I would install it parallel to the battery. So + on the capacitor to + on the battery, - on the capacitor to - on the battery. You're describing a series connection which won't work at all. In retrospect, I probably shouldn't recommend it. It's not at all necessary for a working system, but I like the belt & suspenders approach. It's really best for cheap dual sport kit battery packs. Otherwise, just put your time and money into a better quality battery.