Because lithium batteries are lightweight, large capacity, long life, fast charging, but expensive.
Lithium batteries can be broadly divided into two categories: lithium metal batteries and lithium ion batteries. Lithium-ion batteries do not contain lithium in its metallic state and are rechargeable.
The fifth generation of rechargeable batteries, lithium metal batteries, was born in 1996, and is superior to lithium-ion batteries in terms of safety, specific capacity, self-discharge rate, and performance-to-price ratio.