What are the common faults of lithium battery pack protection boards?

Repair methods and common faults of lithium battery protection boards. The extent of damage to a lithium battery protection board depends on the degree of damage and the value of repair. As the name suggests, a lithium battery protection board is used to protect lithium batteries. Its function is to protect the battery from over-discharge, overcharge, overcurrent, and also to prevent output short circuits. How to repair a damaged lithium battery protection board?

If the protection board of a lithium battery is broken, you can first charge it with a charger to see if it can activate the protection board. If you can't fill it up, it must be broken. It could be that the electronic components are damaged, or it could just have been reset! But if the protection board is broken, the measured value should be 0V. If you have come into contact with lithium battery protection boards, let's discuss why lithium battery protection boards do not have charge and discharge protection. I hope this can bring you some useful help.

Under what circumstances does a lithium battery protection board not provide charge and discharge protection?

First, let's look at the ternary parameters: lithium and iron are respectively 2.8 - 4.25 and 2.5 - 3.65 V.

It might be due to overcharging, overdischarging, overcurrent, short circuit or overheating.

2. Use a multimeter to measure whether the charging and discharging MOSFETs are open-circuited.

If the lithium battery protection board is equipped with an LED, the LED will flash for 0.5 seconds to give an alarm when charging and discharging are not allowed.

4. If the lithium battery protection board is equipped with an upper computer, it can be connected to the upper computer to check the protection status.

5. The lithium battery protection board is equipped with a weak point switch. Please check if the weak point switch is turned on.

In these cases, you can check the following methods to fix:

Overcharged, over-discharged, overcurrent, or short-circuited batteries should be inserted into the charger for recycling.

2. Overcurrent disconnection and load recovery

What is a lithium battery protection board?

A lithium battery protection board provides charge and discharge protection for series lithium battery packs. After being fully charged, it ensures that the voltage difference between individual cells is less than the set value, allowing all cells in the battery pack to be charged evenly and effectively improving the charging effect in a series charging mode. At the same time, it detects the overvoltage, undervoltage, overcurrent, short circuit, and over-temperature conditions of each individual cell in the battery pack to protect and extend the battery's service life. Undervoltage protection prevents each individual cell from being damaged due to over-discharge during the discharge process.

The protection function of lithium batteries is usually accomplished by the cooperation of protection circuit boards and current devices such as PTC. The protection board is composed of electronic circuits and can accurately monitor the cell voltage and charge/discharge circuit current at any time in an environment ranging from -40 to 85 degrees, and promptly control the on and off of the current circuit. PTC can prevent the battery from being severely damaged in high-temperature environments.

Common lithium battery protection boards typically include control ICs, MOS switches, resistors, capacitors, and auxiliary components such as fuses, PTCs, NTCs, ID, and memory. Among them, the control IC keeps the MOS switch on under all normal conditions, connecting the battery cell to the external circuit. When the battery cell voltage or circuit current exceeds the specified value, it immediately turns off the MOS switch to protect the battery cell's safety.

The principle of lithium battery protection board:

The reason why lithium batteries (rechargeable) need protection is determined by their own characteristics. Due to the material of lithium batteries themselves, they cannot be overcharged, over-discharged, overcurrent, short-circuited or charged and discharged at extremely high temperatures. Therefore, a delicate protection board and a current fuse are always present in lithium battery packs.

The protection function of lithium batteries is usually accomplished by the cooperation of protection circuit boards and current devices such as PTC. The protection board is composed of electronic circuits and can accurately monitor the voltage of the battery cells and the current of the charging and discharging circuits at any time in an environment ranging from -40 to 85 degrees Celsius, and promptly control the on and off of the current circuit. PTC can prevent the battery from being severely damaged in high-temperature environments.

Common lithium battery protection boards usually include control ICs, MOS switches, resistors, capacitors, and auxiliary devices such as fuses, PTCs, NTCs, IDs, and memory. Among them, the control IC controls the MOS switch to be on under all normal conditions, connecting the battery cell to the external circuit. When the battery cell voltage or loop current exceeds the specified value, it immediately controls the MOS switch to be off to protect the battery cell's safety.