Comment on Tired of expensive disposable batteries and rechargeable AA suck. So I made a 10k mAh pack for my deadbolt.

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hereiamagain@sh.itjust.works ⁨1⁩ ⁨day⁩ ago

If I’m thinking correctly, that’s because the xtars die at 1.1v, but the lock still thinks that’s plenty of juice so it reports 100%?

But normal AA are 1.5v… weird. I guess they aren’t dead dead until .8 or. 9v, but still.

Assuming you’re using 4 batteries, that means the lock is seeing 4.4v and not reporting a low battery, because real alkalines would go down to 3.2v or 3.6v.

So what you can try doing, is adding a small diode in series with the positive lead of the battery. A schottky would get you .3 to .5 ish voltage drop, bringing your 4.4v down to 4.1 or 3.9v, which would probably be enough to trigger the warning?

Or if you went for a regular rectifier diode at .7 to 1v drop, you could bring that to 3.7v or 3.4v, which would put you right in the zone of normal batteries dying.

Diodes are cheap, it’s worth a shot!

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