Electrochemical cells with improved separator and electrolyte
View Patent ↗An electrochemical cell is described. The electrochemical cell includes an anode, a cathode, a separator between said anode and said cathode, and an electrolyte. The electrolyte includes a salt dissolved in an organic solvent. The separator in combination with the electrolyte has an area specific resistance less than 2 ohm-cm 2 .
1. An electrochemical cell comprising an anode, a cathode, a separator between said anode and said cathode, and an electrolyte, said cathode comprising iron disulfide, said electrolyte comprising a salt dissolved in an organic solvent, said organic solvent comprising a mixture of a cyclic ether-based solvent and an acyclic ether-based solvent, and said separator in combination with said electrolyte has an area specific resistance less than 2 ohm-cm 2 .
2. The electrochemical cell of claim 1 wherein the separator has a pore size between about 0.005 to about 5 micron.
3. The electrochemical cell of claim 1 wherein the separator has a tortuosity less than about 2.5.
4. The electrochemical cell of claim 1 wherein the separator has a porosity between about 30% and about 70%.
5. The electrochemical cell of claim 1 wherein the electrolyte comprises a plurality of salts dissolved in the organic solvent.
6. The electrochemical cell of claim 1 wherein the cyclic ether-based solvent comprises a dioxolane.
7. The electrochemical of claim 6 wherein the weight ratio of the acyclic ether-based solvent to the dioxolane is from 1:99 to 45:55.
8. The electrochemical cell of claim 7 wherein the weight ratio of the acyclic ether-based solvent to the dioxolane is from 10:90 to 40:60.
9. The electrochemical cell of claim 1 wherein the acyclic ether-based solvent is selected from the group consisting of dimethoxyethane, ethyl glyme, diglyme, dimethoxypropane, and triglyme.
10. The electrochemical cell of claim 9 wherein the acyclic ether-based solvent is 1,2-dimethoxyethane.
11. The electrochemical cell of claim 1 wherein the anode comprises lithium.
12. The electrochemical cell of claim 1 wherein the separator is wetted by the electrolyte.
13. The electrochemical cell of claim 1 wherein the separator has a thickness from about 8 to about 30 micrometers.