Coin Batteries and Temperature-Induced Malfunctions

[JRV]

I’ve done a 180 recently on red dots, which sucks… because they’re fantastic shooting tools.

We are finally getting cold snaps here. Long story short, I had to go to court one morning when I wasn’t expecting, so I locked my carry gun (P365XL/Holosun 507KX2) in my glove box for a few hours. When I returned, the slide was cold to the touch (air temps in the mid-30s to low-40s). Checked the optic… and no dot. Would not respond to any button presses. Off, and soft-locked off.

Removed the battery, warmed it up, reinstalled, good to go. This was with a fresh Duracell 1632.

Did an experiment overnight with my P320/Romeo1Pro and a Glock slide with an RMR06 mounted. Let them get icy cold overnight on my balcony.

Both optics were soft-locked. The Sig was still at a usable setting, but it would not change settings until I warmed the battery up. The Trijicon was extremely dim and would not change brightness until I uninstalled it and warmed the battery. Both had fresh Duracell batteries.

So, I’m basically off optics that run on coin batteries unless it’s a dedicated home defense gun that stays warm. Anyone else have a similar experience?

[GJM]

I carried a P1 Acro last year for a week of elk hunting, out all day in temps down to -20F without windchill, and had no dot problems. Carried AIWB and in an exposed ALS.

[GJM]

Not sure if a factor, but I have been using Renata batteries.

[JRV]

I carried a P1 Acro last year for a week of elk hunting, out all day in temps down to -20F without windchill, and had no dot problems. Carried AIWB and in an exposed ALS.

I’ve been mentally pushing myself to the P2 instead of writing off dots altogether. I know Aimpoint knows how to insulate a battery and circuit for all conditions, because our patrol rifles had zero issues regardless of temperature. I also imagine battery placement away from the mass of a freezing steel slide helps…

With the Trijicon, the battery was a sealing plate away from a chunk of freezing steel. The Sig faired better in my unscientific experiment, and I’m hypothesizing (probably without basis) that was due to the top-mounted battery.

[JohnO]

I've seen published data that states:

The optimal operating temperature range of Lithium Ion Batteries is generally limited to 15–35 °C (59°F to 95°F).

[JAD]

I've seen published data that states:

The optimal operating temperature range of Lithium Ion Batteries is generally limited to 15–35 °C (59°F to 95°F).

Coin cells are lithium, not lithium-ion; nonrechargeable, not rechargeable. They have a significantly wider temp range than LI (also, that quote is pretty tightly boundaried). However, all batteries gain resistance when cold. That means voltage drops faster than when warm, which means less power is available. That’s a circuit design problem — the designer should have known it and taken it into account.

[Default.mp3]

FWIW, the Holosun HS507K X2 has a published operating temperature range of -20 °C to 51 °C/-4 °F to 124 °F.

An older product sheet (from 2012) showed that the RMR adjustables had a published operating temperature range of -40 °C to 49 °C/-40 °F to 120 °F. Couldn't find anything on the newer Type 2s.

Didn't find anything on the Sig optics.

Aimpoint claims -45 °C to 71 °C / -49 °F to 160 °F for the ACRO P-1.

[MickAK]

There are reasonable expectations out of equipment and unreasonable expectations out of equipment. Someone posted recently about how this isn't a hobby, and if a piece of equipment requires a machinist to work it's not equipment, it's a hobby, and since life and death is involved it's not a hobby to them.

When we add complexity to our equipment, we take on the responsibility of understanding how that equipment works. Whether it's mechanical stresses or electrical circuitry the takeaway from failures isn't necessarily that the equipment is faulty but that we installed the equipment without doing the necessary background work on how that equipment functions.

It takes a pretty minimal amount of insulation to ensure that electrical circuitry will function in cold temperatures, and we put a good amount of heat off of our bodies when we carry. You can manufacture electrical circuitry to function without such insulation but in a pistol application it carries other drawbacks.

I haven't seen that issue myself. There are a number of small disposable chemical warmers that would alleviate it if the optic can't be stored in a manner that retains heat and you need it to function absolutely when retrieved from a cold space.

[frozentundra]

I've had the opposite experience.

I live as far North in WI as you can get; we are in one of the few places in the lower 48 that is designated climate zone 7.

I've used these types of batteries on rifle sights, both in LPVO and micro dots, in extremely cold weather (-20s F ambient temp), and I can't personally recall an optic having acute and sudden battery death due to cold exposure. I try to do most of my winter shooting practice in somewhat warmer temps-I often wait for the warm days with highs above 0 or in the teens-but I've spent a lot of time sub-zero with rifle optics (not pistol optics).

I'm not saying it can't or doesn't happen, but I've personally never noticed it on my rifle sights.

I've had a old Primary Arms micro dot with failure of the shake awake system and intermittent battery connectivity issues, but that didn't seem temperature or battery dependent. That is the only failure of an electronic sight that I can recall having in the last 15 years or so.

I think I've mostly used Energizer Lithium in the past before recently ordering a pile of Duracell. I'll be sure to test if the newer ones have trouble in this regard. Thanks for the heads up!

[WDR]

The one and only time I had a dot "fail" for me, so far, was an Aimpoint Micro in cold temps (low teens) and high winds (wind chill) with a old (more than a year old) Energizer battery. The dot was there when I got out of the warm truck, but it was not very visible 30 minutes later when I threw the gun up to shoot at a running jackrabbit. I always keep a couple of spare batteries on the gun, and swapped it out in about a minute. The underside he the LT-660 mount has room to fit two, sealed in plastic. The fresh, but cold-soaked battery worked 100%.

For the record, I usually would change the batteries in this optic every January 1st, and it lived most of its life set at setting #7 or #8, sitting ready to repel boarders in my gun locker at home. I had purposely not changed it, and took it out in the cold as some what of a test to see what would happen. IMHO, it validated my normal procedure of changing batteries with the new year. Fresh battery during the coldest part of the year makes sense to me.

I have yet to notice any problems with RMR'd Glocks kept in the cold. I'll probably do some experiments when it gets real cold in a few weeks, just to see what happens. I've fully converted to using Duracell 2032's in everything now, after reading a bit about batteries in other threads here. I have had other troubles with Energizer 2032's in things like garage door opening remotes, and kids toys. So far I've had way better luck with the Duracells.