Adnan, I have used a cheap 12V 4Amp battery charger for about the last 30 years and I've had no problems with it. If you can afford it though, you might want to get a CTEK charger. I work away from home, so my cars have been known to sit in the garage for 3, maybe 6 months unused... If you're charging the battery, it's best to disconnect the battery from the car - if you have a garage, there's no need to remove it - just leave the bonnet open. If you expect the car to be unused for a long time, then it's best to remove the battery and bring it into the house. When you want to use the car again, charge it overnight, before putting it back.
