Comment by aftbit
7 hours ago
No, there's basically no reason you'd ever want an alkaline battery except cost. For your use case of long-term storage or a rarely used flashlight (e.g. in a car emergency kit), you'd want a Li/FeS2 as the parent poster recommended, also called just a "Lithium" primary (i.e. non-rechargable) cell. They have a longer shelf life, don't leak, hold more energy, can provide a higher discharge current, work over a wider temperature range, and have safety characteristics very similar to alkaline.
There is one very good reason: the discharge curve. An alcaline battery loses voltage when it discharges, the lithium ones discharge with the max voltage until they suddenly stop working.
This is a reason insulin pumps require specifically high quality alkaline and lithium is considered a risk.
Lithium primary cells have a shallower discharge curve than alkaline, but not completely flat; measuring state-of-charge is essentially trivial for any competent design engineer. Medtronic specifically recommend FR6 lithium cells in their insulin pumps.
https://data.energizer.com/pdfs/l91.pdf
https://www.medtronicdiabetes.com/sites/default/files/librar...
Main disadvantage is cost. Looking on Amazon, it's $1.61/ea AA lithium vs $0.62/ea akalaline. That's Energizer vs Energizer. Amazon Basics AA alkaline are $0.32/ea. (Unlike alkaline, knock-off lithium aren't much cheaper than Energizer.)
If I had a dollar for every device that I've seen ruined by leaking alkaline cells, I could buy a palletload of lithium cells.
Well how many batteries do you need as long term storage for emergency use? $10 worth?
Everything else use rechargables for a dollar-ish plus charger cost.
Great point.
I was going to say cost is a really significant factor there, but I was thinking convenience retail where they are marked up. They are only 3x more on Amazon. Now you're guaranteed to damage equipment as the current alkaline formulations leak.
There are a handful of applications where alkalines are better. IR TV remotes run effectively forever on a couple of batteries and the slow self discharge on the alkalines makes them ideal for the task.
Great in theory.
In practice, the Duracell alkaline battery will leak caustic fluids inside the remote control and destroy it, and you will have to mortgage your house to buy a replacement on eBay, if it's even available. (I pick on Duracell because they are the worst. They leak if you look at them wrong, when they are brand new, inside the original packaging, before their "expiration date". But all alkalines are bad.)
All my remotes get NiMH batteries, no matter what. I don't care if one charge cycle lasts 10 years. It's cheaper than having the battery destroy the remote.
I've only had batteries leak in remotes left unused for over a year. I just pick up Duracell or whatever is at Costco.
I've also bought two replacement remotes off of Amazon in the past year, one Samsung and one Insignia. I think they were $15-20 each, which seemed very reasonable to me.
Generally they won't have the manufacturer's logo, but everything else on the outside looks 100% identical, and all the buttons worked.
I have never, in my 40 years of life, had an alkaline battery leak and destroy something. I'm aware that it can happen, but in practice it doesn't happen very often.
2 replies →
I think you're thinking of rechargeable Lithium-ion batteries. GP is talking about lithium primary cells, which have even lower self-discharge than alkalines. Usually about 1/2 the self-discharge rate of alkalines.
That's an interesting counterpoint, thanks for letting me know. I was really under the impression that lithium ion batters discharged more aggressively. Maybe that's just more reflective of how they lose capacity over time? Can you speak to the fire risk?
The comment above is about non-rechargable lithium-metal batteries. You are thinking of rechargeable lithium-ion batteries.
Lithium primaries are great. I use them in my weather station. 2AAs have lasted at least 4 years, and still work well when it's 0F out.