What types of conductive agents are used in sodium-ion batteries?

量产导电剂全部为碳基材料，分四类按需复配使用。第一类颗粒炭黑（乙炔黑、SP 炭黑）成本最低，分散简单，填充缝隙搭建基础导电网络，通用基础料。第二类碳纳米管 CNT 一维长管，少量添加即可大幅降内阻，适配高倍率、高能量电芯。第三类石墨烯二维片材面接触导电，效率顶尖，用于高端长循环储能，但原料价格偏高。第四类复合导电剂炭黑   CNT   石墨烯，兼顾成本与导电能力，是当前工厂量产主流方案。不同正极匹配不同配比：普鲁士蓝导电弱，增加 CNT、石墨烯；聚阴离子导电性最差，必须搭配包覆碳与复合导电剂才能满足循环需求。

All mass-produced conductive agents are carbon-based, divided into four categories for compound use. 1. Granular carbon black (acetylene black, SP black): lowest cost, easy dispersion, fills gaps to build basic conductive networks as universal base materials. 2. Carbon nanotubes (CNTs): one-dimensional long tubes that greatly cut resistance with tiny dosage, suitable for high-rate, high-energy cells. 3. Graphene: two sheets with superior surface conduction for high-end long-cycle energy storage at high raw material costs. 4. Composite agents (carbon black   CNT   graphene): balance cost and conductivity, the mainstream mass-production formula of factories. Different cathodes require different ratios: low-conductivity Prussian blue needs extra CNT and graphene; polyanions with the weakest conductivity must pair coated carbon and composite conductive agents to meet cycling requirements.