quick question ,if you add batteries does it add runtime

qip

Flashlight Enthusiast
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Jan 10, 2007
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got a mag2d with a led upgrade...if i switch from 2 d cell coppertops and put in 3 C cell coppertops ,will it add more runtime or just light output
 
You did not say what type of LED mod you are using. Some, like the ones made by Mag are cell number specific. Adding an extra cell will cause your runtime to be zero.

Some, that can operate over a wider voltage range, can benefit in additional runtime with an added cell.

Mark
 
i know it works with multiple cells , but how do 3c vs 2d go in output and runtime
 
Hello Qip,

When you add cells in series, you add the voltage. When you add cells in parallel, you add the capacity. Capacity = runtime.

Tom
 
ahhh as i re-read flashlight reviews i see its not reccomended for more than 2 cells
 
It's a quick question, but there is not a quick answer unless you do an actual test under the conditions that you will use the light.

The capacity of Duracell Coppertops depends on the discharge rate and other factors. You'd also have to know if your light engine is as efficient at 3 volts (2 D cells) as it is at 4.5 volts (3 C cells) and whether it puts out more light at the higher voltage and what the cut-off voltage is.

In general, however, there is 35 percent more energy in 2 D cells than there is in 3 C cells.
 
well now with my new info with the series and parralell, i think i would still keep the same voltage but add more batteries with the 2d to 8aa carrier and same goes for my 3dmag if i can use a 3d to 12aa carrier from sandwich shoppe, i just wonder if they can make a 3v version for a 2d and 4.5v version for 3d and have them wired in parralell so it in theory has same ouput and double the runtime ....does that sound right?
 
actually i think i got it wrong as the carrier would give me 10800mah if the aa alkalines are 2700mah each ....2d and 3d setup is 20000mah so im losing runtime






my brain hurts:mecry:
 
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8 AA Coppertop cells will have about 50 percent more energy than 2 D cells, but you'll have to bore your 2D light to make the loaded 8 AA carrier fit.

It's easier to compare the runtime potential of various cell combinations if you convert amp-hour energy to watt-hours, because watt-hours allow you to compare energy capacity in cell combinations of different voltages. Multiply amp hours by voltage to get watt-hours.
 
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