Patent US4581307A successfully refreshed from Google Patents.
US4581307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High specific energy electrochemical cell with low initial impedance
Assignee: SAFT Societe des Accumulateurs Fixes et de Traction SA
•
Filing: 1985-03-25
•
Granted: 1986-04-08
•
Expires: 2005-03-25
Abstract
Abstract A high specific energy electrochemical cell comprises: a negative active material (4) based on an alkali metal or on an alkaline-earth metal; a separator (8); a non-aqueous liquid electrolyte; and a positive electrode comprising a solid active mass (5). The positive mass is provided, on its electrolyte side, with a porous and electron conductive metal covering (12) which does not participate in the electrochemical reaction, whose thickness is of the order of a few microns, and which is in contact with the metal portions serving as a positive current collector. The covering greatly reduces the initial impedance of the cell.
Inventors
- 👤 Yves Jumel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:05
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/06; H01M6/00; H01M6/14; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
126 words
A high specific energy electrochemical cell including a negative active material selected from the group consisting of an alkali metal and an alkaline-earth metal, a positive electrode comprising a solid active mass, a separator disposed between the negative active material and the positive electrode, a non-aqueous liquid electrolyte contacting the negative active material and the positive electrode, and a positive current collector having metal portions, wherein the improvement comprises: the entire surface of said positive electrode exposed to the electrolyte being covered with a porous and electron conductive metal coating which does not participate in the electrochemical reaction, the thickness of the coating being of the order of a few microns, and the coating being in contact with the metal portions of the positive current collector.
Claim 2
Dependent Claim
126 words
A high specific energy electrochemical cell including a negative active material selected from the group consisting of an alkali metal and an alkaline-earth metal, a positive electrode comprising a solid active mass, a separator disposed between the negative active material and the positive electrode, a non-aqueous liquid electrolyte contacting the negative active material and the positive electrode, and a positive current collector having metal portions, wherein the improvement comprises: the entire surface of said positive electrode exposed to the electrolyte being covered with a porous and electron conductive metal coating which does not participate in the electrochemical reaction, the thickness of the coating being of the order of a few microns, and the coating being in contact with the metal portions of the positive current collector.
Claim 3
Dependent Claim
15 words
An electrochemical cell according to claim 1, wherein the coating is a vacuum-deposited metal layer.
Claim 4
Dependent Claim
30 words
An electrochemical cell according to claim 1, wherein the metal of said coating is chosen from the group consisting of lead, tin, gold, bismuth, zinc, cadmium, aluminum, and alloys thereof.
Claim 5
Dependent Claim
28 words
An electrochemical cell according to claim 1, wherein the positive electrode comprises an active material chosen from the group consisting of metal oxides, metal sulfides, and oxidized salts.
References Cited (Backward Citations)
US4268587A
Cited
GB2007903A
Cited
US4195123A
Cited
US4223078A
Cited
US4229509A
Cited
US4333994A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-07 | 1989-10-07 | 1990-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-07 | 1993-10-07 | 1994-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-07 | 1997-10-07 | 1998-04-08 | $7700.00 | Window Closed / Lapsed |