Introduction: What Battery Brand Provides Power the Longest?

Picture of What Battery Brand Provides Power the Longest?

In this age of ubiquitous electronics, batteries have an astounding importance in our everyday lives. As we buy and use different brands, we come to wonder, "Which of these is actually the best? Is it worth it to go for a big name brand?" To answer these questions, I set up an experiment to test the endurance of four different battery brands: Duracell, Energizer, Rayovac, and Sunbeam(a dollar store brand).

Step 1: The Materials and the Hypothesis

Picture of The Materials and the Hypothesis

To test the comparative endurance of the four battery brands under study, I used four Mini Maglite xenon lamp flashlights purchased from Walmart on the same day. As for batteries, I bought an eight pack of Energizer AA batteries, an eight pack of Rayovac AA batteries, and a four pack of Sunbeam dollar store AA batteries. The flashlights came with Duracell, so I used those batteries for the Duracell test. I did, however, find a price for a Duracell eight pack in order to compare prices more effectively in the conclusion.

My hypothesis was as follows: Dollar store batteries will be the first to go, with one of the bigger name brands coming out on top. I had no basis for distinguishing between the three top brands, but because the Duracells came with the flashlights, indicating that they might be preferable, I hypothesized that Duracell would last the longest.

Step 2: The Setup

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To carry out the actual test, I prepared an apparatus that would hold the flashlights parallel to one another, all shining on one piece of cardboard so their relative intensities could be observed. I put two Sunbeam batteries in the top light, two Duracells in the second, two Energizers in the third, and two Rayovacs in the fourth.

Step 3: Starting the Test

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To start the flashlights, I went from top to bottom, twisting the top of each light until the exact point at which the light turned on (the flashlights were turn-top instead of push-button. Button flashlights may be more useful in future experiments). In all, going from Sunbeam to Duracell to Energizer to Rayovac took 13 seconds.

Step 4: After 1 Hour

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After one hour, all four lights were shining brightly, with no apparent difference in intensity from one brand to another.

Step 5: After 2 Hours

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After two hours, the relative brightness of each light remained pretty much the same.

Step 6: After 3 Hours

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After three hours of constant shining, still no significant change.

Step 7: After 4 Hours

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Here's where things started to get interesting. After four hours of shining, all four lights were still lit, but Sunbeam (the dollar store brand) was starting to show slight signs of weakness.

Step 8: After 5 Hours

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The Sunbeam was, indeed, the first brand to fail, providing no more light at precisely 4 hours and 50 minutes. The five hour picture shows the three remaining brands, with Energizer starting to look a little bit dim.

Step 9: Sunbeam Bulb Test

Picture of Sunbeam Bulb Test

In order to determine that the failing of each flashlight was due to the batteries dying and not the bulbs burning out, I took out the batteries from the dead flashlight and replaced them with fresh Duracells. The results show that the bulb still worked quite well, verifying that the batteries' losing power was the reason for the light going out.

Step 10: At 5 Hours and 9 Minutes

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I interrupted the regularly scheduled hour-increments because Energizer seemed quite close to going dead. I prepared for a picture at five and a quarter hours, but took this picture at 5h 09m to show the dimming Energizer.

Step 11: At 5 Hours and 15 Minutes

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By the time 5h15m finally rolled around, Energizer was fully depleted.

Step 12: Energizer Bulb Test

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As I did with the Sunbeam light, I took out the Energizer batteries and replaced them with fresh Duracells to check on the working status of the bulb. It's function was still maximal.

Step 13: After 6 Hours

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After six hours, even the strongest two brands were significantly dimmed, with Duracell a good bit dimmer than Rayovac.

Step 14: After 6 Hours and 5 Minutes

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At 6h5m, the Duracell batteries were pushing out the very last bit of power they could muster, showing a bright spot a fraction of the size of the beam cast by the Rayovac-powered light. It is worth noting here that the Duracell flashlight seemed to take longer to fully go out than the others, remaining persistently dim for an extended period of time, finally going out by 6h10m.

Step 15: Duracell Bulb Test

Picture of Duracell Bulb Test

In the time it took me to prepare the Duracell flashlight for the bulb test, the Rayovac light was significantly dimmed. The Duracell bulb performed well with fresh batteries, just as those before it.

Step 16: After 6 Hours and 12 Minutes

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Rayovac was the last flashlight to go out, dying at 6h12m.

Step 17: Rayovac Bulb Test

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Finally, I performed the switch from spent Rayovac to fresh Duracell for the last flashlight, demonstrating the continued effectiveness of the Rayovac flashlight's bulb.

Step 18: Conclusions - and the Winner Is...

Observing the times of battery death for the four tested brands, the results are as follows:

1-Sunbeam = 4h50m

2-Energizer = 5h19m

3-Duracell = 6h10m

4-Rayovac = 6h12m

As hypothesized, the dollar store brand was the first to die, and contrary to the hypothesis, Rayovac lasted the longest shining time, beating Duracell by only a couple of minutes.

Dividing the price of the battery pack by the number of batteries in each pack, I calculated the price per battery for each brand:

Sunbeam = $0.25/battery

Energizer = $0.79/battery

Duracell = $0.80/battery

Rayovac = $0.62/battery

Dividing the price of two batteries by the time during which they provided power gets the price per hour of battery power.

Sunbeam = 10 cents/hr

Energizer = 30 cents/hr

Duracell = 26 cents/hr

Rayovac = 20 cents/hr

Based on these results, Sunbeam batteries provide the most power for their price. However, as they provide power for the shortest time, the necessity of frequent battery changes may decrease the value of the batteries in terms of convenience. I would argue that Rayovacs are the best buy because they provide power for the longest time with a comparitively low price, even if they only come in second on the price/power lineup.

Step 19: Worth a Note:

While the results of the experiment are clear, interpreting them can only go so far. The batteries may perform differently in different devices, and the relative duration of power supply may differ if the flashlights are turned off for a period of time and then turned back on. For each light, after going out, turning off the light and turning it back on a few seconds later would yield a small beam of light, although this beam only lasted a short time before going out again. These factors would be an interesting topic of study for future experiments.

Thanks for reading!

Step 20: Contest

If you haven't already, please vote for my experiment in the Scientific Method Contest! I really appreciate all of the compliments and suggestions from everyone who's already viewed - if you could help me out in the contest, I would be very grateful!


Lorax98 (author)2014-05-20

You have not only determined the value of various battery brands, you have also given an A+ demonstration of the scientific method!! I will be using your Instructable as an exemplar for my grade 9 science students.

DIYnosaur (author)Lorax982014-05-20

Wow, thank you very much for the compliment -- I am quite honored that my project can be used as an educational tool!

osh114 (author)2014-05-18

I find this experiment very educational and very helpful for all. This experiment is worth my vote because it not only is simple but it is very practical for all that read it. Great job and keep up the good work!

Bill WW (author)2014-05-16

Nice work, great test!

Yes you could do all those things suggested in the comments. But your test is fine as it is. You explained the limitations.

I have done the current draw test with large 12v boat batteries, plotted charts, made comparisons. You can drive yourself crazy measuring, considering all kinds of variables. What you did was very clear and concise.

DIYnosaur (author)Bill WW2014-05-17

Thank you very much for the compliment and the comment! I know what you mean by all of the tests driving you crazy - just thinking about all of the possiblities and variables was enough to boggle my mind.

ADG1 (author)2017-04-30

I find this test inconclusive and lacking detail. First of all the kind of battery was not specified. Sunbeam at the 99 Cent or dollar stores provide three types of batteries, regular, alkaline and heavy duty.. Lately a New one has surfaced .. AC DELCO Alkalines .... And since you didn't specified which types of AA they are, and that they are all the same types, your test means nothing to the smarter people in the world. I use Dollar Store Batteries on my LED< and they last more than 5 hours.. YOu also, need to compare the expiration dates they are all in the same range. If I pick up some that are a couple years apart, the test is not valid.. I am tech and shelf affects all batteries. Theoretically. capacitors are supposed to hold a charge forever, when not discharged but they don't.. Now if you said they were all Heavy DUty or something like that and they all expired in about a year and all brands use the same time for expiration after manufacturing them, then I say the test is conclusive. So your test was nice, it is not a good test, as dollar brands may be there because the shelf life is about to expire...

SteveL234 (author)ADG12017-05-24

Although you have a valid point, there are also pictures as part of this Instructables article -- if you take a close look you'll notice that the type of Sunbeam batteries are in fact the alkaline type. The Heavy Duty ones are not that color. I agree that the scientific method needs to be followed, but this is an instructables website. This is not a peer-reviewed academic journal.

Emile parker (author)2017-01-10

i like this kinda project

Von LesterG (author)2016-09-30

thanks.., Now I know what to buy.

RobertG239 (author)2016-08-01

Hey, Congrats on first prize! You deserve it! This test was done perfectly.

DestinyM10 (author)2016-04-25

So what would you recommend for a motor. I'm doing an experiment on making a Lego car and trying to see which brand of AA battery's makes or helps the motor run the fastest. Duracell or Energizer?

Please get back to me as soon as you can!

TessaS5 (author)2016-01-27

What a fantastic project. Great scientific method and a well thought out and well carried out project. I am definitely going to show this to my grade 9 expo students who want to test a similar idea.

darrenah (author)2016-01-20

Thank you for doing this. This is very helpful information to know!

Yonatan24 (author)2015-12-04

If you want to help save the environment, Go with Sunbeam
If you want to carry less batteries, Go with Rayovac

DeniseS45 (author)2015-11-27

Thanks for your experiment! Based on the results of your test I've decided to use the cheaper brand in my label maker and in other electronics where the batteries are easy and convenient to change, and I'll use the longer-lasting, more-expensive brand in my alarm clocks, remote controls, or in anything else where I think longevity beats cost. I'm glad I checked this out before I placed my order on Amazon, so thanks again! :)

daxap (author)2015-11-18

Great project and it helped on my science project

Zxcv6789 (author)2015-11-10


imark77 (author)2015-06-22

I would love to see Panasonic ( alternate dollar store option ) as I've never really trusted Sunbeam. it would also be nice to see the Lowe's house brand ( which I suspect is a rebrand ). RadioShack's ( if you can find one) would also be a good test.

PS did you know that using anything other than Duracell, will void your warranty on those mag-lights. and if you're unlucky enough to have your batteries leak you can get a free mag-light replacement if you had Duracell in it ( discounted if they find you didn't ).

do I trust Duracell's not to leak ***** NO!

lovelyloveme1234 (author)2015-05-14

JavierC9 (author)2015-04-01

Very good experiment. Congratulations!

msteele1 (author)2015-02-28

I had basically the same idea. I bought three single cell LED flashlights to test the life of batteries from different brands to tell which one is the best value. I use a lot of AA batteries in my two cameras and it just seems to me that the store brand Alkaline batteries I had were running out of juice rather prematurely. To save me the trouble of having to monitor the things I set up one of my cameras for timelapse with an interval of 10 minutes for up to 99 exposures (the limit of my camera). The problem I have is not having any idea how long any of them will last. If you can get 6 hours out of two AA alkaline batteries with a regular incandescent bulb (how many watts:?) it would also be interesting to know how many hours you can get out of an LED light source (how many watts:?) and one AA battery. Anyway if they haven't fizzled out by the end of 990 minutes of 16.5 hours I will be surprised. Nice job.

Ja'LeahS (author)2015-02-16
thank you for the project very inspiring deffinetly telling everybody about this site

Ja'LeahS (author)2015-02-16
thank you for the project very inspiring deffinetly telling everybody about this site

LilyM2 (author)2015-02-12

BTW, love your tape

montanacby1 (author)2014-12-03

I happen to be taking a break from my finals and bumped into this site on battery testing. The gentleman jlsmoothash2o is incorrect in wanting to know the mah of the batteries. This test was a test of off the shelf batteries. the kind you see at the grocery store. This testing was totally valid on these batteries. When you go to the grocery store, or wherever, to purchase batteries, you look at the brand and the price, No person is going to look at the mah, let alone what the acronym means. The batteries do not need to all have the same mah for proper testing. You do not get a choice of the mah when purchasing batteries at the store. And more then likely the mah's are the same anyway. Same applies to the battery date, though it is good for reference for the stocker and the store, it does not apply to us. The date of the battery is of no consequences. Since I know about the workings of these types of batteries, the amount of time they have been sitting on the shelf is absolutely meaningless. They do not get weaker by time. Using different stop watches is a little carry way. If we are getting this anal over this test, he should have also done a double blind test. But the points being made are valid, but not applicable because of the nature of the test.

itsfarmingtime (author)2014-11-18

Very well done. It has already been stated that more variables could grant better information. For a quick little should I get name brand vs store brand, this is a great instructable.

TexBoyd (author)2014-10-05

Here is a similar experiment that my physics students did several years ago. The "generic" brands seemed to be new labels on name-brands, and could be grouped together by type. Quoting from the article: "We found in that study that the data indicated that there were only about 4 different sources of the batteries identified by their graphs of energy discharge vs. time, with the main difference being that the more expensive brands seemed to have tighter quality control, namely the cheaper brands seemed to have some early failures, while the premium brands did not." The article: Science Projects for K-12 Students

Robibame (author)2014-08-15

awesome instructable.

Teachable (author)2014-07-12

Nice. I buy Rayovacs but thought they probably weren't as comparable as they claim they are to the more expensive brands, nice surprise.

zoomtronic1 (author)2014-06-11


bryanep (author)2014-06-07

Loved it Thanks!

jlsmoothash2o (author)2014-05-21

I see some really big problems with your test.

1 what was the mAh of your batteries. Different Amps values will change the outcome of your test. They need to all have the same mAh.

2 Manufacturing date of the batteries. The longer they stay on the shelf the more power loss they will have. Batteries will give you an expiration date some will give you the date they were made. But if you use the expiration date make sure it is the same month and year. This way you know that they were more than likely made close to the same date or at least they have the same life left in them.

3 I would have used 4 different stopwatches so each one has its own time running this way you do not have to worry about the time from the first one on to the last one on time.

mkanoap (author)jlsmoothash2o2014-05-21

It could be argued that variations in mAhs was what diynosaur was testing.

jlsmoothash2o (author)mkanoap2014-05-21

From what I understood from his statement was he was looking for the best quality of battery for the price. So if your going to do that then you really need to have the same mAh on all the batteries. The reason is if the dollar store batteries were of a lower mAh then the name brand batteries it is not a fair comparison. I know that each of the name brand batteries he listed sell them in different mAh. Each mAh rating has a different price point. Which is why you really need to have the same mAh rating.

mkanoap (author)jlsmoothash2o2014-05-21

But note the step where he divided each one by the time it actually ran. If you assume that each flashlight bulb has an identical resistance and given that the voltage should be the same, and thus that the draw on each battery is identical, than the rate of drain (milliamps) is identical. So by dividing the price by the time it ran, he is measuring how much it costs per hour at a fixed rate. i.e. the cost per milliamp, per hour, otherwise known as the cost per mAh, without having to trust what the manufacturer claims. If you did have them all be the same mAh rating, and if the ratings really were right, then all the batteries would run down at the same time. And then you would just need to look at the price to know. The only value in having all the mAh ratings be the same would be to prove if any of the manufacturers were wrong/lying.

Jerz (author)mkanoap2014-06-01

A batteries capacity vs output isn't perfectly linear as it is scaled up. A 2400mAh battery will usually perform more than twice as long as a 1200mAh battery on certain loads. I think that's the point that jlsmoothash2o was trying to make. As the load gets closer to the batteries rated output, its' efficiency changes in a non-linear fashion.

mkanoap (author)Jerz2014-06-02

That's a good point. But still, in the end of the experiment, DIYnosaur ranked the batteries by cost per hour of useable light. Thus empirically cutting right to the actual cost of powering these flashlight with different batteries. Ignoring of course all the costs of having to lug all the extra batteries around or to change them when the grue is closing in.

Starting with all batteries with the same Mah rating (if you could find them) would be an interesting experiment, but not a requirement for learning what was learned. So I do not thing there were "big problems" with the test.

I guess it depends on what you think the test was determining.

It is true that if you ran the same experiment with different loads, you might find that other batteries are more cost effective for a particular job.

aseavey (author)2014-05-25

very nice test. I did this for a middle school science fair project. using Duracell rayovac and energizer. my test was only slightly diffent as I had 3 flash lights for each brand. and I myself got the same results. all my batteries were produced approx the same time frame from what I could tell by the expiration date. this test was almost 10-12 years ago but none the less nice to see the results are still the same.

shellyscorner (author)2014-05-22

Hey! You did a GREAT job! Honestly, I'm actually not even surprised at the results. And FOR ALL the "ARM-CHAIR QUARTER BACKS" with ALL the suggestions of how the test should be redone and ALL the things that SHOULD have been considered ..... How about all of YOU guys "RE-doing" the test and let the rest of us know how it turns out! Well done and well documented!

lifeinbeats (author)2014-05-22

I agree with others that there needs to be more of a sampling. There are quite a few variables here. Age of battery, quality control of battery company and differences in flashlights pop into my head. It'd be interesting if you were to do this several more times, buying new batteries (all with the same date), and switch up which flashlight contains which battery. That should rule out all of the variables I mentioned above.

SIRJAMES09 (author)2014-05-22


very educational, & very enjoyable read!

TY for posting this & TY for all the work it took to make this. :)

samuraijack (author)2014-05-22

really informative and very well executed.

bravo my friend.

Radicalone (author)2014-05-22

Great job!

nehmo (author)2014-05-21

What chemistry was the Sunbeam? It appears the others were Alkaline, and the sunbeam was Zinc/Carbon in an Alkaline labeled wrapper. Considering Sunbeam doesn't really make them, I wouldn't be surprised. Someone please cut them open and post the results.

The test only used one type of load, a constant resistance of one level. There is much more to Battery comparison than that. Shelf life is also a consideration, for one thing.

khearn (author)2014-05-21

I agree with jlambert that using the Duracells that came with the flashlights might not have been a good idea. They may be older, given the extra steps in their distribution. Plus, it wouldn't surprise me if the batteries distributed with flashlights are different than the batteries sold separately. I know that the ink cartridges that come with most printers have significantly less ink than cartridges that are sold separately. They may also sell lower capacity batteries in bundles to keep prices down. I don't know that they do, but it would be worth testing.

cyberdove (author)2014-05-21

Did all the batteries have the same expiration date?

patsheldon (author)2014-05-21

Nice, thanks for the money saving tip!!

jobard (author)2014-05-21

I have a question. Did you consider the expiration date of each battery? If for instance Sunbeam will expire in Aug.2017 and Energizer in Jun.2019, then, theoretically the latter will last longer.

dropkick (author)2014-05-20

Great Instructable. Thank you for doing this work and providing us with the information.

cybercapri (author)2014-05-20

Well done and the winner was a shocker, won't say who won and spoil the surprise, but it changed my mind... I voted for you and hope you win...

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