The text discusses the principles and development of sodium-ion batteries, which have similar operating principles to lithium-ion batteries and are already being used in electric cars with a range of around 300 km in China. It is predicted that by 2025, approximately 10 gigawatt hours of sodium-ion batteries will be installed worldwide. Researchers are focusing on developing new cathode materials with higher energy density and longer lifespan, and a project has been launched to use additive manufacturing technology for the production of sodium-ion solid-state batteries. The Swedish company Northvolt has made a breakthrough in the development of sodium-ion batteries, which have been known since the 1980s but have previously had lower energy density. NIBs are seen as a promising alternative or complementary technology to lithium-ion batteries, as sodium is abundantly available.