The best 18650 lithium battery pack
The numbers 18650 in the 18650 lithium battery represent the appearance size: 18 means a diameter of 18mm, 65 means a length of 65mm, and 0 means a cylindrical battery. It is a standard lithium-ion battery model set by Japan’s SONY company in order to save costs, called 18650 lithium battery.
18650 lithium battery pack usually consists of three parts: 18650 cells, protection board (usually called PCBA) and shell structure. The best 18650 lithium battery pack should choose the best of the following three components:
1.Using high-quality 18650 batteries
The best 18650 lithium battery pack should be composed of first-line brand cells, and the mainstream capacity ranges from 1800mAh to 3500mAh. The single cell has undergone a series of safety tests and performance tests. After years of quality evaluation, high-quality batteries recommend the following:
Global first-line brand 18650 batteries: SAMSUNG, PANASONIC, LG, SANYO, SONY
China’s first-line brand 18650 batteries: Keheng, Lishen, BAK, etc.
2.Multifunctional protection circuit board (PCBA)
The core component of the lithium battery protection board is the protection IC. The main materials of the protection board are PCB, magnetic field effect transistor (MOS tube), NTC, PTC, capacitor, resistor, diode, triode, etc.
Overcharge protection: When the voltage of a certain string of the battery pack is greater than the maximum value (overvoltage) and the protection delay is reached, the IC controls the CMOS to turn off the charging circuit.
Over-discharge protection: When the voltage of a certain string of the battery pack is less than the maximum value (under-voltage), and the protection delay is reached, the IC controls the DMOS to turn off the discharge circuit.
Over-current and short-circuit protection: When the output current of the battery pack P+ and P- exceeds the over-current/short-circuit current value and reaches the over-current/short-circuit delay, the control circuit controls the discharge DMOS to turn off the discharge circuit and stop discharging.
High and low temperature protection: When the temperature sensor reaches the temperature threshold and reaches the protection delay, the control circuit controls the charge and discharge MOS tube to turn off and stop the charge and discharge.
The lithium battery protection board also has the functions of power detection, remaining capacity display, battery working status display, communication remote control and other functions.
3.Shell structural parts
According to the needs of electrical appliances, design a matching shell structure, usually plastic shell, metal shell, simple PVC heat shrink, etc.
4.Exquisite lithium battery PACK process
For the 18650 lithium battery pack, the superb PACK capability is very important. It is necessary to have advanced equipment, skilled technical workers, a mature management model, and strict production requirements to ensure that the 18650 lithium battery pack can be welded, tested, There will be no omissions in important links such as aging and pre-shipment testing, and the best 18650 lithium battery pack will be produced.
High quality 18650 11.1V 6000mAh low temperature lithium battery for special electromagnetic spectrometer
Product number: 17AQ022-01
Cell model: 18650/11.1V/2000mAh
Battery specification: 18650-3S3P/11.1V/6000mAh
Product size: 173×77×20mm (Max)
Working temperature: -40℃~+60℃
Lithium battery protection: short circuit protection, overcharge protection, overdischarge protection, overcurrent protection.
Shockproof and waterproof: The shockproof structure design is filled inside the fireproof PC shell to meet the requirements of high safety and high reliability;
Low temperature work: low temperature batteries are used to ensure that it works at a low temperature of -40 degrees.
Reliable connection: Gold-plated to gold finger connectors, fast, safe and reliable;
The battery pack is safe, with a temperature probe, which can upload temperature information to the host computer;
Battery pack I2C communication, can upload battery voltage, current, capacity and other parameters to the host computer;
The battery pack has a high cycle life and is in line with the value concepts of low carbon, energy saving and environmental protection;
the best electronic cigarette 18650 lithium battery
Most e-cigarettes use lithium-ion batteries as their power source. Battery life depends on battery type and size, usage and operating environment. And there are many different types of battery chargers to choose from, such as socket direct charging, car chargers, and USB interface chargers. At present, the electronic cigarettes on the market use the highest proportion of 18650 lithium batteries.
Conventional electronic cigarette 18650 lithium battery model
- Sony VTC4 (20 to 30 A / 2100 mAh)
- Sony VTC5A (25 to 30 A / 2500 mAh)
- Sony VTC6 (20A / 3,000mAh)
- Samsung INR18650-20S (30 A / 2000 mAh)
- Samsung INR18650 20R (22 A / 2000 mAh)
- Samsung 25 R (20 A / 2500 mAh)
- Samsung INR 18650-30Q (20 A / 3000 mAh)
- LG HD2C (25A / 2200mAh)
- LG INR 18650HG2 (20A/3000mAh)
- LG 18650 HE2/HE4 (20A/2500mAh)
How to choose high-quality 18650 lithium battery?
Choose the most suitable 18650 lithium battery according to our 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 them in detail:
As for brands, the most reliable ones are Sanyo, Samsung, SONY, LG and other internationally renowned brands.
Sanyo and LG focus on routines, and their applications are mainly bright flashlights, power banks, and laptop batteries.
SONY professional, the main power and high current. Taking VTC4 as an example, the discharge current can reach 30A, and it can easily handle electronic cigarettes, toys, etc.
The nominal capacity of the 18650 battery is related to the battery life. The unit is “mAh“. The higher the capacity, the stronger the battery life. For example, a 2800mAh battery can be continuously discharged for 2 hours at a current of 1.4A.
Continuous Discharge Current (CDR)
Continuous discharge capacity is expressed by C number, continuous discharge current = continuous discharge capacity C number × capacity.
For example, the capacity of a 18650 battery is 2800mAh and the continuous discharge capacity is 0.5C, then the continuous discharge current = 1.4A. If the discharge exceeds 1.4A for a long time, the battery life will be seriously affected, and there may be dangers of overheating, even burning, explosion, etc.
The internal resistance is the resistance of the battery itself. The smaller the internal resistance, the lower the consumption and the stronger the discharge capacity. The parameter of internal resistance is generally written on the battery introduction page. You should also pay attention to it when purchasing. Try not to use it. Buy more than 100mΩ or more cells.
If you use multiple 18650s in series, you must buy batteries of the same brand and type, otherwise batteries with large internal resistance and low capacity will become a short board.
Temperature is a major factor affecting the life of 18650 lithium batteries. The higher the temperature, the faster the battery will age. The higher the temperature, the greater the damage inside the battery.
pointed and flat
The 18650 lithium battery also has a flat head and a pointed head. The positive electrode on the left side of the figure below has a protruding point, and the positive electrode on the right has no protrusion. It is a flat head.
In general, I recommend buying pointed batteries to ensure compatibility with more devices and uses. Usually, the positive and negative poles of the flashlight are designed with springs, which can be retracted and can be used whether it is a pointed or flat battery. But if you want to use a flat head battery in series, the positive pole of the flat head cannot touch the negative pole of the other battery.
With and without BMS
The pointed 18650 has a Simple protective BMS, and the flat 18650 does not have a simple protective BMS
The 18650 lithium battery with a protective plate is a few mm 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 with a protective plate can prevent the battery from being over-discharged. Lithium batteries are hot, and even dangerous to burn and explode.
How to avoid buying fake 18650 lithium batteries?
When we buy 18650 lithium batteries, we will inevitably encounter a lot of fake products on the market. How should we avoid buying fake and shoddy products?
- Choose high-quality suppliers
- Check the workmanship of the battery. The genuine lithium battery shell is made of special materials, which is very strong, and has a neat appearance without unnecessary burrs. The outer surface has a certain roughness and feels comfortable, and the inner surface feels smooth.
- Pay attention to checking brand trademarks, commodity certificates, testing certificates, etc.
The lithium battery label adopts secondary printing technology. Under certain light, from the side, it is obvious that the color of the barcode part is darker than the rest.
- Battery performance test, to ensure that the battery performance passes the test.