9V battery operated flashlight.

nightstalker101

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I am begining to consider making a flashlight that runs off of 9V alkline batteries. I have about 200 9V batteries just lying around. I am considering useing a OSram 64655 lamp(10,000lm; 250W; 24V). I am asuming that the voltage sag of 3 groups of 9V's would sag enough to safly power the bulb. How many batteries would I need to put in groups to safley power the bulb. Thanks.

nightstalker101
 

Cydonia

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Wish I had 200 9v batteries just lying around. I'd use em in my Headroom Micro Amp and Micro DAC! (audio gear - two 9v per unit and run for 8 hours...)
 

Flash_Gordon

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You are talking about drawing about 10½ amps. 9V batteries are not up to this task.

For discussion, let's say you will draw 500mA from each group of 3 batteries. This is the high end of what these batteries will deliver and the voltage sag would be large. At 500 mA you would need about 21 stacks of 3 batteries.

By the time you factor in the internal resistance of all those batteries and the issues of all that wiring, you would light this lamp for a short time at certainly less than full output.

Double the number to 126 batteries and it should light and run for about 30-40 minutes if you can keep it all working.

Hardly seems worthwhile, IMO.

Mark
 

nightstalker101

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I'll change the question, What is the highest amount of A/mA that I can drow from a 595mA battery? Thanks again.
 

wmirag

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I would caution against putting batteries in parallel to get more current. Slight differences in voltage would make the higher ones charge the lower ones. Things could get hot, literally. And they might well self discharge into each other even when the device you are powering is off.
 

spanish

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Goes to Ebay, sell the batteries, take the money and buy something you like.
 

wmirag

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The brightest light I know of that uses a single 9V battery is the PalLight. Nice light for it's purpose but hardly bright.

BTW, a very nice use for 9V batteries is to serve as replacement "B" batteries for old tube radios. I restored an old Zenith TransOceanic two years ago. Of course 90V batteries are no longer available. But a series array of (10) 9V batteries did the trick. This only works becasue the B current is very, very small.

Note you can create dangerous and even lethal voltages by putting batteries in series. I think it only takes a small current through your heart to kill you. A stack of 9V batteries can certainly do it. Be careful!

W.
 
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roadie

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9V alkaline battery has a +/- 650 mAh

u can't "mod" them into the high amp bulb as alkaline cannot take more than 0.2C, right?

i use my extras 9 v on LEDs mod, use as night lights .....
( i am fear of the dark ...)

Else, like someone said, sell it off (to a local shop) or on the net, and buy yrself an ice cream ......etc
 

TigerhawkT3

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9Vs... No.

A 9V battery is six AAAA (that's right, quadruple-A) cells (either rectangular or cylindrical) in series. They can't handle much current at all. Here's Energizer's datasheet on their 9V batts (pdf) - notice how they only have data for current draws up to half an amp, and capacity is drastically reduced at that level. 9V batts just aren't suited to high-draw incans. Try powering LEDs with them instead.
 
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