In recent years, lithium-ion battery fire accidents (such as Note7, Tesla, etc.) are summarized as internal short circuits, lithium evolution, high temperature, and volume changes.

　　Choosing lithium iron phosphate batteries is not foolproof. Therefore, in the design and application of lithium batteries, the safety of lithium batteries should be guaranteed from multiple levels such as battery cells + PACK + BMS + system + cloud computing / big data, so as to avoid thermal runaway fire accidents of lithium batteries as much as possible.

　　Selection of battery cell material system: Priority is given to lithium iron phosphate with high safety performance, which has high thermal runaway temperature, slow heat production rate, and less total heat production, which fundamentally guarantees safety

　　Safety design of cell structure: The mechanical structure of PTC can cut off the short circuit of the cell in time to inhibit temperature rise; the mechanical structure does not work in the case of a short circuit inside the cell, and the functional coating inhibits the shrinkage of the isolation film to avoid large-area internal short-circuit;

　　Battery module PACK safety design: laser welding avoids the risk of screw loosening; multiple temperature sensors ensure real-time monitoring of the internal temperature and voltage of the module; insulation protection plate protects the positive and negative terminals, and the surface of the battery cell is covered with insulating film to ensure the battery core and external circuit Insulation performance.

　　BMS safety design: three-level BMS architecture, conventional V, I, T sampling detection, equalization, threshold alarm protection + internal short circuit algorithm + internal temperature estimation algorithm + lithium analysis estimation algorithm to ensure that the battery does not have thermal runaway.

　　System safety design: Intelligent battery control system can control a single group of voltage, current, and power to avoid bias and circulation; the cabinet-level fire protection system can quickly suppress thermal runaway.

　　AI security assurance: critical data is uploaded to the cloud, battery status is monitored in real time, and monthly/day-level security warnings are carried out in advance through horizontal and vertical comparison + database + security algorithm analysis.