I am trying to revive an original iPad Air (that we though was dead). It charges brutally slow, like 15% a day slow and only goes to 55% max. I was thinking about changing the charging port but with the soldering required, I think I am going to pass. Do you think changing the battery will help? (I am assuming ff it charges, albeit slower than molasses, does that mean it's the battery and not the port?) Any advice would be appreciated!