Why doesn’t the percentage show 100% when the voltage meter is higher than 12.8 V which is said to indicate a fully charged battery?

Why doesn’t the percentage show 100% when the voltage meter is higher than 12.8 V which is said to indicate a fully charged battery?

Why doesn’t the percentage show 100% when the voltage meter is higher than 12.8 V which is said to indicate a fully charged battery?

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