How To Choose High-Quality 18650 Lithium Battery? | IMREN Battery

According to our electrical equipment, choose the 18650 lithium battery that is most suitable for us, such as the appropriate brand, voltage, capacity, continuous discharge rate, battery life, etc. The most important thing is to choose the battery with high safety. Now we will give a detailed introduction one by one:

1. Nominal capacity
The nominal capacity of the 18650 battery is related to the endurance capacity. The unit is "mAh". The higher the capacity, the stronger the endurance capacity. For example, the 2800mAh battery can discharge continuously for 2 hours at 1.4A current.

2. Continuous discharge current (CDR)
Continuous discharge capacity is expressed by C number, and continuous discharge current=continuous discharge capacity C number × Capacity.

For example, if the capacity of a 18650 battery is 2800mAh and the continuous discharge capacity is 0.5C, then the continuous discharge current is 1.4A. If the battery is discharged over 1.4A for a long time, the battery life will be seriously affected, and there may be overheating, even burning, explosion and other risks.

3. Internal resistance
Internal resistance is the resistance of the battery itself. The smaller the internal resistance is, the lower the consumption is, and the stronger the discharge capacity is. The internal resistance parameter will also be written on the battery introduction page. Pay attention to it when purchasing, and try not to buy more than 100m Ω cells.

When using multiple 18650 batteries in series, you must buy batteries of the same brand and model, otherwise the batteries with large internal resistance and low capacity will become short boards.

4. Temperature
Temperature is a major factor affecting the life of the 18650 lithium battery. The higher the temperature, the faster the battery will age. The higher the temperature, the greater the damage the battery will suffer.

5. Pointed and flat head
The 18650 lithium battery also has a flat head and a pointed head. As shown in the figure below, the protruding part of the positive pole on the left is the pointed head, and the protruding part of the positive pole on the right is the flat head.

In general, I recommend to buy a pointed battery to ensure that it can be compatible with more devices and applications. Generally, the positive and negative poles of the flashlight are designed with springs, which can be retracted. Both the pointed and flat batteries can be used. However, if the flat-head battery is to be used in series, the positive pole of the flat-head battery cannot contact the negative pole of the other battery.

6. With and without protective plate
Pointed 18650 with protective plate, flat 18650 without protective plate.

The 18650 lithium battery with protective plate is several mm higher than the 18650 lithium battery without protective plate, and the price is a little more expensive, but the safety is higher and the versatility is stronger. The 18650 lithium battery with protective plate can prevent the battery from over-discharge, which will cause the lithium battery to heat, even burn, explode and other dangers.