Lion Battery Question?????

Mike Iver

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Sep 30, 2006
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I recently purchased a UltraFire LiIon intelligent charger ( model WF-139 ). I also purchase some DX 14500 batteries. I have been intrested in the 18650 batteries and lights. I also am intrested in other sizes as well. My question is this - how do the all the lion batteries perform? It looks to me like the 18650 battery is a winner for perfomance/runtime, but how do some of the other battrey/light options perform? I guess that I want is really bright lights with a really long run time. Who dosen't? I think that I need a light to be able to produce an hour of runtime. How do the rechargeable CR2s and CR123s and some of the other combonations perform in some of the better lights? How big of a deal are the protected cells? I understand that they are much safer as far as charging. Aside from that if you didn't run them down all the way - is their a reason to spend the extra dough for protected cells?
 

LuxLuthor

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Mike, you asked some good questions, but in general the larger size Li-Ion cells give you more mAh capacity at the same 3.7V. It's not a matter of better quality within a particular brand, just the difference in capacity. As far as which capacity size is best...that depends on the battery holder/light size you are trying to match up with. Various lights will only allow a certain diameter and/or length...so you have to start with the size of the light tube first. It's pretty hard to give you any specific answer other than that about your general questions about sizes.

The issue of protected vs. unprotected is because there is a computer PCB circuit board that is added to prevent the cell from being overcharged, and to shut off before the light over-discharges it. Overcharging a lithium battery will result in an explosion and fire, which is why there are so many topics about that in this section.

Over discharging a Li-Ion cell will ruin it. The PCB will help prevent these scenarios, but nothing is infallible. Some have reported storing their protected Li-Ion's in the freezer which apparently damaged some percentage of their PCB protection. If you over charge a protected battery with much higher current, you can short out the PCB circuitry. If you drop a protected cell and it breaks the PCB board....no protection.

Even still, given the dangers and down sides to unprotected cells....it is almost always better to use protected. Obviously the unprotected are cheaper. They also allow more current to be output for higher demanding bulbs...so they have their place if you understand how to care for them.
 

mdocod

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if you are interested in incandecent lights powered by Li-Ion cells..... have a read through the guide I wrote on this topic... (link in my sig-line)... The guide isn't totally done yet, but is a good start.
 

LuxLuthor

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mdocod said:
if you are interested in incandecent lights powered by Li-Ion cells..... have a read through the guide I wrote on this topic... (link in my sig-line)... The guide isn't totally done yet, but is a good start.

Whoah! That is some PRIMO information there mdocod!!! I might make a friendly suggestion that you put it in the form of an HTML page just so you can separate it into good sections...and maybe have an index at top. It will take a while to read the whole thing, and it would be handy to be able to zero right into the specific info desired. In any case, a very hearty thanks for putting that much together....back to reading it now.
 

yellow

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You already know the right source: www.dealextreme.com
there are several 18650 hotwire lights there (usually if they look crappy and are priced cheap, they are it, but there are also some with decent quality. And for the price there ...)
Most of them will run about an hour on the 18650.

I prefer protected, as there is the risk of overdischarching the cell, while still the beam looks bright (never underdischarge under 2.5 Volts and thats a real low value already!)

Then You come to modding:
my 18650 / Cree / Flupic mod runs for about 2.5 hours @ 800-900 mAh to the led, with the 2200 mAh 18650s and blows away any other light I have (by now) ;)
Note there are, at the moment, no real "good" working circuits for white leds and single Li-Ions, as they would have to switch between buck/boost. The Flupic, as I unterstand it, makes some kind of PWM direct drive till short ofer 3 V of the cell, then output and draw from cell dimishe very much. This setup will not overdischarge a Li-Ion. I had it running for some hours till then, and only succeeded in a cell voltage of 2.8 Volts.
 

Mike Iver

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Sep 30, 2006
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How about the rechargeable cr123s. How do they perform in say a Fenix light? All the really nice lights seem to run on these cells.
 
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