The possibility that the lithium battery can not be charged simply has the following two situations (exclude the power problem, determine the power supply is certainly good oh).
First, the lithium battery protection board problem.
At present, most of the lithium battery products used in the market are battery packs containing protection boards, the general functions of the protection board are: 1, anti-overcharging (overvoltage protection);
2, overdischarge protection (the general voltage is lower than 2.8-2.4V, the protection board will stop output);
3, overcurrent protection (normal protection board generally set the discharge current for the battery capacity of about 1C-3C, special requirements will be 5C discharge (C here refers to the battery capacity).
Your lithium battery can not be charged, it is likely that the battery cell is overdischarged (not used for a long time, placed lithium battery batteries will be prone to this problem, the battery cell is placed for a long time, due to the power consumption of the battery voltage is placed below 2.4, and the protection board, no 0V charging function,) then because the protection board can not detect the battery exists (the battery voltage is below the threshold), So it can't be charged. The solution is simply to use a voltage limit of 3.7V below the power supply directly to charge the cell, the battery voltage to the protection board detection threshold above, the method must be: pay attention to limit the charging voltage & The current prevents the battery from overheating and blowing up.
< br >
Second, the battery is damaged, placed for a long time, the battery has been completely overdischarged electrolyte (liquid) dry, can only replace the battery. (The probability of cell damage is proportional to the time of long time, if the battery capacity is less than 1000mA, and it is placed for more than 2 years, the possibility of cell drying leading to capacity reduction, or even no charging is very large.
If you do not charge, there are several situations:
< br >
1. The lithium battery is in an over-discharge state
< br >
That is to say, the lithium battery discharge is very low, in a deep discharge state, the power is basically used up, so that as low as the lithium battery cut-off voltage, at this time you can take the activation method, but this is not necessarily effective;
< br >
2. There is a problem with the charger or charging line
< br >
First of all, we should check whether there is a problem with the charger, the method is very simple, direct output voltage or load observation of the corresponding voltage, as for the line there is a problem, then it has to spend some effort, after all, it involves circuit hardware and other problems, when necessary, direct disassembly analysis;
< br >
3, lithium battery used for a long time, battery failure
< br >
The possibility of this happening is relatively small, but it cannot necessarily be ruled out that your own battery should be familiar with how long it takes to change the battery;
< br >
4, battery charging IC or BMS system problems
< br >
Due to the imbalance of the battery cells and other reasons, the battery management system has problems, which leads to the management IC misjudgment and can not detect voltage or current.
It should be noted in the use of lithium batteries that the battery enters a dormant state after being placed for a period of time. Self-discharge will cause the battery to run out of power, and the capacity is lower than normal, resulting in too low battery power and no charge. But lithium batteries are easy to activate, as long as 3-5 normal charging and discharging cycles can activate the battery hope to help you oh.