Industry News

What are the misunderstandings of 18650 batteries

2022-03-02
People really don't know much about 18650 batteries, and they have never even heard of the name. They don't even know that these 5 numbers represent a kind of battery, because 18650 batteries are used more in industry, but few in civilian use. Most of them are used in notebook batteries, in addition, they are also commonly used in high-level glare flashlights and mobile power supplies that were popular at the time. However, with the frequent explosion of mobile power supplies, 18650 has also begun to enter people's attention. People have begun to know about 18650 batteries, and they have also begun to misinterpret it.
Misunderstanding 1: 18650 is not safe, simple blasting
The 18650 that we often talk about actually refers to the shape standard of the battery. It is a standard battery model set by the Japanese company SONY in order to save costs. 18 means the diameter is 18mm, 65 means the length is 65mm, and 0 means the cylindrical shape. Battery. 18650 batteries originally referred to nickel-hydrogen batteries and lithium-ion batteries. Because nickel-hydrogen batteries were rarely used at the beginning, they mostly referred to lithium-ion batteries. The nominal voltage of 18650 lithium-ion battery single cell is: 3.6V or 3.7V; the end-of-discharge voltage is: 2.75V. The common capacity is 1200-3100mAh, and higher than 3400mAh is basically a false standard.
The 18650 battery has been around for a long time since it was introduced by Sony in the 1990s. 18650 batteries are widely used in industrial fields and electronic equipment such as notebook computers, walkie-talkies, instruments and meters because of their large capacity, high energy storage efficiency, good firmness, no recall effect, high cycle life, and no toxic substances. The recent hot Tesla electric car also uses the 18650 battery pack provided by Panasonic.
Most 18650 batteries are encapsulated in steel casings. Because the batteries with poor quality do not maintain their functions, their internal pressure will increase sharply when overcharged (moderately charged), and they will burst when they exceed the acceptable value. Problems such as short circuit, high temperature, or the battery being squeezed and deformed or even punctured may cause the battery to burst. After 30 years of development, the 18650 battery preparation process has been very mature. In addition to the improvement in function, its insurance is also very good. In order to avoid the explosion of the sealed metal casing, the 18650 battery was originally equipped with a safety valve on the top. The safety valve is the standard configuration of each 18650 battery and is also an important explosion-proof barrier. When the internal pressure of the battery is too large, the top safety valve will open the exhaust to reduce pressure to avoid explosion. However, when the safety valve is opened, the chemical substances leaked from the battery will react chemically with the oxygen in the air under the premise of high temperature, and there is still a possibility of a fire. In addition, some 18650 batteries also have their own maintenance boards, which have functions such as overcharge and overdischarge and short circuit maintenance, and the insurance function is very high.