As mentioned before，the voltage can be used as a termination factor，i.e.，terminating the charging process when the battery voltage reaches a specific value.This method has some inaccuracies，because the real open-circuit voltage is obtained when the battery is left disconnected for some time after charging.This is because chemical reactions happening inside the battery need some time to stabilize.Nevertheless，this method is widely used.In addition，this technique is usually used with constant current techniques to avoid overheating damage to the battery.