How long to charge a charge is not fixed, and the charging time is determined according to the charging capacity and charging current. Charging capacity is, for example, a new battery with a capacity of 100Ah needs to charge 150Ah to be fully charged after discharging 100Ah, this 150Ah is the charging capacity, if it takes 15 hours to be fully charged according to the standard charging current of 10Ah, it is now the use of fast charging, that is, high current charging, the time can be reduced by half.