Looking for rechargeable battery experts?

[Cavelightchris]

Ok so I wrote this article on rechargeable batteries, and I was hoping some of you battery experts could read it and tell me what you think:

http://louisville.caves.org/Batteries.html

Is any of it not true?

Is there any great information you think I should add to it?


I would like to thank SilverFox for all of his battery testing which made my graph possible. I did spend two hours resizing 4 of his graphs so that I could put 4 different batteries on one graph, but it was a learning experience anyhow.


Thanks,

Chris

 

[VidPro]

There are only two kinds of rechargeables that most highly experienced battery users recommend: Energizers . . .
whaaaa?
the energypster High-capacity batteries i would not recommend ever , lost some $150 bucks because of them.

here is what i would add, Many people have found that energizser 2500s, and the newer 2450s do not hold a charge after some cycles use and time, and generally suck very badly because of that. They can get as bad as loosing 80% of thier charge in less than a week time.

 

[Cavelightchris]

Well I used to believe those were the only two worth a crap, and coincidentally enough I went to this guys website who makes these expensive triple P7 headlamp casings for bikers, and on his website he too only recommended either Eneloops or Energizers.

I am having my doubts now, could you elaborate on your "out $150" story? I would love to hear it.

 

[VidPro]

i dont really have to tell MY story you can read about hundreds of other people with the same problem with a search of them on any search engine, at any ratings location, or opinions or reviews, or just search only here.

i use many rechargables since long and long ago, just for the job, i have to have about 36 charged and ready to go at all times.
plus many packs of li-ion , and some 9v and belt packs for 12v large, and all that stuff. it has to be ready to go at a moments notice, and if i use tossaways, they basically all have to be tossed after a job (unless they werent used) , because all the bats must be full and ready to go, one error, and i can lose like $1500 and could even get sued.

we had used many rechargable batteries throughout the years, when 2300, and then 2500 came along we bought loads of them, just like eveything else, problem was after about 30-50 cycles and about 1 year of time, they would no longer hold a charge. they would still test after an imediate discharge the full ammount, but drain themselves rapidly.

bought all new chargers (as usual) that charge singularly, started to try and treat them like they were glass on silver platters, tried to discover any problems with charging.
then we re-buy again, and tried different brands, and round and round, same thing after plunking down huge sums in reusable batteries, most of them didnt make my money back (when you include the time and charger costs), even though they did the job.

we still had (and have actually) lower capacity batteries that did stay charged, but all the high caps croaked and were completly undependable.

energysers were a big part of all that, bought the 2300s, the 2500s, and they were all junk after what i concider a very short time, i am just luckey we KNEW something about the batteries, or i would be out a few whole JOBS where my "bottom would be grass".

 

[Marduke]

Lot of mistakes in there. Lithium primary cells still need recycling, the self discharge of Eneloops is wrong, recommending Energizer NiMH will lead to many disappointed people when they crap out. You don't go into recommended charge practices or chargers, one of the most important aspects.

I am writing a ~4-6 page battery article for the Huntsville Grotto newsletter, I'll send you a link when it's done.

 

[Hondo]

Regarding Energizer 2500's, just search on Energizer+2500 and read. Here is a typical exchange:

https://www.candlepowerforums.com/threads/238015&highlight=energizer+2500

I have a pile of these, all dead within a few days of charging, save just a couple of exceptions which still hold charge like a normal NiMH. You can use these things straight off the charger, which is why I keep them around, but no one should buy these things knowing what they are getting, NiMH's should be better. I don't know of a current, decent, AA NiMH product from Energizer. A deeper dig will show that the 2450 mAh cells are not looking any better. The AAA cells seem to do fine, although I have a few of those that have to be charged on a "dumb" charger because of high resistance, but they still hold their charge. There is some talk on some new Energizer AA's that are labelled 2300 mAh, but they may just be a re-introduction of an older design:

https://www.candlepowerforums.com/threads/242648&highlight=energizer+LSD

 

[Cavelightchris]

Lot of mistakes in there. Lithium primary cells still need recycling, the self discharge of Eneloops is wrong, recommending Energizer NiMH will lead to many disappointed people when they crap out. You don't go into recommended charge practices or chargers, one of the most important aspects.

I am writing a ~4-6 page battery article for the Huntsville Grotto newsletter, I'll send you a link when it's done.

I thought I saw on the Discovery Channel that AA lithiums are made of nothing but water, so technically you can just throw them in the trash. I wonder if you are thinking of Li-ions that need to be recycled and not the Energizer AA's?


Actually I did mention all of that a few times:

* I mentioned charging battteries slower is better than charging them faster, and the same goes with discharging them.

* I explained what a smart charger is and how they prolong the life of a battery.

* I also mentioned what conditioning is and how to do it.

O and you are right, Sanyo claims they discharge %15 a year and not %5, I'll have to fix that.

Well thanks for reading it over and recommending the article, I can't wait to read it.

Chris

 

[Cavelightchris]

O and thanks everybody for the information on how crappy the Energizers are, I will remove all of that.

Is there any store bought rechargeable that you all could recommend?

Can't you get low self-discharge Tenergies at Walgreens or something, are they any good?

 

[Marduke]

I thought I saw on the Discovery Channel that AA lithiums are made of nothing but water, so technically you can just throw them in the trash. I wonder if you are thinking of Li-ions that need to be recycled and not the Energizer AA's?


Actually I did mention all of that a few times:

* I mentioned charging battteries slower is better than charging them faster, and the same goes with discharging them.

* I explained what a smart charger is and how they prolong the life of a battery.

* I also mentioned what conditioning is and how to do it.

O and you are right, Sanyo claims they discharge %15 a year and not %5, I'll have to fix that.

Well thanks for reading it over and recommending the article, I can't wait to read it.

Chris

Energizer lithiums do need to be recycled, same as any other battery.

You also don't quantify what is fast and slow charging. "slow" by most definitions is actually quite bad, with an increased risk of missed termination. "fast" to most people means a couple hours, which is exactly the range you SHOULD be in. An ideal charge takes 1-2 hours for an empty battery, which is 0.5-1C.

 

[Cavelightchris]

Are you %100 positive? I wish you could site your findings if you read that somewhere, because I am in disbelief, because if it's better for them to discharge them slowly you would think the same holds true about charging them. I guess you do know a lot more than I do, but I read on here a few times that charging batteries fast is worse for them than charging them slowly, so I figured I did not need to specify any specifics since the packaging normally tells you what the deal is. I am fixing the article now, and I quoted you about the charging and so I hope you are right.

So is the 300mA discharge of my Sanyo actually a bad thing? I think it takes 8 hours to charge my Eneloops with that thing.

Do you know what is the preferred rate of charge in mA?

O and what was the 0.5 - 1C thing, I didn't get that?

 

[Niconical]

I've not read the article yet, will do shortly, but first I want to reply to your comment to Marduke about the charge rate for nimh. Marduke is 100% positive, as is everyone else. 0.5c-1c charge rate, AKA it should take 1-2 hours to charge. Page 1, paragraph 1 of the nimh handbook, most of which was written by members of this forum :naughty:

I'll read the article now.

 

[Niconical]

Read it. Some good advice for the novice. I have nothing to add that hasn't already been mentioned, but I will repeat what others have said, seriously, ya gotta get rid of the E word. Even if you have to crawl up into the interwebz and rub it out with an eraser, do it :huh:

 

[Cavelightchris]

O don't worry, if you re-read it right now(well in a few minutes, it takes a while for it to actually update) the E word is only there to bash the company (like how VidPro wanted), but I do like their 3 and 6 LED headlamps (with Nichia's), but o well they are actually made by a different company anyhow, and Energizer just puts it's name on it.

And I fixed the charging information.

Thanks again guys!!!

So can anyone recommend a cheap smart charger(like my Sanyo) that charges at a rate of 0.5 - 1C(unlike my Sanyo) ?

 

[Anders]

Hello Cavelightchris.

If the CPF community should recommend only one charger I am pretty sure it would be Maha Powerex MH-C9000.

Here you can read about it , by Silverfox.

Anders

 

[Niconical]

So can anyone recommend a cheap smart charger(like my Sanyo) that charges at a rate of 0.5 - 1C(unlike my Sanyo) ?

Whatever you budget is, there are 3 main factors to consider for a nimh charger. 1, is it just generally well made and works well, delivers its charge efficiently, senses when the charge should be coming to and end, that kind of thing. 2, does it charge at an acceptable rate. It's easy to think for example that Duracell are big in batteries, they make a charger, it must be a good charger at the right speed. Not always the case though. 3, it should ideally have separate channels. This means that each slot is treated indivdually by the charger. So for example you insert 4xAA at the same time, each with a different level of charge in them. A charger with separate channels will put in only enough charge for each cell, then terminate, usually with an individual LED to indicate "DONE", rather than just pumping in the same amount to all. An additional useful feature is the option to have it discharge the batteries for conditioning, much more practical than your "headlamp set on low and leave it on" idea.

I can't really advise on which though as my nimh chargers are either at the higher end of the ladder and relatively expensive, or the more basic ones would be harder to obtain in the USA. I'm sure there are plenty of members who can advise on something that will fit your needs, but if you specify how much you want to spend it would help a lot.

 

[Cavelightchris]

$10 would have been nice, but it's nice to know that the ultimate charger can be had for a lot less than $100.

Thanks guys!

 

[Hondo]

Are you %100 positive? I wish you could site your findings if you read that somewhere, because I am in disbelief, because if it's better for them to discharge them slowly you would think the same holds true about charging them. I guess you do know a lot more than I do, but I read on here a few times that charging batteries fast is worse for them than charging them slowly, so I figured I did not need to specify any specifics since the packaging normally tells you what the deal is. I am fixing the article now, and I quoted you about the charging and so I hope you are right.

So is the 300mA discharge of my Sanyo actually a bad thing? I think it takes 8 hours to charge my Eneloops with that thing.

Do you know what is the preferred rate of charge in mA?

O and what was the 0.5 - 1C thing, I didn't get that?

There is no bad advice here, but I would like to clarify a bit. The reference to 0.5 - 1C, in which "C" is the capacity of the cells, is for "quick", or less than overnight-type times. So a 2000 mAh cell should be charged at 1000 - 2000 mA. The reason is that most smart chargers determine when the cell is done by what is called the negative delta V method. This just means that it detects that the voltage of the cell has stopped increasing, and has actaully started to drop, which is what will happen at the end of the charge. If the cell is being charged to slowly, the drop in voltage may not be detectable by the charger, and it will miss termination, and keep charging the full cell. You already know this is bad. So that is why the 0.5 - 1C charge rate recommendation.

Now, there is NOTHING wrong with charging cells at a slower rate, and the cell could live a little bit longer as a result, so long as the charger does not overcharge at a relatively high rate. A relatively high rate would be something significantly above C/10, or 200 mA for our 2000 mAh cell example. Using C/10 for overnight charging is a perfectly safe way to charge cells, and charging them beyond full at that low a rate won't cause significant damage. It is the rate used for "break-in" in the excellent Maha C9000 charger.

There are some chargers that seem to get away with consistantly terminating at the "scary" mid-range charge rates, like 300-500 mA for AA's. The Sanyo MQN05 and the Duracell Mobile and Power Gage chargers are some notable ones I have and use. See Mr Happy's remarks on the Sanyo here:

https://www.candlepowerforums.com/threads/241005&highlight=sanyo+charger

 

[Marduke]

Yes, there are exceptions to the rule. I also have very good results from my Duracell Mobile charger.

 

[MorePower]

One major problem is your statement that "2 different alkalines" were tested. The Rayovac Heavy Duty cells aren't alkaline (they're zinc-carbon), and wouldn't be expected to hold up to a 500mA drain. Rayovac alkaline cells should perform at least as well as the Energizer alkaline cells that were tested.

 

[Cavelightchris]

I know this is going to sound like a noob question, but I am not %100 sure how the Apex's circuitry works, and so here is the question:

When the Apex is running it's LED at 600 mA, what is the amount of drain each battery sees in mA?

Even a ruff estimate with a tiny explanation would be greatly appreciated. My guess is that each one sees 600 mA of drain, but I could be way off.


ALSO:

Does anybody know if this Sanyo charger is any good, model number: NC-MQN06U ?

Here is a pic of it: http://www.batteryjunction.com/sanyo-charger-eneloop-4-aa-batteries-kit.html

I did some tests with it, and if you fully charge a Eneloop and let it cool down, then put it back on the charger, the charger will only charge them for a few minutes (maybe 10 at max) before it stops charging them / the lights stop blinking.