What do you do when you have plugged the ipod in and it says no battery power connect to power?

The wire has to have a very good connection, for instance I can plug my charger into my laptop and my laptop doesn't recognize that it is plugged in, If I don't have a can of compressed air then I blow in the end of my charger and blow in the computer where I plug the charger into and sometimes that works but keep in mind you have to blow pretty hard, compressed air works better. I guess that the dust can keep the cable from getting a connection. Or your cables could be bad.