The battery onboard lasts approximately 12 hrs. Not the best in the list, but ideal for a complete day of listening �?check out the Tribit XSound Plus 2 If you would like some thing with longer battery life to the same form of cost (though it's bulkier). Audio efficiency: https://www.bluetoothspeaker.top/bluetooth-speaker-wireless-speaker-stereo-sound-bluetooth-5-0-with-rgb-lights/