DRY ENERGY STORAGE DEVICE ELECTRODE AND METHODS OF MAKING THE SAME
An energy storage device can include a cathode and an anode, where at least one of the cathode and the anode are made of a polytetrafluoroethylene (PTFE) composite binder material including PTFE and at least one of polyvinylidene fluoride (PVDF), a PVDF co-polymer, and poly(ethylene oxide) (PEO). The energy storage device can be a lithium ion battery, a lithium ion capacitor, and/or any other lithium based energy storage device. The PTFE composite binder material can have a ratio of about 1:1 of PTFE to a non-PTFE component, such a PVDF, PVDF co-polymer and/or PEO.
1 . A cathode electrode film, comprising:
a material selected from an activated carbon, a conductive carbon and combinations thereof, and an active material selected from a lithium metal oxide, a lithium sulfide, or a combination thereof;
wherein the cathode electrode film comprises a composite binder material comprising polytetrafluoroethylene (PTFE) and at least one of polyvinylidene fluoride (PVDF), a PVDF co-polymer, and poly(ethylene oxide) (PEO), wherein the composite binder material comprises a mass ratio of 1:5 to 5:1 of the PTFE to the PVDF, the PTFE to the PVDF co-polymer, or the PTFE to the PEO; and
wherein the cathode electrode film is a self-supporting electrode film.
2 . The cathode electrode film of claim 1 , wherein the active material comprises a lithium metal oxide.
3 . The cathode electrode film of claim 1 , wherein the composite binder material comprises up to 90 weight % PTFE.
4 . The cathode electrode film of claim 1 , wherein the cathode electrode film comprises 5 weight % to 10 weight % of the composite binder material.
5 . The cathode electrode film of claim 1 , wherein the composite binder material comprises the PTFE and one of the PVDF, PVDF co-polymer or PEO.
6 . The cathode electrode film of claim 5 , wherein the composite binder material comprises a mass ratio of 1:1 to 5:1 of the PTFE to the PVDF, the PTFE to the PVDF co-polymer, or the PTFE to the PEO.
7 . The cathode electrode film of claim 6 , wherein the composite binder material comprises a mass ratio of 3:2 to 5:1 of the PTFE to the PVDF, the PTFE to the PVDF co-polymer, or the PTFE to the PEO.
8 . The cathode electrode film of claim 1 , wherein the composite binder material comprises a mass ratio of 1:1 to 3:1 of the PTFE to the PVDF, the PTFE to the PVDF co-polymer, or the PTFE to the PEO.
9 . The cathode electrode film of claim 1 , wherein the cathode electrode film comprises the activated carbon.
10 . The cathode electrode film of claim 9 , wherein the cathode electrode film comprises up to 10 weight % of the activated carbon.
11 . The cathode electrode film of claim 1 , wherein the cathode electrode film comprises the conductive carbon.
12 . The cathode electrode film of claim 1 , wherein the cathode electrode film is absent of solvent residue.
13 . The cathode electrode film of claim 1 , wherein the cathode electrode film comprises a binder matrix providing structural support to the cathode electrode film.
14 . An energy storage device comprising the cathode electrode film of claim 1 .
15 . The energy storage device of claim 14 , wherein the energy storage device further comprises an anode comprising an anode composite binder material comprising polytetrafluoroethylene (PTFE) and at least one of polyvinylidene fluoride (PVDF), a PVDF co-polymer, and poly(ethylene oxide) (PEO).
16 . The energy storage device of claim 15 , wherein the composite binder material of the cathode electrode film is different from the anode composite binder material.
17 . A method of fabricating a self-supporting cathode electrode film for use in an energy storage device, comprising:
combining a first portion of an activated carbon material, and at least one component of a composite binder material to form a first mixture, wherein the at least one component comprises at least one of polyvinylidene fluoride (PVDF), a PVDF co-polymer, and poly(ethylene oxide) (PEO);
subjecting the first mixture comprising the activated carbon material and the at least one component of the composite binder material to a high shear process;
adding a first portion of an active material selected from a lithium metal oxide, a lithium sulfide, or a combination thereof to form a second mixture;
adding polytetrafluoroethylene (PTFE) to the second mixture to form a third mixture, wherein a mass ratio of PTFE to the at least one component is 1:5 to 5:1; and
calendering the third mixture to form the self-supporting cathode electrode film;
wherein the method is a dry fabrication process in which no solvents are used.
18 . The method of claim 17 , wherein combining comprises combining the activated carbon material and the at least one component at a mass ratio of 1:5 to 5:1.
19 . The method of claim 18 , wherein combining comprises combining the activated carbon material and the at least one component at a mass ratio of 1:1 to 5:1.
20 . The method of claim 17 , wherein the mass ratio of PTFE to the at least one component is 3:2 to 5:1.
21 . The method of claim 17 , wherein the mass ratio of PTFE to the at least one component is 1:3 to 3:1.
22 . The method of claim 17 , wherein the at least one component comprises PVDF.
23 . The method of claim 17 , further comprising:
combining after the subjecting step a second portion of activated carbon material and a conductive carbon additive to form the second mixture.
24 . The method of claim 17 , wherein the high shear process comprises fibrillizing the PTFE.
25 . The method of claim 17 , wherein the high shear process comprises jet-milling.
26 . The method of claim 17 , wherein the active material comprises a lithium metal oxide.
27 . The method of claim 26 , wherein the active material comprises lithium nickel manganese cobalt oxide, lithium manganese oxide, lithium iron phosphate, lithium cobalt oxide, or lithium nickel cobalt aluminum oxide.