# What Battery Brand Provides Power the Longest?

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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).

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## Step 1: 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

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

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

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

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

## Step 6: After 3 Hours

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

## Step 7: After 4 Hours

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

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

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

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

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

## Step 12: Energizer Bulb Test

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

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

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

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

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

## Step 17: Rayovac Bulb Test

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.

## 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!

Third Prize in the
Scientific Method Contest

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## 134 Discussions

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.

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

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!

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.

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.

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...

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.

thanks.., Now I know what to buy.

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

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!

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.

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

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

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! :)

Great project and it helped on my science project

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!