Reliability & Safety - 1x18650 versus 2xCR123a -are Surefire/Elzetta right?

[Modernflame]

How do you know if the protection circuit in your 18650 has failed? I use only unprotected cells in my 1 x 18650 lights, but I use protected cells for 2 x 18650 configurations. Recently, I bought a new pair of protected 18650's. The first thing I did after unboxing them was drop them onto my tile kitchen floor in their side-by-side plastic case. Butterfingers!

The impact was sufficient to crack the case, but I don't know if my PCB's were damaged. I charged them to 4.1v with hawkish oversight and eventually got the courage to discharge them to about 3.7.

Was I foolish? Should I discard them? What's the best way forward?

 

[FlashKat]

Your batteries will be fine especially since they were in a plastic case.
The batteries usually won't charge if they fail, and being in a plastic case there is a very low possibility of hitting the protection circuit directly.

How do you know if the protection circuit in your 18650 has failed? I use only unprotected cells in my 1 x 18650 lights, but I use protected cells for 2 x 18650 configurations. Recently, I bought a new pair of protected 18650's. The first thing I did after unboxing them was drop them onto my tile kitchen floor in their side-by-side plastic case. Butterfingers!

The impact was sufficient to crack the case, but I don't know if my PCB's were damaged. I charged them to 4.1v with hawkish oversight and eventually got the courage to discharge them to about 3.7.

Was I foolish? Should I discard them? What's the best way forward?

 

[Modernflame]

Your batteries will be fine especially since they were in a plastic case.
The batteries usually won't charge if they fail, and being in a plastic case there is a very low possibility of hitting the protection circuit directly.

That's a relief. Thank you.

 

[slumber]

This is probably a bigger factor in the reliability argument than failures of the technology. Rechargeable batteries, even when working correctly, have a maintenance cost that's usually negligible to an individual user or hobbyist but very real to a large organization.

Very well said. To some guys, recharging batteries itself is a hobby. I'm not that interested in charging, discharging and measuring batteries. Don't get me wrong, I do use and carry 18650's in some lights, but it's not mandatory and in some cases, less desirable.

 

[marinemaster]

Reliability & Safety - 1x18650 versus 2xCR123a -are Surefire/Elzetta right?

Surefire got it right 20 to 30 years ago. There are probably more people that used the 6P with the 2x123 than any other light in the field while being very reliable. Same goes for Streamlight.

 

[Chad Varnadore]

Re: Reliability & Safety - 1x18650 versus 2xCR123a -are Surefire/Elzetta right?

Surefire got it right 20 to 30 years ago. There are probably more people that used the 6P with the 2x123 than any other light in the field while being very reliable. Same goes for Streamlight.

I've owned several Surefire's requiring 123s, both incandescent and LED. 20 years ago we were firmly in the single-mode (on or off - no low power option), incandescent generation, which meant 20-30 minutes runtime on $6-$10 in batteries. Nobody carried Surefire that I knew. I've always loved Surefire, but battery expense always prompted me to regulate their lights to less used weapon mounts and backups. The main light I used was a rechargeable Maglite. Every officer I knew back then carried Mag or Streamlight with long rechargeable sticks you charged inside the light. You even kept it on a mount in your car so that it was always topped off.

Surefire definitely got it wrong with 123s from my perspective, at least in requiring such for all their lights with no rechargeable options available. Otherwise they might have surpassed Maglites and Streamlights market share in the late 90's, early 00's at the latest. Even today 123s are too pricey to be any kind of enticing for someone pulling 3rd shift.

Even my last Surefire - which was an early gen LED I bought for a cross country motorcycle trip where a large rechargeable Mag was less feasible than a light small enough for pocket carry and a case of batteries - was pretty much shelved most of the time after my return, until I finally found a set of rechargeable 123s that would work in it some years later; then it got used regularly for a while. But with the new generation of 18650 lights, I've got more flashlights than I need and I use at least four of them almost every day. And I'm still looking for more. I've still got a couple unused 123s from the last case I bought from Surefire almost a decade ago. I only keep them around should I need the only Surefire light I haven't sold off, which is mounted to a Remington pump that hasn't even been fired in the daytime in about four years, and is mostly just on home security duty. I can't even remember the last time I used it at night.

 

[carnage]

Re: Reliability & Safety - 1x18650 versus 2xCR123a -are Surefire/Elzetta right?

For a newbie to Lithium Ion is it a safe idea to get a non protected cell and get a flashlight with a low cell warning?

 

[terjee]

Re: Reliability & Safety - 1x18650 versus 2xCR123a -are Surefire/Elzetta right?

For a newbie to Lithium Ion is it a safe idea to get a non protected cell and get a flashlight with a low cell warning?

Yes, if:
- it's a quality light
- it's a single-battery light
- you take some precautions when battery is outside the light

Then it should be just fine.

In fact, it's far more likely anything bad would happen outside the light, than inside it. My advice is to never have the cells "naked", but move directly from light to case/sleeve. Google "18650 silicone sleeve" btw.

Oh, and also, "safe" is relative. It's safe in the same way as fueling up your car. Millions do it every day, but it's safe because they're careful.

 

[Modernflame]

Re: Reliability & Safety - 1x18650 versus 2xCR123a -are Surefire/Elzetta right?

I've owned several Surefire's requiring 123s, both incandescent and LED. 20 years ago we were firmly in the single-mode (on or off - no low power option), incandescent generation, which meant 20-30 minutes runtime on $6-$10 in batteries. Nobody carried Surefire that I knew.

Even today 123s are too pricey to be any kind of enticing for someone pulling 3rd shift.

I was working 3rd shift as a security guard back those days. Batteries were murder on my little budget, but I bought them anyway, and I even got the M6 Guardian (although it mostly pulled shelf queen duty). Those were the glory days of Surefire and my 9P rode faithfully on my hip for several years.

Seems like the batteries were a little cheaper then. Like $1.25 a piece? Or was it $1.50? That's still $3 for one hour from a 6p, or $4.50 from the 9P.

Didn't mean to hijack the thread. I never had any safety issues with 2 x CR123 or 3 xCR123 configurations. I love my li-ons today, but I did have a thermal runaway event with a new cell on a charger earlier this year.

As far as reliability, the hot wire was the weak link in the chain back then.

 

[zipplet]

Re: Reliability & Safety - 1x18650 versus 2xCR123a -are Surefire/Elzetta right?

Reasons I feel that people consider using only 2x CR123A for reliability reasons in critical situations:
- Battery internal resistance and ability to deliver at maximum output is unknown unless you look after your cells carefully (many people will not), CR123As from a reputable brand have repeatable performance every time
- Protection circuit can fail with shock
- Protection circuit might kick in if extreme power is drawn momentarily due to abuse, CR123A will not suffer from this issue and the risk of overheating is accepted in military/etc use (can be an issue with certain incandescent lights)
- Swapping in fresh primaries is easier and quicker than swapping in rechargeables
- Even if you carry spare rechargeables, if you swap batteries you are carrying "dead weight" - I suspect some personnel will dispose of used batteries in the field ( ) etc