Analysis of safety solutions for lithium battery packs

1. Improve the safety of the electrolyte. By adding functional additives, using a new type of lithium salt and using a new type of solvent, the potential safety hazards of the electrolyte of the lithium battery pack can be effectively solved. According to the different functions of additives, the important ones can be divided into the following categories: safety protection additives, film-forming additives, positive electrode protection additives, stabilizing lithium salt additives, lithium precipitation promoting additives, current collector anticorrosive additives, and wettability enhancing additives. Regarding solvents, many researchers have proposed a series of new organic solvents, such as carboxylic acid esters and organic ethers. In addition, ionic liquids also have a class of high-safety electrolytes, but relatively commonly used carbonate-based electrolytes. The viscosity of ionic liquids is orders of magnitude higher, and the conductivity and ion self-diffusion coefficient are low. There is still a lot of work before practicality. To do. 2. Improve the safety of electrode materials. Lithium iron phosphate battery packs and ternary composite materials are considered to be low-cost and high-safety cathode materials, which may be popularized in the electric vehicle industry. Regarding the positive electrode material, the common method to improve its safety is coating modification. For example, the surface coating of the positive electrode material with a metal oxide can prevent the direct contact between the positive electrode material and the electrolyte, inhibit the phase change of the positive electrode material, and improve Its structural stability reduces the disorder of cations in the crystal lattice to reduce heat generation by side reactions. Regarding the negative electrode material, because the surface of the lithium battery is often the most prone to thermochemical decomposition and heat generation, improving the thermal stability of the SEI film is a key method to improve the safety of the negative electrode material. Through weak oxidation, metal and metal oxide deposition, polymer or carbon coating, the thermal stability of the negative electrode material can be improved. 3. Improve battery safety protection design. In addition to improving the safety of battery materials, such as setting battery safety valves, thermal fuses, connecting components with positive temperature coefficients in series, using thermally sealed diaphragms, loading dedicated protection circuits, dedicated battery management systems, etc., It is also a means to enhance security. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: What is the difference between iron-lithium batteries and lead-acid batteries?