On Sat, 03 Nov 2018 15:35:08 -0000, "Steven Watkins"
wrote:

On Sat, 03 Nov 2018 02:33:37 -0000, Rod Speed wrote:



"Steven Watkins" wrote in message
news
On Fri, 02 Nov 2018 23:22:18 -0000, Rod Speed
wrote:

Steven Watkins wrote

Why was the AA LiIon size ever invented if it's no good?

Because its one of the most common battery sizes.

But due to it's differing voltage, it was never intended as a direct
replacement, but to power new devices that wanted more voltage, such as
LED torches.

But some arent idea with 18650. There are in fact one
hell of a range of LiIon cells of various sizes and if it
wasn't for the problem that LiIon doesn't work well
in the smaller diameter cells, it does make sense to
use an existing very common cell size.

But that problem is significant. And a single 18650 fits very well into a pocket torch or anything else I can think of except a mobile phone.
3.7 volt AA batteries would be a nightmare. There arer "standards"
for a reason.

Just like the insane "direct wire" LED tubes that fit the same
tombstones as the "direct fit" and flourescent tubes that need the
ballast. - but are rewired directly to line voltage.