18650 lithium battery has high energy density, so most of it is used in laptop battery. In addition, because 18650 has very good stability in work, it is widely used in various electronic fields. Commonly used in high-end glare flashlights, portable power supplies, wireless data transmitters, electric heating suits, shoe materials, portable instruments, portable lighting equipment, portable printers, industrial instruments, medical instruments, etc.
So how to choose a high-quality 18650 lithium-ion battery? Choose the 18650 lithium battery that is most suitable for you according to the electrical equipment, such as the appropriate brand, voltage, capacity, continuous discharge rate, battery life, etc. The most important thing is to choose a battery with high safety. Below we will introduce in detail one by one.
In terms of brands, there are internationally well-known brands such as Sanyo, Samsung, SONY and LG that are more reliable. Sanyo and LG focus on conventional applications, and their applications are mainly glare flashlights, mobile power supplies and laptop batteries. SONY focuses on high-current power supplies. Take VTC4 as an example, the discharge current can reach 30A, electronic cigarettes, toys, etc., easy to handle.
2. Nominal capacity
The nominal capacity of the 18650 battery is related to the endurance. The higher the capacity, the stronger the endurance. For example, a 2800mAh battery can be continuously discharged for 2 hours at 1.4A.
3. Continuous discharge current (CDR)
The continuous discharge capacity is represented by C. For example, the capacity of an 18650 battery is 2800mAh and the continuous discharge capacity is 0.5C, so the continuous discharge current is 1.4A. Discharging over 1.4A for a long time will seriously affect the battery life, and there may be dangers such as overheating, burning, and explosion.
4. Internal resistance
The smaller the internal resistance, the lower the consumption and the stronger the discharge capacity. The internal resistance parameter will generally be written on the battery introduction page. Please pay attention when buying, try not to buy batteries above 100mΩ. If multiple 18650 batteries are used in series, batteries of the same brand and model must be purchased, otherwise batteries with large internal resistance and low capacity will become disadvantages.
Temperature is a major factor affecting the life of 18650 lithium batteries. The higher the temperature, the more the battery will age. The higher the temperature, the greater the internal damage of the battery.
6. Pointed and flat
The pointed 18650 battery has a protective plate, and the flat 18650 battery does not have a protective plate. The 18650 lithium battery with a protective plate is several millimeters higher than the 18650 lithium battery without a protective plate, and the price is slightly more expensive, but it is safer and more versatile. The 18650 lithium battery has a protective plate to prevent the battery from over-discharging. Excessive discharge of the battery will cause the lithium battery to heat up, or even burn or explode.
Among all 18650 lithium-ion batteries, LiSOCl2 has the highest energy density, with the longest life span of 15-20 years. This type of battery is particularly suitable for devices with relatively short supply currents.