Bandai Namco announced the release one of the best mobile phone / tablet charger for the retro gamers and Famicom Pac-Mam style charger. As you can see the device totally looks like a famicom cartridge but it’s a powerbank inside.
You can buy it from the official Bandai store from Japan for 4500 Yen (with tax) from 2017 May from here: http://d2w5pgwrin5wfg.cloudfront.net/extras/pacman1.html