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Jeff Liebermann Jeff Liebermann is offline
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Default Video showing heavy flour in AA batteries: any way for layman to test NiMH batteries?

On Sat, 26 Oct 2013 13:31:34 -0700 (PDT), Amanda Riphnykhazova
wrote:

Is there any way of testing them to make sure they are what they say
they are before leaving misleading positive feedback?


Yes. I use a West Mountain Radio CBA-II analyzer:
http://www.westmountainradio.com/product_info.php?products_id=cba4
http://802.11junk.com/jeffl/NiMH/cba-II.jpg

An NiMH cell discharge graph will look something like this:
http://802.11junk.com/jeffl/NiMH/Duracelll-NiMH-2050.jpg
http://802.11junk.com/jeffl/NiMH/Energizer-NiMH-2300.jpg
The 2300 ma-hr cell was only good for 2000 ma-hr. However, there's a
catch. I ran the test with a rather fast high current 1C discharge at
2.0 and 2.3 amps respectively. You'll get results closer to the
advertised capacity if you use C/10 discharge rate. However, if you
really want to impress your friends and accomplises, run it at C/100
discharge rate, and you'll get some really impressive capacity
numbers.

I also have a Philips TSU500 remote in which I use slightly pricey
Sanyo Eneloop batteries supposedly heavily quality controlled by
Costco before sale. They are now possibly as old as 6-8 months
and used to last a week or so before stopping working. Now they
can go from fully charged (2-3 days in a charger) to dead in 3 days.
Again, I am wondering if there is any way to test them before
I decide that they need replacing rather than that the TSU500
itself is chewing up batteries and needs replacing!


Eneloop are good batteries. There are competative low self-discharge
batteries that are just as good if you want to save money. The catch
is that Eneloop batteries do not like to be fast charged. Sanyo sells
a slow charger that works just fine.
http://www.eneloop.info/eneloop-products/faqs/faqs-chargers.html
Though it is possible to charge an eneloop battery in a "Quick
Charger", it is not recommended. We recommend charging eneloop
batteries in a NiMh charger that is 2 hours or more. Charging
eneloop batteries in a "Quick Charger" can reduce the overall
life of the battery.
My guess(tm) is that you used a fast charger, and killed the cells.

Also, note that there are different types of Eneloop cells:
1500 times rechargeable eneloop battery (2nd generation) has a dark
gray cover around the positive electrode and a crown logo on the
side. HR-3UTGA (AA) / HR-4UTGA (AAA).
1000 times rechargeable eneloop battery (1st generation) has a white
cover around the positive electrode and there isn't a crown logo on
the side. HR-3UTG (AA) / HR-4UTG (AAA).

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Jeff Liebermann
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Skype: JeffLiebermann AE6KS 831-336-2558