碳结构对铝离子二次电池电化学性能的影响

摘要

为了研究碳材料结构对铝离子二次电池充放电性能的影响,选取热解石墨、中间相炭微球、树脂碳三种不同碳材料作为正极,高纯铝箔作为负极,离子液([EMIM]Cl-AlCl3)作为电解液,进行恒流充放电性能研究.研究结果表明:不同结构的碳材料对铝离子二次电池的充放电性能有较大的影响.其中以含石墨化碳成分的热解石墨和中间相炭微球作为正极材料时,铝离子二次电池在低电流密度下(30 mA/g)具有较高的放电比容量(分别为75、68 mAh/g)和相对较好的库仑效率(分别为83％、82％).而以硬碳为主要成分的树脂碳作为正极材料时,铝离子二次电池的放电比容量较低,在30mA/g的电流密度下放电比容量仅为58 mAh/g左右,且库仑效率极低,仅为45％.%In order to study the effect of carbon material structure on the electrochemical property of rechargeable aluminium ion battery,pyrolytic graphite,mesocarbon microbeads and resin carbon were selected as cathode materials,high purity aluminum foil was selected as anode material,ionic liquid ([EMIM]Cl-AlCl3) was selected as the electrolyte,and the galvanostatic charge and discharge of rechargeable aluminum batteries were conducted.The results show that the different structure of carbon material has great influence on the electrochemical property of rechargeable aluminum ion battery.The rechargeable aluminium ion batteries with pyrolytic graphite and mesocarbon microbeads as the cathode material which both contain graphitized carbon have high discharge specific capacity (75 and 68 mAh/g respectively) and relatively good coulomb efficiency (83％ and 82％ respectively) at low current density (30 mA/g).Besides,the rechargeable aluminium ion battery with resin carbon as the cathode material which the main component is hard carbon has low discharge specific capacity of 58 mAh/g at the current density of 30 mA/g and extremely low coulomb efficiency of 45％.