Why can't the 18650 battery be charged after it is dead?

First, the emergence of power depletion and non-charging in China is actually a case of battery-managed overdischarge.

The 18650 battery is a lithium ion battery. Battery recycling line Ordinary battery is 18650, rated voltage is 3.7V, and it has a storage range of about 2.5V to 4.2V. That is to say, the battery will be 4.2V when it is fully charged, and there will be no power supply of about 2.5V when it is discharged.

In the overall design of lithium-ion Battery Chargers, in order to play a safety role, when the battery into the charging tank, there will be a difference at the beginning of the charging process, that is, whether the battery charging through the voltage difference is a lithium-ion battery. lithium battery welding machine As a general rule, if the battery voltage is less than 2.0 V, it is not considered a lithium-ion battery, so the Charger does not charge the battery, which can simply avoid user misoperation (such as a dry battery or nickel-metal-hydride-cadmium battery) , lead to safety accident.

All the above functions are simple and practical. mounting machine Early or simple chargers will add this function. The disadvantage is that the voltage is 0 volts, or the lithium-ion battery that has not been used for a long time discharges below 2.0 volts in the air, and the charger cannot charge the battery through the protection panel.

Of course, the 18650 situation of power depletion and failure to charge (overdischarge) could actually be resolved. Activating the protected battery is not difficult for a practical technician. It can also be solved manually by finding a battery with voltage, positive to positive, negative to negative. However, this method only applies to protected batteries. If used in overdischarge batteries, may be due to excessive shock current and direct damage to the battery.