Calculating capacity on my new battery

upnorthandpersonal said:

12.8V. Use the nominal voltage - 3.2V per cell for LiFePO4.

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nwredneck253 said:

the BMS said it held consistent 400 watts for 6 hours even and drained the battery 17%

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upnorthandpersonal said:

I thought the question was just along the lines of "I have a 100Ah LiFePO4 cell, how many Watt-hours?".

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MisterSandals said:

Ah yea, i see that now.
My mind started churning when i saw the 17% number...

not sure i would do it this way but here's the math:
230Ah x 12.8V = 2944Wh
2944Wh x .17 = 500Wh

and:
400 watts for 6 hours even and drained the battery 17%
400W x 6h = 2400Wh

2400 / 2944 = .81 (81% drained)

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nwredneck253 said:

drained then to 17

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nwredneck253 said:

i just built my first battery... i have 4 230ah eve cells.. i top balanced to 3.65 i have a DALY 150 amp 4 cell BMS........
the app seems very accurate on voltage and watts..... once it had it all activated i ran a small inverter with a hair dryer on low.... the BMS said it held consistent 400 watts for 6 hours even and drained the battery 17%

when i calculate total watt hours on the battery do i use 12v or 13v which is actual for the battery.......

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