Used Kokam SLPB125255255G1H 3.7v 85ah - $95/kWh

These batteries were recovered from battery packs that had a faulty BMS and were only in use for a few months. We tested a lot of these cells and they all tested above 90% capacity so you can expect great results. Every battery is solid and has good voltage. Most have insulators already on them which is recommended when building packs to use a separator in between the cells. The tabs stick out at least 1.25" so you have more than enough room to make connections. A lot of people use rivets or use a hole punch then connect with nuts and bolts. There is enough tab length to work with. We did not need to cut any tabs since the modules used bolted connections so you get the full tab. Most of these have a small hole on the tab where the busbar was bolted down to the tabs.

Always use a BMS when using power cells like this and also make sure your connections are secure and isolated so they don't short. These are true power cells so you don't want to short them out.

These cells also have a super high cycle life. These are not your standard type of lithium ion or polymer cell. This is one of the best out there.

The cells are rated for up to 3c (255a) charge and up to 8c (680a) discharge continuous. Of course you would have to use cooling and compression to run them high like that. For a solar storage project without any cooling we always recommend to stay at 0.5c for charge and 1c for discharge. So 42.5a charge and 85a discharge without cooling.

Energy density is excellent for a power cell at 181wh/kg.
Dimensions are roughly 10.5" x 10.5" x 0.5"
Weight 3.8lbs