Battery doesn't work
2pcs 3.7V lithium batteries are series connected together to provide 7.4V voltage for pump. Since the circuit is simple, there is no over discharging protection. There is a simple way to reactive the battery by using the mobile phone charger(5Vdc) to charge each battery(3.7Vdc) for 1-3 min, the battery will be ok. But is cst charged in wrong direction will cause the problem, so it’s better to return to our warehouse to recharge.
