Nicad battery charging rate/capacity

[Andrew]

I have a rechargable electric razor, which contains two AA size 60mAh Nicad
cells. As such cells do these have recently lost their ability to hold
their charge so I have replaced them.

The razor also acts as a charger when plugged into the mains. When I
purchased the replacement celss I noted that I could have bought 2000mAh
batteries which, presumably, would have lasted ~3 times longer before
needing recharging.

In the event I used 600mAh batteries, the same as the originals since I was
uncertain of the razor's charging circuit's ability to handle these. Would
using a larger capacity battery have caused any problems? Does having a
higher capacity mean that a different charger circuit is required or would
it have happily worked, albeit it would have taken longer to recharge?

 

[Rheilly Phoull]

"Andrew" <ajhuk@hotmail.com> wrote in message
news:c36f3s$21pefg$1@ID-197877.news.uni-berlin.de...

I have a rechargable electric razor, which contains two AA size 60mAh
Nicad
cells. As such cells do these have recently lost their ability to hold
their charge so I have replaced them.

The razor also acts as a charger when plugged into the mains. When I
purchased the replacement celss I noted that I could have bought 2000mAh
batteries which, presumably, would have lasted ~3 times longer before
needing recharging.

In the event I used 600mAh batteries, the same as the originals since I
was
uncertain of the razor's charging circuit's ability to handle these.
Would
using a larger capacity battery have caused any problems? Does having a
higher capacity mean that a different charger circuit is required or would
it have happily worked, albeit it would have taken longer to recharge?



I would think that it would simply take longer to charge the higher capacity

cells, I can't see a problem with fitting higher capacity cells.


--
Regards ........ Rheilly Phoull

 

[John Woodgate]

I read in sci.electronics.design that Andrew <ajhuk@hotmail.com> wrote
(in <c36f3s$21pefg$1@ID-197877.news.uni-berlin.de&gt about 'Nicad battery
charging rate/capacity', on Tue, 16 Mar 2004:

Does
having a higher capacity mean that a different charger circuit is
required or would it have happily worked, albeit it would have taken
longer to recharge?

Just longer to recharge if the new batteries use the same chemistry as
the old one. But don't change NiCd to NiMH.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Terry Given]

"John Woodgate" <jmw@jmwa.demon.contraspam.yuk> wrote in message
news:As$VN8E9JvVAFwBQ@jmwa.demon.co.uk...

I read in sci.electronics.design that Andrew <ajhuk@hotmail.com> wrote
(in <c36f3s$21pefg$1@ID-197877.news.uni-berlin.de&gt about 'Nicad battery
charging rate/capacity', on Tue, 16 Mar 2004:
Does
having a higher capacity mean that a different charger circuit is
required or would it have happily worked, albeit it would have taken
longer to recharge?

Just longer to recharge if the new batteries use the same chemistry as
the old one. But don't change NiCd to NiMH.
--

had a quick browse through:

Rechargeable Batteries applications handbook, Gates energy products, and
yep, all will be fine, other than it will take longer to charge. Actually,
all of the relevant parameters (cell temperature, pressure etc.) will
improve (ie reduce) at the reduced charge rate (known as the "C" rate -
fraction of rated current).