A series of single phase LixNi0.8-yCo-（0.2）ZnyOp （0.96 ≤ x ≤ 1.10, 0 ≤ y ≤ 0.05, 2 ≤ p ≤ 2（1+ y） ） （different in the y values） were synthesized by a two step solid state reaction method, in which LiOH...A series of single phase LixNi0.8-yCo-（0.2）ZnyOp （0.96 ≤ x ≤ 1.10, 0 ≤ y ≤ 0.05, 2 ≤ p ≤ 2（1+ y） ） （different in the y values） were synthesized by a two step solid state reaction method, in which LiOH· H2O, Zn doped spherical Ni（OH）2 and Co2O3 were used as the precursors. The ICP AES analyses proved that the Zn doped compounds synthesized had the nonstoichiometric form. The results of the XRD, SEM identified that the uniform particles of the as prepared materials having a good layered structure were fine, narrowly distributed and well crystallized. The electrochemical performance test was carried out and the results showed that the as prepared Zn doped materials had not only a high capacity, but also a better cycling stability characterization than the un doped one. The Li1.06Ni0.75Co0.22Zn0.03O2.03 material has an initial reversible capacity as high as 160.5mAh· g- 1; and a first discharge efficiency 89.2% , and exhibits satisfactory cyclic stability with 90% retainable capacity after 50 cycles.展开更多
Multiwalled carbon nanotubes (MWNTs) were used as the conductive additive in the electrode materials. The electrochemical properties of supercapacitors based on LiNi0.8Co0.2O2 / MWNTs composite and LiNi0.8Co0.2O2/acet...Multiwalled carbon nanotubes (MWNTs) were used as the conductive additive in the electrode materials. The electrochemical properties of supercapacitors based on LiNi0.8Co0.2O2 / MWNTs composite and LiNi0.8Co0.2O2/acetylene black composite and MWNTs in 1.0 mol·L-1 LiClO4 / EC+DEC [V(EC)∶V(DEC)=1∶1] electrolyte were investigated by means of constant charge/discharge current tests, respectively. The experimental results show that the LiNi0.8Co0.2O2 / MWNTs composite has better performance than that of others, and the maximum specific capacitance of the supercapacitor can reach 271.6 F·g-1, while the energy density is up to 339.5 Wh·kg-1. Furthermore, it is remarkable that the performance of MWNTs is better than that of acetylene black as the conductive additive.展开更多
文摘A series of single phase LixNi0.8-yCo-（0.2）ZnyOp （0.96 ≤ x ≤ 1.10, 0 ≤ y ≤ 0.05, 2 ≤ p ≤ 2（1+ y） ） （different in the y values） were synthesized by a two step solid state reaction method, in which LiOH· H2O, Zn doped spherical Ni（OH）2 and Co2O3 were used as the precursors. The ICP AES analyses proved that the Zn doped compounds synthesized had the nonstoichiometric form. The results of the XRD, SEM identified that the uniform particles of the as prepared materials having a good layered structure were fine, narrowly distributed and well crystallized. The electrochemical performance test was carried out and the results showed that the as prepared Zn doped materials had not only a high capacity, but also a better cycling stability characterization than the un doped one. The Li1.06Ni0.75Co0.22Zn0.03O2.03 material has an initial reversible capacity as high as 160.5mAh· g- 1; and a first discharge efficiency 89.2% , and exhibits satisfactory cyclic stability with 90% retainable capacity after 50 cycles.
文摘Multiwalled carbon nanotubes (MWNTs) were used as the conductive additive in the electrode materials. The electrochemical properties of supercapacitors based on LiNi0.8Co0.2O2 / MWNTs composite and LiNi0.8Co0.2O2/acetylene black composite and MWNTs in 1.0 mol·L-1 LiClO4 / EC+DEC [V(EC)∶V(DEC)=1∶1] electrolyte were investigated by means of constant charge/discharge current tests, respectively. The experimental results show that the LiNi0.8Co0.2O2 / MWNTs composite has better performance than that of others, and the maximum specific capacitance of the supercapacitor can reach 271.6 F·g-1, while the energy density is up to 339.5 Wh·kg-1. Furthermore, it is remarkable that the performance of MWNTs is better than that of acetylene black as the conductive additive.
