Anodically electrochemical deposition of nanostructured nickel oxide electrode as an anode material for lithium-ion batteries

• Main Authors: Ya-Ping Lin, 林雅屏
• Other Authors: Dr. Mao-Sung Wu
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/10272842918760371942

碩士 === 國立高雄應用科技大學 === 化學工程與材料工程系 === 98 === In this research, the nanostructured nickel oxide electrodes were deposited onto the stainless steel (SS) substrate by anodic deposition for lithium-ion battery application. In order to improve the electrochemical performance of the nickel oxide electrode, monodispersed polystyrene (PS) spheres were used as a template in anodic deposition of nickel oxide. The PS template was fabricated by electrophoretic deposition (EPD). After removal of PS, the electrode was annealed at 400oC for 1 h to form macroporous NiO electrode (cubic NiO, deduced from X-ray diffraction). The electrochemical properties of the macroporous NiO electrode toward lithium were investigated. Surface morphology of the deposited NiO electrodes is platelet-like structure observed from SEM (scanning electron microscope). The pores in the electrode deposited at a high current density of 0.25 mA cm-2 are smaller than that of deposited at a lower current density of 0.05 mA cm-2. However, the surface morphology of nickel oxide electrode can be severely modified after charge and discharge cycling. The porous structure of the electrode deposited at 0.25 mA cm-2 remains unchanged, while that of deposited at 0.05 mA cm-2 is attenuated significantly. Galvanostatic charge/discharge curve of nickel oxide films (1 C current) indicates that the reversible capacity of electrodes deposited at 0.05 and 0.25 mA cm−2 are 1221 and 1294 mAh g-1, respectively. At a higher current charge/discharge (15 C), the reversible capacities of electrodes deposited at 0.05 and 0.25 mA cm-2 are 383 and 487 mAh g-1, respectively. Moreover, the nickel oxide electrode with macropores deposited at a current density of 0.25 mA cm−2 exhibits excellent electrochemical behavior toward lithium, especially during high-rate charging and discharging circumstances. The reversible capacity of electrode is increased by 15.6 % at 1 C rate, and 87 % at 15 C rate compared with the bare nickel oxide electrode (without open macropores). Therefore, we can conclude that a porous film structure with macropores is beneficial to the electrolyte transport, leading to an increase in effective specific surface areas for electrochemical reaction. As a result, the electrochemical performance of the nickel oxide electrode with open macropores is better than that of the bare nickel oxide electrode. Keywords: Anodic deposition; Nickel oxide; Lithium-ion batteries; Template; Macroporous structure.