This is just an opinion.... The battery does a very good job of stablizing the voltage. So if you place a capacitor bank in parallel to it, the capacitor back is rendundant. Better place the capacitor bank across the load with a short-as-possible wires. This capacitor bank will tend to minimize the resistance (hence voltage drop) of the wires from the battery to the load.

Electrolytic capacitors are very good in filtering low frequency variations. But for high frequency noise, it is not so good. Ceramic capacitors are good for high frequency noise but due to it's low capacitance is bad at low frequency noise. So it is best to parallel this two types of capacitors.