It is a portable product for supplying power for small-power loads. It has a built-in battery and a built-in solar controller. The solar controller samples parameters such as the battery's terminal voltage and capacity, the discharge current and the ambient temperature With help of a computer chip and computes through a special control module to realize efficient and accurate control over the discharge rate and the temperature compensation in line with characterisitics of the battery. With an efficient PWM charge mode, the battery can operate in the best status And have a long life.