If you're going to be keeping your RV or camper van in storage for a long time or simply plugged in at a campsite, you’ll want to take advantage of that power source to keep your auxiliary battery charged. There are some systems that have the ability to both power and top off your batteries from shore power but they tend to be fairly expensive and if you've pieced together your own power system you might be looking for a way to save some money. For my build, my shore power system was pretty basic: just a NOCO AC port plug and a heavy duty 12 gauge extension cord. I also chose to run the AC port plug that had two AC plugs so that I could run one end to a power strip inside the van and the other end to this NOCO onboard charger to keep my 200 amp hour lithium battery topped off when plugged in.
This charger is a 10 amp one bank charger (hence 10x1) that runs off of AC power and it has charge profiles standard lead acid, agm, as well as lithium batteries. It is primarily designed for boats and other marine craft to keep their batteries topped off in storage but it'll work perfectly for camper vans and RVs as well. It's very simple to set up after you've installed an AC port plug, Just plug the AC cord into the port plug and connect the positive and negative wires to your auxiliary battery. Then Set the charge profile to your particular battery’s chemistry (lead acid, gel, agm or lithium). Once that’s done you are off and charging.
Utilizing a simple system like this will maintain the life of your auxiliary batteries and make sure that you're always starting out a trip at 100%. Here's a simple list of the components needed to piece together this kind of system.
12ga Heavy Duty Extension Cord (50ft)
200ah Lithium LifePo4 Battery *Obviously you can use what ever battery suits your needs and budget. This is the one I used in my system and although it's steep in price, it provides great value for features, construction and longevity.