The 12V smart battery system of your Spaceship allows you to run internal items, like the fridge and USB ports on the car battery. It protects the battery. It's like having a second car battery. The battery won't go flat. It's a closed system, with no plugs, and no connections for outside items or devices. It charges when you are driving and it powers the internal items when the engine isn't running.

You can use the fridge and use USB ports at night. No worries. The smart battery system will protect the battery so you can always start the engine again in the morning. As you'll be driving again the next morning the system will fully charge itself again so you can use it again the next evening/night.