question

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Voltage / stage of charge percentage of a Victron Super Cycle AGM battery

I want to know what voltage relates to what state of charge for a Victron Super Cycle AGM battery, as I think it differs from a standard AGM battery. If anyone knows the voltage for state of charge in 10% increments from 0% to 100% it would be greatly appreciated, thanks!

CCGX Color ControlvoltageAGM Batterybattery system voltage
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wkirby answered ·

In any battery, Voltage does not track State of Charge very well at all. Many factors influence the battery Voltage including temperature, the current flowing into or out of the battery, its age and the number of cycles including the depth of those cycles.
The Voltage can change significantly between changing from a 10A discharge and 10A charge in one second without the SOC moving at all.
Additionally, the Voltage would not track linearly down in step with SOC.

SOC can only be properly represented by counting the energy into and out of the battery and applying Peukerts exponent to the calculation and accounting for charge inefficiencies. This is the job of the BMV or SmartShunt components.

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I know that voltage doesn't accurately track state of charge and it's not a linear scale, but I want to know the related values so that I can measure the voltage of a new AGM Super Cycle battery and check if it's at 100% or what percentage it is at, to accurately calibrate the BMV.