They sell double-AA sized rechargeable batteries for XBox controllers. https://www.xbox.com/en-GB/accessories/batteries-chargers/play-and-charge-kit https://www

They sell double-AA sized rechargeable batteries for XBox controllers. https://www.xbox.com/en-GB/accessories/batteries-chargers/play-and-charge-kit https://www.xbox.com/en-GB/accessories/batteries-chargers/pl... This specific battery is unlikely to work for other devices because the controller has an extra connector, presumably to detect it and control charging (which happens over a USB cable). You'd at least need an XBox controller to charge it.