15 minute battery chargers

[EOS Man]

I don't use my flash often, maybe 3-4 times a month usually and there are times where the batteries just run down after no use and I forget to charge them. This morning I picked up my flash, put the batteries in and the recharge time for full power took 16 seconds :lol: ! I may consider picking up one of those Sony 15 minute battery chargers seeing the number of things using AAs but do they really work or just a gimmick? It just seems kinda impossible that a normal charger's sit-for-7-hours time can be shortened to 15 minutes using one of those!

[liza]

They don't hold a charge as long. I've had better luck using Energizer 2500mah with the 8 hour chargers.

[Headcase650]

I have the 15 minute energizer charger and 4 sets of 4 2500mAh AA's. been using them for 2 years with out problems. nmh batteries self depleat, so if they sit for a few weeks you need to top them off befor using them in your flash. The 15 minute chargers get pretty warm but give them a few minutes for the fan to cool them off. Dead batteries, on the charger for 20 minutes, back into flash and I can get 120 full blast flashes befor the recycle time starts to slow.

[DocFrankenstein]

I wouldn't use fast charging unless I absollutely needed it. It kills the batteries.

My 8 hour chargers work much better and the batteries stay at ambient.

[Samgoit]

The 15 minute charger is a gimmick IMO. Read this thread through the second page:

http://photography-on-the.net/forum/showthread.php?t=310631

[Rumjungle]

If you use the flash very rarely, why not just use alkalines? They're cheap and have a long shelf life. Sounds perfect for you. Otherwise, try the Sanyo Enelope cells. They are rechargeable and have a lower rate of self-discharge than nicad or nickel metal hydride.

[BottomBracket]

You'd be better off with a smart battery charger such as the La Crosse Technology BC-900. With it you can not only charge your batteries (with different currents, depend on how fast you want it), you can also discharge it, test it (weed out the dead batteries) and refresh your batteries. It has an individual LCD readout for each battery - each battery is discretely monitored. If you have lots of NiMH batteries that you use regularly, this would be a great investment.

[cdifoto]

I have pretty good experience with the Duracell 1 Hour Charger that I got as a set with 4 AA batteries awhile back. None of my batteries have been deemed "shot" thus far, and I've had most sets for at least 6 months.

I wouldn't do a 15 minute charger though.

As far as what Pio said about weeding out the baddies - I number mine in sets of 4 with a Sharpie when I purchase them, and because of that I can easily use them in sets of 4 and charge them in sets of 4. When they go bad, they get trashed as a set of 4. No checking of individual batteries needed. :)

[EOS Man]

I have a set of 4 Kodak 2500mah AA's which charge in a regular 6-hour Sony charger yet the batteries seem warm-ish (kinda hot to hold) after a charge. Is this normal for a regular charger?

And correction: by saying I use my flash 3-4 times a month, I meant using it a lot till I recharge them after each shoot. So yeah, the batteries are recharged about every week or so.

[Curtis N]

They don't hold a charge as long.
It kills the batteries.I sure would like to see some credible documentation to go along with statements like that, or at least some personal anecdotes to back them up. There is so much misinformation, misunderstanding and myth about rechargeable batteries that the last thing I would believe is unsupported statements like this on a photography forum.

The following is from personal experience using NiMH batteries for seven years. I have had three chargers for NiMH AAs. The two that still work are both Energizer chargers. One is an overnight charger and one is a 15 minute charger.

The batteries come out of the 15 minute charger cooler than the overnight charger. There's a simple reason for this: It has a cooling fan!

I have six flash units and at least eight sets of batteries, some of which are seven years old. I use them a lot in my redneck "portable studio" setups. I have yet to experience a battery failure, or even a noticeable loss of battery capacity.

Does a 15 minute charger shorten a battery's life? I honestly don't know. But I have been using such a charger almost exclusively for 2 years now, and the convenience is sure worth it to me.

[cdifoto]

I use them a lot in my redneck "portable studio" setups.

You're not a redneck. You're a farmboy. :)

[1kerry]

I love my 15 min energizer charger alot!

[DocFrankenstein]

I sure would like to see some credible documentation to go along with statements like that, or at least some personal anecdotes to back them up.
I'd like to see world peace.

You can put your batteries in liquid nitrogen and "charge them completely" in 30 seconds for all I care.

Asking for "proof" on a forum is unproductive. This isn't an scientific journal.

[poloman]

I have a quick charger and while the elevated temp may shorten the batteries life a bit, so what? The batteries aren't that expensive and It's nice to be able to do it quickly. Something to be said for planning ahead though. I always prepare two fresh sets before a shoot. Then I'm sure.

[Headcase650]

Thanks, Curtis, Kerry and Poloman. It seems like every time a recommend the 15 minute charger, 20 people kick me in the nuts. I have a total of 8 sets of 4 AA's, but 4 of the sets are two years old and they work just as well as the ones Ive had for 6 months and they all get a good amount of use. It just seems to many people preach as to what you should or shouldnt do and they have no or incompleat experience with the subject matter.

[Samgoit]

Headcase650,

Your nuts and my nuts both are sacred to me. ;)

I am simply stating that the charger destroyed my batteries. I have no proof but my word and the readings I took with a multimeter. The Le Crosse charger drastically extended the usable time of my batteries. That is, they made my batteries usable.

I suspect that there is variability in the 15 minute chargers and some may be charging at greater currents, and that may be why people are getting different results?

It seems that some of us are getting very high battery temperatures while charging. That is not good (refer to the site you linked in the other thread).

I am not doubting you claims, but I am sure of mine.

[UnlnvlslblE]

It won't answer all the questions but its definitely a good read if you really want to get nitty-gritty about batteries. Check out http://batteryuniversity.com/. I followed some of their principals with my cell phone battery (charging before it is fully drained every night) and its lasted more than my previous batteries. I used to think it was good to do a full discharge and recharge often, but apparently its better to only do a complete discharge about once a month. I also applied their battery conditioning techniques and it really seemed to extend the life of the batteries. Give it a once over and you won't be disappointed.

[Curtis N]

I followed some of their principals with my cell phone battery (charging before it is fully drained every night) and its lasted more than my previous batteries. I used to think it was good to do a full discharge and recharge often, but apparently its better to only do a complete discharge about once a month.I will check out that link when I get a chance, but this generalization is part of the problem. Cell phone batteries are Lithium batteries. A completely different animal from NiMH, and they are very different from the NiCd batteries of yesteryear. You can't apply the same usage/recharging guidelines to completely different chemistry.

[UnlnvlslblE]

I will check out that link when I get a chance, but this generalization is part of the problem. Cell phone batteries are Lithium batteries. A completely different animal from NiMH, and they are very different from the NiCd batteries of yesteryear. You can't apply the same usage/recharging guidelines to completely different chemistry.


Yes I understand they are completely different. I was just trying to illustrate the usefulness of giving this a good read. All of what I said applies only to Li-Ion batteries. Though there are some similarities between Li-Ion and NiMH they are entirely a different breed.

If you do happen to check out the page one of the most useful sections is the charging table. It gives a great overview of how to treat, condition and charge different types of batteries.

[BottomBracket]

Whoah, nobody's kicking anyone in the nuts here, just sharing experiences. Truth be told, a 15 minute charger does work and if you are pressed for time it is a godsend. I do have an Energizer fast charger but I don't think it charges in 15 minutes though, more like an hour. I used it before I opted for the La Crosse BC-900.

When I got the La Crosse charger, I immediately tested all of my 24 NiMH rechargeables. Most were performing but at an mAh level lower than optimum. Three were nearly dead. I ran them all through the Refresh mode, which discharges the batteries completely and brings them up to their optimum mAh levels. 21 were optimized but the 3 remained dead. These 3 were disposed. And I have been using them in rotation with the other batteries!

That's the nice thing about this charger, it gives you quantitative analysis of each battery - it identifies which ones are performing well, which ones can be refreshed and brought up to speed, and which ones are dead. It is relatively cheap when it is on sale at Amazon, around $30 with free shipping, and it comes with a set of 4 AA and 4 AAA NiMH batteries. It is a good deal for what it does.

I still bring my fast charger when I travel. Otherwise, I use the BC-900 at home to charge my batteries. No nut kicking at all.

[Rudy M.]

Good site with lots of battery information.

http://en.wikipedia.org/wiki/Nickel_metal_hydride_battery

Some really good basic info that recommends over night charging at the rate of C/10 (capacity /10 = max charging rate in mAh) So if your batteries are 2400 mAh cells, cahrge them at no more than 240mAh rate for 10 hours, plus an hour or so of trickle to top off, but no more than 15 hours past full charge to avoid venting.

I only fast charge at 1000mAh with a Maha smart charger that charges and monitors each cell individually when I need batteries fast, otherwise I trickle charge batteries on smart chargers at C/10 rates or less. I have some NiMH batteries going on 8 years--remember when 1200 mAh NiMH batteries were all the rage? I still have 12 of them in service!

OTOH--why bother worrying about $10.00 in battery cost when compared to what you have spent on camera, lenses and flash!

[cosworth]

Ok ok. When I was in the caribbean I would completely disharge two complete sets of 4 NiMh batteries per day with my 580ex. I had a 15 minute charger (with fans) and I had a regular charger. I marked my batteries with tape to see if there was a difference in them dying at a certain point.

At no point could I determine a disernable difference between the two charging methods under my severe duty usage.

The largest varibale I could find was differences between batteries. Some of my regularly charged batteries were weak. Some of the 15 minute batteries were weak. I even had a dud in the regualrly charged set and had to replace it. It held a charge. But if it was in the 580 it would discharge quickly. A multimeter quicklyshowed it was the weak link.

Now the Energizers I was using (and still use) had different coloured tops on them. I took the tape off and stopped worrying. I did note that one of the regular charger sets had the light tops. I considered the light coloured set a potentially better set than any dark ones due to the 15 minute charger idea that they charge deeper, cleaner and safely.

Once back in Canada and not abusing my batteries nearly as much I went to go use a Nikon SB-80DX I had and lo and behold I had a burst battery gumming it up. It was a light top. It had spent most of it's life being charged in a regular charger.

I personally don't worry about what charger to use now. If I am just topping up I use the 15 minute, if putting some batteries to sleep after a long day they get the regular treatment.

Seriously, these batteries are like what, 15 bux at Wal-Mart? Do what you want to them and if they go south, chuck 'em. Arguing online about what charger to use on a $15 item is akin to comparing lens caps. Nearly pointless. Go shoot!

[Curtis N]

Seriously, these batteries are like what, 15 bux at Wal-Mart? Do what you want to them and if they go south, chuck 'em.That pretty much sums up my sentiments.

... and of course, "chuck 'em" means doing the environmentally responsible thing and turning them in to a recycling center. ;)

[BottomBracket]

Seriously, these batteries are like what, 15 bux at Wal-Mart? Do what you want to them and if they go south, chuck 'em. Arguing online about what charger to use on a $15 item is akin to comparing lens caps. Nearly pointless. Go shoot!

Who's arguing? We're merely discussing what the best charger is to use. If you would rather chuck away batteries that can be refreshed to their original capacity with a $30 charger, that's up to you. Otherwise, there's nothing wrong with trying to save a perfectly salvageable item if you can.

[cosworth]

You didn't read my post. I chuck batteries after they fail. Also don't forget NiMh AA doesn't respond well to refreshing.

[BottomBracket]

I read your post. Try the Refresh feature of the La Crosse BC-900 or a similar Maha model. You might be surprised with the number of batteries you can optimize.

[In2Photos]

I concur with Curtis and some others. I have both chargers and 12 batteries (8-2500, 4-2200). I use to solely use the 8 hour charger but it seemed like everytime I went to use the batteries they were dead and I had to wait 8 hours to use them. Since I got the 15 minute charger I ahve yet to use the 8 hour charger and they all seem to still work fine, day in and day out.

I'd like to see world peace.

You can put your batteries in liquid nitrogen and "charge them completely" in 30 seconds for all I care.

Asking for "proof" on a forum is unproductive. This isn't an scientific journal.
Then why do you do it? You have asked me several times.:rolleyes:

[BottomBracket]

Then why do you do it? You have asked me several times.:rolleyes:

Lol, Mike, so true, it's really hilarious:)

Back to chargers, I agree that this isn't much of an issue. They all work, and each one is a compromise between how fast you want your batteries charged and how much life you want to eke out of your batteries. I'm just the type who wants to maximize the use of things. I even re-use tape by rolling them back on pencils......

[wazmunstr]

i have rayovac 15 minute battery charger and the batteries that can only be used with it. 3 and half years later they still work holding a charge like the day i bought them.

i know for sure that 15 minute chargers dont work with all batteries, only the ones meant for it by the same name brand. so yes they do work, and great i might add.

[Linkzi]

i have rayovac 15 minute battery charger and the batteries that can only be used with it. 3 and half years later they still work holding a charge like the day i bought them.

i know for sure that 15 minute chargers dont work with all batteries, only the ones meant for it by the same name brand. so yes they do work, and great i might add.

I have the same system. I bought a bunch for back-up. When using my GPS time I flew, rechargeables were the way to go. I refreshed them after every use and can even charge them in my car. 15 minutes in a car, fully recharged is alot more versitile. After 5+ years, they are slowly starting to die so I discard them. I think I got my monies worth. Now you can only find the rayovacs on ebay.