Self-generated negative electrode sodium replenishment technology accelerates the "breakthrough" of sodium batteries!

According to market information, recently, Changgao New Materials and Zhiyuan Sodium Technology signed a cooperation agreement on the self-generated negative electrode sodium replenishment technology. The two parties will jointly conduct research and development based on depositing ultra-thin sodium strips on the coated aluminum foil substrate, aiming to achieve technological breakthroughs in capacity and cycle stability of self-generated negative electrode sodium batteries, and provide a "material - cell" collaborative solution for the industrialization of sodium batteries.

In terms of technology, sodium replenishment is one of the pain points in the industrialization of sodium-ion batteries. This is because during the first charge-discharge cycle of sodium batteries, the decomposition of the electrolyte to form the SEI film consumes a large amount of active sodium ions, causing irreversible loss of sodium ions, which will directly lower the initial Coulomb efficiency and compress the actual available capacity of the battery. At the same time, in the self-generated negative electrode system, the uniformity and stability of sodium deposition may also affect the cycle and safety performance of sodium batteries.

According to the data, this cooperation adopts the ultra-thin sodium strip pre-replenishment technology route. Relying on Changgao New Materials' coated aluminum foil as the base, the ultra-thin sodium strips are precisely deposited on the collector surface. This not only can provide an early replenishment of active sodium sources, but also can improve the uniformity of sodium deposition, thereby raising the initial efficiency and increasing the available capacity of the cell, and at the same time alleviating the problems of dead sodium and sodium dendrites that may cause cycle degradation.

From an industrial perspective, the cost of hard carbon negative electrodes is relatively high. Zhiyuan Sodium Technology is a pioneer in the industrialization of sodium-free battery. Battery China Network learned from the recent industrial chain research that the company has deeply explored the sodium-free technology route and has omitted traditional negative electrode materials. This route has the potential to reduce costs and improve the energy density of the battery, but it is still limited by the problems of sodium source supply and deposition control for a long time. This cooperation between the two parties is expected to further accelerate the verification process of this technical route.

Currently, there are multiple sodium replenishment technology routes in China, including electrolyte additives, chemical pre-replenishment, and metal sodium strips. Most of them are still in the pilot verification stage. The processing of metal sodium, mass production technology, and safety control are still the key and difficult points in this field. With the deepening of the cooperation between the two parties, it is expected to further promote the iteration of related processes and provide a feasible path for the breakthrough of the first efficiency pain points and negative electrode bottlenecks in the sodium battery industry.