LiFePO4 batteries are highly safe, have no risk of explosion and fire, and are environmentally friendly, non-toxic and non-polluting. No memory effect - the battery can be charged in any state of discharge, giving you peace of mind. Nominal Voltage:72V Nominal capacity:20.8Ah Working voltage:2.0V~3.65V AC impedance resistance(1khz):≤0.4mΩ Max. pulse charge / discharge current: 40A Dimension: 320mm(L)*206(W)mm*70(H)mm Weight: 8.34kg