Are Protected Cells Potted?

Cardnyl223

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I know potting on light circuitry is pretty common. I was wondering whether or not the protection circuitry on 18650 or 14500 cells are potted? Are there any companies known for potting their cells like this? Is this not something I should worry about regardless of manufacturer because its industry standard for protected cells?

I'm trying to buy some batteries to use on weapon mounted lights and want to make sure that they will hold up to commons events (recoil impulse) and uncommon events (weapon being dropped, banged into a barricade or wall, etc.) without becoming damaged.
 

scalpel_ninja

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I know potting on light circuitry is pretty common. I was wondering whether or not the protection circuitry on 18650 or 14500 cells are potted? Are there any companies known for potting their cells like this? Is this not something I should worry about regardless of manufacturer because its industry standard for protected cells?

I'm trying to buy some batteries to use on weapon mounted lights and want to make sure that they will hold up to commons events (recoil impulse) and uncommon events (weapon being dropped, banged into a barricade or wall, etc.) without becoming damaged.
I have neither seen nor disassembled any protected cells that had potting. The protection circuit is usually spot welded, glued, or just sealed under the plastic shrink wrap.

I don't know the specifics of what a WML requires, but don't mission-critical applications need primary CR123s?

The addition of a protection circuit on a Li-ion cell adds another layer of complexity and point of failure. Unprotected cells might be a simpler solution, will just need a closer eye on maintenance and charging to prevent over-discharging in a light without LVP.
 

vicv

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Personally I don't think protected cells are necessary anymore. Lights have gotten a lot better since they first came out. So I would either go unprotected, or better yet use primaries.
 
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Cardnyl223

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For additional context, the light in question is new SureFire M640DF Turbo. I don't think it has any form of LVP built into it but its possible I missed it when looking through the manual or specs sheet for it. SureFire includes and separately sells SureFire 18650's specifically for use with this light. I'm highly doubtful they make the batteries themselves and are probably buying these from one of the usual manufacturers.

I can use primaries in the light but the output on it is higher with the 18650.
 

vicv

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For additional context, the light in question is new SureFire M640DF Turbo. I don't think it has any form of LVP built into it but its possible I missed it when looking through the manual or specs sheet for it. SureFire includes and separately sells SureFire 18650's specifically for use with this light. I'm highly doubtful they make the batteries themselves and are probably buying these from one of the usual manufacturers.

I can use primaries in the light but the output on it is higher with the 18650.
Nice light. By eye you'll never notice the loss of 300 lumens. But if you want to go the rechargeable route, no surefire does not manufacture the cell. But I'm sure it's a very good quality. As for an unprotected cell, when the light gets dim, charge it.
I'll admit I'm not well versed in weapon mounted lights and their use. But aren't they kind of supposed to be there on your forearm, possibly for years, without being turned on? I mean it's for an emergency situation. For that use, primary cr123s are the right choice. An 18650 will be wasted in that situation
 

Cardnyl223

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Nice light. By eye you'll never notice the loss of 300 lumens. But if you want to go the rechargeable route, no surefire does not manufacture the cell. But I'm sure it's a very good quality. As for an unprotected cell, when the light gets dim, charge it.
I'll admit I'm not well versed in weapon mounted lights and their use. But aren't they kind of supposed to be there on your forearm, possibly for years, without being turned on? I mean it's for an emergency situation. For that use, primary cr123s are the right choice. An 18650 will be wasted in that situation
Folks buying weapon lights that aren't training with them and leaving them in a hiding spot, gun safe, etc. for an emergency would benefit from primaries.

If your signing up for night shoot classes, doing force on force (be it airsoft, simmunitions, etc.), clearing structures with unloaded weapons, etc. I think the costs on rechargables are justified over primaries.

I fall into the latter of these 2 camps but I'm still still a big proponent of keeping a box of 123's on hand in case of natural disaster.

It is good info to know that as long as I'm careful its possible to use an unprotected to bypass any concerns with potting. I appreciate everyone taking time out to respond - thanks all.
 
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