Using CR123's of *slightly* different voltages?

[bstrickler]

I have 2 CR123 cells, both with the same expiration date, with sporadic use on them. 1 is 3.02 volts, the other is 3.06 volts. I am thinking of using them in my 6P with a P60L, to use them up, but before I do, I just want to check if I should save em for later, when I get a light that accepts single CR123's (or a single 123 tube for), or if its safe to use them together.

I know you're not supposed to mix cells of different voltages, but I don't know if the 0.04 volt difference matters a whole lot or not, so I'm asking the more experienced people for advice. I don't mind if I have to put those in a "waiting" pile, because I'd rather do that, than risk getting hurt, or hurting someone else, because the cells exploded.

~Brian

 

[VidPro]

not supposed to mix cells . <-period

voltage of a wonderfull lithium cell doesnt tell all, if you want to test them for teaming them up with eachother, do so with at least a "loaded" voltage test. in an attempt to determine its actual state of power capability.
so tie a resister load to the meter, then test it. or connect to a bulb and test. or use one of them testers that applies a bit of resistance in or during the test.

to get a good "reverse charge" you need one to die before the other one (capacity), AND for the light item to keep drawing power after that cell is dead.

to test, is more simple than it sounds, if you got a picture .
http://www.candlepowerforums.com/vb/showthread.php?t=236906
about 1/2 way through this guide, when it gets to "Battery" HKJ shows the easy way to stuff a resister onto a meter with clip leads, then test the battery. that'll fix it

 

[mdocod]

Variations in open circuit voltage readings in primary CR123s are normal even amongst cells that are in the same state of charge, it's also possible for 2 cells in a very different state of charge to read very similar voltage.

The question you should be asking is not whether you can combine CR123s that are measuring slightly different voltage, but instead, can you combine cells that are in a different state of charge and still be alright?

Mixing CR123s in different states of charge is actually a proven way to stimulate a reverse-charge condition leading to battery venting with flames, poisonous gases, exploding flashlights, etc etc.

So, let me ask: How confident are you that these cells are in the same state of charge? Irregardless of voltage readings.

Eric

 

[bstrickler]

Variations in open circuit voltage readings in primary CR123s are normal even amongst cells that are in the same state of charge, it's also possible for 2 cells in a very different state of charge to read very similar voltage.

The question you should be asking is not whether you can combine CR123s that are measuring slightly different voltage, but instead, can you combine cells that are in a different state of charge and still be alright?

Mixing CR123s in different states of charge is actually a proven way to stimulate a reverse-charge condition leading to battery venting with flames, poisonous gases, exploding flashlights, etc etc.

So, let me ask: How confident are you that these cells are in the same state of charge? Irregardless of voltage readings.

Eric

Good point. Those cells are gonna be put aside, until I get a single-cell light, or a driver that handles CR123's.

~Brian

 

[Max_Power]

This issue is the reason why you should always use protected cells for any light that uses 2 or more batteries in series. A protected cell will not allow reverse charging to occur.

 

[mdocod]

Hello Max Power,

This thread is concerning primary CR123 (Lithium Manganese Dioxide) cells. You are confusing this with rechargeable RCR123 (Lithium Cobalt Oxide) cells.

Primary cells often come with a PTC device as a form of protection that kicks in under severe heat or high current conditions, but there is no electronic protection circuit to be found on CR123 primary cells like the circuits you might find on the rechargeable options out there.

Eric