There are two kinds of multifunctional portable audio batteries, one is a rechargeable battery, and the other is a disposable battery. Disposable batteries are not rechargeable and have no charging circuit or interface. Rechargeable batteries, generally have charging interfaces. Specifically so charged: Find the portable audio charging interface (see the manual). Nowadays, most products are data cables and charging interfaces. Plug the USB port at the other end of the data cable into the USB port of the portable charging power supply, and then plug the portable charging power supply into the AC power outlet to charge. However, the charging voltage specified in the product manual is usually a 5V charger. If the voltage is too low, it will not be charged, and if it is too high, it will damage the battery, and even cause explosion or combustion. Therefore, the charging problem of portable audio, it is necessary to configure a suitable charger strictly according to the requirements of the product manual, so as not to damage the audio and battery. Another type of portable power interface is the concentric circle plug. Specifications range from 2 mm diameter to 5 mm diameter, depending on the interface diameter on your machine. The voltage value will be marked near the interface, such as 5V, find a suitable 5v charger, and plug it directly into the portable concentric circle power interface to charge while playing.