为了解决MnO_(2)正极在水系锌离子电池中循环稳定性差及离子运输缓慢等问题,采用直写成型技术制备高精度定制的3D打印MnO_(2)正极。流变测试表明,打印墨水表现出剪切变稀行为,存储模量平台值高达10^(5) Pa。SEM图像显示,100次循环后该定制网-层状结构保持完整。具有良好力学强度的3D结构有利于降低电极内残余应力,同时提供更大的比表面积。所得的3D打印正极在50 m A/g的电流密度下循环110次后,比容量为对照传统2D电极的4倍。采用多种非原位技术系统研究了3D打印电池的可逆Mn^(2+)/Mn^(4+)双氧化还原储能机制。
To solve the problem of drying gelcast green body, the thermoresponsive gel system which contains macromonomer graft chains was used in gelcasting of ZnO. The effects of the amount and length of graft chains macromonomer PIPAAm, the total amount of organic matters, and the solid loading on the rheological properties of suspensions were investigated, and the drying mechanism of gelcast green body was analyzed. The results show that ZnO suspensions with the gel system still display shear- thinning rheological behavior, but its viscosity increases with increasing the addition amount and relative molecular mass of PIPAAm graft chain, and the total organic matter content. The PIPAAm graft chains inhibit or even eliminate the formation of the ＂dense layer” on the surface of gelcast ZnO green bodies, and accelerate the drying of green bodies. The introduction of PIPAAm graft chains facilitates the shrinkage of the gelcast ZnO green bodies, which is a feasible method to increase the relative density of green bodies.
