Composite element having a titanium chalcogenide or oxychalcogenide layer, more particularly usable as the positive electrode in a thin film electrochemical cell

• US 5,202,201 A
• Filed: 05/02/1991
• Issued: 04/13/1993
• Est. Priority Date: 11/04/1988
• Status: Expired due to Term

• Current Assignee: Centre National De La Recherche Scientifique
• Original Assignee: Centre National De La Recherche Scientifique
• Inventors: Meunier, Georges, Dormoy, Richard, Levasseur, Alain
• Primary Examiner(s): Niebling, John
• Assistant Examiner(s): Leader, William T.
• Application Number:
  US07/675,917
• Time in Patent Office: 712 Days
• Field of Search: 204/192.15, 204/192.17, 204/192.28, 204/192.29, 204/290 F, 429/162, 429/193, 429/218, 359/265, 359/267, 359/269, 359/270, 359/273, 428/689, 428/698, 428/701
• US Class Current: 429/322
• CPC Class Codes: C03C 3/127 containing TiO2 as glass former
• CPC Class Codes: C23C 14/0623 Sulfides, selenides or tellurides
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0562 Solid materials
• CPC Class Codes: H01M 4/58 of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 6/18 with solid electrolyte
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The invention relates to a composite element usable in an electrochemical generator. The element comprises a substrate (1) covered by cathodic sputtering with a layer (5) of amorphous material TiO_a X_B with X=S, Se or Te and

0.01<a≦2,

0.01<b≦3,

2≦a+b≦3.

The layer (5) consitutes the positive electrode of the generator and it can be associated with a lithium negative electrode (9) and a lithium ion conductive glass electrolyte (7).

Claims

1. Composite element constituted by a substrate coated by cathodic sputtering of a homogeneous, continuous, compact, thin layer of an isotropic, X-ray amorphous material in accordance with the formula:

space="preserve" listing-type="equation">TiO.sub.a X.sub.b

in which X represents a sulphur, selenium or tellurium atom and a and b are such that 0.01≦

a≦

2, 0.01≦

b≦

2 and 2≦

a+b≦

3, said coating having a thickness of 200 nm to 10 μ

m, an amorphous structure and a density lower than that of crystallized TiO₂ or TiS₂, without surface porosity.

2. Element according to claim 1, characterized in that X represents a sulphur atom.

3. Composite element according to any one of the claims 1 and 2, characterized in that the substrate is an insulating material covered by an electricity conducting material layer on which is deposited the TiO_a X_b material coating.

4. Electrochemical cell having a positive electrode, a negative electrode able to release an alkali metal ion or proton and an ionic conductive electrolyte positioned between the two electrodes, characterized in that the positive electrode is formed by a homogenous, continuous, composite, thin coating of isotropic, X-ray-amorphous material, deposited by cathodic sputtering and in accordance with the formula:

space="preserve" listing-type="equation">TiO.sub.a X.sub.b

in which X represents S, Se or Te, and a and b are such that 0.01≦

a≦

2, 0.01≦

b≦

2 and 2≦

a+b≦

3, said coating having a thickness of 200 nm to 10 μ

m, an amorphous structure and a density lower than that of crystallized TiO₂ or TiS₂, without surface porosity.

5. Electrochemical cell according to claim 4, characterized in that X represents S.

6. Electrochemical cell according to any one of the claims 4 and 5, characterized in that the negative electrode is of lithium.

7. Electrochemical cell according to claim 6, characterized in that the electrolyte is a lithium ion conductive glass.

8. Electrochemical cell according to claim 7, characterized in that the ionic conductive glass contains in variable proportions B₂ O₃, Li₂ O, Li_r X'"'"' with X'"'"' representing an anion of valency r.

9. Electrochemical cell according to any one of the claims 4 and 5, characterized in that the positive electrode is deposited on a substrate having a conductive layer forming a current collector.

10. Electrochemical cell according to claim 9, characterized in that the current collector is of platinum.

11. Electrochemical cell according to claim 9, characterized in that the current collector is of transparent conductive glass.