Patent ID: 6506519
Filing Date: 2003-01-14
Classification: H01M,Y02E,Y10T

Abstract:
A nonaqueous secondary battery comprising a negative electrode comprising a carbonaceous material in which the ratio RG=Gs/Gb of the degree of graphitization Gs of the carbonaceous material, determined by a surface-enhanced Raman spectrum, to the degree of graphitization Gb, determined by a Raman spectrum measured using argon laser light, is at least 4.5, based on the following conditions:Gb=Hbb/Hba; andGs=Hsb/Hsa; whereinHba is the height of a peak lying in a range of 1,580 cmâˆ’1 to 1,620 cmâˆ’1 in a Raman spectrum which is measured using an argon laser Raman spectrometer of a wavelength of 514.5 nm and a wavelength resolution of 4 cmâˆ’1; Hbb is the height of a peak lying in a range of 1,350 cmâˆ’1 to 1,400 cmâˆ’1 in a Raman spectrum which is measured using an argon laser Raman spectrometer of a wavelength of 514.5 nm and a wavelength resolution of 4 cmâˆ’1; Hsa is the height of a peak lying in a range of 1,580 cmâˆ’1 to 1,620 cmâˆ’1 in a surface-enhanced Raman spectrum which is measured using an argon laser Raman spectrometer of a wavelength of 514.5 nm and a wavelength resolution of 4 cmâˆ’1 when silver having a thickness of 10 nm is deposited on the carbonaceous material; and Hsb is the height of a peak lying in a range of 1,350 cmâˆ’1 to 1,400 cmâˆ’1 in a surface-enhanced Raman spectrum which is measured using an argon laser Raman spectrometer of a wavelength of 514.5 nm and a wavelength resolution of 4 cmâˆ’1 when silver having a thickness of 10 nm is deposited on the carbonaceous material.