Back in 2016, I wrote a daemon that grabbed the system battery stats every second and dumped it into a CSV.

I ran it on my laptop for 99 days:

Major takeaways:

  1. Cheap replacement lithium-ion batteries have a really limited number of cycles.
  2. Linux laptop power management still has a ways to go.
  3. Pulling battery stats and writing a file once per second isn’t great for power management.