They are used to keep the 12 volt battery topped off. If you are storing a car for a long period of time they do counteract the drain the battery see's from the computer and other small draws that are always there. One problem with putting these on an Insight is the fact that the 12 volt socket doesn't come alive until you turn the key to accessory so it wouldn't do anything unless you hooked it directly to the battery. As far as the 144 volt pack, I wouldn't mess with it. The car keeps track of the SOC by monitoring what goes in and out while the car is running. If you were to change this while the car is sitting then you would mess that up and start experiencing many SOC recalibrations.