[ale] [OT] any experience with low self discharge NIMH batteries

[Alex Carver]

On 3/8/2013 19:25, Ron Frazier (ALE) wrote:
>
>
> Alex Carver <agcarver+ale at acarver.net> wrote:
>
>> On 3/4/2013 21:04, Ron Frazier (ALE) wrote:
>>> Hi all,
>>>
>>> A few months back, we had a thread here about new advanced LED
>>> flashlights.  I bought one that has the giant 1/4 in LED inside, and
>> is
>>> bright enough to be competitive with an incandescent krypton bulb.
>> Love
>>> the flashlight.  Works great.  However, it's powered by only 2 AA
>>> batteries and they're dying 6 months later.  I'm considering using
>> NIMH
>>> rechargeables there.  The problem with that is that, left on the
>> shelf,
>>> standard NIMH batteries lose 10 % - 30 % of their charge per month.
>> So,
>>> you could pick up the flashlight and not have it working when you
>> need it.
>>>
>>> Enter Low Self Discharge NIMH batteries.  These are relatively new.
>> They
>>> claim to lose only about 15 % of their charge after a year.  So, you
>>> could get away with charging the flashlight batteries only every 6
>>> months or so.
>>>
>>> Two main brands of LSD NIMH seem to dominate.  Eneloop by Sanyo and
>>> Imedion by Powerex (Maha Energy).  I've used some standard Powerex
>> NIMH
>>> 2700 mah batteries and I like them, but I have to charge them if
>> they've
>>> been sitting a while.
>>>
>>> Does anyone have any experience with the LSD NIMH batteries.  Is it a
>>> good idea to use them in a flashlight, or stick with Duracells at $ 3
>> /
>>> pair, or other alkalines?  I know Fry's and Home Depot / Lowes
>> sometimes
>>> sell batteries in packages at lower unit cost.  I haven't done a
>> price
>>> analysis on those.
>>
>> For something like a flashlight that can handle deep discharge try one
>> of the lithium iron (that's Fe not a typo of 'ion') formulations.  You
>> can pick up AA versions at the hardware store next to the solar powered
>>
>> garden lights.
>
> Hi Alex,
>
> Thanks for that info.  I did some research on these and they sound interesting.  The attributes of that battery chemistry sound cool and it's probably worth keeping an eye on.  I don't think it will work in my case since these batteries are 3.2 V and my flashlight expects to see 3X 1.5 V cells.  I may end up going with some of the LSD NIMH ones.
>
> Sincerely,

Ah, but you're missing half the fun of tinkering with the flashlight to 
use them. :)  A tiny, three terminal 4.5V regulator wedged inside and 
you'd be set.