High performance lithium or lithium ion cell
Disclosed herein are lithium or lithium-ion batteries that employ an aluminum or aluminum alloy current collector protected by conductive coating in combination with electrolyte containing aluminum corrosion inhibitor and a fluorinated lithium imide or methide electrolyte which exhibit surprisingly long cycle life at high temperature.
1. A lithium-ion electrochemical cell, the cell comprising:
(i) an anode, the anode comprising an anode active material in electronically conductive contact with an anode current collector, wherein the anode active material is selected from the group consisting of lithium metal, carbon, lithium-intercalated carbon, lithium nitrides, lithium alloys, and lithium-alloy-forming compounds of tin, silicon, antimony, aluminum or titanium oxide;
(ii) a cathode exhibiting an upper charging voltage in the range of 3 to 5 volts with respect to a Li/Li + reference electrode, the cathode comprising:
a cathode current collector comprising:
aluminum or an aluminum alloy; and
a porous coating, the porous coating comprising a mixture of conductive carbon and graphite, wherein the coating is a composite further comprising a polymer;
wherein the porous coating has a practical thickness of 0.1 to 8micrometers; wherein the porous coating has a topography of variable peaks and valleys; wherein at least some valleys expose an aluminum or aluminum alloy surface; and
a film on the exposed aluminum or aluminum alloy surfaces; and
a cathode active material placed on top of the porous coating, the cathode active material comprising a lithium insertion transition metal oxide or phosphate;
(iii) an ion-permeable membrane as a separator between the anode and cathode; and
(iv) an electrolyte solution being in ionically conductive contact with the anode and cathode, the electrolyte solution comprising (a) an additive, (b) a lithium compound, and (c) at least one aprotic polar-solvent, a polymer, or a mixture of at least one aprotic polar solvent and a polymer;
the lithium compound being at a concentration from about 0.1 to 3 molar, wherein the lithium compound is C 2 F 5 SO 2 N − (Li + )SO 2 C 2 F 5 or FSO 2 N − (Li + )SO 2 F; and
the additive providing corrosion protection of the cathode current collector, the anode current collector, or both current collectors; wherein the additive is selected from the group consisting of LiBOB, LiF, LiFOB, LiPF 6 , LiBF 4 , LiAsF 6 , LiClO 4 , and LiPF n (R f ) m ; wherein n+m is 6, and R f is CF 3 or C 2 F 5 ; and wherein the additive creates the film on the exposed aluminum or aluminum alloy surfaces of the cathode current collector.
2. The electrochemical cell of claim 1 , wherein the lithium compound is C 2 F 5 SO 2 N − (Li + )SO 2 C 2 F 5 .
3. The electrochemical cell of claim 1 , wherein the cathode current collector comprises an aluminum alloy.
4. The electrochemical cell of claim 1 , wherein the additive providing corrosion protection is LiBOB.
5. The electrochemical cell of claim 1 , wherein the additive providing corrosion protection is a mixture of LiBOB and LiPF 6 .
6. The electrochemical cell of claim 1 , wherein the coating comprises conductive carbon.
7. The electrochemical cell of claim 1 , wherein the lithium compound is FSO 2 N − (Li + )SO 2 F.
8. The electrochemical cell of claim 1 , wherein the anode active material comprises carbon, and wherein the carbon is selected from the group consisting of graphite microbeads, natural graphites, artificial graphites, carbon fibers, and graphitic flakes.
9. The electrochemical cell of claim 1 , wherein the anode active material, the lithium insertion transition metal oxide or phosphate, or both are in a particulate form;
and wherein the particulate form ranges from 1 to 100 micrometers in average equivalent spherical diameter.
10. The electrochemical cell of claim 1 , wherein the electrochemical cell is charged to a lower voltage than an upper charging voltage.
11. The electrochemical cell of claim 1 , wherein the lithium insertion transition metal oxide or phosphate is selected from the group consisting of LiCoO 2 ; spinel LiMn 2 O 4 ; chromium-doped spinel lithium manganese oxides; layered LiMnO 2 ; LiNiO 2 ; LiNi x Co 1-x O 2 , wherein x is 0<x<1; LiNi 1-x-y Co x Mn y O 2 , wherein x is 0<x<1, and wherein y is 0<y<1; vanadium oxides; LiFePO 4 ; LiMnPO 4 ; and LiVPO 4 .
12. The electrochemical cell of claim 9 , wherein the lithium insertion transition metal oxide or phosphate, is a lithium insertion transition metal oxide selected from the group consisting of LiCoO 2 ; LiMn 2 O 4 ; LiNiO 2 ; LiNi x Co 1-x O 2 , wherein x is 0<x<1; LiNi 1-x-y Co x Mn y O 2 , wherein x is 0<x<1, and wherein y is 0<y<1.
13. The electrochemical cell of claim 1 , wherein the electrolyte solution comprises an organic carbonate.
14. The electrochemical cell of claim 13 , wherein the organic carbonate is selected from the group consisting of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and mixtures thereof.
15. The electrochemical cell of claim 1 , wherein the electrolyte solution is a solution of the lithium compound in an organic carbonate;
wherein a concentration of the lithium compound in the electrolyte solution is from about 0.1 to 2 molar; and
wherein the organic carbonate is selected from the group consisting of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate.
16. The electrochemical cell of claim 1 , wherein the film comprises a member selected from the group consisting of aluminum oxide, aluminum fluoride, aluminum oxalatoborate or other boron-containing compound, or a mixture thereof.
17. The electrochemical cell of claim 1 , wherein the additive is selected from the group consisting of LiF and LiAsF 6 .