Cylindrical Battery Naming Rules: What Do the Numbers Represent?
Cylindrical lithium battery model numbers typically consist of 5 digits (except for 4680, which omits the trailing 0):
First two digits: Indicate the battery diameter (in millimeters)
Middle two digits: Indicate the battery height (in millimeters)
Last digit: Usually "0", indicating that the battery is cylindrical.
For example:
18650 → Diameter 18mm, height 65mm, cylindrical
4680 → Diameter 46mm, height 80mm (the "0" indicating cylindrical shape is omitted)
Below, we will introduce the specifications, characteristics, and application scenarios of several mainstream cylindrical batteries one by one.
Detailed Explanation of Mainstream Cylindrical Lithium Battery Models
Dimensions: Diameter 18mm, Height 65mm
Features: The most technologically mature cylindrical battery type, with an energy density of approximately 170Wh/kg, extremely high stability, and excellent consistency.
Applications: Widely used in laptops, power tools, and power battery packs with a capacity of around 10kWh. It was a common type of battery in early electric vehicles (such as the Tesla Roadster).
Dimensions: Diameter 21mm, Height 70mm
Features: Compared to 18650, the volume is increased, with significantly improved single-cell capacity and energy density, and higher space utilization.
Applications: Digital products, electric vehicles (such as early versions of Tesla Model 3/Y), self-balancing scooters, power tools, etc., it is currently the mainstream high-performance cylindrical battery.
26650 Battery：
Dimensions: Diameter 26mm, Height 65mm
Features: Large capacity, good consistency, and a trend of gradually replacing 18650 capacitors.
Applications: Scenarios with high capacity requirements, such as some power tools and energy storage devices.
32650 Battery：
Dimensions: Diameter 32mm, Height 65mm
Features: Cell capacity typically ranges from 4500 to 6500mAh, supporting both lithium iron phosphate and ternary lithium chemistry systems.
Applications: Electric vehicles, residential/portable energy storage, industrial equipment, power tools. Major suppliers include ATL and LG.
4680 Battery：
Dimensions: Diameter 46mm, Height 80mm
Whether it's the classic stability of the 18650 or the performance breakthrough of the 4680, the core of the naming and classification of cylindrical lithium batteries has always been "size". Different cell models are essentially adapted to the capacity and volume requirements of different scenarios by adjusting the diameter and height. When choosing, you only need to check whether the size is suitable, and then combine it with energy density and application scenario to filter.
