Explanation of Standard Specifications for 18650 Lithium ion Batteries and Cylindrical Lithium ion Batteries.
Introduction to 18650 Lithium Battery
18650 lithium battery is a standardized cylindrical lithium-ion battery named after its size specifications - diameter 18 millimeters (18mm) and length 65 millimeters (65mm), with the final "0" table
It is a cylindrical battery. This type of battery was first commercialized by Sony in the early 1990s and became a standard model in the industry, widely used in various electronic products
And in the equipment.
18650 lithium batteries have the following characteristics:
High energy density: Compared to traditional batteries of the same volume, 18650 lithium batteries can store more electrical energy and have a higher specific energy.
Rechargeability: Lithium ion batteries support hundreds to thousands of charge and discharge cycles, reducing the cost of long-term use.
Multiple chemical systems: Common 18650 batteries include various positive electrode material systems such as lithium cobalt oxide (LiCoO2), lithium manganese oxide (LiMn2O4), nickel cobalt manganese ternary (NMC), as well as graphite
The main negative electrode material may vary in voltage, capacity, safety, and other aspects according to different chemical formulas.
Voltage parameters: The standard
18650 lithium-ion battery has a nominal voltage of approximately 3.7V, a charging cut-off voltage of 4.2V, and a discharging cut-off voltage ranging from 2.5V to 3.0V depending on the chemical system. phosphorus
The voltage range of lithium iron phosphate (LFP) 18650 batteries is slightly different, with a nominal voltage of 3.2V and a charging cut-off voltage of 3.6V.
Capacity range:
The capacity of 18650 lithium batteries ranges from 1000mAh in the early days to 3000mAh or even higher now, with mainstream product capacities concentrated between 2200mAh and 3400mAh.
Widely used: 18650 batteries are widely used in consumer electronics, power tools, portable devices, and electric vehicle battery packs (such as Tesla Model S and early X models)
In fields such as battery packs, solar energy storage systems, high-intensity flashlights, medical equipment, wireless communication devices, etc.
Flexible combination method: 18650 batteries can be combined in series and parallel to form battery packs of different voltages and capacities to meet the needs of different devices.
Safety performance: Although 18650 batteries have high energy density and good performance, they also need to be equipped with safety protection measures, such as temperature monitoring, overcharge and over discharge protection, to prevent accidental incidents
Born. In summary, 18650 lithium batteries have been widely used and recognized worldwide for their mature manufacturing processes, stable performance, and wide applicability.
Comparison of 18650 26650 battery specifications
18650 and 26650 are standard specification numbers for cylindrical lithium-ion batteries, named after the size of the battery:
18650 battery specifications:
Diameter: 18 millimeters (18mm)
Height: 65 millimeters (65mm)
Capacity: Usually between 1100mAh and 3600mAh, but the most common products on the market are 1800mAh to 2600mAh.
Application: Widely used in various fields such as laptops, strong light flashlights, electric vehicles, mobile power banks, household appliances, etc.
26650 battery specifications:
Diameter: 26 millimeters (26mm)
Height: also 65 millimeters (65mm)
Capacity: Generally, the rated capacity is higher, such as between 3000mAh and 5000mAh, with a typical rated capacity of around 3000mAh.
Weight: Due to its larger size, the mass of a 26650 battery is generally greater than that of an 18650 battery. For example, the mass of an IFR26650 battery is approximately 94 grams.
Application: More suitable for application scenarios that require larger capacity and higher energy density, such as high-end flashlights, industrial equipment, power tools, energy storage devices, and certain specific models of electric vehicles
And large portable power banks, etc. The 26650 battery is commonly used on devices that require longer battery life and greater power output due to its larger size and capacity.
Standard specification for cylindrical lithium-ion batteries
The standard specifications of cylindrical lithium-ion batteries are determined by their diameter and height, usually identified by five digits, with the first two digits representing the diameter of the battery (in millimeters) and the last three digits
The number represents the height of the battery (also in millimeters).
Common cylindrical lithium-ion battery specifications include but are not limited to the following:
10440 battery: diameter 10mm, height 44mm.
14500 battery: diameter 14mm, height approximately 50mm.
14650 battery: diameter 14mm, height 65mm.
16340 battery (CR123A compatible size): diameter 16mm, height 34mm.
17490 battery: diameter 17mm, height 49mm.
18500 battery: diameter 18mm, height 50mm.
18650 battery: diameter 18mm, height 65mm, this is one of the most common and popular specifications on the market.
21700 battery: diameter 21mm, height 70mm, gradually popular in recent years due to higher energy density and better cost-effectiveness.
26500 battery: diameter 26mm, height approximately 50mm.
26650 battery: with a diameter of 26mm and a height of 65mm, it is used in some specific application scenarios due to its large capacity.
The cylindrical lithium-ion batteries with the above specifications are widely used in various fields such as consumer electronics, electric vehicles, power tools, energy storage systems, etc. Each specification of battery has a different capacity
Users can choose the appropriate battery specifications based on their actual application needs, taking into account the range and power output capability.
Tesla cylindrical lithium battery specifications
Tesla initially extensively used cylindrical lithium-ion batteries of 18650 specification in its electric vehicles, with a diameter of 18mm and a height of 65mm. Later, following
With the development of technology and the increasing demand for battery performance, Tesla has begun to shift towards larger specifications of batteries:
21700 battery:
With a diameter of 21mm and a height of 70mm, Tesla started using 21700 batteries in some production batches of Model 3. Compared to 18650 batteries, 21700 batteries have a larger volume and energy density
Higher.
4680 Battery:
With a diameter of 46mm and a height of 80mm, this is a high-capacity battery further developed by Tesla, aimed at significantly improving energy density and reducing costs. Tesla on Battery Day 2020
”At the event, 4680 batteries were announced, and plans were made to widely adopt this specification of battery in future products to improve vehicle range and reduce costs.
As Tesla's latest battery innovation, the 4680 battery adopts an advanced module free design, simplifies the battery structure, and improves production efficiency and battery performance. This new battery
Many improvements have been made at the battery cell level, including the use of dry electrode technology and anode free ear design, aimed at comprehensively improving the performance and production economy of electric vehicles.
