Battery comprehensive tester is used for all lithium-ion battery packs with CH+P+CH - P - ports to test various comprehensive performance parameters of the battery pack. The main test items include open circuit voltage, AC internal resistance continuous charging current, continuous charging voltage, continuous discharging current, continuous discharging voltage, charging overcurrent protection current, discharging overcurrent protection current, short-circuit protection time, overcurrent delay time, and post-test voltage etc.