How to wire 6V Batteries in series or parallel configuration
Schumacher Electric Schumacher Pro Automotive 6-Volt/12-Volt 8-Amp/2-Amp Battery Charger and Maintainer with Auto Voltage Detection SPR1628 - The Home Depot
Amazon.com: Battery Charger Automatic 6V 12V 1.5A, Trickle Charger Suitable for AGM Gel SLA VRLA Flood Lead-Acid Batteries, Starting Batteries for Auto Car Motorcycle, Dual Voltage Output Detection and Repair : Automotive
How to charge two 6V Lead-acid batteries with 12V pulse charger (Two battery charge in series) - YouTube