Wanting to build some Group24 lifepo4’s for mobility scooter

[HiddenEmailer]

Ive got a eagle mobility scooter on order it supports 2 x group24 12v batteries.

I figure I wanna go big or go home and I hear that you can get 200+ ah In a group 24 size, i’m a battery newbie though but I’m willing to learn.

What size cells do people recommend to use? Also what are good suppliers? to use I’m assuming it would be through AliExpress or Alibaba i’m in Canada but I do have a US mail box so if I had to I could get them down there that being said I assume all the cells come from China anyway so buying in North America just means paying a middleman that will cost me more so…

All that said I don’t have money to burn so I would prefer to go as affordable as reasonable but I don’t want to cheap out because I know there’s a lot of scammy crap on Ali.

Thanks

[Burgerman]

200 to 230Ah is possible.
Getting quality unused, grade A or EV rated cells is not easy. The chinese are a bunch of scammers and try everything. So that is the hard bit. I will let others offer recommendations.

[shirley_hkg]

https://www.wheelchairdriver.com/board/ ... 18#p193518

expresso's supplier seems genuine .

CATL cells are less risky.

[AgGuy]

I'm in the U.S., and had good luck here: https://www.amazon.com/gp/product/B099NMDL84/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&th=1
When I received the shipment, one cell was damaged in transit. They promptly sent a replacement. All cells were new and tested great.

[Qvickster]

US based seller. I have their 105 Ah EVE cells. Had zero issues and took 3 days to get to my door. https://www.18650batterystore.com/products/eve-lf105?sscid=41k6_6fjp0&

[UnicornBurner]

I just ordered the EVE 105ah from the same US seller. https://www.18650batterystore.com/products/eve-lf105
Our first conversion and keeping fingers crossed it all goes well. I will update if any problems or quality issues arise. Thanks to everyone for all the helpful input.

[Burgerman]

8 or 16?

[Qvickster]

I have 8 of their EVE 105AH cells and they are great. Had zero issues. I put them in a nf-22 chair and I get about 20 to 21 miles according to the chair. I usually only drive maybe 5 to 6 miles in a day.

[shirley_hkg]

I just ordered the EVE 105ah from the same US seller. .

Be very very careful with its 4mm thread terminal .

[snaker]

There is genuine distributor of EVE cells in VN. They sell both cells grade A and B. Cells B look identical as cells A. They are brand new, full capacity as cells A. The difference is that cells A have better C rating. And maybe their internal resistances are more equal. Cells A have a 2 years guarantee, one exchange one. Cells B are not guaranteed (but buyers can check and the seller will refund if the cells do not have full capacity). The price of cells A are about 60% higher than cells B. Actually an EVE 100Ah grade B costs $47, grade A costs $77. I think the same cell in the US will cost more than in VN. So the price $60 for a cell A is questionable.

I think cells B are Ok for powerchair as long as they are brand new and full capacity. Cells A are great if you could afford the price.

In VN the seller welds studs on EVE cells by a laser machine. The stud size looks big maybe M6 or M8.

[Qvickster]

I agree the 4mm screws seem super small when I was building my pack. I have been using it for about 1000 miles on this 400 pound chair and I haven't had a issue. I checked the terminals a few months ago and nothing was burnt or looked any different.

[Burgerman]

I think cells B are Ok for powerchair as long as they are brand new and full capacity. Cells A are great if you could afford the price.

I think that the B grade are much less suitable if you use a typical BMS and you would get issues balancing over time. But probably OK with a hobby type charger. But the 4mm thread in soft metal is a real issue.

Also while 100Ah lithium is better than the typical 60 or 75Ah lead. And can give almost double the range of lead. But that means high discharge levels (dangerously so) and high discharge rates (high C rates because same current and small Ah) and both of these things mean that you will likely get a few years rather than 10 to 15 years use. Plus fitting say 200+Ah of lithium not only lasts way longer, (lower average Depth of Discharge, it also offers not double the range of lead but 4x the range or better for those occasions you may want or need it. Or if you prefer 3.5x the range, and yet still has a safe cushion remaining to ensure good lifespan and protect the pack. I know 100Ah can work, is better than lead. But it is failing to take advantage of the huge lifespan/range that lifepo4 can give. It sort of partly misses the point on both counts. But if replacing 22nf you dont get as much choice. Because the chair is designed badly to begin with.

[HiddenEmailer]

But probably OK with a hobby type charger.

so... what types of chargers would be recommended for a larger pack (thinking or recreating expresso's pack)

[fishinjunky]

But probably OK with a hobby type charger.

so... what types of chargers would be recommended for a larger pack (thinking or recreating expresso's pack)

a used PL8 from shirley_hkg
https://www.wheelchairdriver.com/board/ ... f=2&t=6510

or a iCharger 4010 duo
https://www.progressiverc.com/products/ ... 0704167047
https://www.wheelchairdriver.com/board/ ... t=icharger