2x 18500 1000mAh 3.2V Batteries LiFePO4 Rechargeable Battery for Solar Light
You're replacing 3.2V LiFePO4 18500 Lithium Batteries, not 18500 3.7v Li-ion Batteries! 18500 3.2V Batteries. 18500 3.2V Batteries for Garden Solar Lighting: Roma, George, Solar LED Garden Light, Lights with or without sensor.