Textile-based supercapacitors for flexible and wearable electronic applications

Abstract

Electronic textiles have garnered significant attention as smart technology for next-generation wearable electronic devices. The existing power sources lack compatibility with wearable devices due to their limited flexibility, high cost, and environment unfriendliness. In this work, we demonstrate bamboo fabric as a sustainable substrate for developing supercapacitor devices which can easily integrate to wearable electronics. The work demonstrates a replicable printing process wherein different metal oxide inks are directly printed over bamboo fabric substrates. The MnO 2-nico 2 o 4 is used as a positive electrode, rGO as a negative electrode, and LiCl/PVA gel as a solid-state electrolyte over the bamboo fabrics for the development of battery-supercapacitor hybrid device. The textile-based MnO 2-nico 2 o 4 //rGO asymmetric supercapacitor displays excellent electrochemical performance with an overall high areal capacitance of 2.12 F/cm 2 (1,766 F/g) at a current density of 2 mA/cm 2 , the excellent energy density of 37.8 mW/cm 3 , a maximum power density of 2,678.4 mW/ cm 3 and good cycle life. Notably, the supercapacitor maintains its electrochemical performance under different mechanical deformation conditions, demonstrating its excellent flexibility and high mechanical strength. The proposed strategy is beneficial for the development of sustainable electronic textiles for wearable electronic applications. Smart electronic textiles have recently gained a lot of attention as a viable solution for the upcoming wearable electronics era 1,2. The electronic textiles/ garments have demonstrated enormous potential in various applications such as; healthcare monitoring devices, environmental monitoring devices, military applications, entertainment, fashion technology etc 2-4. Recently, the development of different textile-based electronic devices (like; wearable displays, wearable sensors, memory devices, and wearable transistors) have received greater attention from the scientific and engineering community, and their development is carried out on a rapid pace 4-6. However, one of the major challenges for commercialization and further growth of wearable electronics is the lack of a compatible power supply that may possess the same level of flexibility, durability, weight, biocompatibility, and strength as the device itself 7,8. The conventional energy storage devices fail to address these needs due to their rigid and bulky nature and also their inability to mount/perform on moving surfaces as is a critical need of wearable devices mounted on human and other beings 1,9-11. Therefore, there exists a strong need for the development of flexible and high-performance energy storage devices which can be easily integrated with wearable electronics. Among the various energy storage devices, thin and flexible supercapacitors are gaining more consideration for wearable electronics due to their salient features, such as excellent lifetime, lightweight, high power density, and their ability to deliver under mechanical deformation co...

Metal Coated Fabric Based Asymmetric Supercapacitor for Wearable Applications

“…The ASCs generally use carbon-based material such as graphene, carbon nanotube (CNT), graphite and their composites for negative electrode and the pseudocapacitive materials such as transition metal oxides and their composites as positive electrode [3,[21][22][23][24][25]. Some ASCs using on carbon and metal coated cloth have been reported too [18,26]. The high porosity of cloths is advantageous in terms of absorbance of aqueous active electrode ink and for converting the non-conductive cloth into conductive.…”

Recent Development of Flexible and Stretchable Supercapacitors Using Transition Metal Compounds as Electrode Materials

“…Some substrates can withstand large tensile strength, such as CNT film (52 MPa), [ 87 ] 3D‐printed ceramic lattice (30 MPa), [ 88 ] oxidized CNT fiber (67 MPa), [ 58 ] polyaniline (PANI)/bacterial cellulose (107 MPa), [ 89 ] CNT yarn (150 MPa), clay/polyvinyl alcohol (PVA)/poly(3,4‐ethylenedioxythiophene):​poly(styrene sulfonate) (PEDOT:PSS) (62 MPa), [ 90 ] CNT/graphene fiber with (≈630 MPa), [ 91 ] graphene/aramid nanofiber (101 MPa), [ 92 ] and printed reduced graphene oxide (rGO) fabric (442 MPa). [ 93 ] However, many previous reports calculated the specific capacitance merely based on the mass loading of electroactive materials without considering the weight of the substrate or current collector, which cannot accurately reflect the performance of the whole device. Furthermore, bending and stretching tests are frequently used methods to evaluate the reliability of flexible and stretchable SCs, respectively.…”

Fabric based printed-distributed battery for wearable e-textiles: a review

“…On the other hand, supercapacitors have high power density; but, the problems of low energy density and high selfdischarging rate of supercapacitor still requires solution and hence limits the practical application of smart textile electronics. Knowing that energy density is directly related to the working potential and capacitance of supercapacitor [104], the hybrid energy system combining the two energy storage devices, given in Figure 9, was also studied [105]. This concept of hybridizing battery and supercapacitor in a single electrode would help to improve thermodynamics and kinetics of an electrochemical reaction within a single device.…”