I use the B&D VEC1093DBD 40AMP SMART MODE PORTABLE Charger. I also have a small (name I can't remember) 2AMP trickle charger. I also carry a good 12-foot long (home made from aircraft starting flexible cables) jumper cables for my truck.
My Battery system consists of 255Ahs of capacity, My on-board converter/charger is a smart mode PD9260C 60AMP unit, my generator is a 2KW Honda EU2000i...
My camping plan revolves around doing all we want to do camping off the power grid in a one day/night run off the batteries and re-charge the next day starting at breakfast for around three hours with the 30AMP trailer Shore Power Cable connected to my 2KW Honda Generator 120VAC receptacle using a RV30A-15A Adapter.
In order for us to re-charge our three 12VDC batteries to a 90% charge state in a quick three hour time span we have to have 14.4VDC Charging Voltage and around 18-20AMPS of DC Charge capacity for each battery. Having less DC current capacity will charge the batteries just fine but takes many more hours to do it.
Most often we camp in places that have generator run time restrictions in place so getting my batteries re-charged in the fastest time possible is our primary goal. Been very successful over the past 5-6 years doing just this...
Just now starting to think about SOLAR PANELs to supplement my battery charging requirements with the thought in mind to reduce the need for running the 2KW generator as much.
Hopefully I have all my PLAN-Bs covered...
My batteries were installed in late 2008. Following the golden rule to never let out batteries drop below 12.0VDC (Approximately 50% charge state) and re-charging to 90% charge as soon as possible is our reason for good battery life. We also observe that doing the 50% to 90% also requires a full 100% charge state after around 12-14 charge cycles. This will require a good 12 hours of charge time using the smart mode chargers.
My battery charging story - I'm sure others do it differently but this is what has worked very successful for us over the past few years.
Roy Ken