Taking care of the electrical system is pretty important. On my previous car, I ran on a bad battery for a while, along with bad belts. This resulted in an overworked alternator. The overworked alternator ran very hot, thus allowing the belts to expand and eventually fall off. I went through several drive belts with this problem. I then replaced the alternator, but the problems continued. The alternator relay had gone bad too, from running with a bad alternator (although a new battery and belt were in place). Afterwards, I replaced the relay and the problems went away. This is just to tell you that unattended problems can result in a growing pain = $$$$ out of your procket.