Patent US694328A successfully refreshed from Google Patents.
Patent US4959282A successfully refreshed from Google Patents.
US4959282A
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Cathode active materials, methods of making same and electrochemical cells incorporating the same
Assignee: Moli Energy Ltd
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Filing: 1988-07-11
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Granted: 1990-09-25
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Expires: 2008-07-11
Abstract
Abstract Cathode-active material for electrochemial cells is prepared by reacting gamma phase MnO 2 with Li. The molar ratio of Li to MnO 2 is about 0.33 to about 0.43.
Inventors
- 👤 Jeffery R. Dahn
- 👤 Brian M. Way
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:15
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/36; H01M4/48; H01M4/50; H01M4/505; C; C01; C01G; C01G45/00; C01G45/02; C01G45/024; C01G45/12; C01G45/1221; C01G45/1228; H01M4/13; H01M4/131; H01M4/139; H01M4/1391; H01M4/485; C01P; C01P2002/00; C01P2002/50; C01P2002/52; C01P2002/54; C01P2002/70; C01P2002/74; C01P2006/00; C01P2006/40; H01M10/00; H01M10/05; H01M10/052; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
58 words
A method of making a cathode active material for an electrochemical cell comprising the steps of providing a substantially dry intermediate including a lithium-containing compound and gamma MnO 2 at a mean molar ratio of lithium to gamma MnO 2 of about 0.33 to about 0.43 and heat-treating said intermediate in a drying atmosphere above about 300° C.
Claim 2
Independent Claim
58 words
A method of making a cathode active material for an electrochemical cell comprising the steps of providing a substantially dry intermediate including a lithium-containing compound and gamma MnO 2 at a mean molar ratio of lithium to gamma MnO 2 of about 0.33 to about 0.43 and heat-treating said intermediate in a drying atmosphere above about 300° C.
Claim 3
Dependent Claim
22 words
A method as claimed in claim 1 wherein said gamma MnO 2 in said intermediate is porous MnO 2 in particulate form.
Claim 4
Dependent Claim
28 words
A method as claimed in claim 2 wherein said heat-treating step is conducted at between about 300° C. and about 450° C. for at least about 30 minutes.
Claim 5
Dependent Claim
26 words
A method as claimed in claim 3 wherein said heat-treating step is conducted at about 355° to about 385° C. for at least about one hour.
Claim 6
Dependent Claim
49 words
A method as claimed in claim 2 wherein said step of providing said intermediate includes the steps of contacting said particulate MnO 2 with a solution of said lithium-containing compound in a solvent and evaporating said solvent from said particulate MnO 2 while agitating said particulate MnO 2 .
Claim 7
Dependent Claim
30 words
A method as claimed in claim 5 wherein said said evaporation and agitation steps are continued at least until said particulate MnO 2 is substantially devoid of free liquid solvent.
Claim 8
Dependent Claim
25 words
A method as claimed in claim 6 wherein the dry intermediate material resulting from said evaporation step is transferred directly to said heat treating step.
Claim 9
Dependent Claim
14 words
A method as claimed in claim 6 wherein said solvent consists essentially of water.
Claim 10
Dependent Claim
26 words
A method as claimed in claim 8 wherein said lithium-containing compound is selected from the group consisting of LiOH, Li 2 O and LiNO 3 .
Claim 11
Dependent Claim
15 words
A method as claimed in claim 9 wherein said lithium-containing compound consists essentially of LiOH.
Claim 12
Dependent Claim
30 words
A method as claimed in claim 2 wherein said providing step is conducted so that the mean molar ratio of Li to MnO 2 is about 0.36 to about 0.40.
Claim 13
Dependent Claim
12 words
A cathode-active material made by a process as claimed in claim 1.
Claim 14
Dependent Claim
12 words
A cathode-active material made by a process as claimed in claim 6.
Claim 15
Dependent Claim
12 words
A cathode-active material made by a process as claimed in claim 10.
Claim 16
Dependent Claim
18 words
An electrochemical cell comprising a lithium-containing anode, an electrolyte and a cathode-active material as claimed in claim 12.
Claim 17
Dependent Claim
48 words
A cathode-active material made by a process as claimed in claim 1 having a stoichiometric formula Li y MnO 2 , wherein y is about 0.33 to about 0.43, at least a portion of said material being X-phase, the material having R 53/37 of at least about 0.6.
Claim 18
Dependent Claim
15 words
A cathode-active material according to claim 16 having R 53/37 of at least about 0.7.
Claim 19
Dependent Claim
13 words
A cathode-active material according to claim having R 45/37 less than about 0.15.
Claim 20
Dependent Claim
18 words
An electrochemical cell comprising a lithium anode, an electrolyte and a cathode-active material as claimed in claim 16.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-24 | 1994-03-26 | 1994-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-24 | 1998-03-26 | 1998-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-24 | 2002-03-26 | 2002-09-25 | $7700.00 | Window Closed / Lapsed |