Contemporary Amperex Technology Co., Ltd. (CATL) unveiled its first-generation sodium-ion battery, together with its AB battery pack solution—which is able to integrate sodium-ion cells and lithium-ion cells into one pack.

The sodium-ion battery has a similar working principle to the lithium-ion battery; sodium ions shuttle between the cathode and anode. However, compared with lithium ions, sodium ions have a larger volume and higher requirements regarding structural stability and the kinetic properties of materials. This has become a bottleneck for the industrialization of sodium-ion batteries.

CATL has been dedicated to the research and development of sodium-ion battery electrode materials for many years. In terms of cathode materials, CATL has applied a Prussian white material with a higher specific capacity and redesigned the bulk structure of the material, which the company says solved the worldwide problem of rapid capacity fading upon material cycling.

For anode materials, CATL developed a hard carbon material that features a unique porous structure, which enables the abundant storage and fast movement of sodium ions, and also an outstanding cycle performance. The specific capacity of the material can reach more than 350 mAh/g. The overall performance is similar to that of graphite.

CATL developed a unique electrolyte system for the cathode and anode materials.

CATL’s first generation of sodium-ion batteries has the advantages of high-energy density, fast-charging capability, excellent thermal stability, great low-temperature performance and high-integration efficiency, among others.

The energy density of CATL’s sodium-ion battery cell can achieve up to 160 Wh/kg, and the battery can charge in 15 minutes to 80% SOC at room temperature. Moreover, in a low-temperature environment of -20 °C, the sodium-ion battery has a capacity retention rate of more than 90%, and its system integration efficiency can reach more than 80%. The sodium-ion batteries’ thermal stability exceeds the national safety requirements for traction batteries.

The first generation of sodium-ion batteries can be used in various transportation electrification scenarios, especially in regions with extremely low temperatures, where its advantages become obvious. Also, it can be flexibly adapted to the application needs of all scenarios in the energy storage field, CATL says.

CATL says that its next generation of sodium-ion batteries will exceed 200 Wh/kg.

AB system. CATL has also developed an AB battery system solution, which mixes and matches sodium-ion batteries and lithium-ion batteries in a certain proportion and integrates them into one battery system. The different battery systems are controlled through the BMS precision algorithm.

The AB battery system solution can compensate for the current energy-density shortage of the sodium-ion battery, and also expand its advantages of high power and performance in low temperatures. Thanks to this innovative structure system, application scenarios for the lithium-sodium battery system are expanded.

Dr. Qisen Huang, deputy dean of the CATL Research Institute, said that sodium-ion battery manufacturing is perfectly compatible with the lithium-ion battery production equipment and processes, and the production lines can be rapidly switched to achieve a high-production capacity.

As of now, CATL has started its industrial deployment of sodium-ion batteries, and plans to form a basic industrial chain by 2023. CATL invites upstream suppliers and downstream customers, as well as research institutions to jointly accelerate the promotion and development of sodium-ion batteries.