The traditional charging treasure has fixed capacity, the large-capacity body is heavy and inconvenient to carry, and the small capacity cannot meet the long-term endurance when going out. When charging multiple devices, it is necessary to carry multiple power supplies, which is complicated to store. The user's endurance demand is dynamic, short-distance travel does not require large volume, and long-distance travel requires higher power. This product adopts series modular design, solves the pain point of fixed power, realizes the free combination of power, and takes into account the portability and endurance.