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hooking up a 9-volt battery to a lazer pointer Answered

have you ever had a lazer pointer that was really fun, but then ran out of batteries? those little replacement batteries are hard to find. while I was supprised there weren't any instructables on this, I'll be posting one soon. I know how to use a 9-volt battery to power the lazer pointer again. this fuel cell is easy to find, and easy to work with. comments? are you interested?

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westfw (author)2008-01-26

The batteries aren't really that hard to find, though they tend to be extremely overpriced at americal retailers. Try something like Deal Extreme LR44 BatteriesLR41 batteries

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Patrik (author)2008-01-25

It turns out that 9V batteries aren't actually all that efficient, in turns of energy storage. See the discussion on the MintyBoost instructable:

9V battery: 9V x 500mAh = 4.5Wh power
AA battery: 1.5V x 3000mAh = 4.5Wh power!

Since it sounds like you need 4.5V, you could put 3 AA batteries in series - you'll get exactly the right voltage, and they'll last at least 3 times longer than the 9V battery!

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super_genius (author)2008-01-25

ya the most you can run one of those el cheapo 1$ lasers would be maybe MAYBE 5 volts. 9 volts it wouldn't last 10 seconds trust me i deal with lasers ALOT when im not in school and you have to get the voltages perfect. now if you could find a 4.5 volt battery or just use 3 AAA's with an AMPERAGE of like.. 125 amps, then you would be cooking. Ha, it's a pun.

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bigfootduck (author)2008-01-25

I need this Instructable so I can convince my parents to buy me a lazer pointer. lol

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VIRON (author)2007-05-12

take apart the 9 volt battery and there are smaller batteries in it, hopefully the round kind, especially if you have a pen laser that actually takes That Size (AAAA) of battery! Test the polarity because some of the AAAA's in 9 volts actually have the bump on the wrong end. Some 9volts have weird flat cells in them.

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Brennn10 (author)2007-05-11

Well wouldn't it depend on how much voltage the laser can handle?

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mexx.admin (author)2007-05-11

actually. my awesome "invention" broke. either it shorted out, or it had something to do with my dad running it over with his car a few times. lol

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Punkguyta (author)2007-04-17

9 volts is too much voltage to run a cheapy laser pointer on, at most 4.5 volts will be all you need and is very bright.

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HamO (author)2007-04-17

Sure, let us see it. That's why we are here waiting for each new Instructable.

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HamO (author)HamO2007-04-17

Well, most new instructables.

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