A method for smoothing a charge power limit of a battery, comprising: measuring a terminal voltage and a current of the battery; determining an instantaneous power of the battery based on the measured terminal voltage and the measured current; and determining (S840, S850) a charge current limit and a charge voltage limit of the battery, characterized in that the method further comprising: determining the charge power limit of the battery equal to the charge current limit multiplied by the charge voltage limit, the charge power limit being a power that the battery can be supplied for a predefined time with the charge current limit and the charge voltage limit; determining a first weighting factor based on a given maximum charge voltage and the measured terminal voltage; determining a second weighting factor based on a previous smoothed charge power limit, the charge power limit and the instantaneous power; setting a smaller one of the first weighting factor and the second weighting factor as a first reference weighting factor; smoothing the charge power limit based on the previous smoothed charge power limit and the first reference weighting factor using a following equation: P s _ c = W LPF _ c P s _ c _ pre + 1 − W LPF _ c P raw _ c wherein W LPF_c is the first reference weighting factor, P s_c_pre is the previous smoothed charge power limit, P raw_c is the charge power limit, and P s_c is the smoothed charge power limit; and transmitting a notification signal indicating the smoothed charge power limit to an external device. measuring a terminal voltage and a current of the battery; determining an instantaneous power of the battery based on the measured terminal voltage and the measured current; and determining (S840, S850) a charge current limit and a charge voltage limit of the battery, characterized in that the method further comprising: determining the charge power limit of the battery equal to the charge current limit multiplied by the charge voltage limit, the charge power limit being a power that the battery can be supplied for a predefined time with the charge current limit and the charge voltage limit; determining a first weighting factor based on a given maximum charge voltage and the measured terminal voltage; determining a second weighting factor based on a previous smoothed charge power limit, the charge power limit and the instantaneous power; setting a smaller one of the first weighting factor and the second weighting factor as a first reference weighting factor; smoothing the charge power limit based on the previous smoothed charge power limit and the first reference weighting factor using a following equation: P s _ c = W LPF _ c P s _ c _ pre + 1 − W LPF _ c P raw _ c wherein W LPF_c is the first reference weighting factor, P s_c_pre is the previous smoothed charge power limit, P raw_c is the charge power limit, and P s_c is the smoothed charge power limit; and transmitting a notification signal indicating the smoothed charge power limit to an external device. determining the charge power limit of the battery equal to the charge current limit multiplied by the charge voltage limit, the charge power limit being a power that the battery can be supplied for a predefined time with the charge current limit and the charge voltage limit; determining a first weighting factor based on a given maximum charge voltage and the measured terminal voltage; determining a second weighting factor based on a previous smoothed charge power limit, the charge power limit and the instantaneous power; setting a smaller one of the first weighting factor and the second weighting factor as a first reference weighting factor; smoothing the charge power limit based on the previous smoothed charge power limit and the first reference weighting factor using a following equation: P s _ c = W LPF _ c P s _ c _ pre + 1 − W LPF _ c P raw _ c wherein W LPF_c is the first reference weighting factor, P s_c_pre is the previous smoothed charge power limit, P raw_c is the charge power limit, and P s_c is the smoothed charge power limit; and transmitting a notification signal indicating the smoothed charge power limit to an external device. wherein W LPF_c is the first reference weighting factor, P s_c_pre is the previous smoothed charge power limit, P raw_c is the charge power limit, and P s_c is the smoothed charge power limit; and transmitting a notification signal indicating the smoothed charge power limit to an external device.