battery swollen replaced now magsafe only charging 50% of the time.

Macbook pro mid 2009 had since new. No water damage etc

Recently mouse pad stopped working and this was due to swollen battery.

New battery put in (not by apple)

Worked fine for a few weeks but then started saying battery needs service and now says it needs replacing

At same time magsafe has become unreliable only sometimes lighting up and others not. New battery discharges really quick over a few hours only and macbook wont power up on AC only without the battery

No warranty of course.

It this the logic board or has swollen battery damaged something?