The invention discloses an internal short-circuit detection method of a
power battery. The internal short-circuit detection method comprises the following steps: detecting whether lowest
voltage of the battery is lower than the set value and lasts for the preset time or not when a vehicle runs again or is charged, if so, judging the existence of
short circuit, and performing maintenance operation on the battery through a prompt of a BMS (battery
management system); identifying the difference of the battery in the static state through the BMS when the battery is arranged at the
discharge tail end, if the difference in the capacity of the battery is too great, exceeds the set value and lasts for the preset time, judging the existence of the
short circuit in the battery, emitting an alarm through the BMS and reminding of performing the maintenance operation on the battery; and recording the number of times of achieving cutoff
voltage of the battery in the BMS, when the difference in the number of times of charge cutoff or
discharge cutoff of the battery is larger than the set value, judging the existence of the
short circuit in the battery, emitting the alarm through the BMS and reminding of performing the maintenance operation on the battery. According to the internal short-circuit detection method disclosed by the invention, the internal short circuit of the battery can be identified through a variety of means, and the internal short-circuit situation of the battery can be identified to the greatest extent by combining with a statistical method on the basis of long-term operation data.