Development of a bipolar plate with high conductivity and good antioxidant ability is significant for the vanadium redox flow battery (VRB) and other mass electricity storage equipments. Conductive plastic plate can be made by adding conductive fillers, such as carbon black (CB), graphite (GP), and expandable graphite (EG), into polymer matrixes. This study investigated the influences of different conductive fillers and their compositions, size, distribution method on the conductivity of the prepared bipolar plate, besides, the XRD and SEM were used to characterize the fillers and their morphologies in polymer matrixes. The filler patieles with smaller size is benefit for its distribution to improve conductivity, and the mixing method of mixing the filler with polymer in solvent or suspended solution provided an approximate result, and however, dispersion in a suspended solution is more suitable for process scaling-up. Bipolar plate with 50％ (wt) and 400 mesh EG has conductivity of 92 S·cm-1, bending strength of 52 MPa. Since the bipolar plate also shows excellent properties in rejecting the permeation of vanadium ions and resisting erosion in strong oxidant, it is promising for application in VRB.%研究导电性高、耐腐蚀性强的双极板对发展全钒液流电池等大规模蓄电储能装备具有重要意义.在聚偏氟乙烯(PVDF)高分子基体中加入炭黑(CB)、鳞片石墨(GP)、膨胀石墨(EG)等导电填料,均匀分散后制备导电双极板,考察了导电填料种类、含量、粒度大小、分散方式对双极板导电性能的影响规律,利用x射线衍射(XRD)和扫描电子显微镜(SEM)表征导电填料本体和微观分散形态.结果表明使用粒径较小的可膨胀石墨有利于提高导电率,溶解法和悬浮液法均能保证导电填料的良好分散,所制备的双极板具有相近的导电性能,但后者易于进行大规模工业化生产.使用400目可膨胀石墨为导电填料制作双极板,当其质量含量为50%时,电导率达到92 S.cm-1,弯曲强度为52 MPa.所研究的导电塑料双极板能够完全阻隔钒离子渗透,具有良好抗氧化性能,有望在全钒液流电池的实际开发过程中应用.
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