Rechargeable Alkaline v NiMh

[Gordon Levi]

Some of my gadgets, notably a shaver and a TV remote, seem to work
better with alkaline rather than NiMh batteries. I have a weather
station that instructs me not to use "rechargeable" batteries.

Can I assume that the difference is the higher voltage provided by
alkaline batteries and that the weather station would be content with
rechargeable alkaline batteries?

And a few more questions if I may-
When would I use NiMh batteries in preference to rechargeable alkaline
ones?

What is the difference between NiMh and alkaline chargers?

My mains powered alkaline battery charger has a switch to set alkaline
or NiMh. What does changing the switch position do?

My USB powered alkaline battery charger does not have a similar
switch. How does it "know"?
<http://www.amazon.com/iGo-AC05105-0001-2-Port-Battery-Charger/dp/B004XT6HW4>.

And yes, I have Googled but was overwhelmed by information on
recharging _non_-rechargeable alkaline batteries.

 

[Phil Allison]

Gordon Levi wrote:

Some of my gadgets, notably a shaver and a TV remote, seem to work
better with alkaline rather than NiMh batteries. I have a weather
station that instructs me not to use "rechargeable" batteries.

** NiMH cells have a lower terminal voltage and high self discharge rates - making them unsuitable for applications that do not require high current or where a long time span between replacement is important, like a wall clock.

Can I assume that the difference is the higher voltage provided by
alkaline batteries and that the weather station would be content with
rechargeable alkaline batteries?

** Rechargeable alkalines come in different chemistries - what is true of one is not true of another.

And a few more questions if I may-
When would I use NiMh batteries in preference to rechargeable alkaline
ones?

** NiMH can give very high current for short times - so are best in digital cameras and other high current applications.


> What is the difference between NiMh and alkaline chargers?

** There is no consistent difference, NiMH chargers vary enormously and so do ones for alkalines.

My mains powered alkaline battery charger has a switch to set alkaline
or NiMh. What does changing the switch position do?

** Stupid question, we do not even know what charger you have.

My USB powered alkaline battery charger does not have a similar
switch. How does it "know"?
http://www.amazon.com/iGo-AC05105-0001-2-Port-Battery-Charger/dp/B004XT6HW4>.

** How do you know it does?

It may well charge the both in the same way, seeing as only one rather special type of alkaline cell is specified.



.... Phil

 

[Phil Allison]

~misfit~ wrote:

Phil Allison wrote:
Gordon Levi wrote:

Some of my gadgets, notably a shaver and a TV remote, seem to work
better with alkaline rather than NiMh batteries. I have a weather
station that instructs me not to use "rechargeable" batteries.


** NiMH cells have a lower terminal voltage and high self discharge
rates - making them unsuitable for applications that do not require
high current or where a long time span between replacement is
important, like a wall clock.

Not completely true about high self discharge rates. There is an increasing
amount of 'LSD' NiMH cells. Eneloop started the trend but I've seen at least
five other major manufacturers have followed suit. (I have some Varta and
Panasonic LSDs along with a heap of Eneloops.) I use them in everything from
remotes and wall clocks to LED flashlights and my camera. They last between
two and three years in remotes and I can't tell you in the wall clock as
it's already gone for three years, longer than an alkaline cell would have.

** Alkaline AA and AAA cells still have more energy capacity AND much slower self discharge than Eneloops for about 1/4 the price.

For flashlights and cameras - use Eneloops, but for wall clocks or TV remotes it's nuts.


..... Phil

 

[Trevor Wilson]

On 22/03/2015 12:59 AM, Gordon Levi wrote:

Some of my gadgets, notably a shaver and a TV remote, seem to work
better with alkaline rather than NiMh batteries. I have a weather
station that instructs me not to use "rechargeable" batteries.

Can I assume that the difference is the higher voltage provided by
alkaline batteries and that the weather station would be content with
rechargeable alkaline batteries?

**Yep.

And a few more questions if I may-
When would I use NiMh batteries in preference to rechargeable alkaline
ones?

**Rechargeable alkalines are not as rechargeable as NiMh or other
secondary cells. IOW: Whilst an NiMH cell may be able to be recharged up
to 1,000 times, a rechargeable alkaline (NOTE: Not all alkalines can be
recharged) may only see 10 or 15 recharges.

What is the difference between NiMh and alkaline chargers?

**I've not examined them in detail, but, since alkalines have a terminal
Voltage of more than 1.5 Volts and NiMH cells are more like 1.2 Volts, I
suspect that may be a big part of it.

My mains powered alkaline battery charger has a switch to set alkaline
or NiMh. What does changing the switch position do?

**Dunno. See above.

My USB powered alkaline battery charger does not have a similar
switch. How does it "know"?
http://www.amazon.com/iGo-AC05105-0001-2-Port-Battery-Charger/dp/B004XT6HW4>.

**It is likely the device can sense the terminal Voltage and make the
appropriate internal adjustments. For instance: An NiMH cell would
likely be considered fully discharged with a terminal Voltage of around
1.1 Volts. An alkaline would likely be considered fully discharged with
a terminal Voltage of around 1.3 Volts. As I recall, when I used some
alkaline rechargeables about 20 years ago (Ray-O-Vac brand), there was a
very specific warning not to allow the terminal Voltage to fall too low.
Otherwise effective recharging was impossible.

And yes, I have Googled but was overwhelmed by information on
recharging _non_-rechargeable alkaline batteries.

--
Trevor Wilson
www.rageaudio.com.au

---
This email has been checked for viruses by Avast antivirus software.
http://www.avast.com

 

[~misfit~]

Once upon a time on usenet Phil Allison wrote:

Gordon Levi wrote:

Some of my gadgets, notably a shaver and a TV remote, seem to work
better with alkaline rather than NiMh batteries. I have a weather
station that instructs me not to use "rechargeable" batteries.


** NiMH cells have a lower terminal voltage and high self discharge
rates - making them unsuitable for applications that do not require
high current or where a long time span between replacement is
important, like a wall clock.

Not completely true about high self discharge rates. There is an increasing
amount of 'LSD' NiMH cells. Eneloop started the trend but I've seen at least
five other major manufacturers have followed suit. (I have some Varta and
Panasonic LSDs along with a heap of Eneloops.) I use them in everything from
remotes and wall clocks to LED flashlights and my camera. They last between
two and three years in remotes and I can't tell you in the wall clock as
it's already gone for three years, longer than an alkaline cell would have.
--
Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)

 

[~misfit~]

Once upon a time on usenet Phil Allison wrote:

~misfit~ wrote:

Phil Allison wrote:
Gordon Levi wrote:

Some of my gadgets, notably a shaver and a TV remote, seem to work
better with alkaline rather than NiMh batteries. I have a weather
station that instructs me not to use "rechargeable" batteries.


** NiMH cells have a lower terminal voltage and high self discharge
rates - making them unsuitable for applications that do not require
high current or where a long time span between replacement is
important, like a wall clock.

Not completely true about high self discharge rates. There is an
increasing amount of 'LSD' NiMH cells. Eneloop started the trend but
I've seen at least five other major manufacturers have followed
suit. (I have some Varta and Panasonic LSDs along with a heap of
Eneloops.) I use them in everything from remotes and wall clocks to
LED flashlights and my camera. They last between two and three years
in remotes and I can't tell you in the wall clock as it's already
gone for three years, longer than an alkaline cell would have.


** Alkaline AA and AAA cells still have more energy capacity AND much
slower self discharge than Eneloops for about 1/4 the price.

For flashlights and cameras - use Eneloops, but for wall clocks or TV
remotes it's nuts.

You call it nuts I call it principle. I refuse to use a single-use cell
where I can use a rechargeable. Not all priorities have to be about money.
--
Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)

 

[Phil Allison]

~misfit~ wrote:

Phil Allison wrote:

** Alkaline AA and AAA cells still have more energy capacity AND much
slower self discharge than Eneloops for about 1/4 the price.

For flashlights and cameras - use Eneloops, but for wall clocks or TV
remotes it's nuts.


You call it nuts I call it principle. I refuse to use a single-use cell
where I can use a rechargeable. Not all priorities have to be about money.

** Well OK then.

But my wall clock and wireless door bell will not work long or at all if I use NiMH cells - the terminal voltage is too low.



..... Phil

 

[~misfit~]

Once upon a time on usenet Phil Allison wrote:

~misfit~ wrote:

Phil Allison wrote:

** Alkaline AA and AAA cells still have more energy capacity AND
much slower self discharge than Eneloops for about 1/4 the price.

For flashlights and cameras - use Eneloops, but for wall clocks or
TV remotes it's nuts.

You call it nuts I call it principle. I refuse to use a single-use
cell where I can use a rechargeable. Not all priorities have to be
about money.

** Well OK then.

But my wall clock and wireless door bell will not work long or at all
if I use NiMH cells - the terminal voltage is too low.

My clock's fine but alas, the wireless doorbell that I bought from Jaycar
simply won't work with NiMH cells (and stops working when alkalines are only
half-used). It's the only device that I use which doesn't take rechargable
cells.
--
Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)