Remember Duracell’s PowerCheck? The idea was that a strip built into the battery would show if the battery was good or not. Sure, you could always get a meter or a dedicated battery tester — but PowerCheck put the tester right in the battery. [Technology Connections] has an interesting video on how these worked and why you don’t see them today. You can see it below.
Duracell didn’t invent the technology. The patent belonged to Kodak, and there were some patent issues, too, but the ones on the Duracell batteries used the Kodak system. In practice, you pushed two dots on the battery, and you could see a color strip that showed how much capacity the battery had left. It did this by measuring the voltage and assuming that the cell’s voltage would track its health. It also assumed — as is clearly printed on the battery — that you were testing at 70 degrees F.
The temperature was important because the secret to the PowerCheck is a liquid crystal that turns color as it gets hot. When you press the dots, the label connects a little resistor, causing the crystals to get warm. The video shows the label taken apart so you can see what’s inside of it. The resistor isn’t linear so that’s how it changes only part of the bar to change color when the battery is weak but not dead.
It is a genius design that is simple enough to print on a label for an extremely low cost and has virtually no components. PowerCheck vanished from batteries almost as suddenly as it appeared. Some of it was due to patent disputes. But the video purports that normal people don’t really test batteries.
Watch out for old batteries in gear. Of course, if you want to really test batteries, you are going to need more equipment.
I probably still have one of these testers at home. I peeled it off the battery and attached 2 wires to it with a small screw and nut. I used it as a universal AA battery tester :D
I have a stash of them somewhere too, I used to cut them off as a kid
We have yet to see 7-segment displays made from batteries, or a “battery” clock made of multiple ones. Chances are we never will.
it’s the same thermochromic ink we’ve seen people play with before. https://www.youtube.com/watch?v=ZWmmNFp-Oh4
I did make it into an analogue HDD usage meter.
By plugging it into my HDD LED connector on the mainboard on my pentium :)
It had built-in hysteresis :)
Now that is a cool hack!!
This person understands how to conjure up hacks on the internet. Well played!
Just drop the battery on its tail on a hard surface, if its flat it bounces, if its full it goes thud. Alkaline only.
I wonder how far this method could be taken accuracy wise.
We could attach a vertical clear tube to a small granite (or other very flat and hard surface). Calibrate with a new battery. Then drain that battery against a constant resistance, and continue testing and marking until it is completely dead.
We now have a completely mechanical battery tester. We could perhaps automate by adding a microphone and performing an FFT on the thud sound. This could be turned into a phone app with calibration routines built in (such things already exist for testing the authenticity of silver and gold coins — and they work well enough to tell you exactly which silver coin you are dealing with).
None of this is practical but it’s fun to think about.
See my response above, the bounce only indicates if the battery is brand new or has some power drawn from it.
“So while it’s true that dead batteries bounce, so do half full batteries, and even 99% full batteries. All this test can really tell you is whether a battery is brand new or not.” https://www.mcgill.ca/oss/article/did-you-know-general-science/do-dead-batteries-really-bounce-and-charged-ones-not
I love my 1.5 V AA-USB-C-loadable cells. They have a light that blinks blue/green/red, depending of what cell the chinesium seller has.
Just saying.
I still keep some from 9V (6F22) packages- they were not on battery due to size, so it was easy to peel them off the cardboard. :) That build was a bit different, as it had three crystal zones in parallel with different width.
I wish this was available for NiMH AA.
I wonder if it could be made to work with the much flatter charge curve of NiMH.
It would certainly have more utility in that application, and the higher per-cell selling price leaves a bit of room for the added cost.
I never liked to use the built in tester.
It was clear that they worked by heating the strip. Heating the strip would require a fair amount of current, so testing your battery would also discharge the battery.
I never saw much point in running my batteries down to see if they were run down.
The best way to test a battery is under load.
It’s apparently using about 1 ampere. So a 5 second check would use 0.05% of capacity.
Testing any battery is going to “drain” it. Testing uses very little energy, even a test strip that heats crystals
A load is a load to a battery.
That was a generally good video but that dude waffled far too much. Just get on with it and practise your generic humour at the local open-mic. Maybe I’m being harsh, it is far from the worst waffle that appears on “tech youtube”.
Yup. He used to make some interesting videos (even if his jokes were somewhat unfunny) but I removed his bookmark some time ago exactly because of that. Trying too hard and becoming narcissistic instead of just showing tech.
I guess being on the feedback loop and obeying the mighty algorithm does that to people.
I don’t think it’s anything to do with that, but if you think that of his channel then almost all channels are going to be no better. And humor is subjective, of course. How do you feel about, for example, techmoan?
I think what it actually is may be that you just aren’t looking for the parts that do exactly what this guy’s channel name suggests. That is, his purpose is making tech connections, or in other words he’s not trying to give an exhaustive look at exactly how it works and nothing else – he’s trying to show the gist of it while drawing connections to a broader context, and he’s trying to make that accessible to as broad an audience as reasonable. Sometimes he links or separately uploads extra detail that he couldn’t fit into the regular video. I’ve generally been impressed at how well he manages to make things that both you and your much-less-tech-oriented family member could get something out of. As a different example, I never looked inside the mechanism of a door closer, and didn’t need to know every single thing about it, so his video on those was a reasonable watch for me. I could always skip ahead or use 2x speed if there was a section I was bored by.
In this case, it’s a shorter video since the way the tech works is pretty simple albeit a clever idea, and there were only a few other things to talk about after covering that. Though, look how many people in the hackaday comments still missed even that basic idea? The gauge doesn’t drain the battery that much just using it for a few seconds, but it does tell you a better estimate of how well the battery is doing than just checking the open circuit voltage, and it is very simple to make.
He was fine with his videos but the guy took his schtick too far. It’s called jumping the shark and when these idiots do that is when you check out if you have a brain. Happens with TV shows, youtube creators, filmmakers, actors. The only creators it doesn’t happen to are the ones who never go full-retard for attention.
If you just want to see weird old tech then go to a Goodwill. His jokes may not always land, but to claim what he’s saying is “waffling” is to simultaneously not understand what he is saying and at the same time believe you already understand everything you need to know. In which case I ask, why are you listening to the waffling? If you only want to know the “how” and ask no more questions, then just skip to where he explains the tech and go on.
Although, I will say, narcissistic projection is a very real phenomenon.
That’s his schtick, you certainly don’t have to like it, but it’s what you can expect. Like many YouTubers he’s developed his approach over the years, making it a product of feedback from his audience while trying different things out, and he’s refined to a consistent style, which obviously works given his subs and view counts.
Don’t watch it :)
He targets tech non-savvy but curious people (another video about Pelletier coolers shows that well). What you consider “waffling” is a necessary extended procedure to introduce civic majors into the topic.
In USSR there was a series of books similar in style about “disassembling” stuff like machines or toy, without actual disassembly. It was targeting curious kids and teens or young adult, both keeping them out of harm and educating them.
what happened to batteries not leaking ?
Mercury, prevented batteries from leaking.
https://www.epa.gov/mercury/mercury-batteries
Technically, a valve would have been better so the gas from the alkaline reaction could escape instead of increasing the pressure on the cell’s chassis and finally leaking.
Mercury WAS the valve. It’s actually a type of precise valves, simply mechanical one wouldn’t work. Not it’s just labyrinthian and some produces doesn’t make it correctly
They always could leak. It was formerly prohibited to advertise the battery as ‘leakproof’, but his regulation was repealed in 1997. q.v.:
https://books.google.com/books?id=WrQV1RcK0VAC&dq=%22leakproof%22+%22federal+trade+commission%22&pg=RA1-SA7-PA8#v=onepage&q=%22leakproof%22%20%22federal%20trade%20commission%22&f=false
I’m 75 years old. Never in my life has there been a time when batteries did not eventually leak. That includes regular carbon-zinc cells, alkaline cells, and nicads.
I used to buy only Duracell because they had an anti-leak guarantee (used it a couple of times). No longer, and they are now quite prone to leaking in my experience. I now use Energizers, which seem to be better sealed.
You aren’t kidding. We stopped buying them a few years ago as we had sooo many of them leak long before they were depleted, sometimes even in the package (months old and many years before their “best by” date or whatever they call it). We always bought them in large quantity packs at the big box stores since we were going through so many back then. This wasn’t a rare occurrence. It got to the point where a significant percentage of each package was pretty much guaranteed to leak before we finally switched brands.
Funny thing about this article: I recently pulled out an old piece of electronics that I haven’t touched in years only to find it had one of these Duracell batteries with the gauge on it (I was shocked, didn’t realize just how long it’d been). I’m usually pretty good about taking batteries out of electronics when storing them, so this was especially surprising. The most surprising part was that this long-dead battery did not leak! They really did change a lot since they made them with the gauges.
I wonder how many other people have stopped buying them for the same reason. Even the cheap Amazon or Publix store branded batteries are better than Duracells these days.
They produced at different plants, quality can vary. Also, if that was a standby circuit (no physical break), it got less chance to leak. They leak because they slowly discharge through themselves!
Oh, and there are plently of bootleg Duracell around. I just recently came by ones which look like Quantum… but the tester is a FAKE. No indicator strip.
I suspect it’s made in Iran. The label and package looks good enogh but there is a pressence of weird language stickers, etc.
Newer battery formulations allow for a 10 year shelf life. That’s what made these testers obsolete. You really only needed to test unused batteries. Otherwise they sit in whatever device until they are dead.
Leaking is caused by that slow self-discharge going past zero capacity. It can still happen if you leave spent batteries in a device for years, but now that it’s cost effective to have 50 spares on hand you’ll change dead batteries.
This was available in Germany, too, but the strip that I remember was external. Late 90s, I think.
It was a paper-like strip included in the battery box that you would manually attach to both plus, minus contacts of your Mignon/AA battery.
What’s also interesting, maybe:
The AA batteries seemingly got a bit thicker at the time
and had problems to fit into older devices from 80s, 70s and before.
Maybe that’s another reason the power strip had disappeared?
Batteries that get stuck in a battery department are no fun.
That’s why some compartments came with a strap.
Hmm, now you mention it I recall those as well, in the UK. They seem farther back into the past than the ones built into the cells themselves. What I don’t recall is the tester in the packaging actually working, it felt somewhat like a practical joke. Whereas the ones on the cells did seem to work with some portion of reliability and honesty.
Glad you summarized it for me. I wanted to watch the video when I saw it the other day but he goes on and on and on for far too long. That should not have been a 20 minute video.
That’s one of his shorter ones…
You are aware that you can speed up the video, right? He basically sounds identical at 1.25x speed, and is still clear at 1.5x
It was in fact about 14 before closing remarks, which can be sped up to 7 if you feel he’s talking slowly.
The genius of the design was that it discharged your battery, so – you had to buy another battery!
Every time you wanted to confirm that the strip was still properly calibrated, you needed a brand-new battery!
True. But I’m not sure if this was even intended here.
A resistor or incandescent lamp or magnet is among the simplest circuits, each, simply.
And each consumes batteries as quickly as a first gen Gameboy, unfortunatelly.
A real power meter uses an high impedance coil for the gauge,
which is the very opposite to an low-impedance resistor that heats up.
In the real electro mechanical meter, there’s 50 micro amps needed for full scale or something.
It’s basically nothing in terms of power (current).
50 uA at 220 kV is enough to power approx. 80 000 homes. Power transmission lines operate at high tension but very little current to minimize losses due to ohmic heating of steel cable.
Might want to double-check the math there. 50µA × 220kV = 11W
LOL 11W not even enough to charge cell phone
Pretty sure you can charge a phone with much less then even 5watt. It’ll just take longer. Also charging slower is even better for the battery!
Steel power lines would be unusual. A strong but ductile aluminum alloy is common, as is aluminum for conductivity wound with steel for strength. For specialty uses there are things like copper clad steel.
Indeed, due to the skin effect the current only travels through the outer copper skin, so the inner core needs strength not conductivity
That’s inapplicable to alkaline batteries. Electromechanical voltmeter would only show that battery isn’t completely dead and is not shorted inside. You need correct passive load at particular current to figure out if it’s ok or not. As you increase resistance, the voltage would rise near to their nominal volume. Under load it may drop to a fraction if volt.
I remember there being a strip supplied with the Maplin Electronics catalogue (or perhaps if you placed an order over £5) that did this, long before I saw it embedded on AA batteries. Probably around 1984? Very clearly two tapered conductors on the back so giving the increasing resistance away from the centre point, so the wider the thermochromic section colour change, the greater the voltage. I burnt mine out testing it on things way more than 1.5V…
Without knowing the discharge-characteristic of a battery, measuring it’s capacity is going to be impossible. Especially because the characteristic differs per battery. If a battery is not rechargeable, there is no way to measure its discharge-characteristic. Because by the time you know the characteristic, the battery is dead. :)
Proper chicken-egg problem, for non-rechargeable batteries.
Only thing you can do, to give a user feedback on the sate of the battery, is to measure the voltage of the battery regularly, and give a warning when it reaches some level that is too low for your device to operate. But for some types of batteries, the warning will come in time, while for others it will still be too late.
I don’t know, maybe someone can confirm this here. Some devices specify that you should only use an alkaline battery in them. I used to think that was because alkaline batteries had a slightly higher voltage. But that’s not true, they’re all around 1.5V +/- 0.05V.
So, did they actually specify alkaline batteries because their battery warning light/gauge was tailored to the discharge-characteristic of alkaline batteries, and would give false warnings when zinc-carbon batteries were used? ;)
You can measure the internal resistance of the battery. The battery circuit is like a perfect voltage source with a variable resistor in series. Since you know the voltage source (that’s what you measure without a load or an infinite resistance load thus zero current), if you measure the actual / physical battery voltage over a known load (thus the impedance of your circuit), you can deduce the internal battery resistance. Most testers simply estimate a constant load for the circuit, thus the voltage drop across the internal resistance is a mirror of the battery health. You don’t need to do this way, if you know better the expected load. The internal resistance will progressively increase as the chemical reaction is depleted but you can interpolate the curve and know if and when the battery is dying.
The no load voltage of most batteries varies with the state of charge.
They specify alkaline batteries because carbon zinc has a higher internal resistance and can not supply as much current
I’ve worked a little too long with parts of the manufacturing and packaging industry to believe that patent squabbles or “users don’t bother with them” were the final straw in the decision to drop this feature. The several cents per label (and specialized printing for the larger particulates) would be my first guess, and battery customers look at price first, though they shouldn’t (leaks cost you more than any battery set), so the added feature and added cost/price didn’t equal sales increases in a slowly shrinking market.
Good article in Vice detailing some of this: https://www.vice.com/en/article/why-the-battery-power-meter-was-way-more-controversial-than-it-looks/
You basically just described “users don’t bother with them” in more detail. The manufacturing process was certainly not free but it was cheap enough for Duracell to give it a try. But they found that it wasn’t pushing sales, presumably because most consumers didn’t care, and stopped.
No. The consumers didn’t selectively purchase the brand because of them, whether they “bothered with them” (used them for their intended purpose) or not, They purchased based on price. The feature’s costs were not recouped in maintained/increased share of a shrinking market, so any cost-added items were dropped. The CPG world is full of clever innovations that suffer a similar fate, usually blamed on “consumer disinterest”.
Again, you just described “users don’t bother with them”, good job. They were an added cost that didn’t push sales, as consumers look for the cheapest option in the market and any bells or whistles are wasted profit margins. A company did a thing differently that costed money and no new sales happened so they stopped, it’s the literal definition of consumer disinterest. If the extra 2¢/battery for the tester made them more sales then they would have kept it.
Still available
https://amzn.eu/d/cjJ7oxx
IIRC, Radio Electronics (or maybe after it was renamed to Electronics Now) had an article using the battery tester off of a blister pack as an RF wattmeter.
Spoiler – beyond the patent fights, they had no value to most users of batteries who keep new batteries in their blister packs and simply replace batteries in use when they fail.
The tester was really only useful on new batteries. Before 10 year battery shelf life with the date printed on your battery, you really didn’t know what “new” meant when you grabbed a battery from the pack. You might throw out the device when trying stale batteries to follow the dead batteries.
Never seemed to work consistently either. I would get a completely different reading than my spouse etc. Or it would say it was near dead when it wasn’t because I had too much resistance.
Neat idea but good riddance.
Haven’t had to buy batteries for years just get some rechargeable Nimh and save $$$
or even better – li ion
One problem I had was was when you put them in a mini maglite it pushed on the two buttons and kept the strip alive and the battery went dead.
Took a long time figure out why my batteries were going dead all the time LOL
That reminds me, I have a 2xAAA Maglite that needs its batteries drilled out.
Wow, two nights ago I was looking at a couple of batteries and wondered why they didn’t have the checker anymore. Where is my Fluke.
I wrote to the company saying that I had stopped buying their batteries ’cause the only reason why I paid their high prices was the testing strips. The response I got was that most customers found the expiration date on the package adequate for their purposes. I was dumbfounded by their response, never figured how an expiration date told me how much life was left in the battery. I bought testers and have bought cheaper batteries ever since.
They’re still available from Duracell. I use them daily. They come in bulk, not for retail sale packaging. “Professional” or something similar on the batteries. If you’ve got an account to order medical supplies, they’re available.
Did it really say normal people do not test batteries? 🤔🤨
Unless someone can get batteries for free I’m going to test everyone of them till they are in the red before I throw them out.
AAs. Go from toys, to tv control, to wireless mouse, to clock, before they get thrown out.
Just down grade them on the power needed for each devices.
Bluetooth remotes tend to drain them a bit quicker though. Lol
Eh i used my tongue since i was 7, lick a finger, put on the flat side, the plus side on the tip of my tongue. If its tingly its fine, but please dont do that with a 9volt, youllbe shocked of the result.