Phones with 8,000mAh to 10,000mAh batteries used to be a trade-show curiosity. Not anymore. The vivo T5 Pro shipped with a 9,020mAh cell, and the Redmi Note 17 Pro Max has already been confirmed at 10,000mAh, Gadgets Now reports. Batteries that size used to demand a phone thick enough to double as a doorstop, but the same chemistry now lets manufacturers fit 7,000mAh or more into bodies under 8.5mm, per Gadgets Now.