One of the most popular and commonly found cells in the battery pack or power supply are 18650 battery cells, here we have listed all the possible technical 18650 battery specifications that can be very useful in implementing any technical design of your product or gadgets.
What is an 18650 battery? and specifications.
The 18650 battery is a Li-ion battery named after its 18mm × 65mm cylindrical size (diameter × height). When compared to AA size, it’s height and diameter both are larger. They are not replacements for AA or AAA size cells.
The 18650 battery has a nominal voltage of 3.6v and has capacity between 1200mAh and 3600mAh (read as mili-Amp-hours).
The battery type 18650 are popular in rechargeable and high current draining devices considering its high-level capabilities like 250+ charge cycle and higher energy density. The 18650 Li-ion battery due to its adaptability all around can be found in various fields, say, electric cars/ scooters, power banks, utility gadgets such as emergency lamps, torchlight, etc.
Its safety property along with its high output current and energy capacity makes this battery popular among tech industries.
The 18650 battery specification includes its properties like the voltage, capacity, charge-discharge cycle, output current, output voltage and so on. This is a generalized specification of 18650 Li-ion battery, only properties marked with the remark of “Standard” are common to all 18650 batteries else not.
This is to note that other properties such as capacity charge discharge cycles and capacity (mAh) are subjected to independent technologies to increase capability values to the consumers by doing research and development. All the 18650 specs are listed in table with detail. You might like this article on simple 18650 battery charger circuit with auto cutoff.
18650 battery specification table:
|18 ✖ 65 mm
|Standard (dd ✖ hh)
|2 - 2.5 volts
|Check respective datasheet
|30gms to 55gms
|Depends on capacity & technology
(Energy per cell)
|1.5 - 11.5Wh
|Charge discharge cycle
|250 to 2000
|In number ()
|Optimum /Minimum charging time
|2.5 hrs to 3.5 hrs
|CC and CV
|4.2v - 5v
|5 volt max
|Check C rating*
|Check C rating*
|Regular and Flat top
|6 - 10 %
Specs mention in above table is general, always check datasheet for accurate results.
Click for (Compressive comparison 18650 vs 21700 battery)
18650 battery size / dimension:
The Standard 18650 battery size is 18 ✖ 65mm.
The 18650 battery length is 65mm. The diameter of the 18650 battery is 18mm.
To be more precise, it has an approximate length of 65mm and an approximate diameter is 18mm but technically 18650 battery size is allowed with some tolerance in length and diameter. Thus you could find specification written as, (say) 18 ± 0.41mm ✖ 65 ± 0.25mm on datasheet and features of Li-ion cell.
Just remember 18 ✖ 65mm as a standard size, remaining things will be taken care of by designers and manufacturers of devices and batteries.
The size of the 18650 battery is allowed for the reason that, various gadgets or devices inhibit different locally developed technologies. That might not able to manufacture exact precise length & diameter of either batteries or battery holding space, to fit the device or 18650 Lithium battery respectively.
18650 battery data sheet:
The data sheet specification describes the technical parameters and standard tested output of each for the particular component or module.
Here we have discussed 18650 battery data sheet, on paper its a li-ion rechargeable cell supplied by various electronics manufacturing companies.
There are hundreds of 18650 battery data sheets available belonging to different model of 18650 batteries, there are lots of different models available varying in current rating and charge holding capacity. Also top manufacturing companies have their cell model with inbuilt overcharge protection and short circuit protection circuit to prevent damage to the cell as well as device in which it is used.
List of top 18650 battery manufacturing companies along with the data sheets of popular 18650 battery:
Battery Model: Samsung 25R5 18650
Datasheet link: Samsung battery datasheet
Battery Model: Sony VTC6 18650 battery (US18650VTC6)
Datasheet link: Sony vtc6 datasheet
Battery Model: Sony VTC5 18650 Battery (US18650VTC5)
Datasheet link: Sony vtc5 datasheet
Battery Model : LG HG2 18650 Battery
Datasheet link: LG HG2 datasheet
Battery Model: Panasonic A 18650 Battery (NCR18650A)
Datasheet link: Panasonic A18650 datasheet
From their data sheet you can analyze and study what parameters are to be considered. All these parameter to be keep in mind before, while and after manufacturing, testing and launching the a final product in the market.
We have discussed these all 18650 circuits and how to use them here.