cross-posted from: https://slrpnk.net/post/21299422
My kitchen scale is powered by a cr2032 lithium button battery. Yes, it was sloppy of me to buy the scale without seeing how it was powered. I only use the scale once or twice per month, yet these shitty button batteries only last a few months. It seems like I only get about ~6—12 measurements before the battery is dead.
WTF? This seems to defy physics. The scale automatically powers off. Of course it must always have some power because there is no ON switch. The scale detects capacitive touch taps or weight before turning on the display.
Digital calipers use a button battery which also only gives a dozen or so measurements before the battery is dead. It seems the calipers power on when the case is snapped shut. Maybe the rattling causes it to power on since it’s very touchy. Turns on with the slightest movement.
My bicycle helmet takes a cr2032, which only lasts a few months. Perhaps because it’s hard to remember to turn off the light. But still, it’s a shitty design because it has no timer or motion sensor. Or would a motion sensor itself use more power than the LEDs?
Questions:
- are button batteries a significant e-waste burden?
- are the batteries themselves really short lived, or are the appliances that use them all just poorly designed?
If there’s no on/off switch, it means it just goes to sleep and never truly turns off. Low power mode is nice for people who forget to turn things off, but it’s still draining the battery to monitor the sensors, so it doesn’t make a lot of sense for something that’s not used frequently.
The calipers remind me of my earbuds, which are always jostling in the case and disconnecting from the charging pins. I can be in the car and my music will suddenly stop playing on the radio because my earbuds came loose, connected, and took bluetooth priority. It’s irritating, and if anybody has a fix, let me know.
My kitchen scale that runs off of one of those batteries lasts for years, and I use it every day (coffee). Yours must have some kind of parasitic draw.
You could possibly mitigate the problem by keeping the battery out of the scale except for the few times you use it. Or add a snippet of tape you peel off and replace. Will the battery for the calipers fit in the case separately? It would be a PITA but so is constantly replacing them.
i might try this for the calipers. But the battery cover for the scale uses a screw… so i might opt to hack that to use external power of some kind.
We had a kitchen scale with a damaged control panel - the on/off button stopped working. I opened it up, cut one of the battery wires, and soldered in a switch. Cut a hole in the case with an xacto knife, glued the switch through it and put it all back together. Now it has a hardware power switch. If you’re comfortable with basic soldering, maybe that would work for you?
Seems like a good approach for the scale. It’s quite thin but I’ll see if I can add a mechanical switch.
