Our company has optimal design to the power bank, so the power bank can protect circuit and when the power bank charged or discharged. It can control circuit. The power bank also can automatically identify the connected devices and automatically charge. This design can free maintain when power bank charge or discharge. Any normal operation will not damage the power bank with the lowest static current and highest conversion efficiency. Once you touch the button, the power bank will show the power. We will improve LED which can show the battery's software according to battery charge or discharges' curve. Power conversion circuit adopt high efficiency booster chip. The frequency is 1.2MHz. Output power conversion circuit adopts aboard materials which have high frequency and low resistance. Output switch control adopts large electricity (8A), low resistance, double MOSFET pipe to reduce loss. The output inductor adopts high power inductor in order to reduce the calorific value of the whole machine. These are meeting the standards of CE, FCE.