Sodium batteries are coming! Replace lithium battery?

  The chairman of CATL, Zeng Yuqun, stated at the shareholders meeting that the sodium-ion battery technology of CATL has matured and will be released around July 2021.

  According to reports, the average energy density of sodium batteries is 90-150Wh/Kg, which is lower than the 250Wh/Kg of lithium batteries. Calculated according to the energy density of a lithium battery of 250Wh/Kg, the weight of a lithium battery is 400 kg, and the weight of a sodium battery is calculated at 150Wh/Kg, and the weight will increase to about 650 kg. The analysis believes that the commercialization is unlikely to be required for the light-weight passenger car.   

  Therefore, the alternative scenarios for sodium-based batteries are in the areas of partial energy storage and small power batteries for two-wheelers. Compare the energy density of lithium ion and sodium ion batteries: Due to the low energy density, sodium batteries are suitable for scenarios similar to the current use of lithium iron phosphate batteries. These include short-range electric vehicles, energy storage systems (ESS), power companies' backup power supplies, etc.   

   In addition, many institutional research reports also pointed out that sodium ion batteries cannot be embedded in graphite materials due to the ion radius larger than lithium ions, and can only use hard carbon or other negative electrode materials with lower energy density. Also due to the large radius of sodium ions, it affects the charge and discharge rate of sodium ion batteries, and also leads to poor battery reversibility, low energy density utilization, and rapid energy density decline after multiple charges and discharges.  

   It is reported that sodium-ion battery is not a new technology. Related research started earlier and has been applied in practice. There is no so-called "breakthrough" innovation, but more iterative technology.