Does the SunJack come with a battery? Yes! Each SunJack comes with battery pack that gives you power to charge your devices even when the sun isn’t shining. If you have your own portable battery, you can also use with the SunJack, but our battery is optimized for maximum charging speed from the SunJack. Can I charge the SunJack battery from a wall outlet? Yes! The battery can also charge from any standard micro-USB plug. This is useful if you’re going on a trip and want to have maximum charge with no down-time.