Why cannot charge 18650 Li-ion battery? What’s the solution?

18650 Li-ion battery is one of the popular Li-ion batteries used in electronical products. It is always used in laptop. However, during application, we can find that 18650 Li-ion battery sometimes cannot be charged. Now let’s find out the reasons.

High contact resistance leads to high voltage drop because of the dirt on electrode contacts. At this moment, the host regard that the battery is fully charged and stop the charging.

There is inner electrical failure, so that the battery cannot be charged normally.

There is anything wrong in 18650 Li-ion battery.

The solution of 18650 Li-ion battery charging failure

The interface of charger has electrical aging or has damaged inside, it’s necessary to change a new charger for testing.

The charging hole has been oxidized, which results in poor contact. It belongs to hardware failure. Connect the after-sales for further maintenance.

There is something wrong with the wire, just replace a new one.

The battery is overused or damaged, just change the battery.

18650 Li-ion battery maintenance principles

Principle one: there will be oxidization on metal surface of the battery after long-time usage, which causes poor contact between battery and mobile phone, and shorter cycle life. We can rub the Rusting by eraser or any other cleaning tools.

Principle two: low temperature may change the electrolyte inside, promote the chemical reaction. The using process of Li-ion battery is a process of charging and discharging. During this period, the anion and kation keep hitting each other, so that the battery will be gradually aging. If under normal indoor temperature, the power inside the electron will be larger, so the battery is in active state, and electric leakage will be more frequent. If put the battery into low temperature environment, the Li film on the surface of the battery, the microstructure of electrolyte, and their contact surface will change obviously, so that the battery inside stops being active and lessens electric leakage. Therefore, the stand-by time of the mobile phone will be longer.

The cycle life of Li-ion battery is over 600 times. If charge too much times, the thermal motion will gradually destroy the inner molecule microstructure and the charge storage efficiency will be lower. Freezing process can easily destroy the inner structure of the battery. It can strengthen the charging ability in a short time, but may be not valid after long time. It is impossible to recover completely when the microstructure inside the battery is destroyed. This method will accelerate damaging the battery if used frequently.

Principle three: deeply discharge the mobile phone by running out of electricity inside, so as to recharge more completely. Try to connect the mobile phone and a 1.5V small bulb. The electricity of the battery will transmit to the small bulb until all running out slowly. Normally, the mobile phone will shut down automatically if the nominal voltage is lower than 3.6V. After discharging, recharge the battery, and then the mobile phone can be used for a longer time.

18650 Li-ion battery maintenance methods

Take out the battery after running out of electricity, and carry out temperature controlling method. The cycle life of Li-ion battery will greatly shorten under unstable temperature circumstance, because part of the Li ion in the battery has contained memory electricity. Take the battery outdoor, and then indoor in winter. This method can discharge some of the memory electricity.

Take out the battery for a week and run out of the battery gradually. Make sure discharge completely by machine. Then recharge completely. It may be in a short time to charge fully. Switch off and recharge for several times.