the battery power is maintained at 40%-60%. The battery voltage will drop lower than the
over-discharge protection voltage level due to the self-discharge of battery if not charging the
battery for a long time, which will lead to fatal damage to the battery. Please be careful.
19. Prohibit charging the battery under the condition of fire or extreme heat. Do not use or
store the cleaner near the heat source.
20. Prohibit piercing the cleaner shell with nails or other sharp objects, and prohibit
hammering, impacting or throwing the cleaner