AA cell measures 49.2–50.5 mm (1.94–1.99 in) in length, including the button terminal—and 13.5–14.5 mm (0.53–0.57 in) in diameter.
The 18650 part number provides it nominal dimensions. The first two digits of the part number indicate the cell is 18 mm in diameter. The last three digits provide the length of 65 mm.
On April 20, 2021 at 7:52 PM, "Tom via groups.io" <tjgerard@...> wrote:
Aren’t the batteries your talking about a good bit larger than AA?
Tom
