Auto Restarting Problem

[fdkk]

my phone just started restarting automatically at the samsung logo,took it to samsung service the they took my hand set only without the battery. they said they have fixed it ,but the moment i put my battery in and switch on the phone it happens again,when i change the battery to another one(at the samsung service center)it works without any problem.should i spend 35 usd and buy a new battery? or could it be another problem?i am currently using the phone with my old battery as i found out that it switches on and works fine when i plug in

PS;Battery is about 15 months old