New hydrogen cellphone battery can power an iPhone for a week (opens in new tab)

Two problems I can see: 1. You'd need a hydrogen source. 2. Exactly how much vapor does it release? Water vapor next to sensitive electronics, in your pocket, can be very bad.

This looks useful for military/industrial applications. It doesn't look practical for wide-spread consumer applications, any time soon.

Also I assume the recharge is pretty much instantaneous? Just re-fill it with hydrogen and you get another 7 days... That'd be pretty sweet

Heat production and water vapor are not typically desirable properties for smartphone batteries.