Features: The AA & AAA nickel-zinc rechargeable batteries adopt environmentally friendly material of nickel positive and zinc negative without heavy metal. The working voltage range is 1.85V-1.3V, which is compatible with alkaline batteries and has a wider range of use. Especially for smart electrical equipment, the advantages are more obvious and the effect is outstanding. The battery itself can be discharged to 0.2V. For high-current, high-voltage and high-power electrical appliances, it is significantly better than the disposable alkaline batteries. The environment temperature for electrical appliances is -30 to 80 degrees. It can be discharged at a rate of 1-3C for continuous discharge and 10C for instant discharge. It is so far the safest battery in the world.