With the gradual retirement of new-energy vehicle power batteries, real-time monitoring and data sharing for the life cycle of power batteries are an issue that needs urgent attention. However, data accessing and sharing between battery manufacturers, new-energy vehicle manufacturers and decommissioned battery users have not yet formed a multi-faceted mechanism. A blockchain-based power battery data sharing system is designed in order to solve this problem. Blockchain technology verifies that data is safe, traceable and non-deformable. At the same time, the feasibility of the scheme is tested by simulating the application scenario of the second-use battery in the energy storage system. The Raspberry Pi is used as the core to combine with the CAN driver chip sja1000 to develop the battery monitoring module. The system collects and publicizes the battery data on the chain, which ensures the user's privacy and the authenticity of the battery data in the database.