Pulsar@lemmy.world 1 day ago
I bought Xtar rechargeable AA just for the deadbolt cause I got tired of replacing enveloops every few weeks. They last a long time, but when they drop to 1.1v the deadbolt stops working. So, battery level is always 100% until the day the lock doesn’t work.
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!
Pulsar@lemmy.world 1 day ago
Not exactly, my schledge deadbolt has zwave so I can monitor battery percentage in HA. The problem is that the Xtar is a constant voltage rechargeable lithium battery with a constant 1.5V output. They drop to 1.1V to signal low charge. When that happens the deadbolt stops working soon after.
hereiamagain@sh.itjust.works 1 day ago
Does 1.1v not signal low voltage? How long does it work for after that? Could you set up an alert so that the moment it changes you get a text message? Or a light turns red or something?
Just curious. I haven’t played with HA, though it’s a long term goal.