Satoshi Narukawa

Behaviour of various cathode materials for non-aqueous lithium cells

Abstract The reaction mechanisms with Li of various metal oxides, sulfides and a selenide in nonaqueous electrolyte have been studied by the galvanostatic method, X-ray diffraction analysis, and ion-microanalysis. As a result, cell reactions were classified into 3 types. (1) The directly reduced type: cathode materials are reduced directly to metal; CuO, etc. (2) The 2 step reaction type: reaction proceeds through intermediate products: FeS 2 (3) The solid diffusion type, based on the so-called intercalation reaction; MnO 2 , TiS 2 , etc.

A study on electrolytes for manganese dioxide-lithium cells

Abstract The physical properties of organic electrolyte used in manganese dioxide-lithium cells play a major role in determining various cell characteristics. The influence on various cell characteristics of electrolytes has been investigated with flat cells. LiCF 3 SO 3 is the suitable solute in terms of low-temperature, storage and overdischarge characteristics. Mixture of ethylene carbonate (EC), 1,2-butylene carbonate (BC) and 1,2-dimethoxyethane (DME) is the suitable solvent in terms of high-rate discharge and storage characteristics.

Development of prismatic lithium-ion cells using aluminum alloy casing

Light weight prismatic lithium-ion cells for cellular phones have been developed using an aluminum alloy case. Various kinds of aluminum alloys have been examined from the view point of the electrochemical stability, mechanical strength, the ability to be laser-welded and easy formation into a casing. An aluminum alloy with 1.1 wt.% Mn was the best candidate for the casing. The energy density of the lithium-ion cell with the aluminum alloy casing was improved by about 30% compared to the conventional steel casing.