Stretchable microsupercapacitor and device comprising same

Abstract

Disclosed in the present specification is a microsupercapacitor in which an electrode, which has increased surface area and porosity by phosphoric acid treatment of multi-walled carbon nanotube (CNT) / MnO / PEDOT:PSS in a soft matrix, is encapsulated with an electrolyte containing a zwitterionic ion gel such that high conductivity, high adhesion to an electrode and excellent mechanical properties can be provided. The microsupercapacitor according to the present disclosure can be easily used as a small and portable energy storage solution for a wearable device.

Description

Stretchable micro-supercapacitor and device including the same

[0001] This specification relates to a micro-supercapacitor and a method for manufacturing the same.

[0002] Cross-reference regarding related applications

[0003] This application claims priority to Korean Patent Application No. 10-2025-0010557 filed on January 23, 2025, the entire contents of which are incorporated by reference into this application.

[0004] Explanation of government-supported research and development

[0005] This study was conducted through the following national projects.

[0006] - Ministry: Ministry of Science and ICT, Project Management (Specialized) Agency: National Research Foundation of Korea, Research Project Name: Individual Basic Research (MSIT), Research Project Title: Flexible Materials with Modular Mechanical Properties through Control of Intermolecular Interactions, Project No.: 2022R1A2C200825613, Unique Project No.: 2710011956

[0007] The increasing demand for small, portable energy storage devices has spurred the development of stretchable, wearable, and high-performance systems. In particular, applications related to human health monitoring and environmental sensing require high-performance and mechanically robust energy storage devices. Within this framework, microsupercapacitors (MSCs), typically composed of an electrolyte, electrodes, and spacers, offer high power density, excellent cyclic stability, and rapid charging and discharging. However, there are still challenges in developing deformable MSCs with superior energy and power densities as well as enhanced stretchability, and achieving high stretchability without significantly sacrificing MSC performance is considered a key challenge for future devices.

[0008] To address these challenges, MSCs focused on flexible and robust energy storage solutions have been reported. The first utilized various structures such as kirigami patterns, serpentine structures, and wavy structures, but was limited to exhibiting only unidirectional stretchability. The second involved coating active materials onto a stretchable substrate, but this approach was insufficient to establish effective carrier transport pathways at high strain rates.

[0009] Inherently stretchable electrodes have been developed by introducing conductive fillers and active materials into a deformable polymer matrix, and these stretchable electrodes must be combined with a stretchable separator to obtain MSCs with comprehensive stretchability. In typical stretchable MSCs, two stretchable electrodes are separated by a deformable ion-rich liquid or hydrogel, which creates an electrostatic bilayer capacitance or electrochemical pseudocapacitance in the electrodes. The long-term stability of the MSC may depend on the ion gel electrolyte, which is important for maintaining ion transport. The degradation of MSC performance over time is due to inconsistent contact between the electrolyte and electrode components and a lack of interfacial adhesion; it has been reported that MSCs fabricated using silver nanowires, poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), and fluororubber exhibited approximately 100% stretchability. To increase deformability, Li et al. fabricated a PEDOT:PSS hydrogel-based MSC achieving 200% stretchability, but the specific capacitance was 44.5 mF·cm -2 It was limited to . Despite withstanding a maximum deformation of 200%, the output of the internally expandable electrode was 200 mF·cm -2 It was less than. Therefore, a new material system and synthesis method capable of simultaneously achieving high elasticity and excellent performance are required.

[0010] [Prior Art Literature]

[0011] [비특허문헌]

[0012] (비특허문헌 1) L. Li, Z. Lou, W. Han, D. Chen, K. Jiang, G. Shen, Highly stretchable micro-supercapacitor arrays with hybrid MWCNT / PANI electrodes, Adv. Mater. Technol. 2 (2017) 1600282.

[0013] (비특허문헌 2) C. Lin, Y. F. Zhang, D. Lu, A. Silva, Z. Liu, H. Y. Yang, Low-Temperature Resistant Stretchable Micro-Supercapacitor Based on 3D Printed Octet-Truss Design, Small 19 (2023) 2207634.

[0014] (비특허문헌 3) J. Yun, H. Lee, C. Song, Y. R. Jeong, J. W. Park, J. H. Lee, D. S. Kim, K. Keum, M. S. Kim, S. W. Jin, Y. H. Lee, J. W. Kim, G. Zi, J. S. Ha, A fractal-designed stretchable and transparent microsupercapacitor as a skin-attachable energy storage device, Chem. Eng. J. 387 (2020) 124076.

[0015] (비특허문헌 4) Y. Wu, M. Wu, D. Ho, H. Hu, Biaxial Stretching Array Based on High-Energy-Efficient MXene-Based Al-Ion Micro-supercapacitor Island and Editable Stretchable Bridge, ACS Appl. Mater. & Interfaces 14 (2022) 55770-55779.

[0016] (비특허문헌 5) S. Jiao, A. Zhou, M. Wu, H. Hu, Kirigami patterning of MXene / bacterial cellulose composite paper for all-solid-state stretchable micro-supercapacitor arrays, Adv. Sci. 6 (2019) 1900529

[0017] (비특허문헌 6) H. Xiao, Z. S. Wu, F. Zhou, S. Zheng, D. Sui, Y. Chen, X. Bao, Stretchable tandem micro-supercapacitors with high voltage output and exceptional mechanical robustness, Energy Storage Mater. 13 (2018) 233-240

[0018] (Non-patent Document 7) W. Tian, ​​Y. Li, J. Zhou, T. Wang, R. Zhang, J. Cao, M. Luo, N. Li, N. Zhang, H. Gong, J. Zhang, L. Xie, B. Kong, Implantable and biodegradable micro-supercapacitor based on a superassembled three-dimensional network Zn@ PPy hybrid electrode, ACS Appl. Mater. & Interfaces 13 (2021) 8285-8293.

[0019] (Non-patent Document 8) W. Yan, J. Li, G. Zhang, L. Wang, D. Ho, A synergistic self-assembled 3D PEDOT: PSS / graphene composite sponge for stretchable microsupercapacitors, J. Mater. Chem. A 8 (2020) 554-564.

[0020] (Non-patent Document 9) Z. Li, J. Song, H. Hu, C. Yuan, M. Wu, D. Ho, Rolled-up island-bridge (RIB): a new and general electrode configuration design for a wire-shaped stretchable micro-supercapacitor array, J. Mater. Chem. A 9 (2021) 2899-2911

[0021] The problem that the present disclosure aims to solve is to provide an adaptive and deformable high-performance microsupercapacitor (MSC) that exhibits high deformability without degrading performance.

[0022] In order to solve the above problem, one embodiment of the present disclosure is,

[0023] A porous flexible electrode comprising carbon nanotubes, nano-needle manganese phosphate, and poly(3,4-ethylenedioxythiophene) (PEDOT) within a matrix; and

[0024] An electrolyte comprising biionic ion gels positioned above and below the electrode to encapsulate the electrode;

[0025] Provides a micro-supercapacitor including

[0026] In addition, one embodiment of the present disclosure provides a device including a micro-supercapacitor.

[0027] A micro-supercapacitor according to one embodiment of the present disclosure can provide excellent mechanical properties along with high conductivity and high adhesion to the electrode by encapsulating an electrode, in which the surface area and porosity of multi-walled carbon nanotubes (CNT) / MnO / PEDOT:PSS are increased using a phosphoric acid treatment process within a soft matrix, with an electrolyte containing an amphoteric ion gel. Thus, the present disclosure can provide a high-performance MSC combining a porous nanocomposite electrode with an amphoteric ion gel electrolyte having high adhesion and durability, and can be easily used as a small and portable energy storage solution for wearable devices.

[0028] FIG. 1a is a schematic diagram of an experimental procedure for preparing MSC as an embodiment of the present disclosure and a molecular model of an electrode and an electrolyte.

[0029] FIG. 1b is a cross-sectional SEM image of an electrode before acid treatment (CMP) in one embodiment of the present disclosure.

[0030] FIG. 1c is a cross-sectional SEM image of an electrode after acid treatment (CMP-A) in one embodiment of the present disclosure.

[0031] FIG. 1d is a figure showing the Brunauer-Emmett-Teller absorption-desorption curves of electrodes before acid treatment (CMP) and after acid treatment (CMP-A) in one embodiment of the present disclosure, and a figure showing the calculated pore size distribution for said CMP and CMP-A (inset figure).

[0032] FIG. 2a is a cross-sectional SEM image of pure MnO powder used in the preparation of one embodiment of the present disclosure.

[0033] FIG. 2b is a cross-sectional SEM image of MPNN grown after acid treatment for 12 hours in one embodiment of the present disclosure.

[0034] FIG. 2c is a figure showing an EDS mapping image of an MPNN grown after acid treatment for 12 hours in one embodiment of the present disclosure.

[0035] FIG. 2d is a TEM image of an MPNN containing CNTs in one embodiment of the present disclosure.

[0036] FIG. 2e is a TEM image of a single MPNN without CNTs in one embodiment of the present disclosure.

[0037] FIG. 2f is a figure showing a high-resolution TEM image of an MPNN showing the grid margins of a plane in one embodiment of the present disclosure.

[0038] FIG. 2g is a figure showing the XRD patterns of MnO, CMP, MPNN, and CMP-A in one embodiment of the present disclosure.

[0039] FIG. 3a shows 10 mV·s in one embodiment of the present disclosure. -1 This figure shows the CV curves of CMNP-, CMP-, and CMP-A based MSCs measured at the scanning rate.

[0040] FIG. 3b shows various scanning rates (2.5-10 mV·s) in one embodiment of the present disclosure. -1 This is a figure showing the CV curve of a CMP-A-based MSC measured in ).

[0041] FIG. 3c is a figure showing the GCD curve of a CMP-A-based MSC measured at various current densities in one embodiment of the present disclosure.

[0042] FIG. 3d is a figure showing the CV curve of a CMP-A-based MSC prepared with PH, PHV10, and PHV20 electrolytes in one embodiment of the present disclosure.

[0043] FIG. 3e is a figure showing the GCD curve of a CMP-A-based MSC prepared with PH, PHV10, and PHV20 electrolytes in one embodiment of the present disclosure.

[0044] FIG. 3f is a figure showing a ragone plot illustrating a comparison of power and energy density between a CMP-A based MSC and another flexible MSC in one embodiment of the present disclosure.

[0045] FIG. 4a is a figure showing the tensile strain-stress curves of CMP, CMP-A, PHV20, and CMP-A-based MSC in one embodiment of the present disclosure.

[0046] FIG. 4b is a figure showing the change in electrical resistance of CMP and CMP-A as a function of strain in one embodiment of the present disclosure.

[0047] FIG. 4c is a figure showing the capacitance retention and CV curve (inset) of a CMP-A-based MSC while repeating 200% repeated stretching more than 1,000 times in one embodiment of the present disclosure.

[0048] FIG. 4d is a figure showing the results of comparing the capacitance and extensibility of a CMP-A-based MSC in an extended state in one embodiment of the present disclosure.

[0049] FIG. 4e is a figure showing the results of comparing the capacitance and extensibility of a CMP-A-based MSC when 250% repeated stretching is repeated 10,000 times in one embodiment of the present disclosure.

[0050] FIG. 4f is a figure showing the results of comparing the capacitance and extensibility of a CMP-A-based MSC under various mechanical deformations in one embodiment of the present disclosure.

[0051] FIG. 4g is a figure showing the results of a comparison of capacitance and extensibility between a CMP-A based MSC and another stretchable MSC in one embodiment of the present disclosure.

[0052] FIG. 5a is a figure showing the results of measuring the capacitance of a CMP-A-based MSC worn on an arm bent at 0°, 30°, 60°, and 90° in one embodiment of the present disclosure.

[0053] FIG. 5b is a figure showing an LED connected to an MSC charged at 0% and 250% strain in one embodiment of the present disclosure.

[0054] FIG. 5c is a picture showing a real-time setting for charging and discharging an MSC using a wireless coil in one embodiment of the present disclosure.

[0055] FIG. 5d is a schematic diagram of an MCU device in one embodiment of the present disclosure.

[0056] FIG. 5e is a picture showing a demonstration of remote operation of a thermometer and hygrometer using a smartphone via Bluetooth in one embodiment of the present disclosure.

[0057] FIG. 5f is a figure showing the charging and discharging curves of a remotely operated thermometer in one embodiment of the present disclosure.

[0058] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0059] The embodiments of the present disclosure disclosed herein are illustrative for illustrative purposes only, and the embodiments of the present disclosure may be practiced in various forms and should not be interpreted as being limited to the embodiments described herein. As the present disclosure is subject to various modifications and may take various forms, the embodiments are not intended to limit the present disclosure to a specific form and should be understood to include all modifications, equivalents, and substitutions that fall within the spirit and scope of the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "having" are intended to indicate the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and do not exclude the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0060] One embodiment of the present disclosure may provide a microsupercapacitor (MSC) comprising: a porous flexible electrode comprising carbon nanotubes, nano-needle manganese phosphate (Mn3(PO4)2) and poly(3,4-ethylenedioxythiophene) (PEDOT) in a matrix; and an electrolyte comprising an amphoteric ion gel positioned above and below the electrode to encapsulate the electrode.

[0061] In one embodiment, the porous flexible electrode comprising carbon nanotubes, nano-needle manganese phosphate (Mn3(PO4)2) and poly(3,4-ethylenedioxythiophene) (PEDOT) in the matrix may be formed by phosphoric acid treatment of a composite comprising carbon nanotubes, MnO, and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) in the matrix. One embodiment of the present disclosure may provide enhanced surface area and porosity by forming nano-needle-shaped manganese phosphate with a high aspect ratio through such phosphoric acid (H3PO4) treatment.

[0062] In the present disclosure, the nano-needle manganese phosphate is manganese phosphate formed in the form of nano-sized needles, and is used with the same meaning as manganese phosphate nano-microneedles (MPNN). In one embodiment, the diameter of the nano-needles may be an average of 1 to 150 nm. In one embodiment, the nano-needle manganese phosphate is formed by phosphoric acid treatment of MnO, specifically by immersion in H3PO4, and the inventors confirmed that the nano-needle length increases as the immersion time in H3PO4 increases.

[0063] In one embodiment, the matrix may be a flexible elastomer. For example, the flexible elastomer may include natural rubber, synthetic rubber, PDMS, Ecoflex, thermoplastic polyurethane, etc.

[0064] Additionally, in one embodiment, the amphoteric ion gel may comprise one or more selected from the group consisting of poly(N-hydroxyethylacrylamide-co-3-(1-vinyl-3-imidazolio)propanesulfonate (PHV), sulfobetaine methacrylate, sulfobetaine ethyl acrylate, sulfobetaine trimethylammonium, sulfobetaine vinylimidazole, carboxybetaine methacrylate, carboxybetaine acrylamide, carboxymethylbetaine acrylamide, carboxybetaine vinylimidazole, 2-methacryloyloxyethyl phosphorylcholine, 2-polyoxyethyl phosphorylcholine, polyphosphorylcholine methacrylate, and 1-vinyl-3-imidazoliopropanesulfonate. In one embodiment, the amphoteric ion gel may comprise one or more selected from the group consisting of poly(N-hydroxyethylacrylamide-co-3-(1-vinyl-3-imidazolio)propanesulfonate. The ionic gel may be immersed in an ionic liquid. More specifically, it may be dried after immersion in the ionic liquid. Specifically, the ionic liquid comprises one or more cations selected from the group consisting of 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-hexyl-3-methylimidazolium, N-butylpyridinium, N-hexylpyridinium, triethylmethylammonium, tributylmethylammonium, tetrabutylphosphonium, and trihexyltetradecylphosphonium, and Cl - , Br - , I - , TFSI - , FSI - , OTf - , DCA - and SCN - It may be an ionic liquid composed of one or more anions selected from the group consisting of. Specifically, the ionic liquid may be 1-ethyl-3-methylimidazolium trifluoromethanesulfonate.

[0065] In one embodiment, the PHV of the amphoteric ion gel can be prepared by radical polymerization of N-hydroxyethyl acrylamide (HEAm) and 3-(1-vinyl-3-imidazolio)propanesulfonate (VIPS). In the polymerization reaction, N,N′-methylenebis(acrylamide) (N,N′-methylenebis(acrylamide), bisAA) may be used as the crosslinking agent, and α-ketoglutaric acid (KGA) may be used as the photoinitiator. Then, the swelling medium may be replaced with 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIM][Otf]), and the residue may be heated and evaporated to obtain an ion gel. The abundant hydrogen bonding and ππ interactions between the PHV network and [EMIM][Otf] in the above-prepared ion gel impart enhanced mechanical properties, and the paired ion VIPS have the advantage of facilitating ion transfer within the electrolyte. Thus, one embodiment can provide high conductivity and strong adhesion to the electrode by using the ion gel containing the above-prepared amphoteric portion as an MSC electrolyte.

[0066] The micro-supercapacitor according to one embodiment has 292 mF·cm² through the combination of the electrode and electrolyte as described above, as confirmed in the test example described later. -2 Specific capacitance, 40.7 μWh·cm -2 The energy density of, 500.4 μW·cm² -2 Excellent performance can be achieved with a power density. In addition, the capacitance retention rate exceeds 95% even at 300% stretching, which is attributed to the inherent elasticity of the micro-supercapacitor of the present disclosure.

[0067] The present disclosure may provide a device comprising a micro-supercapacitor according to the above embodiments. For example, it can be applied to various fields such as power supplies for wearable electronic devices, portable healthcare monitoring devices, environmental sensing devices, smart clothing, and bio-attached medical devices. Furthermore, one embodiment of the present disclosure can simultaneously satisfy the high elasticity and stable electrochemical performance required for human-attached devices, and thus can be utilized as a core component of next-generation wearable devices. For example, the micro-supercapacitor can interface with a microcontroller unit to facilitate wireless charging and discharging via a smartphone and enable remote operation of a medical device.

[0068] The present disclosure will be explained in more detail below through examples. These examples are solely for the purpose of illustrating the present disclosure, and it will be obvious to those skilled in the art that the scope of the present disclosure is not to be interpreted as being limited by these examples.

[0069] [Preparation Example]

[0070] ingredient

[0071] N-hydroxyethyl acrylamide (HEAm) (97.0%), α-ketoglutaric acid (KGA) (97.0%), 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIM][Otf]) (98%), 1-vinylimidazole (≥99%), 1,3-propanesulfone (98%), CNT (inner diameter ~7 nm, 95% carbon), phosphoric acid (85 wt% in H2O), PEDOT:PSS, and manganese(II) oxide (MnO, powder, 60 mesh, 99%) were purchased from Sigma-Aldrich (St. Louis, Missouri, USA). N,N′methylenebis(acrylamide) (bisAA) (2% aqueous solution) was purchased from Bio Basic (Markham, Canada). Acetonitrile (99.8%) was purchased from Daejeong Chemical & Metal Co., Ltd. (Siheung, Korea). The flexible elastomer Ecoflex 00-30 and silicone diluent were purchased from Smooth-On (Macoon, Pennsylvania, USA). All chemicals were used as received without further purification.

[0072] Synthesis of 3-(1-vinyl-3-imidazolio)propanesulfonate (VIPS)

[0073] 1-vinylimidazole (0.22 mol, 20 mL) was added to acetonitrile (100 mL). An equimolar amount of 1,3-propanesulfone (0.22 mol, 22 mL) was added dropwise to the 1-vinylimidazole solution. To remove reaction inhibitors such as oxygen, the flask was sealed with a rubber diaphragm and bubbled with nitrogen for 25 minutes. The mixture was then stirred at 34°C for 1 day. VIPS formed as a white precipitate (yield 72%) and was washed at least 3 times with diethyl ether. Finally, the product was vacuum dried and stored at room temperature (RT) for 48 hours. The purity of VIPS was determined using 1H nuclear magnetic resonance (NMR, 400 MHz, D2O, δ): 9.02(s, 1H), 7.73(s, 1H), 7.57(s, 1H), 7.06(t, 1H), 5.73(d, 1H), 5.36(d, 1H), 4.35(t, 2H), 2.87(t, 2H), 2.28(m, 2H).

[0074] Electrode fabrication and acid treatment

[0075] The 3D printing nanocomposite ink was prepared by mixing 0.12 g of CNT, 0.10 g of MnO, and 1.0 g of PEDOT:PSS paste in 2.0 mL of Ecoflex. CMP samples with various CNT / MnO compositions but identical Ecoflex and PEDOT:PSS content were prepared to optimize mechanical and electrical properties as summarized in Table 1. The PEDOT:PSS paste was prepared by dispersing 7 wt% of PEDOT:PSS in 85% (w / w) water-soluble phosphoric acid. A diluent was added to control the viscosity of the nanocomposite ink (10 wt% relative to the total elastomer). The nanocomposite ink (indicated as CMP) containing CNT, MnO, and PEDOT:PSS in Ecoflex was printed at room temperature at a speed of 2 mm·s as shown in Fig. 1a. -1 , extrusion speed 0.32mm 3 ·s -1It was printed. After 1 hour, the 3D-printed nanocomposite CMP electrode was immersed in H3PO4 for 12 hours to complete growth and surface etching. The treated electrode was washed three times with distilled water to remove remaining H3PO4 and dried at RT for 6 hours. The acid-treated CMP nanocomposite was labeled CMP-A.

[0076] Composition of CNT and MnO for various CMP manufacturing. Sample Name Composition CNT (g) MnO (g) CMP 10.0 80 CMP 20.1 00 CMP 30.1 20 CMP 40.1 20.1 0 CMP 50.1 20.2 0 CMP 60.0 22 CMP 70.0 40.1 8 CMP 80.0 80.1 4 CMP 90.1 20.1 0 CMP 100.1 60.0 6

[0077] Manufacture of Electrolytes and Micro Supercapacitors (MSCs)

[0078] To prepare a PHV ion gel for an MSC device, a pregel solution (10 mL) containing 1.959 g of HEAm, 1.039 g of VIPS, 1.639 mg of bis-AA (0.05 mol% of total monomer), and 0.844 g of KGA (1 mol% of total monomer) was sealed with a rubber diaphragm and bubbled with nitrogen for 15 minutes. The resulting solution was immediately poured into a glass mold (76.2 mm x 25.4 mm) secured by a spacer (1 mm thick). Polymerization occurred by irradiation under a UV lamp (365 nm) for 15 minutes, forming a hydrogel layer. The hydrogel was cut in half to form the outer layer of the MSC, and the prepared CMP electrode was sandwiched therein. Subsequently, the inner edge of the MSC was bonded by injecting a small amount of the pregel solution and polymerizing it under a UV lamp for another 15 minutes. The network medium was replaced with an ionic liquid by immersing the formed hydrogel in [EMIM][Otf]. Finally, the water in the gel network was heated at 100°C for 2 hours to evaporate it, forming a PHV ionic gel that encapsulates the CMP-A electrode.

[0079]

[0080] The MSC manufactured above underwent various electrochemical tests described below, and the measurement methods and instruments used are as follows.

[0081] measurement

[0082] Stress-strain curves were obtained for an electrode (thickness: 0.5 mm, length: 1.4 cm, width: 0.1 cm), an ion gel electrolyte (thickness: 1 mm, length: 1.0 cm, width: 0.5 cm), and an MSC device (thickness: 3.7 mm, length: 2.0 cm, width: 2.5 cm) at a tensile stroke speed of 50 mm·min -1 It was recorded using a Universal Testing Machine (UTM) (EZ-SX, Shimadzu, Kyoto, Japan). Wrap shear adhesion strength tests were performed using a UTM on the electrolyte (thickness: 1 mm, length: 6.0 cm, width: 2.0 cm) and the substrate (thickness: 1 mm, length: 6.0 cm, width: 2.0 cm), at 50 mm·min in the sandwich contact area (length: 1.5 cm, width: 2.0 cm). -1Force was applied at a specific speed. The NMR spectrum of D2O was recorded using a Bruker Ascend 400 MHz spectrometer (Billerica, MA, USA). Optical transmittance was measured using an Evolution One spectrometer (Thermo Fisher Scientific, Waltham, MA, USA). Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) images of the electrodes were obtained using a Regulus 8100 (Hitachi, Tokyo, Japan). Transmission electron microscopy of the nanomaterials was performed using a TALOS F200X (Thermo Scientific, Massachusetts, United States). X-ray photoelectron spectroscopy (XPS) measurements were performed using an AXIS SUPRA instrument (Shimadzu, Kyoto, Japan). Brunauer-Emmett-Teller (BET) analysis was performed using a Quantachrome Autosorb-iQ instrument (Anton Paar GmbH, Graz, Austria) to determine the surface area and pore size. X-ray diffraction (XRD) measurements were performed using an Ultima IV diffractometer (Rigaku, Tokyo, Japan). The expansion rate was determined by calculating the change in ion gel surface area measured using an Aven Mighty Scope 5 M digital microscope (Ann Arbor, MI, USA). Fourier transform infrared spectroscopy (FTIR) spectra were measured using a Cary 630 FTIR spectrometer (Agilent, CA, USA). Ionic conductivity was measured at RT using an LCR meter 4100 series (Wayne Kerr Electronics, Bognor Regis, UK). A Zive SP1 electrochemical workstation (WonATech Co., Ltd., Seoul, South Korea) was used for electrochemical measurements of the MSC.

[0083] The various characteristics of MSC were calculated using the following mathematical formula.

[0084] [Mathematical Formula 1]

[0085]

[0086] [Mathematical Formula 2]

[0087]

[0088] [Mathematical Formula 3]

[0089]

[0090] Here, C A is the area specific capacitance, I d ε is the area current density, Δ is the discharge time, Δ is the cell potential, E A is the area energy density, P A represents area power density.

[0091]

[0092] [Test Example 1]

[0093] First, as an embodiment of the present disclosure, the following experiment was performed to analyze the characteristics of an amphoteric ion gel.

[0094] Amphoteric ion gels, namely PH, PHV10, and PHV20, were prepared according to the method of the above preparation example, but with different VIPS contents, using 0, 10, or 20 mol% VIPS. As a result, the conductivity of PHV20 (1.4 × 10⁻⁶) -2 S · cm -1 ) is poly(N-hydroxyethylacrylamide)(PH)(1.1 × 10⁻⁶ that does not contain a paired moiety -2 S · cm -1 It was higher than ). PHV20 also showed high transparency, with a transmittance exceeding 98% in the visible light wavelength range for a thickness of 1 mm.

[0095] In addition, the characteristics of the CMP and CMP-A produced in the above manufacturing example were analyzed as follows.

[0096] Scanning electron microscope (SEM) images of CMP and CMP-A in Figs. 1b and 1c, respectively, show morphological changes within the electrodes before and after acid treatment. The acid-treated electrode (CMP-A) exhibited larger pores with grown needle-shaped structures. In contrast, CMP was confirmed to have an interconnected but low-porous structure with no observable nanostructures on the surface or within the pores. Furthermore, as shown in the Brunauer-Emmett-Teller (BET) absorption-desorption curve in Fig. 1d, the specific surface area (SSA) of CMP and CMP-A was 0.809 cm², while the SSA of CMP had a pore volume of 0.809 cm³. 3 g -1 162.9 m when 2 g -1 While it was calculated as such, the SSA of CMP-A has a pore volume of 1.192 cm³ 3 g -1 When 251.2 m 2 g -1 It was calculated as follows. The pore size distribution (refer to the inset in Fig. 1d) indicates that larger mesopores were formed after acid treatment. Additionally, the SSA of the CMP-A is compared to the previously reported SSA of the stretchable MSC, which is 100 m 2 g -1 It is a significantly higher value than it was.

[0097] This means that a highly porous 3D interconnected structure, as shown in Fig. 1c, was efficiently formed by acid treatment of the CMP nanocomposite, due to the formation of manganese phosphate nano-microneedles (MPNN) and the separation of PSS and PEDOT. Chemical formula 1 below represents the reaction scheme for the formation of MPNN from MnO contained in CMP through H3PO4 treatment.

[0098] [Chemical Formula 1]

[0099] 3MnO + 2H3PO4→ Mn3(PO4)2+ 3H2O

[0100]

[0101] [Test Example 2]

[0102] The following experiment was conducted to confirm the characteristics of the manganese phosphate nano-microneedle (MPNN) formed by the phosphoric acid treatment in the above preparation example.

[0103] Figures 2a and 2b are SEM images of pure MnO powder formed after 12 hours of acid treatment and MPNN prepared in the above preparation example, respectively. Although the pure MnO powder contained irregularly shaped particles with no particular size (Figure 2a), it can be confirmed that nanoneedle growth occurred due to the acid treatment of MnO (Figure 2b). In addition, the presence of Mn, O, and P in a single MPNN was confirmed through energy dispersive X-ray spectroscopy (EDS) mapping (Figure 2c). Furthermore, the presence of C, O, Mn, and P was confirmed through the EDS spectrum of the electrode after acid treatment.

[0104] In addition, X-ray diffraction (XRD) analysis was performed to confirm the structure of MPNN. As a result, pure MnO exhibits two sharp peaks at 34.98° and 40.06°, which correspond to the (111) and (002) peaks, respectively. CMP exhibits two amorphous peaks centered at 12.08° and 23.76°, corresponding to Ecoflex and PEDOT:PSS, respectively. The peak observed at 25.42° indicates the presence of CNTs within the CMP and CMP-A matrices. In CMP-A, the PEDOT:PSS peak shifts to 24.60° and increases in intensity. This variation, characterized by the shifted and enhanced peaks, is attributed to the detachment of PSS from PEDOT facilitated by H+ doping. When PSS is detached from PEDOT, the π-π stacking interaction between the PSS benzene ring and the PEDOT thiophene ring is reduced. Consequently, this separation promotes a more highly organized PEDOT structure. The organized PEDOT structure enhances the crystallinity of the entire complex, leading to increased strength. Peaks observed at 34.98° and 40.06° confirm the presence of MnO within the pretreated sample. A total of 13 distinct peaks were identified in the XRD spectrum of MPNN, along with very small (1 1 1) and (2 0 0) MnO peaks. These MnO peaks suggest that MPNN growth originated from MnO particles. After growth was complete, some undissolved MnO particles remained. In the XRD graph of sample CMP-A after acid treatment, all peaks of MP were displayed, indicating that MPNN successfully grew within the Ecoflex / PEDOT:PSS matrix, which contributes to the formation of penetration pathways and increased porosity of the nanocomposite. All 13 peaks of MP were assigned Miller indices, and the corresponding interplanar spacings were calculated.

[0105] Table 2 below shows the XRD peak positions, corresponding d-intervals, and Miller indices for MPNN.

[0106]

[0107] The above MPNN structure was further verified using a transmission electron microscope (TEM). Figure 2d shows several MPNNs with a thickness of ~78.25 nm, which demonstrates the formation of nanoscale MPNNs as shown in Figure 2e. High-resolution TEM analysis revealed a lattice fringe with a d-spacing of 0.78 nm, which corresponds to the (102) plane (Figure 2f), which is in good agreement with the calculations from the X-ray diffraction (XRD) pattern below (Table 2). As shown in Figure 2g, the XRD pattern of pure MnO showed two sharp peaks at 34.98° and 40.06°, which correspond to the (111) and (002) planes, respectively. On the other hand, the XRD pattern of the MPNN contained 13 characteristic peaks of manganese phosphate, as shown in Table S1.

[0108] CMP and CMP-A were analyzed using X-ray photoelectron spectroscopy (XPS) to confirm the formation of manganese phosphate. Analysis of the Mn 2p, P 2p, and S 2p peaks for each CMP and CMP-A revealed that for CMP, Mn 2p3 / 2 and Mn 2p1 / 2 peaks appeared at ~12 eV, which corresponds to the spin-orbit splitting of Mn 2p occurring on the pure MnO phase of CMP. For CMP-A, the Mn 2p3 / 2 and Mn 2p1 / 2 peaks can be split into three peaks due to the presence of Mn +2, +3, and +4 oxidation states.

[0109] From the above experiments, it was confirmed that one embodiment of the present disclosure can produce a much thinner needle-shaped manganese phosphate composite using a simple acid treatment process, and the MSC of the present disclosure can improve electron transfer by providing an efficient conductive network with a large surface area through the structure.

[0110] One embodiment of the present disclosure adopts a coil-shaped structure in which PEDOT:PSS in a CMP nanocomposite is connected by Coulomb interactions with PEDOT and PSS. Negatively charged PSS - The chains hinder electron transfer, thereby limiting the conductivity of PEDOT:PSS. The second process is involved in forming a highly porous 3D interconnected structure, and due to H3PO4 treatment, H + PSS with negatively charged ions - PSSH is generated by binding to the chain. Subsequently, PSSH becomes PEDOT + It is separated from the electrons, facilitating electron transfer. The electrical resistances measured for CMP and CMP-A were 86Ω and 54Ω, respectively, indicating that conductivity was improved by acid treatment. The formation of MPNN in CMP-A may also contribute to the reduction in resistance, as demonstrated by a control sample composed of CNT / pre-synthesized MPNN / PEDOT:PSS(CMNP) showing a resistance of 78Ω.

[0111] Accordingly, XPS analysis was used to confirm the separation of PEDOT+ from PSS-. After acid treatment, the S 2p peak shifted slightly toward lower binding energies, indicating that this process promoted the separation of PEDOT and PSS as previously reported. Additionally, FT-IR analysis revealed 784 and 861 cm⁻¹ after acid treatment. -1 We confirmed that the band shifted to blue, which signifies PEDOT:PSS separation. In addition to enhancing conductivity, PEDOT:PSS separation can induce structural discontinuities in the polymer matrix because PEDOT+ is loosely associated with PSSH. These structural discontinuities in the nanocomposite are associated with the removal of PSSH from the pores, which in turn can promote the development of larger pores.

[0112]

[0113] [Test Example 3]

[0114] The electrochemical performance of an MSC using CMP-A and PHV20, prepared as an embodiment of the present disclosure in the above manufacturing example, as an electrode and an electrolyte, respectively, was confirmed in the experiment below.

[0115] First, it was investigated using cyclic voltammetry (CV) and constant current charge-discharge (GCD) analysis. As control samples, MSCs were prepared using CMP, CMNP, and PHV20. Figure 3a shows 10 mV s⁻¹ in a potential window of 0–1 V. -1 This shows the CV curves of CMNP, CMP, and CMP-A based MSCs measured at a scan rate. The integrated area within the current-potential curves of the MSCs with CMP and CMNP electrodes is 0.0014 and 0.0017 mA s cm⁻¹, respectively. -2 On the other hand, the integrated area of ​​the CMP-A-based MSC was significantly larger (0.0052 mA s cm⁻¹). -2 This result indicates that the electrochemical charge storage capacity of the CMP-A electrode is significantly larger than that of the CMP and CMNP electrodes because the conductivity and porosity generated by acid treatment have increased.

[0116] Fig. 3b is 2.5–10 mV s -1 The CV curves of the MSC with the CMP-A electrode measured at the scan rate are shown. As the scan rate increases, the integrated area of ​​the current-potential curve increases, indicating faster ion transport rates and stronger energy storage capacity. Additionally, due to the hybrid active material of the CMP-A-based MSC, the CV curve exhibits a quasi-rectangular shape without large redox peaks, suggesting that energy storage is dominated by capacitive behavior. Using the Dunn method, positive and negative b values ​​of 0.87 and 0.86, respectively, were calculated from the capacity curve as a function of scan rate, suggesting that charge storage is primarily governed by capacitive phenomena rather than diffusion.

[0117] Furthermore, the electrochemical performance of the CMP-A-based MSC was verified through GCD analysis performed between 0 and 1 V at various current densities. As shown in Fig. 3c, the GCD profile deviated from the characteristic triangular shape of symmetric EDLCs, which may be due to the involvement of charge transfer reactions similar to the behavior observed in batteries. This phenomenon confirms that both capacitor and battery mechanisms are involved in the charge storage dynamics of the hybrid supercapacitor. Using GCD analysis and Equation 1 above, values ​​of 0.25, 0.30, 0.35, and 0.40 mA cm⁻¹, respectively -2 At current densities of 292.8, 255, 234, and 216 mF cm⁻¹ -2 The specific capacitance value was calculated. As a result, the capacitance gradually decreased as the current density increased. This excellent performance is attributed to the high porosity and surface area of ​​CMP-A, as revealed by SEM and BET analyses. Furthermore, electrochemical impedance spectroscopic analysis of the CMP-A-based MSC showed a low charge transfer resistance value of 72Ω.

[0118]

[0119] [Test Example 4]

[0120] As an example, CMP samples were prepared with different CNT / MnO compositions but identical Ecoflex and PEDOT:PSS contents to optimize mechanical properties such as stretchability and electrical properties such as resistance. Next, the contribution of the PHV electrolyte to the high performance of the developed MSC was investigated using CV and GCD measurements. For these tests, MSCs were fabricated using CMP-A as the electrode and PHV electrolytes containing varying amounts of VIPS (0–20 mol%).

[0121] Fig. 3d shows 10mV s at a potential window of 0–1V. -1This shows the CV profiles of MSCs with PH, PHV10, and PHV20 electrolytes measured at the scan rate. The integrated area of ​​the CV profile of the MSC with PHV20 was twice that of the MSC with PH, indicating that the binary ion portion improves charge transport efficiency and generates high capacitance. As can be seen in Fig. 3e, the charge and discharge times increased with increasing VIPS content in the electrolyte. The MSC with PHV20 showed 292 mF cm⁻¹. -2 It exhibited capacitances of , which correspond to MSCs with PH and PHV10 (138 and 249 mF cm⁻¹, respectively). -2 It exceeds the capacitance of ). The excellent performance of this MSC is attributed to the high conductivity and outstanding adhesion of the PHV20 electrolyte. The conductivity of PHV20 is 1.4 × 10⁻⁶ -2 S cm -1 On the other hand, the conductivity of pH is 1.1 × 10 -2 S cm -1 VIPS both ions can promote high ion separation in ionic liquids and form ion transport pathways to enhance ion transport. In addition, the PHV electrolyte exhibits strong adhesion properties, indicating that good contact can be achieved between the electrolyte and the CMP-A electrode.

[0122] To quantify the adhesion strength, lab shear tests were performed on PH, PHV, and PHV20 using CMP-A. As a result, adhesion strengths of 6.93, 10.47, and 13.60 kPa were obtained for PH, PHV10, and PHV20, respectively. The increase in adhesion strength was proportional to the amphoteric VIPS content of the electrolyte, as increasing the VIP content resulted in a greater number of imidazole N+ groups capable of interacting with CMP.

[0123] The Ragone plot presented in Fig. 3f shows the performance of the optimized developed MSC fabricated with CMP-A and PHV20. This device demonstrates superior performance compared to recently reported stretchable MSCs, with an impressive energy density of 40.7 μWh cm⁻¹. -2 (Calculated using Equation 2) and power density 500.4 μW cm⁻¹ -2 (Calculated using Equation 3) is shown. From this, it can be confirmed that the CMP-A based MSC according to the present disclosure not only has superior performance compared to other devices but also achieves a balanced combination of energy density and power density.

[0124]

[0125] [Test Example 5]

[0126] The high mechanical and electrical properties of the MSC according to one embodiment of the present disclosure, prepared in the above manufacturing example, were analyzed.

[0127] Figure 4a shows the tensile strain-stress curves of the CMP, CMP-A, PHV, and the assembled CMP-A-based MSC device. The CMP and CMP-A can elongate up to 305% and 280%, respectively, at fracture stresses of 170 kPa and 150 kPa. This result indicates that acid treatment did not significantly alter the mechanical properties of the electrodes. The PHV and MSC exhibited elongations of up to 561% and 551%, respectively, at fracture stresses of 112 kPa and 130 kPa. The MSC exhibited mechanical properties similar to those of the PHV, which acts as a shell. The solvent-affinity imidazole moiety of the PHV absorbed more of the imidazole-based ionic liquid [EMIM][Otf], allowing for a higher expansion ratio. Consequently, the modulus of the PHV network was lower than that of the PHV, which does not contain the paired ionic VIPS moiety.

[0128] For an MSC to operate optimally, the electrical resistance of the electrodes must be low, which enables the generation of greater energy and power density. Reduced electrode resistance mitigates energy loss as heat during charge-discharge cycles, thereby improving the efficiency of the energy conversion process. Therefore, in addition to mechanical rigidity, achieving low electrode resistance even in a stretched state is crucial for developing highly flexible, high-performance MSCs.

[0129] Figure 4b confirms the change in relative resistance with strain for the CMP and CMP-A electrodes. The change in relative resistance with elongation for CMP (R / R0 = 2.67 at 250% strain) was greater than that of CMP-A (R / R0 = 1.64 at 250% strain). The electrical stability of the electrodes in the strained state depends on the permeation network between entangled CNTs, PEDOT:PSS, and manganese phosphate dispersed in Ecoflex. The growth of high aspect ratio MPNNs in CMP-A enables the maintenance of an efficient permeation network even at high strains. The high aspect ratio of MPNNs supports network continuity during strain, maintaining connectivity with PEDOT and CNTs during deformation. The formation of PEDOT+ through acid treatment may also minimize the increase in resistance during elongation. PEDOT+ can electrostatically bind to CNTs due to the surrounding ππ cloud on the CNT surface, providing a more efficient pathway for electron transfer. Therefore, the combination of PEDOT+ and CNT and the growth of MPNN synergistically enhanced electrical conductivity during elongation.

[0130] In addition, to verify the structural integrity and long-term stability of the CMP-A-based MSC, more than 1,000 cycles of cyclic stretching tests were performed at 200% strain. As a result, as shown in FIG. 4c, it was confirmed that the change in electrical resistance of the MSC is fully repeatable and reproducible without significant change. This indicates that the MSC according to one embodiment of the present disclosure possesses high mechanical and electrical properties.

[0131]

[0132] [Test Example 6]

[0133] Based on the excellent mechanical and electrical properties of the MSC according to one embodiment of the present disclosure confirmed in the experiments above, the device performance was tested under high strain. First, the CMP-A based MSC was placed in a motorized stretching stage, and CV curves were recorded at various stretching rates up to 300% (Fig. 4d). As can be seen from the capacitance retention profile calculated from the CV curves (inset, Fig. 4d), the stretched MSC achieved a capacitance retention rate of 95.0% at 300% elongation compared to the initial state, demonstrating excellent charge storage performance in the stretched state. Furthermore, the CMP-A based MSC showed an excellent capacitance retention rate of 95.3% even after 10,000 cycles at 250% elongation (Fig. 4e).

[0134] Next, the CV curves of the CMP-A-based MSC were recorded under various deformations such as bending, rolling, and torsion (Fig. 4f). Even when the device was twisted, it achieved a capacitance retention rate of 98.0%, demonstrating the excellent stability of the CMP-A-based MSC against extreme mechanical deformation.

[0135] FIG. 4g compares the specific capacitance and stretchability of the MSC with other previously reported MSCs. In particular, 300% elasticity and 292.8 mF cm -2A CMP-A based MSC having a specific capacitance showed superior performance compared to recently reported systems. [5, 6, 7, 8, 9, 18, 48, 50, 53] used as comparative examples in FIG. 4g each refer to non-patent literatures 1 to 9 described above as prior art of the present disclosure. Each of the previously reported devices achieved capacitance retention rates of 96.8%, 87.1%, 71.8%, 97.6%, and 76.4% at 100%, 50%, 100%, 50%, and 30% extensions, respectively. Most of the previous systems maintained less than half of the initial non-capacitance in the extended state (100% extension) and were lower than the performance benchmark set by the CMP-A based MSC according to the present disclosure, which showed a capacitance retention rate of 95.3% after 10,000 cycles in a 250% extension.

[0136] The performance of the MSC developed for the realization of a suitable wearable power source was demonstrated by wearing it on the arm. As shown in the photograph in Fig. 5a, the CMP-A based MSC was attached to the bent part of the arm using medical tape, and the capacitance was measured when the arm was bent. As a result, the MSC maintained a capacitance retention rate of 98.5% within the arm bending angle range (0°-90°, Fig. 5a). In addition, the light-emitting diode (LED) connected to the MSC emitted light as the charged MSC supplied electricity during arm bending, indicating the excellent performance of the MSC during bending.

[0137] The performance of the MSC was also tested in a deformed state due to dynamic stretching. As can be seen in Fig. 5b, the charged MSC was installed on a motorized stage that continuously stretches the device and connected to an LED bulb. The LED bulb emitted a high constant brightness during continuous stretching of 250%, confirming the stable performance of the MSC during dynamic movement.

[0138] Next, wireless charging and discharging of the MSC were demonstrated using a wireless charging coil (Fig. 5c). When the two coils were brought close together, an alternating electromagnetic field was generated, inductively transferring energy to another coil placed in parallel. Wireless charging to 2V was achieved within 168 seconds. The discharge time of the charged MSC exceeded 3.5 minutes, confirming its excellent charge storage capabilities.

[0139] As a further experiment, the charging and discharging of the aforementioned MSCs were controlled using a smartphone coupled with an ATmega328P 16MHz chip-based microcontroller (MCU) device (an Arduino Uno R3 with an HC-06 Bluetooth module). Fig. 5d shows a schematic diagram of the MCU-driven charging / discharging setup for operating electronic devices within a range of 10–15 meters. A Bluetooth application was developed using MIT App Inventor to operate the MCU device. Two MSCs connected in series were powered by the output of the MCU, which had a ground connection. As a result, as shown in Fig. 5d, the thermometer and hygrometer operated well using electrical energy supplied from the charged MSCs. The charging process of the MSC connected to the thermometer and the subsequent discharging process are shown in Fig. 5e. The discharge time was over 150 seconds, demonstrating the practical utility of this remote control system.

[0140] Through the experiments described above, it was confirmed that the electrode of the MSC according to one embodiment of the present disclosure can provide enhanced conductivity and porosity by mixing CNT, MnO, and PEDOT:PSS with Ecoflex and then treating with phosphoric acid to form MPNN and remove PSSH. In addition, as one embodiment, the electrolyte encapsulating the electrode incorporates a paired ion gel with high conductivity and adhesion, so that the MSC has a conductivity of 292.8 mF cm⁻¹. -2 capacitance, 40.7 μWh cm -2 The energy density of, 500.4 μW cm⁻¹ -2The power density was demonstrated. Thanks to the flexible components and high aspect ratio MPNN, the MSC of the present disclosure exhibited an intrinsic stretchability of 300%. An excellent capacitance retention rate of over 95% was achieved at 300% stretch, and a capacitance retention rate of 95.3% was maintained even after 10,000 cycles of 250% stretch, confirming the excellent performance of the CMP-A-based MSC under various deformations including bending and twisting. Furthermore, it was confirmed that a device including the MSC of the present disclosure demonstrates an electrical energy solution suitable for numerous wearable devices by powering LEDs, thermometers, and hygrometers through wireless charging and discharging via a smartphone.

Claims

1. A porous flexible electrode comprising carbon nanotubes, nano-needle manganese phosphate, and poly(3,4-ethylenedioxythiophene) (PEDOT) within a matrix; and An electrolyte comprising biionic ion gels positioned above and below the electrode to encapsulate the electrode; A microsupercapacitor (MSC) including 2. A micro-supercapacitor according to claim 1, wherein the porous flexible electrode is formed by phosphoricing a composite comprising carbon nanotubes, MnO, and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) in the matrix.

3. A micro-supercapacitor according to claim 1, wherein the two ionic gels comprise one or more selected from the group consisting of poly(N-hydroxyethylacrylamide-co-3-(1-vinyl-3-imidazolio)propanesulfonate), sulfobetaine methacrylate, sulfobetaine ethyl acrylate, sulfobetaine trimethylammonium, sulfobetaine vinylimidazole, carboxybetaine methacrylate, carboxybetaine acrylamide, carboxymethylbetaine acrylamide, carboxybetaine vinylimidazole, 2-methacryloyloxyethylphosphorylcholine, 2-polyoxyethylphosphorylcholine, polyphosphorylcholine methacrylate, and 1-vinyl-3-imidazoliopropanesulfonate.

4. A micro-supercapacitor according to claim 1, wherein both ionic gels are immersed in an ionic liquid.

5. In paragraph 4, the ionic liquid comprises one or more cations selected from the group consisting of 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-hexyl-3-methylimidazolium, N-butylpyridinium, N-hexylpyridinium, triethylmethylammonium, tributylmethylammonium, tetrabutylphosphonium, and trihexyltetradecylphosphonium, and Cl - , Br - , I - , TFSI - , FSI - , OTf - , DCA - and SCN - A micro-supercapacitor comprising a combination of one or more anions selected from the group consisting of 6. A micro-supercapacitor according to claim 1, wherein the matrix is ​​a soft elastomer.

7. A device comprising a microsupercapacitor according to any one of paragraphs 1 through 6.

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