.Meet the relevant national standards and requirements for batteries .All finished battery products are calibrated and tested before delivery. They can be used directly and normally.This 18650 3.7V 5800mAh lithium battery is composed of two 18650 2900mAh single cells. The technical point of this battery is that it has many wires. In fact, each wire has its function. The applied electrical appliances and the use environment determine these special parameters. If the battery you need is used in a cold place, you may need a low-temperature lithium battery. If your battery is used in a high-temperature environment, then you need a high-temperature lithium battery. If your product requires Used in communication products, the battery requirements will be very high, and we will also determine according to your specific requirements. If we continue to confirm with you the electrical appliances used and more detailed parameter requirements during the communication process, please do not be impatient, because we need to ensure that the battery configured for you is suitable for your product; we are upholding responsibility My heart comes to communicate with you. 