活性炭涂层改性锌负极与电化学性能研究

Study on electrochemical properties of zinc anode modified by activated carbon coating

提出一种新型的可充电水性锌离子电池(AZIB),该电池由涂有活性炭的锌作为负极,氧化镍干凝胶复合电极作为正极。扫描电子显微镜表明,由于活性炭疏松多孔的结构,可以有效抑制锌枝晶的堆积生长。同时活性炭可以形成导电网络,从而大大扩大电活性表面积。在充放电循环测试中,活性炭涂层锌负极在50次循环后依然具有80%以上的容量。进一步证明了活性炭涂层的有效性。在对称电池测试中,电流密度为1 mA cm^(-2),比容量为1 mAh cm^(-2)的条件下,涂层锌阳极循环160 h仍可实现稳定的镀锌/剥离过程且无短路现象。表现出优异的循环稳定性,并且没有明显的极化。该项工作为开发可充电锌离子电池提供了一个新的视角,并将加快可充电ZIB的实际应用。

We report a novel rechargeable aqueous Zn-ion battery(AZIB)that consist of Zn coated with active carbon(AC)as the anode and nickle oxide dry gel composite electrode as the cathode.SEM observations reveal that zinc dendrite accumulation can be effectively inhibited due to the loose and porous structure of activated carbon.The active carbon can form an electrically conductive network,thus greatly enlarging the electroactive surface area.With the modified anode,the battery gives a high capacity retention of 80%after 50 cycles.The effectiveness of activated carbon coating was further proved.In the symmetrical battery tests,the modified anode can achieve stable plating/stripping which is 160 h circulation without short circuit at the electric current density of 1 mA cm^(-2),specific capacity of 1 mAh cm^(-2).Electrochemical tests reveal that the prepared material has excellent rate capability and cycling stability without obvious polarization.Our work provides a new perspective in developing rechargeable ZIBs and would greatly accelerate the practical applications of rechargeable ZIBs.