Both bathroom and kitchens scales are large enough they can run on AA / AAA batteries and casually go a decade (or more) without replacement.
Tangentially: I used to have a 3 button timer, it was a little LCD countdown display and 3 buttons. One button set hours, one minutes, and one starts / stops the countdown timer. I found this timer when I was a kid, used, and the 1 AAA battery it had lasted into adulthood, literally decades. I have since bought almost the exact same device - 3 buttons, one display - a few different times and the newer ones only last a year on the same battery.
What's going on here? Presumably someone designed a new 3 button timer, since they can't just steal an existing schematic, and I guess just nobody cares to make it good? Why don't all 3 button timers last multiple decades on a AAA battery?
I've seen the same thing with other small electronics, like the dozen or so stopwatches I've owned in my life. A few of them go strong for decades, others have their LCD display start fading in a year.
> Both bathroom and kitchens scales are large enough they can run on AA / AAA batteries and casually go a decade (or more) without replacement.
For bathroom scales, sometimes the design doesn't permit batteries larger than button cells, since the entire scale is a piece of tempered glass with four 1/4" tall feet and a lighted LCD display that shines through the glass. I like this particular design because it's thin enough to fit under a door as it swings. Batteries in my scale last over a year with near-daily use, and mine has a very bright display.
My relatives have a similar type of bathroom scale.
When the button cell ran out, I popped in another one we had lying around.
One month later, the button cell was dead, after using the scale a handful of times. Obviously something was draining the button cell battery when the scale wasn't in use.
I could try and debug the scale, but given that even ten minutes of investigation would be more than the amount of time I spent using the scale in one year, I just decided to remove the button cell when the scale wasn't being used.
Two years later, that button cell still works in the scale...
I buy a lot of those little timers for my business. They get pretty heavy use, maybe running timers for about 6 hours per day. They don't last anywhere near decades for us.
Anyway, my insight is simply that some of them turn off the LCD after a while of non-use, and some of them keep it on indefinitely. Maybe that explains the difference between your two experiences.
The timer I had never turned off the LCD. I found it in early elementary school and the same battery was still going strong when I got married in my late 20s. So it lasted 15+ years on a single AAA battery.
I had the same exp. One I bought in the mid 90s. That original battery that came with it lasted nearly 10 years. Then another 5 with the new battery. I retired it when the plastic casing came apart. The LCD never turned off. That thing was a tank.
The newer ones I am lucky to get a year out of the battery. Even using the on/off switch.
I've noticed something similar with remote controls. Receivers, CD players, DVD players, Blu-ray players, TVs, cable boxes...almost every one I've ever bought came with batteries that lasted for many years. Sometimes longer than the device the remote controlled.
Then, when the remote needs new batteries and I put in the batteries sold in US stores they would last a year or two.
The batteries that came with these devices were brands I'd never heard of and never seen at any store in the US. Usually they had lots of Japanese-looking writing on them and little English except for the brand name.
1) The OEM battery was probably fresher than the one that wound its way through retail distribution and then sat in a drawer at your house for longer than you realize
2) By the time you have to replace a battery, your remote's PCB has had time to adsorb water and contaminants from the air, get soda spilled on it, etc and is going to have higher leakage. It will then always draw more current in standby.
Batteries are sold with an expiration date on the package, and I don't think that's usually decades out.
In the 80s I remember seeing expiry dates on AA packs of 99, and my child-brain thought they didn't expire so they put a meaningless number there instead - I couldn't process the idea of the year 1999.
I've had the opposite problem. I was reading a lithium battery package many times, frustrated that I could not find the expiration date. I finally realized that "2032" was printed as a year and was not an alternate size code.
But 10 years is also the rated lifetime for CR2032 cells. Those made in 2022 will definetly still be good to use in 2032. I've had some last as PC CMOS ram backup cells since the late 90's and they are not rechargeable, nor being charged in the system they are in.
Sounds like nearly decades to me if buying in 80's and have an expiration of 99... Just because a childlike brain of hours can't understand that sort of time doesn't mean it's not literally decades.
That's asking for corrosion damage from the battery.
I've got a bathroom scale that goes several years on it's pair of coins even though it turns on only when stepped on. I suspect there's a physical switch involved, though.
why don't they use gravity as the power source? I've seen scales that require pushing a button several times to power it. Getting rid of the button and using the full scales' surface seems like the next step.
IIRC it's not really the build quality, it's the new limitations around chemical composition inside the battery. I'm not sure about non rechargeable lithium batteries, but I think alkaline leak more and last less due to mercury getting phased out. Some newer Li-ion cells might also suffer from having less and less cobalt inside, due to high cost and supply related issues. Both are good trade offs, especially since alkalines are probably on the way out and manufacturers are getting better at making lithium batteries without cobalt
I have a digital LCD clock, a giveaway by NTT from a trade fair, that still works with the same single Maxell AA battery since 1998. The battery quality must have been amazing at the time, or the clock uses almost no power. I honestly don't know how that's possible. :D
Ine the same way designers discussed above try and big dick their designs, clocks when through some EE big dicking on trying to minimize battery usage. Same thing with LCDs.
They got them to really low power usage. Some of the ones today would basically last your whole life on a single button cell.
I have this ultracheap made-in-China big kitchen clock, with a single AA that I've replaced twice in eight years. I don't buy expensive batteries, more like in line with the clock.
It has second hand (the kind that doesn't tick but appears to move uniformly) so there is some extra mechanical work.
I think the quality is hit and miss, even with premium batteries. I had enough devices damaged or entirely ruined by a leaked battery so now I remove them from anything not actively used.
If anyone knows a reliable model for AA/AAA cells that will absolutely not leak when left unused in a device for year+ I would love to hear it.
I’ve had much better experience with energizer not leaking while Duracell is terrible. Searching the net for other experiences, I found some prepper forums discussing this and apparently Duracell tries to extract so much capacity from the cell they sacrifice wall and end thickness causing them to leak.
I don’t think anyone can say they absolutely won’t leak, but search these types of forums/subreddits and you find other recommendations as well.
We switched to buying USB-rechargeable AA/AAA lithium ion batteries. The brand we buy is Pale Blue, but there are many other brands.
These batteries have a regular form factor, with an added micro USB (and USB C on some larger battery sizes) port for recharging. They work really well for us and charge quickly (and conveniently — everything has a USB socket nowadays).
The price may seem expensive, but after 10 or so charge cycles they should have paid for themselves. I expect these batteries will be good for many hundreds of charge cycles.
I wouldn't recommend this personally, having had bad experiences with poor charge circuitry in integrated chargers like these (in my case it was in a 18650 battery). Get a good charger (e.g. eneloop), and then you can get generic rechargeable batteries incredibly inexpensively for it, without risking poor charge management causing overheating or battery failure.
The same little charger circuit built into the batteries also converts the lithium battery chemistry voltage to 1.5v making them a drop in replacement for AA and AA batteries.
Or are you saying you can get 1.5V lithium rechargables that work with an external charger?
Get IKEA's LADDA rechargeable NiMH, they are a rebrand of Eneloops, the some of the highest quality NiMH batteries available, and are made in Japan; all tests on YouTube and elsewhere consistently put them at the top of the line.
They have very low self-dishcharge rate (and even come precharged in packaging) and with recharge cycles ranging from 500 (for the highest capacity 2450 mAh AA ones) to up to 1000 (for 750 mAh AA/1900 mAh AAA ones). Also, they do not leak.
Big Clive suggests using nimh batteries for expensive electronics since they won’t leak. Also they are much better than they used to be, and there are many slow self-discharge brands that you can actually buy pre charged.
My solution for this sort of thing is the rarely-used devices get lithium cells. More expensive but they're not prone to leaking once they're discharged.
Tangentially: I used to have a 3 button timer, it was a little LCD countdown display and 3 buttons. One button set hours, one minutes, and one starts / stops the countdown timer. I found this timer when I was a kid, used, and the 1 AAA battery it had lasted into adulthood, literally decades. I have since bought almost the exact same device - 3 buttons, one display - a few different times and the newer ones only last a year on the same battery.
What's going on here? Presumably someone designed a new 3 button timer, since they can't just steal an existing schematic, and I guess just nobody cares to make it good? Why don't all 3 button timers last multiple decades on a AAA battery?
I've seen the same thing with other small electronics, like the dozen or so stopwatches I've owned in my life. A few of them go strong for decades, others have their LCD display start fading in a year.