Negative pulse battery maintenance device

This electric vehicle battery maintainer is a negative pulse generator with a simple structure and easy to make. It can absorb the electric energy of the battery and convert it into a pulse voltage much higher than the battery voltage to maintain the battery. This negative pulse is used to eliminate Vulcanization on the battery plates.

The principle of the device is shown in the figure. The working process is as follows: the battery voltage charges C1 and C2 through R1, L1, R2, and L2. When the voltage at both ends of the trigger diode reaches its trigger voltage, the trigger diode conducts, and the voltages on C1 and C2 are connected in series to form a voltage higher than the battery voltage. A pulse with the same polarity. Because the impedance of L1, R1 and L2, R2 to the pulse is much greater than that of the battery, this pulse current is basically released through the battery to repair the sulfide on the plate. When the voltage across the diode is insufficient to maintain its conduction, the trigger diode is cut off and the circuit proceeds to the next charging cycle.

Pay attention to the selection of components here: because the key to this device is whether the trigger diode can continuously conduct and cut off, which depends on its trigger voltage and the battery voltage that needs to be maintained. If the battery voltage is 36V or 48V, you can directly use the bidirectional trigger diode DB32 on the dimming desk lamp circuit board without polarity restrictions. If the battery voltage is 12V or 6V, you can connect several batteries in series to repair it, or use a trigger diode corresponding to the trigger voltage. Inductors Ll and L2 can use the mutual induction coil in the leakage protector, or the magnetic core high-frequency choke coil on the waste energy-saving lamp circuit board. Capacitors C1 and C2 should be selected with a withstand voltage of 63V. The size of the capacity determines the frequency and intensity of the pulse. A small capacity has a higher frequency, a large capacity has a lower frequency, but the pulse; medium intensity is higher. Generally, it is selected between 22μF and 100μF. It should not be chosen too large. Excessive capacity will cause the discharge current to be too large and burn out the trigger diode. The resistor power of R1 and R2 is 0.5W. The resistance value is generally selected between 2kΩ and 5kΩ. If it is too small, the trigger diode cannot be cut off after it is turned on. If it is too large, the charging time of capacitor Cl and C2 will be extended, and the pulse frequency will become lower, which will extend the repair time. .

After assembly, the battery can be connected for testing. Use a multimeter with a 50V DC voltage range to measure the voltage across the trigger diode. If the multimeter pointer keeps shaking when it is lower than the power supply voltage, it means that the device has generated pulse voltage and is working normally. If the pointer does not shake at a place lower than the power supply voltage, it may be that the resistance of the resistors Rl and R2 is too low to prevent the trigger diode from cutting off or the trigger diode itself is faulty; if the measured voltage is the power supply voltage and the needle does not shake, it means that the trigger diode has triggered The voltage is too high or the battery voltage is too low. The device itself consumes very little current and can be connected to the battery for long-term maintenance work.