noob question - 2*18650 light

mclight

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so I got a new Trustfire LED light, takes two 18650 cells. This is my first LiIon 18650 light. The light came with a Trustfire TR-001 charger - I'm charging the cells.

there are no instructions that came with the light.

here's the dumb question: I've read enough to be paranoid about LiIon batteries - I don't want to have little bombs going off. In a two battery flashlight, do you put the 18650's in like normal alkaline batteries - open the tail end and put the batteries in + end first? First battery in + end first, then second battery in right behind it + end first? The Trustfire light I got has springs at both ends of the battery tube. I'm used to seeing the end that takes the + side of the battery being flat. So just want to make sure I get these in correctly. Thanks :)
 

bstrickler

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Yep, you have it all correct. Positive always goes in first.

I have never seen a flashlight that has you put it in negative first. That will cause way too much confusion.

~Brian
 

bstrickler

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If it suddenly gets hot, chuck it into the neares popul.... Errr. Unpopulated area. If theres a good sized puddle/pond nearby, that will be safer than the light exploding near you.

Remember!!!! If the light suddenly shuts off, DO NOT LOOK AT THE LED!!!!! I've seen horror stories here on CPF about people who have done that, and nearly lost their eyes, because the front of the light blew out, sending lens shrapnel into their face.

If the light shuts off suddenly, make sure its not hot. If it's still cool, unscrew the tailcap, and check the cells. If they're warm, drop them away from you, and get far from them, for at least 20 minutes. If you go back near them, make sure you are wearing good face protection.

~Brian
 

PerttiK

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If your cells are unprotected, you have to be very careful to not run them totally dry.
You might run in to trouble when charging totally depleted cells.
 

HKJ

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Yep, you have it all correct. Positive always goes in first.

I have never seen a flashlight that has you put it in negative first. That will cause way too much confusion.

Not always, I have a few flashlights where - goes to the head of the light.
 

mclight

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thanks everyone. I have protected TrustFire cells. They charged up pretty quickly on the TR-001 charger. And I took the light out last night, no heating up or anything - worked great.
 

Echo63

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Yep, you have it all correct. Positive always goes in first.

I have never seen a flashlight that has you put it in negative first. That will cause way too much confusion.

~Brian

Some Inova models go negative first, as do the surefire E series lights (although the surefire is fed from the front, so Negative goes in first, but towards the tail)
 

bstrickler

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Some Inova models go negative first, as do the surefire E series lights (although the surefire is fed from the front, so Negative goes in first, but towards the tail)


I guess I didn't think that one through. I should've clarified myself. Should've said "You usually have to feed the cells so the positive end is facing towards the head."

~Brian
 
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