Household LED flashlights are generally powered by lead batteries, and usually end their life after about one year of use. The reason is that the battery cannot be charged. Most of the time, the electrolyte inside the battery is dry, or the battery is over discharged. So what if a rechargeable flashlight doesn’t charge? The simplest way is to find a good fully charged battery, and the overdischarge battery, positive and negative corresponding directly connected, to charge the overdischarge. Let’s take a look at the reasons why the rechargeable flashlight can’t be charged and the solutions!

First.Why can’t the rechargeable flashlight charge into the electricity    

    The battery is bad, the general market led flashlight battery is lead acid battery. Charging circuits are power-frequency transformer with simple rectifier, or a series of plastic capacitance rectifier.

    The fatal disadvantage is that it can not automatically stop charging after filling, nor can it be constant current and voltage limiting. After several long recharges, the battery was wiped out.

    Charging time is too short, it will also cause battery undercharge, plate vulcanization damage. There is no loss of power detection circuit, battery discharge can not automatically cut off the power supply caused by battery overdischarge damage.

    A good flashlight is lithium battery, charger, LED drive circuit with CB and other safety regulations and environmental protection certification. he battery is bad, the general market led flashlight battery is lead acid battery. Charging circuits are power-frequency transformer with simple rectifier, or a series of plastic capacitance rectifier.

Second.Rechargeable flashlights often fail

    1. The flashlight circuit is broken

The internal wiring is broken, the brass spring conductive piece inside the plug is deformed, and the broken line is connected or the spring piece is deformed.

    2. Electronic components of charging circuit are damaged

Check the step-down capacitor and rectifier diode. Replace damaged components.

    3. Rechargeable batteries fail

One is lead-acid batteries, whose plates tend to age. Clean the plate, replace the distilled water (or pure water, less effective.) . Some can be repaired.

    The other uses nickel metal hydride batteries, or cadmium nickel batteries. This kind of battery life may not expire, but because of memory effect and charge into the electricity, this situation is not fully charged, discharge caused by the use of more. At this time, the battery can be discharged, need to add discharge current limiting resistance, and then charge, part can be repaired.

Third.What should I do if I can’t charge the rechargeable flashlight

    The simplest way is to find a full charge of a good battery, and put the battery, positive and negative corresponding directly connected, to put the charge, if the voltage can rise, and then use the charger to charge on the line, if not ，I recommend you to change it.

Fourth.Rechargeable flashlight maintenance measures

    1. Do not lose power when storing

The state of power loss means that the battery is not charged in time after use. The longer the battery is idle, the more damaged the battery is.

    2, do not expose

Do not expose to the sun. If the temperature is too high, the environment will increase the internal pressure of the battery, so that the battery pressure limiting valve is forced to open automatically, the direct consequence is to increase the water loss of the battery, and the battery excessive water loss will lead to a decline in battery activity, accelerate the softening of the plate, charging the drum, shell heating, deformation and other fatal damage.

    3. Regular inspection

In the process of use, if the discharge time drops suddenly, it is likely that at least one battery in the battery pack appears broken grid, plate softening, plate active substances fall off short circuit phenomenon. At this time, should be timely to the professional battery repair agency for inspection, repair 4, complex and match group

Instantaneous high-current discharge should be avoided, which may easily lead to lead sulfate crystallization and damage the physical properties of the battery plate.

    5. Correctly grasp the charging time

In the process of use, should grasp the charging time according to the actual situation, the general battery is charged at night, the average time is about 8 hours. The battery will be fully charged soon. If you continue to charge the battery, overcharge will occur, resulting in water loss and heat, which will reduce the life of the battery. Therefore, the battery to discharge depth of 60%-70% when a charge.

    6. Avoid pulling the hot plug when charging

If the output plug of the charger is loose and the contact surface is oxidized, the charging plug will become hot. If the heating time is too long, the charging plug will short circuit, which will directly damage the charger and cause unnecessary losses. So when the above situation is found, the oxide should be removed or replaced in time.