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Old 07-05-10 | 09:53 AM
  #31  
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colleen c
I am a caffine girl
 
Joined: Nov 2009
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From: Bay Area

Bikes: 2012 Stumpjumper FSR Comp...2010 Scott CR1 CF...2007 Novara FS Float2.0...2009 Specialized Hardrock Disc...2009 Schwinn Le Tour GSr

Originally Posted by PaulRivers
P.S. One other question - would the P7 take AA nimh batteries or the CR...something that's lith-ion? Be aware that regular ni-mh batteries have a fairly steep rate of self-discharge if you don't use them a lot - in other words, if the batteries sits around for a while it loses stored energy just sitting there. You could read about it here or here if you want -
http://www.batteryuniversity.com/parttwo-32.htm
http://www.candlepowerforums.com/vb/...d.php?t=115650

It doesn't matter so much if you use the batteries regularly, but matters more if they'll sit for months at a time. There is an easy solution - buy the "low self-discharge" kind. Sanyo Eneloops are well reviewed, but I personally usually the Rayovac "Hybrid" batteries because they're $10 for a 4 pack at Target (probably Walmart to). Just wanted to mention it.
Problem with the P7 flashlight is that the LED requires 3.7 volt. That pretty much means having to use those 18650 battery. A single 18650 battery is larger in width and length as compare to a AA battery and output 3.7v instead of 1.5 for Alkaline AA or 1.2v nimh. So physically the body of the cell compartment cannot fit any standard AA. You can take a P7 and take it apart and trying to modified it for external battery. That means having to take something like 3x1.2v nimh to get close to the 3.7v, but that mean having to DIY the flashlight and a battery pack. Not worth the trouble when you can take a single 18650 cell and replace it with a freshly charge cell. Price wise, the cost of two 18650 cell and a charger is pretty cheap at $8 for 2 18650 and $8 for the charger. Those 18650 are smaller than 3x1.2v nimh and they are made for the heavy current draw from the P7 led. The other option is to use 14650 battery which are smaller with the correct voltage but runtime will be very short.

I notice that Amazon sell some flashlight as P7 that runs on AA. Check the lumen claim rating. They are listed in the 200 lumen range. The led on these are not the same as the P7 from DX. The price you pay for those are fairly high, you are better off getting a AA flashligt from Shiningbeam.

Last edited by colleen c; 07-05-10 at 10:10 AM. Reason: fixed link
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