Why Trailer Breakaway Systems Need Their Own Dedicated Battery

Updated 04/22/2020 | Published 04/21/2020

Question:

Can you upgrade the battery to a full size car battery so a person could also run auxiliary items in the trailer, ie lights, etc. Or is there a way to charge an additional battery using the 7 pin trailer connector?

asked by: Andrew D

Expert Reply:

Breakaway batteries shouldn't power other accessories even if the battery is larger. You really need the breakaway battery to be topped off at all times in case you need it. If you were to power other accessories you run risk of it being discharged in an emergency and it not able to work like it needs to.

Typically people run two batteries for this. The breakaway like the # 20099 and then a deep cycle battery for everything else. Topping off the batteries with the 7-way circuit is possible still as you'd basically just run the 12 volt circuit to both batteries.

expert reply by: Jameson C