Superelastic Supercapacitors with High Performances during Stretching

Abstract

A fiber-shaped supercapacitor that can be stretched over 400% is developed by using two aligned carbon nanotube/polyaniline composite sheets as electrodes. A high specific capacitance of approximately 79.4 F g(-1) is well maintained after stretching at a strain of 300% for 5000 cycles or 100.8 F g(-1) after bending for 5000 cycles at a current density of 1 A g(-1). In particular, the high specific capacitance is maintained by 95.8% at a stretching speed as high as 30 mm s(-1).

Elastomeric and Dynamic MnO2/CNT Core–Shell Structure Coiled Yarn Supercapacitor

“…This stretchable electrode's mechanical reversibility has not been reported among other stretchable FBSs. [19][20][21][22][23][24] In addition, the constant slopes of the loading curves exhibit high modulus from 290 ( = 20%) to 325 MPa ( = 40%), while hysteretic energy dissipations by the recovery friction force were observed during unloading. 29 The capacitance retention of the coiled supercapacitor under mechanically static strain (2% s -1 ) is characterized by comparing its CV curves before and after 37.5% strain was applied, as shown in Figure 4C.…”

Toward Soft Skin‐Like Wearable and Implantable Energy Devices

“…Reproduced with permission. [46] Copyright 2015, Wiley-VCH. d) Photograph of the transparent stretchable AuNWs supercapacitor.…”

“…This is because reversible oxidation/reduction reaction(s) will occur at the electrode/ electrolyte interface of the pseudocapacitor, giving 10-100 times more capacitance than that of pure carbon-based EDLC. [61] To date, various novel materials with intrinsic stretchability (e.g., carbon nanotubes, carbon nanofibers, graphene, and metal nanowires) [18,45,46,51] and structural designs (e.g., wire configuration, [62] film configuration, [12] and textile configuration) [37] have been proposed for the purpose of developing stretchable and implantable supercapacitors. We will discuss several viable configurations.…”

“…Such aligned CNT sheet could also be wrapped onto elastomeric fibres with a pre-strain of only 100%, to achieve superior stretchability of over 400% (Figure 6a). [46] The resistance changes upon stretching are highly dependent on the helical angle between the aligned CNT sheet along the axial direction of the fibre (Figure 6b,c). Optimized stretchability is achieved with a helical angle of 80˚, where the resistance variances are within 70% at strains of ≈400%.…”

Conducting‐Polymer‐Based Materials for Electrochemical Energy Conversion and Storage

“…[53] Conducting polymers have great potential as electrode materials for supercapacitors because of high conductivity, good reversibility, high capacity, large voltage window, low environmental impact, and low cost. [54][55][56][57][58] Nevertheless, repeated swelling/shrinking during charging/discharging process is apt to cause their structural change, leading to unsatisfactory cyclic stability. [59][60][61] Up to now, three effective strategies have been explored to improve their electrochemical performance and cyclic stability: i) nanostructuring, ii) hybridization with carbon nanomaterials, and iii) hybridization with pseudo-capacitive transition metal oxides.…”