You may be cheaper buying a new one, or use it with a power bank and usb cable. It is a Li-ion Battery / DC5V. If your technically minded and have small precision screwdriver set you could take it carefully apart, find the battery and replace (you would probablly need soldering skills as well) it with the same capacity Li-ion Battery / DC5V. Honestly buy a new one or use a power bank and USB cable.
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You may be cheaper buying a new one, or use it with a power bank and usb cable. It is a Li-ion Battery / DC5V. If your technically minded and have small precision screwdriver set you could take it carefully apart, find the battery and replace (you would probablly need soldering skills as well) it with the same capacity Li-ion Battery / DC5V. Honestly buy a new one or use a power bank and USB cable.