CR2477 battery

Why do CR2477 battery need protection boards?

Because overcharging, overdischarging, and short-circuiting of CR2477 battery may cause the battery to be scrapped, and the protection board is used for this protection. If you can ensure that the battery is not overcharged, overdischarged, or short-circuited during use, you can do without the protection board. During the use of CR2477 battery, every overcharge, overdischarge, and short-circuit will reduce the battery life. In severe cases, the battery will be directly scrapped! If there is no lithium-ion battery protection board, the lithium-ion battery will be directly short-circuited and overcharged, which will cause the battery to swell, and in severe cases, leakage, decompression, explosion, or fire will occur.

The protection board is to ensure safety and CR2477 battery are not considered to be overcharged or over-discharged, because the previous lithium-ion battery overcharge and over-discharge will cause battery damage or explosion, fire and other dangers. Therefore, when CR2477 battery were launched, protection boards also appeared. Recently, with the emergence of lithium iron phosphate CR2477 battery, it is claimed that lithium iron phosphate CR2477 battery are not afraid of overcharge or over-discharge, so there is an argument that it is okay not to add a protection board. However, as of now, there has been no battery manufacturer that publicly claims not to use a protection circuit. The protection board is the purpose of a bodyguard. The protection board is to ensure the safety of CR2477 battery.

Of course, if the lithium-ion battery protection board is not designed well, it will also damage the battery, but the purpose of the protection board is to protect the battery and prevent the battery from having safety problems. So it is better to use it now. When the lithium-ion battery is really not afraid of overcharge or over-discharge, consider not using the protection board!

The function of the lithium-ion battery protection board is mainly to protect the cells of the rechargeable battery, maintain the safety and stability of the battery during charging and discharging, and play an important role in the performance of the entire battery circuit system.

1. Overcharge protection function: Overcharge protection function means that when a certain voltage (hereinafter referred to as overcharge test voltage) is reached, the charger is prohibited from continuously charging. That is, the MOS tube that controls overcharge is turned off and charging is stopped.

2. Overdischarge protection function: The overdischarge protection function stops discharging to the load when the voltage of the lithium-ion battery becomes low. The MOS tube that controls overdischarge is turned off and its discharge is prohibited. This process is exactly the opposite of the action during the overcharge test.

3. Overcurrent protection function: The overcurrent protection function stops discharging to the load when a large current is consumed. The purpose of this function is to protect the battery and MOS tube and ensure the safety of the lithium-ion battery in the working state. After the overcurrent test, the battery will return to normal after being separated from the load and can be charged or discharged again.

4. Short-circuit protection function: In addition to the control IC, there is another important component in the circuit, which is MOSFET. It plays the role of a switch in the circuit. Since it is directly connected in series between the battery and the external load, its on-resistance affects the performance of the battery. When the selected MOSFET is good, its on-resistance is very small, the internal resistance of the battery pack is small, the load capacity is strong, and the power consumption during discharge is also small. When your battery is accidentally short-circuited, the protection board will automatically close within a few milliseconds and will not be powered on. At this time, it is okay even if the positive and negative poles touch each other.

The lithium-ion battery protection board is the charge and discharge protection for the series lithium-ion battery pack; when fully charged, it can ensure that the voltage difference between each single cell is less than the set value (usually ±20mV), realize the equalization of each single cell of the battery pack, and effectively improve the charging effect under the series charging mode; at the same time, the overvoltage, undervoltage, overcurrent, short circuit, and overtemperature of each single cell in the battery pack are tested to protect and extend the battery life; undervoltage protection prevents each single cell from being damaged due to over-discharge during discharge.

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