Battery level fluctuating wildly

[cwdev]

I haven't done any hardware testing with the voltages, but my battery does the same. It never goes above 34% while plugged in, and when it's not plugged in and just running on battery power, it drops immediately to 4% and slowly times to around 20% - but the phone enters a near unusable state.

I'm just running the manjaro/plasma out of the box install, updated before use, but I have no taken much time to mess around with anything else. It looked daily driver ready while it was plugged in but it seems borked when it is not.