Battery Rating vs Capacity Monitoring
Some things: Shipping batteries in the US requires the Watt-Hour rating to be marked on the battery, and the rule is to use the "nominal" voltage. So LFP uses their 12.8v figure for that 100AH x ...
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Because the voltages are different - the LiFePO4 provides more energy (Wh) than the AGM which provides more energy than the FLA.
If you pull 90Ah out, your are at 10% SOC in terms of Ah, but you are actually at 8-9% SOC in terms of Wh.
A battery monitor keeps track of Wh the same way it does with Ah. You start at zero when fully charged, and then you subtract what you have used. If you use 120W for 1 hour you have are at -120Wh. The SOC is arbitrary number based on what you entered into the monitor. Say you told it you had a 1200Wh battery - your SOC would be (1200 - 120)/1200 = 0.9 = 90%. Just the same as Ah.
If you pull 90Ah out, your are at 10% SOC in terms of Ah, but you are actually at 8-9% SOC in terms of Wh.
A battery monitor keeps track of Wh the same way it does with Ah. You start at zero when fully charged, and then you subtract what you have used. If you use 120W for 1 hour you have are at -120Wh. The SOC is arbitrary number based on what you entered into the monitor. Say you told it you had a 1200Wh battery - your SOC would be (1200 - 120)/1200 = 0.9 = 90%. Just the same as Ah.
