How to clean magsafe 1 port black pin

Hi… I have an old MacBook Air 2011. It isn’t charging well and noticed one of the magsafe (T shape) ports pins on the MacBook is black. I assume is from electrical arcing. Is there a preferred method to clean the pins. I tried a bit of rubbing alcohol and a soft tooth brush but it still looks black (that solution works well great for cleaning iPhone lightning port). I didn’t want to brush too hard so as to not break a pin.

Would electric contact cleaner get rid of the black and is do is it ok to use apply it while the battery is connected?