Sodium ion battery negative electrode sei film forming agent and pre-sodiumization method, sodium ion battery

Abstract

The invention discloses a sodium ion battery negative electrode SEI film forming agent and a pre-sodiumization method, and a sodium ion battery, the sodium ion battery negative electrode SEI film forming agent includes a first film-forming solution and a second film-forming solution, The first film-forming solution is an aryl sodium solution, and the second film-forming solution is an organic solvent with or without adding a negative electrode film-forming additive. The SEI film forming agent for the negative electrode of the sodium ion battery can form a stable SEI film on the surface of the negative electrode material of the sodium ion before the battery cycle, thereby improving the cycle stability, the first coulombic efficiency and the energy density of the sodium ion battery.

Description

technical field [0001] The invention belongs to the technical field of sodium ion batteries, and in particular relates to a sodium ion battery negative electrode solid-electrolyte interface film (SEI film) forming agent, and also relates to a sodium ion battery negative electrode SEI film forming agent used to pre-sodium ion battery negative electrode The pre-sodiumization method further relates to a sodium-ion battery. Background technique [0002] With the development of new energy sources, more and more clean energy sources are widely used instead of fossil fuels, such as wind energy, solar energy, hydro energy, tidal energy, etc. However, the conversion of these energies into electrical energy is affected by the weather. For example, solar energy can only generate electricity during the daytime, and the power generation is unstable due to strong light and weak light. Direct access to the Internet will cause damage to the power grid, and wind power cannot generate electri...

AI Technical Summary

Problems solved by technology

However, these methods are difficult to apply in the actual full battery

For example: the content of the electrolyte in the full battery is limited; the proportion of fluoroethylene carbonate (FEC), a commonly used negative electrode film-forming additive, in the electrolyte is usually lower than 2%, otherwise the positive electrode will be damaged; the ether electrolyte is above 4V It will decompose and cannot be applied; the cost of ionic liquid is high and it is difficult to use it practically

Therefore, the SEI film on the surface of the negative electrode is difficult to be fully improved in the full battery, which greatly reduces the performance of the battery.

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