As one of the four main materials of lithium batteries, the negative electrode material is very important to the improvement of the performance of lithium batteries, especially the breakthrough in capacity and battery life.
In this context, silicon-based anodes are generally recognized by the industry as an ideal next-generation anode material.
As one of the first lithium battery companies in China to apply silicon anodes, BAK has been deeply engaged in this field for many years. Recently, Dr. Lin Jian, the chief scientist of BAK, communicated the research progress of BAK on high-capacity silicon anodes.
According to data, my country’s silicon-based anode shipments will be 11,000 tons in 2021, a year-on-year increase of 83.3%. Although it only accounts for 1.5% of the anode material market share, it is in the early stage of development, but the prospects are considerable, attracting a large number of industry pioneers.
As Lin Jian said, “The increase in market demand for silicon-based anodes is mainly due to the rapid development of the new energy industry. In order to meet the high energy density requirements of future power batteries, it will promote the improvement of the cruising range of new energy vehicles, and the driving experience is comparable to that of fuel vehicles. Even surpassing gasoline vehicles and promoting full electrification.”
With industry-leading R&D progress and experience advantages, BAK is the first in China to use silicon as the negative electrode material for cylindrical batteries. In fact, compared with square and pouch cells, silicon-based anodes have natural advantages in the cylindrical field.
Compared with graphite, silicon will have a huge volume expansion of up to 300% during charging and discharging, while cylindrical batteries usually use steel shells, which have high mechanical strength and good binding force, which have high mechanical strength and good binding force, so that the expansion of silicon can be effectively suppressed. form a natural barrier.
At present, BAK’s silicon-oxygen materials have developed from one generation of silicon to three generations of silicon, increasing the first efficiency from 77% to 86%, basically matching the efficiency of the positive electrode, and adopting advanced lithium supplementation technology, the utilization rate of the positive electrode has gradually increased.
Behind the opportunities are often huge challenges. Compared with traditional materials, silicon-based anodes have obvious advantages in terms of specific capacity, cycle life, and safety, but at the same time, there are problems of high cost, high production technology threshold, and difficulty in large-scale production.
According to Lin Jian, BAK is currently conducting research on pre-lithium silicon-oxygen materials. Low first effect and fast capacity decay are the core reasons that restrict the commercial application of silicon-based negative electrodes. The pre-replenishment technology is used to improve the first effect of silicon-based materials, mainly by pre-supplementing part of lithium in silicon-based materials to reduce the process of charging and discharging. irreversible capacity loss.
With one generation of production, one generation of R&D, and one generation of reserve, BAK battery has always adhered to the product development model of advanced deployment for end products, which also makes BAK continue to lead the industry in battery performance.
Whether it is the pursuit of cordless portable, intelligent, and flexible small power field, or the field of new energy vehicles where the penetration rate of electrification continues to increase and mileage anxiety needs to be solved urgently, the industry-leading battery technology will lead the development of the industry and promote industrial transformation.
As Lin Jian said, BAK will continue to explore high-capacity silicon anode technology, challenge the performance limit of ternary lithium batteries, and strive to provide customers and consumers with higher-performance products and services.