1.Battery drain performance
Battery voltage does not go up and capacity decreases. Measure directly with a voltmeter, if the voltage at both ends of the 18650 battery is lower than 2.7V or no voltage. It means that the battery or battery pack is damaged. Normal voltage 3.0V ~ 4.2V (generally 3.0V battery voltage cutoff, 4.2V battery voltage will be fully saturated, individual also have 4.35V).
2.Battery Voltage
Battery voltage is lower than 2.7V, you can use the charger (4.2V) to charge the battery, after ten minutes, if the battery voltage has recovered, you can continue to charge until the charger prompts full, and then look at the full voltage.
If the full voltage is 4.2V, it means the battery is normal, and it should have been cut off by the last use which consumed too much power. If the full voltage is much lower than 4.2V, it means the battery is damaged. If the battery has been used for a long time, it can be determined that the battery life has come to an end and the capacity is basically exhausted. It should be replaced. There is basically no way to repair. After all, lithium-ion batteries have a life, not unlimited.
3.Voltage Display
If the measurement of 18650 lithium-ion battery pack, the battery has no voltage, this time there are two kinds of cases, one is the battery was good, long-term power loss caused by storage, this battery is a certain chance of recovery, generally with lithium-ion battery pulse activator (lithium-ion battery charger/discharger) to charge the battery many times over a short period of time, it may be possible to repair. The general cost of repair is not low, or buy a new one more cost-effective. Another possibility is that the battery is completely depleted, the battery diaphragm breakdown, positive and negative short circuit. There is no way to repair this kind of thing, you can only buy a new one.
4.Battery Voltage
To check battery capacity, set your multimeter to measure the amount of electricity passing through it per hour and place two metal rods on the positive and negative metal ends of the battery.
5.Check the multimeter display
Check the multimeter display. A fully charged 18650 lithium ion battery pack cell with milliamp hours mAh consistent with the labeling would indicate that the battery is in good condition for use. Measure the change in voltage during use, when the discharge voltage drops, if the reading is more than 5% below the labeled capacity, please charge your battery until it is full, and then test the battery again, if the realistic reading is still lower than the labeled capacity, please replace the battery in time because the battery can no longer supply power normally.
Post time: Nov-21-2023