Use Ni-CD’s for flash, NOT Ni-MH

[Stephen Reed]

I’ve lately seen some post here suggesting NiMH over NiCD batteries for flash. This is not a very good suggestion.

NiCD batteries have a significant lower internal resistance than NiMH do and will GREATLY lessen the flash recharge time. This is why cordless power drills still use NiCD’s, not NiMH’s. In electric RC car racing we ONLY use NiCDs.

The ONLY advantage the NiMH has over NiCD is capacity, but frankly I much prefer a quicker recharge rate from shot-to-shot.

I performed a test among three fully charged batteries to validate my point.

All test were repeated 20 times per battery type on a 420EX flash and averaged the results of time to refresh.. I also noted if the repeated draw on the battery changed its performance.

Sanyo NiCD** 3.53 sec (performance same over repeated firing.

Energizer 1850mah (Sanyo) NiMH** 6.20 sec (battery heated up degrading performance)
Energizer Lithium** 4.35 sec (performance consistent)
Energizer Alkaline** 4.07 sec (greatly fades over repeated firing)

Many have a false understanding of NiMH vs NiCD batteries. Marketing has consumers thinking NiMH has huge advantages over NiCD. In terms of capacity this is somewhat true, BUT higher capacity batteries also have a higher fail rate. People are also sucked in to the “memory” issue of NiCDs. The memory issue happens because the chemicals in the battery start to crystallize when stuck in one state for too long. The thing to avoid is leaving the battery on a charger routinely after charged and to not continually “top-off” the battery. Oh….did I mention that NiMH batteries suffer the same issues?

The message here is to dispel a myth. If you want significantly faster recharge(recycle) times on your external flash, then NiCD batteries are by far the best way to go.

NiMH are much safer for the environment, and this may justify some peoples use of them.

--
Stephen Reed



http://www.pbase.com/domotang

 

[edtang]

I think that NiCADs have better cold weather performance, no?

 

[Alesandro Allegre Marco Dos]

...is that it's easy to just adopt NiMH's for all your AA needs. I have like 40-50 of these things. If there aren't as frisky as you like then you can pop in some new ones or attach a CP-E2. You can fill flash 8 fps for a second or so at 1/128th power or whatever and "your" "proberbly" looking at about a half second recharge time with normal use. Maybe change the batteries once on a night when you're taking 300 flash shots. Good enough for me.

I'd be afraid to test my flash 20 times in succession at full power.

I’ve lately seen some post here suggesting NiMH over NiCD batteries
for flash. This is not a very good suggestion.
NiCD batteries have a significant lower internal resistance than
NiMH do and will GREATLY lessen the flash recharge time. This is
why cordless power drills still use NiCD’s, not NiMH’s. In electric
RC car racing we ONLY use NiCDs.
The ONLY advantage the NiMH has over NiCD is capacity, but frankly
I much prefer a quicker recharge rate from shot-to-shot.

I performed a test among three fully charged batteries to validate
my point.
All test were repeated 20 times per battery type on a 420EX flash
and averaged the results of time to refresh.. I also noted if the
repeated draw on the battery changed its performance.

Sanyo NiCD** 3.53 sec (performance same over repeated firing.
Energizer 1850mah (Sanyo) NiMH** 6.20 sec (battery heated up
degrading performance)
Energizer Lithium** 4.35 sec (performance consistent)
Energizer Alkaline** 4.07 sec (greatly fades over repeated firing)

Many have a false understanding of NiMH vs NiCD batteries.
Marketing has consumers thinking NiMH has huge advantages over
NiCD. In terms of capacity this is somewhat true, BUT higher
capacity batteries also have a higher fail rate. People are also
sucked in to the “memory” issue of NiCDs. The memory issue happens
because the chemicals in the battery start to crystallize when
stuck in one state for too long. The thing to avoid is leaving the
battery on a charger routinely after charged and to not continually
“top-off” the battery. Oh….did I mention that NiMH batteries suffer
the same issues?

The message here is to dispel a myth. If you want significantly
faster recharge(recycle) times on your external flash, then NiCD
batteries are by far the best way to go.

NiMH are much safer for the environment, and this may justify some
peoples use of them.

--
Stephen Reed



http://www.pbase.com/domotang

 

[Brian62986]

Stephen,

NiMH batteries have been used heavily in electric RC racecars for many years now and are preferred due to their capacity (you can run a lot hotter motor with them). Look at any RC car magazine - the best batteries are NiMH, only the "play" batteries (i.e., inexpensive packs) are NiCD.

You are correct in stating the the ESR of a NiMH cell is higher than that of a NiCD, though.

Maybe I used really cheap alkalines, but switching to NiMH for my flash really cut down the recycle time. I did not have an overheating issue either. I'm using 2300mAH Mahas.

Brian

 

[Stephen Reed]

I think that NiCADs have better cold weather performance, no?

NiCds do better in cold and hot weather.

--
Stephen Reed



http://www.pbase.com/domotang

 

[TrapperJ]

As Alesandro points out, you can attach a CP-E2 or the new CP-E3. When I use the CP-E2 power pack with the 550EX, I typically get recycle times of 1-2 seconds using NiMHs. I think if you populate the power packs with NiCds there isn't going to be a significant improvement...I mean you are really at the limits of the flash/powerpack combo capabilities. So, that being the case, I use the NiMHs and get a marked increase in the number of flashes I get.

...is that it's easy to just adopt NiMH's for all your AA needs. I
have like 40-50 of these things. If there aren't as frisky as you
like then you can pop in some new ones or attach a CP-E2. You can
fill flash 8 fps for a second or so at 1/128th power or whatever
and "your" "proberbly" looking at about a half second recharge time
with normal use. Maybe change the batteries once on a night when
you're taking 300 flash shots. Good enough for me.

--
James

 

[Stephen Reed]

Alkaline batteries do better in low drain applications. NiMH is much better for flash units than Alkalines. NiCD do better than NiMH for recycle time.

Maybe I used really cheap alkalines, but switching to NiMH for my
flash really cut down the recycle time. I did not have an
overheating issue either. I'm using 2300mAH Mahas.

Brian

--
Stephen Reed



http://www.pbase.com/domotang

 

[Stephen Reed]

I just tested the performance difference between the NiCD and NiMH in my CP-E3 battery pack. The performance was not measurable with a stopwatch. The flash circuitry is the limiting factor here.

As Alesandro points out, you can attach a CP-E2 or the new CP-E3.
When I use the CP-E2 power pack with the 550EX, I typically get
recycle times of 1-2 seconds using NiMHs. I think if you populate
the power packs with NiCds there isn't going to be a significant
improvement...I mean you are really at the limits of the
flash/powerpack combo capabilities. So, that being the case, I use
the NiMHs and get a marked increase in the number of flashes I get.

--
Stephen Reed



http://www.pbase.com/domotang

 

[Divo]

I seem to recall reading that NiMh batteries are not recommended for use with Canon flashes. Any truth to that?

Maybe I used really cheap alkalines, but switching to NiMH for my
flash really cut down the recycle time. I did not have an
overheating issue either. I'm using 2300mAH Mahas.

Brian

--
Stephen Reed



http://www.pbase.com/domotang

 

[Todd Corzett]

NiMH batteries have been used heavily in electric RC racecars for
many years now and are preferred due to their capacity (you can run
a lot hotter motor with them).

Yup! I've been out of the RC world for about 3 years (switched to photography), but when I raced (semi-pro) NiMH were getting more and more popular for modified classes of racing where battery life vs. motor wind ("hotness") was still an issue to make the 5-7min race lengths.

However, as Stephen said, the rate of discharge is greater (lower internal resistance) for NiCDs. So those who were running stock motors (like me) were using NiCDs over NiMH. We actually used the memory feature of the bateries to get them to dump the power as fast as possible (who needs extra life after the 5min race is over). Back-in-the-day when my dad raced (25-years ago or so) battery science was actually what was winning the races (like Modified racing 'today') as he/she who had the best batteries had a serious advantage over the other drivers.

Now as for photography... Yes, NiCDs will recycle faster than NiMH...

BUT for most people the recycle rate of a flash is less of an isue than the number of photos that can be taken. Also the lack of memory (real or not... this is another discussion all together) is great for those who don't want to keep binders with the charge data from their batteries (like I did with my RC packs... yes, I'm a big nerd). For the average user the ability to charge, use, and (quickly) re-charge is what is needed (most people don't like to discharge, recycle, trickle-charge, etc.).

If you're really concerned with getting the max-refresh rate for your flash go get an external battery like a Quantum Turbo. It's funny to read the manual and find out that the battery can damage the flash because it recycles fast enough to cause excessive heat... you actually have to STOP shooting because the FLASH gets too hot (after around 30 flashes). My Turbo 2x2 (NiMH by the way) has no problem keeing up with 3-4fps at full flash power.

-Todd...

--
-----
Unit One Studios
http://www.unitonestudios.com

 

[PhotoTom]

The EX-550 manual, page 10 states "Speedlite 550EX requires one of the following two types of batteries:
a - Size AA alkaline batteries
b - Size AA nickel-hydride batteries"

It doesn't seem to say that you can or cannot use NiCD batteries, but they aren't listed as one of the types that you SHOULD use.

Maybe I used really cheap alkalines, but switching to NiMH for my
flash really cut down the recycle time. I did not have an
overheating issue either. I'm using 2300mAH Mahas.

Brian

--
Stephen Reed



http://www.pbase.com/domotang

--
Tom

 

[Todd Corzett]

The EX-550 manual, page 10 states "Speedlite 550EX requires one of
the following two types of batteries:
a - Size AA alkaline batteries
b - Size AA nickel-hydride batteries"

It doesn't seem to say that you can or cannot use NiCD batteries,
but they aren't listed as one of the types that you SHOULD use.

Not to say the that is wrong (as I don't have my manual infront of me), but on the Canon webpage for the specifications for the 550EX ( http://consumer.usa.canon.com/ir/controller?act=ModelTechSpecsAct&fcategoryid=141&modelid=7270 ) lists under the Power Source "Size-AA alkaline LR6 batteries (6 V) x 4; Size-AA Nicad KR 15/51 batteries x 4 Size-AA Lithium FR6 batteries (6 V) x 4".

So it sounds to me like NiCDs are good to go.

-Todd...

--
-----
Unit One Studios
http://www.unitonestudios.com

 

[PhotoTom]

....Based on what the web site says. Actually, I can't see any reason why the NiCD batteries shouldn't be OK, except for the possibility that the slightly lower voltage might affect the electronics.

Its weird - I have the manual saying one thing and Canon's web page saying another.

The EX-550 manual, page 10 states "Speedlite 550EX requires one of
the following two types of batteries:
a - Size AA alkaline batteries
b - Size AA nickel-hydride batteries"

It doesn't seem to say that you can or cannot use NiCD batteries,
but they aren't listed as one of the types that you SHOULD use.

Not to say the that is wrong (as I don't have my manual infront of
me), but on the Canon webpage for the specifications for the 550EX

( http://consumer.usa.canon.com/ir/controller?act=ModelTechSpecsAct&fcategoryid=141&modelid=7270 ) lists under the Power Source "Size-AA alkaline LR6 batteries (6 V) x 4; Size-AA Nicad KR 15/51 batteries x 4 Size-AA Lithium FR6 batteries (6 V) x 4".

So it sounds to me like NiCDs are good to go.

-Todd...

--
-----
Unit One Studios
http://www.unitonestudios.com
-----

--
Tom

 

[Robert Scultz]

nicads, have a memory effect, and need discharge for full recharge,
and depleate, loose more power, due storage, if I got it right,...

for most people, the nimh will be more consistent over the live and usage of the batteries in conjunction with a flash,...
as pointed out, the difference dissapears, when used with a CP battery pack,...

best choice, is a high voltage batterypack, where the flash is charged with high voltage,
that reduces greatly the inefficient charge circuit in flash.

there are couple of batterypacks that have the choice, and Metz flashes support that (pro)... high voltage , extra cable,....

for the cheep (expensive on the long run) photographer,... you would just use lithium batteries, for the time you need a portable flash.

for the big boys,... the use flash packs, with batteries the size of car/truck batteries,...

where you need an assistant with a wheelbarrel, to move it around,.... and recharge cycle , is usually not an issue.

cheers, Robert Schultz

 

[Stephen Reed]

true NiCDs do have more pronounced memory effect,.
But NiMH leak much more power than NiCDs when stored.

And you are right, Flash pcks ROCK!!! The problem is the 420EX can't use a power pack, so the NiCD may be a good alternative.

nicads, have a memory effect, and need discharge for full recharge,
and depleate, loose more power, due storage, if I got it right,...
for most people, the nimh will be more consistent over the live and
usage of the batteries in conjunction with a flash,...
as pointed out, the difference dissapears, when used with a CP
battery pack,...
best choice, is a high voltage batterypack, where the flash is
charged with high voltage,
that reduces greatly the inefficient charge circuit in flash.
there are couple of batterypacks that have the choice, and Metz
flashes support that (pro)... high voltage , extra cable,....
for the cheep (expensive on the long run) photographer,... you
would just use lithium batteries, for the time you need a portable
flash.
for the big boys,... the use flash packs, with batteries the size
of car/truck batteries,...
where you need an assistant with a wheelbarrel, to move it
around,.... and recharge cycle , is usually not an issue.

cheers, Robert Schultz

--
Stephen Reed



http://www.pbase.com/domotang

 

[joe pasint]

Stephen, have you strolled down the isles of your local Home Depot lately? Power tools, including some of the big names like Milwaukee are already selling power tools with NiMH batteries. A great thing if you ask me as the memory affect of NiCds is a bad deal all the way around. The link below is a great source of knowledge for batteries.

Take care.

Joe

http://www.batteryuniversity.com/partone.htm

 

[Stephen Reed]

There are many reasons I'm glad the NiMH battery is replacing the NiCD . . . especially in mass consumer products. The biggest concern for me was how toxic the NiCD is, so being no longer mainstream is welcome.

But in applications that are more demanding on the battery in terms of high drain, the NiCD is more capable of delivering because of its lower impedance. This may be a solution for those more concerned about their flash recycle time than the capacity.
The drill I just bought, the DeWALT HD XRP 18V HammerDrill uses NiCDs.
Great drill BTW...

Stephen, have you strolled down the isles of your local Home Depot
lately? Power tools, including some of the big names like Milwaukee
are already selling power tools with NiMH batteries. A great thing
if you ask me as the memory affect of NiCds is a bad deal all the
way around. The link below is a great source of knowledge for
batteries.

--
Stephen Reed



http://www.pbase.com/domotang

 

[joe pasint]

Hope you have better luck with yours than I did mine. Sucker was over $200.00 I think. 4 years of very light usage and the battery always tries to fall out and the chuck is weak in the you know what. Hopefully for you, they changed the battery clips.

Joe

 

[Stephen Reed]

I heard the new ones are better.

I have an older (1 year old) 14.4volt XRP drill that has been through hell and back. I used it to grind ALL the rust off an old 1978 VW convertible. I really abused the thing. It still works great.
I just bought this one because I need the hammer.

Hope you have better luck with yours than I did mine. Sucker was
over $200.00 I think. 4 years of very light usage and the battery
always tries to fall out and the chuck is weak in the you know
what. Hopefully for you, they changed the battery clips.

Joe

--
Stephen Reed



http://www.pbase.com/domotang