EP0617474A1
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EP
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Rechargeable lithium cell and process for making an anode for use in the cell
Assignee: Panasonic Holdings Corp
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Filing: 1994-03-16
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Granted: —
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Expires: 2014-03-16
Abstract
Abstract This invention relates to a rechargeable lithium cell comprises a cathode having a discharge potential not less than 2 V relative to a Li/Li⁺ anode, an anode capable of doping and un-doping lithium and made of a material comprising a lithium titanate having a spinnel structure and represented by the general formula, LixTiyO₄ wherein 0.8≦x≦1.4 and 1.6≦y≦2.2, a separator separating the cathode and the anode from each other, and an electrolytic solution impregnated at least in the separator and dissolving a lithium salt in a non-aqueous solvent. When subjected to X-ray diffraction analysis, the material has peaks at least at 4.84 ± 0.02 angstroms, 2.53 ± 0.02 angstroms, 2.09 ± 0.02 angstroms and 1.48 ± 0.02 angstroms and a ratio of a peak intensity at 4.84 ± 0.02 angstroms and a peak intensity at 1.48 ± 0.02 angstroms of 100:30 ±10. The material may consist of the lithium titanate or mixed crystals of the lithium titanate and rutile-type titanium dioxide. A process for making the anode is also described.
Inventors
- 👤 Nobuharu Koshiba
- 👤 Kenichi Takata
- 👤 Emi Asaka (Nee Nishimura)
- 👤 Makoto Nakanishi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 00:05
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/36; H01M4/48; H01M4/485; C; C01; C01G; C01G23/00; C01G23/003; C01G23/005; H01M10/00; H01M10/05; H01M10/052; H01M10/0525; H01M4/362; H01M4/364; C01P; C01P2006/00; C01P2006/40; H01M10/056; H01M10/0564; H01M10/0566; H01M10/0568; H01M2300/00; H01M2300/0017; H01M2300/0025; H01M4/13; H01M4/131; H01M4/139; H01M4/1391; H01M4/50; H01M4/505; H01M4/52; H01M4/525; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y02P; Y02P70/00; Y02P70/50
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
154 words
A rechargeable lithium cell which comprises a cathode which has a discharge potential not less than 2 V relative to a Li/Li⁺ anode, an anode capable of doping and un-doping lithium and made of a reaction product comprising a lithium titanate which has a spinnel structure and is represented by the general formula, Li x Ti y O₄, wherein 0.8≦x≦1.4 and 1.6≦y≦2.2, a separator separating the cathode and the anode from each other, and an electrolytic solution impregnated at least in the separator and containing a lithium salt dissolved in a non-aqueous solvent, wherein when subjected to X-ray diffraction analysis using a Cu target, said reaction product has diffraction peaks at least at 4.84 ± 0.02 angstroms, 2.53 ± 0.02 angstroms, 2.09 ± 0.02 angstroms and 1.48 ± 0.02 angstroms and a ratio of a peak intensity at 4.84 ± 0.02 angstroms and a peak intensity at 1.48 ± 0.02 angstroms of 100:30 ±10.
Claim 2
Dependent Claim
16 words
The cell according to Claim 1, wherein said reaction product consists essentially of said lithium titanate.
Claim 3
Dependent Claim
27 words
The cell according to Claim 1 or 2, wherein said lithium titanate consists essentially of LiTi₂O₄, Li 4/3 Ti 5/3 O₄ or Li 0.8 Ti 2.2 O₄.
Claim 4
Dependent Claim
34 words
The cell according to any of the preceding Claims, wherein said lithium salt in said electrolytic solution is a member selected from the group consisting of LiPF₆, LiCF₃SO₃, LiBF₄, LiClO₄, LiN(CF₃SO₂)₂ and mixtures thereof.
Claim 5
Dependent Claim
154 words
A rechargeable lithium cell which comprises: a cathode which has a discharge potential not less than 2 V relative to a Li/Li⁺ anode; an anode capable of doping and un-doping lithium and made of a reaction product which comprises mixed crystals of a lithium titanate which has a spinnel structure and is represented by the general formula, Li x Ti y O₄, wherein 0.8≦x≦1.4 and 1.6≦y≦2.2 and rutile-type titanium dioxide; a separator separating the cathode and the anode from each other; and an electrolytic solution impregnated at least in the separator and containing a lithium salt dissolved in a non-aqueous solvent, wherein when subjected to X-ray diffraction analysis using a Cu target, said reaction product has diffraction peaks at least at 4.84 ± 0.02 angstroms, 3.25 ± 0.02 angstroms, 2.53 ± 0.02 angstroms, 2.49 ± 0.02 angstroms, 2.19 ± 0.02 angstroms, 2.09 ± 0.02 angstroms, 1.69 ± 0.02 angstroms, and 1.48 ± 0.02 angstroms.
Claim 6
Dependent Claim
16 words
The cell according to Claim 5, wherein said reaction product consists essentially of said mixed crystals.
Claim 7
Dependent Claim
22 words
The cell according to Claim 5 or 6, wherein said lithium titanate and said rutile-type titanium oxide coexist in one mixed crystal.
Claim 8
Dependent Claim
77 words
The cell according to any of the preceding Claim 5 to 7, wherein said reaction product has a ratio of a peak intensity at 4.84 ± 0.02 angstroms and a peak intensity at 1.48 ± 0.02 angstroms of 100:30 ±10 and ratios of a peak intensity at 3.25 ± 0.02 angstroms, a peak intensity at 2.58 ± 0.02 angstroms and a peak intensity at 1.69 ± 0.02 angstroms of 100 : 50 ± 10 : 60 ±10.
Claim 9
Dependent Claim
24 words
The cell according to any of Claim 5 to 8, wherein said lithium titanate consists essentially of LiTi₂O₄ or Li 4/3 Ti 5/3 O₄.
Claim 10
Dependent Claim
30 words
The cell according to any of the Claim 5 to 9, wherein said lithium salt in said electrolytic solution is selected from LiPF₆, LiCF₃SO₃, LiBF₄, LiClO₄, LiN(CF₃SO₂)₂ and mixtures thereof.
Claim 11
Dependent Claim
142 words
A process for making an anode capable of doping and un-doping lithium in a rechargeable lithium cell of the type which comprises a cathode which has a discharge potential not less than 2 V relative to the anode, a separator separating the cathode and the anode from each other, and an electrolytic solution impregnated at least in the separator and containing a lithium salt dissolved in a non-aqueous solvent, which method comprising subjecting a lithium compound and anatase or rutile-type titanium dioxide to thermal treatment at an atomic ratio of Li/Ti in the lithium compound and anatase or rutile-type titanium dioxide of 0.8:1 to 1:3 under heating conditions sufficient to obtain a product comprising a lithium titanate compound having a spinnel structure and represented by the formula, Li 4/3 Ti 5/3 O₄, and forming the powder product to obtain an anode body.
Claim 12
Dependent Claim
16 words
The process according to Claim 11, wherein said lithium compound is lithium hydroxide or lithium carbonate.
Claim 13
Dependent Claim
22 words
The process according to Claim 11 or 2, wherein the thermal treatment is effected at a temperature of from 800°C to 950°C.
Claim 14
Dependent Claim
30 words
The process according to Claim 11, 12 or 13, wherein said crystal product consists essentially of said lithium titanate or mixed crystals of said lithium titanate and rutile-type titanium dioxide.
References Cited (Backward Citations)
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