Actual risk when using primary lithium instead of alkaline?

[TacmedRN]

Hey All,

I want to put a couple "backup" lights in my "go bag" in the event of a power outage or emergency.

Even if the lights have rechargeable capabilities, I want to be able to keep some lithium primary cells as backups in the bag so I don't have to worry about alkaline storage issues.

Along with a Streamlight Protac 1L-1AA, I want to put a Streamlight Microstream and Stylus Pro in the bag. I confirmed with Streamlight CS that the latter two lights are NOT designed for use with primary lithium cells.

The AAA lithium primary cells I am looking at are advertised as 1.5v, which is the same as AAA alkaline. I'm looking at the Energizer Ultimate, if that matters.

If the voltage is the same in the lithium vs. alkaline, why is Streamlight so insistent that the lithium primaries NOT be used? What is the actual real world risk?

 

[thermal guy]

If you're going to store batteries in your light they must be lithium batteries.alkalines will leak and ruin your light. They may mean 3.7 volt lithium rechargeable batteries are not to be used.

 

[TacmedRN]

If you're going to store batteries in your light they must be lithium batteries.alkalines will leak and ruin your light. They may mean 3.7 volt lithium rechargeable batteries are not to be used.

I confirmed they meant primary lithium cells, and they even said "like the energizer ultimate lithiums" in their statement. They couldn't really tell me WHY I couldn't use them, just kept repeating that their lights "were not designed for non-rechargeable/primary lithium batteries."

I'm probably going to use lithium anyway, but I just want to know if there is any REAL downside in actual use. Will my light overheat? with it fry the LED? stuff like that.

 

[elzilcho]

I've never heard this from SL (not saying they didn't say it to you--their CS sometimes seems to be quite disjointed) and have used primary lithiums in my Microstreams for years and years. Never had an issue with them in different SL lights and I've seen no downside to using them.

 

[aznsx]

What is the actual real world risk?

You've succeeded in confusing the Hell out of me (not that it's that difficult to do of course;-)

Based on your previous thread, I was under the impression that you had several different lights which failed catastrophically / terminally within days of simply switching them from alkaline cells to lithium primary cells (presumably Energizer L91/92?), with no other stated changes or variables involved. If so, you have empirically proven that what SL is telling you (incompatibility w/ lithium primary cells) is true. If you've proven for yourself that what they're telling you is true, why are you questioning it? It would seem you've established (unfortunately) that the 'actual real world risk' is very high.

I may have seriously misunderstood your original thread, and if so, I'm sorry 'bout that. Perhaps you can straighten me out so I can possibly try to help, but right now, this isn't making sense to me.

 

[F89]

Sounds silly to me that lithium primaries aren't advised or even work. Relying on alkaline alone is a known leak liability.

Out of the packet a decent AA or AAA alkaline is around 1.6V while a lithium primary, 1.8V.
I've never owned a light that used the above battery types and couldn't use lithium primaries, and I'm talking about lights that aren't lithium ion compatible.

 

[TacmedRN]

You've succeeded in confusing the Hell out of me (not that it's that difficult to do of course;-)

Based on your previous thread, I was under the impression that you had several different lights which failed catastrophically / terminally within days of simply switching them from alkaline cells to lithium primary cells (presumably Energizer L91/92?), with no other stated changes or variables involved. If so, you have empirically proven that what SL is telling you (incompatibility w/ lithium primary cells) is true. If you've proven for yourself that what they're telling you is true, why are you questioning it? It would seem you've established (unfortunately) that the 'actual real world risk' is very high.

I may have seriously misunderstood your original thread, and if so, I'm sorry 'bout that. Perhaps you can straighten me out so I can possibly try to help, but right now, this isn't making sense to me.

Yeah, I can see how it would be confusing. I'll clarify.

After posting here and Reddit, and having conversations with some of my techy friends, I came to the conclusion that there was something wrong with either the lights or that batch of batteries.

I bought new batteries and plan on buying new lights. I just want some idea of what I should reasonably expect rather than whatever fluke I experienced.

 

[F89]

Any decent light deserves a lithium primary or rechargeable NiMH. They'll both perform better than alkaline without the risk of leaking.

 

[aznsx]

Yeah, I can see how it would be confusing. I'll clarify.

After posting here and Reddit, and having conversations with some of my techy friends, I came to the conclusion that there was something wrong with either the lights or that batch of batteries.

I bought new batteries and plan on buying new lights. I just want some idea of what I should reasonably expect rather than whatever fluke I experienced.

Thanks for clarifying. It sounds as if you have already concluded that the info SL is providing is incorrect / misguided, and I was not assuming that (and am still reluctant to at this point). In any case, your course of further testing will yield more data points, and that may well provide the end of the story - or part of it at the very least. Please let us know, especially since I believe these are fairly popular lights, so others may benefit. BTW, I'm sorry you're experiencing this, regardless of the root cause. It's a pain at the least, especially if you depend on your lights in your work as I often do. Stuff like this is why we carry backups;-)

 

[TacmedRN]

Thanks for clarifying. It sounds as if you have already concluded that the info SL is providing is incorrect / misguided, and I was not assuming that (and am still reluctant to at this point). In any case, your course of further testing will yield more data points, and that may well provide the end of the story - or part of it at the very least. Please let us know, especially since I believe these are fairly popular lights, so others may benefit. BTW, I'm sorry you're experiencing this, regardless of the root cause. It's a pain at the least, especially if you depend on your lights in your work as I often do. Stuff like this is why we carry backups;-)

I'm still not sure they are giving me misleading information so much as I am hopeful they are just being conservative.

I agree many could benefit from more study on this, if I had the time. Working 60 hours a week while taking care of a 3 year old and another kid on the way leaves me with less than a tiny bit of free time, haha.

 

[thermal guy]

If you own a light that can take 1.5 volt alkalines but will not accept 1.8 volt lithium batteries toss that sucker away. I've never heard of such a thing.

 

[vicv]

Ya. Either way the light is using a boost circuit. Unless it's using 3 in series and relying on ir to limit current. But if it's the latter, toss the thing anyway

 

[JimIslander]

Those kind of lame battery shenanigans put me off of foursevens flashlights permanently. No excuse for that lack of flexibility.

 

[TacmedRN]

Ya. Either way the light is using a boost circuit. Unless it's using 3 in series and relying on ir to limit current. But if it's the latter, toss the thing anyway

I'm a noob when it comes to flashlights. Can you translate "boost circuit" and "3in series relying on it to limit current" please?

 

[F89]

Basically a driver that boosts the voltage (1.5V to the ~3V LED voltage in this example).

Three in series (batteries end to end, voltage increases with each battery. In this example it would be 4.5V).
The ir part is referring to internal resistance (to limit current). I'm pretty sure that's what vicv meant?
Expanding on that, relying on the internal resistance of the batteries etc to reduce the excess voltage to what the LED wants which would be less than ideal and why vicv said to toss the thing if that were the case.

That opens up more questions regarding drivers that buck (reduce voltage) and drivers that can both boost and buck.
I'll leave it there though, clear as mud?

Anyway I reckon vicv is correct in saying that your light would have a boost driver (ups the voltage from a single 1.5V AA to the LED voltage of around 3V).
Therefore a lithium primary at 1.8V would be perfectly cromulent to use in your light.
No worries.

 

[Kitchen Panda]

Those kind of lame battery shenanigans put me off of foursevens flashlights permanently. No excuse for that lack of flexibility.

I don't have the pamphlet handy, but my Four Sevens Quark AA seemed quite happy for years on lithium iron disulfide (Energizer L91) for most of a decade before I switched to rechargeable NiMh. I think the Quark pamphlets said Li Fe S2 was OK but straight disposable 3V lithium primaries were not allowed (though the Quark AA used the same head as the 2AA so that's probably why...3 V OK, 6V no good).

 

[F89]

Just read the original post again. I was focusing on single AA which from what reading isn't the issue.

So the issue is the 1xAAA and 2xAAA lights.
I can't see why the 1xAAA should have a problem.
The 2xAAA without any details that make it obvious doesn't sound like it should have a problem either (with lithium primary 1.8V cells).
If it is the case that neither of these single and double AAA lights can handle 1.8V lithium primaries I'll add my vote for the toss it in the bin/never buy camp.

 

[F89]

This got me intrigued so I had a look at the Streamlight website.
The Protac 1L-1AA sounds good and versatile. They list 1xAA alkaline or lithium and CR123A so roughly a 1.5V to 3.2V input voltage, also handy how it manages to accommodate the different size of the batteries.

Sure enough the Microstream and Stylus Pro only mention the use of alkaline batteries.

I also see mentioned above that you've already killed one of each of the lights in question by using 1.8V lithium primaries so that's that.
I don't know what to say about that except I think their drivers are super crappy in that regard and I wouldn't ever buy those lights. I also wouldn't recommend that you buy them again but if you do, as you've learned and they've told you, don't use 1.8V lithium primary batteries in them. Which of course is mad because why on earth would you want to rely on a potentially leaking alkaline battery that either doesn't work and/or has destroyed the light when you need to rely on it?

On the other hand you could swap out batteries (daily?) or not keep them installed in the light. This obviously is a pain and completely goes against your intended use as an emergency light that you just need to grab and have work instantly without issue.

I'm not completely adverse to using alkaline batteries but definitely not in lights on a general basis and the idea that Streamlight would make these lights completely dependent on using them is absurd to me.

 

[Toulouse42]

I agree with the other posters here. Any modern flashlight that can't cope with a single Lithium AA is not worth owning. Its an example of poor design.

 

[fuyume]

There are still many devices out there for which the manufacturers have explictly stated not to use lithium iron disulfide primary cells. While there are a number of reasons we could speculate about, given the electrical differences between them, none of them are verifiable without the word of the people who designed these devices. Lithium primaries have been on the market for decades, so there's really no excuse for this in 2024, but it still happens. I've lost or damaged too many valuable pieces of equipment over the years to ever use alkalines in anything important/expensive/irreplaceable ever again. For anything that gets carried on my person, I use lithiums only, just for the weight savings.