Integration of supercapacitors with enzymatic biobatteries toward more effective pulse-powered use in small-scale energy harvesting devices

Abstract

Effective integration of electrochemical devices consisting of enzyme-based biobatteries together with high power double-layer type capacitors is discussed here. An ultimate goal is to overcome a typical drawback of enzymatic power sources (biofuel cells and biobatteries): although their energy is potentially high enough to fulfill the needs of small electronic devices, their power is often too low. It is demonstrated that properly selected capacitor can support operation of such a low power device simply by supplying appropriate power pulses with fast dynamic response that is required for many applications involving fluctuating loads. Our model integrated system is obtained by coupling a series of double-layer capacitors with wellbehaved zinc/oxygen biobattery. The biobattery utilizes a stable cathodic material composed of covalently phenylated single-walled carbon nanotubes and the oxygen reduction enzyme, laccase, together with the hopeite-covered zinc rod acting as the anode. The enzymatic power source was characterized by the maximum power density of 1.8 mW cm -2 , the open circuit voltage of 1.6 V. Nevertheless, under the 50 X loading, the voltage of biobattery (electrode surface areas of ca. 0.3 cm 2 ) drops to 0 V after 2 s. The practical performance (power stability) of a biobattery has significantly improved by its parallel connection to electrochemical capacitor. The importance of such capacitor's parameters as low resistance (not more than a few hundred of milliohms), proper capacitance, and leakage current (not higher than a few microamperes) is emphasized here. The potential utility of the optimized biobattery/supercapacitor system is discussed in terms of use as a source of power to operate a digital watch.

Recent Progress on the Development of Biofuel Cells for Self‐Powered Electrochemical Biosensing and Logic Biosensing: A Review

“…Besides the novel approaches for BFCs‐based self‐powered biosensors design as mentioned above, several new trends for their development are still attractive and important: (1) Though more than fifty years has passed since the first enzymatic BFCs was reported in 1964, the power output for most enzymatic BFCs is still unsatisfied, which may lead to the relatively low sensitivity for enzymatic BFCs‐based self‐powered electrochemical biosensors and logic biosensors. In order to solve the problem, the introduction of capacitor into the external circuit of BFC is a popular choice 35, 38, 40, 41, 54, 55, 81–83. The generated electrical energy was firstly collected by the capacitor, and then the stored electrical energy was released instantaneously through a low‐cost, portable, and simple digital multimeter to obtain an amplified current.…”

“…Although considerable progress has been made in the development of BFCs‐based self‐powered electrochemical biosensors and logic biosensors, many challenges and exciting opportunities still remain in such field. For example, the sensitivity of the enzymatic BFCs‐based self‐powered electrochemical biosensors and logic biosensors was able to be increased with the assistance of capacitor 35, 38, 40, 41, 54, 55, 81–83, the power efficiency of the BFCs will be still a problem limiting their future development and real application. Most reported self‐powered electrochemical biosensors and logic biosensors based on BFCs are still in proof‐of‐concept state and they are still commonly tested in the samples that are irrelevant for real or in vivo biomedical applications.…”

Laccase-Catalyzed Reduction of Oxygen at Electrodes Modified by Carbon Nanotubes with Adsorbed Promazine or Acetosyringone

“…More and more often, biofuel cells are used as alternative energy sources, supplying devices that require a small power consumption for their work [1][2][3][4][5][6]. Biofuel cells are currently considered to be one of the most promising future energy sources and self-integrated bioelectrochemical devices [7][8][9].…”

Nanostructuring carbon supports for optimal electrode performance in biofuel cells and hybrid fuel cells

“…In addition, carbon nanotubes at the carbon electrode form a nanocomposite electrode showing supercapacitor properties. Such combination of enzymatic catalysis with charge storing matrix would improve the performance of the electrodes and provide more efficient powering abilities in a biofuel cell arrangement [36][37][38][39][40].…”