The 18650 means 18 mm in diameter and 65 mm in length. Generally, the 18650 battery is used in the industry. The common ones are used in laptop computer batteries and  flashlights.

18650 lithium-ion battery

The 18650 is just the size of the battery. It can be divided according to the type of battery. 18650 lithium ion battery, 18650 lithium iron phosphate battery, 18650 nickel hydrogen battery (rare), and the common 18650 is lithium-ion battery.

18650 lithium-ion battery repair method:

1. Run out of battery and use them after temperature treatment. The battery will greatly shorten the use time when the temperature is unstable, because the battery is not charged and a considerable part of the lithium ions have been used for memory. This method can make a part of the memory power release, winter is coming, put the batteries outside for a while, then take it to the house.

2. There is another way, to remove the battery, put it for about a week, the electricity will be slowly consumed, you need to use the machine to completely consume the batteries. Then fully charge, it is estimated that your current charging time must be very short, after the full, disconnected and then rucharge, repeated several times, absolutely effective.

The 18650 battery life theory is cyclic charging 1000 times. Due to the large capacity per unit density, most of them are used in laptop computer batteries. In addition, the stability of the 18650 is very good at work. It is widely used in various electronic fields: it is often used in glare flashlights. Power bank, wireless data transmitters, electric warm clothing, electric warm shoes, portable instrumentation, portable lighting equipment, portable printers, industrial equipment, medical equipment, etc.