If we go the way we need to, most battery applications (by total battery storage, not by unit produced) won't need space or weight constraints. Of course a car

If we go the way we need to, most battery applications (by total battery storage, not by unit produced) won't need space or weight constraints. Of course a car or phone phone will need to be lithium but there's no reason a Tesla powerwall (currently lithium) couldn't be 0.5x bigger; or certainly grid level electricity storage (currently CA has one second? I think and there is a plan to expand to three days of grid level). Probably even some semis or buses would be ok with a bigger battery