Mounting your battery pack is highly recommended. Mounting will prevent the battery from moving while on the water putting unnecessary strain on the electrical connections. It will also ensure you keep your electrical system up out of the bilge and away from any potential saltwater ingress.
This mast mount from BerleyPro is designed specifically to mount the Lithium battery packs from FPV-Power to the internal mast receiver present in most Hobie Kayaks. This mount suits the FPV 7ah and 17.5ah Li batteries. Made in Australia from black ABS plastic with stainless steel fasteners provided.