Hello,
Me again.
So I have an LG battery it has been experiencing similar problems and based on this thread I've made some observations which may help some people.
In my case the battery was undetected and would not report power level or anything else.
Since the most recent firmware (which I struggled to install) when I finally got it on, it made no difference. . .
This was until I powered my surface on without being plugged in from sleep mode. This resulted in the machine detecting my battery.
When I plugged it back into the wall it returned to not being able to detect my battery and then once again after putting it into sleep, unplugging, then powering on later the battery is detected and properly reporting level of charge. I may later see if
I can plug it in and have the system continue to properly report that it has been plugged in.
For anyone else struggling (whose surface has enough charge to unplug without shutting down), you should try plugging it in, putting it into sleep, waiting about ten minutes then trying to bring it back up to see if that makes a difference.