At least that's how ZOOZ Power sees it and therefore has a new approach. Instead of batteries, they simply have flywheels. These can be accelerated to 17,000 revolutions per minute. Regaining the power is achieved by slowing them down again and using the motor as generator. The system is said to be significantly more cycle-resistant and significantly cheaper in the medium and long term.
I had the chance to let ZOOZ Power Germany show me such a storage system and explain it to me. It's an exciting topic and you can find my thoughts on it in this article.