I can't wait that long to charge the batteries!

[Caspian]

Some domestic appliances come with rechargeable cells that need charging
for many hours before their first use.

For example, I have a Panasonic DECT phone with two AAA NiMH cells which
needs charging for 7 hours.

But maybe you can't wait that long for some reason and you simply
"must" use the appliance!

How much would cell life be reduced if such an appliance is used after,
say, only 30 to 60 minutes of charging instead of the 7 hours?

 

[Lostgallifreyan]

Caspian <zero@nomail.com> wrote in
news:46a87ac5$0$19518$8f2e0ebb@news.shared-secrets.com:

Some domestic appliances come with rechargeable cells that need charging
for many hours before their first use.

For example, I have a Panasonic DECT phone with two AAA NiMH cells which
needs charging for 7 hours.

But maybe you can't wait that long for some reason and you simply
"must" use the appliance!

How much would cell life be reduced if such an appliance is used after,
say, only 30 to 60 minutes of charging instead of the 7 hours?

First, take care that NiMH and NiCd are different, Nicads have a 'memory
effect' that makes this unwise. You've got Nickel metal hydrides, so you
can do it. Most of the charge goes in during the first part of the charge,
the increase isn't linear.

That means you can grab a useful charge in the first hour of charge, but to
make sure the full charge is properly applied, use up that charge before
trying to recharge, then give it the full time. Don't try to guess how much
is needed if you charge from empty for an hour, use for half an hour, and
such, you'll probably overcharge the batteries.

In short, you can get a lot of capacity from a charge of as little as one
third of the time for full charge, but whatever you do, always start the
charge on a freshly discharged MiMH battery so you know where you are.

 

[GregS]

In article <Xns9979863DC3052zoodlewurdle@140.99.99.130>, Lostgallifreyan <no-one@nowhere.net> wrote:

Caspian <zero@nomail.com> wrote in
news:46a87ac5$0$19518$8f2e0ebb@news.shared-secrets.com:

Some domestic appliances come with rechargeable cells that need charging
for many hours before their first use.

For example, I have a Panasonic DECT phone with two AAA NiMH cells which
needs charging for 7 hours.

But maybe you can't wait that long for some reason and you simply
"must" use the appliance!

How much would cell life be reduced if such an appliance is used after,
say, only 30 to 60 minutes of charging instead of the 7 hours?


First, take care that NiMH and NiCd are different, Nicads have a 'memory
effect' that makes this unwise. You've got Nickel metal hydrides, so you
can do it. Most of the charge goes in during the first part of the charge,
the increase isn't linear.

That means you can grab a useful charge in the first hour of charge, but to
make sure the full charge is properly applied, use up that charge before
trying to recharge, then give it the full time. Don't try to guess how much
is needed if you charge from empty for an hour, use for half an hour, and
such, you'll probably overcharge the batteries.

In short, you can get a lot of capacity from a charge of as little as one
third of the time for full charge, but whatever you do, always start the
charge on a freshly discharged MiMH battery so you know where you are.

I have done the quick test of a device sometimes without even plugging it
in, or after a short charge. I don't try to drain the device, and I never
seemed to have a problem. Here is a fairly neat page on battery effects......

http://www.dansdata.com/gz011.htm

greg

 

[Lostgallifreyan]

szekeres@pitt.edu (GregS) wrote in
news:f8a5r0$873$1@usenet01.srv.cis.pitt.edu:

I have done the quick test of a device sometimes without even plugging
it in, or after a short charge. I don't try to drain the device, and I
never seemed to have a problem. Here is a fairly neat page on battery
effects......

http://www.dansdata.com/gz011.htm

NiMH doesn't have memory effects so that's not an issue in my post.

I don't understand what you're saying exactly, but it's undeniable that if
you part-charge a NiMH battery during a third of its charge time, then
discharge only a little, you can't charge it for the full time unless it IS
drained first, for the obvious reason that you'll overcharge it if you try.
Some battery chargers might detect the true state of charge, but most
assume the battery is really low, and have a very simple timer, if there is
any means to prevent overcharge at all.

 

[GregS]

In article <Xns9979ACBD5DD58zoodlewurdle@140.99.99.130>, Lostgallifreyan <no-one@nowhere.net> wrote:

szekeres@pitt.edu (GregS) wrote in
news:f8a5r0$873$1@usenet01.srv.cis.pitt.edu:

I have done the quick test of a device sometimes without even plugging
it in, or after a short charge. I don't try to drain the device, and I
never seemed to have a problem. Here is a fairly neat page on battery
effects......

http://www.dansdata.com/gz011.htm


NiMH doesn't have memory effects so that's not an issue in my post.

I don't understand what you're saying exactly, but it's undeniable that if
you part-charge a NiMH battery during a third of its charge time, then
discharge only a little, you can't charge it for the full time unless it IS
drained first, for the obvious reason that you'll overcharge it if you try.
Some battery chargers might detect the true state of charge, but most
assume the battery is really low, and have a very simple timer, if there is
any means to prevent overcharge at all.

I have no idea what my chargers know.

I took my camera on vacation after not using it for a couple years and
used my older NiMH's. I charged them with two different chargers.
One charger would not stop charging. The camera would die very rapidly
using these cells. Allthough they are the highest capacity of the dozens
I own, I'm wondering if they are permanantely worthless, at least
in my camera. I was going to try some brand new cells and check
that first. I had to use Lithium backups on vacation for my Minolta.
I have a lot to learn about using NiMH cells,even though I have been
using them in cheap chargers for many years, but wish there was
something better.

I want to make a fixture to discharge my NiMH's down to 1 volt.
I was planning on using a diode string to generate a 1 volt zener and
using another series current limit resistor. Soon. I'm wondering
if that will help my current cells I own.

greg

 

[Lostgallifreyan]

szekeres@pitt.edu (GregS) wrote in
news:f8aq9t$cm0$2@usenet01.srv.cis.pitt.edu:

I had to use Lithium backups on vacation for my Minolta.

I've recently got a pair of small CR123A lithium rechargeables, 880 mAH.
Very nice. The charger cost a bit more than with NiMH types, but only maybe
50% more. Those batteries prefer to be discharged lightly and can be
recharged at will and taken off charge at any time for use, and the
chargers have to be accurate to sense the battery condition to be safe, so
if you can get one that's ok, you might get more out of them that with
NiMH. Less weight for a start.

The small chargers for 'SureFire' K2 LED torches found on eBay are worth a
go. I was nervous about mine at first, the risk of nasty accidents, but
it's well behaved and will safely stop charging when it's done. Each
cell is handled seperately by the charger. The cell charge voltage should
never rise above 4.2V for a 3.6V cell, and I think there are other critical
points to watch, but if these things increase in sales without a rise in
disaster reports, then all's good. It's dangerous tech, but so are NiMH's,
if they get a short circuit.

 

[Spurious Response]

Top posted just this once...

AT LAST! SOMEONE THAT SCTUALLY KNOW THE PROPER TERMS FOR THE DEVICES HE
USES!

Thanks dude... I needed that.

There, english TARDS.

Put that in you enema bag and shove it up your asses!


On Thu, 26 Jul 2007 12:01:43 +0100, Caspian <zero@nomail.com> wrote:

Some domestic appliances come with rechargeable cells that need charging
for many hours before their first use.

For example, I have a Panasonic DECT phone with two AAA NiMH cells which
needs charging for 7 hours.

But maybe you can't wait that long for some reason and you simply
"must" use the appliance!

How much would cell life be reduced if such an appliance is used after,
say, only 30 to 60 minutes of charging instead of the 7 hours?

 

[Spurious Response]

On Thu, 26 Jul 2007 12:11:48 GMT, Lostgallifreyan <no-one@nowhere.net>
wrote:

First, take care that NiMH and NiCd are different, Nicads have a 'memory
effect' that makes this unwise.

Wrong.

Single cells have ZERO "memory effect" when charged singularly.

A BATTERY of cells MAY develop a "memory effect".

Most modern charging systems incorporated into the devices the cells
are placed into themselves, however, have "watchdog circuits" that insure
that all cells get "topped off" properly.

You are about five years behind, as are the cell types you attribute
this "problem" to.

 

[Spurious Response]

On Thu, 26 Jul 2007 12:11:48 GMT, Lostgallifreyan <no-one@nowhere.net>
wrote:

In short, you can get a lot of capacity from a charge of as little as one
third of the time for full charge, but whatever you do, always start the
charge on a freshly discharged MiMH battery so you know where you are.

The "watchdog" circuit protect devices and cells from this problem as
well, these days. No overcharging here...

 

[Wilscombe]

On Jul 27, 5:10 am, Spurious Response
<SpuriousRespo...@cleansignal.org> wrote:

Top posted just this once...

AT LAST! SOMEONE THAT SCTUALLY KNOW THE PROPER TERMS FOR THE DEVICES HE
USES!

Thanks dude... I needed that.

There, english TARDS.

Put that in you enema bag and shove it up your asses!



On Thu, 26 Jul 2007 12:01:43 +0100, Caspian <z...@nomail.com> wrote:
Some domestic appliances come with rechargeable cells that need charging
for many hours before their first use.

For example, I have a Panasonic DECT phone with two AAA NiMH cells which
needs charging for 7 hours.

But maybe you can't wait that long for some reason and you simply
"must" use the appliance!

How much would cell life be reduced if such an appliance is used after,
say, only 30 to 60 minutes of charging instead of the 7 hours?- Hide quoted text -

- Show quoted text -

A simple solution might be to use standard disposable AAA batteries
until the others are fully charged. There might be a problem if these
batteries are left in for a long time but I imagine the risk would be
minimal. Most manufacturers have Helplines who could advise.
Can anyone tell me what a "Tard" is,let alone an English one? I
imagine "Spurious Response" is a Redneck? Curious breed!

 

[Lostgallifreyan]

Spurious Response <SpuriousResponse@cleansignal.org> wrote in
news:t2sia39cq6kk8b9chur83p91rse4cav800@4ax.com:

On Thu, 26 Jul 2007 12:11:48 GMT, Lostgallifreyan <no-one@nowhere.net
wrote:

First, take care that NiMH and NiCd are different, Nicads have a 'memory
effect' that makes this unwise.


Wrong.

Single cells have ZERO "memory effect" when charged singularly.

A BATTERY of cells MAY develop a "memory effect".

Most modern charging systems incorporated into the devices the cells
are placed into themselves, however, have "watchdog circuits" that insure
that all cells get "topped off" properly.

You are about five years behind, as are the cell types you attribute
this "problem" to.

"Voltage Depression occurs primarily in NiCad batteries. NiMH batteries are
almost never affected and Li-Ion batteries are NEVER affected."
http://www.zbattery.com/memoryeffect.html

I was partially remembering this:
"If a cell becomes reverse-charged, or is left flat for a long time, small
metal whiskers can grow across the plates."
http://cucc.survex.com/archive/jnl/1992/nicd.htm
I remember that partial formation of those 'whiskers' can be related to
partial charge/discharge cycles.

If the OP had asked questions about memory effect specifically, I'd have
checked for current info before posting, but he didn't ask that. It's a
side issue, as he asked if his NiMH's can be safely part charged then used.
I think my answers to the actual question were right.

 

[Lostgallifreyan]

Spurious Response <SpuriousResponse@cleansignal.org> wrote in
news8sia31tfi6ek9qkt8sdc2bljc7dgdokdr@4ax.com:

On Thu, 26 Jul 2007 12:11:48 GMT, Lostgallifreyan <no-one@nowhere.net
wrote:

In short, you can get a lot of capacity from a charge of as little as
one third of the time for full charge, but whatever you do, always
start the charge on a freshly discharged MiMH battery so you know
where you are.


The "watchdog" circuit protect devices and cells from this problem
as
well, these days. No overcharging here...

It would if it had one, perhaps. If all it has is a timer, the obvious
thing to do is charge for full time on a freshly discharged cell. If there
really IS a non-obvious and different method, I'm not sure it's wise to
recommend it to someone asking a very basic question about battery charge.
Far better to take the safest course.

 

[GregS]

In article <Xns997A7278F40ECzoodlewurdle@140.99.99.130>, Lostgallifreyan <no-one@nowhere.net> wrote:

Spurious Response <SpuriousResponse@cleansignal.org> wrote in
news:t2sia39cq6kk8b9chur83p91rse4cav800@4ax.com:

On Thu, 26 Jul 2007 12:11:48 GMT, Lostgallifreyan <no-one@nowhere.net
wrote:

First, take care that NiMH and NiCd are different, Nicads have a 'memory
effect' that makes this unwise.


Wrong.

Single cells have ZERO "memory effect" when charged singularly.

A BATTERY of cells MAY develop a "memory effect".

Most modern charging systems incorporated into the devices the cells
are placed into themselves, however, have "watchdog circuits" that insure
that all cells get "topped off" properly.

You are about five years behind, as are the cell types you attribute
this "problem" to.


"Voltage Depression occurs primarily in NiCad batteries. NiMH batteries are
almost never affected and Li-Ion batteries are NEVER affected."
http://www.zbattery.com/memoryeffect.html

I was partially remembering this:
"If a cell becomes reverse-charged, or is left flat for a long time, small
metal whiskers can grow across the plates."

Partially true. Only if the cell is abused, especially overcgarging, or
perhaps if its been used a lot. I have let cells lie around and they
don't go bad. I have had cells practically brand new that shorted
after harsh charging. I am referring to NiCad's.

Yes, my Johnson walkie talkies still have German Nicads that still
work, and never go dead. I charged them a couple years ago. They
are 43 years old.

greg

 

[clifto]

Wilscombe wrote:

Can anyone tell me what a "Tard" is,let alone an English one? I
imagine "Spurious Response" is a Redneck? Curious breed!

It's short for "retard", which itself is shorthand for "mentally retarded
person".

--
"Liberals used to be the ones who argued that sending U.S. troops abroad
was a small price to pay to stop genocide; now they argue that genocide
is a small price to pay to bring U.S. troops home."
-- Jonah Goldberg

 

[Terran Melconian]

On 2007-07-26, Caspian <zero@nomail.com> wrote:

Some domestic appliances come with rechargeable cells that need charging
for many hours before their first use.

For example, I have a Panasonic DECT phone with two AAA NiMH cells which
needs charging for 7 hours.

I have often wondered that myself. I see this warning ONLY with
consumer appliances. When I buy cells, the data sheet never says
anything about needing to charge them fully before the first use in
order to avoid some sort of permanent damage or capacity reduction.

I have since ignored the warnings about needing a full charge before
first use, with no observed ill effects.

 

[Spurious Response]

On Fri, 27 Jul 2007 13:30:21 -0500, clifto <clifto@gmail.com> wrote:

Wilscombe wrote:
Can anyone tell me what a "Tard" is,let alone an English one? I
imagine "Spurious Response" is a Redneck? Curious breed!

It's short for "retard", which itself is shorthand for "mentally retarded
person".

Nope. The term retard can be referring to such a person, but it also
means taking a step back.

Take some techno-person, watch him state something utterly ludicrous,
and just like the "retarded" timing on an automobile, viola! We have
someone that is acting retarded.

They are rampant in Usenet.

 

[Jerry G.]

Have several sets of batteries with external chargers. While you are
gabbing away on your phone, you can be having some batteries on charge.
When the batteries in use are running low, you do a battery swap.
Calculate the number of sets of batteries and chargers you will need,
and then go for it!

By the way it sounds, I would guess you will need three sets of
batteries and chargers.

--

Jerry G.


"Caspian" <zero@nomail.com> wrote in message
news:46a87ac5$0$19518$8f2e0ebb@news.shared-secrets.com...
Some domestic appliances come with rechargeable cells that need charging
for many hours before their first use.

For example, I have a Panasonic DECT phone with two AAA NiMH cells which
needs charging for 7 hours.

But maybe you can't wait that long for some reason and you simply
"must" use the appliance!

How much would cell life be reduced if such an appliance is used after,
say, only 30 to 60 minutes of charging instead of the 7 hours?

 

[Spurious Response]

On Sat, 28 Jul 2007 15:05:24 -0400, "Jerry G."
<jerryg50@NOSPAMhotmail.com> wrote:

Have several sets of batteries with external chargers.

No. You have several cell in external charging devices, which been
improperly monikered as "battery" chargers.

While you are
gabbing away on your phone, you can be having some batteries on charge.

No. You have some cells on charge.

When the batteries in use are running low, you do a battery swap.

When the cells run low, you should swap ALL of the CELLS that comprise
your device's BATTERY, as swapping only those you perceive as being
drained is asking for problems.

Calculate the number of sets of batteries and chargers you will need,
and then go for it!

Unrelated stupid shit.

By the way it sounds, I would guess you will need three sets of
batteries and chargers.

Unrelated stupid shit.

 

[Lostgallifreyan]

Spurious Response <SpuriousResponse@cleansignal.org> wrote in
news:gvnoa3loa2ollhdp4747j1lf1e5tpqcces@4ax.com:

On Sat, 28 Jul 2007 15:05:24 -0400, "Jerry G."
jerryg50@NOSPAMhotmail.com> wrote:

A snipped, and annoying, lecture on the distinction between 'cell' and
'battery'.

If it excercises you so much, instead of lambasting someone just because
you can, write a letter to the Times or something. Submit an article to a
journal. Or at least write to every maker of commercial gear who
transgresses. There's more to understanding something than getting the
exact words right. Sure it's misleading, but most people know how to avoid
the problems. If you really want to evangelise on this point, get a job
writing manuals for a major company, as that's the way you'll most likely
shape public usage of these terms. You certainly won't reach them this way.

 

[Spurious Response]

On Sun, 29 Jul 2007 11:10:35 GMT, Lostgallifreyan <no-one@nowhere.net>
wrote:

Spurious Response <SpuriousResponse@cleansignal.org> wrote in
news:gvnoa3loa2ollhdp4747j1lf1e5tpqcces@4ax.com:

On Sat, 28 Jul 2007 15:05:24 -0400, "Jerry G."
jerryg50@NOSPAMhotmail.com> wrote:

A snipped, and annoying, lecture on the distinction between 'cell' and
'battery'.

If it excercises you so much, instead of lambasting someone just because
you can, write a letter to the Times or something. Submit an article to a
journal. Or at least write to every maker of commercial gear who
transgresses. There's more to understanding something than getting the
exact words right. Sure it's misleading, but most people know how to avoid
the problems. If you really want to evangelise on this point, get a job
writing manuals for a major company, as that's the way you'll most likely
shape public usage of these terms. You certainly won't reach them this way.

Learn how to attribute your quoting correctly, and/or quote the actual
post you are replying to.