Forum Discussion
jrnymn7
Oct 28, 2014Explorer
As for surface charge vs. 'real' charge... there will always be a level of surface charge, regardless of the charging voltage or charge rate. To prove this, all one needs to do is start charging a battery at any voltage setting of their choosing... charge for say 15 minutes, or to what you believe to be 90% charged... turn off the charger... and watch the voltage reading quickly drop.
This is why voltage readings cannot be used to determine battery SOC, while under load or being charged. Only by counting Ah's replaced can one accurately determine SOC while charging. Likewise, static amps at near full charge can also give a good indication of SOC.
This is why voltage readings cannot be used to determine battery SOC, while under load or being charged. Only by counting Ah's replaced can one accurately determine SOC while charging. Likewise, static amps at near full charge can also give a good indication of SOC.
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