... , can run for 4h after being rechargedBattery Rechargeable lithium polymer battery, 7.4V, 1600mhShell material ABS plasticClassification II Class-BFAlarm functions Rate, Volume ... No., AIR, OCCL.oOVER.EMPTYWeight OVER, OCCL., Air, Empty, Low battery, Control abnormal, No AC power supply, Installation error, Serious low ...