First of a few unrelated questions about 2 subjects relating to batteries:
1. I keep seeing these AA to D cell adapters. I've seen ones that hold 1-AA in a D adapter, and one that holds 3-AA's in a D adapter. I read a post where someone claimed there is also a 2-AA to D adapter, but after a Google search I cant find them.
Batteryjunction has the 1-AA to D, and the 3-AA to D adapters, and they have the 3-AA to D adapters running in series(4.5v) or parallel(1.5v). The questions here are: If you compared 2 identical LED flashlights, say a Fenix TK-70, with one using 4- regular alkaline D cells and the 2nd TK70 using 4 of the 3-AA adapters with 3 AA alkalines in each(in parallel), which of the 2 lights would run longer on the various brightness settings before the batteries ran dead?
Also, if you were to compare the same 2 Fenix TK-70's, but instead of using alkalines in the 3-AA adapter and alkaline D's in the other TK-70, you used NiMh AA's in 3-AA adapters in one tk-70 and NiMh D's in the other Tk-70, which light would run longer on the various brightness settings before going dead using NiMh rechargeables ?
In both comparisons above^, the batteries would be the same brand, ie. Duracell AA's in 3-AA adapters vs Duracell D's in one light, and in the other Tk-70 comparison using NiMh batteries, since Sanyo doesnt make D eneloops for whatever reason, lets say you were comparing Tenergy Centura NiMh D's in one TK-70 and Centura NiMh AA's in 3-AA to D adapters in the other TK-70.
2. Next unrelated battery question: When looking for rechargeable RCR123's for the 1st time ever last year, I initially noticed that they were 3v just like their disposable Lithium counterparts, but then I heard about 16340, which are about the same size, but they have voltages of 3.7-4.2 range. But if you put a 16340 with that higher voltage in a gadget that is made specifically for only 3v, then you may likely destroy the gadget or fry it. Then to make things even more confusing and maybe more dangerous, I took a closer look at batteries labeled as RCR123's, but noticed that many of them are 3v, others are 3.6v still others are 3.7 - 4.2v! So it seems a bit irresponsible to label different batteries with completely different voltages with the same name! Wasnt the whole point of calling these higher voltage RCR123 sized batteries by the name "16340", so that it would be obvious that these were different batteries, so that there is no confusion that may(and will) cause people to buy the wrong batteries and fry their gadgets?
Why would companies label their 3.6 - 4.2v rechargeable batteries RCR123's instead of 16340's? Why not only label the 3v Li-Ion 123's RCR123, and name the 3.7 - 4.2v batteries 16340, and be consistent in that labeling? Wouldnt that be the safer, and more responsible thing to do? I mean, when I went to buy 3.7v 14500's, I didnt see them labeled as AA's!
3. Lastly, why doesnt Sanyo make C and D Eneloops?