Battery voltage question: is 13.7V enough to charge an AGM battery - BMW 1 Series Coupe Forum / 1 Series Convertible Forum (1M / tii / 135i / 128i / Coupe / Cabrio / Hatchback) (BMW E82 E88 128i 130i 135i)
How to Test Your Auto Battery | Battery Testing & Maintenance | Autobatteries.com
Charging lead-acid batteries – BushGeek
Battery Chemistry Battery Charging Module – Sterling Power Products