Rashi peripherals — HP Laptop Battery

I had bought HP laptop battery from vendor named as Three Ess Computers. But battery was faulty and stop functioning after 3 months. The warranty period was 1 year. When I contacted Three Ess computers, they asked me to get it replaced from Rashi Peripherals. Rashi Peripherals accepted my complaint and promised to replace the faulty battery.

After 5 months of proloned wait and reularly approaching them, they asked me take the faulty battery back and that too they gave my battery of other make i.e. Compaq. When I said its not my battery they told this is your battery and we do not any more entertain my request and asked me contact Three Ess Computers back.

I would like to file a case against Rashi Peropherals.... please advise