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QUESTION: Is there any 3.7v rechargeable Li battery that is the same size of AAA

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I have a green laser pointer pen but every time I use it, it always run out of power and i decided to buy a new rechargeable battery, which will improve the laser efficiency. if i have a 3.7 v battery the size of AAA, and another completely discharged battery, it might improve the laser power output (not the actual power output but i think the light intensity)
 





daguin

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Search for a 10440 battery

However, instead of using a discharged battery, use a "spacer"
This can be a simple as cutting a bolt (the right diameter) to the length of an AAA and then wrapping it with electrical tape

Peace,
dave
 
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lastly, can i use higer voltage for a green laser pointer cause i used to supply it 2x1.5v battery, can i increase it for about .7v? is it safe for the diode?

thanks
 
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daguin

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lastly, can i use higer voltage for a green laser pointer cause i used to supply it 2x1.5v battery, can i increase it for about .7v? is it safe for the diode?

thanks

You have to decide to take a chance here or not

Some drivers/diodes will take it

Some will not

There is no way to tell which will and which won't :(

Peace,
dave
 
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^ Like dave said, it is up to you to decide whether your laser is worth the risk or not. I had a cheapo green pen that would refuse to lase on anything other than brand new batteries, and then the runtime was about a minute before I had to change batteries.
I now use a protected 10440 and a spacer. I constructed my spacer from a segment of PC power cable, with self-tapping wood screws screwed into each end to make contact with the wire inside. It's hard to describe, but a very simple concept.

If you want to be overly cautious, you can add a diode inline with your battery (i.e. you can put it in the spacer, but the spacer will then be polarity sensitive) to drop a few extra tenths of a volt. Might bring that 4.2V down to 3.6V or so, still extra voltage, but not too much over the 3V specification.
 
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never use a 3.7 and a dead primary -- fashion a spacer that allows the voltage pass thru.. imo you prolly will have n/p. but a risk is there. I have made portable mini green labbies using modules from 532 poiners and a 18650-- without any issues- and a good long use before recharging... also some rechargeable aa and aaa only make 1.25 vdc which won't work very well or very long, but I have had fairly good results using three of these--3.75v..total. Same deal with flashlight hosts that take 3 AAAs in a holder..like a drocy jr. for 405 use three 3.7 to get 9+vdc..ANd if you rewire to change from series vs parallel you get 3.7 vdc with very long time between charging. hope this helps---hak
 
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so to sum up, im gonna use a diode in my spacer to become more safe for the laser diode, and wait, can i use a resistor plus the diode to MAKE sure that is is way better than a single diode only?


thanks to all!

EDIT: what is the maximum voltage that a common laser pointer (especially the pen type) should get? im getting nervous to burn the diode,, is 3.6v still safe?
 
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generally speaking, the maximum voltage for laser pointer pens is the voltage of two alkalines, can be up to 3.2 or 3.3V.

The idea behind the diode is to lessen the risk. There is still risk, and again you must decide if the risk is worth it to you. The benefit, though, is being able to supply MORE voltage, because more voltage basically means that the battery can push the current through the device more strongly, which is why you would want to do this modification in the first place.

I have a cheapo amazon green laser pointer that I use this mod for. The pointer cost me $12, not to mention it was a gift card anyways, so I felt like if I fried it, I don't really lose that much.

I also have a more expensive laser pointer that I will NOT use a 10440 with, because it is the nicest completed product that I own. I do, however, use AAA NiMH Duraloops with it.
 
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thanks to all! im gonna connect a resistor to my spacer or just a diode to bring the voltage down. many thanks
 




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