When my laptop battery are failing they no longer accept large charge currents. They only accept very little for a short period of time before charging stops.
A new laptop battery sucks much more amperage for longer before tapering to zero. Bigger gas tank requires longer to fill.
I am on my 4th replacement laptop battery with the correct tools to monitor laptop electrical consumption.
I use a DC to DC converter. I rarely bother with an inverter for anything, and certainly not for powering this laptop.
Right now it is pulling 70 watts with a 80% charged battery. With fully charged battery this is between 35 and 43 watts. If laptop battery were below 505 it would be pulling 85 to 95 watts
When the laptop battery is failing with a 20 minute maximum runtime or less, the laptop never pulls more than 49 watts
