Hybrio batteries?

ASAAR <caught.DeleteThis@22.com> wrote:
> On Fri, 29 Jun 2007 13:20:45 GMT, Thomas T. Veldhouse wrote:
>
>>> Because a significant percentage of alkaline battery energy is
>>> delivered at fairly low voltages, if a camera is designed to power
>>> off at relatively high voltages, lithium, NiCd and NiMH will do well
>>> and alkalines poorly.
>>>
>>
>> Actually, it is current related. The larger the current draw, the lower the
>> voltage maintained by the cell; alkalines do the poorest, followed by NiMH,
>> NiCd and finally Li (1.5V). I am not really sure where LiIon would fall in
>> that ranking, but I suspect between NiMH and NiCd. That is why devices that
>> draw high currents will indicate that a set of alkaline batteries are dead
>> when there is in fact significant capacity left; they draw a high current and
>> drop the voltage of the battery down below 1.0V.
>
> Of course the voltage drop is a function of the current. But I
> wasn't discussing that. The camera does not power off at a
> particular current draw. It powers off at its design voltage cutoff
> point.

Then we are in agreement. I was misled by your statement "Because a
significant percentage of alkaline battery energy is delivered at fairly low
voltages." I guess that is an odd way of putting it from my perspective.

>> Keep some standard high capacity 2700mAh NiMH batteries around
>> for those times when they would be consumed in a day or so of picture
>> taking and keep the Eneloop or Hybrid batteries in the camera for the
>> rest of the time.
>
> I would have done that a year or two ago, but I've since found
> that even when I shoot at a fairly high rate for several days
> straight both my Fuji and Canon cameras won't need a battery change,
> so I don't see a real need for standard 2,700mAh batteries because
> the lower Eneloop/Hybrid capacities are still good for a couple of
> days. So now I keep standard batteries in one camera and Eneloops
> in the other. Eventually I'll use only Eneloops in both cameras. I
> always have lots of alkalines and a few lithiums on hand for
> emergencies, even though I was never one of the Y2K fanatics.
>

I just keep the Eneloop and Hybrids around and swap them should I need
replacements. I mostly use them for my SB-600 and I don't take that many
shots with flash to begin with. My suggestion was mostly aimed at the OP who
might go on a photo binge and prefer the extra capacity for short bursts.

--
Thomas T. Veldhouse

Eat drink and be merry, for tomorrow they may make it illegal.
 >> Stay informed about: Hybrio batteries? 

Thomas T. Veldhouse wrote:
> ASAAR <caught RemoveThis @22.com> wrote:
>> Because a significant percentage of alkaline battery energy is
>> delivered at fairly low voltages, if a camera is designed to power
>> off at relatively high voltages, lithium, NiCd and NiMH will do well
>> and alkalines poorly.
>>
>
> Actually, it is current related. The larger the current draw, the lower the
> voltage maintained by the cell; alkalines do the poorest, followed by NiMH,
> NiCd and finally Li (1.5V). I am not really sure where LiIon would fall in
> that ranking, but I suspect between NiMH and NiCd. That is why devices that
> draw high currents will indicate that a set of alkaline batteries are dead
> when there is in fact significant capacity left; they draw a high current and
> drop the voltage of the battery down below 1.0V.
>
>> Well, just remember that when you finally install them, it's
>> probably wise to recharge them yearly when you change your smoke
>> alarm batteries, whether the Eneloops need charging or not. <g>
>> Actually, while the Eneloops will probably give you slightly fewer
>> shots per charge than you'll get from the lithium batteries, they
>> might produce slightly faster flash recycle times. You might want
>> to test this with a shot or two while the C743 is still using the
>> lithium batteries and then compare after the Eneloops are installed.
>>
>
> Keep some standard high capacity 2700mAh NiMH batteries around for those times
> when they would be consumed in a day or so of picture taking and keep the
> Eneloop or Hybrid batteries in the camera for the rest of the time.
>

I would point out that my old canon A40 stated Lithium batteries should
not be used. They never said why and your guess is as good as mine.
I don't see a similar caution with my A95 and haven't looked at other
canon (or any one else's models.)
Dave Cohen
 >> Stay informed about: Hybrio batteries? 

ASAAR wrote:
> On Fri, 29 Jun 2007 03:28:55 -0500, Ron Hunter wrote:
>
>> If a set of AA alkalines yield 1200 pictures on these cameras, one might
>> well install a set of lithium disposables and be fixed for the life of
>> the camera. Grin.
>
> We wish. Actually, that's not as true as it may seem.
> Lithium batteries don't really have a much greater energy capacity.
> Unlike alkalines, they don't waste much of it in internal heating.
> So the cameras that are old and have much greater current draws
> should get much better battery life from lithium batteries. The
> ones that are very efficient and get really great battery life from
> alkalines shouldn't do too much better with lithium batteries. But
> that's not always the case. The reason here would be cameras that
> weren't really designed for alkaline batteries in the first place.
> Because a significant percentage of alkaline battery energy is
> delivered at fairly low voltages, if a camera is designed to power
> off at relatively high voltages, lithium, NiCd and NiMH will do well
> and alkalines poorly.
>
> Contrasting examples are Nikon's SB-600 and SB-800 speedlights.
> The SB-600 is good for 200 flashes from four alkaline batteries and
> 400 flashes from lithium batteries. One would expect the higher
> power SB-800 to favor lithium batteries even more, but Nikon rates
> it at 130 flashes from four alkalines and 170 flashes from four
> lithium batteries. It could probably close the gap even more, but
> to get more than 130 flashes, the recycling time would probably get
> pretty lengthy. Nikon probably couldn't get more than 170 flashes
> from the lithiums because due to their higher voltage curve and
> steep drop at life-end, they were probably completely exhausted at
> the point of 170 flashes.
>
>
>> I installed two lithium disposables in my wife's Kodak C743 in December,
>> and I am still waiting for them to die before installing a shiny new set
>> of Eneloop batteries in it.
>
> Well, just remember that when you finally install them, it's
> probably wise to recharge them yearly when you change your smoke
> alarm batteries, whether the Eneloops need charging or not. <g>
> Actually, while the Eneloops will probably give you slightly fewer
> shots per charge than you'll get from the lithium batteries, they
> might produce slightly faster flash recycle times. You might want
> to test this with a shot or two while the C743 is still using the
> lithium batteries and then compare after the Eneloops are installed.
>

?? Seems that with lower internal resistance, and higher initial
voltage, the lithium disposables would recharge a flash faster. Am I
missing something?
The camera seems to have taken only about 250 pictures so far, so I
expect the batteries to last another few months, at least. Probably
should charge the Eneloops before I put them in so I can get a good feel
for how long they will last with a full charge. In either case, using
this camera is virtually free.
 >> Stay informed about: Hybrio batteries? 

On Sat, 30 Jun 2007 03:56:45 -0500, Ron Hunter wrote:

>> Well, just remember that when you finally install them, it's
>> probably wise to recharge them yearly when you change your smoke
>> alarm batteries, whether the Eneloops need charging or not. <g>
>> Actually, while the Eneloops will probably give you slightly fewer
>> shots per charge than you'll get from the lithium batteries, they
>> might produce slightly faster flash recycle times. You might want
>> to test this with a shot or two while the C743 is still using the
>> lithium batteries and then compare after the Eneloops are installed.
>
> ?? Seems that with lower internal resistance, and higher initial
> voltage, the lithium disposables would recharge a flash faster. Am I
> missing something?

Yep. The voltage may be higher, but it's very unlikely that
lithium batteries have a lower internal resistance. NiCd and NiMH
batteries have extremely low internal resistances. Checking data
sheets, all battery types have their internal resistances stated
with a high and a low value, probably representing the resistances
of fresh/fully charged vs. the resistance when depleted. The one
exception is lithium batteries, which don't include any internal
resistance values on the data sheets, but which give (for AA
batteries) a maximum sustained current of two amps and a maximum
intermittent current of three amps for a 20% duty cycle (two seconds
of current followed by 8 seconds of no current). From the given
internal resistances, both NiCd and NiMH AA batteries should be able
to deliver close to 10 amps when fully charged.

I've already posted what Nikon shows in its SB-800 manual for the
minimum recycle times of different battery types but here it is
again. The SB-800 normally uses four AA batteries, but can hold a
fifth AA cell to potentially increase the number of flashes and to
reduce the recycle times. For lithium batteries the recycle times
for 4 and 5 cells are the same, 7.5 seconds, probably due to the
lithium cell's current limit. For 1,000mAh NiCd batteries and
2,000mAh NiMH batteries the minimum recycle times are 4.0 seconds
for both when four AA cells are used. When five cells are used, the
NiCd recycle time drops to 3.5 seconds and the NiMH recycle time
drops to 2.9 seconds.



> The camera seems to have taken only about 250 pictures so far, so I
> expect the batteries to last another few months, at least. Probably
> should charge the Eneloops before I put them in so I can get a good feel
> for how long they will last with a full charge. In either case, using
> this camera is virtually free.

Or put the batteries (lithiums?) in an emergency flashlight and
start using the Eneloops now. In either case using the camera will
be free, but if you swap the batteries, in a few months the
flashlight's batteries will probably still be usable, increasing
your family's net worth by at least a few pennies.
 >> Stay informed about: Hybrio batteries?