Recharging Ni-MH battaries - how long it is supposed to ta..

The battery charger determines the charge time. Some I've seen, say
15 hours, some say 4 hours, and some say 2 hours.

The quick charge battery chargers will heat up the batteries quite
hot.

PJ




On Wed, 17 Dec 2003 22:08:53 +0200, ddtl <this.is@invalid> wrote:

 >
 >Hello everybody,
 >
 >Recently i have bought a new digital camera, and rechargeable AA Ni-MH
 >batteries for it.
 >
 >The question is, how long it is supposed to take to fully recharge those
 >batteries? Those Ni-MH batteries are 2150mAh, and i have only a regular
 >recharger, usually used for recharging 500-700mAh batteries (500-700mAh
 >batteries have to be charged for 8 hours, or at least that is what i have done
 >till now).
 >
 >The charger has the following written on it:
 >
 >PRI: 220V AC 50Hz~7W
 >SEC: 130mA MAX --- 1.5V
 > 30mA MAX --- 9V
 >
 >What does that means - as i understand, it means that the recharger charges
 >130mA per hour, that is: it will take 16-17 hours to recharge 2150 battery,
 >am i right?
 >
 >Also, is there is any difference whether one or (for example) four batteries are
 >recharged at the same time? Somebody supposed to me that 130mA means that
 >recharger yields 130mA per hour totally and not per battery. Is that so?
 >
 >The instructions on the batteries themselves are in Japanese only, so i cannot
 >understand them.
 >
 >ddtl.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

My Radioshack charger takes 13 hrs to charge four radioshack batteries.

I also have an Olympus fast charger that only takes two hours to charge
four batteries. Al are 1500mh 1.2vdc.



http://community-2.webtv.net/GEOH/FKEYS/
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 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

Because the batteries have three times the capacity of your nicads, it will
take three times longer to charge, or approximately 24 hours. It would only
take 17 hours if there were no losses in the charging system, but to get
100% of rating out of a battery, you need to put in about 130% to 140% of
the energy. The extra 30% to 40% is transformed to heat during the charging
process.

"ddtl" <this.is@invalid> wrote in message
news:4lc1uv4ic1d1221tb37vc29grhbap35a61@4ax.com...
 >
 > Hello everybody,
 >
 > Recently i have bought a new digital camera, and rechargeable AA Ni-MH
 > batteries for it.
 >
 > The question is, how long it is supposed to take to fully recharge those
 > batteries? Those Ni-MH batteries are 2150mAh, and i have only a regular
 > recharger, usually used for recharging 500-700mAh batteries (500-700mAh
 > batteries have to be charged for 8 hours, or at least that is what i have
done
 > till now).
 >
 > The charger has the following written on it:
 >
 > PRI: 220V AC 50Hz~7W
 > SEC: 130mA MAX --- 1.5V
 > 30mA MAX --- 9V
 >
 > What does that means - as i understand, it means that the recharger
charges
 > 130mA per hour, that is: it will take 16-17 hours to recharge 2150
battery,
 > am i right?
 >
 > Also, is there is any difference whether one or (for example) four
batteries are
 > recharged at the same time? Somebody supposed to me that 130mA means that
 > recharger yields 130mA per hour totally and not per battery. Is that so?
 >
 > The instructions on the batteries themselves are in Japanese only, so i
cannot
 > understand them.
 >
 > ddtl.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

On Wed, 17 Dec 2003 22:08:53 +0200, ddtl <this.is@invalid> wrote:

 >
 >Hello everybody,
 >
 >Recently i have bought a new digital camera, and rechargeable AA Ni-MH
 >batteries for it.
 >
 >The question is, how long it is supposed to take to fully recharge those
 >batteries? Those Ni-MH batteries are 2150mAh, and i have only a regular
 >recharger, usually used for recharging 500-700mAh batteries (500-700mAh
 >batteries have to be charged for 8 hours, or at least that is what i have done
 >till now).

all you would ever want to know about batteries is ..here HTH

<a style='text-decoration: underline;' href="http://www.batteryuniversity.com/" target="_blank">http://www.batteryuniversity.com/</a><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

Very interesting link - thanks.

ddtl


 >all you would ever want to know about batteries is ..here HTH
 >
 >http://www.batteryuniversity.com/<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

On Wed, 17 Dec 2003 22:08:53 +0200, ddtl <this.is@invalid> wrote
something
.......and in reply I say!:

Your charger will take (2150 * number of batteries) / 130. So four
batteries will take 70 hours at least. In fact it will take more, as
the batteries take more than their capacity by nearly half to fully
charge.

To put it another way, your NiCds were about 300mAH, and took all day
to charge 4 batteries. NiMH are 7 times that.

If you have a digicam, then I suggest you get a better charger. I know
this just says "spend more money". But there are chargers out there
that are quite cheap now for NiMH (I bought one in Aust for Aud$45)
that charge within 2 hours. The one I bought is by PowerBase. It
senses battery charge and stops charging when the batteries are full.
IT does this properly, in that it's not just timer based. I have
checked and if the batts are half flat only, it takes less time to
turn off.

I bought one without batteries, because the one with bundled
batteries had the wrong size for my use at the time. If you buy with
bundled batteries then it will cost extra, of course.

 >
 >Hello everybody,
 >
 >Recently i have bought a new digital camera, and rechargeable AA Ni-MH
 >batteries for it.
 >
 >The question is, how long it is supposed to take to fully recharge those
 >batteries? Those Ni-MH batteries are 2150mAh, and i have only a regular
 >recharger, usually used for recharging 500-700mAh batteries (500-700mAh
 >batteries have to be charged for 8 hours, or at least that is what i have done
 >till now).
 >
 >The charger has the following written on it:
 >
 >PRI: 220V AC 50Hz~7W
 >SEC: 130mA MAX --- 1.5V
 > 30mA MAX --- 9V
 >
 >What does that means - as i understand, it means that the recharger charges
 >130mA per hour, that is: it will take 16-17 hours to recharge 2150 battery,
 >am i right?
 >
 >Also, is there is any difference whether one or (for example) four batteries are
 >recharged at the same time? Somebody supposed to me that 130mA means that
 >recharger yields 130mA per hour totally and not per battery. Is that so?
 >
 >The instructions on the batteries themselves are in Japanese only, so i cannot
 >understand them.
 >
 >ddtl.

**************************************************** sorry
remove ns from my header address to reply via email

I was frightened by the idea of a conspiracy that was
causing it all.
But then I was terrified that maybe there was no plan,
really. Is this unpleasant mess all a mistake?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

On Fri, 19 Dec 2003 21:18:50 +0800, Old Nick <nsnfwhite.RemoveThis@iinet.net.au>
wrote:

 >On Wed, 17 Dec 2003 22:08:53 +0200, ddtl <this.is@invalid> wrote
 >something
 >......and in reply I say!:
 >
 >Your charger will take (2150 * number of batteries) / 130. So four
 >batteries will take 70 hours at least. In fact it will take more, as
 >the batteries take more than their capacity by nearly half to fully
 >charge.

That may be a very simplistic assumption by believing that all cells
are wired in series ..
My Ansmann Powerline4 charges 4 batteries at 700mAh which in yr logic
should take 2100*4/700 = 12hrs .. yet it charges empty battieries in
approx 4 hours .. all 4 of them .. being (approx. 2100/700)*1,4 ...
1,4 being the charging "loss" factor ..<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

On Fri, 19 Dec 2003 15:09:25 +0100, imbsysop <imbsysop.TakeThisOut@yahoo.com>
wrote something
.......and in reply I say!:

 >That may be a very simplistic assumption by believing that all cells
 >are wired in series ..

Parallel actually. In series the volts are added, and therefore the
supplied power is the added volts times the claimed current, with each
cell receiving the claimed current, at the charging voltage divied by
the number of cells. In parallel the amps are added and the supplied
power would be the voltage of one cell, with the current being shared
among the cells.

I suppose it depends on whether you have to have more than one cell in
there to allow charging. If so, then you are correct. The charger is
passing a multiple of each cell's voltage through more than one cell,
and will charge according to the charging current.

The OP stated that the charger put out 1.5V @ 130mA, so I assumed that
it would work in parallel, and perform as I said.

 >My Ansmann Powerline4 charges 4 batteries at 700mAh which in yr logic
 >should take 2100*4/700 = 12hrs .. yet it charges empty battieries in
 >approx 4 hours .. all 4 of them .. being (approx. 2100/700)*1,4 ...
 >1,4 being the charging "loss" factor ..

**************************************************** sorry
remove ns from my header address to reply via email

I was frightened by the idea of a conspiracy that was
causing it all.
But then I was terrified that maybe there was no plan,
really. Is this unpleasant mess all a mistake?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta.. 

will the charger do NiMH as the older one won't and could damage them
£20 got me a 2-3 hours charger and 4x 2100mah batteries from Maplin

Simon

"Old Nick" <nsnfwhite DeleteThis @iinet.net.au> wrote in message
news:7jjauvkepce2gc1k1g4i77bqe7hs7iqm9u@4ax.com...
 > On Fri, 19 Dec 2003 15:09:25 +0100, imbsysop <imbsysop DeleteThis @yahoo.com>
 > wrote something
 > ......and in reply I say!:
 >
  > >That may be a very simplistic assumption by believing that all cells
  > >are wired in series ..
 >
 > Parallel actually. In series the volts are added, and therefore the
 > supplied power is the added volts times the claimed current, with each
 > cell receiving the claimed current, at the charging voltage divied by
 > the number of cells. In parallel the amps are added and the supplied
 > power would be the voltage of one cell, with the current being shared
 > among the cells.
 >
 > I suppose it depends on whether you have to have more than one cell in
 > there to allow charging. If so, then you are correct. The charger is
 > passing a multiple of each cell's voltage through more than one cell,
 > and will charge according to the charging current.
 >
 > The OP stated that the charger put out 1.5V @ 130mA, so I assumed that
 > it would work in parallel, and perform as I said.
 >
  > >My Ansmann Powerline4 charges 4 batteries at 700mAh which in yr logic
  > >should take 2100*4/700 = 12hrs .. yet it charges empty battieries in
  > >approx 4 hours .. all 4 of them .. being (approx. 2100/700)*1,4 ...
  > >1,4 being the charging "loss" factor ..
 >
 > **************************************************** sorry
 > remove ns from my header address to reply via email
 >
 > I was frightened by the idea of a conspiracy that was
 > causing it all.
 > But then I was terrified that maybe there was no plan,
 > really. Is this unpleasant mess all a mistake?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Recharging Ni-MH battaries - how long it is supposed to ta..