G1 vs G2 Leaf batteries and what to verify from the seller

[somfas]

I plan to purchase Leaf batteries for my conversion. I need 10 modules for a 72V system. In prior threads I have seen a few people mention azlithium as a seller, and in general have seen suggestions to buy on ebay. I have an unreturned email into azlithium to see what they can offer (it seems like they are only selling complete systems with BMS and I have decided to go with Zeva for BMS and whatever they provide for a charger, if anything). However, techdirect has responded to me and they can sell me 10 G1 modules.

1) What are the pros and cons of gen 1 vs gen 2 Leaf modules?
2) I assume they won't be able to tell me what year car and what mileage these came from. What "proof" can I ask for that these are good batteries?

Thanks

[izzybird]

The only way to truly verify the condition of used batteries is to test them yourself or you are just going off their word. I have tired first gen modules and they still blow doors on lead batts just in cleanliness and weight savings, I wouldn’t be afraid of them. I believe 2016 and ‘17 30 kwhr modules were rumored to be degrading faster than anticipated, but I’ve also seen it argued that was just a software issue and updates fix the problem. My personal opinion on these used modules is to run them like the Nissan Leaf cab drivers do. Generally always charge to only 80%, usually discharge to only 50% or so, and quick charging in between. They seem to be having pretty good luck with them running hard all day every day. Unless you have the ability to pick and choose a matched set of modules out of a pile of them, your at the sellers mercy.
Or buy a wrecked leaf and have gobs of modules!

[bronsonj]

Sometimes the seller will tell you the capacity, but again that's just their word.

The issue with the early Nissan was a software issue where it over stressed the batteries and so they degraded more quickly. If the Nissan owner didn't fully charge and didn't let the batteries discharge too far then (as Izzy said) the cells will likely be fine. The damage for over charging and over discharging is cumulative and permanent. So it all depends on what their life was before they came to you and you won't have a clue about that unless you test them yourself.

I charge my lith cells to 4.12vpc and discharge to 3.25vpc. My parameters are more conservative than many on here but it should help my cells have a long happy life.

Good luck!

[somfas]

Thanks. So, just ask the capacity? They can accurately test that? And is that all the specs that would be important to get from the seller? Thanks again

[bronsonj]

Capacity *can* be tested, but you have to have a charger/discharger that will tell you the Amp Hours. The seller may not have a charger/discharger that is big enough to handle batteries like this.

Also, a 56 Ah battery tested from 4.2v to 2.5v has less capacity than a 56 Ah battery tested from 4.15v to 3.0v. I've seen it listed both ways on ebay. I've even seen some sellers guarantee at least 80% of original capacity... Meaning they don't have the charger and/or time to test and if you don't have the ability to test it you'll never know and the seller won't have to worry about giving refunds...

[somfas]

Thanks again bronsonj. I’m looking at some from azlithium and techdirect. $980 vs $610 for 10 modules. I feel like azlithium is the better choice but of course they are the most expensive.

[DaveTM]

I purchased my 7 module GEN-1 from azlithium. When they arrived UPS had dropped the package and one battery was damaged. Azlithium replaced it with no issues. I like my pack and I would buy from him again.

FWIW

[somfas]

Thanks DaveTM

[bronsonj]

When I bought my Chevy Volt cells I purchased some from GreenTechAuto and some from TechDirect.

GreenTechAuto was a bit sketchy... I had a couple phone calls with them and it was weird that the phone calls were answered just like it was some guy with a totaled Chevy Volt rather than a business.

TechDirect was a smooth transaction and I only communicated with them via email and had no problems.

I can't say how either would do with a UPS issue.

[izzybird]

That’s a pretty big price difference, I’d take the savings. They’re both peddling the same thing.