The method is as follows:
1. Check the abnormal performance of the protection board. No flicker, low output voltage, inability to support load, no short circuit protection, no self-recovery short circuit protection, large internal resistance, etc. may be symptoms of protection board malfunction.
2. Make sure the sample line (flat cable) is connected correctly and use a multimeter to make sure the battery cable is connected correctly.
3. Measure the voltage of each battery string. The lithium voltage should be 3.0-4.2V; the voltage of lithium iron phosphate is about 2.0-3.6V and that of lithium titanate is about 1.5-2.75V; . If the voltage on a string differs by more than 2 V, this means that the ribbon cable is not connected correctly and must be reconnected.
4. Measure the resistance between B- and P- of the protection board. If the resistance is 0, it means they were not obstructed before and the shield is good. Or by connecting line B, measure the voltage between B- and the total positive electrode of the battery and the voltage between P- and the total positive electrode of the battery. If the voltage is constant, it means the protection board is normal.
What should I do if the 4812 lithium battery protection board has no power?
Actually, it depends on how long the battery has been used and the power of electric hand drills. is relatively large, and the discharge current is also large. It's easy to get old. If used for a long time or frequently, it is not recommended to repair the protection board and directly replace the battery. Lithium batteries for electric hand drills are foundusually in a housing with metal contacts that are directly plugged in. If there are alternative lithium batteries on sale, it is very convenient to purchase just one.
How to repair electric vehicle lithium batteries
Directly charge the lithium battery without passing through the protection plate, that is, directly charge B+ and B- lithium battery though. it can be charged, that is, it can rest assured that it is normal for the lithium battery not to pass through the protective plate.
Replace the protection panel. If the new protection board is replaced and the battery can be charged, but the old protection board cannot be charged, it means that the protection board of the previous lithium battery is defective.
If it is a problem with the lithium battery protection board, most of the time it is because the MOS ofThe charging protection board is defective, or the charging fuse is broken by large current, or the integrated circuit of the lithium battery protection board is damaged.
Solution: The lithium battery protection board fails, causing the lithium battery to fail to charge. The most direct solution is to replace the protection board with a new one.
If there is no completely new protection board, you can detect the specific fault points of the protection board, such as MOS tubes, resistors, capacitors, circuits Built-in fuses, fuses and other components, detect the specific fault points of the protection board, and then compare them accordingly.
Lithium batteries of electric vehicles are generally composed of at least ten lithium batteries connected in series, with internal battery protection boardsegrees. They are completely different from lead acid batteries (which are). (small number and usually without a protective panel), if a fault occurs, non-professional technical personnel generally cannot solve it.
Damage to electric vehicle lithium batteries generally includes the following situations:
1. The battery protection panel is damaged and the electronic components inside are densely packed, making it generally difficult to operate. to repair;
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2. The battery protection panel is in good condition. If the performance of a single battery deteriorates, it is not easy to find it;
3. If some batteries are shorted, go investigate;
In short, after an electric vehicle lithium battery fails, it is generally difficult to repair it by the after-sales service, and the manufacturer's technicians will solve it.t the problem or replace the lithium battery of the same model of electric vehicle.
Detailed information:
1. Charge it every day. Even if the lithium battery in your electric vehicle can last 2 to 3 days on a single charge, it is still recommended to recharge it daily. Since the used lithium battery is in a shallow cycle state, charging it daily will extend the life of the electric vehicle lithium battery.
2. Charge on time. Since lithium batteries will enter the sulfidation process after being discharged, if charged in time, less serious sulfidation can be eliminated. Therefore, lithium batteries should be charged as soon as possible after use to keep the battery as full as possible.
3. Regular deep discharge. A regular deep discharge of thebattery is also beneficial for "activating" the battery, which can increase battery capacity slightly. The general method is to completely discharge the battery regularly.