用于聚合物镍氢电池的新型PVA/SiO2碱性微孔聚合物电解质(英文)  

Novel PVA/SiO_2 Alkaline Micro-porous Polymer Electrolytes for Polymer Ni—MH Batteries

作　　者：陆霞[1] 吴仁香[1] 李波波[1] 朱云峰[1] 李李泉[1] 

机构地区：[1]南京工业大学材料科学与工程学院,南京210009

出　　处：《化学学报》2013年第3期427-432,共6页Acta Chimica Sinica

基　　金：Project supported by National Natural Science Foundation of China(Nos.51171079,51071085);Specialized Research Fund for the Doctoral Program of High Education(No.20093221110008);Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)~~

摘　　要：采用溶胶凝胶法,结合相转移法和碱液活化法制备了PVA/SiO2碱性微孔聚合物电解质,通过SEM、XRD、交流阻抗法和循环伏安法表征了电解质的结构与电化学性能.研究表明,PVA/5ωSiO2(ω为质量分数)共混膜上的微孔大小合适,聚合物电解质的离子电导率最大可达1.62×10-2 S cm-1,电化学稳定窗口2 V以上;将PVA/SiO2碱性微孔电解质组装成聚合物镁基镍氢电池,与传统镍氢电池相比,循环稳定性大大增加.New poly（vinyl alcohol）/silica（designated as PVA/SiO2） alkaline micro-porous polymer electrolytes（AMPEs） were prepared by soaking PVA/SiO2 micro-porous composite membranes,obtained by solution casting of PVA/PEG/SiO2 membrane in acetone solution,into an electrolyte solution of 6 mol/L KOH aqueous solution.The morphology and structure of PVA/SiO2 composite polymer membranes were characterized by scanning electron microscopy（SEM） and X-Ray diffraction（XRD）.The SEM photographs showed that the nano-SiO2 filler content was a crucial issue for the well-dispersed and optimal-sized pores which could storage charge carrier durably.Meanwhile,the crystalline of PVA decreased effectively for a large number of crystal defects and free volume appeared in the interface of inorganic particles and polymer for the addition of nano-SiO2 filler.The electrochemical properties of the AMPEs were measured by the alternating current impedance（AC impedance） and the cyclic voltammetry（CV） techniques.The results indicated that the PVA/SiO2 AMPEs containing 5 ω nano-SiO2 filler exhibited good performances at room temperature,such as 1.62×10-2 S cm-1 for ionic conductivity and 2.20 V for electrochemical stability window.What’s more,we used the gravimetric method to obtain the electrolyte uptake of various PVA/SiO2 composite micro-porous polymer membranes.From the data,we learned that the maximum electrolyte uptake could reach to 102.7% and it had very relevance to the size of pores in PVA/SiO2 composite polymer membranes,and then influenced the ionic conductivity.Each polymer Ni-MH battery was assembled by three parts： the new AMPE,Mg-based hydrogen storage alloy and the commercial sintered Ni（OH）2/NiOOH electrode,in which each part did for electrolyte and diaphragm,negative electrode and positive electrode,respectively.The cycle experiments of the batteries exhibited a high first-cycle discharge capacity of 613 mAh g-1 and stable discharge capacities about 330 mAh g-1 for the following 5 cycles.The resul

关 键 词：聚乙烯醇 碱性微孔聚合物电解质 离子电导率 循环稳定性 聚合物Ni-MH电池 

分 类 号：O631.3[理学—高分子化学]