摘要
燃料电池是一种能量转化效率高、对环境友好的清洁能源装置,但现有燃料电池需要质子交换膜及燃料储存供应系统,限制了其便携化、微型化的发展.水凝胶作为一种三维交联聚合物网络固态电解质,内部多孔交联结构可实现吸水保水能力,在大比表面上可实现快速的物质传输.为简化燃料电池结构,提高系统便携化、微型化,本文使用循环冻融法制备聚乙烯醇水凝胶,利用水凝胶的保水性和离子导电性,将水凝胶作为燃料电池固态电解质,实现了燃料/电解液储供一体化.本文探究了制备条件对水凝胶电解质溶胀性能及导电性能的影响,结果表明,质量分数为5%的聚乙烯醇水凝胶可达到45%的溶胀率及173.61mS/cm的离子电导率,所组装的燃料电池系统功率密度和电流密度分别达到2.5mW/cm^(2)和15.2mA/cm^(2),使得水凝胶有望提高微型燃料电池便携化.
The development of modern electronic equipment has promoted the requirement of portable energy conversion devices.Fuel cell technology provides clean energy,which is pollution-free and environmentally friendly.It has several advantages,including instant charge and discharge,high energy conversion efficiency,and easy integration.However,some disadvantages,such as high membrane cost,membrane aging degradation,water management,and extra ohmic resistance,always accompany the conventional proton exchange membrane fuel cells.In addition,the need for fuel tanks increases the system cost and complexity and is unfavorable for miniaturization.Meanwhile,the consumption of additional pump power to supply fuel can reduce the net output power.Hydrogel is a solid-state electrolyte crosslinked via a three-dimensional(3D)polymer network.The porous structure possesses the abilities of water absorption and retention and enables fast mass transport on a large surface.To simplify the fuel cell system and improve its portability,a miniature fuel cell integrated with the fuel/electrolyte is proposed,complemented by the water retention and ionic conductivity of the hydrogel.Polyvinyl alcohol(PVA)hydrogel is prepared via cyclic freezing and thawing processes.The effects of the fabrication parameters,such as swelling and conductivity of the hydrogel electrolyte,are discussed,and the fuel cell equipped with hydrogel is set up.The micromorphology and element distribution of PVA hydrogel are evaluated via physical characterization.PVA hydrogel has an abundant 3D-network porous structure.PVA polymer chain is uniformly crosslinked,and C and O elements are evenly distributed on the hydrogel skeleton.Fourier transform infrared results reveal numerous hydrophilic groups in PVA hydrogel,including-OH and C-O,contributing to the high aqueous electrolyte absorption ability.The effect of fabrication parameters on the swelling properties of PVA hydrogel is studied.The high concentration and efficient repetitive freezing-thawing can improve the crosslin
作者
邢楷
杨扬
朱恂
叶丁丁
陈蓉
廖强
Kai Xing;Yang Yang;Xun Zhu;Dingding Ye;Rong Chen;Qiang Liao(Key Laboratory of Low-grade Energy Utilization Technologies and Systems,Ministry of Education,Chongqing University,Chongging 400030,China;Institute of Engineering Thermophysics,School of Energy and Powering Engineering,Chongqing University Chongqing 400030,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2022年第28期3487-3496,共10页
Chinese Science Bulletin
基金
国家自然科学基金创新研究群体项目(52021004)
国家自然科学基金重点国际(地区)合作研究项目(51620105011)
国家自然科学基金面上项目(52176055)资助。
