This instructable will tell you how to increase the life of electronics without the need to buy batteries that are expensive and designed to last long.

These are ideas that I am making up as I write this instructable. Please correct me on anything that, well, needs correcting! This is only my second instructable, so I would like any advice on improvements (my first and second instructables were whack and they didn't really even work, cause I didn't test it until after i wrote the instructables, and I abandoned them due to huge flaws). This one will be much better, I hope. Besides, I'm only 13 years old, so I sometimes make very odd creations that never work. :)

Please suggest information for me to add to this Instructable if you believe there is one you think is good. I will select good ones and I will add them to this Instructable.

Using Rechargeables: Several commenters suggested the idea of using rechargeable batteries because usage over time just saves waste and will be cheaper overall to use these over time. So I think rechargeable batteries are the way to go. Read more in the Going Green Section.

JUST A MESSAGE: Wow, I wrote this instructable on August 19th. I was planning on entering it in the Burning questions contest, but I missed the cutoff date by 2 days. After I finished, my computer's power supply failed, so I needed to get a replacement and ordered one. I continued about an hour later with a different computer and when I was going to enter it, I noticed I missed the cutoff date..... For Burning Questions Round 6, there should be one on "How to get good luck", because mine sometimes stinks really badly. Oh well, please take a look at my Instructable and see if anything is here that can help you. I may have missed the contest, but I still had the fun of making an Instructable!!!!!

Step 1: Media Players (like iPod, Zune, and other) and Pocket PCs (non-cellular)

Well, the first thing to do that can increase battery life for iPods, Zunes, and other ones with the LCD screens like those, is to lower the brightness, when not necessary. For example, you do not need to set the brightness to 100% in a dark room. Lower the brightness so that you can still see the screen without strain. Mine is set to 30%, while they usually ship with 50%.

Another option also has to do with the screen. Set the amount of time that the screen stays on to a shorter time. Personally, I don't think anyone should need to have the backlight stay on for more than 10 seconds after you stop interfacing with it. My iPod is set to 2 seconds.

For the iPod Touch, turn off the WiFi when not in use.

I'm pretty sure the same principles apply to Zunes and other players. I don't have them, so I can't really show anything.

Note: The pictures suck because, well, the iPod Nano's screen is very VERY small.
Another powersaver is the joule thief, a device that gets the last bits of juice (down to 0.35V) out of a battery to light a LED for weeks from a 'dead' battery. You can even recharge other batteries with it!
 charge dead rechargeable batteries  or they will die completely 
Alkaline produces 1.5v open circuit when new but has higher internal resistance. &nbsp;NiMh or NiCad has very low internal resistance. &nbsp;This means even through your new 1.5v battery when it sees a load will drop to a certain point. &nbsp;The volt drop goes to heating up the battery itself, and not running the load. &nbsp;Then Alkaline's open circuit&nbsp; voltage drops gradually as it is discharged as well.&nbsp; While NiMh and NiCad stay at 1.2 most of the time, then drop when only less than 1 percent capacity is remaining.<br /> <br /> The capacity of Alkaline varies greatly depending on load. &nbsp;An ideal very low drain Alkaline has about 3000mah. &nbsp;At high drain, you might see only 600mah. &nbsp;The rest of the capacity goes to warming the batteries themselves. &nbsp; NiMh and NiCad has very low internal resistance, so that you don't see a big capacity variation in typical loads found in normal use.
Few more things to test out : When reception is restricted (like in concrete buildings) phone may use more power for transmission. Using and keeping it near the window and / or with the antenna pulled out may enhance battery Screen contrast may affect battery Screen backlight color may affect battery (different efficiency of different color LEDs) All whats applicable for notebook computers is applicable here too Most important : Enjoy life not the phone ! Second hand Nokia 5110 owner. Charging once in 1.5 weeks
you're right about reception... when it's constantly looking for a signal, it's using more power. but the contrast and color of the screen does not affect power usage. the backlight doesn't change color, the screen does. the only way to save energy with the backlight is to simply decrease brightness when you don't need as much. and the screen is not LEDs, it's an LCD. it will use the same amount of juice no matter what color or contrast it is.
the backlight of the screen is LEDs. there are phones with black and white screen and colored backlight which can be changed in the settings
the backlight isn't always led's. led backlights in laptops is just starting to emerge. besides, how do you know it isn't a filter? and if it is led's, i bet that the color is from a combination of different colored led's... meaning, even if you chose red (the lowest frequency and therefore the lowest power usage), it wouldn't be simply red... it would be a combination of led's making a red color, because it would be nearly impossible to see the screen with a normal red led. i just don't think it's very likely at all. if this was the case, then the difference in battery life would be enormous by switching to a red screen. most led colors use more than twice as much power as red.
it'd be the other way then - that blue is the most efficient blue led voltage is higher so it needs less current (smaller resistor) to get the same power the current determines how fast the battery is drained (i saw leds in phones cnnected between resistor and ground each so i assume this is the way they are. if they are PWMed in newer phones then the current thing does not apply) are there any phones with backlight other than leds ? whats used in them ?
some are long lube ones like in stores<br />
The backlight is always white. Black and other colors are made with covering the lights
LEDs have never been widely used in cell phone screens. The screens, being LCDs, generally use fluorescent lamps as backlights. LCD screens with LED backlights are possible and have been done, but they are expensive and very far from being perfected. Also, higher voltage components require a <strong>higher</strong> current to operate.<br/>
this really isn't the place for this discussion. if you have a colored backlight, try changing the colors and see if it helps. good luck.
I've never heard that before, but that's an interesting idea, and with 1.5 weeks of battery life, it seems that all this helps. And yes, we'll enjoy life. :)
Has no one else come across the chargers that can recharge regular disposable alkalines? I have one, and it can be set to charge nicads, NiMhs or disposable alkalines. It works great. You can usually only get 10 or 15 charge cycles out of a disposable alkaline, but for low draw devices its great. If you get 6 months out of the batteries in a remote now you can get 60 months out of the same batteries. Seems like a damn fine idea to me.
regular ones cant be recharged on the one that say can like pure energy ones i have are alkaline but disposable will explode if&nbsp; u try cause they are not made to recharge.<br />
I want one too. What's the name of it?
i had one but it got lost in a move
&nbsp;i used seven 9vs and i could almost weld with them<br />
&nbsp;This is a really good instructable! Good job!
When our kids were young and had battery toys I sometimes bought a battery holder from Radio Shack. Used AA batteries were often no longer useful when each had gone down to 1 volt. But, I could gang three of them together in series with a battery holder and they would do the work of fresh 2 AA batteries, at least for a while. I might have to make a shunt from a dowel rod with a piece of copper wire to reach around both ends.
You know, that makes me think of a great idea. Why not use the low batteries that don't work for high current devices and use them on devices when a little current doesn't matter. That would probably work for small projects. In fact, the low voltage may actually be good for when LEDs are in use.
Back in the 1970s I acquired a calculator clock. It was very cutting edge at the time. It also used a couple of expensive watch batteries. I made a walnut holder for it so it can sit on my desk. Under the walnut holder I placed a battery holder for 4 AA batteries. When the AA's in my audio player were too depleted for the player I put three of them in the calculator clock battery holder with a shunt. Allegedly dead batteries will power the calculator clock for about one year.
Now that is a good idea. Since the clock uses so little power, it can use up all that little power in the battery. That way, you aren't wasting the power in the battery that you paid for.
I always charge NiMHs with the little current
I have to agree with ThinkDunson on the application of Alkaline. My points of reference are 1] a portable Cd player that fails to perform correctly on Nicads. 2] An early digital camera that used 4 AA's and would take only 10 pictures on Alkaline, but was ok on Nicads. 3] Model Aero flying, powering that servo he mentioned. Keeping 12 nicads fully charged before going flying was a complete chore and with a cheap charger that one is likely to buy, prone to overcharging them. That shortened their life, exacascerbating the problem. Plug your laptop in for a full charge. Leave it for a week unplugged and switched off. Will you be surprised when it reports your battery is less than fully charged? Practical experience with Nicads and NiHi cells shows they don't hold their charge over long time. They may when they are new, but this deteriates. Would I want to power my smoke alarm, my remote control with them? Not unless I wanted to keep on my toes with recharging them, and it would be a real chore to have to wait 18 hours for them to recharge before I could change channel on my tv. That focuses on the one singular point that ThinkDunson makes, its their convenience for low power applications or occasional use.
Maybe you can buy 4 AA's, 2 for powering your remote control and 2 to replace the other 2 when they are empty
<em>You spend $80 dollars a year on disposal batteries every year,</em><br/><br/>Redundant.<br/>
You could put contact grease (or whatever YOU call it) on the contacts of the battery. You could use rechargables. That would save the actual waste. Or, you could do what I do and just buy old, half broken solar hard lights and hard-mod the solarpanels in so that almost everything I own is 100% or 10% solar powered.
Agreed, rechargeables would be the ideal solution here. For some reason, greater america thinks that disposable batteries are actually a deal, when one rechargeable battery is worth over 1000 disposable batteries, at the minimum.<br/><br/>Rechargeable non-alkaline batteries (such as NiMH {nickel-metal-hydride}) are not only the obvious choice for economical and ecological reasons, but actually are better for your electronics. NiMH batteries hold voltage nearly constant as the battery discharges, then relatively suddenly, loses almost all power, where alkalines just go downhill from the start. As the voltage drops, your (e.g. digital camera)'s electronics have to work harder just to produce the same output, increasing wear and tear, until there is simply not enough power available to perform. Alkaline batteries run out like momentum on flat ground, the non-alkaline rechargeable runs out like a gas tank.<br/><br/>Alkaline rechargeables are a ridiculous attempt by the battery industry to salvage use of their alkaline production and get a hold of the rechargeable market. Don't buy them, because all alkaline batteries work on the chemical destruction of another element, usually copper and zinc.<br/><br/>Buy the REAL rechargeables for the highest Ah or mAh you can find (amp-hours= will last one hour with a load of one amp...2500mAh will last 2.5 hours on a one-amp load, or one hour on a 2.5 amp load....go look it up) and a charger. The money you spend to get started will pay for itself more than 250-fold if the batteries are properly maintained and used.<br/><br/>Would you buy, or even consider buying disposable car batteries? Cell-phone batteries? iPod batteries? No, that'd be ridiculous, because you'd be changing the battery at least twice a week...seems silly when you can just recharge them...so why are you buying disposable batteries for everything else? Convenience? Conveninece is not having to go to the store to buy new batteries in the first place, when you can just take the ones from the charger....<br/><br/>You spend $80 a year on disposable batteries every year. I spent $35 for all the equivalent number of rechargable batteries and a charger 5 years ago, and haven't bought nor thrown a battery away since. You do the math.<br/><br/>Consider the batteries you throw away every year, and then multiply that by 7.6 million. Now you see how much money that wastes, and how much landfill that is, I hope.<br/>
i assume that when you say one rechargeable is worth 1,000 alkalines, you mean because the rechargeable can be recharged about 1k times. (btw, they can be recharged at <em>most</em> 1k times, not at <em>least</em>. and the higher their capacity, the shorter their life.) but what you're not considering is that alkaline batteries last much longer. so one alkaline battery might be equal to two or more recharge cycles, instead of only one as you stated. meaning that one rechargeable battery is worth 500 or less alkalines, not 1,000 or more.<br/><br/>today's electronics are not as stupid as they used to be. the voltage curve of a battery doesn't matter any more. your digital camera will shut itself down when the voltage gets below a predetermined threshold. (btw, who still has a digital camera that takes AA batteries? get a new camera!!! you're missing out on a lot of fun, convenient and useful features.)<br/><br/>alkaline batteries are still around because people still need them. there are certain times when they are better. NiCad and NiMH batteries lose charge a whole lot faster than alkaline. so it would make much more sense to put an alkaline battery in your tv remote control. you can either replace an alkaline once a year or so... or you can recharge your NiCad's every week or so.<br/><br/>the bottom line is that alkalines are still the best choice for low drain devices like smoke alarms, or devices that aren't used very often like flashlights. (then again, i use non-rechargeable lithiums in my flashlight, and they only last a month or so. i meant for most people who only use a flashlight when the power goes out.)<br/><br/>having said all of that, i don't use alkalines. if you can afford those energizer lithiums, they last like ten times longer than alkaline. literally. for me, they are well worth the ten bucks for only four. in a remote control, they pretty much last forever. and any time i buy something that takes a rechargeable, like a drill, i always pay more for the one that has a lithium battery. well worth the extra price, if you can afford it.<br/>
"but what you're not considering is that alkaline batteries last much longer. so one alkaline battery might be equal to two or more recharge cycles, instead of only one as you stated. meaning that one rechargeable battery is worth 500 or less alkalines, not 1,000 or more." Not true at all. First, you may notice that the amp-hour rating is never stated on an alkaline, but in actual tests the overall power output is far less. The illusion is because alkalines drain on a more constant gradient, instead of rechargeables which deplete more like a fuel-cell. The average alkaline D-cell produces about 3.2AH, the average NiMH D-cell produces 4.5AH or more. "today's electronics are not as stupid as they used to be. the voltage curve of a battery doesn't matter any more. your digital camera will shut itself down when the voltage gets below a predetermined threshold." True to the extent that many will shut down at a preset voltage of usually 60% of nominal, but alkalines will go below this threshold much faster than any recharegeable. The Lithium or NiMH rechargeable will retain voltage as long as it can, until it's charge is spent, whereas alkalines will degrade on a relatively linear curve. "the bottom line is that alkalines are still the best choice for low drain devices like smoke alarms, or devices that aren't used very often like flashlights. (then again, i use non-rechargeable lithiums in my flashlight, and they only last a month or so. i meant for most people who only use a flashlight when the power goes out.)" Disposable batteries are not best for these applications either, despite that the internal resistance of such is greater than that of rechargeables. Disposables are best used for devices you expect to not recover again. There is simply no excuse for using a disposable over a rechargeable battery with exception to this one rule. The real bottom line is that you are recharging the batteries for your remote, instead of replacing them and dumping them into landfill. For the money you spend on disposables in 10 years, you can buy a century's-worth of batteries for you and all your friends, and still have enough to make a down-payment on a house. The extra price of a disposable lithium isn't worth the price at all when it cannot be used to it's peak capacity. FYI: "rechargeable alkalines" and such are a total scam. The manufacturers are desperately trying to protect their investments in disposable battery production. Regardless of usage, a rechargeable battery is almost always the best choice, unless you do not expect to recover the device again. Just as well, many digital cameras still take AA batteries, and this should be a motivation for buying them, so you are buying new rechargeable batteries, instead of the same batteries shrink-wrapped into a plastic holder and paying more than 300% of their actual value. This is yet another attempt to capitalize on american niavete by convincing you to buy "battery packs" and pay a 100-200% markup for a simple plastic spacer to hold the same batteries you could buy at the store. Who still has a digital camera that takes AA's? Those smart enough not to invest in this absurd idea of proprietary battery packs and chargers for them.
i don't care how you want to twist it... disposables last longer in low drain devices, even if the capacity is lower. and i don't know where you got your information from, but as far as AA's go, alkalines are usually a tad bit higher in capacity (about 3Ah) than NiMH (about 2.9Ah). you know what, i've never even seen a rechargeable D cell, the last time i used a D cell was years ago. do you have a camera that takes D cells?<br/><br/>oh, and let's not forget that every recharge cycle sees a diminished capacity! it may be small if you take great care, but i don't know <em>anyone</em> besides myself who does.<br/><br/>another reason i choose disposables is the higher voltage. a servo driven at 1.5 or 1.6volts gets so much more torque and rpm than it does when driven at 1.2volts. that's something you simply can't argue against. it's a fact, and it justifies a disposable all by itself for me. plus, some things aren't designed to be used with rechargeables because of their lower voltage. a device that uses four alkaline batteries is running on 6volts. try to put four rechargeables in there and it's only getting 4.6volts. some things actually tell you not to use rechargeables because of this.<br/><br/>&quot;<em>...will retain voltage as long as it can...</em>&quot; you make them sound almost intelligent, but it's utter nonsense. you could say that about any battery. when people start talking like this, i get suspicious. they're trying to make it sound better without actually giving you any information. my glass stays full as long as it can, too. now that's high technology. &quot;<em>...until it's charge is spent...</em>&quot; more nonsense! just when exactly is it's charge spent? when it gets below that threshold!!! my disposable retains it's voltage until it's charge is spent, too. brilliant! when a rechargeable gets below the threshold, it still has some charge... so you can't say that it keeps going until it's charge is spent unless you mean until it gets to that low threshold. in other words, you didn't really say anything. i call that type of argument propaganda.<br/><br/>when did we cover using a disposable lithium to it's peak capacity? that just came out of nowhere.<br/><br/>the only good argument you made, in my humble opinion, is that rechargeables are better for the environment. this is true when a rechargeable is warranted. but i'm not going to waste money and time for less convenience since the few batteries i use every year don't really make a big difference. yes, i'm a typical american pig. but isn't convenience the whole point of most of my battery powered devices? if you were that concerned with the environment, you would simply do without your precious batteries. shame on you!<br/><br/>i'm not arguing that you shouldn't use rechargeables, i use them... i'm just saying that they aren't the answer to every situation.<br/>
FYI, alkalines degrade in charge on a steady gradient from their peak of a full charge. Rechargeables degrade in voltage and amperage very slowly, until such time that the charge has been spent, where it suddenly drops. If you actually look at how alkalines perform, you would see this. This is not only better for electronics, as it is almost an automatic "low-voltage cutoff", but also more stable as a battery in general. I know of no digital camera that takes D-Cells, nor did I ever imply such. You created that idea on your own. Suddenly you are talking about servos, and unless you are employing AA-cell Ni-Cad batteries on a large portable robotic device, that argument has no merit. Sure, the open-circuit voltage may be higher, but the voltage-drop is less under lead-acid, which is what you should be using for higher-load devices. True, nominal single-cell NiMH voltage is 1.2V compared to an alkaline's 1.5V, but I have never heard of, nor seen any device that has warned against, nor is logically unable to use rechargeables for any reason. Your disposable will be down to 1.2V in short time anyway, so this argument also has no merit. At the same time, all devices such as cameras and remotes are required under electrical-engineering standards, to run at +/- 20% of nominal voltage, and not be adversely-affected in their operation in the least. Each recharge cycle for a properly-maintained "proper" rechargeable battery sees a diminish in output only after approximately 300 cycles, and of about 0.04% each cycle thereafter for Ni-Cad (now obsolete due to performance and mercury-content). Maybe you need to buy some quality NiMH batteries instead. What you fail to notice is that each composition has different characteristics. Alkalines drain like a slowly-leaking glass of water, NiMH maintains it's power until a third constituent in the battery removes it's ability to maintain it's output. With alkalines, it's recovery-rate is proportional to the load placed on it prior to the circuit being open, something like Ni-Cad or NiMH's recovery rate is low, but unlike alkalines, the charge is not weakened nearly as much. Maybe you better find out for yourself what an amp-hour is, because no AA alkaline in existence is capable of 3AH, and only the most expensive rechargeable can manage 2.9AH. Do you have a brand-name to verify these alleged values, so I can buy some and hook them up to my power-supply loader to verify your proven claim? I'd sure like to see a 3AH alkaline, since last I heard such a small amount of alkaline compound was not capable of producing that amount of current without out-gassing sulfates. As far as convenience goes, I find popping them in the charger overnight to be far more convenient than having to get replacements at the store, even if recharging is done every few months instead of replacement annually. Finally, remote-controls for devices like DVD-players and cable-boxes will run on as low as 1.8V on average and still perform until the LED simply cannot be luminous-enough to allow significant-range, or the controller cannot pulse at an intelligible range for the device to accept it's commands. You can say you are not arguing your point, but you are, and I have no problem with that. I just know that there is no logical or feasible excuse for disposables over rechargeables when the device is recoverable and not sealed. Low-drain devices are not an exception at all. I've made my point, you made yours, I think we have both stated our views. All you are really left with is the case of low-drain devices, but for me that still does not hold water, and your claim of convenience is easily-dismissable. I have done robotics for awhile, and never found a disposable to be worth the effort economically or logically. They are obsolete technology, but if you choose to dump these ecologically-harmful chemicals every time you need a new battery, instead of simply recharging one, I suppose I cannot convince you otherwise. I suppose that's your choice, just remember that your kids are drinking that water 20 years from now.
I apologize for being a bit late for the party but i just can't stay out of this. I once read about a rural fire brigade who had all their hand held two way radios converted so they could be run on disposable alkalines. The reason being that in the winter(wet season) there could be long periods between fires/emergencies, and when there was an emergency the last thing they wanted to worry about was making sure their radios were fully charged. If they put a new set of disposables in them after each use they could be sure that they'd work the next time.
Good point, I especialy like the part about the gas tank.
If those batteries are like gas tanks, wouldn't that mean the Alkaline ones are like compressed air tanks? The pressure would become weaker as it is used so the device would need to work harder or have the efficiency be reduced (like a paintball gun). Then again, what if it had a regulator? Then it would keep a constant pressure and stop working altogether when the pressure reached a level too low to work properly. That would be the case with the alkaline batteries in high power devices. They would stop working altogether when the voltage gets too low. With the other batteries, it would work longer because the voltage was constant, and when it stopped working, it would really be all out of power.
That's a good idea. I'll add that to the Going Green section.
I'm not sure how contact grease helps batteries last longer, but modding in solar panels is an interesting idea. Mount a giant solar panel on the back of your laptop screen and maybe you can save yourself a bit of power, :).
the PC Decrapifier (seriously, that is its name) is a great tool for getting rid of the junk that runs in the background. I don't have the link to it right now because I am using a friend's computer (I fried mine with a cup of tea), but you should be able to find the tool through a quick internet search. Last I checked, it was still free.
ah.. the dreadfull cup of tea, i nearly fried mine with a Glass of Iced tea, but luckily i hit the power switch and got a tower REALLY quick. =)<br/>
I need to freaking recycle my batterys I have over 10 kilo's of dead disposables!
It should be noted to be careful when tossing batteries in a bulk bin like this, for axial style (ie cylinder with two ends) this should be okay because the ends will most likely not be shorted together. However for 9V batteries or lantern batteries it may be a good idea to put some tape or something over the terminals so that they can't short out. Even if a battery is low there is a chance of fire if you short the terminals together. All in all a pretty good tutorial, I already do most of this stuff already but I hadn't thought of emptying the cd tray on my laptop if its not in use.
That is a good point for the 9V and lantern batteries. You should use some kind of cover for it or at least put in some bag.
It is a pretty good point. What I like about the lantern batteries is that they usually come with covers over the leads anyway, so you could just save those and tape them down when you recycle them.
Newer phones don't usually have this issue, but an interesting thing that a lot of people don't know about is that if their phone goes into analog signal reception, it drains the battery life tremendously. This is because the phone is constantly sending and receiving instead of sending in pulses of on and off. That said, if your phone has the option, it would be wise to shut off the analog reception capability. I did this for my LG phone when I was doing my pre-mobilization train-up, and I found that a lot of places where my phone was switching to analog still had a digital signal, so I was able to continue talking instead of losing the call and battery life in those areas.
another option (which many people don't even realise works) is to turn down the volume some. I have a cheap little mp3 player from Germany, and it is battery powered (not even a rechargeable device). I noticed that if I put louder headphones in and turned down the volume about 50% that the battery life increased about 33%. That is a fairly decent increase if you have higher quality batteries (the cheap batteries I use don't make things any easier).
Another 2 things you might want to add, remove any unused laptop attchments, i.e. joysticks,empty usb hubs, ipods that are fully charged... any thing you have plugged into your laptop uses some power.And also, don't overcharge batteries. e.g.When your laptop or phone or whatever is fully charged, unplug it. Overcharging batteries can actually reduce the life of them. Also, very good instructable, 5/5 and faved.
With the cell phone part, another useful measure with 3g phones is to turn switch it back to GSM only. Or if u really need video calling or whatever just put it on duel mode. Even that can improve battery life. I have a nokia 6500 slide and by default it was on UMTS only. The first thing i did after getting it out of the box and charging it was to put it on GSM only. The 3g is more power intensive. I usually get just over a day of power when using it for a music player etc with UMTS only, but on GSM only it more than doubled its battery life
Great tutorial. You're only thirteen? Keep up the good work. Great idea about using the residual power in batteries for low power consuming electronics. That was one I hadn't though of before. Thanks.
Thanks for the comment. I actually thought of that idea because, for my science fair, I couldn't find any batteries to use, and I dug up a few old ones in my room and I tried those in my camera. At first, they didn't work in my old digital camera (AA batteries) so I thought they were dead. I put them in this container, originally intended for the recycling bins. I accidentally used some of those batteries for my project and they worked (just to run some LEDs). After the fair, I realized they were the old used ones. That's why I added that little bit to this section, because it is a good way to make use of the little power.

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