Electric Eel Biomimetics for Energy Storage and Conversion

Abstract

The electric eel is known as the most powerful creature to generate electricity with a discharge voltage up to 860 V and peak current up to 1 A. These surprising properties are the results of billions of years of evolution on the electrical biological structure and bulk, and now have triggered great research interest in electric eel biomimetics for designing innovated configurations and components of energy storage and conversion devices. In this review, first, the bioelectrical behavior of electric eels is surveyed, followed by the physiological structure to reveal the discharge characteristics and principles of electric organs and electrocytes. Additionally, underlying electrochemical mechanisms and models for calculating the potential and current of electrocytes are presented. Central to this review is the recent progress of electric‐eel‐inspired innovations and applications for energy storage and conversion, particularly including novel power sources, triboelectric nanogenerators, and nanochannel ion‐selective membranes for salinity gradient energy harvesting. Finally, insights on the challenges at the moment and the perspectives on the future research prospects are critically compiled. It is suggested that energy‐related electric eel biomimetics will greatly boost the development of next‐generation high performance, green, and functional electronics.

Carbonized Cotton Fibers for Ultrahigh Power-Density Electrokinetic Energy Harvesting

“…The fiber mimicking surface structure in a MD unit cell with dimensions 25 × 22 (lateral dimensions) × 16 (transverse direction) was considered for the model simulations, where the length units were normalized using the LJ parameter σ for the modified carbon atoms. The number of water molecules in each simulation cell was adjudged from the density of water at 300 K. The wall atoms were tethered to springs with sufficiently high spring constants, to eliminate the possible unwarranted artifacts of a mechanically rigid system in recovering the true slip length values from a dynamic data set . The Simple Point Charge/Extended (SPC/E) model was used to define the water molecules and their interactions …”

“…The number of water molecules in each simulation cell was adjudged from the density of water at 300 K. The wall atoms were tethered to springs with sufficiently high spring constants, 1 to eliminate the possible unwarranted artifacts of a mechanically rigid system in recovering the true slip length values from a dynamic data set. 2 The Simple Point Charge/Extended (SPC/E) model was used to define the water molecules and their interactions. 3 Interaction between the substrate atoms was accounted via the LJ potentials parametrized by σ and ε.…”

“…While new technology developments have continued to disrupt nature to bring in unwarranted environmental imbalance, nature continues to offer solutions to sustainable energy harvesting and storage. Electric eels, for example, demonstrate unique nervous systems having the capacity to synchronize their electricity-producing cells in a way that sodium ions may be driven into them by an external stimulus, resulting in a temporary discharge of electricity of hundreds of volts . Analogously, natural or engineered systems having mobile ions of a net charge may drive their separation by an external stimulus (such as pressure-driven − or evaporation-induced − fluid flow) and thus set up an electrical potential, also known as the streaming potential.…”

“…Electric eels, for example, demonstrate unique nervous systems having the capacity to synchronize their electricity-producing cells in a way that sodium ions may be driven into them by an external stimulus, resulting in a temporary discharge of electricity of hundreds of volts. 2 Analogously, natural or engineered systems having mobile ions of a net charge may drive their separation by an external stimulus (such as pressure-driven 3−10 or evaporationinduced 11−20 fluid flow) and thus set up an electrical potential, also known as the streaming potential. The resulting voltage can be tapped to induce a current in an external circuit, thereby converting hydraulic energy to electrical power.…”

Elucidation of Rapid Synchronization on Electric Discharge by Use of Model Cell Systems Mimicking Electric Organs of Electric Eel

“…[4][5][6][7] The electric organ of the electric eel (Electrophorus electricus) is composed of layered electrocytes and generates the voltage of up to 600 V or more by simultaneously discharging (firing). 4,6,[8][9][10][11][12][13][14] These electrocytes in line are covered with the insulating tubular connective tissue and are arranged in a regular pattern. Each electrocyte is placed within the insulating tube, and the membrane potentials at a caudal and head sides individually change.…”