Yes it is recommended, wrap the battery with a thin foam (1/4") is usually enough, the receiver is the main thing that needs to be wrapped in foam, which insulates it from the vibration of the engine, be it nitro or most importantly gas. Spongy foam is negligible in weight and will provide the proper amount of vibration protection both the battery & receiver need. If you have room for the little box that Great Planes has, it is really great. Part Number GPMM1010, available from Hobby Shop or Tower Hobbies.