Review—Wearable Biofuel Cells: Past, Present and Future

Abstract

The perspective article provides a detailed description of the major developments in the field of wearable biofuel cells. The article expounds several attributes of this newly emerging technology and its potential to address the energy needs of wearable devices. In addition to discussing important milestones reached in this field, the article also highlights the grand challenges that are presently hindering further development of wearable biofuel cells. Particular emphasis has been devoted to major issues related to biofuel cell stability, need for generating stable, high levels of power, mechanical compliance and resiliency and device aesthetics. In addition to this, the article also offers multiple pathways to address these issues. The article aims at generating interest among researchers with diverse expertise to come together on a common platform to overcome the major challenges faced by the field of wearable biofuel cells. Such collaborative efforts will be essential for the success of wearable biofuel cells and to harness their full potential. Why Biofuel Cells for Wearable Applications?Recent development of bio-integrated wearable electronics that provide continuous information, 1,2 entertainment, 3,4 help in carrying out routine activities 5 are a result of our insatiable desire to develop technologies that make lives easy. The nascent field of body-bound electronics is still is in its infancy and there exists several challenges that ought to be addressed for successful adaptation of the technology by various market segments. [6][7][8][9] Identifying suitable wearable energy sources is one of the biggest omnipresent challenge that cuts across almost all wearable electronics fields. 10 The situation is getting further exacerbated as the field of wearable electronics advances toward developing tiny, yet complex, multi-tasking wearable devices that continuously require high levels of energy supply for optimal performance. Research efforts to overcome this issue can be broadly classified into developing low-energy electronics, 11 adaptive algorithms for intelligent, low-power consuming electronics 12 and high energy density power sources. 13 Of these, development of efficient power sources has attained the greatest attention. Usage of conventional power sources, such as, lithium ion and alkaline batteries result in increased bulkiness and rigidity of the wearable electronics wherein just a fraction of the device weight is due to electronics while the rest is because of the battery. Such integration of conventional power sources with wearable electronics thus vitiates the overall attractiveness of the wearable system. Hence, there has been a genuine effort within the scientific community toward developing new formats of power sources for wearable applications. One of the most obvious and widely explored avenues is the development of thin, flexible and even stretchable batteries and supercapacitors that can be easily mated with the human body.14-16 Such body-compliant energy storage systems are quite attracti...

Preface—JES Focus Issue on Biological Fuel Cells

“…[24][25][26][27][28] However, with the increasing popularity of wearable electronics, there has been an increased interest in wearable biofuel cells, 29 including patches and contact lenses, which are discussed in this focus issue. From a fundamental electrochemistry perspective, this issue includes papers discussing up-and-coming cofactors, 30 new enzymes, 31 and new cascades of enzymes for deep oxidation.…”

Flexible and transparent biological electric power sources based on nanostructured electrodes

“…Researchers are moving forward to develop low-energy/low-power consuming electronics and high energy density power sources (Bandodkar, 2017;Dong et al, 2016). For instance, wearable electrochemical devices combine low-power requirements, feasibility of miniaturisation, simplicity, and low production costs .…”

“…Thin, flexible and stretchable devices containing biosensors or biological power sources have been developed ( Figure 17) and they count on several advantages when it comes to biodegradability and biocompatibility when compared with conventional batteries or fuel cells (Bandodkar, 2017).…”

“…Among the bioelectronics that are being designed and developed, wearable devices seem to be a convenient alternative, since they can be worn by the user with minimal invasion and no requirement of expertise skills (Bandodkar, 2017;Falk et al, 2012a;Katz et al, 2015;Willner and Katz, 2006).…”

“…wearable electronics (Bandodkar andWang, 2014, 2016; and biosolar cells (Somasundaran et al, 2011), the transparency of the EFC should be taken into account. The use of transparent conductive nanomaterials allows improving the aesthetic and cosmetic issues that are relevant in the case of smart electronic contact lenses ) and body-attachable wearable electronic platforms Trung et al, 2016).…”