We have frequent issues with centrally supplied hot water, so I made a simple monitor with #ChatGPT and @arduino Nano Matter. It checks if hot water pipe is cold and if so - turns on electrical heater. Otherwise it keeps heater off with #HomeKit (or #HomeAssistant thanks to #Matter).

Takes only 0,07W - will work for weeks on two #18650s 🙌.

Here's a #GitHub link:
https://github.com/in-sympathy/hotWaterMonitor

P.S.: someday I'll get it a proper enclosure, though this looks cool to me as well 😊.

I dismantled a few old laptop #batteries tonight. Ended up with bloody thumbs and a small pile of #18650s

Working my way through testing, but what can I do with them?

Got a new toy - 18650 battery tester, so checking if my spare batteries are up to specs.

Also testing 3 Samsung cells that I found inside of my accidentally burned Goal Zero Venture 30 power bank - while I’m waiting for a replacement IC to arrive why not check if the batteries should be replaced as well 🤷🏻‍♂️.

Love the fact that I can just plug in any 4 batteries into this tester and see what they’re capable of 👌🏻.

#electronics #electronic #18650s #repair #electronicsrepair #18650battery

#Batteries question:

18650 #Lithium batteries are often described with the chemistry type as e.g. ICR, IMR, IFR where the cathode is generally the middle of the three letters.

I have some *ISR* #18650s which I may have to replace.  I haven’t found a detailed reference.

(The cells are available internationally but possibly not inUK and there may be a reason?)

I know there’s a Lithium/Sulphur battery type but it’s new; these are 5+ years old.

Any ideas what the S could be?

#18650battery

Me: I won't need more than one or two #18650s

Also me: I now have eighteen 18650s on my desk.