My 18650 Setup and Multimeter

[amsgator]

Hello all,

I am about to purchase some 18650 batteries for my Fenix tk11 flashlight because it eats 123s way to fast. Here is what I've picked out over on DX.

It is my understanding that it is important to check the voltage of these every so often. Is this correct? If so, I need to purchase a multimeter as I do not currently have one. I have included one in the links below.

Trustfire 18650 blacks - DX 20392
Charger - DX 3499
Digital multimeter - Actron CP7672
Storage case for work bag - DX 18074

Yes yes, I know AW is CPF preference, but quite frankly I can't fork over their cost. I've researched and found the black Trustfire's are one of the best budget batteries, so I opted for those. All things aside, does this seem to be fine for the tk11 flashlight?

Also, when using the multimeter, what exactly should I be looking for? (I'm not very electrically inclined) Should I measure on charger, off charger, etc, and what to look for.

 

[amsgator]

Well I went ahead and ordered 4 batteries, 2 cases, 2 chargers, and the multimeter. Hopefully DX doesn't take to long to get it here.

 

[PapaLumen]

I have those trustfires, all good so far.
You want to measure the voltage (V-DC on your multimeter). One multimeter electrode on each end of battery. Nominal voltage is 3,7v. Fully charged 4.2v. fully discharged 2.7v ish.
So check them when finished charging to check they are at 4.2v. Try not to let them drop too low when in use. (i recharge when they reach about 3.5v on my bike light)

 

[amsgator]

so it's just probe to battery, no need for a resister etc? I was reading one of the how to use a multimeter posts and it got into resisters and stuff that completely confused me.

Is it ok to test the voltage while it's still on the charger or do I need to pull them off to test?

 

[ToNIX]

I was about to suggest charger 6105, but you already ordered.

On a separate command, I also purchased the plastic cases (3 weeks ago), still hasen't shipped... I hope that waiting for the cases won't mean you'll have to wait to get the batteries and chargers.

 

[amsgator]

I was about to suggest charger 6105, but you already ordered.

On a separate command, I also purchased the plastic cases (3 weeks ago), still hasen't shipped... I hope that waiting for the cases won't mean you'll have to wait to get the batteries and chargers.

I considered that one, but after reading the reviews I opted for the other. Both seem to have been pretty decent and I could get two of the cheaper ones for about the same price as the one. Hopefully it doesn't take too long, I really don't want to have to get anymore 123 primaries.

 

[gcbryan]

I considered that one, but after reading the reviews I opted for the other. Both seem to have been pretty decent and I could get two of the cheaper ones for about the same price as the one. Hopefully it doesn't take too long, I really don't want to have to get anymore 123 primaries.

It will take about a month if nothing is backordered. If you have to get CR123's shop around ...the price varies wildly.

 

[PapaLumen]

Check voltage when they are off the charger. The resistor thing is for when measuring current to the led not voltage.

 

[Bullet120]

As far as shipping times go, I ordered 8 ultrafire 18650's and a wf-139 on the 13th and received them on the 24th. I was pretty satisfied with everything.

 

[amsgator]

yea, it says mine is being packaged. so hopefully it ships soon