18650 Battery Size and Voltage
18650 = 18.0 mm diameter x 65.0 mm height, 3.7 V Li-ion rechargeable, typically ~3500 mAh.
Open the interactive Standards & Sizes tool →Key facts
| Diameter x height | 18.0 x 65.0 mm |
|---|---|
| Voltage | 3.7 V nominal |
| Chemistry | Li-ion (NMC/NCA) |
| Capacity | ≈ 3500 mAh |
| Typical use | Laptops, power banks, power tools |
Frequently asked questions
What does 18650 mean?
'18' = 18 mm diameter, '65' = 65 mm length, '0' = cylindrical; it is a 3.7 V Li-ion cell.
Is 18650 the same size as AA?
No. 18650 (18 x 65 mm, 3.7 V) is larger than AA (14.5 x 50.5 mm, 1.5 V) and is rechargeable Li-ion.
Related pages
18650 Battery Size is part of Standards & Sizes on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.
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