Synthesis of nanostructured cathode materials to achieve maximum performance at high-rate charge/discharge of nickel-based secondary battery

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05654
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 36010:Inorganic compounds and inorganic materials chemistry-related
• Research Institution: University of Miyazaki
• Principal Investigator: Sakai Go 宮崎大学, 工学部, 教授 (40284567)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 水酸化ニッケル / 正極材料 / 二次電池

Outline of Final Research Achievements

The electrochemical characteristics of nickel hydroxide (Ni(OH)2) used as cathode material for nickel-based secondary batteries can be improved by controlling crystal structure as well as nano-sized structure especially for higher-charge/discharge rate. In the present study, partial substitution of nickel ion (Ni2+) by Mg enhanced reduction oxidation rate of cathode material, and the capacity of the material was improved by 10% compared with normal nickel hydroxide. Moreover, it was found that the partial substitution of octahedral sites of nickel (Ni2+) by copper (Cu+ or Cu2+) or Manganese (Mn2+) creates at least two types of interlayer spacing structure. It was also found that the charge/discharge characteristics depends on these structural characteristics. The additional partial substitution by zinc (Zn) proceeds the formation of thermally stable alpha-type structure results in increment of capacity.

Free Research Field

無機材料化学、電気化学

Academic Significance and Societal Importance of the Research Achievements

ニッケル系二次電池の正極材料として用いられるβ型水酸化ニッケルは、その構造及び特性を異種元素置換によって制御できることを明らかにしてきた。特に層状構造を有するβ型水酸化ニッケルの層間距離の変化についていくつかの重要な知見を得た。これらの知見は、エネルギーの高効率利用の観点から重要であり、特に、大容量の充放電設備として、メンテナンスフリーで一次エネルギーからの電気を利用することを想定するとその学術的意義と社会的意義は大きいと考えられる。