CTEK MULTI US 7002 12-Volt Battery Charger – Link 
This has currently dropped to just $82.49 on Amazon – It’s lowest ever!
This is highly rated with a 4.7 star rating.
- Unique 8 step charging system with a patented program that tests battery condition and, charges and maintains to ensure maximum battery life and performance
- No sparks, short-circuit proof and reverse polarity protected makes it safe for all the vehicles electronics and easy to use
- Charges 12-volt lead-acid batteries (Wet, MF, Gel, AGM and Ca) from 14Ah to 150Ah (charging) or 14Ah to 225Ah (maintenance)
- Maintenance pulse charging increases battery life and gives superb performance, and patented de-sulphation functionality allows for the recovery of slightly sulfated batteries
- Water and dust resistant means it is safe to use in all climate situations
- Includes two interchangeable connection leads, one with clamps, and one with eyelet terminals
- Eight step, automatic switch charging and four separate charge modes that together allow for easy, convenient, no-watch battery charging