I have one of these and it’s still going after almost 19 years. Why is this battery tech not used in other things?
It is used in other things. The key to your question lies in the fact that you’ve hardly used it. What you’ve observed is essentially the shelf life of the battery.
My guess is that they combined a small lithium battery (like a CR2032) with a very intermittently used LED light.
So you get extreme shelf life (15-20 years) combined with very, very little draw on the battery from the light.
Polaroid is, of course, out of business (The current “Polaroid” is legally distinct from the old company, and doesn’t service the old one’s products), but until a few years ago you could obtain the equivalent flexible PolaPulse batteries from other manufacturers. Now, alas, that has ceased as well. I had a flashing bike light that used one of those batteries.
This site, however, claimsd to still have them:
http://users.rcn.com/fcohen/Polaroid.htm
You can also find batteries on eBay:
I have a small, digital travel alarm clock that’s had the same AAA Duracell battery in it since I got it in 2000. The alarm is used daily. The expiration date on the battery is 2004. I don’t think I’ve ever had a battery last so long.
Huh… apparently I was wrong. The PolaPulse batteries were developed to power the SX70 cameras (which were powered by these batteries in the film packs), and even there, were more than what a typical film pack needed. They’re a sort of flat, flexible LeClanche zinc chloride cell.
So they’re probably just total overkill for a little tiny LED light, which probably needs tiny voltage and current to actually work. I doubt the battery would work for powering a Polaroid SX70 camera by this point though.
In my experience, battery life is tied more to the device the battery is in than the battery itself. Put batteries in a cheap plastic flashlight and they will be dead in a month, even if left unused. Put the same batteries in a good Maglite and they last for many years.
That’s sort of how it works… but only if your device has a constant current draw.
All normal batteries (i.e. not thermal ones) have a finite lifespan- basically they self-discharge at some tiny rate even when not being actively used to provide current. For your average ca. 2016 alkaline battery, that lifespan is roughly a decade under normal conditions. Lithium batteries have an even longer lifespan- like 15-20 years, unused, and can provide more power overall and/or keep the voltage up (I don’t recall exactly WHAT they’re better at) longer. They’re overall better than alkalines, but you pay for it.
Zinc chloride batteries are typically the shortest lifespan- maybe 2 years. And they don’t provide much energy either, but they’re super-cheap.
Apparently the Polapulse batteries have a longer than listed shelf-life, and the flashlights probably draw so little juice that they don’t significantly draw the battery down, nor do they need much battery capacity left to continue to work.
zinc chlorides… these have the electrolyte soaked into Manganese Oxide … it hasn’t got the charge density in it for use in place of lead acid or Li ion.
These Polaroid flat packs don’t have metal encasement, its the metal which fails on the AA,AAA, B,C,D metal cells…
Duracell might have had the bright idea to plastic coat theirs at some stage… seems that one is … a long lasting version…perhaps it was sold as such.
You do realise that Duracell, Energiser, etc, sell based on peak performance (runs your high power draw device for longer.) rather than Amp Hours (which is how to measure performance for a low draw usage ) or shelf life …
(BTW, you’d think government would regulate … to ensure that such things met minimum shelf life… that would save the environment wouldn’t it ? )
Basically , the alkaline cells can produce the Amp Hours (or if voltage is changed too, you can measure the charge in Watt Hours, or Volt Amp Hours for ease of comparison ) even when the draw is high… the thing is the Zinc chloride’s waste the power if the draw is high, you see ? if you drain higher current out of the zinc chloride’s you don’t get the rated Amp Hours…
So the zinc chloride was fine for the hand held torch use… Not so good for powering your room or street light. (the total size would have to be huge, and then you are wanting rechargeable to avoid having to replace such a huge thing every week … )
I had a toy called a “glow worm” that I got when I was nine months old. The batteries may not have been original, but they weren’t replaced for at least 20 years, and still worked. But all it did was light up when you squeezed it, and the light itself was rather weak. And it hasn’t been used much in those 20 years.
If that can happen to plain Duracell batteries, it could easily happen to others build differently.