Safety, lifetime, materials and manufacturability increasingly shape the battery race.
One number cannot describe a battery
Energy density matters for range and weight, but charging speed, cycle life, temperature tolerance and safety determine real usefulness.
The application sets the priority
A grid battery can accept more weight than an aircraft battery. Consumer electronics, vehicles and stationary storage therefore reward different chemistries.
Scale exposes new constraints
Promising laboratory materials must be produced consistently and affordably. Recycling pathways and secure supplies can become decisive as demand grows.