Method for quickly estimating capacity of battery pack based on residual charging capacity of single battery pack

The invention relates to a method for quickly estimating the capacity of a battery pack based on the residual charging electric quantity of a battery, and aims to solve the problem that the capacity of a formed and sorted battery is known, the SOC is slightly different due to a self-discharge factor, and then the capacity is estimated. The method comprises the following steps of: selecting a charging reference curve, calculating the SOC of a single battery, calculating the capacity of a battery pack, taking a minimum residual discharge electric quantity curve as a discharge reference curve, and calculating the difference between the maximum residual discharge electric quantity and the minimum residual discharge electric quantity in the battery pack to obtain the residual discharge time range, thereby obtaining a voltage value on the discharge reference curve by utilizing an interpolation method; and correcting a voltage difference caused by the internal resistance difference, finally predicting a voltage rang