EP0495613A2
Expired / Lapsed
EP
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Lithium secondary battery and carbonaceous material useful therein
Assignee: Toshiba Corp
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Filing: 1992-01-14
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Granted: —
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Expires: 2012-01-14
Abstract
Abstract A lithium secondary battery, comprising: a vessel; a positive electrode containing an active material housed in the vessel; a lithium ion conductive electrolyte in the vessel, and a negative electrode arranged in the vessel containing carbonaceous material spherical particles as active material that absorbs and discharges lithium ions, the carbonaceous material spherical particles containing a graphite-like layered structure part and a turbulence-layered structure part, fine structures of the carbonaceous material spherical particle being arranged in point-orientation. There is also provided a process for making carbonaceous material for a negative electrode of a lithium secondary battery comprising the step of heat-treating for carbonizing a spherical particle or a fibre, the heat-treating step including one of the steps of carbonizing a mesophase small spherical particle or a mesophase pitch fibre in an inert gas or a vacuum at a temperature of more than 1200°C up to 2500°C.
Inventors
- 👤 Norio C/O Intellectual Property Division Takami
- 👤 Takahisa C/O Intellectual Property Div. Ohsaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 14:17
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/36; H01M4/58; H01M4/583; H01M4/587; H01M10/00; H01M10/05; H01M10/052; H01M10/0525; H01M10/056; H01M10/0564; H01M10/0566; H01M10/0569; H01M10/058; H01M10/0587; H01M2300/00; H01M2300/0017; H01M2300/0025; H01M4/13; H01M4/131; H01M4/133; H01M6/00; H01M6/04; H01M6/06; H01M6/10; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
76 words
A lithium secondary battery, comprising: a vessel; a positive electrode containing an active material housed in the vessel; a lithium ion conductive electrolyte in the vessel, and a negative electrode arranged in the vessel containing carbonaceous material spherical particles as active material that absorbs and discharges lithium ions, the carbonaceous material spherical particles containing a graphite-like layered structure part and a turbulence-layered structure part, fine structures of the carbonaceous material spherical particle being arranged in point-orientation.
Claim 2
Dependent Claim
29 words
A battery as claimed in claim 1, wherein the mean value of the (002) face distance (d₀₀₂) in the carbonaceous material spherical particle is 0.337 nm to 0.380 nm.
Claim 3
Dependent Claim
31 words
A battery as claimed in claim 1 or 2, wherein the mean size of the crystal lattice (Lc) along the C-axis in the spherical particle is 1 nm to 25 nm.
Claim 4
Dependent Claim
40 words
A battery as claimed in any preceding claim, wherein the Raman spectrum ratio R₁/R₂ of the spherical particles is 0.5 to 1.5 where: R₁ is a peak value at 1360⁻¹ cm, and R₂ is a peak value at 1580⁻¹ cm.
Claim 5
Dependent Claim
25 words
A battery as claimed in any preceding claim, wherein the atomic ratio of hydrogen to carbon (H/C) in the spherical particles is less than 0.15.
Claim 6
Dependent Claim
22 words
A battery as claimed in any preceding claim, wherein the average size of the spherical particles is 0.5 µm to 100 µm.
Claim 7
Dependent Claim
27 words
A battery as claimed in any preceding claim wherein the ratio of the minor radius to the major radius of the spherical particles is at least 1/10.
Claim 8
Dependent Claim
25 words
A battery as claimed in any preceding claim, wherein the spherical particles have an exothermic peak at 900°C or less measured by differential thermal analysis.
Claim 9
Dependent Claim
75 words
A lithium secondary battery, comprising: a vessel; a positive electrode containing an active material housed in the vessel; a lithium ion conductive electrolyte in the vessel, and, a negative electrode arranged in the vessel containing carbonaceous material fibres as active material that absorbs and discharges lithium ions, the carbonaceous material fibres containing a graphite-like layered structure part and a turbulence-layered structure part both having fine structures arranged in lamellar type structure or Brooks-Taylor type structure.
Claim 10
Dependent Claim
28 words
A battery as claimed in claim 9, wherein the mean value of the (002) face distance (d₀₀₂) in the carbonaceous material fibres is 0.337 nm to 0.380 nm.
Claim 11
Dependent Claim
31 words
A battery as claimed in claim 9 or 10, wherein the mean size of the crystal lattice (Lc) along the C-axis direction in the fibres is 1 nm to 25 nm.
Claim 12
Dependent Claim
43 words
A battery as claimed in any one of claims 9 to 11, wherein the Raman spectrum ratio R₁/R₂ of the fibres is 0.5 to 1.5 where; R₁ is a peak value at 1360⁻¹ cm, and R₂ is a peak value at 1580⁻¹ cm.
Claim 13
Dependent Claim
26 words
A battery as claimed in any one of claims 9 to 12, wherein the atomic ratio of hydrogen/carbon (H/C) of the fibres is less than 0.15.
Claim 14
Dependent Claim
38 words
A battery as claimed in any one of claims 9 to 13, wherein the average diameter of the fibres is 1 µm to 100 µm and the average length of the fibres is 1 µm to 200 µm.
Claim 15
Dependent Claim
28 words
A battery as claimed in any one of claims 9 to 14, wherein the fibres have an exothermic peak at 900°C or less measured by differential thermal analysis.
Claim 16
Dependent Claim
52 words
A battery as claimed in any preceding claim, wherein the lithium ion conductive electrolyte comprises solvent containing ethylene carbonate, propylene carbonate and at least one of : 1,2-dimethoxy-ethane, 1,2-diethoxyethane, diethylcarbonate, dimethoxymethane, γ-butyrolactone and tetrahydrofuran, and comprises electrolytic salt comprising at least one of: lithium borofluoride, lithium phosphate hexafluoride and lithium trifluoromet asulfonate.
Claim 17
Dependent Claim
24 words
A battery as claimed in claim 16, wherein the ratio of at least one compound in the solvent is 40 volume % or less.
Claim 18
Dependent Claim
65 words
A process for making carbonaceous material for a negative electrode of a lithium secondary battery comprising the step of heat-treating for carbonizing a spherical particle or a fibre, the heat-treating step including one of the steps of carbonizing a mesophase small spherical particle or a mesophase pitch fibre in an inert gas or a vacuum at a temperature of more than 1200°C up to 2500°C.
Claim 19
Dependent Claim
44 words
A process as claimed in claim 18, wherein the step of heat-treating also includes the step of further heating the carbonacerus material in the presence of oxygen at 300-800°C for about 1-10 hours, after the step of heating in the inert gas or vacuum.
Claim 20
Dependent Claim
65 words
A process for making carbonaceous material for a negative electrode for a lithium secondary battery comprising the step of heat-treating for carbonizing a spherical particle or a fibre, the heat treating step including one of the steps of carbonizing a mesophase small spherical particle or a mesophase pitch fibre in an inert gas or a vacuum at a temperature of 600°C to less than 1200°C.
Claim 21
Dependent Claim
24 words
An electrode for a lithium battery comprising carbonaceous material prepared according to a process as claimed in any one of claims 18 to 20.
References Cited (Backward Citations)
EP0201038A1
Cited
WO1990013924A2
Cited
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