On Mon, 29 May 2017 17:54:14 -0400, "(PeteCresswell)"
wrote:
Per :
use rechargeables.
I suspect that the issue for most people is dollars-and-cents battery
costs, but instead whether-or-not the light works when somebody grabs it
during a power failure or something after it's been on the shelf for 3
months.
There's another issue, which is what inspired me to get away from
alkaline and switch to LiIon and NiMH. Just about every alkaline
battery brand that I've tried will leak and rot out the device it is
suppose to power. I just recycled yet another 2D Maglite flashlight.
At least once per month, I have clean out the guts from a 2way radio,
clock, weather station, etc from the crud oozing out of alkaline
cells. There must be a better way.
For devices that require AA and AAA cells, I'm using LSD (low self
discharge) NiMH cells, mostly Eneloop. I had to use a pair of FRS
radios last weekend which were last charged in Dec 2016. 6 months
later, the charge indicator showed about 80% charge and they ran the
radios all day. Good enough.
https://en.wikipedia.org/wiki/Eneloop#AA_size
See charge retention table.
For flashlights, I've almost finished switching to all LiIon
batteries, mostly 18650 and 14500.
http://802.11junk.com/jeffl/crud/LiIon%20Flashlights.jpg
That's about 1/3 of my growing collection of cheap LiIon batteries and
flashlights. Why so many? Because most of what arrives is a mixture
of not what I ordered, mechanical defects, premature electrical
failure, bad design, or bad construction. To insure that things will
go awry, I'm also buying nothing but the cheapest LiIon batteries at
$0.85/ea for 14500 to $1.30 for 18650. Why buy bottom of the line?
Because it's my contention that bottom of the line batteries are a
better deal on the basis of cost per energy delivered than buying
quality high capacity cells. It will take another 6 months or so to
be sure, but so far so good. Cheap 18650 battery capacity at 1.5A,
which is at the high end of what a flashlight will draw:
http://802.11junk.com/jeffl/battery-tests/18650.jpg
Drivel: There's even a web site for cheap flashlight enthusiasts:
http://budgetlightforum.com
The only fly in the flashlight ointment is the cost of a decent
battery charger. Most of the really cheap battery chargers are badly
designed, dangerous, or both. For example, this loser sells for about
$0.50 with many flashlight and battery combinations:
http://lygte-info.dk/review/Review%20Charger%20Bowei%20HC-103W%20UK.html
How customs even lets them into the country is a mystery.
Before you buy a charger, check he
http://www.lygte-info.dk/info/indexBatteriesAndChargers%20UK.html
Also avoid any dual battery charger with only one LED light. These
charge 2 batteries in parallel, which is a rather bad idea, but will
work for one battery at a time.
Real LiIon chargers are quite a bit more expensive. These are good so
far:
http://www.ebay.com/itm/301383587686 $10
http://www.ebay.com/itm/331572608015 $17.20
Bottom line is that you can get a decent bottom of the line flashlight
system for:
flashlight: $3 to $8
18650 battery: $1.50
Charger $10
==========================
Total $15 (approx)
Of course, the expensive charger can be used with multiple
flashlights, so the 2nd flashlight will cost only about $5.
For LiIon battery packs with multiple cells, I use a balance charger:
https://hobbyking.com/en_us/catalogsearch/result/?q=imax+b6
The charger is the most important and most expensive part of the
system. I built a 10watt LED light, that runs on 11.3VDC, which uses
a balance charger.
Oh yes, self discharge. Li-Ion is as good or better than LSD NiMH:
http://batteryuniversity.com/learn/article/elevating_self_discharge
See Tables 3 and 5. There's a rumor that storing a LiIon battery at
full charge would shorten its useful life. That was certainly a
problem with laptop batteries during the 1990's, but seems to have
been eliminated in the current offerings.
Anyway, think rechargeable, recycle your alkalines, and return the
flashlights to Costco.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558