of steel micromobillity device, not so much a bike. The ones on the older style mini bike frames , stuffed in a Vespa and small motorcycle frames all look like pretty fun projects. Yeah, the bike with the stack of packs looks OK to me too.

 

[DogDipstick]

I have been running recycled, and new purchased EV packs for the last four or five years. They are the best, safest, most tested, longest lasting, strongest, and cheapest, battery you can buy. Many of us who have tried them know this and wont go back, ever. I have five or six friends online that I walked through their own bikes, motorcycles and four wheelers, and a few hundered followers who see what I do with the ebikes I build... and they all love them and know that they can make a Chevy Volt pack in half the weight and well over twice the power of a Molicell p42a pack of 2x the mass. I have bought 3000$+ of cells and made 6000$ + building packs out of them. I have cells from MANY cars i my garage. ONE of my Chevy cells is as powerful as a 10 cell stack of Molicell p42a. Laughs at 300A for years on end without detriment. Balanced to a T. Last one was a 5000w Super73. 52mph bike and... 60+ miles at 25mph~. Very powerful.

I promise you I will destroy any retail ebike pack in the world lol.. with my cost a quarter as much, lasts ten times longer, pack from the junkyard.

Look through some of my old posts or google my name. I straight up look for whole electric car batteries to buy. Have spent thousands in single purchases just to make powersports batteries with. I learned it from reading Spinning Magnets posts here.. to initially get into it here. Great oinfo here.They have been doing this for years here. There is no way a typical retail pack builder can match t6he sophistication and stringent standard of the EV car battery.

DO NOT google " Dog Lipstick". You have been warned.

 

[From-A-To-B]

^^^ what he said.

Yes, many of us have had a blast giving new life to EV batteries that are retired at the end of their life, a car crash, or overstock from the manufacturing line.

 

[DogDipstick]

Here it is.

A post that has spurred alot of ebikers, to look at recycling, as a viable option, for a good pack. Me included.

Salvaged EV cells index: Leaf, Volt, Tesla, Zero, etc

This is not a discussion thread, just add links that have details and/or pics. As more of these EVs are involved in wrecks, their battery packs are coming up for sale at surprisingly affordable prices. Cell dimensions (all in millimeters): Tesla-3, cylindrical 21700 (21mm X 70mm) Tesla-S...

endless-sphere.com

 

[amberwolf]

I've been wondering if old batteries for electric cars, which run at much higher voltages, might at the end of their automotive life have enough power in them to use for some smaller EV. Maybe not a bike because the car batteries are bigger and too bulky for a bike.

Yes, this is fairly common, as others above discuss. None of the ones I'm aware of are too big or bulky for a bike, once broken down to a usable voltage / etc module size.

The best part about using EV cells (even used ones) is that they are very likely to be very well matched to each other, from within a single pack (perhaps even across multiple packs), so they will all have the same properties as each other (capacity, internal resistance, etc), and thus will stay balanced to each other, making their full capacity always available (not generally true of the average ebike pack), even without a balancing BMS.
.
Regarding specific cells reused:

Tesla batteries have been broken down for the cells in them for a long time; IIRC Tumich has had a sale thread running for years. (though it's about differen cells now). There have been some other people selling the leftovers of their EV pack breakdowns that they used to build packs from, not sure if there are any still going at present.

Leaf batteries have been used for a number of builds; I think Chalo is still using them on his bike(s) at present (if it isn't Leaf, it's another EV pouch cell).

I've been using EIG EV cells for more than a decade for my bikes and trikes. (and those same "ancient" cells are still performing well for my usage). I don't even use a BMS, just check them periodically for balance (good so far) at different SoCs (full and empty).

Sites such as batteryhookup have had various EV (and other) batteries for sale, what they have varies over time, but there are quite a few good deals there.

I know someone with a trike and uses it to haul cargo and lives where there are big hills, etc.

I don't ride much on the hills around here, but I can go up the fairly steep North Mountain on 7th Street at 20mph, at least mostly unloaded, with the SB Cruiser cargo trike. (powered by those decade-old EIG EV cells)

 

[AdR]

I am all about re-using ev cells/modules.

 

[larsb]

They are the best, safest, most tested, longest lasting, strongest, and cheapest, battery you can buy. Many of us who have tried them know this and wont go back, ever.

Amen! Totally agree.

 

[spinningmagnets]

Go to the endless-sphere battery forum. Near the top is the battery section stickie thread index. Near the top of that is a list of EV cells, with pics and dimensions.

Salvaged EV cells index: Leaf, Volt, Tesla, Zero, etc

This is not a discussion thread, just add links that have details and/or pics. As more of these EVs are involved in wrecks, their battery packs are coming up for sale at surprisingly affordable prices. Cell dimensions (all in millimeters): Tesla-3, cylindrical 21700 (21mm X 70mm) Tesla-S...

endless-sphere.com

The king is LEAF modules, because they are such a nice package, plus they have threaded posts which are easy to connect into a pack. If those are too big, there are similar cells that smaller, but just not as famous.