I was standing in line at a local electronics store the other day when I struck up a conversation with the guy ahead of me who had a basket full of battery chargers and AA rechargeable batteries. It turns out he had decided to replace all of the batteries in his house with the rechargeable kind. Between the batteries and the chargers this guy plunked down over a hundred bucks!
He was so proud, telling me about all the money he was going to save.
I didn’t have the heart to ask him if he had the same typical electronic devices found in most homes, because if he did then he probably ended up spending a lot more money than he should have.
Rechargeable Batteries Aren’t Always Cost Effective!
I realize many people want to convert to rechargeable batteries for environmental reasons, which is fair enough. But the truth of the matter is this: when cost is the primary discriminator, low current-draw devices simply don’t warrant the extra expense of rechargeable batteries. That’s because the batteries of low current-draw devices are typically changed so infrequently that the payback period for equivalent rechargeable batteries would be too far long to justify the investment!
For example, it makes much more sense to use traditional alkaline batteries for low-draw devices like your wall clocks, radios, smoke detectors, programmable thermostats, and remote controls because they lose power at a much slower rate than rechargeable batteries.
And because traditional alkaline batteries can hold a charge for years when not in use, they are also the better choice for items that may sit unused for long period of time, like your alarm clock back-up battery and emergency flashlights.
When it comes right down to it, these low current-draw and/or low-use devices make up the great majority of battery-driven products in the typical home.
Okay. So When Do Rechargeable Batteries Make Sense?
Rechargeable batteries are really intended for moderate to high current-draw devices that get at least moderate use. Typically, these are devices that require a battery change every 30 to 60 days.
In my house the only item that clearly met that criteria and, therefore, justified the added up-front costs of rechargeable batteries, was the kids’ Wii gaming system. That is a perfect example of a high-use device where rechargeable batteries will save you a lot of money in the long run.
But for my household those are the only items where rechargeable batteries make sense.
“But, Len, what about my wireless keyboards and mice? Those get a lot of use!”
Well, as my article on the practicality of wireless mice and keyboards noted, rechargeable batteries didn’t even make financial sense for those devices, based upon my battery usage over an 18-month period – I only spent a little over $18 on replacement batteries during that period. But a set of eight good rechargeable AA batteries (five for the mouse and keyboard plus three spares) would set me back roughly $24. Add in the cost of the charger (a good one can run upwards of $40) and you can see that the payback period on the rechargeable batteries becomes a real issue. Remember, rechargeable batteries eventually go bad too, so you’ll need your batteries and charger to last at least until the payback period is reached if you want to recoup your costs in a reasonable amount of time.
How Do I Know Which Type of Rechargeable Battery to Buy?
If and when you decide you want to buy rechargeable batteries, you’ll need to know that there are essentially four types to choose from: nickel metal-hydride (NiMH), nickel cadmium (NiCad), rechargeable alkaline, and lithium ion.
NiMH rechargeable batteries typically perform better than NiCads and are free of toxic heavy metals. Generally speaking, NiMH is the best all-around choice for most rechargeable battery applications. As an added bonus, most NiMH battery charger systems can accommodate NiCad batteries too (although the opposite is not true).
NiCads are being phased out in favor of NiMHs not only because they are losing the performance war, but also because of their inconvenience; the heavy metals used within the NiCad are toxic and require special disposal needs.
Rechargeable alkaline batteries have only two real advantages over NiMHs and NiCads: low cost and no need for special recycling. Otherwise, their long-term performance and recharge characteristics make these batteries a poor choice. Rechargeable alkaline batteries also require a special charger, which reminds me: don’t ever confuse rechargeable alkalines with the typical disposable alkaline batteries that are sold everywhere from 99-cent stores to the local grocery market – although some people do it, those batteries cannot be safely charged.
Lithium Ion batteries have great performance and can go unused for long periods without losing their charge. The big drawback is their price; not only are lithium ion batteries much more expensive than other types of rechargeable batteries, but they also require a special charger. Use them for rarely-used or high-drain devices like laptop computers, digital cameras, cell phones or portable televisions.
To help you decide which rechargeable battery is right for you, here is a trade summary I put together of the four basic options (click on the image to make it larger):
Some Final Thoughts and Recommendations
- A bad battery charger will prematurely age and greatly shorten the lifespan of your rechargeable batteries. Cheap chargers work too quickly, thereby heating the batteries, which damages them over time. Good chargers will keep your your batteries from getting too warm.
- Batteries should always be removed from their chargers after recharging.
- More expensive battery chargers extend the life of your rechargeable batteries by properly monitoring and controlling the charging process; many also shut off when charging is complete.
- If you do use rechargeable batteries, be sure to keep several spare batteries ready to go at all times so you can swap them out when needed.
- If you do choose to swap out all of your devices with rechargeable batteries, you can spread out your initial costs by replacing only the moderate-use devices first. You can then buy rechargeable batteries for the low-draw devices as needed.
- For info on NiMH rechargeable batteries and battery chargers, check out this article from MetaEfficient.
To Summarize…
Rechargeable batteries are great for moderate to high use devices that drain batteries quickly, but they are not cost effective for low current-draw and/or low-use devices – and it is the low current-draw devices that tend to make up the great majority of battery-driven products in the typical home.
Hopefully, the gentleman I met at the hardware store has a lot of high current-draw, frequent-use devices at his house – otherwise, he probably made a big mistake.
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Nice article, Len.
Why are there some devices that refuse to work with rechargeables at all? I have some kids’ electronic toys that won’t function at all unless they have disposable Alkalines. Some that come to mind are LED flashlights, blinky-noisy kids toys, etc. Maybe the cheap AAA rechargeables are to blame too. Can you recommend how to effectively compare price/performance on NiMH AA/AAA rechargeables?
thanks, maybe topics for a future article…
Dean,
I am going to put on my electrical engineering hat here to answer your question, but I will try not to get too geeky here…
I’ll give a short answer to both your questions, followed by a more technical explanation.
Short answer to question 1: The voltage drop on rechargeable batteries is often too high to get the needed peak power from the batteries.
Technical answer to 1: Alkaline batteries have very high peak current ratings and good Watt-hr numbers (capacity). This is good for LED flashlights, which normally pulse the LEDs on and off at a high rate to get the brightness and avoid droop. Kids’ toys that have motors require high starting current and, therefore, alkaline are best for those applications too.
Short answer to question 2: I think for home applications $/Amp-Hr rating is the way to go.
Technical answer to 2: Normally, the battery industry compares batteries in this order of priority – energy density, cost per WHr, Amp-Hr ratings, pulse load capability (internal impedance), charge rate.
Hope that helps!
Hi Len,
Nice job explaining the differences & economics
.
Re the Alkaline/rechargeable debate, alkaline (and the older carbon-zinc) batteries have a terminal voltage of about 1.5V unloaded when good. Rechargeable NiMH and NiCad are about the 1.2V area. Some electronics won’t start at the lower voltage.
Also, NiCad batteries are regarded as superior to NiMH (and Lithium Ion IIRC) for low temperature applications.
RP
Wow, there are still significant amount of people who don’t know LSD (low self discharge, which maintains 80% of the charge in a year) NiMH batteries. Google eneloop to learn more.
@Richard: Thanks. And you are correct about the NiCad and Lithium Ion for low temp applications. Lithium ion is especially effective in this regard.
@vicaya: You are forgetting the cost equation. Alkaline AA batteries cost 30 to 40 cents each. It makes almost zero sense from a financial perspective to justify paying approximately $4 per AA LSD NiMH battery and another $20 minimum for a charger – those rechargeable batteries would go bad before you ever reached the payback period.
Also, I guess, the main point you’re making about monetary cost would apply just as much to environmental cost? The numbers will be different (I don’t know quite how they stack up, & would be interested to hear!) but the basic argument – that if the batteries are only being replaced rarely, then the one-time cost of changing over outweighs the reduction in replacement costs – seems to be just as valid.
Good to know, but this article leaves out the convenience factor. It’s easier to have rechargeables on hand than to run to the store to replace the batteries for my mouse.
@Smarty: I think a lot of people would disagree with you. There really is no inconvenience at all if you buy the alkaline batteries in bulk, which you should be doing anyway. When I see the supply running low, I simply make sure I pick up more alkalines at my earliest opportunity.
Remotes have suckky range with rechargables in them because of the lower voltage.
Also my cordless headphones will go louder with less distortion when run off alkalines. Shame the rechargable alkaline systems never got anywhere – I guess the 20 or so charges that you get out of them was not enough to swing most people to them.
I actually just bought a Lacross BC-9009 Battery charger for $40 and 4 packs of Eneloop LSD batteries to replace my aging Energizer rechargeable setup. I think its a good investment for several reasons. First, everything seems to need batteries these days. 3 Wii remotes + 2 XBox remotes + 3 remotes for the entertainment center + Keyboard/mouse + Wii Fit Board + kids toys + other misc items. Second, is that to buy batteries in bulk, I would have to travel 25 miles to the nearest Wal-Mart — Highly inconvenient. Third, it is the environmentally right thing to do. Instead of landfills filling up with batteries, my batteries are charged by our town’s wind powered grid.
Once you get over the hump of buying the charger, I think it makes more economical sense to get the rechargeables. At the end of the day, the rechargeables are going to outlast the disposable kind.
Provacative article, but I am not buying into your economic argument. Look at your keyboard/mouse example. $18/year disposable vs $24 for rechargeable (but You included 3 extra which is not a fair comparison – should be 5 at $15. Just after 1 year you are ahead on batteries) also the rechargeable last much longer than one year. My experience is easily 3 or more years. And if you are using rechargeables for all your battery needs the charger costs are spread over more batteries making the charger costs insignificant.
Regarding convenience, it does make since to have some disposables on hand for when your rechargeables run down and you need battery power while your are charging.
So, the guy in front of you was probably doing it right. Buying a lot of rechargeables which means he will spread the charger costs over more batteries.
My MP3 player go through 1 AAA every two days and have done so for the last three years.
Price comparison (local prices):
4x LSD NiMH AAA’s: $8.50 + charger $12 = $20.50
500x Alkaline AAA’s: $160
There also is another aspect to consider. Manufacturers still develop devices that do not make proper use of rechargeable batteries and that’s plain wrong. Devices should be designed in a way that they work perfect on rechargeables but can accept Alkaline batteries should you need to. The form factor of the rechargeables (and their Alkaline replacements) may not be perfect, but at least it is standardized. Not so for a whole range of devices (like mobile phones) where even within the product range of a single manufacturers you are faced with a multitude of proprietary rechargeable batteries which cannot be re-used/shared between devices AND device specific chargers. Totally ridiculous. That should be penalized IMHO. How environmental friendly is that? I also want to second another point someone brought up here: The more devices one uses that employ standardized rechargeable batteries, the less significant the charger costs become. We are a 5 head household with so many battery powered devices that I have two charges (one for 4x AA and one for 4x AAA types) running 24/7. Whenever one needs any they are swapped out.
I opted for chargers that take their time charging because my understanding is this is more beneficial to the lifespan of the rechargeables due to the chemical energy storing process being less aggressive and more similar to the discharging pattern (so this might be a misconception of mine). Choosing the slow chargers, however, required some convincing of myself, because recharging cycles of 1hr only just sound very convenient. But when you need batteries, even a 1hr wait for charging is too long. Hence the setup of having two charges filled with rechargeabels all the time. I currently use NiMH. Why? Because I have a whole bunch of them. Once they die out on me, I’ll switch to the next best technology out there then – and probably buy two new suitable charges again.
Where did you get the ridiculous figures you’re using for the cost of NiMH batteries? I have a whole drawer full of the things and I never spent more than $1.50 on any of them (they’re all name brands — Duracell, Rayovac, and Kodak). The Wal-Mart by my house sells 4-packs for $5. The alkalines they sell run about 80 cents each when purchased in the large packages, or about $1 each when purchased in smaller quantity.
I’ve used the same set of NiMH batteries in my wireless keyboard for about 3 or 4 years (8 or 10 charges) and they’ve paid for themselves in that time. I use NiMH in everything except the smoke detectors and I’ve only purchased one package of batteries in the last few years. I’ve got Logitec Harmony remotes which will burn through a set of 4 alkalines in less than 60 days.
The total cost of all my batteries and the charger was around $50. It may have taken a while, but it has definitely paid for itself by now! As long as you get 3 or 4 uses out of each battery the cost is justified except for low drain+constant use items like a wall clock. Do people really leave batteries in things they only use occasionally when not in use? I know I don’t. Unless I use something every day, the only time it has batteries in it is when it’s in use.
I go through batteries like crazy and it just doesn’t make financial sense for me to buy alkaline.
I’m having good luck with Tenergy Nimh AA & AAA batteries at well under $2 each. And you only have to buy the charger once. Sure, they might not work in a clock but I have exactly one clock that needs batteries. I have so many more devices that can use rechargeable batteries – cameras, tv remote controls, xbox and wii controllers, rc toys. Why on earth would I go buy batteries just to throw them away.
Even in low draw applications these rechargeable batteries will still be working long after I throw away 4 sets of alkalines (equal cost wise).
Where do the Sanyo Eneloop batteries fit into this analysis? Are they better? Worse?
Thanks!
I feel I need to correct one area you have commented on, and that’s the proper cell choice for LED flashlights.
Contrary to your assertion in a previous post, most LED flashlights do not ‘pulse the LEDs’. They may employ PWM at lower intensity levels, but on high they must be considered high-current, high-drain devices. Many modern high-brightness LEDs demand more than 1 amp of current in flashlight applications, and will run at a significantly lower brightness if alkalines are used.
Most flashlight hobbyists (and yes, there is such a thing) favor LSD NiMH cells for use in high power lights. They can deliver the high current required, have low self-discharge rates for storage purposes, and perform better at low temperatures than alkalines. NiMH cells also have a flatter discharge curve than alkaline cells, and can provide a form of regulated output in LED lights that do not use a regulation circuit. Additionally, NiMH cells have the benefit of not leaking over time and potentially ruining an expensive light.
@Richard: You are correct about the lower voltages of NiMH. This is also the reason why for devices that require more than 2 or 3 batteries, disposable alkalines (with their higher voltage) are often the best solution.
@Jason: I don’t blame you for using rechargeables in your situation. Just make sure you buy the best charger you can, otherwise you will prematurely age your batteries.
@Erik: The main reason why I selected 8 batteries rather than 5 for the example is that the NiMH rechargeable batteries come in packs of 4 and 8. I do not know if you can even buy them individually and if you could the price would naturally be more expensive anyway.
By the way, it is a fair comparison if the person buying the batteries (me) wants the convenience of always having fresh batteries available as replacements when the other batteries run down.
@CTT: If I used my MP3 player enough, that would certainly be a good candidate. I’d be wary of the charger you have. That price seems to suggest you have a model that charges too quickly – if those batteries are warm to the touch when charging you really should find a better charger.
@Andrew: My $24 price for rechargeable NiMH was based upon the cost for an 8-pak of 2700 mAH PowerEx batteries – arguably the best performing rechargeable NiMH on the market. I’ll wager your price is for the 2000 mAH Eneloop LSD NiMH. And that price is conservative, by the way, as they retail for $30. Of course, comparing the Eneloop to the PowerEx is comparing apples to oranges, but if you are interested I can send you some interesting test results that compared numerous NiMH batteries (mixed bag, LSDs and performance) and I agreed with their conclusion that the PowerEx was the better alternative. Then again, it all comes down to your applications.
BTW, I can get a package of 36 AA Duracel alkaline batteries at Costco for 40 cents a battery.
As for leaving batteries in things that aren’t used over long periods, I prefer to keep my emergency flashlight “loaded” at all times; who wants to look for batteries in a power outage?
@Matthew: In your case, rechargeables seem more than reasonable. I just don’t think your case is typical. Yes, you will eventually get your money back using rechargeables batteries for low-current draw devices – assuming your batteries and/or charger don’t die before the payback period is reached. I have electronic clocks that require a new alkaline battery once every two years. At 40 cents per alkaline, the pay back period is over 6 years away – and that is not even considering the effects of the time value of money.
@Michael: I don’t think Sanyo’s LSD Eneloop batteries are worth it for low-drain devices. From a financial perspective they are by no means any more cost effective than alkalines for the typical household. See my comment to Matthew for just one example.
@Steve: Thanks for the correction – I know better than to argue with the flashlight enthusiasts!
This article might be correct for old NiMH cells, but the conclusion is very wrong once cells like Sanyo Eneloop are considered. They self discharge only 15% per year, which means they are completely suitable for all but the lowest current applications. Since buying Eneloops, I have not purchased an alkaline AA cell in over a year. The only item still with alkaline is my TV remote. Flashlights, video-game controllers, digital cameras, and more are all on Eneloops and work great. I have never paid more than about $2 per cell.
Eneloops don’t have have the 2700mA capacity of the cells used for comparison. They are only 2000mA/hrs but they are still superior because of the low self discharge. Before these cells, NiMH were unusable in most cases because after you charged them, and they sat for a while, you couldn’t be sure they were still full.
The “low voltage” knock on NiMH is often not valid because NiMH (both Eneloop and older types) cells have lower resistance than alkaline, so even though the open circuit voltage is lower, the cell voltage doesn’t drop as much when it gets hit with a load. This is why NiMH have always worked better than alkaline AAs in digital cameras. Alkalines drop a LOT when the flash recharges, and trigger the “dead battery” indicator.
I strongly implore readers to get a pack of Eneloops and a charger and stop filling the garbage with alkaline AAs. I am talking from direct personal experience. These cells work. Len is WAY off base.
Great info, but as in the case of car ownership (not very cost-effective if public transport is available) once the decision has been made to purchase a good charger the equation changes, and that should be explored.
I do a fair amount of photography and in flash units rechargeables (NiCads esp.) make more sense economically. Since I already have a sophisticated, multi-battery charger, my criteria for deciding what to use rechargeables in negates the cost of the charger.
That being said, about the only other things I do use the rechargeables in is a wireless keyboard and some wireless speakers. I buy no-name AA and AAA alkalines in bulk (but have yet to find D cells). For low-temp use, lithium batteries work well but are not available in all sizes.
I also tend to use alkalines in safety equipment like smoke detectors. As I replace the batteries before failure on a yearly cycle, I’m not sure how long NiMH cells would last, but the bother and possible risk are not worth it, IMHO.
@lens142: The conclusion of the article is that the batteries are rarely cost effective. Even if the NiMHs are LSD, the payback period is far too long to justify the expense of converting from cheaper alkalines. I stand by that assessment.
@CanAm: Yes, if you ignore the cost of purchasing the charger then the equation changes, but why change the equation? The purchase price of the charger must be considered in the analysis.
Thanks to both of you for your comments.
Except when you forget about them and the alkalines LEAK!!!
Ruined lots of remotes this way.
This article only works if you look at a payback of 18 months. My oldest rechargeables are approaching five years old and are used in everything from kids toys (low to moderate draw/use) to keyboards and mice to commuter bike lights (high draw, daily use). I don’t know if cycling them through a variety of applications matters, but in my case I haven’t bought a battery or charger in over three years.
What about all those normal batteries that end up in landfills – did you add that to your costing?
You have some good points. There are uses for alkalines and there are uses for rechargeables. I don’t think it is fair to only use the retail price of NiMH’s and then to use the “on sale” price of alkalines to make your cost comparison. Either use retail price of both or on sale price of both. Also, 18 months for the wireless mouse seems arbitrary. It seems like you would use it for 3 years (and even then might replace it with another one that also uses batteries) and for the second 18 months the rechargeables are free.
I agree on buying a good charger, though you can get a good charger for $25 (on sale or at Amazon) that will 1. charge batteries individually instead of in pairs, 2. charge batteries at the non-damaging rate of 1-2 hours, 3. cut off when the battery is full. The $40 chargers are more versatile, but might be overkill. However, it is almost impossible to find good chargers in stores.
Lastly, I think low self-discharge batteries can change things. They will be ready when you pick up the digital camera or flashlight after three months or a year since the last time you used it and you can take more pictures or shine the light longer than with alkalines. And they won’t corrode like alkalines that sit around for too long. If you get them on sale, you can stretch the 3-month cycle you talk about to 6-9 months and still be economical. LSD cells can be recharged thousands of times when using a good charger. And they will easily last 5 years or more.
@Steve: I don’t quite understand your first sentence. The payback period is not the variable here. It is determined based upon the costs of the respective batteries being compared. What I think you are trying to say is that if your batteries AND battery charger last long enough then you will eventually get your money back. That is the basic conclusion of my article, so I think we are in agreement. The questions you have to ask yourself are: 1) are you willing to wait five or six years to get your payback, and 2) how confident are you that your batteries and charger both last that long?
@Dax: Remember,near the top of the article I said those who use rechargeable batteries for environmental reasons was understandable. But the environmental costs of batteries ending up in landfills were not considered because they are irrelevant for the purpose of this article. Just as all of the costs related to driving to the store to buy the batteries, manufacturing and other ancillary costs were not considered. Then again, even if I did, I suspect it wouldn’t change the outcome.
@Ted: Thanks for the great comments! No question NiMH LSDs are good batteries that have their advantages – but for me I don’t think its worth waiting five or six years to realize the payback. There is just to many things that an happen over that period that makes it not worth the risk for me. A couple of clarifications: I did not use the retail price for the NiMH batteries I suggested; I backed off the suggested list price by approximately 20%. Also, the 18-month period for the wireless mouse is simply the amount of time I have owned my wireless mouse. Of course, the longer you own your rechargeable batteries, the more cost effective it becomes – which is what I said in my article.
You haven’t mentioned the Kid factor yet.
If you have kids, rechargeables gain a huge advantage. They will find your flashlights and leave them on, play their toys for hours (and then leave them on), Jam the remote under a toy (leaving it on) and generally use up batteries much more quickly than normal humans are capable of.
Then once you’ve got the charger to take care of that, throwing a rechargeable in the wall clock isn’t as bad of a deal (you might even have an extra if the toys don’t require a multiple of 4).
–
Anecdotally , we bought a NiMH charger and an assortment of rechargeable AA, AAA C and D sized batteries. The AAs are finally dying this year. They will power kids toys for a few days, but will no longer power my wife’s camera’s flash. I feel like we got our money’s worth, and am getting ready to buy new batteries come January.
AUGH! I meant to say that we bought the batteries 5 years ago.
Sorry, but I see this kind of sensationalist writing as extremely short-sighted!!
(And by this, I mean the title!!)
There is a lot of good information in the article, but someone will just look at the title and say: ‘Hey, I don’t need to buy rechargeables!’
You were lucky with your wireless mouse (and battery!) My cousin used up A LOT of batteries in less than one year!! Before we talked and I told them that rechargeable batteries exist! /sigh/
Also, who plans to live just for one year? Maybe add ‘for terminally ill with cancer’ in the title?
Everyone plans to have rechargeable batteries for a long time, and we are very happy with ours, and have had them for years!
And those ‘environmental reasons’ are not just ‘environmental’ – we are talking about human health!!
Have you ever lived near a landfill or incinerator? Great health risks are imposed on people living near by, toxic-laden water or air can travel far too – and throwing trash in landfills ‘because it’s short-term cheaper’ may cost *a lot* of money!!
How much does one cancer cost? Or two?
Those treatments are extremely expensive!!
And if some batteries ‘don’t need special recycling’ it means they’re not AS toxic as others, ideally they would still be recycled, as the landfills are filling up and incinerators are pushed worldwide!
Landfills are basically chemical bombs waiting to happen, often haven’t been planned well enough, fires occur due to methane and the chemical reactions in there are just unpredictable!
I do think it’s sort of irresponsible to even just suggest people can just toss batteries instead. How difficult is it to bring them back to a store and put in a box where they can be properly recycled?
So puh-lease! I would perhaps survive ‘Why rechargeable batteries are not always immediately cost-efective’ but from someone who advertises the blog with ‘believe in personal responsibility’ I would expect more!
With respect, Layla.
Sorry, Layla. Your proposal that I should re-title my article “Why Rechargeable Batteries are Not Always Immediately Cost-Effective” would not be responsible because it is simply not true. As I showed, there are many cases where they are simply NOT guaranteed to be cost effective. As for making this a human health issue, do you apply the same criteria for cars as you do batteries? Rather than a car, do you drive a horse and buggy? After all, automobiles spew far more toxins into the environment (via their batteries and emissions) over their lifetime than a little AA alkaline battery. No? Then puh-lease!
I’m glad, Layla, that you have chosen to go with rechargeable batteries to save the environment and make a stand for better human health – but please don’t ask me to mislead my readers simply to push your particular agenda.
Your argument about cordless mouse batteries and keyboards is flawed because most people already have acharger for their high drain devices. If you already have a charger you can take the $40 cost for the charger out of that equation. Yes most homes have a great many low drain devices but they also have a great many high drain devices. I use rechargeable for 2 cordless mice, 2 cordless keyboards, 3 transisitor radios, 3 digital cameras, bathroom scales, dozens of kids toys, 2 torches, 4 wii rmotes, wii fit balance board and the list goes on. Rechargeable batteries save me several hundred dollars per year not to mention the impact on the environment. Even if your argument is correct (and I strongly disagree that you are) some people do not mind spending more money to save on the environment. Solar panels are agood example. This is one iem that does not stack up in cost effectiveness but people prefer to use them to reduce carbon emmissions. There are only two items in the home I would not use rechargeable batteries in and they are your remote controls that are very low drain and smoke detectors. The reason you should not use them in smoke detectors is not on cost but on safety. Rechargeable batteries when they go flat have a very fast drop off in voltage compared to alkalines that drop off in voltage very slowly. What this means is that when rechargeables go flat it happens fast and if you are out when they go flat you may not hear the warning beeps to warn you the battery has gone flat.
Thank you for your comments, Steven! But I have to tell you, it is your logic that is flawed.
Unless you can somehow conclusively prove it, your opening statement is anecdotal – which completely undermines your argument. And I strongly disagree with your assumption anyway; I’ll wager the vast majority of people don’t use rechargeable batteries – and therefore don’t have chargers – simply because the high up-front costs discourage their use.
Secondly, it doesn’t matter when you buy the charger. You still must use it in your analysis, if you are being honest with yourself.
I realize the environmental benefits of using rechargeable batteries – I stated that in the opening paragraphs – but that does not make my analysis invalid from a personal finance standpoint, which is what it is. The fact that you have made a conscious decision to pay a little more money to use rechargeable batteries in low drain devices to help the environment is noble. It’s just not the best decision from a personal finance perspective.
This is a wonderful article. I must tell you, i was not aware of the kinds of batteries. This article is too knowledgeable and informative for everyone. I think using alkaline batteries and rechargeable batteries intelligently, as explained by you is going to be really cost effective for all.
Thank you, Charger.
I just couldnt leave your website before saying that I really enjoyed the quality information you offer to your visitors… Will be back often to check up on new stuff you post!
“if those batteries are warm to the touch when charging you really should find a better charger”
I have never seen such a charger – ALL the high quality smart chargers I have seen (Maha, Varta etc) heat the batteries – cheap chargers are just slower and actually heat the batteries LESS because of this.
As has been pointed out nearly all NiMH batteries are low drain now so bang goes your low drain argument.
The relative cost of NiMH to Alkaline batteries where I live is about 3:1. I only have to get 4 charges to save money. Not a very long payback.
my remotesx6, camerasx3, mouse, keyboard 2x childrens MP3 players (these would use 1 Alkaline/per day) countless kids toys etc.
Obviously the cost of a charger spread over all these is minimal.
quote”Unless you can somehow conclusively prove it, your opening statement is anecdotal ”
Ummm, can you prove ANY of what your article says?
Are you REALLY an engineer? If so I suggest you do a bit more research before you make a fool of yourself
Well, there you have it, Ian. Speaking of anecdotal arguments, you just made another one – that is, you haven’t seen such a charger so it must not be true.
Seriously, there are plenty of cheap chargers with rapid charge cycles out there that cause the batteries to heat up.
You conveniently leave out the cost of the charger in your payback calculation. I already noted that alkalines make sense for high-drain devices.
And yes, you can conclusively prove what I am saying! There is test data all over the web, including a couple links I included in replies to other commenters.
(PS – There was no need to make this personal, by the way.)
If you’re talking about 4-packs of Duracell rechargeables for $15 at Best Buy, you have a point. But if you’re willing to buy a third party brand in bulk on eBay, you can do very well. A couple years ago I got 80 AAs for $110. I split ‘em with my folks and have been happy with them. Definitely saved money over the 2.5 years I’ve had ‘em.
Ok, so to summarise:
1. The payback time of rechargable batteries is too long (how much, why, how long – it doesn’t matter, Len says so)
2. Most devices in peoples homes are low drain (”"”"Len says so)
3. Despite the fact they are low drain and use very few batteries, most of the batteries you will use will be in low drain devices (ummmm???)
4. It’s uneconomic to buy a charger, they are just too expensive.
5. However, it makes good sense to go out and buy bulk alkaline batteries… for the ..low drain devices that use almost…. no batteries?????
6. High quality NiMH battery chargers only slightly warm NiMH batteries, if they get any hotter It’ll ruin them(those 10 year old 1600mAh Powerex NiMH which get scalding hot in my crappy MH-C20F Maha charger are a figment of my imagination)
7. Please everyone, go to your cordless phone and hurl those useless NiMH batteries out the window – NOW.
1. There is no set answer, Ian. As I explained to a less, um, emotional reader, my payback period was 6 years. Notice I said “MY” period. Everybody’s paybacks will depend on their own circumstances. I also gave an example of the payback when it came to my wireless mice and keyboards. And the article says “rarely” cost effective – not “never.”
LOL
2. I said in a “typical” home. I stand by that statement, Ian.
3. Don’t you think? If, say 90% of the batteries in a home are low-drain, doesn’t common sense dictate that most of the batteries you use would be in low-drain devices? Ummmm? Of course, there may be instances where you have a Wii, for example, where the number of batteries used there WOULD overwhelm the number of other batts used on low-drain devices. That’s how it is in my home – and guess what? As I stated in the article – I use rechargeable batteries for them! You seem to have missed that major point.
4. That is often the case, Ian. Everyone has to run their own numbers.
5. Of course it makes economical sense to buy them in bulk – depending on how many low-drain devices many homes will still need to make quite a few replacements.
6. High-quality chargers do no harm to rechargeables. What’s your point? On second thought, never mind. I think your batteries are starting to overheat.
7. Wow. You are getting way too emotional on this subject, Ian.
Thanks for airing your opinions.
I have several Energizer NIMH rechargeable batteries that have not been used in some time. They are maybe 2 years old, used rarely, and never left in devices (always removed). I recently bought a new camera that can take AA batteries. I plugged in 3 batteries in the 4-slot Energizer recharger. Two charged, the third did not. They were not removed until the green light indicator came on. The 2 that charged showed a “good charge” on my battery tester. I put them in the camera and it showed low battery and would not operate. I took them back out to retest them and it still showed “good charge” on both of them. Plus, I have read to remove rechargeable batteries from the recharger when done. So, a person is expected to know how many hours it takes for a battery to recharge? And, make sure they are home to remove them? And, how do you know if you should replace a rechargeable battery? How do I know if it is my camera’s problem or the batteries? The battery for this camera is $10 if I buy the camera battery. I just bought some Energizer Ultimate Lithiums to try in it. I had so hoped the rechargeable ones would work.
Thank you, Teresa
I understand your point of view, but generally disagree. More and more, households are purchasing items which have moderate-high drain: digital cameras(ESPECIALLY with flash); game console controllers(many times 2x AA alkalines will only last a moderate gamer days rather than weeks or months); portable DVD players; MP3 players; etc etc etc. I’d be willing to admit that rechargeable batteries are not financially the best option for everybody. In a rapidly increasing number of cases though, I think the financial viability of using rechargeable batteries is there.
There is also the convenience factor. You say its more convenient to buy a whole whack of batteries in bulk, but really, how many people ACTUALLY do that? Almost everyone I know who is still stuck on alkalines buys a pack of 4 or 8 when one of their devices runs out, then is back in the store a month later buying another pack to replace other batteries.
I’m in agreement with many of the arguments regarding disposable batteries, but find alkaline manganese zinc batteries the poorest choice among disposables. I would not find button cell rechargeables useful at all with the much higher capacity and high quality lithium and silver oxide cells available. I use disposable lithium transistor batteries in my smoke detectors because they don’t seem to leak. I won’t use any Duracell products because they have leaked on me more than any other brand. Putting a set of Duracells into an expensive LED flashlight and then ruining the device because of leakage is hardly cost effective. They do warranty the battery against leakage, but it is quite inconvenient and even then they will try to get out of repairing the item stating that the batteries were stored inappropriately in the device. I grew tired of ruining my lights and my remotes with disposable alkaline cells. The cost of purchasing my AccuPower LSD AAA, AA, C, and D cells was more than worth it just for this reason alone. I stick them in my flashlights and remotes and don’t worry about leakage. I simply recharge the cells once a year. I would never trust my Logitech Harmony remote to any alkaline cell. It’s just too expensive to trust to a cell with tendencies to leak.
Len, THANK YOU FOR REMOVING ANOTHER THING TO FEEL GUILTY ABOUT!! I’m not going to analyze anything you said but just take it at FACE VALUE and save myself some time!! Every time I buy new batteries I feel guilty for not having a whole set up for rechargable ones! As of NOW, I’m going to drop that guilt trip!!
Thanks,
.-= Barbara Friedberg´s last blog ..50 Habits to Increase Wealth =-.
Glad I could help, Barbara!
Your post is a breath of fresh air compared to the usual rubbish I learn on solar power. There’s a lot of scams available. Thank you for helping me out.
Wow, how emotional people get debating the pros and cons of batteries! I actually ran across this site looking for info on charging batteries from the sun. Let me tell you, halfway through a solar project (after the solar panel, charge controller, and inverter was purchased), solar power is NOT a way to save money short term. It’s expensive. But if it saves some money in the long run, great. Either way, it gives me the peace of mind of knowing that even if the power fails again, I can charge my laptop, cell phone, etc. I look at rechargable batteries the same way. Not a perfect solution, perhaps, but something to fall back on if I’m out of fresh batteries. And it’s fun. You won’t save money with either solar or rechargables, but it’s fun.
.-= Harvey Flea´s last blog ..Yuri Tackles Tax Time =-.
I have visited your blog before. The more I visit, the more I keep coming back! ;-P
You can never go wrong with Sanyo Eneloop batteries, they have very low self-discharge rate and it is a bang for the product.~*.
I agree with you, Rechargeable Batteries are not always cost effective. That is the reason I never use these batteries in my wall clock and alarm clock. You have mentioned useful recommendations here on using rechargeable batteries wisely to be benefited.
So, no kids?
Most of their toys would be classified as high-drain devices.
Rechargeable LSD NiMH AAs are cost-effective for those.
And even eneloops only cost $2 on sale.
As I mentioned in the article, Bill, I do have kids and they absolutely have high-drain devices that I buy rechargeable batteries for.
oops!
let me recommend the lithium AA for those applications that are critical (grab some battery size adapters and never have to purchase C cells again)
I had too many alkaline batteries leak even when stored in conditioned space – lost many flashlights that way before switching to lithium AAs (about $1.25 delivered via ebay) for critical stuff like emergency flashlight/radio
Len, When I first saw the title, I thought this was an article from 2004. While I agree on the whole “low draw” wall clock argument, in this day and age, no one is concerned with those types of devices in our homes. Throw some alkalines in them, and move on. Problem solved. Now… on to everything else in my house that I’m constantly scrambling to find batteries for, month after month – that are constantly eating up batteries. To make the claim – Why Rechargeable Batteries are “rarely” Cost effective… are you kidding me?
99% of everything in my house that truly counts are high draw devices (cameras, toys, video game controllers). Any akaline batteries I’ve ever bought in bulk have been quickly used up in these types of devices. And about the added up front cost…I bought a Rayovac charger and rechargeable batteries over 8 years ago that I’m still using today for most of these applications. This doesn’t even take into account the new Hybrid technology that is superior to my rechargeable batteries. To sum up, I don’t disagree so much with a very few of your specific points…it’s the title of your report that I personally find ridiculous. Talk to anyone with kids, and bring up “batteries” – trust me, they’re not worried about their clocks and thermostat. I think a more fitting title in my opinion would be “The few instances when rechargeable batteries are less cost effective than alkaline.
Thanks for chiming in, Darin. (No pun intended. Well, okay, yes it was.) LOL I would be careful assuming “no one” is concerned with low draw devices in our homes. Clearly, the guy ahead of me in line who was replacing every single alkaline battery in his home was.
I also wouldn’t assume that 99% of electronics in everybody’s homes are high drain devices because that’s how it is in your home. Let’s look at common low drain devices:
1) Remote controls
2) Clocks
3) Smoke alarms
4) Flashlights
5) Radios
By comparison, lets look at some common, and not so common, high drain devices:
1) Cameras
2) Portable Disc Players
3) Hand-held Games
4) Remote control toys
5) Game console remotes (wii’s)
6) Boom boxes
7) Hand held TVs
Maybe I am all wet on this, but I’ll argue that the majority of all homes have most or all of the items in the first list (low drain devices). Not so for the second list (high drain items) – especially for homes where the average age is over 50 and/or there are no kids in the home.
Waw, amazing blog. And still going on…
I live in Europe and I was looking for a few sets of LSD batterys when I found this article.
I have been using cheap rechargeable batteries at about 3$ for a set of 4 NiMH AA’s 2400 mAh for more than 5 years. At this time they are so cheap it is as cheap as a set of Alcalines. 1:1.
The only drawback is the self discharge and this is why I do use Alcalines in remotes and clocks. But that’s about it.
The new LSD batteries are more expensive, but there is no drawback. Up to anyone to consider if it is worth it, but for all uses but remotes, thermostats, clocks and perhaps low-cost LED lamps, a rechargeable battery is more cost effective.
Yes, I have more low draining devices but that is why they don’t need as much batteries. If you have 5 remotes, you probably need about 10 alcalines every two years. If you have one digital camera running on AA’s, you would probably need two AA’s every month, which is much more even this is only one high drain device.
So the artickle is somehow misleading !
may friend had a china made battery charger and it overheated after a week.
Hi, I work for a company called PC Treasures, and we offer a charger that I think is very cost effective. It’s called the ReZap Battery Engineer. Check it out at digitaltreasures.com.
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