Solid polymer electrolytes

• US 6,645,675 B1
• Filed: 09/02/1999
• Issued: 11/11/2003
• Est. Priority Date: 09/02/1999
• Status: Expired due to Fees

• Current Assignee: Alfred J. Longhi Jr, Government of the United States of America
• Original Assignee: Lithium Werks Technology BV
• Inventors: Munshi, M. Zafar A.
• Primary Examiner(s): Gulakowski, Randy
• Assistant Examiner(s): Crepeau, Jonathan
• Application Number:
  US09/388,741
• Time in Patent Office: 1,531 Days
• Field of Search: 429/304-307, 429/309-314, 429/316, 429/317, 429/319-323, 429/188, 429/189, 429/233, 429/234, 429/162, 296/231, 296/235, 252/62.2
• US Class Current: 429/305
• CPC Class Codes: H01B 1/122 Ionic conductors
• CPC Class Codes: H01G 9/025 Solid electrolytes H01G11/54 takes precedence
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 10/0587 of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
• CPC Class Codes: H01M 4/04 Processes of manufacture in general
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/0421 involving vapour deposition
• CPC Class Codes: H01M 4/0426 Sputtering
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/667 in the form of layers, e.g. coatings
• CPC Class Codes: H01M 50/50 Current conducting connections for cells or batteries
• CPC Class Codes: H01M 6/10 with wound or folded electrodes
• CPC Class Codes: H01M 6/168 by additives
• CPC Class Codes: H01M 6/18 with solid electrolyte
• CPC Class Codes: H01M 6/181 with polymeric electrolytes
• CPC Class Codes: H01M 6/185 with oxides, hydroxides or oxysalts as solid electrolytes
• CPC Class Codes: H01M 6/188 Processes of manufacture
• CPC Class Codes: H01M 6/40 Printed batteries , e.g. thin film batteries
• CPC Class Codes: H01M 6/48 with bipolar electrodes
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/13 : Energy storage using capacitors
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49108 : Electric battery cell making
• CPC Class Codes: Y10T 29/49115 : including coating or impregnating

Abstract

A wide range of solid polymer electrolytes characterized by high ionic conductivity at room temperature, and below, are disclosed. These all-solid-state polymer electrolytes are suitable for use in electrochemical cells and batteries. A preferred polymer electrolyte is a cationic conductor which is flexible, dry, non-tacky, and lends itself to economical manufacture in very thin film form. Solid polymer electrolyte compositions which exhibit a conductivity of at least approximately 10⁻³-10⁻⁴ S/cm at 25° C. comprise a base polymer or polymer blend containing an electrically conductive polymer, a metal salt, a finely divided inorganic filler material, and a finely divided ion conductor. The new solid polymer electrolytes are combinable with various negative electrodes such as an alkali metal, alkaline earth metal, transition metal, ion-insertion polymers, ion-insertion inorganic electrodes, carbon insertion electrodes, tin oxide electrode, among others, and various positive electrodes such as ion-insertion polymers and ion-insertion inorganic electrodes to provide batteries and supercapacitors having high specific energy (Wh/kg) (gravimetric) and energy density (Wh/l) (volumetric), high cycle life, low self-discharge and providing improved safety.

Claims

1. A solid polymer electrolyte having a conductivity greater than 1×

10<sup>−

4</sup> S/cm at 25°

C. or below, absent any solvent, and comprising a mixture of;

a base polymer material comprising at least one ionically conductive polymer and having an initial conductivity of at least about 1×

10<sup>−

5</sup> S/cm at 25°

C. when combined with a metal salt in the absence of solvent;

a metal salt;

an inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g; and

an ionic conducting material having an average particle size less than 0.1 micron in diameter and an initial ionic conductivity of at least 2×

10<sup>−

3</sup> S/cm at 25°

C., wherein the solid polymer electrolyte does not contain a solvent.

2. The solid polymer electrolyte of claim 1 wherein said electrolyte is a cationic conductor.

3. The solid polymer electrolyte of claim 1 wherein said metal salt is a salt of an element chosen from the group consisting of sodium, lithium, potassium, magnesium and calcium.

4. The solid polymer electrolyte of claim 1 wherein said metal salt is a lithium salt.

5. The solid polymer electrolyte of claim 3 wherein said lithium salt is chosen from the group consisting of lithium hexafluorophosphate (LiPF₆), lithium perchlorate (LiClO₄), lithium tetrafluoroborate (LiBF₄), lithium hexafluoroarsenate (LiAsF₆), lithium tetrachloroaluminate (LiAlCl₄), lithium trifluoromethanesulfonate (LiCF₃SO₃), lithium methide (LiC(SO₂CF₃)₃ and lithium bis(trifluoromethane sulfonyl)imide (LiN(CF₃SO₂)₂).

6. The solid polymer electrolyte of claim 3 wherein said lithium salt is a plasticizer salt.

7. The solid polymer electrolyte of claim 1 comprising:

approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material;

approximately 1 to 25% (by weight of solid polymer electrolyte) metal salt;

approximately 0.1-60% (by volume of solid polymer electrolyte) inorganic filler; and

approximately 0.1-80% (by volume of solid polymer electrolyte) ionic conducting material.

8. The solid polymer electrolyte of claim 7 wherein the concentration of said inorganic filler is approximately 0.1-20% (by volume of solid polymer electrolyte) and the concentration of said ionic conducting material is approximately 0.1-20% (by volume of solid polymer electrolyte).

9. The solid polymer electrolyte of claim 1 wherein

said metal salt is a plasticizer lithium salt,

said inorganic filler is chosen from the group consisting of fumed silica and alumina, and

said ion conducting material is chosen from the group consisting of glassy lithium ion conductors and ceramic lithium ion conductors.

10. The solid polymer electrolyte of claim 9 wherein said lithium ion conducting material is chosen from the group consisting of sulfide glasses, lithium beta alumina, lithium silicates, lithium phosphorus oxynitride (Li₃PO₄), and other phosphate glasses.

11. The solid polymer electrolyte of claim 1 wherein said base polymer material comprises at least two polymers, the first said polymer being an ionically conductive polymer, the monomers of which have a hetero atom with a lone pair of electrons available for the metal ions of a metal salt to attach to and move between during conduction, when said first polymer is mixed with a metal salt.

12. The solid polymer electrolyte of claim 11 wherein said first polymer is chosen from the group consisting of linear polymers, random copolymers, block copolymers, comb-branched block copolymers, network structures, single ion conductors, polyvinylidene fluoride or chloride and copolymers thereof, poly(chlorotrifluoroethylene), poly(ethylene-chlorotrifluoroethylene), and poly(fluorinated ethylene-propylene).

13. The solid polymer electrolyte of claim 11 wherein said first polymer is chosen from the group consisting of polyethylene oxide (PEO), oxymethylene linked PEO, PEO-PPO-PEO crosslinked with trifunctional urethane;

poly(bis-methoxy-ethoxy-ethoxide))-phosphazene (MEEP);

a trihydroxy linked PEO crosslinked with difunctional urethane, poly((oligo)oxyethylene)methacrylate-co-alkali metal methacrylate;

polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), polymethylacrylonitrile (PAN);

polysiloxanes and their copolymers, polyvinylidene fluoride or chloride and copolymers thereof, poly(chlorotrifluoro-ethylene), poly(ethylene-chlorotrifluoroethylene), poly(fluorinated ethylene-propylene), acrylate-based polymer, combinations of the foregoing polymers either condensed or crosslinked to form a different polymer, and physical mixtures of any of the foregoing polymers,

provided said first polymer is combinable with a lithium salt such that the ionic conductivity of said first polymer is enhanced.

14. The solid polymer electrolyte of claim 11 wherein the second of said at least two polymers is more inert with respect to ionic conductivity and is mechanically stronger than said first polymer when each said polymer is in the form of a thin film.

15. The solid polymer electrolyte of claim 14 wherein said second polymer is chosen from the group consisting of polyester (PET), polypropylene (PP), polyethylene napthalate (PEN), polyvinylidene fluoride (PVDF), polycarbonate (PC), polyphenylene sulfide (PPS), and polytetrafluoroethylene (PTFE).

16. The solid polymer electrolyte of claim 1 wherein the composition of said base polymer material comprises approximately 1% to 99% (by weight of said base polymer material) of one polymer and the remainder of said base polymer material comprises at least one other polymer.

17. The solid polymer electrolyte of claim 1 wherein said base polymer material is dimensionally stable up to at least 150°

C. in said solid polymer electrolyte.

18. The solid polymer electrolyte of claim 1 wherein said at least one of said at least one polymer has a non-linear molecular structure and said solid polymer electrolyte further comprises a resilient, amorphous structure.

19. The solid polymer electrolyte of claim 1 wherein said electrolyte is in the form of a 0.2 to 100 micron thick film.

20. The solid polymer electrolyte of claim 19 wherein said electrolyte is in the form of a 0.2 to 10 micron thick film.

21. The solid polymer electrolyte of claim 20 wherein said electrolyte is in the form of a 0.2 to 3 micron thick film.

22. The solid polymer electrolyte of claim 1 further characterized by a resistance of no more than approximately 1 Ω

/cm² when employed as a thin-film electrolyte in an electrochemical cell.

64. In a thin lithium polymer electrolyte rechargeable battery including an anode, a cathode and a polymer electrolyte, the improvement comprising:

substituting for said anode an ultra thin film metallized polymer substrate having a thickness of approximately 0.5 to 50 microns and a lithium metal layer approximately 0.1 to 100 microns thick overlying a metallized layer of said metallized polymer substrate;

substituting for said cathode an ultra thin film metallized polymer substrate having a thickness of approximately 0.5 to 50 microns and an active cathode material layer approximately 0.1-100 microns thick overlying a metallized layer of said metallized polymer substrate; and

substituting for said polymer electrolyte the thin film solid polymer electrolyte of claim 4.

65. The battery of claim 64 wherein substituting for said anode and said cathode include using metallized polymer substrates having metallization layers up to 1 micron thick.

66. The battery of claim 65 wherein substituting for said anode and said cathode includes using metallized polymer substrates having metallization layers approximately 0.01 micron thick.

67. A thin electrode for a lithium polymer electrolyte battery comprising:

an ultra-thin film metal substrate for at least one electrode substrate of a lithium polymer electrolyte battery, said ultra-thin film metal substrate having a thickness of approximately 1 to 10 microns;

a layer of active electrode material overlying a side of said metal substrate; and

a layer of the solid polymer electrolyte according to claim 4 overlying said active electrode material.

68. A thin electrode for a lithium polymer electrolyte battery comprising:

an ultra-thin film metallized polymer substrate for at least one electrode substrate of a lithium polymer electrolyte battery, said ultra-thin film metalized polymer substrate having a thickness of approximately 1 to 10 microns and comprising a polymer layer and a first metallization layer having a conductivity of approximately 0.01-1.0 ohm per square, said first metallization layer adhering to a first side of said polymer layer;

a layer of active electrode material overlying said first metallization layer; and

a layer of the solid polymer electrolyte according to claim 4 overlying said active electrode material.

69. The electrode of claim 68 wherein said first side of said polymer layer comprises a first non-metallized margin.

70. The electrode of claim 69 wherein said first non-metallized margin extends approximately 1 to 3 mm from an edge of said first side to a edge of said first metallization layer.

71. The electrode of claim 70 further comprising a second metallization layer adhered to a second side of said polymer layer, said second side of said polymer layer comprising a second non-metallized margin extending approximately 1 to 3 mm from said edge to an edge of said second metallization layer.

72. The electrode of claim 71 further comprising a layer of another active electrode material overlying said second metallized layer.

73. A solid state laminar electrochemical cell comprising:

an anode layer;

a cathode layer;

a layer of solid polymer electrolyte according to claim 1 disposed between said anode and cathode layers;

an anode current collector attached to said anode; and

a cathode current collector attached to said cathode.

74. The solid state laminar electrochemical cell of claim 73 wherein each said current collector is a very thin material chosen from the group consisting of metallic elements less than 10μ

thick and metallized plastics 0.5 to 50μ

thick.

75. An orientation tolerant polymer electrolyte battery having an all-solid-state composition comprising the laminar electrochemical cell of claim 73.

83. In a polymer electrolyte battery containing at least one polymer electrolyte layer, the improvement comprising the solid state polymer electrolyte of claim 1 substituted for said at least one polymer electrolyte layer, said improvement providing a cell resistance less than or equal to that of a corresponding liquid electrolyte-containing lithium battery.

84. In a rechargeable lithium polymer electrolyte battery containing at least one polymer electrolyte layer, the improvement comprising an overcharge resistant solid state polymer electrolyte of claim 4 substituted for said at least one polymer electrolyte layer, said improvement providing a cell resistance less than or equal to that of a corresponding liquid electrolyte-containing lithium battery.

85. The improved lithium polymer battery of claim 84 wherein said battery further comprises current collectors and the improvement further comprising ultra-thin current collectors chosen from the group consisting of metallic elements less than 10μ

thick and metallized plastics 0.5 to 50μ

thick substituted for said current collectors.

86. In a thin lithium polymer electrolyte rechargeable battery comprising a pair of spaced-apart electrodes, each said electrode comprising a polymer substrate having an adherent electrically conductive layer disposed thereon, and a polymeric electrolyte disposed between said pair of electrodes, the improvement comprising substituting for said at least one electrode a flexible ultra thin film metallized polymer substrate having a polymer layer approximately 0.5-50 microns thick, a metal layer up to approximately 0.01 micron thick, and a layer of active material up to approximately 5 microns thick, and substituting for said polymeric electrolyte the solid polymer electrolyte of claim 9 in the form of a thin film up to approximately 5 microns thick.

23. A chemically stable solid polymer electrolyte for use with a lithium metal anode of a polymer electrolyte battery, said electrolyte comprising:

approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material comprising at least one ionically conductive polymer and having an initial conductivity of at least approximately 10<sup>−

5</sup> S/cm at 25°

C. when combined with a lithium salt in the absence of solvent,

approximately 1 to 25% (by weight of the solid polymer electrolyte) lithium salt,

approximately 0.1-60% (by volume of the solid polymer electrolyte) inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g,

approximately 0.1-80% (by volume of the solid polymer electrolyte) lithium ion conducting material having an average particle size less than 0.1 micron in diameter and an initial ionic conductivity of at least 2×

10<sup>−

3</sup> S/cm at 25°

C., wherein the solid polymer electrolyte does not contain a solvent.

24. A method of making a solid polymer electrolyte having a conductivity greater than 1×

10<sup>−

4</sup> S/cm at 25°

C. in the absence of solvent, the method comprising;

mixing together

a base polymer material comprising at least one ionically conductive polymer and having an initial conductivity of at least approximately 1×

10<sup>−

5</sup> S/cm at 25”

C. when combined with a metal salt in the absence of solvent,

a metal salt,

an inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g,

an ion conducting material having an average particle size less than 0.1 micron in diameter and an initial ionic conductivity of at least 2×

10<sup>−

3</sup> S/cm at 25°

C.,

optionally, a liquid organic solvent, and

optionally, a curing agent, to form a mixture;

optionally, maintaining the temperature of said mixture at the melting point of said base polymer material;

forming said mixture into a solid polymer electrolyte;

evaporating said liquid organic solvent, if an organic solvent is present, and

optionally, curing said solid polymer electrolyte, such that a solvent-free solid polymer electrolyte is produced.

25. The method of claim 24 wherein said step of forming said mixture into a solid polymer electrolyte comprises forming a 0.2 to 100 microns thick solid polymer electrolyte film.

26. The method of claim 25 wherein said step of forming said mixture into a solid polymer electrolyte comprises forming a 0.2 to 10 microns thick solid polymer electrolyte film.

27. The method of claim 26 wherein said step of forming said mixture into a solid polymer electrolyte comprises forming a 0.2 to 3 microns thick solid polymer electrolyte film.

28. The method of claim 24 further comprising:

preparing a polymer/salt intermediate composition containing said base polymer material and said metal salt;

forming an aliquot of said intermediate composition into an initial polymer/salt electrolyte; and

determining a conductivity of at least 5×

10<sup>−

5</sup> S/cm at 25°

C. for said initial polymer/salt electrolyte in the absence of solvent.

29. The method of claim 24 further comprising:

preparing a polymer/salt/filler intermediate containing;

said polymer/salt intermediate composition and an inorganic filler having an average particle size less than 0.5 micron in diameter and a surface area of at least approximately 100 m²/g;

forming an aliquot of said polymer/salt/filler intermediate into a solid; and

determining a conductivity of at least 1×

10<sup>−

4</sup> S/cm at 25°

C. for said polymer/salt/filler intermediate in the absence of solvent.

30. The method of claim 24 wherein said step of forming said mixture into a solid polymer electrolyte comprises stamping said mixture onto a substrate.

31. The method of claim 24 wherein said mixing step includes adding a liquid organic solvent and said method further comprises evaporating said liquid organic solvent prior to said optional step of curing said solid polymer electrolyte.

32. The method of claim 31 wherein said step of forming said mixture into a solid polymer electrolyte comprises casting said mixture using an apparatus chosen from the group consisting of knife coaters, doctor blade coaters, wire-wound bar coaters, air knife coaters, squeeze roll, gravure coaters, reverse roll coaters, cast film coaters and transfer roll coaters.

33. The method of claim 32 wherein said step of forming said mixture into a solid polymer electrolyte further comprises forming a final solid polymer electrolyte 0.2 to 100 microns thick.

34. The method of claim 24 wherein said mixing step comprises:

mixing together

approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material comprising at least one ionically conductive polymer and having an initial conductivity of at least approximately 10<sup>−

5</sup> S/cm at 25°

C. when combined with a metal salt in the absence of solvent,

approximately 1 to 25% (by weight of the solid polymer electrolyte) metal salt,

approximately 0.1-60% (by volume of the solid polymer electrolyte) inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g,

approximately 0.1-80% (by volume of the solid polymer electrolyte) ion conducting material having an average particle size less than 0.1 micron in diameter and an initial ionic conductivity of at least 2×

10<sup>−

3</sup> S/cm at 25°

C.,

optionally, a liquid organic solvent, and

optionally, a curing agent, to form a mixture.

35. The method of claim 34 wherein said mixing step further comprises maintaining the temperature of the mixture at the melting point of said base polymer material and said forming step includes forming said solid polymer electrolyte by a process chosen from the group consisting of hot-melt resin casting, hot-melt resin extrusion, hot-pressing, and hot-isostatic pressing said mixture.

36. The method of claim 35 wherein said forming step comprises hot-melt resin casting said mixture.

37. The method of claim 36 wherein said forming step further comprises achieving a final film thickness of approximately 2 to 4 microns.

38. The method of claim 35 wherein said forming step further comprises achieving a final film width of approximately 20 to 30 inches.

39. The method of claim 34 wherein said forming step comprises hot-melt resin extrusion of said mixture.

40. The method of claim 39 wherein said forming step further comprises achieving a final film thickness of approximately 2 to 25 microns.

41. A polymer electrolyte membrane characterized by a non-tacky consistency and a pin-hole free structure, said membrane containing no liquid organic solvent and prepared by the process of claim 39.

42. The polymer electrolyte membrane of claim 41 wherein said metal salt is a plasticizer salt and said membrane is flexible.

43. The polymer electrolyte membrane of claim 42 were in said membrane is conformable.

44. The method of claim 34 wherein said forming step comprises hot-pressing of said mixture.

45. The method of claim 34 wherein said forming step comprises hot-isostatic pressing of said mixture.

46. The method of claim 34 wherein said step of forming said mixture into a solid polymer electrolyte comprises extruding said mixture, and said mixing step includes blending said inorganic filler with the other said ingredients during extrusion of said mixture.

47. The method of claim 46 wherein said mixing step includes selecting an inorganic filler from the group consisting of fumed silica and alumina.

48. The method of claim 24 wherein said mixing step comprises:

mixing together

approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material comprising at least one ionically conductive polymer and having an initial conductivity of at least approximately 10<sup>−

5</sup> S/cm at 25°

C. when combined with a metal salt in the absence of solvent,

approximately 1 to 25% (by weight of solid polymer electrolyte) metal salt,

approximately 0.1-60% (by volume of solid polymer electrolyte) inorganic filler having an average particle size less than or equal to 0.01 micron in diameter and a surface area of at least approximately 100 m²/g,

approximately 0.1-80% (by volume of solid polymer electrolyte) ionic conducting material having an average particle size loss than 0.1 micron in diameter and an initial ionic conductivity of at least 2×

10<sup>−

3</sup> S/cm at 25°

C.,

optionally, a liquid organic solvent, and

optionally, a curing agent, to form a mixture.

49. The method of claim 48 wherein said mixing step includes dissolving said base polymer material and said metal salt in an anhydrous organic solvent.

50. The method of claim 48 wherein said step of forming a solid polymer electrolyte comprises casting said mixture on an inert substrate and evaporating said solvent.

51. The method of claim 48 wherein said step of forming said mixture into a solid polymer electrolyte comprises forming a solid polymer electrolyte ranging in thickness from approximately 0.5 to 100 microns.

52. The method of claim 48 comprising curing said solid polymer electrolyte after removing said solvent, if any.

53. The method of claim 52 wherein said curing step comprises applying ultraviolet or electron beam radiation to said solid polymer electrode.

54. The method of claim 24 wherein said mixing step comprises:

mixing together

approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material comprising at least one ionically conductive polymer and having an initial conductivity of at least approximately 10<sup>−

5</sup> S/cm at 25°

C. when combined with a lithium salt in the absence of solvent,

approximately 1 to 25% (by weight of solid polymer electrolyte) of a lithium salt,

approximately 0.1-20% (by volume of solid polymer electrolyte) inorganic filler having an average particle size less than or equal to 0.01 micron in diameter and a surface area of at least approximately 100 m²/g,

approximately 0.1-80% (by volume of solid polymer electrolyte) lithium ion conducting material chosen from the group consisting of sulfide glass and ceramic lithium ion conductors, and having an average particle size less than 0.1 micron in diameter and an initial ionic conductivity of at least 2×

10<sup>−

3</sup> S/cm at 25°

C.,

optionally, a liquid organic solvent, and

optionally, a curing agent, to form a mixture.

55. A method of making a solid polymer electrolyte for a lithium polymer electrolyte battery, the method comprising:

mixing together

approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material comprising at least one ionically conductive polymer and having an initial conductivity of at least approximately 1×

10<sup>−

5</sup> S/cm at 25°

C. when combined with a plasticizer lithium salt in the absence of solvent;

approximately 1 to 25% (by weight of solid polymer electrolyte) plasticizer lithium salt;

approximately 0.1-60% (by volume of solid polymer electrolyte) of an inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g;

approximately 0.1-80% (by volume of solid polymer electrolyte) an ion conducting material chosen from the group consisting of glassy conductors and ceramic lithium ion conductors; and

an anhydrous organic solvent, to form a base polymer/salt/inorganic filler/ionic conductor mixture; and

forming said mixture into a solvent free lithium solid polymer electrolyte having a conductivity of at least 10<sup>−

4</sup> to 10<sup>−

3</sup> S/cm at 25°

C. or below in the absence of solvent.

56. The method of claim 55 further comprising

casting said mixture into a sheet film; and

evaporating said organic solvent to yield a solid polymer electrolyte less than 1 micron thick.

57. The method of claim 55 further comprising

spraying said mixture onto a substrate, evaporating said solvent, and curing said polymer electrolyte, if said base polymer material comprises a curable polymer.

58. The method of claim 57 wherein said spraying comprises atomizing said mixture onto a substrate whereby a final polymer electrolyte film approximately 0.2 to 100 micron thick is formed.

59. A method of making a solid polymer electrolyte for a lithium polymer electrolyte battery, the method comprising:

mixing

(a) approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material, having a conductivity of at least approximately 5×

10<sup>−

5</sup> S/cm at 25°

C. when combined with a metal salt in the absence of solvent, said base polymer material comprising at least two polymers, the first said polymer being an ionically conductive polymer, the monomers of which have a hetero atom with a lone pair of electrons available for the metal ions of a metal salt to attach to and move between during conduction, when said first polymer is mixed with a metal salt, and the second of said at least two polymers being more inert with respect to ionic conductivity when combined with said metal salt and having greater mechanical strength than said first polymer when each said polymer is in the form of a thin film,

(b) approximately 1 to 25% (by weight of solid polymer electrolyte) plasticizer lithium salt,

(c) approximately 0.1-60% (by volume of solid polymer electrolyte) of an inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g, and

(d) approximately 0.1-80% (by volume of solid polymer electrolyte) ion conducting material chosen from the group consisting of glassy conductors and ceramic lithium ion conductors, to form a base polymer/salt/inorganic filler/ion conductor mixture; and

casting or extruding said mixture to yield a solvent-free solid polymer electrolyte in the form of a film having a conductivity greater than 1×

10<sup>−

4</sup> S/cm at 25°

C. or below in the absence of solvent.

60. The method of claim 59 further comprising maintaining the temperature of said mixture at the melting point of said base polymer material.

61. The method of claim 59 wherein said mixing step is modified by substituting approximately 0.1-20% (by volume of solid-polymer electrolyte) inorganic filler chosen from the group consisting of fumed silica and alumina, having an average particle size less than 0.01 micron in diameter and a surface area of at least approximately 100 m²/g for said approximately 0.1-60% inorganic filler;

and substituting approximately 0.1-20% (by volume of solid polymer electrolyte) ion conducting material chosen from the group consisting of glassy conductors and ceramic lithium ion conductors having an average particle size less than or equal to 0.01 micron in diameter, to form a base polymer/salt/inorganic filer/ionic conductor mixture for said 0.1-80% ion conducting material.

63. An automated spray coating process for manufacturing a thin film solid polymer electrolyte comprising:

the method of claim 59 wherein said step of spraying said mixture onto a substrate is modified by substituting the following step;

spraying said mixture onto a mechanically operated high speed moving substrate, evaporating said solvent, and optionally curing said polymer electrolyte.

62. An automated resin melt-cast process for manufacturing a thin film solid polymer electrolyte comprising:

mixing approximately 30 to 95% (by weight of solid polymer electrolyte) base polymer material comprising at least two polymers, the first said polymer chosen from the group consisting of polyethylene oxide (PEO), oxymethylene linked PEO, PEO-PPO-PEO crosslinked with trifunctional urethane, poly(bis(methoxy-ethoxy-ethoxide))-phosphazene (MEEP, a triol-type PEO crosslinked with difunctional urethane, poly((oligo)oxyethylene)methacrylate-co-alkali metal methacrylate, polyacrylonitrile (PMAN), polymethylmethacrylate (PMMA), polymethylacrylonitrile (PMAN), polysiloxanes and copolymers thereof, polyvinylidene fluoride or chloride and copolymers thereof, poly(chlorotrifluoro-ethylene), poly(ethylene-chlorotrifluoroethylene), poly(fluorinated ethylene-propylene), acrylate-based polymers, and combinations of the foregoing polymers either condensed or crosslinked to form a different polymer, and physical mixtures of any of the foregoing polymers, provided said first polymer is combinable with a lithium salt such that the ionic conductivity of said first polymer is enhanced; and

wherein said second polymer is chosen from the group consisting of polyester (PET), polypropylene (PP), polyethylene napthalate (PEN), polyvinylidene fluoride (PVDF), polycarbonate (PC), polyphenylene sulfide (PPS), and polytetrafluoroethylene (PTFE),

approximately 1 to 25% (by weight of solid polymer electrolyte) plasticizer lithium salt,

approximately 0.1-60% (by volume of solid polymer electrolyte) of an inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g, and

approximately 0.1-80% (by weight of solid polymer electrolyte) ion conducting material chosen from the group consisting of glassy conductors and ceramic lithium ion conductors, to form a base polymer/salt/inorganic filler/ionic conductor mixture;

while maintaining the temperature of said mixture at the melting temperature of said base polymer material, mechanically extruding said mixture onto a chilling wheel to yield a melt-cast film;

mechanically pulling said melt-cast film such that said melt-cast film is stretched to a final film thickness of approximately 4 microns or less to yield a solvent-free sheet film solid polymer electrolyte having a conductivity of at least 10<sup>−

4</sup> to 10<sup>−

3</sup> S/cm at 25°

C. or below when combined with a plasticizer lithium salt in the absence of solvent.

76. A thin film lithium polymer electrolyte battery comprising:

a resilient flexible hybrid polymeric electrolyte thin film having a conductivity of at least approximately 1×

10<sup>−

4</sup> S/cm and containing

a homogeneous blend of at least two polymers, one of which being an ionically conductive polymer having an initial conductivity of at least approximately 1×

10<sup>−

5</sup> S/cm at 25°

C. when combined with a lithium salt in the absence of solvent,

a lithium salt,

an inorganic filler having an average particle size less than 0.05 micron in diameter and a surface area of at least approximately 100 m²/g, and

a lithium ion conducting material having an average particle size less than 0.1 micron in diameter and an initial ionic conductivity of at least 2×

10<sup>−

3</sup> S/cm at 25°

C., wherein said polymeric electrolyte thin film does not contain a solvent; and

a pair of spaced-apart flexible thin film electrodes, each said electrode comprising a polymer substrate having an adherent electrically conductive layer disposed thereon, said polymeric electrolyte being tightly disposed between said pair of electrodes.

77. The battery of claim 76 wherein said polymer substrate of each said electrode comprises a polymer material selected from the group of polymers consisting of PET, PP, PPS, PEN, PVDF and PE.

78. The battery of claim 77 wherein each said polymer substrate is a metallized polymer substrate having a thin metal layer as said adherent electrically conductive layer.

79. The battery of claim 78 wherein each said metallized polymer substrate is approximately 0.5 to 50 microns thick and said thin metal layer has a resistivity of approximately 0.01 to 1 ohm per square.

80. The battery of claim 79 wherein said metallized polymer substrate further comprises a first side containing a first non-metallized margin.

81. The battery of claim 80 wherein said non-metallized margin extends approximately 1 to 3 mm from an edge of said first side to an edge of said first metallization layer.

82. The battery of claim 81 further comprising a second metallization layer adhered to a second side of said polymer layer, said second side of said polymer layer comprising a second unmetallized margin extending approximately 1 to 3 mm from said edge to an edge of said second metallization layer.