How's everyone's [55Wh] battery health and wear looking?

[anarcat]

@anarcat

Here’s my rendering of the battery right now, after slightly less than a year of use:

And here’s the graph, almost two years later, after less than 3 years of use:

You can see it never went back up to 100% after those drops, but the capacity oscillates between 78% and 88% in march. Here’s a zoom of the last month:

@Charlie_6

I found the answer, the “drop” is likely due to the BMS deliberately lower the limited charging voltage after some time or cycle to use only a part of your battery’s capacity, this makes the user think the battery has degraded. The motivation of this is yet to known. If you have the opportunity could you please fully charge your laptop and read the voltage(while still plugged in)? If that voltage is significantly lower than 17.6V(such as 17.4V), then this is the exact problem. My 61Wh battery decided to “degrade” 9% by limiting the voltage from the original 17.8V to 17.6V. The same 0.2V drop is witnessed here(55Wh, 17.6~17.4V).

anarcat@angela:~> cat /sys/class/power_supply/BAT1/voltage_now
17380000

I guess that’s 17.38V? And would confirm your hypothesis. The battery is not fully charged right now though, I’m at 93% and charging, will try to remember to update this post when it’s fully charged.