What should I do if the flashlight factory battery cannot be charged

Most flashlights are 4~6V small lead electricity, and small flashlights like this one are 4V small lead electricity.What should I do if the flashlight factory battery cannot be charged?

1. The flashlight factory battery cannot be charged. First, check the whole charging circuit line by line to confirm whether the resistance and capacitance are burst, whether the four rectifier diodes are normal, whether the two wire ends on the small battery are corroded and separated, and finally plug in the battery to confirm that the indicator light is normal and the output power is normal, which can prove that the battery cannot be charged.

2. There are two reasons why the flashlight factory battery cannot be charged:

a) The lead battery is small in size, and the electrolyte is small, and the resistance and capacitance charging is also easy to overcharge. Because the circuit is too simple and there are no protective measures, when the 4V battery is fully charged and not unplugged, there will always be 4.5V upward voltage added to it, so the battery is easy to overcharge. The harm it brings is that water vapor can emerge from under the plug, and over time, there will be water shortage, and the dry plate cannot be powered.

3. Because of the lack of electricity, it will be charged, the flashlight factory battery will be hot and bulging, and the electric pile will corrode the copper wire if it leaks.

4. Some flashlights are out of power and you don't recharge them, resulting in a loss of power. In addition, the overcharged internal positive plate decays and becomes powdery, which makes the water turbid and leaks electricity. When the flashlight factory is fully charged and discharged, it runs out the next day.

5. Is the flashlight factory, a small lead electricity, being decided whether to scrap? To see if it has leakage, if it cannot be charged, open the cork and add 2 ml of distilled water, and then close the cork and fix it until it is fully charged.

6. This low-quality flashlight factory should not be bought. 18650 lithium battery is more durable. My flashlight only uses the old flashlight shell. Put the old battery of the mobile phone in parallel. The shell is large enough to put the mobile phone charging board. As long as you string a diode on the 5V1A, it will not go wrong in a few years, and it will be as good as new after being fully charged and discharged for a year.