Abstract: A method for updating voltage difference of battery includes presetting a relationship of voltage difference of the battery vs. state of charge of the battery, detecting a state of charge-1 of the battery, and determining a first voltage difference of the battery according to the state of charge-1 of the battery. The method further includes updating the relationship of voltage difference of the battery vs. state of charge according to the first voltage difference of the battery. A method for estimating state of charge, an electronic device, and a non-transitory storage medium are further provided.