Current collector for polymer electrochemical cells and eclectrochemical generators thereof
A current collector for an electrochemical cell. The current collector comprises a polymer support film having a surface. The current collector also comprises a conductive metallic layer on at least a portion of the surface of the polymer support film, the conductive metallic layer having a first thickness. The current collector further comprises a protective metallic layer on the conductive metallic layer. The protective metallic layer has a second thickness less than the first thickness and is adapted to protect the conductive metallic layer against corrosion. Also provided are a method of manufacturing such a current collector and an electrochemical generator comprising such a current collector.
1 . A current collector for an electrochemical cell, said current collector comprising:
a polymer support film having a surface;
a conductive metallic layer on at least a portion of the surface of said polymer support film, said conductive metallic layer having a first thickness; and
a protective metallic layer on said conductive metallic layer, said protective metallic layer having a second thickness less than the first thickness and being adapted to protect said conductive metallic layer against corrosion.
2 . A current collector as defined in claim 1 , wherein said polymer support film is selected from the group consisting of polystyrene, polyethylene terephthalate, polycarbonate, polypropylene, and polyamide.
3 . A current collector as defined in claim 1 , wherein said conductive metallic layer is selected from the group consisting of Al, Cd, Cu, Mg, Ni and Sn.
4 . A current collector as defined in claim 1 , wherein said protective metallic layer is selected from the group consisting of Ag, Pd, Pt, Sn and Cr.
5 . A current collector as defined in claim 1 , wherein said conductive metallic layer is coated onto said at least a portion of the surface of said polymer support film by metal vapor deposition.
6 . A current collector as defined in claim 1 , wherein said protective metallic layer is coated onto said conductive metallic layer by metal vapor deposition.
7 . A current collector as defined in claim 1 , wherein said protective metallic layer is a metal oxide layer.
8 . A current collector as defined in claim 1 , wherein said polymer support film is electronically conductive.
9 . A current collector as defined in claim 8 , wherein said polymer support film being electronically conductive comprises said polymer support film being doped with a sufficient amount of a conductive material so as to be electronically conductive.
10 . A current collector as defined in claim 9 , wherein said conductive material is selected from the group consisting of carbon powder, graphite, powdered nickel, and metal particles.
11 . A current collector as defined in claim 8 , wherein said polymer support film is a polymer having a conjugated network of double bonds.
12 . A current collector as defined in claim 1 , wherein the surface is a first surface, said conductive metallic layer is a first conductive metallic layer, and said protective metallic layer is a first protective metallic layer, said polymer support film having a second surface, said current collector further comprising:
a second conductive metallic layer on at least a portion of the second surface of said polymer support film, said second conductive metallic layer having a third thickness; and
a second protective metallic layer on said second conductive metallic layer, said second protective metallic layer having a fourth thickness less than the third thickness and being adapted to protect said second conductive metallic layer against corrosion.
13 . A current collector as defined in claim 1 , wherein the first thickness is less than about 3 microns.
14 . A current collector as defined in claim 13 , wherein the second thickness is between about 5 nanometers and about 500 nanometers.
15 . A current collector as defined in claim 14 , wherein said polymer support film has a third thickness, the third thickness being between about 1 micron and about 15 microns.
16 . A current collector as defined in claim 1 , wherein said conductive metallic layer is made of a first material and said protective metallic layer is made of a second material different from the first material.
17 . An electrochemical generator comprising at least one thin-film electrochemical cell, each one of said at least one thin-film electrochemical cell comprising:
at least one thin-film solid electrolyte disposed between a film constituting an anode and a film constituting a cathode; and
a current collector associated with one of said anode and said cathode, said current collector comprising:
a polymer support film having a surface;
a conductive metallic layer on at least a portion of the surface of said polymer support film, said conductive metallic layer having a first thickness; and
a protective metallic layer on said conductive metallic layer, said protective metallic layer having a second thickness less than the first thickness and being adapted to protect said conductive metallic layer against corrosion.
18 . An electrochemical generator as defined in claim 17 , wherein said at least one thin-film electrochemical cell comprises a plurality of thin-film electrochemical cells stacked together.
19 . An electrochemical generator as defined in claim 17 , wherein the surface is a first surface, said conductive metallic layer is a first conductive metallic layer, and said protective metallic layer is a first protective metallic layer, said polymer support film having a second surface, said current collector further comprising:
a second conductive metallic layer on at least a portion of the second surface of said polymer support film, said second conductive metallic layer having a third thickness; and
a second protective metallic layer on said second conductive metallic layer, said second protective metallic layer having a fourth thickness less than the third thickness and being adapted to protect said second conductive metallic layer against corrosion.
20 . An electrochemical generator as defined in claim 17 , wherein said conductive metallic layer is selected from the group consisting of Al, Cd, Cu, Mg, Ni and Sn.
21 . An electrochemical generator as defined in claim 17 , wherein said protective metallic layer is selected from the group consisting of Ag, Pd, Pt, Sn and Cr.
22 . An electrochemical generator as defined in claim 17 , wherein said conductive metallic layer is coated onto said at least a portion of the surface of said polymer support film by metal vapor deposition.
23 . An electrochemical generator as defined in claim 17 , wherein said protective metallic layer is coated onto said conductive metallic layer by metal vapor deposition.
24 . An electrochemical generator as defined in claim 17 , wherein said protective metallic layer is a metal oxide layer.
25 . An electrochemical generator as defined in claim 17 , wherein said polymer support film is electronically conductive.
26 . An electrochemical generator as defined in claim 25 , wherein said polymer support film being electronically conductive comprises said polymer support film being doped with a sufficient amount of a conductive material so as to be electronically conductive.
27 . An electrochemical generator as defined in claim 17 , wherein the first thickness is less than about 3 microns.
28 . An electrochemical generator as defined in claim 27 , wherein the second thickness is between about 5 nanometers and about 500 nanometers.
29 . An electrochemical generator as defined in claim 28 , wherein said polymer support film has a third thickness, the third thickness being between about 1 micron and about 15 microns.
30 . A method of manufacturing a current collector for an electrochemical cell, said method comprising:
providing a polymer support film having a surface;
coating a conductive metallic layer onto at least a portion of the surface of the polymer support film, the conductive metallic layer having a first thickness; and
coating a protective metallic layer onto the conductive metallic layer, the protective metallic layer having a second thickness less than the first thickness and being adapted to protect the conductive metallic layer against corrosion.
31 . A method as defined in claim 30 , wherein coating a conductive metallic layer onto at least a portion of the surface of the polymer support film comprises coating the conductive metallic layer onto the at least a portion of the surface of the polymer support film by metal vapor deposition.
32 . A method as defined in claim 30 , wherein coating a protective metallic layer onto the conductive metallic layer comprises coating the protective metallic layer onto the conductive metallic layer by metal vapor deposition.
33 . A method as defined in claim 30 , wherein the first thickness is less than about 3 microns.
34 . A method as defined in claim 33 , wherein the second thickness is between about 5 nanometers and about 500 nanometers.
35 . A method as defined in claim 34 , wherein the polymer support film has a third thickness, the third thickness being between about 1 micron and about 15 microns.