Type: 9V Li-ion Rechargeable batteryMaterial: lithium batteryVoltage: 8.4v (VERY Important to know this,it means normal working voltage and Fully charged voltage all are about 8.4v ,please make sure that your devices can work at 8.4v before bid. )Built-in battery capacity:500mAhBuilt-in battery energy: 3.7WHSize: 48x26x16mmProduct weight: about 26gSelf-discharge current: 20uAImportant note:Please don't give us bad comments. Please contact our customer service immediately before giving us bad comments. We will try our best to help you solve this problem!If you are satisfied, please give us five-star praise and encouragement, thank you very much!