Hello XXXXX'm Chris, a current Ford Lincoln Mercury employee.
Thanks for visiting Just Answer. I will do my very best to help you resolve your concerns.
Your concerns are associated with a alternator charging then not charging so its intermitent or the battery connections are poor at the battery or there termination or the alternator connections are poor. Sounds more like this is a concern with the alternator or wiring to it since a vehicle will run with a dead battery.