The Safety Valve for 18650 Lithium Battery
What is the 18650 lithium battery safety valve?
The function of the 18650 safety valve
When the pressure inside the lithium battery reaches a set value, then the valve is lifted up and the circuit is disconnected to avoid danger. It is somewhat similar to the principle of a pressure cooker safety valve. The safety valve of the lithium battery leaks mainly because of the overly high internal pressure. And the high pressure is often caused by the high charging voltage. So for safety, please replace the battery of the same model.
The 18650 lithium battery production process has been very mature. In addition to its performance has been greatly improved, its safety is also very complete. In order to avoid explosion of the sealed metal casing, 18650 batteries are now equipped with a safety valve on the top. The safety valve is the standard configuration of every 18650 battery and the most important explosion-proof barrier. When the internal pressure of the lithium battery is too high, the safety valve on the top of the lithium battery will open the exhaust and reduce pressure to avoid explosion.
However, after the safety valve is opened, the chemical substances leaked from the 18650 lithium battery will react chemically with oxygen in the air under high temperature conditions, and a fire may still occur. Now, some 18650 lithium batteries come with their own protection boards, which have functions such as overcharge, overdischarge and short circuit protection. And that has ensured their high safety performance.
Can the safety valve prevent explosion?
Most 18650 lithium batteries are encapsulated in steel shells. Some poor quality batteries without protection will explode under the condition of overcharge beacuse the internal pressure increases sharply and exceeds the withstand value. Problems like short circuit, high temperature or squeezed deformation or even puncture of the battery may cause the explosions.
If the internal pressure of the lithium battery increases, the safety valve will burst to release the internal pressure to avoid the battery explosions. Generally, the positive electrode of the cylindrical battery has a safety valve.
The regular and qualified 18650 lithium battery is very safe. Although the manufacturer uses some safety measures for the lithium ion battery, we must pay special attention to it when using the battery. For devices with replaceable batteries, use the original battery as much as possible. At the same time, we should maintain ventilation and heat dissipation when charging, especially mobile phones And it is best not to charge on the bed, so as to avoid heat buildup and cause the lithium battery explosions.
The high-capacity power lithium battery safety valve includes a valve body, wherein the valve body includes an upper valve body and a lower valve body. The lower valve body has an exhaust passage, while the upper valve body has a cavity structure. The exhaust passage is in communication with the cavity of the upper valve body. And the upper end of the upper valve body cavity is provided with an upper top that can be rotatably connected with the upper valve body. While a lower top is set at the lower end of the cavity. The upper top and the lower top are connected by elastic elements.
A sealing rubber gasket for sealing the exhaust passage is fixed on the lower top. An exhaust hole for exhaust is on the side wall of the upper valve body. Meanwhile, the contact position of the valve body and the sealing rubber gasket is set in a circle. The arc structure further enhances the sealing performance of safety valve and the stability of pressure relief. And it can still ensure timely and effective discharge of the gas in the battery when a large amount of gas is generated inside the battery. Besides, the safety valve has higher stability and safety, with a simple structure and a low production cost.