Solid-state Battery

It promises higher energy density and safety. It is still in development for cars. Production cost is a challenge. Researchers and manufacturers are working on different solid electrolytes, such as sulphides, oxides and polymers. Advantages could include faster charging and a lower fire risk, but durability, manufacturing and cost still need to be proven at scale. Some semi-solid designs are a step between liquid and fully solid electrolytes.

Ions move through a solid material between the electrodes.

Claims about timelines vary. Not yet common in production cars.