1.5-3 V Lithium Batteries With Overcharge Protection

Abstract

Rechargeable, non-aqueous lithium batteries which contain, as active anode material, either lithium metal or a lithium alloy, an active cathode material with a redox potential in the range of between 1.5 and 3.4 V vs Li/Li.sup.+ and lithium rhodanide (LiSCN) as electrolyte component. One or more related methods for providing overcharge protection are also described herein.

Claims

1.-15. (canceled)

16. A method for providing overcharge protection, the method comprising: providing a rechargeable and non-aqueous lithium battery comprising an active anode material, an active cathode material having a redox potential in the range between about 1.5 and 3.4 V vs. Li/Li.sup.+, and an electrolyte comprising a redox shuttle compound; wherein the redox shuttle compound is present in an amount sufficient to oxidize reversibly at about 0.5 to 1.5 V above the redox potential of the active cathode material of the rechargeable and non-aqueous lithium battery.

17. The method of claim 16, wherein the redox shuttle compound is lithium rhodanide (LiSCN).

18. The method of claim 17, wherein the redox shuttle compound is present in the electrolyte in a concentration in the range of from 0.01 to 15 wt. %.

19. The method of claim 17, wherein the redox shuttle compound is present in the electrolyte in a concentration in the range of from 0.01 to 10 wt. %.

20. The method of claim 17, wherein the active anode material is selected from the group consisting of lithium metal and a lithium alloy.

21. The method of claim 19, wherein the active cathode material is selected from the group consisting of CF.sub.x, a transition metal oxide, a transition metal sulfide, a transition metal fluoride, a transition metal oxyfluoride, an organic redox-active compound, sulfur, and selenium.

22. The method of claim 17, wherein the electrolyte further comprises at least one additional conductive salt selected from the group consisting of LiPF.sub.6, a lithium fluoroalkyl phosphate, LiBF.sub.4, LiOSO.sub.2CF.sub.3, a methide salt, LiClO.sub.4, a lithium chelatoborate, a lithium fluorochelatoborate, a lithium chelatophosphate, a lithium fluorochelatophosphate and a lithium halide.

23. The method of claim 17, wherein the active anode material is a powder and present in a compacted form as the active anode material.

24. The method of claim 17, wherein the active cathode material is selected from the group consisting of CF.sub.x, MnO.sub.2, V.sub.2O.sub.5, V.sub.6O.sub.13, FcOF, FcF.sub.3, S, and FcF.sub.2.

25. The method of claim 17, wherein the electrolyte is in a liquid, gelatinous or solid state at room temperature.

26. The method of claim 17, wherein the electrolyte comprises organic aprotic solvents selected from the group consisting of a cyclic ether, an acyclic ether, a polyether, a nitrile, a lactone, a carbonic acid ester and an ionic liquid.

27. The method of claim 17, wherein the electrolyte comprises at least one organic aprotic solvent selected from the group consisting of tetrahydropyran, tetrahydrofuran, 1,2-dimethoxyethane, diethylene glycol dimethyl ether, acetonitrile, adiponitrile, malodinitrile, glutaronitrile, -butyrolactone and an imidazolium salt.

28. The method of claim 17, wherein the electrolyte further comprises at least one organic polymer selected from the group consisting of polyethylene oxide, polyacrylonitrile, polyvinylidene fluoride, and any combination of two or more of the foregoing.

29. The method of claim 21 further comprising: charging the rechargeable and non-aqueous lithium battery so as to cause the redox shuttle compound to oxidize reversibly at about 0.5 to 1.5 V above the redox potential of an active cathode material of the rechargeable and non-aqueous lithium battery.

30. A method for providing overcharge protection, the method comprising: providing a rechargeable and non-aqueous lithium battery comprising an active anode material selected from the group consisting of lithium metal and a lithium alloy, an active cathode material having a redox potential in the range between about 1.5 and 3.4 V vs. Li/Li.sup.+, and an electrolyte comprising a redox shuttle compound present in the electrolyte in a concentration in the range of from 0.01 to 10 wt. %; and charging the rechargeable and non-aqueous lithium battery so as to cause the redox shuttle compound to oxidize reversibly at about 0.5 to 1.5 V above the redox potential of an active cathode material of the rechargeable and non-aqueous lithium battery; wherein the redox shuttle compound is lithium rhodanide (LiSCN); and wherein the active cathode material is selected from the group consisting of CF.sub.x, MnO.sub.2, V.sub.2O.sub.5, V.sub.6O.sub.13, FeOF, FeF.sub.3, S, and FeF.sub.2.

31. The method of claim 30, wherein the electrolyte further comprises at least one additional conductive salt selected from the group consisting of LiPF.sub.6, a lithium fluoroalkyl phosphate, LiBF.sub.4, LiOSO2CF.sub.3, a methide salt, LiClO.sub.4, a lithium chelatoborate, a lithium fluorochelatoborate, a lithium chelatophosphate, a lithium fluorochelatophosphate, lithium halide, and any combination of two or more of the foregoing.

32. The method of claim 30, wherein the electrolyte further comprises at least one organic aprotic solvent selected from the group consisting of tetrahydropyran, tetrahydrofuran, 1,2-dimethoxyethane, diethylene glycol dimethyl ether, acetonitrile, adiponitrile, malodinitrile, glutaronitrile, -butyrolactone and an imidazolium salt.

33. A rechargeable and nonaqueous lithium battery comprising: an active anode material selected from the group consisting of lithium metal and a lithium alloy; an active cathode material having a redox potential in the range between 1.5 and 3.4 V vs. Li/Li.sup.+, the active cathode material selected from the group consisting of CF.sub.x, a transition metal oxide, a transition metal sulfide, a transition metal fluoride, a transition metal oxyfluoride, an organic redox-active compound, sulfur, and selenium; and an electrolyte consisting of a reversible redox shuttle compound that is present in the electrolyte in a concentration in the range of from 0.01 to 15 wt %, which is lithium rhodanide (LiSCN), at least one additional conductive salt, and at least one organic aprotic solvent, wherein the at least one additional conductive salt is selected from the group consisting of LiPF.sub.6, a lithium fluoroalkyl phosphate, LiBF.sub.4, LiOSO.sub.2CF.sub.3, a methide salt, LiClO.sub.4, a lithium chelatoborate, a lithium fluorochelatoborate, a lithium chelatophosphate, a lithium fluorochelatophosphate and a lithium halide.

Description

[0026] FIG. 1 shows a cyclovoltagram of an electrolyte with 0.1 M LiSCN in 1M LiPF.sub.6/EC:DMC (1:1 by weight) and a Pt electrode, recorded with a rate of advance of 100 mV/s in the scanning range of 3.0-4.0 V vs. Li/Li.sup.+.