There are two possibilities: the battery inside the charging treasure aging, charging treasure due to frequent charging and discharging, coupled with battery quality problems, it is easy to make the battery aging, storage performance is greatly reduced. The voltage of the battery can be measured using the voltage gear of the multimeter. If the voltage drops too fast after connecting the charging device, the battery is also damaged. The booster board is short-circuited, the booster board components are damaged, and there is a short-circuit phenomenon, which makes the self-discharge of the charging bank serious. The solution to the problem: Replace the battery. Repair or replace the booster plate.