The series of numbers used to describe the cell is actually directly defining the size of the cell...
10440 = 10mm x 44mm, The "0" on the end usually just means that it is "cylindrical."
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08400: Same dimensions as a AAAA cell.
Found in small form factor ecigs (the 9mm diameter jobs). Convenient size... Poor battery life (~150mAH). Plan on lots of charging options and owning multiples. Check with manufacture of ecig to make sure they are using safe chemistry cells before purchase.
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10440: same dimensions as a AAA cell.
Any 3.7V 10440 with a label rating higher than ~300mAH should be laughed at, pointed at, and made fun of. The purchasing of any such cells with ridiculous claims only encourages the continued practice of blatant lies in the industry. Do not support it.
Searching around the net for cells of this size may reveal many possible results in a 3.7V cell, the problem is that the only cells in this size that would be safe for use in an ecig would be LiMn (IMR) or LiFePO4 chemistry. Do not use Lithium Cobalt chemistry cells in this size to drive an ecig, the load is far beyond the maximum safe discharge rate for those cells.
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14500: same dimensions as a AA cell.
Any 3.7V 14500 with a label rating higher than ~750mAH should be laughed at, pointed at, and made fun of. The purchasing of any such cells with ridiculous claims only encourages the continued practice of blatant lies in the industry. Do not support it.
In this cell size, with most normal atty's the current draw is technically still on the high side for safety. I would suggest looking into LiMn (IMR) chemistry cells for this cell size for use in ecigs. The performance will be more consistent and the cycle life and safety will be much higher. AW sells very honestly rated IMR (red label) cells in this size. Check them out!
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16340: same dimensions as a CR123 cell.
Any 3.7V 16340 with a label rating higher than ~650mAH should be laughed at, pointed at, and made fun of. The purchasing of any such cells with ridiculous claims only encourages the continued practice of blatant lies in the industry. Do not support it. (Even AW has his cells over-rated here by too large a margin, I like most AW cells, but his black label protected RCR123s are mediocre in capacity and performance, most of the other cells he has sold over the years have been much better).
Basically this cell size is on that same barrier of safe operation as a 14500 for the regular LiCo chemistry stuff. LiMn (IMR) chemistry would result in much better performance. AW also sells an honestly rated IMR (red label) cell in this size!
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17500: Same length as a AA, roughly same diameter as a CR123. imagine a CR123 x 1.5X the length.
Good quality Lithium Cobalt protected in this size can safely handle even low resistance atomizers (down to ~1.8Ohm). AW brand 17500s have a label rating of 1100mAH and routinely test out HIGHER than that label rating at more normal discharge rates. IMR chemistry may be available from some sources but are not necessary at this cell size. I wish more battery mods took advantage of this size, it would be a great balance of size and capacity.
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18500: Same length as a AA, 18.5mm diameter (~2mm thicker than a CR123)
Typical capacity of LiCo in this size is around 1400-1500mAH. Plenty of oomf to run ecigs safely.
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17670: length and diameter roughly equal to 2xCR123 cells stacked in series.
Typical capacity of LiCo in this size is around 1500-1600mAH. Plenty of oomf to run ecigs safely.
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18650: Length of 2xCR123s end to end, 2mm thicker.
True capacity varies from 2000-3000mAH. Don't trust "3000mAH" claims from brands like ultra-stupid-fire and stuff. Higher capacity doesn't always mean better performance in an ecig application.
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Cell quality and charger quality is very important for both safety and over-all user satisfaction. A protection circuit is not likely to prevent the type of safety issue that can arise as a result of a poorly made charger or cell.
Check out the Pila IBC charger.
Eric