12.8v 60ah 768wh Lifepo4 Battery - Needs BMS - $58/kWh

We already opened the lids of these batteries and confirmed all cells are balanced inside and the BMS is either locked or not working. If you replace the BMS the battery will work great. You can also buy multiple of these and put them in series then add one overall BMS. So if you bought 4, top balanced them, put them in series, and added a 16s BMS you'll have a great 48v 60ah battery at a great price. The balance lead wires are easily accessible and it should be very simple to add a BMS since all the connections are already there.

A few overseas battery manufacturers supply thousands of different private label brands. When it comes to batteries what matters most is how good they test. These have various brand names printed on them but they are all lifepo4 chemistry and structurally similar.

Fully charged - 14.6v
Fully discharged - 10v
A good rule of thumb for max amps is 0.5c charge (30a) and 1c discharge (60a).