Rechargeable Batteries - Yes or No?

TheFifthElephant asks: "I currently use quite a few devices that require various size batteries and I feel horrible just tossing them when they die. I saw a recharger at a retail store today and was thinking to myself how much waste it would reduce by using rechargeable ones. Which units have you used happily and/or which units have you heard of/read about satisfying someone else? Are the more expensive units better? What chemical rechargeable batteries last the longest/recharge the most?"

NiMH

[sterno]

I use NiMH batteries for my wireless mouse, and my camera. Got a simple charger over at radioshack, and it works quite well. The batteries provide equivalent if not better power than alkalines and though they cost more up front, are definitely cheaper in the long run.

lower impedance

[Alain Williams]

Although rechargables seem to have a slighly lower nominal voltage than the equivalent disposable, I am told that they have a lower impedance (resistance). The result is supposed to be a risk to some equipement. This is why some things have the label ''do not use rechargable batteries''.

However, I have always ignored the above and never had any kit die as a result of using rechargables.

Re:put dead batteries in sun for more life

[red floyd]

Yeah. A buddy of mine keeps his disposables in the freezer for later use. Then they "wouldn't work" in something. I told him to warm them up and then they were fine.

What about rechargable akaline?

[gotr00t]

Remember that Rayovac sells rechargable akaline batteries as well, and like Ni-MH, are not AS bad for the environment as Ni-CAD.

Moreover, they do have a distinct advantage: they're cheap and of high capacity, though not good for many recharge cycles. While a pair of Ni-MHs cost about $8, a pack of 4 rechargable akalines costs about the same price. Like regular akaline batteries, they have pretty high capacity (about 2200(I think) mAh for a AA, compared with the low 1000's range for most Ni-MHs), and actually come charged, with a long shelf life without discharging itself.

I use these batteries for most of the things that don't work with Ni-MH (graphing calculator, small electronic devices), as these have the usual 1.5 volt, instead of the 1.2 volt on most rechargables. Their downside is the fact that they can only be charged 10-20 times before they leak (the package said 40).

Re:Save the environment..

[The_K4]

There's not much in the way of real copper in pennies any more. See here [usmint.gov] So you'll need pre 1837 pennies to get pure copper!

A question of efficiencies

[levin]

I really wonder if the damage done to the environment and cost of recharging a battery is really all that much better than buying disposable ones. Especially if you factor in the loss in efficiency associated with the delivery of AC power, the conversion to DC and the interface between the charger and the battery (not to mention leakage). Of course, that raises another question: what/how efficient are the methods used by Duracell and the like to build disposable batteries?

Re:Just researched this...

[bubblegoose]

I've had the same charger for about two years, the thing is great. Plus the optional car charger cord makes this even better (although I had to run a constantly hot fused feed to my cigarette lighter).

One thing about NiMH, they need to go through about 3 dicharge/charge cycles before they come up to full capacity.

The place where I bought mine says to keep your batteries in a sealed bag in the freezer [greenbatteries.com] when not in use, they self-discharge about 40% in about 30 days [greenbatteries.com] at room temperature.

Re:All About the Same

[Kaa]

Most of the brands of rechargeable batteries have about the same performance.

Bullshit. First, there are different kinds of rechargeables -- NiCd, NiMh, Lithium, to name a few most widespread. Their characteristics are quite different. Second, as usual you typically get what you pay for.

But not buying batteries from an electronics store is good advice. They are horribly overpriced there, any brand...

Rechargeable batteries, like toothpaste, is a commodity product.

Toothpaste? You mean you alway buy the cheapest toothpaste you can find?? :-)

When you buy a product, you indirectly support the value system in the country of origin.

I do? How interesting... Is it one of those "if you do drugs you support terrorism" rants?

"Made in USA", "Made in Japan", or similar Western-country label is usually a safe bet in terms of (1) the quality of the product and (2) the value system in the country of origin.

Thanks for a good laugh... To start with, Japan is not a Western country. To continue, US produces large amounts of very shoddy products. "Made in USA" is definitely not a guarantee of quality. And what was it about value system again?

avoid "simple" chargers, good ones are cheap

[frovingslosh]

First of all, use NiMH batterise, avoid NiCads. NiCads have much lower capacity, and use very toxic materials. NiCads might still be of some use in very high current situations, but overal are obsolete (but people are still willing to sell them to you).

Also, when buying NiMH batteries, pay attention to the mAh rating, which is how much power they hold. AA NIMH batteries might range from 1200mAh or lower to 1950 mAh (the best capacity I've bought so far). This gives you a good indication of how long the batteries will last between charge; clearly there is a big difference out there. And the more expensive batteries do not always have the greatest capacity.

On chargers, there are a lot of different and bad chargers out there. The worst never shut off, just tell you to be sure you only charge batteries for x hours. If you forget and overcharge you can destroy the batteries! Also, if the batteries were not completely discharged then you can overcharge and destroy the battery even if you charge for only the time stated.

The next worst chargers have a simple timer in them and do shut off after x hours. But they still can overcharge a battery if it wasn't fully discharged, or if you try to charge a lower capacity battery. And if you get a higher capacity battery and try to charge it, it will not fully charge.

My rule of thumb is that I never use a charger that insists on charging batteries in pairs. Such chargers cannot sense individual cells, which would allow them to stop charging each cell when it is fully charged. There are a few chargers out there that do sense individual cells and shut off properly though. I think Best Buys sells one for about $30. However, the $9.99 Ray-O-Vac NiMH charger sold at WalMart does this fine. I'm not a Ray-O-Vac fan at all, but I do use and recommend this charger.

And take batteries out of any charger when charged, never trust chargers that promise to keep batteries ready by trickel charging them. I've had them cook batteries.

Again, I want to stress that one should never use chargers that do not sense individual cells and that have to charge in pairs. I have several (I just got one with the 1950 mAh batteries I bought recently) but never use them (I bought the batteries and recharger just to get the batteries, the price was right). Don't risk your expensive batteries to a cheap charger, it will seem to work fine for a while, then you will find that all of you batteries have started leaking and failing.

Remember to look for and pay attention to that mAh rateing when buying batteries.

In applications where the battery might last for years (TV remote control for example, or garage door opener) do not use rechargable batteries. Use Alkaline batteries in these applications; rechargeables will loose their charge too fast, and alkalines are the best choice (I have a garage door opener with the same alkaline battery in it for 19 yeras now).

And thanks for asking here rather than doing a simple Google search on the topic.

Re:NiMH

[sacherjj]

You can usually find the lithium AA in the photo battery section of a store. It is 3.6V, so using it in regular devices would require a AA blank, which is a conductor shaped exactly like a AA battery.

I haven't seen these, since very old 12 V powered radios. They were used with the radios when alkalines were used. Normally 10, 1.2V NiCad AAs were used in the radios. If you used alkalines, you needed 8 1.5V AAs. To keep from hurting the radio, you used two of these AA shaped conductor blanks.

Re:NiMH

[butt-rock camaro]

The amount of time a battery lasts for is highly dependent on use. I use NiMH batteries in my camera flash (Minolta 2800AF), and they absolutely kick ass over Alkalines because they maintain terminal voltage (and thereby keep the recycle time short). Overall, NiMH cells probably perform significantly better than alkaline cells in high discharge rates.

Alkaline cells probably fare much better in things like wall clocks, remote controls, and any other device where infrequence of use is a bigger deal than overal capacity. NiMH cells can (and typically will) self discharge in a couple of months of inactivity.

At this point, I see no reason for people to use NiCd batteries anymore, due to their significant memory effect, toxicity problems, lower unit capacity (compared to NiMH), etc. But NiMH cells really are ready for prime time in many devices, and are certainly more cost effective in the long run.

Disappointing voltage from NiMH

[Omega]

I experienced the same ethical crisis as the poster. I have a shower radio/cd player [amazon.com] that takes six (6) C-size batteries and drains them after 6 hours of radio usage or 3 hours of cd player usage.

Obviously my main problem is that this device makes horrible use of power (by comparison my Riovolt SP250 radio/cd/mp3 player lasts 15 hours on 2 AA batteries). I was bothered by the number of batteries I was throwing out and the cost of continually refueling the player (bad for the environment and for me).

I decided to try rechargeable batteries. I bought 3 packs of Energizer NiMH rechargeable C-size batteries [amazon.com] and an Energizer battery charger [amazon.com]. Unfortunately, I didn't pay attention to the fine print on the batteries -- the voltage is only 1.2V (instead of the alkaline's 1.5V). When you add up the voltage from all six batteries, you only get 7.2V for NiMH vs. 9V for alkaline. And the CD player needs the 9V to drive the Vcc on the amplifiers.

I was going to try rechargeable alkaline batteries, but judging by some of the comments here it sounds like other people's experiences with them are not so great.

Re:Save the environment..

[DougMelvin]

Actually the first light bulb used a bamboo filament. So light's in Egypt are not too far-fetched

Re:NMH good, need help with lithium.

[iabervon]

First of all, there are three different battery chemistries involving lithium: (metallic) lithium, lithium ion, and lithium polymer.

Lithium batteries aren't generally rechargeable.

Li-ion batteries are rechargeable, but a single cell is about 3.7V (as compared to 1.5V for a alkaline cell or 1.2V for a NiCd or NiMH cell); so they could make a 5/2 AA battery out of it (great for devices that take 10 AA batteries, arranged just so...) or include a bunch of electronics to get a reasonable voltage out and handle charging in a regular charger, which would be a huge pain. There is a standard 7.4 Li-ion battery form factor, though, which is reasonably general.

Lithium polymer batteries are new and somewhat obscure and hard to make (in fact, real lithium polymer batteries are not expected to be available until 2005; currently there are only hybrids). They (like metallic lithium, for that matter) are 3.0V, and not suitable for AA applications, although you can find 3.0V two-AA battery objects. Lithium polymer batteries will also solve the general lithium problem with exploding or bursting into flame if mishandled.

Dying Lithium Ions

[Comatose51]

Anyone know how to resurrect one of these batteries that supposedly don't have a memory effect? I just brought a new one and it's now down to 1/3 capacity after only a few months. I think it has to do with the fact that I leave my laptop plug in all the time.

Clear memory in the freezer

[jason99si]

I've found that my Lithium Ion laptop battery stopped holding a charge. A friend suggested draining it, then popping it in the freezer for a day or two to finish the job. charged it back up and it was good as new (or close).

the chemistry behind it? who knows. worked for me.

Re:All About the Same

[willtsmith]

NiMH recharcheables make Alkaline rechargeables look pretty week. They make normal alkaline batteries look weak as well.

I've had very good luck with Ray-O-Vac. Ray-O-Vac also makes higher capacity line of NiMH batteries than other manufacturers (check the labels for the mAh rating).

Re:I like lithium beter than NiCad

[Myself]

Who modded that up? The memory effect [wikipedia.org] only exhibits itself in situations of very regular charge/discharge cycling. Regular deep discharges damage the electrodes and shorten the cycle life of a battery. All rechargeable chemistries will last longer if they're not discharged too deeply. Lead-acid ("car") batteries are particularly sensitive to deep cycling, but it applies to NiCd and NMH too. Don't flatten them if you can help it!

It's important to differentiate between batteries and cells when talking about deep discharge, too. An individual cell can be taken down to 0v without major damage. Once in a while it can be beneficial, to reform the electrolyte. However, in a battery pack, which has several cells wired in parallel, discharging until "flat" can cause serious damage: The cells in the pack are not identical, some of them hold slightly more charge than others. As the pack voltage drops, some of the individual cells near zero, cross it, and actually get reverse charged by the other cells in the pack. Reverse polarity destroys cells very effectively. Packs should never, never, ever be discharged below 0.5v per cell.

As to the parent post: Lithium-ion chemsitry produces 3.6 volts per cell, which is fine if you're designing a new device, but it makes them unsuitable for retrofit or use in standard AA applications. Lithium secondary cells are also tremendously sensitive to current and voltage limits during charging. Exceeding their specifications can cause pressure buildup, violent cell rupture, damage to the device and possible injury to the user. Because of liability, manufacturers don't sell bare lithium secondary cells to Joe Hobbyist. You can buy packs, with the appropriate overcharge protection circuit already wired in series.

Lithium primary (non-rechargeable) cells, on the other hand, are very handy in certain consumer applications: They produce 3.0 volts per cell, exactly double that of the traditional carbon-zinc and alkaline chemistries. They're also very light. The CR-V3 battery is designed to drop into compartments that would normally hold a pair of AA's. Certain digital cameras are designed with the CR-V3 in mind, giving the user a lot of flexibility in battery selection: My Olympus C-2100 can take four AA's of any chemistry (although alkalines don't last very long), or a pair of CR-V3's if I want to travel light and don't mind the price premium.

Since 9 volts is an even multiple of the Lithium primary cell's 3-volt output, lithium-based 9-volt batteries are now available for applications like smoke detectors. They're also ideal in certain LED flashlights, where the low discharge current is well-suited to the lithium chemistry, and the light weight means that many such flashlights will float, which they wouldn't do if heavier alkaline batteries were used. However, none of this is relevant to rechargeable applications.

Actually WalMart is excellent

[BoomerSooner]

WalMart is generally thought of in economic studies to be a large reason that inflation has remained so low in the US despite 2 recessions and 2 wars in the last 15 years. Plus they have one hell of a large workforce. The way they have helped to keep inflation down (grocery as well) is by making the suppliers give them their best rate. When a company can tell Disney to piss off if their price is too high (ever bought a toy at the wonderfully overpriced world of disney?), they have enormous impact on the economy as a whole when they have 10's of thousands of stores. Personally I prefer to shop at Target because it's not quite so "White Trash", but different strokes for different folks.

Uniross

[henc]

I strongly recommend Uniross 2300mAh 1.5v rechargeables. Before I got those I had to run the camera on Radioshack-type buy-and-toss batteries. They lasted for about 20-30 pictures without LCD and flash. The new rounds (I bought two rounds of rechargeables, to always keep an extra pair handy), are accountable for at least 250 pictures per round. With some LCD, deletions and flashes here and there. -If it's not less expensive to run on rechargeables, it's definitely more comfortable! h

Re:Actually WalMart is excellent

[Unordained]

Wal-Mart Wages Don't Support Wal-Mart Workers, Stan Cox, AlterNet, June 10, 2003 [alternet.org]

Yup. They save money on their suppliers. But never would they think to do so on their employees, no ... Workforce is the most expensive part of a business; no reason to expect they wouldn't try to trim the edges there.

Re:NiMH

[willtsmith]

Rechargeable alkalines certainly did have advantages BEFORE NiMH came out. But, boy do the NiMH batteries kick the crap out of Rechargeable Alkaline.

The good news is that it you DON'T buy them at Radio Shack, they are VERY affordable. You can buy a Ray-O-Vac charger with AA batteries for $20-$30. You will get especially good results with your GPS receiver. Once you go NiMH, you will resign your rechargeable alkalines to remote controls.

good battery store

[leery]

http://thomas-distributing.com/

they seem to get the latest, highest capacity models, various brands.

NiMH working great for my dad's digital camera and lousy for my Visor. Opposite is true for disposable alkaline. Go figure. Maybe NiMH is good for sporadic high current draw, alkaline better for trickling and low-current apps? Anyone?

I use maha...

[slasher999]

They seem to have the highest life batteries. I just bought a bunch of 1800mAh cells and they work great. I use them in my scanner (scanning receiver - a radio), frequency counter, digital camera (only around the house, not on trips), and a few other devices that are pretty high drain. I've had good luck with Maha cells and the cheapest charger I can get for them. I purchase all my cells and chargers from Thomas Distributing. Always get good service from them.

Pure Energy

[Phantasmo]

Here in Canada we have Pure Energy [pureenergybattery.com], a great brand of rechargeable alkaline batteries. I've only seen them in AA and AAA, but they cost about the same as non-rechargeable alkalines, can be recharged 100 times, and perform excellently in palmtops and cameras...

and Laser Challenge gear.

Biding my time.

[WalterDGeranios]

I've promised myself not to buy any portable electronic devices for the next couple of decades. I'm holding out for the micro-engines [slashdot.org].

Re:Nickel Metal Hyride

[afidel]

The iPod uses a lithium polymer gel pack, despite what people claim it can eventually degrade enough that it exhibits similar symptoms to memory (I think this is mostly due to exposure to excessive heat). There is a company that sells a replacement for the battery in the series 1 and 2 iPod's that are actually higher mAh rated then the Apple origionals.

Re:NiMH by far, and retrofittable to NiCad stuff

[olman]

You want to replace the charger as well! NiMh charger is NOT necessarily compatible with NiCad. It's not that the charge current is dissimilar as such, it's that the batteries behave differently when they top up and the charge monitor can become confused.

Of course if you use a "dumb" charger that just pours on the current for X hours, there should not be a problem. But be vary of "smart" chargers which allow you to keep the battery pack connected 24/7.

Re:Actually WalMart is excellent

[Anonymous Coward]

There is a libertarian thing against unions being granted special favors from the government. But without that, unions would fall apart because no company would be forced to hire union workers.

That and because if you've studied labor economics, you'd realize how much wealth labor unions destroy.

Re:Screw the environment you posers

[Anonymous Coward]

There's no need for us to screw the environment, you Yanks have already done it. 4% of the world's population, 25% of the world's pollution.

Re:Save the environment..

[Muad'Dave]

For the record, in 1982 the penny was changed from 95%Cu/5%Zn to 97.5%Zn/2.5%Cu (the copper being a thin cladding on the outside). The weight changed from 3.11g to 2.5g. If you scratch a modern penny, you can see the shiny silver zinc under the copper cladding.

Interesting bit of trivia: The old and new pennies sound very different when dropped onto a hard surface: the old ones have a bright ring; the new ones are considerably duller in tone. You can sort them by sound!

Zinc-Air?

[muchandr]

Whatever happened to Zinc-Air rechargeables?

They were supposed to have even higher energy density than Li-Ion and family, but haven't seen them recently outside of niche hearing aid market. Is there a problem with them breathing atmoshperic air or something?

Anyone remember "dummy" cells?

[SailFly]

I used to work at Radio Shack (15 years ago) and remember the some devices would require the use of dummy cells if alkaline batteries were used. The dummy cell was a plastic insert with a shunt wire that basically filled the place of a battery cell. This way, devices that supported NiCd would use all Rechargable cells, or while using Alkaline, you would insert the dummy cells to adjust the voltage.

It seems that most devices now are engineered only for alakaline, and have no room for extra cells to create the required voltage.