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Do NiMH batteries expire?

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April 17, 2005 4:21:29 AM

Archived from groups: rec.photo.digital (More info?)

Nowadays alkaline batteries all seem to come with an expiration date stamped
on them. Do NiMH batteries expire like alkaline batteries? I've heard that
NiMH batteries can be recharged up to 500-1000 times, but what if you only
recharge them a few times a year, how long would they last?

More about : nimh batteries expire

Anonymous
April 17, 2005 4:21:30 AM

Archived from groups: rec.photo.digital (More info?)

<curious@nospam.com> wrote in message
news:9no361l77vvd26ejlh43lhd29irjn2rurj@4ax.com...
> Nowadays alkaline batteries all seem to come with an expiration date
> stamped
> on them. Do NiMH batteries expire like alkaline batteries? I've heard
> that
> NiMH batteries can be recharged up to 500-1000 times, but what if you only
> recharge them a few times a year, how long would they last?

You're actually better off keeping them fully charged.
My sets stay in their at all times (when not in use). *I've been using one
particular set for nearly 5 years now (since late 2000), and they still work
fine--though they can't keep up with the newer, high-capacity units I've
bought since (2300mAh vs much less).

I would higly recommend Maha chargers from Thomas Distributing (along with
their excellent PowerEx batteries).
Anonymous
April 17, 2005 4:21:30 AM

Archived from groups: rec.photo.digital (More info?)

In article <9no361l77vvd26ejlh43lhd29irjn2rurj@4ax.com>,
curious@nospam.com wrote:

> Nowadays alkaline batteries all seem to come with an expiration date stamped
> on them. Do NiMH batteries expire like alkaline batteries? I've heard that
> NiMH batteries can be recharged up to 500-1000 times, but what if you only
> recharge them a few times a year, how long would they last?

Despite what somebody else said in many posts, it is OK to let them run
down. They're only damaged if the charges are unbalanced and the weaker
cells become reverse charged by the stronger cells.

NiMH won't charge well after long periods of disuse. Most chargers
won't know when they're charged until they've become hot enough to
trigger the charger's thermal cut-off. If you're using a fast charger,
pull the cells out when they become hot (warm is OK). If you're using a
slow charger, check them every few hours and remove them when they're
warm. It's possibly that you can't get a good charge into the cells on
their first use. Use them and charge them again. They'll recover.


http://www.energizer.com/products/rechargeables/faqs.as...
Related resources
Can't find your answer ? Ask !
Anonymous
April 17, 2005 4:21:31 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> wrote in message
news:p Gl8e.320$Zi.41@fed1read04...
>
> <curious@nospam.com> wrote in message
> news:9no361l77vvd26ejlh43lhd29irjn2rurj@4ax.com...
>> Nowadays alkaline batteries all seem to come with an expiration date
>> stamped
>> on them. Do NiMH batteries expire like alkaline batteries? I've heard
>> that
>> NiMH batteries can be recharged up to 500-1000 times, but what if you
>> only
>> recharge them a few times a year, how long would they last?
>
> You're actually better off keeping them fully charged.
> My sets stay in their at all times (when not in use). *I've been using
> one particular set for nearly 5 years now (since late 2000), and they
> still work fine--though they can't keep up with the newer, high-capacity
> units I've bought since (2300mAh vs much less).
>
> I would higly recommend Maha chargers from Thomas Distributing (along with
> their excellent PowerEx batteries).

Oh...

More to the point...
Don't let your batteries become completely depleted.
This will basically destroy them, or at best lead to their early demise.
Anonymous
April 17, 2005 4:21:31 AM

Archived from groups: rec.photo.digital (More info?)

"Kevin McMurtrie" <mcmurtri@dslextreme.com> wrote in message
news:mcmurtri-9ECD30.21591716042005@corp-radius.supernews.com...
> In article <9no361l77vvd26ejlh43lhd29irjn2rurj@4ax.com>,
> curious@nospam.com wrote:
>
>> Nowadays alkaline batteries all seem to come with an expiration date
>> stamped
>> on them. Do NiMH batteries expire like alkaline batteries? I've heard
>> that
>> NiMH batteries can be recharged up to 500-1000 times, but what if you
>> only
>> recharge them a few times a year, how long would they last?
>
> Despite what somebody else said in many posts, it is OK to let them run
> down. They're only damaged if the charges are unbalanced and the weaker
> cells become reverse charged by the stronger cells.

Nobody (namely me) said anything against letting them "run down," but
prolonged "run down" storage can indeed deplete the batteries' ability to
hold a charge. I "run my batteries down" all the time...but I don't leave
them in that state for long. I DO leave them in my flash until they perform
poorly...then I charge them. I certainly wasn't trying to convey that one
should ALWAYS charge them after ANY use. No.

There are many differing advisements given from many different sources, but
the consensus I've found (which also matches my personal experience)
supports the assertion that one should store charged batteries...and
definitely avoid storing depleted batteries.

Batteries stored long term should be periodically charged (after several
months).

While the Energizer link you posted mentions that batteries can recover
after storage, note that they say the dreaded "UP TO five years storage."
The key there is "up to." As we know from every clothing store's sale ads
that flash great big numbers like **70% OFF**...it's only when you notice
those tiny, wildly powerful words "up to" which precede the big 70% that you
realise you're likely to find FAR less savings.

:) 

>
> NiMH won't charge well after long periods of disuse. Most chargers
> won't know when they're charged until they've become hot enough to
> trigger the charger's thermal cut-off. If you're using a fast charger,
> pull the cells out when they become hot (warm is OK). If you're using a
> slow charger, check them every few hours and remove them when they're
> warm. It's possibly that you can't get a good charge into the cells on
> their first use. Use them and charge them again. They'll recover.
>
>
> http://www.energizer.com/products/rechargeables/faqs.as...
Anonymous
April 17, 2005 4:21:32 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> wrote in message
news:FHl8e.321$Zi.237@fed1read04...
>
> "Mark²" <mjmorgan(lowest even number here)@cox..net> wrote in message
> news:p Gl8e.320$Zi.41@fed1read04...
>>
>> <curious@nospam.com> wrote in message
>> news:9no361l77vvd26ejlh43lhd29irjn2rurj@4ax.com...
>>> Nowadays alkaline batteries all seem to come with an expiration date
>>> stamped
>>> on them. Do NiMH batteries expire like alkaline batteries? I've heard
>>> that
>>> NiMH batteries can be recharged up to 500-1000 times, but what if you
>>> only
>>> recharge them a few times a year, how long would they last?
>>
>> You're actually better off keeping them fully charged.
>> My sets stay in their at all times (when not in use). *I've been using
>> one particular set for nearly 5 years now (since late 2000), and they
>> still work fine--though they can't keep up with the newer, high-capacity
>> units I've bought since (2300mAh vs much less).
>>
>> I would higly recommend Maha chargers from Thomas Distributing (along
>> with their excellent PowerEx batteries).
>
> Oh...
>
> More to the point...
> Don't let your batteries become completely depleted.
> This will basically destroy them, or at best lead to their early demise.

Sorry... But there's more:
Don't leave your batteries sitting without charging them for long periods.
NiMh batteries lose charge over time, and will eventually become completely
depleated even without use.
This is why it's good to have several "smart" chargers to leave them in
when not in use.
Anonymous
April 17, 2005 4:21:32 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> > You're actually better off keeping them fully charged.
> > My sets stay in their at all times (when not in use). *I've been using
> > one particular set for nearly 5 years now (since late 2000), and they
> > still work fine--though they can't keep up with the newer, high-capacity
> > units I've bought since (2300mAh vs much less).
> >
> > I would higly recommend Maha chargers from Thomas Distributing (along with
> > their excellent PowerEx batteries).
>
> More to the point...
> Don't let your batteries become completely depleted.
> This will basically destroy them, or at best lead to their early demise.

If you do leave the depleted for a long time, putting them through
several charge/discharge cycles will generally refresh them, though
maybe they're not as good as new afterwards.

Maha stuff is not really that great. My favorite fancy AA charger
these days is the LaCrosse BC-900, also available from Thomas
Distributing. It has separate LCD displays for each cell so it
actually shows you the realtime charging voltage, and the measured
capacity of each cell. It has a discharge/refresh function that
repeatedly discharges and recharges the cell until the capacity stops
increasing. You can set the charge current up to 1000 mA (about a 3
hour charge for 2500 mAH cells) for 3-4 cells or up to 1800 mA for 1-2
cells. And it comes with some decent (not fantastic) AA and AAA cells
(4 of each) and AA to C and D adapters. I might even buy a second one
sometime.
Anonymous
April 17, 2005 4:21:33 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xfyxq0zcn.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> > You're actually better off keeping them fully charged.
>> > My sets stay in their at all times (when not in use). *I've been using
>> > one particular set for nearly 5 years now (since late 2000), and they
>> > still work fine--though they can't keep up with the newer,
>> > high-capacity
>> > units I've bought since (2300mAh vs much less).
>> >
>> > I would higly recommend Maha chargers from Thomas Distributing (along
>> > with
>> > their excellent PowerEx batteries).
>>
>> More to the point...
>> Don't let your batteries become completely depleted.
>> This will basically destroy them, or at best lead to their early demise.
>
> If you do leave the depleted for a long time, putting them through
> several charge/discharge cycles will generally refresh them, though
> maybe they're not as good as new afterwards.
>
> Maha stuff is not really that great.

Thus sayeth you...
Maha chargers have kept old and new batteries going strong for five years
without fail.
You are in a minority on this one, as Maha chargers are roundly praised as
excellent.
-By far the most recommended charger in terms of word-of-mouth over the last
several years.

>My favorite fancy AA charger
> these days is the LaCrosse BC-900, also available from Thomas
> Distributing. It has separate LCD displays for each cell so it
> actually shows you the realtime charging voltage, and the measured
> capacity of each cell. It has a discharge/refresh function that
> repeatedly discharges and recharges the cell until the capacity stops
> increasing. You can set the charge current up to 1000 mA (about a 3
> hour charge for 2500 mAH cells) for 3-4 cells or up to 1800 mA for 1-2
> cells. And it comes with some decent (not fantastic) AA and AAA cells
> (4 of each) and AA to C and D adapters. I might even buy a second one
> sometime.

I think most folks don't prefer to carry on about such minutia.
All that is great if you really feel it necessary to do all that fiddling.
For me (and I think for most others), that is much ado about little...
:) 
Anonymous
April 17, 2005 4:21:34 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> Thus sayeth you... Maha chargers have kept old and new batteries
> going strong for five years without fail. You are in a minority on
> this one, as Maha chargers are roundly praised as excellent. -By
> far the most recommended charger in terms of word-of-mouth over the
> last several years.

Try hanging out on some RC forums, which are populated by battery nerds
like this place is populated by photo nerds. The Maha was last year's
charger. That was then, this is now.
Anonymous
April 17, 2005 4:21:35 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xbr8dgb92.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> Thus sayeth you... Maha chargers have kept old and new batteries
>> going strong for five years without fail. You are in a minority on
>> this one, as Maha chargers are roundly praised as excellent. -By
>> far the most recommended charger in terms of word-of-mouth over the
>> last several years.
>
> Try hanging out on some RC forums, which are populated by battery nerds
> like this place is populated by photo nerds. The Maha was last year's
> charger. That was then, this is now.

RC racers have unique needs related to competetive motor speeds/output that
are rarely of similar significant to photographers.
Anonymous
April 17, 2005 4:21:36 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> wrote in message
news:2Ln8e.338$Zi.223@fed1read04...
>
> "Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
> news:7xbr8dgb92.fsf@ruckus.brouhaha.com...
>> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>>> Thus sayeth you... Maha chargers have kept old and new batteries
>>> going strong for five years without fail. You are in a minority on
>>> this one, as Maha chargers are roundly praised as excellent. -By
>>> far the most recommended charger in terms of word-of-mouth over the
>>> last several years.
>>
>> Try hanging out on some RC forums, which are populated by battery nerds
>> like this place is populated by photo nerds. The Maha was last year's
>> charger. That was then, this is now.
>
> RC racers have unique needs related to competetive motor speeds/output
> that are rarely of similar significant to photographers.

sp: significance
Anonymous
April 17, 2005 4:21:37 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> > RC racers have unique needs related to competetive motor speeds/output
> > that are rarely of similar significant to photographers.
>
> sp: significance

If you like Maha cells so much, why don't you run some objective tests
on them and post the results. You might not be so enthusiastic
afterwards.
Anonymous
April 17, 2005 4:21:38 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xpswtnasd.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> > RC racers have unique needs related to competetive motor speeds/output
>> > that are rarely of similar significant to photographers.
>>
>> sp: significance
>
> If you like Maha cells so much, why don't you run some objective tests
> on them and post the results. You might not be so enthusiastic
> afterwards.

I was refering to Maha chargers.
Anonymous
April 17, 2005 4:21:39 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> > If you like Maha cells so much, why don't you run some objective tests
> > on them and post the results. You might not be so enthusiastic
> > afterwards.
>
> I was refering to Maha chargers.

Test results I've seen on the C-401FS indicate that it works pretty
well at the slow charge rate, but in fast charge mode it charges
inconsistently and gets the cells awfully hot. I don't see much point
to getting an expensive so-called smart charger if you can only use it
for slow charging.

For fast charging I really like the new Energizer 15 minute charger.
It uses forced air cooling so the cells get only slightly warm. It
comes with a wall wart switcher (16V 4A) and supposedly can run on 12
volt power, so you can run it in a vehicle directly from a cig plug.
And it's half the price of the Ray-o-vac setup that needs special
proprietary cells.

For less ultra-rapid charging, the BC-900 is my favorite. It's far
more flexible than the Maha and the discharge/analysis function is
great. I'm planning to use it to grade all of my batteries and weed
out the not-so-good ones.
Anonymous
April 17, 2005 4:28:49 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xhdi5na8s.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> > If you like Maha cells so much, why don't you run some objective tests
>> > on them and post the results. You might not be so enthusiastic
>> > afterwards.
>>
>> I was refering to Maha chargers.
>
> Test results I've seen on the C-401FS indicate that it works pretty
> well at the slow charge rate, but in fast charge mode it charges
> inconsistently and gets the cells awfully hot. I don't see much point
> to getting an expensive so-called smart charger if you can only use it
> for slow charging.

The term "smart charger" is generally used to differentiate between chargers
are able to "intelligently" sense the state of charge in the battery placed
in it...as opposed to those chargers which blindly apply a timed charge to
whatever battery is placed in them--having no awareness of what charge the
particular battery requires.

I don't have three Maha C-401FS...I have three C-204F chargers. Quick
charge mode isn't an issue because they don't have one. But because I have
three chargers each holding a set at all times, I am never in need of
straining batteries via repeated quick charges.

I wouldn't prefer to ever quick-charge any of my batteries, choosing instead
to keep three full sets charging--which means there is always a charged set
available.

>
> For fast charging I really like the new Energizer 15 minute charger.
> It uses forced air cooling so the cells get only slightly warm. It
> comes with a wall wart switcher (16V 4A) and supposedly can run on 12
> volt power, so you can run it in a vehicle directly from a cig plug.
> And it's half the price of the Ray-o-vac setup that needs special
> proprietary cells.
>
> For less ultra-rapid charging, the BC-900 is my favorite. It's far
> more flexible than the Maha and the discharge/analysis function is
> great. I'm planning to use it to grade all of my batteries and weed
> out the not-so-good ones.
Anonymous
April 17, 2005 5:02:27 AM

Archived from groups: rec.photo.digital (More info?)

curious@nospam.com wrote:
> Nowadays alkaline batteries all seem to come with an expiration date stamped
> on them. Do NiMH batteries expire like alkaline batteries? I've heard that
> NiMH batteries can be recharged up to 500-1000 times, but what if you only
> recharge them a few times a year, how long would they last?
>

While I am sure that after some period of years the chemicals in a NIMH
battery would deteriorate, many users here have reported several years
of useful life for the batteries. Since NIMH batteries tend to lose
their charge, just sitting, recharging them every three months or so is
a good practice. Since their cost is low, the issue is of minimal
concern. I would say, in average use, 3 to 5 years. I have some that I
have been using for almost 3 years.


--
Ron Hunter rphunter@charter.net
April 17, 2005 5:11:39 AM

Archived from groups: rec.photo.digital (More info?)

On Sat, 16 Apr 2005 21:38:12 -0700, "Mark²" <mjmorgan(lowest even number
here)@cox..net> wrote:

>> More to the point...
>> Don't let your batteries become completely depleted.
>> This will basically destroy them, or at best lead to their early demise.
>
>Sorry... But there's more:
>Don't leave your batteries sitting without charging them for long periods.
>NiMh batteries lose charge over time, and will eventually become completely
>depleated even without use.
>This is why it's good to have several "smart" chargers to leave them in
>when not in use.

Really? I read something once that said if the power goes out while you have
batteries in a charger, it will cause problems when the power comes back.
That's why I only leave my batteries in the charger if I anticipate using my
camera in the near future. If I don't anticipate needing to use my camera in
the near future, then I take the batteries out.

I just did a google search, and found someone mentioning that problem:

http://groups-beta.google.com/group/rec.photo.digital/m...

I wouldn't want to have batteries explode, and possibly cause a fire, if I
left them in the charger and the power went out.
Anonymous
April 17, 2005 5:11:40 AM

Archived from groups: rec.photo.digital (More info?)

curious@nospam.com wrote:
> On Sat, 16 Apr 2005 21:38:12 -0700, "Mark²" <mjmorgan(lowest even number
> here)@cox..net> wrote:
>
>
>>>More to the point...
>>>Don't let your batteries become completely depleted.
>>>This will basically destroy them, or at best lead to their early demise.
>>
>>Sorry... But there's more:
>>Don't leave your batteries sitting without charging them for long periods.
>>NiMh batteries lose charge over time, and will eventually become completely
>>depleated even without use.
>>This is why it's good to have several "smart" chargers to leave them in
>>when not in use.
>
>
> Really? I read something once that said if the power goes out while you have
> batteries in a charger, it will cause problems when the power comes back.
> That's why I only leave my batteries in the charger if I anticipate using my
> camera in the near future. If I don't anticipate needing to use my camera in
> the near future, then I take the batteries out.
>
> I just did a google search, and found someone mentioning that problem:
>
> http://groups-beta.google.com/group/rec.photo.digital/m...
>
> I wouldn't want to have batteries explode, and possibly cause a fire, if I
> left them in the charger and the power went out.
>
This is not a significant risk if you buy a smart charger, such as the
Maha 401. It will charge each battery separately, and will NOT
overcharge even if the power should go off during the charging. There
is, of course, always a certain risk with using any electrical device.


--
Ron Hunter rphunter@charter.net
Anonymous
April 17, 2005 5:26:43 AM

Archived from groups: rec.photo.digital (More info?)

In article <LIn8e.337$Zi.14@fed1read04>,
"Mark²" <mjmorgan(lowest even number here)@cox..net> wrote:

> "Kevin McMurtrie" <mcmurtri@dslextreme.com> wrote in message
> news:mcmurtri-9ECD30.21591716042005@corp-radius.supernews.com...
> > In article <9no361l77vvd26ejlh43lhd29irjn2rurj@4ax.com>,
> > curious@nospam.com wrote:
> >
> >> Nowadays alkaline batteries all seem to come with an expiration date
> >> stamped
> >> on them. Do NiMH batteries expire like alkaline batteries? I've heard
> >> that
> >> NiMH batteries can be recharged up to 500-1000 times, but what if you
> >> only
> >> recharge them a few times a year, how long would they last?
> >
> > Despite what somebody else said in many posts, it is OK to let them run
> > down. They're only damaged if the charges are unbalanced and the weaker
> > cells become reverse charged by the stronger cells.
>
> Nobody (namely me) said anything against letting them "run down," but
> prolonged "run down" storage can indeed deplete the batteries' ability to
> hold a charge. I "run my batteries down" all the time...but I don't leave
> them in that state for long. I DO leave them in my flash until they perform
> poorly...then I charge them. I certainly wasn't trying to convey that one
> should ALWAYS charge them after ANY use. No.
>
> There are many differing advisements given from many different sources, but
> the consensus I've found (which also matches my personal experience)
> supports the assertion that one should store charged batteries...and
> definitely avoid storing depleted batteries.
>
> Batteries stored long term should be periodically charged (after several
> months).


Only lead-acid batteries need to be stored fully charged. LiIon and
NiCd are actually damaged by periodic charging during storage. NiMH
doesn't care about storage, so why bother?



> While the Energizer link you posted mentions that batteries can recover
> after storage, note that they say the dreaded "UP TO five years storage."
> The key there is "up to." As we know from every clothing store's sale ads
> that flash great big numbers like **70% OFF**...it's only when you notice
> those tiny, wildly powerful words "up to" which precede the big 70% that you
> realise you're likely to find FAR less savings.
>
> :) 
>
> >
> > NiMH won't charge well after long periods of disuse. Most chargers
> > won't know when they're charged until they've become hot enough to
> > trigger the charger's thermal cut-off. If you're using a fast charger,
> > pull the cells out when they become hot (warm is OK). If you're using a
> > slow charger, check them every few hours and remove them when they're
> > warm. It's possibly that you can't get a good charge into the cells on
> > their first use. Use them and charge them again. They'll recover.
> >
> >
> > http://www.energizer.com/products/rechargeables/faqs.as...
Anonymous
April 17, 2005 5:47:16 AM

Archived from groups: rec.photo.digital (More info?)

In article <7xfyxq0zcn.fsf@ruckus.brouhaha.com>,
Paul Rubin <http://phr.cx@NOSPAM.invalid&gt; wrote:

> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> > > You're actually better off keeping them fully charged.
> > > My sets stay in their at all times (when not in use). *I've been using
> > > one particular set for nearly 5 years now (since late 2000), and they
> > > still work fine--though they can't keep up with the newer, high-capacity
> > > units I've bought since (2300mAh vs much less).
> > >
> > > I would higly recommend Maha chargers from Thomas Distributing (along
> > > with
> > > their excellent PowerEx batteries).
> >
> > More to the point...
> > Don't let your batteries become completely depleted.
> > This will basically destroy them, or at best lead to their early demise.
>
> If you do leave the depleted for a long time, putting them through
> several charge/discharge cycles will generally refresh them, though
> maybe they're not as good as new afterwards.
>
> Maha stuff is not really that great. My favorite fancy AA charger
> these days is the LaCrosse BC-900, also available from Thomas
> Distributing. It has separate LCD displays for each cell so it
> actually shows you the realtime charging voltage, and the measured
> capacity of each cell. It has a discharge/refresh function that
> repeatedly discharges and recharges the cell until the capacity stops
> increasing. You can set the charge current up to 1000 mA (about a 3
> hour charge for 2500 mAH cells) for 3-4 cells or up to 1800 mA for 1-2
> cells. And it comes with some decent (not fantastic) AA and AAA cells
> (4 of each) and AA to C and D adapters. I might even buy a second one
> sometime.

I have to agree about the Maha chargers. The often praised MH-C204F is
so slow with modern cell capacities that it does not induce the voltage
curves needed to detect a full charge. Its 500mA output was bordering
on too low even when the charger first came out. I have to turn mine
off manually on 2AH cells so I don't use it anymore.

The new MH-C204W manages 2A output but that's a risky rate when charging
batteries in pairs. I wouldn't trust it. Almost every other modern
fast charger powers and monitors batteries individually.
Anonymous
April 17, 2005 5:47:24 AM

Archived from groups: rec.photo.digital (More info?)

"Kevin McMurtrie" <mcmurtri@dslextreme.com> wrote in message
news:mcmurtri-7130A8.01264317042005@corp-radius.supernews.com...
> In article <LIn8e.337$Zi.14@fed1read04>,
> "Mark²" <mjmorgan(lowest even number here)@cox..net> wrote:
>
>> "Kevin McMurtrie" <mcmurtri@dslextreme.com> wrote in message
>> news:mcmurtri-9ECD30.21591716042005@corp-radius.supernews.com...
>> > In article <9no361l77vvd26ejlh43lhd29irjn2rurj@4ax.com>,
>> > curious@nospam.com wrote:
>> >
>> >> Nowadays alkaline batteries all seem to come with an expiration date
>> >> stamped
>> >> on them. Do NiMH batteries expire like alkaline batteries? I've
>> >> heard
>> >> that
>> >> NiMH batteries can be recharged up to 500-1000 times, but what if you
>> >> only
>> >> recharge them a few times a year, how long would they last?
>> >
>> > Despite what somebody else said in many posts, it is OK to let them run
>> > down. They're only damaged if the charges are unbalanced and the
>> > weaker
>> > cells become reverse charged by the stronger cells.
>>
>> Nobody (namely me) said anything against letting them "run down," but
>> prolonged "run down" storage can indeed deplete the batteries' ability to
>> hold a charge. I "run my batteries down" all the time...but I don't
>> leave
>> them in that state for long. I DO leave them in my flash until they
>> perform
>> poorly...then I charge them. I certainly wasn't trying to convey that
>> one
>> should ALWAYS charge them after ANY use. No.
>>
>> There are many differing advisements given from many different sources,
>> but
>> the consensus I've found (which also matches my personal experience)
>> supports the assertion that one should store charged batteries...and
>> definitely avoid storing depleted batteries.
>>
>> Batteries stored long term should be periodically charged (after several
>> months).
>
>
> Only lead-acid batteries need to be stored fully charged. LiIon and
> NiCd are actually damaged by periodic charging during storage. NiMH
> doesn't care about storage, so why bother?

We're talking about neither LiIon nor NiCd batteries.
Your last sentence makes no sense at all.
Perhaps one too many beers on a Saturday night?
:) 
Anonymous
April 17, 2005 6:00:21 AM

Archived from groups: rec.photo.digital (More info?)

"Kevin McMurtrie" <mcmurtri@dslextreme.com> wrote in message
news:mcmurtri-F30E2C.01471617042005@corp-radius.supernews.com...
> In article <7xfyxq0zcn.fsf@ruckus.brouhaha.com>,
> Paul Rubin <http://phr.cx@NOSPAM.invalid&gt; wrote:
>
>> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> > > You're actually better off keeping them fully charged.
>> > > My sets stay in their at all times (when not in use). *I've been
>> > > using
>> > > one particular set for nearly 5 years now (since late 2000), and they
>> > > still work fine--though they can't keep up with the newer,
>> > > high-capacity
>> > > units I've bought since (2300mAh vs much less).
>> > >
>> > > I would higly recommend Maha chargers from Thomas Distributing (along
>> > > with
>> > > their excellent PowerEx batteries).
>> >
>> > More to the point...
>> > Don't let your batteries become completely depleted.
>> > This will basically destroy them, or at best lead to their early
>> > demise.
>>
>> If you do leave the depleted for a long time, putting them through
>> several charge/discharge cycles will generally refresh them, though
>> maybe they're not as good as new afterwards.
>>
>> Maha stuff is not really that great. My favorite fancy AA charger
>> these days is the LaCrosse BC-900, also available from Thomas
>> Distributing. It has separate LCD displays for each cell so it
>> actually shows you the realtime charging voltage, and the measured
>> capacity of each cell. It has a discharge/refresh function that
>> repeatedly discharges and recharges the cell until the capacity stops
>> increasing. You can set the charge current up to 1000 mA (about a 3
>> hour charge for 2500 mAH cells) for 3-4 cells or up to 1800 mA for 1-2
>> cells. And it comes with some decent (not fantastic) AA and AAA cells
>> (4 of each) and AA to C and D adapters. I might even buy a second one
>> sometime.
>
> I have to agree about the Maha chargers. The often praised MH-C204F is
> so slow with modern cell capacities that it does not induce the voltage
> curves needed to detect a full charge. Its 500mA output was bordering
> on too low even when the charger first came out. I have to turn mine
> off manually on 2AH cells so I don't use it anymore.

I think you may have gotten hold of a lemon...because I have three 204F
chargers that work flawlessly with the 2300mA batteries that sit in them
this very moment. I haven't timed the recharge time, but they've never
failed to fully charge the batteries in a timely and standard fashion.



new MH-C204W manages 2A output but that's a risky rate when charging
> batteries in pairs. I wouldn't trust it. Almost every other modern
> fast charger powers and monitors batteries individually.
April 17, 2005 7:04:16 AM

Archived from groups: rec.photo.digital (More info?)

On 16 Apr 2005 23:36:57 -0700, Paul Rubin <http://phr.cx@NOSPAM.invalid&gt;
wrote:

>"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> Thus sayeth you... Maha chargers have kept old and new batteries
>> going strong for five years without fail. You are in a minority on
>> this one, as Maha chargers are roundly praised as excellent. -By
>> far the most recommended charger in terms of word-of-mouth over the
>> last several years.
>
>Try hanging out on some RC forums, which are populated by battery nerds
>like this place is populated by photo nerds. The Maha was last year's
>charger. That was then, this is now.

I too was under the assumption that the Maha chargers (and batteries too) were
the best. But if there's a new hot one, I'd like to hear about it... so
thanks for mentioning that Lacrosse. BTW, which RC forums would you be
referring too?
Anonymous
April 17, 2005 7:04:17 AM

Archived from groups: rec.photo.digital (More info?)

curious@nospam.com writes:
> I too was under the assumption that the Maha chargers (and batteries
> too) were the best. But if there's a new hot one, I'd like to hear
> about it... so thanks for mentioning that Lacrosse. BTW, which RC
> forums would you be referring too?

http://www.rcuniverse.com/forum/default.asp?fh=1 has a battery and
charger subforum, to name one.

As for the Lacrosse charger, I've only had it about a week but it's
been running almost continuously the whole time, doing
discharge/refresh. The analysis function is great since it tells you
exactly what the capacity of your cells are. They vary somewhat even
within a single package. For example, I have four 2200 mAH Energizer
cells (believed to be rebadged Sanyo HR-3U) and the capacities
measured at something like 2210, 2240, 2190, and 2270 mAH. So all
were slightly above spec except one of them fell short by a tiny
amount.

Guess what? I also tested eight Maha 1600 mAH cells and not a single
one of them measured above 1300 mAH. That's consistent with other
Maha tests I've seen. So, I think I'm through with Maha. I just
bought a big pile of HR-3U 2500's and the LaCrosse charger and also
the Energizer 15 minute charger (another amazing machine, just $25 at
Target including the four aforementioned 2200 mAH cells) and that
should be all the AA NiMH cells I need for quite a while except for
some possible special purpose ones.
Anonymous
April 17, 2005 7:04:18 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xu0m5naty.fsf@ruckus.brouhaha.com...
> curious@nospam.com writes:
>> I too was under the assumption that the Maha chargers (and batteries
>> too) were the best. But if there's a new hot one, I'd like to hear
>> about it... so thanks for mentioning that Lacrosse. BTW, which RC
>> forums would you be referring too?
>
> http://www.rcuniverse.com/forum/default.asp?fh=1 has a battery and
> charger subforum, to name one.
>
> As for the Lacrosse charger, I've only had it about a week but it's
> been running almost continuously the whole time, doing
> discharge/refresh. The analysis function is great since it tells you
> exactly what the capacity of your cells are. They vary somewhat even
> within a single package. For example, I have four 2200 mAH Energizer
> cells (believed to be rebadged Sanyo HR-3U) and the capacities
> measured at something like 2210, 2240, 2190, and 2270 mAH. So all
> were slightly above spec except one of them fell short by a tiny
> amount.
>
> Guess what? I also tested eight Maha 1600 mAH cells and not a single
> one of them measured above 1300 mAH. That's consistent with other
> Maha tests I've seen. So, I think I'm through with Maha. I just
> bought a big pile of HR-3U 2500's and the LaCrosse charger and also
> the Energizer 15 minute charger (another amazing machine, just $25 at
> Target including the four aforementioned 2200 mAH cells) and that
> should be all the AA NiMH cells I need for quite a while except for
> some possible special purpose ones.

I would wager that the 1600mAh cells you tested were far from new (who buys
1600mAh batteries any time recently??)
This would explain a lot about your readings since it is quite normal for
older batteries to generate smaller output.

BTW--I find it a little puzzling that you've expressed such strong advocacy
for a charger you have only a week's experience with.

I've been using my faithful Maha charger for approximately 312 times longer
than that (6 years).
:) 
Anonymous
April 17, 2005 7:04:19 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> I would wager that the 1600mAh cells you tested were far from new (who buys
> 1600mAh batteries any time recently??)
> This would explain a lot about your readings since it is quite normal for
> older batteries to generate smaller output.

The 1600 mAH cells had been sitting in a drawer for a couple years,
but they had never been used and were in an unopened package. Their
initial capacity before conditioning was only something like 400 mAH.
Post-conditioning they were in the 1200 mAH range. Other Maha tests
I've seen have gotten similar results.

> BTW--I find it a little puzzling that you've expressed such strong advocacy
> for a charger you have only a week's experience with.

I've had a Canon S100 digicam for almost as long as you've had your
Maha charger. I might get a Nikon D70 or something comparable soon.
I think I'll be able to tell in less than a week whether I like the
D70 better than the S100.

I don't know how the LaCrosse's long term durability is going to work
out but it's functionally superior to any other charger I've ever
used. Also, I bought it after following an extensive discussion about
it on a web forum, so I had a pretty good idea beforehand about what
it could do.
Anonymous
April 17, 2005 7:04:20 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xd5stn9yc.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> I would wager that the 1600mAh cells you tested were far from new (who
>> buys
>> 1600mAh batteries any time recently??)
>> This would explain a lot about your readings since it is quite normal for
>> older batteries to generate smaller output.
>
> The 1600 mAH cells had been sitting in a drawer for a couple years,
> but they had never been used and were in an unopened package. Their
> initial capacity before conditioning was only something like 400 mAH.
> Post-conditioning they were in the 1200 mAH range. Other Maha tests
> I've seen have gotten similar results.
>
>> BTW--I find it a little puzzling that you've expressed such strong
>> advocacy
>> for a charger you have only a week's experience with.
>
> I've had a Canon S100 digicam for almost as long as you've had your
> Maha charger. I might get a Nikon D70 or something comparable soon.
> I think I'll be able to tell in less than a week whether I like the
> D70 better than the S100.

That's a silly comparison.
Digital camera differences are immediately comparable and measurable in
feel, form, function and output, and various other measurable
characteristics.
Long-term battery-life, and the drawing of conslusions about a charger's
contribution or detriment to that long-term life (or lack there-of) is
something which simply cannot be determined in one week or even 20. Your
charger may well be the greatest thing going...or maybe not.

All I'm saying is...
....To speak from experience, one must first obtain some. :) 

> I don't know how the LaCrosse's long term durability is going to work
> out but it's functionally superior to any other charger I've ever
> used. Also, I bought it after following an extensive discussion about
> it on a web forum, so I had a pretty good idea beforehand about what
> it could do.

Good for you. I just found it surprising that after such strong
verbage...it turned out to be a brand new thing for you.
Anonymous
April 17, 2005 7:04:21 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> That's a silly comparison.
> Digital camera differences are immediately comparable and measurable in
> feel, form, function and output, and various other measurable
> characteristics.

Huh? The same is true of battery chargers. I won't know after a week
how durable the D70 is, but I'll be able to tell how useful its features
are and how good its pics are.

> Long-term battery-life, and the drawing of conslusions about a charger's
> contribution or detriment to that long-term life (or lack there-of) is
> something which simply cannot be determined in one week or even 20. Your
> charger may well be the greatest thing going...or maybe not.

I'm talking about the charger's features.
Anonymous
April 17, 2005 7:04:21 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> Good for you. I just found it surprising that after such strong
> verbage...it turned out to be a brand new thing for you.

NiMH batteries are not a new thing for me. I've been using them in
computers, cameras, and cell phones for more than a decade. I have
lots of experience with them. (Hint: none of them last for 500 cycles
as advertised). Recently I've had a burst of renewed interest in NiMH
chargers and bought several of them, because of some non-camera
gadgets that I've gotten recently that use them rather heavily.
Anonymous
April 17, 2005 7:04:22 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xhdi5u9i4.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> That's a silly comparison.
>> Digital camera differences are immediately comparable and measurable in
>> feel, form, function and output, and various other measurable
>> characteristics.
>
> Huh? The same is true of battery chargers. I won't know after a week
> how durable the D70 is, but I'll be able to tell how useful its features
> are and how good its pics are.
>
>> Long-term battery-life, and the drawing of conslusions about a charger's
>> contribution or detriment to that long-term life (or lack there-of) is
>> something which simply cannot be determined in one week or even 20. Your
>> charger may well be the greatest thing going...or maybe not.
>
> I'm talking about the charger's features.

:) 
Ah...but if you just look at "features," you might think the Sigma SD9 is a
great DSLR...

It's not really worth squabbling over.
You were just rather quick to dismiss the Maha, in spite of years of
fantastic service and years of top recommendations from a great many
sources, both personal, professional, and editorial. My tendency is to
question those who seem quick to dismiss industry standard-makers, which
meant I questioned you. Clearly you have some knowledge and some
experience. You just don't seem to have a great deal of temperance in your
pronouncements.
Anonymous
April 17, 2005 7:04:22 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xd5stu9fa.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> Good for you. I just found it surprising that after such strong
>> verbage...it turned out to be a brand new thing for you.
>
> NiMH batteries are not a new thing for me. I've been using them in
> computers, cameras, and cell phones for more than a decade. I have
> lots of experience with them. (Hint: none of them last for 500 cycles
> as advertised). Recently I've had a burst of renewed interest in NiMH
> chargers and bought several of them, because of some non-camera
> gadgets that I've gotten recently that use them rather heavily.

Since this is a photography forum, and since the particular needs/tendencies
in the use/charging/discharging of batteries can vary tremendously depending
on not only the device used and frequency of use, but also the manner and
frequency with which those batteries tend to be charged within those
different realms, I think that it is less-than-helpful to assume that the
particulars of battery charing/depletion/storage experience in one
application is necessarily indicative of the particulars of very different
application like flash/cameras.

Example: RC racing vs. camera/flash use have VERY different
charge/depletion issues/needs/challenges.
Anonymous
April 17, 2005 7:04:23 AM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> It's not really worth squabbling over.
> You were just rather quick to dismiss the Maha, in spite of years of
> fantastic service and years of top recommendations from a great many
> sources, both personal, professional, and editorial.

I prefer objective measurements and direct comparative evaluations to
the recommendations of those who keep using the same old stuff because
they haven't tried newer and better stuff.
Anonymous
April 17, 2005 7:04:24 AM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xpswt96im.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> It's not really worth squabbling over.
>> You were just rather quick to dismiss the Maha, in spite of years of
>> fantastic service and years of top recommendations from a great many
>> sources, both personal, professional, and editorial.
>
> I prefer objective measurements and direct comparative evaluations to
> the recommendations of those who keep using the same old stuff because
> they haven't tried newer and better stuff.

You just made a very large assumption.
Anonymous
April 17, 2005 7:38:15 AM

Archived from groups: rec.photo.digital (More info?)

On 16 Apr 2005 22:03:04 -0700, Paul Rubin
<http://phr.cx@NOSPAM.invalid&gt; wrote:

> You can set the charge current up to 1000 mA (about a 3 hour
> charge for 2500 mAH cells) for 3-4 cells or up to 1800 mA for
> 1-2 cells. And it comes with some decent (not fantastic) AA and
> AAA cells (4 of each) and AA to C and D adapters. I might even
> buy a second one sometime.

I had a similar charger several years ago that could charge any
number (1 to 4) of batteries ranging from AAA to D cells. It also
had a display that showed the battery voltages. The only problem
was that the larger the batteries and the more of them that were
being charged, the longer it would take. A couple of AAA or AA
batteries would charge relatively quickly. But try to charge 4 high
capacity D cells and it would take about 20 hours. And this was
with 4500 mah NiCad D cells. Do you know how long the BC-900 would
take to charge 4 9000 mah NiMH D cells?
Anonymous
April 17, 2005 7:38:16 AM

Archived from groups: rec.photo.digital (More info?)

ASAAR <caught@22.com> writes:
> I had a similar charger several years ago that could charge any
> number (1 to 4) of batteries ranging from AAA to D cells. It also
> had a display that showed the battery voltages. The only problem
> was that the larger the batteries and the more of them that were
> being charged, the longer it would take. A couple of AAA or AA
> batteries would charge relatively quickly. But try to charge 4 high
> capacity D cells and it would take about 20 hours. And this was
> with 4500 mah NiCad D cells. Do you know how long the BC-900 would
> take to charge 4 9000 mah NiMH D cells?

The BC-900 only charges AAA and AA cells. If you want a high capacity
D charger, try the AccuManager 20, also available from Thomas
Distributing. Charge time for 9000 mAH would be in the 14 hour range,
which isn't great.

I have a Great Planes Triton on order which charges at up to 5 amps,
so it can do a 9000 mAH D pack in a couple hours. It charges up to 24
cells at once. But it's a single channel charger, best for charging
sets of cells that have been used in the same device, not random cells
that might be in differing states of charge. It's probably not for
everyone. It costs about $100 (not including power supply) and its
operation is quite complex.
April 17, 2005 7:39:50 AM

Archived from groups: rec.photo.digital (More info?)

curious@nospam.com wrote:

> Nowadays alkaline batteries all seem to come with an expiration date
> stamped
> on them. Do NiMH batteries expire like alkaline batteries?

I bought a "new" NiMH battery for a 10 year old IBM laptop which was dated
on the package from 1998 and it works fine so I think it's more about
cycles than age.
--

Stacey
Anonymous
April 17, 2005 10:16:34 AM

Archived from groups: rec.photo.digital (More info?)

curious@nospam.com wrote:

: I wouldn't want to have batteries explode, and possibly cause a fire,
: if I left them in the charger and the power went out.

I have had a bank of cheap Ray-o-vac 1 hour chargers with their NIMH
batteries that are plugged in at all times. I store all my batteries in
the chargers, so they are always being trickle charged. There have been
several power interruptions (either from the Power co. or by my
disconnecting power to add another circuit) and there have never been any
instances of batteries heating up because of it. I guess that I may have
been lucky, but no signs of even a minor problem have been indicated. I
will continue to keep all my rechargables "topping up" in this way. I have
replaced older, lower mah batteries with newer higher mah ones a few
times. And I did have 1 battery that overheated a few years ago when the
device it was powering shorted out. But none of the batteries have ever
been damaged in the chargers (that I can see).

Randy

==========
Randy Berbaum
Champaign, IL
Anonymous
April 17, 2005 12:09:40 PM

Archived from groups: rec.photo.digital (More info?)

Paul Rubin wrote:
[]
> Guess what? I also tested eight Maha 1600 mAH cells and not a single
> one of them measured above 1300 mAH.

What was the guaranteed specification for the minimum (not average)
capacity, and when were the cells purchased? I expect you are aware that
cells are sold on the basis of a "typical" capacity and not the guaranteed
minimum.

David
Anonymous
April 17, 2005 12:09:41 PM

Archived from groups: rec.photo.digital (More info?)

"David J Taylor" <david-taylor@blueyonder.co.not-this-bit.nor-this-part.uk> writes:
> > Guess what? I also tested eight Maha 1600 mAH cells and not a single
> > one of them measured above 1300 mAH.
>
> What was the guaranteed specification for the minimum (not average)
> capacity, and when were the cells purchased? I expect you are aware that
> cells are sold on the basis of a "typical" capacity and not the guaranteed
> minimum.

I don't know what the guarantees are. I know that the Energizer cells
I've tested measured above their spec and the Maha cells I've tested
below their spec. Perhaps the Mahas were above their guarantee, or
perhaps no guarantee existed. It doesn't matter. And if a cell has a
capacity marked on the side and all eight cells that I test measure at
least 20% below that capacity, I'd say that capacity is something more
like "guaranteed to be lower than" and not "typical".

As mentioned, the Maha cells I tested were purchased about 2 years ago
and had been sitting in a drawer unused since that time. Other tests
by other people on more recent Maha cells got similar results to mine:
measurements considerably below the nominal capacity. Energizer and
Sanyo cells tested by both myself and others, by contrast, have
reached or exceeded their nominal capacity, or occasionally have
fallen short by a few percent. That includes the new 2500 mAH cells
which have been tested in some cases as high as 2800 mAH. I'm really
impressed by these cells and I have over 30 of them now.

FWIW, the 2200 mAH Energizers that I tested had "2050 mAH minimum" or
something like that in small letters. But in fact they all were much
better than that.
Anonymous
April 17, 2005 12:09:42 PM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7x7jj1ke6b.fsf@ruckus.brouhaha.com...
> "David J Taylor"
> <david-taylor@blueyonder.co.not-this-bit.nor-this-part.uk> writes:
>> > Guess what? I also tested eight Maha 1600 mAH cells and not a single
>> > one of them measured above 1300 mAH.
>>
>> What was the guaranteed specification for the minimum (not average)
>> capacity, and when were the cells purchased? I expect you are aware that
>> cells are sold on the basis of a "typical" capacity and not the
>> guaranteed
>> minimum.
>
> I don't know what the guarantees are. I know that the Energizer cells
> I've tested measured above their spec and the Maha cells I've tested
> below their spec. Perhaps the Mahas were above their guarantee, or
> perhaps no guarantee existed. It doesn't matter. And if a cell has a
> capacity marked on the side and all eight cells that I test measure at
> least 20% below that capacity, I'd say that capacity is something more
> like "guaranteed to be lower than" and not "typical".
>
> As mentioned, the Maha cells I tested were purchased about 2 years ago
> and had been sitting in a drawer unused since that time.

You are using incredibly poor logic here.

Earlier you state that old batteries...while they can be revived to a
certain degree...that they won't reach their the level they would have as
new. And yet you make your declaration and generalization about Maha
batteries (as poor) ONLY as a result of your tests of **2 year old batteries
that sat un-charged for the full two yeras!**

You then go on to declare that Mahas in general must therefore be poor
performers, well-below their stated rating based on your incredibly flawed
"test."

Complete madness, Paul.
You cannot make this declaration unless you throw out your own logic and
replace it with ignorance of even your own earlier statements.
Anonymous
April 17, 2005 12:09:43 PM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> Earlier you state that old batteries...while they can be revived to a
> certain degree...that they won't reach their the level they would have as
> new. And yet you make your declaration and generalization about Maha
> batteries (as poor) ONLY as a result of your tests of **2 year old batteries
> that sat un-charged for the full two yeras!**

I haven't seen any evidence that nimh cells don't come back to full
strength after conditioning. I said there is a theoretical
possibility that they might not. Others have said they do come back.

> You then go on to declare that Mahas in general must therefore be poor
> performers, well-below their stated rating based on your incredibly flawed
> "test."

Those test results are corroborated by other tests other people have done.
If you want to send me some more cells, I will test them.
Anonymous
April 17, 2005 12:46:43 PM

Archived from groups: rec.photo.digital (More info?)

Paul Rubin wrote:
> "David J Taylor"
> <david-taylor@blueyonder.co.not-this-bit.nor-this-part.uk> writes:
>>> Guess what? I also tested eight Maha 1600 mAH cells and not a
>>> single one of them measured above 1300 mAH.
>>
>> What was the guaranteed specification for the minimum (not average)
>> capacity, and when were the cells purchased? I expect you are aware
>> that cells are sold on the basis of a "typical" capacity and not the
>> guaranteed minimum.
>
> I don't know what the guarantees are. I know that the Energizer cells
> I've tested measured above their spec and the Maha cells I've tested
> below their spec. Perhaps the Mahas were above their guarantee, or
> perhaps no guarantee existed. It doesn't matter. And if a cell has a
> capacity marked on the side and all eight cells that I test measure at
> least 20% below that capacity, I'd say that capacity is something more
> like "guaranteed to be lower than" and not "typical".

I haven't seen histograms of capacity, but I would have hoped for not more
than a 20% total spread, so a 1600 mAh marked cell should be at least 1440
mAh. 1300 mAh is certainly disappointing. I've not been disappointed
with the Maha Powerex 1600 mAh cells I bought (some time ago) (marked
1600mAh typical, by the way, but not tested by me), nor with the MH-C204F
charger, but I see these as "good consumer level" brand rather than
"professional".

> As mentioned, the Maha cells I tested were purchased about 2 years ago
> and had been sitting in a drawer unused since that time. Other tests
> by other people on more recent Maha cells got similar results to mine:
> measurements considerably below the nominal capacity. Energizer and
> Sanyo cells tested by both myself and others, by contrast, have
> reached or exceeded their nominal capacity, or occasionally have
> fallen short by a few percent. That includes the new 2500 mAH cells
> which have been tested in some cases as high as 2800 mAH. I'm really
> impressed by these cells and I have over 30 of them now.
>
> FWIW, the 2200 mAH Energizers that I tested had "2050 mAH minimum" or
> something like that in small letters. But in fact they all were much
> better than that.

2050/2200 => 93%, so they are perhaps expecting a +/- 7% band. Not
unreasonable. I would be disappointed to find that Maha cells were
failing to live up to their specification - perhaps this is a recent
trend? These days I no longer use NiMH, as my recent cameras have Li-ion
batteries, which I do find more convenient for field use (all those AA
cells rolling around on the floor!), but I know they have an even more
limited life...

Cheers,
David
Anonymous
April 17, 2005 12:46:44 PM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> You seem to be forgetting the fact that he tested ONLY 2 year old Maha
> batteries that had to be repeatedly cycled to try and revive them.

Huh? Brand new cells fresh from the store also have to be repeatedly
cycled to reach full capacity. Everyone who uses NiMH cells knows that.
Anonymous
April 17, 2005 12:46:45 PM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xy8bhiwx0.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> You seem to be forgetting the fact that he tested ONLY 2 year old Maha
>> batteries that had to be repeatedly cycled to try and revive them.
>
> Huh? Brand new cells fresh from the store also have to be repeatedly
> cycled to reach full capacity. Everyone who uses NiMH cells knows that.

Sure!
-But manufacturers don't leave their new cells sitting for two years before
selling them.
Anonymous
April 17, 2005 12:46:46 PM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> Sure!
> -But manufacturers don't leave their new cells sitting for two years before
> selling them.

OK, I have some other 1600 mAH cells that are at least as old. I'll
put them on the BC900 and will post the results in a day or two (it
takes that long to run several cycles).
Anonymous
April 17, 2005 12:46:47 PM

Archived from groups: rec.photo.digital (More info?)

"Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
news:7xvf6lsq57.fsf@ruckus.brouhaha.com...
> "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>> Sure!
>> -But manufacturers don't leave their new cells sitting for two years
>> before
>> selling them.
>
> OK, I have some other 1600 mAH cells that are at least as old. I'll
> put them on the BC900 and will post the results in a day or two (it
> takes that long to run several cycles).

That's great, but I'm not sure you're getting the idea.
All NiMh batteries have their capacity to hold a charge diminish with age.
This can be effected by their state of charge during their life-time, but
the fact that they are also old will lead to lower readings compared with
new batteries.

If you want to make a declaration about Maha batteries in general, then you
need to remove the variables between the brands you intend to compare so
that brand is the lone variable. This would mean new batteries of the same
rating from the different brands. If all you're goingo to do is use some
"others" for comparison, this indicated nothing since the history of charges
and usage/activity'inactivity of any batteries you intend to compare will
nearly always introduce variables that cannot be quantified.
Anonymous
April 17, 2005 3:13:10 PM

Archived from groups: rec.photo.digital (More info?)

"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
> All NiMh batteries have their capacity to hold a charge diminish with age.
> This can be effected by their state of charge during their life-time, but
> the fact that they are also old will lead to lower readings compared with
> new batteries.

Why do you say that? Where is the evidence for it? Can you cite a
source? I'm not saying you're wrong but I haven't seen reliable info
either way. A few other people on this thread have said there's no
diminishment.

> If you want to make a declaration about Maha batteries in general, then you
> need to remove the variables between the brands you intend to compare so
> that brand is the lone variable. This would mean new batteries of the same
> rating from the different brands.

Yes, that's been done by other people who had new Maha cells. I don't
have any new Maha cells but I do have some old Yuasa cells (same age
as the Maha), so I'm running a test on those right now. That removes
the age variable the same way that using new cells does.

Of course if the Yuasas measure similarly to the Mahas, that doesn't
show an age-related effect, it can also mean that Yuasas also perform
below their spec, just like almost all NiMH brands do when they are
new. What I really want is some old Sanyo cells, but I don't have any.
So I'm doing what I can with what I have.
Anonymous
April 17, 2005 3:14:12 PM

Archived from groups: rec.photo.digital (More info?)

"David J Taylor" <david-taylor@blueyonder.co.not-this-bit.nor-this-part.uk> writes:
> Good point - I was assuming that his comparisons were all on an equal
> basis, but I see that is not so. It would be interesting to know how much
> capacity loss other brands suffer from similar storage conditions.

I have a test going on some Yuasa Delta cells that are about the same
age as the Mahas. Unfortunately I don't have any Sanyo cells of that
age. I might have some Lenmar cells if I can find them, and I'll test
those if they show up. I don't know who manufactures those.
Anonymous
April 17, 2005 3:40:44 PM

Archived from groups: rec.photo.digital (More info?)

Randy Berbaum wrote:
> curious@nospam.com wrote:
>
> : I wouldn't want to have batteries explode, and possibly cause a fire,
> : if I left them in the charger and the power went out.
>
> I have had a bank of cheap Ray-o-vac 1 hour chargers with their NIMH
> batteries that are plugged in at all times. I store all my batteries in
> the chargers, so they are always being trickle charged. There have been
> several power interruptions (either from the Power co. or by my
> disconnecting power to add another circuit) and there have never been any
> instances of batteries heating up because of it. I guess that I may have
> been lucky, but no signs of even a minor problem have been indicated. I
> will continue to keep all my rechargables "topping up" in this way. I have
> replaced older, lower mah batteries with newer higher mah ones a few
> times. And I did have 1 battery that overheated a few years ago when the
> device it was powering shorted out. But none of the batteries have ever
> been damaged in the chargers (that I can see).
>
> Randy
>
> ==========
> Randy Berbaum
> Champaign, IL
>
Randy,
Since 1hr chargers put a lot of current through the batteries, they
MUST have some method of sensing that the battery is charged, and
reducing the charge current. If they didn't, then they would probably
cause serious damage to the batteries, and/or a fire hazard.


--
Ron Hunter rphunter@charter.net
Anonymous
April 17, 2005 3:42:50 PM

Archived from groups: rec.photo.digital (More info?)

Mark² wrote:
> "Paul Rubin" <http://phr.cx@NOSPAM.invalid&gt; wrote in message
> news:7xfyxq0zcn.fsf@ruckus.brouhaha.com...
>
>>"Mark²" <mjmorgan(lowest even number here)@cox..net> writes:
>>
>>>>You're actually better off keeping them fully charged.
>>>>My sets stay in their at all times (when not in use). *I've been using
>>>>one particular set for nearly 5 years now (since late 2000), and they
>>>>still work fine--though they can't keep up with the newer,
>>>>high-capacity
>>>>units I've bought since (2300mAh vs much less).
>>>>
>>>>I would higly recommend Maha chargers from Thomas Distributing (along
>>>>with
>>>>their excellent PowerEx batteries).
>>>
>>>More to the point...
>>>Don't let your batteries become completely depleted.
>>>This will basically destroy them, or at best lead to their early demise.
>>
>>If you do leave the depleted for a long time, putting them through
>>several charge/discharge cycles will generally refresh them, though
>>maybe they're not as good as new afterwards.
>>
>>Maha stuff is not really that great.
>
>
> Thus sayeth you...
> Maha chargers have kept old and new batteries going strong for five years
> without fail.
> You are in a minority on this one, as Maha chargers are roundly praised as
> excellent.
> -By far the most recommended charger in terms of word-of-mouth over the last
> several years.
>
>
>>My favorite fancy AA charger
>>these days is the LaCrosse BC-900, also available from Thomas
>>Distributing. It has separate LCD displays for each cell so it
>>actually shows you the realtime charging voltage, and the measured
>>capacity of each cell. It has a discharge/refresh function that
>>repeatedly discharges and recharges the cell until the capacity stops
>>increasing. You can set the charge current up to 1000 mA (about a 3
>>hour charge for 2500 mAH cells) for 3-4 cells or up to 1800 mA for 1-2
>>cells. And it comes with some decent (not fantastic) AA and AAA cells
>>(4 of each) and AA to C and D adapters. I might even buy a second one
>>sometime.
>
>
> I think most folks don't prefer to carry on about such minutia.
> All that is great if you really feel it necessary to do all that fiddling.
> For me (and I think for most others), that is much ado about little...
> :) 
>
>
From reading this, and other newsgroups, the consensus seems to be that
Maha and Anasmann chargers are the best available for consumers.


--
Ron Hunter rphunter@charter.net
!