Recently, at its online "Tech Zone" technology launch event, global power battery giant CATL officially unveiled its first-generation sodium-ion battery and simultaneously released the innovative AB battery system. The system integrates sodium-ion batteries and lithium-ion batteries into the same battery pack, aiming to further enhance overall performance through the complementary characteristics of the two cell types.
As a leading global battery supplier, CATL currently supplies lithium-ion batteries to multiple automakers including Tesla and Hyundai. According to data from South Korea's SNE Research, since 2021, CATL has held nearly 30% of the global EV battery market, ranking first. Facing the challenges of lithium-ion batteries in terms of resource sustainability, CATL has continuously invested in the R&D of sodium-ion battery electrode materials for many years. However, sodium ions are relatively large in size, which places higher demands on the structural stability and kinetic performance of the materials.
The first-generation sodium-ion cell released this time achieves an energy density of 160Wh/kg. Although lower than mainstream lithium-ion batteries, it supports charging to 80% state of charge (SOC) in just 15 minutes at room temperature, and maintains a capacity retention rate of over 90% in sub-zero low-temperature environments, demonstrating excellent fast-charging and low-temperature performance. These characteristics are particularly practical for EV users in high-altitude or severely cold regions.
Since sodium-ion batteries work on a similar principle to lithium-ion batteries—both operating by shuttling ions between the positive and negative electrodes—CATL has creatively introduced the AB battery solution. This solution mixes sodium-ion batteries and lithium-ion batteries together in a single battery pack, using the high energy density of lithium-ion batteries to compensate for the shortcomings of sodium-ion batteries, while relying on the high power output and stability of sodium-ion batteries at low temperatures to enhance the battery pack's adaptability to harsh environments.
According to CATL, the company has already initiated the industrialization layout of sodium-ion batteries and plans to establish a basically complete industrial chain by 2023. Meanwhile, the company has set the energy density target for the next-generation sodium-ion battery at over 200Wh/kg.
Currently, sodium-ion batteries still lag behind top-tier lithium-ion batteries in energy density (for example, Tesla's 4680 battery is believed to exceed 300Wh/kg), but they have clear advantages in fast charging and low-temperature performance. Before pure sodium-ion battery technology matures, the AB battery pack may serve as an effective transitional solution that balances performance and cost.