Another Voltage question.....Lithium

[cricketo]

Originally Posted by bronsonj

FWIW, I bought the 58.8v lithium and 16.8v lithium aux battery for around $700 total (I can look up actual amount, but close enough for now). I figure spending more on the BMS than I spent on the battery didn't make much sense.

I totally agree with you, and I'm in the same boat. Salvaged Lithium cells are extremely attractive and the only way to convert LA EVs to Lithium that is economical.

I routinely check the cell variation and they all are staying within 0.01v thus far.

If you have the time and diligence to keep an eye on your pack (I know I can't do it), then likely you will be fine without a BMS. Just remember that making a mistake even one more time can have a very high cost.

So I do agree with you that a more expensive BMS would solve these issues. I haven't seen one that I consider to be a reasonable price yet so I give myself a buffer at the charge and discharge cutoffs.

Putting aside balancing, which often can be disabled altogether, the main thing is monitoring and charger/load cut off. As Sergio suggested, Zeva is plenty reputable and cost-effective solution.

I will add TinyBMS (which I'm currently trying to order, but the vendor is behaving strangely) and Batrium (mostly used for storage applications, but based on the functionality it is suitable for mobile).