Method for determining state of charge of battery, battery management system and electric device

The invention relates to a method for determining the state of charge of a battery. The method comprises the following steps: a) acquiring the state of charge at the current sampling moment tn; b) the voltage Vn, the temperature Tn and the charging rate Cn at the sampling time tn and the voltage Vi at the sampling time ti are obtained, the voltage difference Vn-Vi is calculated, and the sampling time ti is the time when the state of charge of the battery is obtained within a preset time period before the sampling time tn; c) when the voltage difference Vn-Vi is greater than or equal to a preset voltage threshold value, calculating a voltage change rate according to the voltage difference Vn-Vi and the time difference tn-ti; and d) when the voltage change rate is greater than or equal to a preset voltage change rate threshold value for the first time, according to the temperature Tn and the charging rate Cn of the battery at the sampling time tn, obtaining the corrected state of charge of the battery as the ac