Why are separators essential?

Separators are in charge of battery safety. Shown are 3 separators: Celgard (incumbent/competitor), Nanofiber (expensive separator), and Next-Ion.

The video demonstrates shrinkage of commercial separators as opposed to Next-Ion’s separator.

When you charge a battery it gets hot and the separator shrinks as shown. Once the separator shrinks then battery explodes. To prevent the battery from exploding and the separator from shrinking the battery can't be charged as fast.

However, if the you make a separator that doesn't shrink then you can build non-exploding batteries and batteries that can charge cars in 6 minutues.