Jerry - had a similar problem with our 2013 Ford Explorer. Started carrying a 12 volt jump starter (similar to this one:
https://www.amazon.com/Booster-ES500.../dp/B000JFHNQA). BUT I changed the battery (came in the SUV and was 40 months old) and have not used the jump starter since.
Just our experience.
PS: the problem with the battery going dead was I lost the brakes applied by my Brake Buddy.