Little story! Since i am not driving the 3 too much, I had recently been getting a battery pic light up on the dash. My Canadian Tire trickle charger fixed that in one day, going from below 50% charge to fully charged the next morning. That makes 2 battteries saved so far for me, 4 if I count my neighbor's and my brother's who borrowed it at some point. Oh, I hooked it from the engine bay, no need to go in the trunk....
/little CT story