AA Batteries for Camera Flashes

[Bearmann]

On another forum we were having a discussion of white Eneloops versus Eneloop XX versus Powerex 2700s', primarily for use in camera flashes like a Canon 580EX. Comparing the white Eneloops to the XX Eneloops, I said:


The XX batteries hold 75% of their charge after one year, or 0.75 x 2500 = 1850. I can't find the one year rate on the regular Eneloops, but I think it must be around 90% for the most recent models, or 0.90 x 2000 =1800. So for the first year, the XX will run longer, and after that the regular Eneloops will pull ahead. So if you want a battery that will last longer between re-charges, the XX batteries seem to be a good choice.

I was told that my logic was faulty. Is it?

What batteries would you recommend if a long shelf life is important?

What batteries would you recommend if you recharged them before every event?

I have looked at some of the Ragone plots, but I'm not very competent in reading them, so I'm hoping to be spoon fed in the thread ;)

 

[ChrisGarrett]

http://www.candlepowerforums.com/vb...ut-Eneloops-GP-ReCyKos-and-Imedions-it-s-done!

I did a one year test as noted above and with , my sample size of 4 new Eneloop Gen. 2s, they lost about 13% after that year.

XX/Pros yield less cycles, but about 20% more capacity, so if you'll be using them in a camera, for flash purposes, they might be the way to go.

~500 cycles is about one cycle a week for four and a half years.

This presumes that the XX/Pros have the same output with regards to current draw/push, as the regular Eneloop Gen.2s, 3s and 4s.

The XX/Pros do pretty well at 5A, but I don't know what your flash draws:

http://lygte-info.dk/review/batteries2012/Eneloop AA HR-3UWXB 2450mAh (Black) UK.html

Chris

 

[Bearmann]

Thanks the information, Chris. I don't know a lot about electrical stuff, so I though maybe my mathematical approach was in error. Reading this forum, it appears like the higher the mAh, the shorter the life of the battery (until it won't recharge). So the Powerex 2700's and the Eneloop XX batteries might both fall victim to this.

 

[alpg88]

What batteries would you recommend if a long shelf life is important?

lithium primarys.

 

[moldyoldy]

a different view of the use of cells in AA flashes for photography:

When I was active in sports/wedding photography, I was far more concerned about the runtime of the cells during use as well as the recharge time after a flash capacitor dump (usually bounced somehow). Candids were especially hard on the cells/recycle time since the ballrooms typically had low lighting. I charged all of my cells the day before and discharged several sets during the event coverage.

I learned to recycle all cells after a couple years. Had they dropped to 80%? of nominal capacity? No idea, I never tested them - no time - just recycled the cells. The basis for recycling at ~2 years was that I could easily perceive that the flash recharge time using those cells had increased unacceptably - worn out for all practical purposes. yes, I wanted fast recycling. Waiting for a flash to recycle was not nice.


Sometimes I even used an on-shoe and an off-shoe flash (both triggered identically, no slaving, but when the shutter was closing,not opening). Otherwise I/we had multiple Nikon 4xAA flashes as well as the big strobes with a battery over the shoulder.

 

[mcnair55]

I use normal Eneloop and carry 4 spares with me,never had a problem and to date never used the spares.

 

[ChrisGarrett]

Thanks the information, Chris. I don't know a lot about electrical stuff, so I though maybe my mathematical approach was in error. Reading this forum, it appears like the higher the mAh, the shorter the life of the battery (until it won't recharge). So the Powerex 2700's and the Eneloop XX batteries might both fall victim to this.

500 cycles is one cycle per week for 9.6 years, so two cycles a week for 4.8 years.

Personally, for casual use, most of us can live with 500 cycles, or even 400, before shelling out a few bucks for new batteries.

The issue for me is the quality of some of these hi-cap HSD batteries, like the PowerEx 2700s, my AccuPower 2900s and my Sanyo 2700s. Do we even get 200 cycles out of them before they crap out on us?

I've got some AccuPower 1200 AAAs that pumped up close to 1200mAh, but after almost two years of minor use, maybe 40 cycles at most, one quad is now down to 800ish mAh, so what's up with that?

If you need higher capacity and you don't mind <500 cycles, just stick with the Eneloop XX/Pros (or these new Duracell Ion Core Duraloop 2400s,) as their quality of manufacture is well regarded. Some of the other Chinese sourced hi-cap HSDs, who knows?

A lot of people here will give you a cost/benefit analysis showing you that you're actually better off with standard Eneloop 1500s, than you are when using the 500 cycle 2500mAh XX/Pros, but if you're that guy at the wedding snapping picks, you might prefer to have that extra 50 flashes, rather than carrying around extra sets of batteries and having to change them out at inopportune times, no?

We all need to be using the right tool for the job.

Chris

 

[Bearmann]

lithium primarys.

Oh, my carelessness. I meant to specify rechargable batteries.

......A lot of people here will give you a cost/benefit analysis showing you that you're actually better off with standard Eneloop 1500s, than you are when using the 500 cycle 2500mAh XX/Pros, but if you're that guy at the wedding snapping picks, you might prefer to have that extra 50 flashes, rather than carrying around extra sets of batteries and having to change them out at inopportune times, no?

We all need to be using the right tool for the job.

Chris

Yes, exactly!