An Ionic Polymer Metal Composite Based Electrochemical Conversion System in the Ocean

Abstract

In the ocean, there are a wide variety of offshore plants, and these stand-alone plants require electrical energy. Turbines can be used to convert ocean kinetic energy into electrical energy but these turbines are fixed structures, which are not advantageous. Electro active polymers are playing an important role due to their electricity generation characteristics corresponding to mechanical stimuli. Piezoelectric materials have long been used to turn kinetic energy into electrical energy. Although they have showed remarkable electrical energy generation in several applications, their brittleness and response characteristics only to high frequency stimuli limit their various applications. The use of ionic polymer metal composites can be a solution to overcome the drawbacks of piezoelectric materials since ionic materials are soft and they better respond to the low frequency stimuli. Moreover their intimacy with water enables them to be used in water environment, which is fit for ocean kinetic energy harvesting. However, they show low energy generation density per unit area when compared with other energy sources. In this study, an ocean kinetic energy harvesting module has been constructed and operated with newly developed graphene-based ionic polymer metal composite as an electrochemical material. The module can be relocated to accommodate certain applications to efficiently capture both vertical waves and horizontal ocean currents to supply electricity to stand-alone offshore plants. The module produces electrical energy over the target of 120 Wh and up to 600 Wh for 20 days. Since then, the growth of algae and barnacles on the module retard the electrochemical material's motion and disrupt harvesting of the electrical energy. The ocean kinetic energy harvesting module has the potential to coexist with marine environments and represent an advance toward the sustainable utilization and development of marine resources.