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A 10-Year Battery for AirTag

(www.elevationlab.com)
673 points dmd | 1 comments | 18 Dec 24 18:17 UTC | HN request time: 0.2s | source
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janandonly ◴[18 Dec 24 18:19 UTC] No.42453230[source]▶
That is not how batteries work. Batteries drain even under minimal usage.

My bet is that in 2/3 years this device will stop working already.

Just change the batteries if you AirTag once a year. Especially if you are using an AirTag to keep watch over 10.000 dollar equipment.

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alnwlsn ◴[19 Dec 24 00:17 UTC] No.42456978[source]▶
Here [0] is the datasheet for the batteries used. 25 year shelf life is spec'd.

I have personally run these cells buried underground, and gotten 4.5 years out of 4 of them, though my application is just for fun and likely not as power conservative as an AirTag.

[0] https://data.energizer.com/pdfs/l91.pdf

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01HNNWZ0MV43FF ◴[19 Dec 24 19:32 UTC] No.42464912[source]▶
Ooh what's the application underground?
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1. alnwlsn ◴[19 Dec 24 20:39 UTC] No.42465499[source]▶
So I attend this local annual event that has a time capsule. Each year, we bury one and dig up the one from 5 years ago. This has gone on for several decades, and people are always thinking of interesting things to put in there.

I made a little electronics project that is somewhere between "what happens inside a time capsule while it's buried?" and "what if you could wind a watch once and have it still be ticking in 5 years?"

I nearly forgot that I made a project page for it: https://hackaday.io/project/160740-low-power-environment-mon...

I dug up the first one last year and it had made it to 4.5 years, and I'm actually due to dig up the second one next week.