Batteries

In article , A
Moose in Love wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull knife goes
through cheese. So yesterday, I purchased 4 rechargeable duracell batteries
with a charger. Now, the question is: will these batts hold a charge longer
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.
They'll also have a far faster self-discharge rate when not in use. If
you're a heavy user and want to save money, get two sets of
rechargables and use one while the other is charging. If you don't
shoot much but want the camera always ready to use, get disposable
lithium AA's.

In article , Scott Schuckert
wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull knife goes
through cheese. So yesterday, I purchased 4 rechargeable duracell batteries
with a charger. Now, the question is: will these batts hold a charge
longer
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.
alkalines can't handle the current demands a camera requires. however,
once they cease being able to power the camera, they can still be used
for low demand items such as a flashlight or radio.

They'll also have a far faster self-discharge rate when not in use.

eneloops have a very low self-discharge rate, or just charge them
before use. not a big deal.

If you're a heavy user and want to save money, get two sets of
rechargables and use one while the other is charging.

it depends on what you consider heavy and how many photos you can get
from a charge (and how soon you'll be able to recharge it).

If you don't
shoot much but want the camera always ready to use, get disposable
lithium AA's.

only if you shoot very little. lithiums are good for a backup though
since they last forever.

for cameras that take aa batteries, rechargeables are definitely the
way to go.

On 01/05/2014 14:09, nospam wrote:
In article , Scott Schuckert
wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull knife goes
through cheese. So yesterday, I purchased 4 rechargeable duracell batteries
with a charger. Now, the question is: will these batts hold a charge
longer
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.

Rubbish. Single use fresh alkalines have both a higher unloaded terminal
voltage and a significantly higher Ah capacity to discharge. The only
problem is they are one time usage and so more expensive.

The unloaded terminal voltage of NiMH is sufficiently low that they will
fail the voltage margin test on lots of cameras long before they are
anything like fully discharged. Usually they fail for low voltage when
the camera decides it need to charge its flash.

alkalines can't handle the current demands a camera requires. however,
once they cease being able to power the camera, they can still be used
for low demand items such as a flashlight or radio.

Yes they can. A standard AA cell can source over 10A into a dead short
(this is defnitely not recommended).

They'll also have a far faster self-discharge rate when not in use.

eneloops have a very low self-discharge rate, or just charge them
before use. not a big deal.

Any of the low self discharge types are OK for this usage.

If you're a heavy user and want to save money, get two sets of
rechargables and use one while the other is charging.

it depends on what you consider heavy and how many photos you can get
from a charge (and how soon you'll be able to recharge it).

I use rechargeables most of the time but I still carry a set of classic
alkalines in the bag in case they decide to play up.

--
Regards,
Martin Brown

In article , Martin Brown
wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull knife
goes
through cheese. So yesterday, I purchased 4 rechargeable duracell
batteries
with a charger. Now, the question is: will these batts hold a charge
longer
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.

Rubbish. Single use fresh alkalines have both a higher unloaded terminal
voltage and a significantly higher Ah capacity to discharge. The only
problem is they are one time usage and so more expensive.

nothing rubbish about it. alkalines do not last very long in cameras.
this is well known.

The unloaded terminal voltage of NiMH is sufficiently low that they will
fail the voltage margin test on lots of cameras long before they are
anything like fully discharged. Usually they fail for low voltage when
the camera decides it need to charge its flash.

nonsense. nicad/nimh batteries have been commonplace for a couple of
decades and anything that doesn't work properly with them is defective.

alkalines can't handle the current demands a camera requires. however,
once they cease being able to power the camera, they can still be used
for low demand items such as a flashlight or radio.

Yes they can. A standard AA cell can source over 10A into a dead short
(this is defnitely not recommended).

not for very long it can't. the problem is not that it can't supply
high current but that it stops being able to do that really quickly.

this is the same reason why flash recycle times are much shorter with
nimh (or previously, nicad).

They'll also have a far faster self-discharge rate when not in use.

eneloops have a very low self-discharge rate, or just charge them
before use. not a big deal.

Any of the low self discharge types are OK for this usage.

yes, as are normal rechargeables. unless they sit unused for a while,
the low self-discharge is not a big deal.

If you're a heavy user and want to save money, get two sets of
rechargables and use one while the other is charging.

it depends on what you consider heavy and how many photos you can get
from a charge (and how soon you'll be able to recharge it).

I use rechargeables most of the time but I still carry a set of classic
alkalines in the bag in case they decide to play up.

much better to get a set of lithiums because shelf life is over 10
years. buy a set and don't worry about it.

In article , nospam
wrote:

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.
alkalines can't handle the current demands a camera requires. however,
once they cease being able to power the camera, they can still be used
for low demand items such as a flashlight or radio.

You really are a contrary little thing, aren't you? Note "depending on
exact batteries purchased." There are low capacity rechargables, and
variations on alkaline performance. For the Duracell the OP most likely
meant, that's perhaps 2000 mAh; many alkalines exceed that.

In article , Scott Schuckert
wrote:

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.
alkalines can't handle the current demands a camera requires. however,
once they cease being able to power the camera, they can still be used
for low demand items such as a flashlight or radio.

You really are a contrary little thing, aren't you?

not at all. unlike you, i understand battery technology.

Note "depending on
exact batteries purchased."

obviously. i didn't say otherwise.

not only does it depend on the batteries purchased, but it also depends
on the device with which the batteries are used.

for cameras, nimh is almost always going to last longer, whereas for a
flashlight, alkaline is a better choice.

There are low capacity rechargables, and
variations on alkaline performance. For the Duracell the OP most likely
meant, that's perhaps 2000 mAh; many alkalines exceed that.

not under load, they can't, and a digital camera is a fairly big load,
which is why nimh lasts longer, even if its mah is lower. it's also why
a flash recycles faster with nimh.

On 2014.05.01, 09:43 , Martin Brown wrote:
On 01/05/2014 14:09, nospam wrote:
In article , Scott Schuckert
wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull
knife goes
through cheese. So yesterday, I purchased 4 rechargeable duracell
batteries
with a charger. Now, the question is: will these batts hold a charge
longer
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.

Rubbish. Single use fresh alkalines have both a higher unloaded terminal
voltage and a significantly higher Ah capacity to discharge. The only
problem is they are one time usage and so more expensive.

No. NiMH (or NiCd) have very high current rates (despite a lower
nominal voltage) than alkaline.

This is easily demonstrated on an accessory flash where with NiMH the
recycle time from a full power flash pulse is about 2.5 seconds but with
brand new alkaline it is 5 or 6 seconds. (guide number 56 - a "big"
flash). That shows the alkaline can't deliver the current even if their
open voltage is higher.

I carry a pack of alkalines as backup, but my NiMH's always get me
through my sessions. My later NiMH's are eneloop - low (near 0) self
discharge.

I haven't used AA's as main batteries in a camera - so I won't speak to
that. Offhand, except for flash use, I'd expect alkaline to have more
endurance. On the other hand NiMH's have gotten pretty energy dense in
the last 10 years. And with Eneloop's the self discharge is very low
(zero for practical purposes).

I do use alkaline in other devices with a low current demand, such as
GPS recorder on a long hike. These definitely last longer than the
NiMH's I have.

Right battery for the job.

--
"Big data can reduce anything to a single number,
but you shouldn’t be fooled by the appearance of exactitude."
-Gary Marcus and Ernest Davis, NYT, 2014.04.07

On 2014.05.01, 08:26 , Scott Schuckert wrote:
In article , A
Moose in Love wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull knife goes
through cheese. So yesterday, I purchased 4 rechargeable duracell batteries
with a charger. Now, the question is: will these batts hold a chargelonger
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.
They'll also have a far faster self-discharge rate when not in use.



Eneloop



- high capacity
- low self discharge
- high amperage (for attached flash)
- pretty high capacity (mine are 1500 mAh x 1.2V - there are higher
capacity versions)
- no brainer.

--
"Big data can reduce anything to a single number,
but you shouldn’t be fooled by the appearance of exactitude."
-Gary Marcus and Ernest Davis, NYT, 2014.04.07

On 01/05/2014 22:44, Alan Browne wrote:
On 2014.05.01, 09:43 , Martin Brown wrote:
On 01/05/2014 14:09, nospam wrote:
In article , Scott Schuckert
wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull
knife goes
through cheese. So yesterday, I purchased 4 rechargeable duracell
batteries
with a charger. Now, the question is: will these batts hold a charge
longer
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.

Rubbish. Single use fresh alkalines have both a higher unloaded terminal
voltage and a significantly higher Ah capacity to discharge. The only
problem is they are one time usage and so more expensive.

No. NiMH (or NiCd) have very high current rates (despite a lower
nominal voltage) than alkaline.

They have a lower internal resistance yes, but they also have a lower
unloaded terminal voltage and a higher energy density. It is the low
voltage that causes digital cameras logic to shut down prematurely
particularly once the thing tries to charge up its internal flash.

This is easily demonstrated on an accessory flash where with NiMH the
recycle time from a full power flash pulse is about 2.5 seconds but with
brand new alkaline it is 5 or 6 seconds. (guide number 56 - a "big"
flash). That shows the alkaline can't deliver the current even if their
open voltage is higher.

Alkaline don't deliver quite as high a current but only big flash guns
draw that sort of power when recharging and some cheap and nasty flash
guns can be destroyed by holding down the test flash button if you are
using rechargeables (NiCad or NiMH).

I carry a pack of alkalines as backup, but my NiMH's always get me
through my sessions. My later NiMH's are eneloop - low (near 0) self
discharge.

I haven't used AA's as main batteries in a camera - so I won't speak to
that. Offhand, except for flash use, I'd expect alkaline to have more
endurance. On the other hand NiMH's have gotten pretty energy dense in
the last 10 years. And with Eneloop's the self discharge is very low
(zero for practical purposes).

But in a camera the single use secondary cell wins for lifetime because
it takes much longer to fall below the threshold low voltage safety
value. Some very low current consumer appliances won't work from NiMH at
all but will work quite happily from "spent" alkalines.

I do use alkaline in other devices with a low current demand, such as
GPS recorder on a long hike. These definitely last longer than the
NiMH's I have.

Right battery for the job.

Indeed. But digital cameras no longer take 2-3 amps like the original
DC-120 used to do. Alkalines will supply more Ah than any rechargable.

They can't quite match the peak current but a humble AA cell will still
deliver over 10A into a dead short. Enough to make thin wires red hot
pretty quickly. They can explode if provoked this way too.

--
Regards,
Martin Brown

In article ,
says...

On 01/05/2014 22:44, Alan Browne wrote:
On 2014.05.01, 09:43 , Martin Brown wrote:
On 01/05/2014 14:09, nospam wrote:
In article , Scott Schuckert
wrote:

Man. My camera Canon A2000 goes through AA batteries like a dull
knife goes
through cheese. So yesterday, I purchased 4 rechargeable duracell
batteries
with a charger. Now, the question is: will these batts hold a charge
longer
than the other non rechargeable batts? I hope so.

It depends on the exact batteries purchased, but in many cases, the
rechargables won't last as long - per charge - as an alkaline battery.

nope. for a camera, nimh will almost always last much, much longer.

Rubbish. Single use fresh alkalines have both a higher unloaded terminal
voltage and a significantly higher Ah capacity to discharge. The only
problem is they are one time usage and so more expensive.

No. NiMH (or NiCd) have very high current rates (despite a lower
nominal voltage) than alkaline.

They have a lower internal resistance yes, but they also have a lower
unloaded terminal voltage and a higher energy density. It is the low
voltage that causes digital cameras logic to shut down prematurely
particularly once the thing tries to charge up its internal flash.

This is easily demonstrated on an accessory flash where with NiMH the
recycle time from a full power flash pulse is about 2.5 seconds but with
brand new alkaline it is 5 or 6 seconds. (guide number 56 - a "big"
flash). That shows the alkaline can't deliver the current even if their
open voltage is higher.

Alkaline don't deliver quite as high a current but only big flash guns
draw that sort of power when recharging and some cheap and nasty flash
guns can be destroyed by holding down the test flash button if you are
using rechargeables (NiCad or NiMH).

I carry a pack of alkalines as backup, but my NiMH's always get me
through my sessions. My later NiMH's are eneloop - low (near 0) self
discharge.

I haven't used AA's as main batteries in a camera - so I won't speak to
that. Offhand, except for flash use, I'd expect alkaline to have more
endurance. On the other hand NiMH's have gotten pretty energy dense in
the last 10 years. And with Eneloop's the self discharge is very low
(zero for practical purposes).

But in a camera the single use secondary cell wins for lifetime because
it takes much longer to fall below the threshold low voltage safety
value. Some very low current consumer appliances won't work from NiMH at
all but will work quite happily from "spent" alkalines.

This is only an issue for some antiquated model that isn't designed to
work with NiMH. The discharge curve on NiMH is flatter than for
alkaline so devices that can work at all on NiMH tend to run a lot
longer on it than they do on alkaline.

I do use alkaline in other devices with a low current demand, such as
GPS recorder on a long hike. These definitely last longer than the
NiMH's I have.

Right battery for the job.

Indeed. But digital cameras no longer take 2-3 amps like the original
DC-120 used to do. Alkalines will supply more Ah than any rechargable.

They can't quite match the peak current but a humble AA cell will still
deliver over 10A into a dead short. Enough to make thin wires red hot
pretty quickly. They can explode if provoked this way too.