LifePo4 charge current too low for 48V 80A system?

[heraclite]

I got my hands on (4) 12V 100ah LiFePo4 batteries. Originally, I planned to wire them in series and use a 48V 80A Growatt charge controller with (4) 310W 9.4A panels.

However, upon examining the battery spec sheet, I found that they are rated for a charge current of no more than 20A! For reference, a Battle Born 100ah is rated for 100A. I can't believe I didn't check that spec before ordering... But here I am.

Assuming I hang on to these batteries, does this mean I won't be able to do a 48V system without much slower charging? What if I instead wired the batteries for a 24V system in series/parallel and used a 24V Growatt controller? Would that work? What other options should I consider?

 

[John Frum]

80 amps * 48 volts * .85 conversion factor = 3260 ac watts.
That is the math.
A 100ah lifepo4 battery that is only rated for 20 amps sets off alarm bells.
How about a product link?

 

[gnubie]

Assuming I hang on to these batteries, does this mean I won't be able to do a 48V system without much slower charging? What if I instead wired the batteries for a 24V system in series/parallel and used a 24V Growatt controller? Would that work? What other options should I consider?

If the Growatt configuration is anything like the MPP's you can set your own charge rate. I'm not sure what effect this has on the solar side of the system, ie does that limit the system DC to 20A or just the battery charge current to 20A with any unused capacity being made available to the inverter for AC output. @snoobler has mentioned that it is the latter but I've not seen nor read anything that says that (not saying it's not true).

My own lifepo4 batteries have a recommended charge rate of 30A but will accept far more 100A without bursting into flame, but the trade off being a reduction in cycle life count. High amp charging increases cell temperature and that has consequences. Battleborn uses a heap of cylindrical cells instead of a few pouch cells. Given the passive nature of cooling prebuilt lifepo4 batteries that may give them an advantage in high charge current situations. If it was active cooling pouch cells win, no contest.

 

[heraclite]

I contacted the supplier, and it turns out there was a typo on the spec sheet. The actual rated charging current is 50a. Thanks.