CATL: Solid-state battery samples can be made, but commercialization is still a long way off

When accepting institutional research, CATL stated that the company has been deeply engaged in the research and development of solid-state batteries for many years and is currently in the first echelon. The company can already make solid-state battery samples, but it still has a long way to go before it can commercialize solid-state batteries.

At present, Chinese new energy vehicle manufacturers mainly use liquid batteries. However, in the next five years, relying on the existing ternary batteries, it is difficult to achieve the energy density target of more than 350Wh/kg, which cannot meet the national requirements. In addition, during the process of lithium iron phosphate switching to high nickel ternary batteries, many car companies have experienced battery spontaneous combustion accidents.

Solid-state batteries can solve energy density and safety issues. The biggest difference between solid-state batteries and current mainstream traditional lithium-ion batteries is the electrolyte. They use solid electrolytes instead of electrolytes and separators of traditional lithium-ion batteries. Liquid lithium batteries and solid-state batteries use solid electrolytes instead of liquid electrolytes, which greatly reduces the risk of thermal control.

Solid-state batteries have the following advantages:

Solid-state batteries replace liquid electrolytes with solid electrolytes, greatly reducing the risk of thermal runaway.

The electrochemical window of solid-state batteries can reach above 5V, which is higher than liquid lithium batteries (4.2V), allowing the matching of high-energy positive electrodes and metallic lithium negative electrodes, greatly improving the theoretical energy density.

Solid-state batteries can simplify packaging and cooling systems, further reduce battery weight in limited space, and increase volume energy density by more than 70% compared to liquid lithium batteries (graphite negative electrode), reaching 500Wh/kg.

However, solid-state batteries also have certain disadvantages. For example, their fast charging performance is not good, and the physical contact will deteriorate during the cycle, which will affect their service life. In addition, the preparation process of solid-state batteries is also very complicated.

CATL disclosed two patents on solid-state batteries in January this year, namely "a method for preparing a solid electrolyte" and "a sulfide solid electrolyte sheet and its preparation method". In addition, CATL also revealed at a recent shareholders' meeting that it will release sodium-ion batteries around July this year. Sodium-ion batteries may become a supplementary solution to lithium batteries due to their abundant raw material reserves and easy access to low costs.