Abstract: A low static current discharge protection circuit for mining battery packs with self-locking function has been designed to address the problems of high self loss, unreliable discharge protection, and serious self consumption after protection in the discharge protection circuit of mining equipment battery packs. The protection principles of three common discharge protection circuits for battery packs were introduced, as well as the function of low static current discharge protection circuits with self-locking function; detailed discussions were given on the design of each unit in the protection circuit, as well as two key technologies: protection window locking and static low-power processing. Verified by testing: the working current of the discharge protection circuit before protection is not greater than 2.5 mA; the static current after protection shall is not more than 15 μA, and the protection reliability rate is 100%; the safety performance and safe storage time of the mine storage battery are effectively guaranteed.