How to repair 18650 lithium battery charger

The 18650 type lithium battery is the most commonly used lithium battery in electronic products. There are portable fans, bright flashlights, and even cars in notebook batteries, power bank batteries. First of all, we first disassemble the charger, there are three screws on the back, which are easy to disassemble. Carefully observe the circuit board components, there is no abnormal smell, burnt phenomenon, the board is very clean, so now it can only be measured step by step. Preparation tools: multimeter, screw set, desktop vise (clamp the circuit board to facilitate desoldering), solder paste, solder wire. Now start to measure. Here is a brief introduction to my own test methods for the quality of each component. Resistance: First set the multimeter range to 200k, regardless of the positive and negative poles, and connect the test leads to both sides of the resistance. Observe that the multimeter can have a reading. If there is a reading, there is no problem. If there is no reading, increase the range. If it is adjusted to the maximum, there is still no The reading proves that the resistance is open circuit, and the resistance of the same specification should be replaced. Capacitor: First set the multimeter range to the continuity test position, and connect the test pen to the two ends of the capacitor casually. Observe whether the reading has an increasing value, and when the position cannot be read, it is good to exchange the positive and negative poles of the test pen to have the same phenomenon. of. Otherwise it has been broken down. Ordinary diode: The diode is divided into positive and negative poles, the forward conduction is conducted, and the reverse conduction is not. Therefore, use this property to perform good or bad detection. The on-off test can also be used for the ohm test. Triode: I tested the quality of the triode in this way. It is divided into pnp and npn, so first set the multimeter to the ohm range, then put the red test pen in the middle, and measure the black test pen on both sides to see if there is any resistance. If there is no resistance, put the black test lead in the middle, and measure the red test lead on both sides. If these two types have no resistance, then this triode should be problematic. Of course, it can also be detached and inserted into the triode measurement interface of the multimeter for direct measurement, which is just a bit more troublesome. Note: When you test a component that has an abnormality, do not directly purchase and replace it, because the measurement result in the circuit may be inaccurate, you must remove it and measure it to determine whether it is good or bad! In order to avoid tossing for a long time to buy or search for the component and then the replacement is not fixed. The problem is because the components are not broken. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Where are the disadvantages of lithium batteries?