結構型超級電容器(Structural Supercapacitor, SSC)是一種兼具承載與儲能功能之多功能材料系統，可望應用於輕量化運輸工具及先進工程結構中。本研究以雙向編織碳纖維作為電極、雙向編織玻璃纖維作為介電層，搭配PVA-KOH鹼性聚合物電解液，並以環氧樹脂基材透過真空輔助樹脂轉注成型(VARTM)製備尺寸為10 × 20 cm2、樹脂含量15 wt% 之SSC。為探討尺寸效應對SSC電化學性能之影響，自母電容器裁切製備寬度固定為3 cm、長度為3 - 20 cm之五種尺寸試片，並透過多批次製造以確保結果之統計可靠性。實驗結果顯示，隨著電容器長度增加，其比電容逐漸下降，由3增加至20 cm時，比電容相對衰減達49%。此外，兩塊10 cm SSC 並聯後之比電容與單塊20 cm SSC 相比差異僅約1.6%，顯示在相同材料與製程條件下，並聯配置可有效模擬較大尺寸SSC之電化學行為。因此，本研究進一步利用並聯方式建立40與60 cm SSC，結果顯示長度由3 cm增加至60 cm時，比電容累積衰減可達93.2%，凸顯尺寸放大對性能之顯著影響。除尺寸效應外，本研究亦探討不同集電體設計對性能之影響，採用L-shaped與Busbar and 4 fingers兩種銅箔幾何形狀進行比較，以作為未來大型SSC電流收集與結構設計之參考。此外，亦初步評估再生碳纖維紙與再生碳纖維無紡布作為SSC電極材料之可行性，探討其在不同製程條件下之電化學表現，作為永續結構型儲能元件開發之基礎。本研究成功量化SSC尺寸效應對電化學性能之影響，建立尺寸與比電容間之定量關係，並驗證並聯設計於大型化評估之可行性。研究成果可作為未來SSC尺寸放大、電流收集設計及永續材料應用的重要參考，促進結構型儲能元件之發展與實際應用。

Structural supercapacitors (SSCs) are multifunctional systems that combine load-bearing capability with energy storage, offering potential for lightweight transportation and advanced structures. In this study, SSCs were fabricated using bidirectional woven carbon-fiber electrodes, a bidirectional woven glass-fiber dielectric layer, and a PVA–KOH alkaline polymer electrolyte. Vacuum-assisted resin transfer molding was used to produce a 10 × 20 cm2 master panel with a resin content of 15 wt%. Specimens 3 cm wide and 3–20 cm long were extracted from multiple batches to evaluate geometric scale effects. The specific capacitance decreased with increasing length, showing a 49% reduction from 3 to 20 cm. Two parallel-connected 10 cm SSCs differed from a single 20 cm SSC by only 1.6%, validating parallel connection as a method for simulating larger devices. This approach was further applied to equivalent lengths of 40 and 60 cm, with the 60 cm configuration showing a specific-capacitance reduction of up to 93.2% relative to the 3 cm specimen. Two copper-foil current-collector geometries, L-shaped and busbar with four fingers, were also compared to assess their influence on current collection. In addition, recycled carbon-fiber paper and nonwoven mats were preliminarily evaluated as sustainable electrode materials under different processing conditions. Overall, this study successfully quantifies the scale effects on SSC performance and validates parallel connection for large-scale evaluation. These findings provide foundational guidance for SSC scale-up, current-collector optimization, and the application of sustainable materials in future structural energy-storage systems.

[1] J. Zhang, J. Yan, Y. Zhao, Q. Zhou, Y. Ma, Y. Zi, A. Zhou, S. Lin, L. Liao, and X. Hu, "High-strength and machinable load-bearing integrated electrochemical capacitors based on polymeric solid electrolyte," Nature Communications, vol. 14, no. 1, p. 64, 2023.
[2] H. R. Khan and A. L. Ahmad, "Supercapacitors: Overcoming current limitations and charting the course for next-generation energy storage," Journal of Industrial and Engineering Chemistry, vol. 141, pp. 46-66, 2025.
[3] A. G. Pandolfo and A. F. Hollenkamp, "Carbon properties and their role in supercapacitors," Journal of power sources, vol. 157, no. 1, pp. 11-27, 2006.
[4] F. Mashkoor, M. Shoeb, B.-J. Kim, D. Kim, and C. Jeong, "Beyond Materials: The Interface as a Design Paradigm in Structural Supercapacitors," Langmuir, vol. 41, no. 41, pp. 27631-27650, 2025.
[5] C. Lei, F. Markoulidis, Z. Ashitaka, and C. Lekakou, "Reduction of porous carbon/Al contact resistance for an electric double-layer capacitor (EDLC)," Electrochimica acta, vol. 92, pp. 183-187, 2013.
[6] R. Ahmad, U. A. Khan, N. Iqbal, and T. Noor, "Zeolitic imidazolate framework (ZIF)-derived porous carbon materials for supercapacitors: an overview," RSC advances, vol. 10, no. 71, pp. 43733-43750, 2020.
[7] M. Czagany, S. Hompoth, A. K. Keshri, N. Pandit, I. Galambos, Z. Gacsi, and P. Baumli, "Supercapacitors: An efficient way for energy storage application," Materials, vol. 17, no. 3, p. 702, 2024.
[8] S. Sharma and P. Chand, "Supercapacitor and electrochemical techniques: A brief review," Results in Chemistry, vol. 5, p. 100885, 2023.
[9] J. M. Lim, Y. S. Jang, H. V. T. Nguyen, J. S. Kim, Y. Yoon, B. J. Park, D. H. Seo, K.-K. Lee, Z. Han, and K. K. Ostrikov, "Advances in high-voltage supercapacitors for energy storage systems: materials and electrolyte tailoring to implementation," Nanoscale Advances, vol. 5, no. 3, pp. 615-626, 2023.
[10] N. Kumar, S.-B. Kim, S.-Y. Lee, and S.-J. Park, "Recent advanced supercapacitor: a review of storage mechanisms, electrode materials, modification, and perspectives," Nanomaterials, vol. 12, no. 20, p. 3708, 2022.
[11] S. Rudra, H. W. Seo, S. Sarker, and D. M. Kim, "Supercapatteries as hybrid electrochemical energy storage devices: current status and future prospects," Molecules, vol. 29, no. 1, p. 243, 2024.
[12] A. Berrueta, A. Ursua, I. San Martin, A. Eftekhari, and P. Sanchis, "Supercapacitors: electrical characteristics, modeling, applications, and future trends," Ieee Access, vol. 7, pp. 50869-50896, 2019.
[13] E. S. Greenhalgh, S. Nguyen, M. Valkova, N. Shirshova, M. S. Shaffer, and A. Kucernak, "A critical review of structural supercapacitors and outlook on future research challenges," Composites Science and Technology, vol. 235, p. 109968, 2023.
[14] A. Kashtiaray and A. Maleki, "Supercapacitors: Fundamentals, Design, Electrolytes and Interfaces," 2025.
[15] J.-H. Lee, G. Yang, C.-H. Kim, R. L. Mahajan, S.-Y. Lee, and S.-J. Park, "Flexible solid-state hybrid supercapacitors for the internet of everything (IoE)," Energy & Environmental Science, vol. 15, no. 6, pp. 2233-2258, 2022.
[16] A. Mendhe and H. Panda, "A review on electrolytes for supercapacitor device," Discover Materials, vol. 3, no. 1, p. 29, 2023.
[17] A. Patel, S. K. Patel, R. Singh, and R. Patel, "Review on recent advancements in the role of electrolytes and electrode materials on supercapacitor performances," Discover Nano, vol. 19, no. 1, p. 188, 2024.
[18] S. Samantaray, D. Mohanty, I.-M. Hung, M. Moniruzzaman, and S. K. Satpathy, "Unleashing recent electrolyte materials for next-generation supercapacitor applications: a comprehensive review," Journal of Energy Storage, vol. 72, p. 108352, 2023.
[19] B. Pal, S. Yang, S. Ramesh, V. Thangadurai, and R. Jose, "Electrolyte selection for supercapacitive devices: a critical review," Nanoscale advances, vol. 1, no. 10, pp. 3807-3835, 2019.
[20] M. S. Ahmed, M. Islam, B. Raut, S. Yun, H. Y. Kim, and K.-W. Nam, "A comprehensive review of functional gel polymer electrolytes and applications in lithium-ion battery," Gels, vol. 10, no. 9, p. 563, 2024.
[21] S. Alipoori, S. Mazinani, S. H. Aboutalebi, and F. Sharif, "Review of PVA-based gel polymer electrolytes in flexible solid-state supercapacitors: Opportunities and challenges," journal of energy storage, vol. 27, p. 101072, 2020.
[22] S. Alipoori, S. H. Aboutalebi, and M. Barsbay, "Enhancing the performance of solid-state supercapacitors: Optimizing the molecular interactions in flexible gel polymer electrolytes," Journal of Solid State Electrochemistry, vol. 28, no. 8, pp. 2643-2657, 2024.
[23] S. B. Aziz, O. G. Abdullah, D. M. Aziz, M. B. Ahmed, and R. T. Abdulwahid, "Energy Storage Performance of Plasticized PVA-Based Electrolyte: Electrical and Electrochemical Properties," ACS Applied Electronic Materials, vol. 6, no. 11, pp. 7763-7780, 2024.
[24] A. Hany, M. Mousa, and T. El-Essawy, "Studies on AC electrical conductivity, dielectric properties and ion transport in PVA polymeric electrolytes," Journal of Basic and Environmental Sciences, vol. 4, no. 4, pp. 298-304, 2017.
[25] H. Yu, J. Wu, L. Fan, K. Xu, X. Zhong, Y. Lin, and J. Lin, "Improvement of the performance for quasi-solid-state supercapacitor by using PVA–KOH–KI polymer gel electrolyte," Electrochimica Acta, vol. 56, no. 20, pp. 6881-6886, 2011.
[26] J. Hu, K. Xie, X. Liu, S. Guo, C. Shen, X. Liu, X. Li, J.-g. Wang, and B. Wei, "Dramatically enhanced ion conductivity of gel polymer electrolyte for supercapacitor via h-BN nanosheets doping," Electrochimica Acta, vol. 227, pp. 455-461, 2017.
[27] C. Zhao, C. Wang, Z. Yue, K. Shu, and G. G. Wallace, "Intrinsically stretchable supercapacitors composed of polypyrrole electrodes and highly stretchable gel electrolyte," ACS applied materials & interfaces, vol. 5, no. 18, pp. 9008-9014, 2013.
[28] K.-J. Wu, W.-B. Young, and C. Young, "Structural supercapacitors: A mini-review of their fabrication, mechanical & electrochemical properties," Journal of Energy Storage, vol. 72, p. 108358, 2023.
[29] X. Liu, W. Xu, D. Zheng, Z. Li, Y. Zeng, and X. Lu, "Carbon cloth as an advanced electrode material for supercapacitors: progress and challenges," Journal of Materials Chemistry A, vol. 8, no. 35, pp. 17938-17950, 2020.
[30] Y. Wang, H. Li, B. Cui, X. Xu, and Y. Wang, "Simple mixed-acid-treated carbon fiber electrodes with oxygen-containing functional groups for flexible supercapacitors," Journal of Composites Science, vol. 7, no. 6, p. 231, 2023.
[31] M. S. Ansari, S. Zafar, and H. Pathak, "A comprehensive review of surface modification techniques for carbon fibers for enhanced performance of resulting composites," Results in Surfaces and Interfaces, vol. 12, p. 100141, 2023.
[32] H. Qian, H. Diao, N. Shirshova, E. S. Greenhalgh, J. G. Steinke, M. S. Shaffer, and A. Bismarck, "Activation of structural carbon fibres for potential applications in multifunctional structural supercapacitors," Journal of colloid and interface science, vol. 395, pp. 241-248, 2013.
[33] H. Qian, A. R. Kucernak, E. S. Greenhalgh, A. Bismarck, and M. S. Shaffer, "Multifunctional structural supercapacitor composites based on carbon aerogel modified high performance carbon fiber fabric," ACS applied materials & interfaces, vol. 5, no. 13, pp. 6113-6122, 2013.
[34] N. Shirshova, H. Qian, M. Houllé, J. H. Steinke, A. R. Kucernak, Q. P. Fontana, E. S. Greenhalgh, A. Bismarck, and M. S. Shaffer, "Multifunctional structural energy storage composite supercapacitors," Faraday discussions, vol. 172, pp. 81-103, 2014.
[35] M. Shoeb, F. Mashkoor, H. Jeong, A. H. Anwer, S. Zhu, M. Z. Ansari, and C. Jeong, "VARTM-assisted high-performance solid-state structural supercapacitor device based on the synergistic effect of Ni (OH) 2-Co3S4 nanocomposite for widened potential window and charge storage mechanism," Chemical Engineering Journal, vol. 466, p. 143116, 2023.
[36] M. Kang, W. Lee, and H. Hahn, "Analysis of vacuum bag resin transfer molding process," Composites Part A: Applied science and manufacturing, vol. 32, no. 11, pp. 1553-1560, 2001.
[37] V. K. Dhimole, P. Serrao, and C. Cho, "Review and suggestion of failure theories in voids scenario for VARTM processed composite materials," Polymers, vol. 13, no. 6, p. 969, 2021.
[38] T. M. Higgins and J. N. Coleman, "Avoiding resistance limitations in high-performance transparent supercapacitor electrodes based on large-area, high-conductivity PEDOT: PSS films," ACS applied materials & interfaces, vol. 7, no. 30, pp. 16495-16506, 2015.
[39] K.-C. Tsay, L. Zhang, and J. Zhang, "Effects of electrode layer composition/thickness and electrolyte concentration on both specific capacitance and energy density of supercapacitor," Electrochimica Acta, vol. 60, pp. 428-436, 2012.
[40] X. Liu, X. Dai, G. Wei, Y. Xi, M. Pang, V. Izotov, N. Klyui, D. Havrykov, Y. Ji, and Q. Guo, "Experimental and theoretical studies of nonlinear dependence of the internal resistance and electrode thickness for high performance supercapacitor," Scientific Reports, vol. 7, no. 1, p. 45934, 2017.
[41] L. Jiang, S. Wang, F. Meng, J. Hu, and X. Yan, "The influence of electrode geometry on the electrochemical performance of fabric-based screen-printed coplanar supercapacitors," Journal of Energy Storage, vol. 73, p. 109001, 2023.
[42] H. Zhou, H. Li, L. Li, T. Liu, G. Chen, Y. Zhu, L. Zhou, and H. Huang, "Structural composite energy storage devices—a review," Materials Today Energy, vol. 24, p. 100924, 2022.
[43] K. Wang, Z. Wang, C. Wang, X. Zhang, and L. Wu, "Carbon fiber electrodes for composite structural supercapacitor: Preparation and modification methods," Journal of Energy Storage, vol. 98, p. 113129, 2024.
[44] C. Ruan and Y. Xie, "Electrochemical performance of activated carbon fiber with hydrogen bond-induced high sulfur/nitrogen doping," RSC advances, vol. 10, no. 62, pp. 37631-37643, 2020.
[45] H. Zhou, Y. Su, J. Zhang, H. Li, L. Zhou, and H. Huang, "A novel embedded all-solid-state composite structural supercapacitor based on activated carbon fiber electrode and carbon fiber reinforced polymer matrix," Chemical Engineering Journal, vol. 454, p. 140222, 2023.
[46] H. Ur-Rehman, A. Shuja, M. Ali, M. S. Khan, I. Murtaza, and H. Meng, "Investigation of charge and current dynamics in PVA–KOH gel electrolyte-based supercapacitor," Journal of Materials Science: Materials in Electronics, vol. 33, no. 5, pp. 2322-2335, 2022.
[47] B. Dharmasiri, F. Stojcevski, K. A. S. Usman, S. A. Qin, J. M. Razal, E. H. Doeven, P. S. Francis, T. U. Connell, Y. Yin, and G. G. Andersson, "Flexible carbon fiber based structural supercapacitor composites with solvate ionic liquid-epoxy solid electrolyte," Chemical Engineering Journal, vol. 455, p. 140778, 2023.
[48] J. Qiu, J. Li, Z. Yuan, H. Zeng, and X. Chen, "Surface modification of carbon fibres for interface improvement in textile composites," Applied composite materials, vol. 25, no. 4, pp. 853-860, 2018.
[49] K. Kim, M. Kim, G. Kim, and D. Kim, "The effect of chemical and thermal treatment for desizing on the properties and chemical functional groups of carbon fiber," Materials, vol. 16, no. 20, p. 6732, 2023.
[50] C. Qiu, L. Jiang, Y. Gao, and L. Sheng, "Effects of oxygen-containing functional groups on carbon materials in supercapacitors: A review," Materials & Design, vol. 230, p. 111952, 2023.
[51] Y. Ding, G. Qi, Q. Cui, J. Yang, B. Zhang, and S. Du, "High-performance multifunctional structural supercapacitors based on in situ and ex situ activated-carbon-coated carbon fiber electrodes," Energy & Fuels, vol. 36, no. 4, pp. 2171-2178, 2022.
[52] Y. G. Cho, C. Hwang, D. S. Cheong, Y. S. Kim, and H. K. Song, "Gel/solid polymer electrolytes characterized by in situ gelation or polymerization for electrochemical energy systems," Advanced materials, vol. 31, no. 20, p. 1804909, 2019.
[53] P. Teymoory and C. Shen, "Thermally Induced Interfacial Changes of Solid Polymer Electrolytes in Electric Double-Layer Supercapacitors," ACS applied materials & interfaces, 2026.
[54] F. Baskoro, H. Q. Wong, and H.-J. Yen, "Strategic structural design of a gel polymer electrolyte toward a high efficiency lithium-ion battery," ACS Applied Energy Materials, vol. 2, no. 6, pp. 3937-3971, 2019.
[55] F. Santos, J. P. Tafur, J. Abad, and A. J. F. Romero, "Structural modifications and ionic transport of PVA-KOH hydrogels applied in Zn/Air batteries," Journal of Electroanalytical Chemistry, vol. 850, p. 113380, 2019.
[56] A. Lewandowski, K. Skorupska, and J. Malinska, "Novel poly (vinyl alcohol)–KOH–H2O alkaline polymer electrolyte," Solid state ionics, vol. 133, no. 3-4, pp. 265-271, 2000.
[57] A. D. Shuaibu, S. S. Shah, A. S. Alzahrani, and M. A. Aziz, "Advancing gel polymer electrolytes for next-generation high-performance solid-state supercapacitors: A comprehensive review," Journal of Energy Storage, vol. 107, p. 114851, 2025.
[58] W.-H. Li, W.-H. Deng, G.-E. Wang, and G. Xu, "Conductive MOFs," EnergyChem, vol. 2, no. 2, p. 100029, 2020.
[59] Y.-R. Lee, K.-J. Wu, W.-B. Young, and C. Young, "Development of High-Performance Large-Scale Structural Supercapacitors via the Resin Infusion Process and Encapsulation Process," ACS Applied Energy Materials, vol. 7, no. 18, pp. 8066-8076, 2024.
[60] C.-C. Wu and W.-B. Young, "On the fabrication processes of structural supercapacitors by resin transfer molding and vacuum-assisted resin transfer molding," Journal of Composites Science, vol. 8, no. 10, p. 418, 2024.
[61] 范鈞隆, "結構型超級電容器串/並聯封裝之電化學及機械性質探討," 碩士, 航空太空工程學系, 國立成功大學, 2025.
[62] N. O. Laschuk, E. B. Easton, and O. V. Zenkina, "Reducing the resistance for the use of electrochemical impedance spectroscopy analysis in materials chemistry," RSC advances, vol. 11, no. 45, pp. 27925-27936, 2021.
[63] A. Noori, M. F. El-Kady, M. S. Rahmanifar, R. B. Kaner, and M. F. Mousavi, "Towards establishing standard performance metrics for batteries, supercapacitors and beyond," Chemical Society Reviews, vol. 48, no. 5, pp. 1272-1341, 2019.
[64] M. Valkova, S. Nguyen, E. Senokos, S. Razavi, A. Kucernak, D. Anthony, M. Shaffer, and E. Greenhalgh, "Current collector design strategies: The route to realising scale-up of structural power composites," Composites Science and Technology, vol. 236, p. 109978, 2023.
[65] W. Zschiebsch, Y. Sturm, M. Kucher, D. P. Hedayati, T. Behnisch, N. Modler, and R. Böhm, "Multifunctionality analysis of structural supercapacitors—a review," Materials, vol. 17, no. 3, p. 739, 2024.