Battry not Recognized after Liquid Spill

Had you looked around you could find many possible answers here. No amount of cleaning will cure physical damage. You have either missed corrosion spots, or more likely, the liquid blew out components on the board.

I know of no way other than the Mark-1 Eyeball & and a magnifier to identify swollen or shorted (burned) components. This is a very advancedl DIY project. Desoldering and soldering of logic boards requires special tools, solder and lots and lots of practice. Unless you have much experience and knowledge in small electronic/computer repair IMHO it's a job best left to a professional. There are vendors on e-bay who claim to repair/remanufacture damaged logic boards.

You can remove and replace the logic board (an advanced DIY repair - difficult but not as impossible as repairing a damaged board). It requires complete disassembly and reassembly of the entire computer.

Same with the keyboard replacing the top case assembly (easy) or just the keyboard (masochistic) are the two solutions to your key problems.

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