Some recent AA NiMH batteries

I trust Sanyo as they have always made the best. And who is Acupower,
who knows.
 >> Stay informed about: Some recent AA NiMH batteries 

ASAAR <caught DeleteThis @22.com> writes:
> I'd like to see some tests of unused fully charged cells showing
> remaining capacity with time. Two sets of times would be
> particularly interesting. One would be the number of days it takes
> for the self discharge of regular 2,500 or 2,700mah cells to
> decrease in capacity so that it would be equal to the remaining
> capacity in Eneloops after the same number of days.

This seems to be on the order of 3 months on average. One problem is
that non-Eneloops are very inconsistent. When my camera shows "low
battery", I put the cells on a BC900 (which displays the measured
voltage) and sometimes for one cell is at a much lower voltage than
the other, due to differing self-discharge rates even after just a few
weeks. As mentioned, I may be dealing with cells from a defective
batch of HR-3U's since other people have had similar experiences.

I just got my Eneloops so the jury is still out on whether their slow
self-discharge STAYS slow. My problematic HR-3U's seem to have had
their self-discharge speed up after a few charge cycles.

The main gadget I use nimh cells in where I care about capacity is an
audio recorder, and self-discharge doesn't matter so much for that. I
can charge up a bunch of cells and bring them to an event fresh off
the charger.
 >> Stay informed about: Some recent AA NiMH batteries 

On 08 Sep 2006 16:26:24 -0700, Paul Rubin
<http://phr.cx@NOSPAM.invalid> wrote:

> I think I'm going to migrate to Eneloops for most of my AA-powered
> devices. I picked up a few packs at the store and it's actually
> pretty cool that they're fully charged when you buy them.

I'd like to see some tests of unused fully charged cells showing
remaining capacity with time. Two sets of times would be
particularly interesting. One would be the number of days it takes
for the self discharge of regular 2,500 or 2,700mah cells to
decrease in capacity so that it would be equal to the remaining
capacity in Eneloops after the same number of days. The second
would be the number of days for self discharge to reduce the
capacities to 75% or 67% of maximum capacity. Sanyo may already
have charts showing this for Eneloops, but I'd also like to see it
for regular NiMH cells.
 >> Stay informed about: Some recent AA NiMH batteries 

>
> I think I'm going to migrate to Eneloops for most of my AA-powered
> devices. I picked up a few packs at the store and it's actually
> pretty cool that they're fully charged when you buy them.

I've been looking for the Eneloops for quite a while. Who has them for sale
?
thanks!
 >> Stay informed about: Some recent AA NiMH batteries 

"oceangoing" <w3cyykcv7q8gjpv.RemoveThis@jetable.org> writes:
> I've been looking for the Eneloops for quite a while. Who has them
> for sale ? thanks!

Wolf Camera and Ritz Camera (the two chains are now merged) have them
in my local stores. I paid $11.99 per 4-pack of AA's. You can also
order them online from ritzcamera.com. They only have AA size, no AAA
for now.

I've heard that Fry's Electronics has both AA's and AAA's, but AA's
are $12.99 a pack, but I haven't gone there to check.
 >> Stay informed about: Some recent AA NiMH batteries 

David Arnstein wrote:

>There is a respectable consensus that Sanyo makes great NiMH batteries,
>and there is a model with a claimed capacity of 2700 mAH on sale at
>Thomas Distributing.
>
>Thomas D. also offers a Maha PowerEx cell that claims 2700 mAH.
>
>Finally, Thomas D. sells an Accupower cell that claims 2900 mAH. Wow!
>
>I am always in the market for a cell that can hold a high voltage for
>a long time. I have a Sony flash gun that does NOT like low voltage.
>Cells that have slower self-discharge are also nice to have. Finally,
>I carefully avoid shoddy products because I fear damage to equipment
>from leaks or swelling.
>
>What do you think? Are any of these cells great or what?

Of the ones you mention, I have used only the Powerex 2700 AA
batteries mentioned above. Personally, I think they're pretty amazing.
Much longer lasting charge than the Powerex 2300 that they seem to
have replaced. They seem to hold charge for a long time on the shelf,
too (for NiMH batteries). I recommend them highly.

--
Mark Roberts Photography & Multimedia
www.robertstech.com
412-687-2835
 >> Stay informed about: Some recent AA NiMH batteries 

> Of the ones you mention, I have used only the Powerex 2700 AA
> batteries mentioned above. Personally, I think they're pretty amazing.
> Much longer lasting charge than the Powerex 2300 that they seem to
> have replaced. They seem to hold charge for a long time on the shelf,
> too (for NiMH batteries). I recommend them highly.

I haven't really stressed them yet, but I got some Powerex 27000 AAs from
Newegg recently along with a Powerex smart charger, and at a 240 mA charge,
they take over 10 hours to charge for me. Some old, well-used (and abused)
Panasonic 1600 mAh cells on the same charger are done in a measly 2 hours.


steve
 >> Stay informed about: Some recent AA NiMH batteries 

And copied widely too
make sure you get them from a reliable source.


"m Ransley" <ransley.TakeThisOut@webtv.net> wrote in message
news:4044-450204C1-196@storefull-3137.bay.webtv.net...
>I trust Sanyo as they have always made the best. And who is Acupower,
> who knows.
>
 >> Stay informed about: Some recent AA NiMH batteries 

"David Arnstein" <arnstein.RemoveThis@panix.com> wrote in message
news:edssuo$ckm$1@reader2.panix.com...
> There is a respectable consensus that Sanyo makes great NiMH batteries,
> and there is a model with a claimed capacity of 2700 mAH on sale at
> Thomas Distributing.
>
> Thomas D. also offers a Maha PowerEx cell that claims 2700 mAH.
>
> Finally, Thomas D. sells an Accupower cell that claims 2900 mAH. Wow!
>
> I am always in the market for a cell that can hold a high voltage for
> a long time. I have a Sony flash gun that does NOT like low voltage.
> Cells that have slower self-discharge are also nice to have. Finally,
> I carefully avoid shoddy products because I fear damage to equipment
> from leaks or swelling.
>
> What do you think? Are any of these cells great or what?


I think I use radio shack NiMH, have for years, I use them in an SB800 to
shoot weddings, swap them for a fresh set half way through and there's no
problem.

--
Regards,
Matt Clara
www.mattclara.com
 >> Stay informed about: Some recent AA NiMH batteries 

"David Arnstein" <arnstein.RemoveThis@panix.com> wrote in message
news:edssuo$ckm$1@reader2.panix.com...
> There is a respectable consensus that Sanyo makes great NiMH batteries,
> and there is a model with a claimed capacity of 2700 mAH on sale at
> Thomas Distributing.
>
> Thomas D. also offers a Maha PowerEx cell that claims 2700 mAH.
>
> Finally, Thomas D. sells an Accupower cell that claims 2900 mAH. Wow!
>
> I am always in the market for a cell that can hold a high voltage for
> a long time. I have a Sony flash gun that does NOT like low voltage.
> Cells that have slower self-discharge are also nice to have. Finally,
> I carefully avoid shoddy products because I fear damage to equipment
> from leaks or swelling.
>
> What do you think? Are any of these cells great or what?
> --
> David Arnstein
> arnstein+usenet@pobox.com

Hi.

Batteries are cheap and plentiful, so I just use Own Label Nimhs from
wherever. If and when I get a problem with one of my 4 or 5 sets, they will
get dumped.

I have more to worry about than a £1 battery.

Roy G
 >> Stay informed about: Some recent AA NiMH batteries 

High mAh and holding their charge for a long time don't always go
hand-in-hand. I noticed my Energizer 2500 mAh batteries, if they sat on
the shelf a week after being charged, would not power up my camera or my
GPS. My 2000 mAh Radio Shack batteries, on the other hand, are fine
after more than two weeks.

So, I tried the following experiment. I charged all my batteries to full
(well, to whatever my Energizer 15-minute charger considers full...I've
read some claims that this only actually brings them up to about 85%).
Then I set them all on the shelf, and measured their voltage a few times
over the next 350 hours. Here are the results.

There are my eight Energizer 2500 mAh batteries. First column is number
of hours on the shelf, and the other eight columns are the voltages.

0 1.396 1.393 1.391 1.378 1.406 1.316 1.398 1.382
16.78 1.284 1.285 1.284 1.27 1.282 1.287 1.299 1.274
22.40 1.275 1.276 1.275 1.261 1.28 1.286 1.293 1.27
38.63 1.262 1.263 1.261 1.25 1.268 1.275 1.278 1.258
50.98 1.258 1.259 1.256 1.242 1.264 1.272 1.272 1.253
117.38 1.188 1.194 1.175 0.964 1.22 1.251 1.237 1.108
181.67 1.006 0.96 0.945 0.929 1.042 1.223 1.185 0.937
289.70 0.95 0.936 0.926 0.916 0.935 0.974 0.963 0.921
351.12 0.946 0.935 0.925 0.916 0.93 0.949 0.958 0.92

Here are the voltages for my 4 Duracell 2050 mAh batteries:

1.356 1.363 1.265 1.267
1.334 1.337 1.26 1.261
1.332 1.335 1.259 1.261
1.325 1.325 1.257 1.259
1.32 1.32 1.256 1.258
1.305 1.303 1.25 1.252
1.295 1.292 1.245 1.248
1.282 1.278 1.243 1.245
1.276 1.272 1.242 1.245

At 350 hours, they are down to where the Energizers were after only
about 50 hours.

And here are the Radio Shacks:

1.396 1.379 1.397 1.249 1.372 1.377
1.376 1.364 1.377 1.231 1.357 1.362
1.374 1.362 1.374 1.23 1.355 1.36
1.364 1.354 1.363 1.225 1.353 1.352
1.358 1.349 1.357 1.223 1.343 1.348
1.335 1.328 1.332 1.201 1.321 1.329
1.323 1.317 1.318 1.182 1.307 1.316
1.306 1.301 1.3 1.143 1.287 1.299
1.299 1.294 1.292 1.116 1.278 1.292

Here are the Energizers again, this time in terms of percentage down the
voltage is compared to the initial voltage:

0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00%
8.02% 7.75% 7.69% 7.84% 8.82% 2.20% 7.08% 7.81%
8.67% 8.40% 8.34% 8.49% 8.96% 2.28% 7.51% 8.10%
9.60% 9.33% 9.35% 9.29% 9.82% 3.12% 8.58% 8.97%
9.89% 9.62% 9.71% 9.87% 10.10% 3.34% 9.01% 9.33%
14.90% 14.29% 15.53% 30.04% 13.23% 4.94% 11.52% 19.83%
27.94% 31.08% 32.06% 32.58% 25.89% 7.07% 15.24% 32.20%
31.95% 32.81% 33.43% 33.53% 33.50% 25.99% 31.12% 33.36%
32.23% 32.88% 33.50% 33.53% 33.85% 27.89% 31.47% 33.43%

and the Duracells:

0.00% 0.00% 0.00% 0.00%
1.62% 1.91% 0.40% 0.47%
1.77% 2.05% 0.47% 0.47%
2.29% 2.79% 0.63% 0.63%
2.65% 3.15% 0.71% 0.71%
3.76% 4.40% 1.19% 1.18%
4.50% 5.21% 1.58% 1.50%
5.46% 6.24% 1.74% 1.74%
5.90% 6.68% 1.82% 1.74%

and Radio Shack:

0.00% 0.00% 0.00% 0.00% 0.00% 0.00%
1.43% 1.09% 1.43% 1.44% 1.09% 1.09%
1.58% 1.23% 1.65% 1.52% 1.24% 1.23%
2.29% 1.81% 2.43% 1.92% 1.38% 1.82%
2.72% 2.18% 2.86% 2.08% 2.11% 2.11%
4.37% 3.70% 4.65% 3.84% 3.72% 3.49%
5.23% 4.50% 5.65% 5.36% 4.74% 4.43%
6.45% 5.66% 6.94% 8.49% 6.20% 5.66%
6.95% 6.16% 7.52% 10.65% 6.85% 6.17%

So, based on this, I'll go with the Energizers if I can charge them just
before use, and only need them to last that day. For batteries to
charge up and stick in my backpack to have on hand if I need them,
though, the last two Duracells seem to be the best choice, and then the
other Duracells and the Radio Shacks.

Since doing the above measurements, I bought two 2650 mAh Duracells, and
did a similar test with them. Here's the voltages:

0.00 1.393 1.392
2.37 1.376 1.374
8.58 1.361 1.359
54.60 1.312 1.309
137.35 1.28 1.278
180.22 1.274 1.272
319.13 1.264 1.259
482.52 1.244 1.217

and as percentages:
0% 0%
1.22% 1.29%
2.30% 2.37%
5.81% 5.96%
8.11% 8.19%
8.54% 8.62%
9.26% 9.55%
10.70% 12.57%

Quite a bit better than the Energizers, but not as good as the older
Duracells or the Radio Shacks.

--
--Tim Smith
 >> Stay informed about: Some recent AA NiMH batteries 

Tim Smith <reply_in_group DeleteThis @mouse-potato.com> writes:
> High mAh and holding their charge for a long time don't always go
> hand-in-hand. I noticed my Energizer 2500 mAh batteries, if they sat on
> the shelf a week after being charged, would not power up my camera or my
> GPS.

Sounds like they are defective and/or the 15 minute charger messed
them up somehow. They should not self-discharge THAT quickly. I have
a bunch of similar cells and the results are much more variable. I've
been using a LaCrosse BC900 charger, usually at 500 mA charging rate.
 >> Stay informed about: Some recent AA NiMH batteries 

"Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message
news:7x3bb0a64n.fsf@ruckus.brouhaha.com...
> Tim Smith <reply_in_group.TakeThisOut@mouse-potato.com> writes:
>> High mAh and holding their charge for a long time don't always go
>> hand-in-hand. I noticed my Energizer 2500 mAh batteries, if they sat on
>> the shelf a week after being charged, would not power up my camera or my
>> GPS.
>
> Sounds like they are defective and/or the 15 minute charger messed
> them up somehow. They should not self-discharge THAT quickly. I have
> a bunch of similar cells and the results are much more variable. I've
> been using a LaCrosse BC900 charger, usually at 500 mA charging rate.

That's what I think too. I think the 15 min charger is the problem not the batteries.
I have lots of Energizer NiMH batteries and they do not self discharge like that, but
then I don't use a 15 min charger.

Adam
 >> Stay informed about: Some recent AA NiMH batteries