ELECTRODE PROTECTION USING A COMPOSITE COMPRISING AN ELECTROLYTE-INHIBITING ION CONDUCTOR
Composite structures including an ion-conducting material and a polymeric material (e.g., a separator) to protect electrodes are generally described. The ion-conducting material may be in the form of a layer that is bonded to a polymeric separator. The ion-conducting material may comprise a lithium oxysulfide having a lithium-ion conductivity of at least at least 10 −6 S/cm.
1 . An electrochemical cell, comprising:
a first electrode comprising lithium;
a second electrode;
a separator arranged between said first electrode and said second electrode; and
a solid ion conductor contacting and/or bonded to the separator,
wherein said solid ion conductor comprises a lithium oxysulfide.
2 . An electrochemical cell, comprising:
a first electrode comprising lithium;
a second electrode;
a separator arranged between said first electrode and said second electrode, wherein the separator comprises pores; and
a solid ion conductor contacting and/or bonded to the separator;
wherein said solid ion conductor is substantially formed of a non-polymeric material, wherein the solid ion conductor comprises a lithium oxysulfide, wherein the solid ion conductor is present in the form of a layer, wherein the layer coats the separator, and wherein a thickness of the layer is at least 1.1 times an average pore size of the separator and less than or equal to 20 times the average pore size of the separator.
3 . An electrochemical cell, comprising:
a first electrode comprising lithium;
a second electrode;
a separator arranged between said first electrode and said second electrode; and
a solid ion conductor contacting and/or bonded to the separator;
wherein said solid ion conductor is substantially formed of a non-polymeric material, wherein the solid ion conductor comprises a lithium oxysulfide, wherein the solid ion conductor is present in the form of a layer, and wherein an RMS surface roughness of the layer is between 0.5 nm and 1 micron.
4 . The electrochemical cell of claim 1 , wherein the separator comprises pores.
5 . The electrochemical cell of claim 1 , wherein the solid ion conductor is substantially formed of a non-polymeric material.
6 . The electrochemical cell of claim 1 , wherein the solid ion conductor is present in the form of a layer.
7 . The electrochemical cell of claim 6 , wherein the separator comprises pores and wherein a thickness of the layer is at least 1.1 times an average pore size of the separator and less than or equal to 20 times the average pore size of the separator.
8 . The electrochemical cell of claim 6 , wherein an RMS surface roughness of the layer is between 0.5 nm and 1 micron.
9 . The electrochemical cell of claim 6 , wherein the layer coats the separator.
10 . The electrochemical cell of claim 6 , wherein the layer has a lithium-ion conductivity of at least 10 −6 S/cm and less than 20 S/cm.
11 . The electrochemical cell of claim 1 , wherein the separator has a bulk electronic resistivity of at least about 10 4 Ohm-meters.
12 . The electrochemical cell of claim 1 , wherein the lithium oxysulfide has an oxide content between 0.1-20 wt %.
13 . The electrochemical cell of claim 1 , wherein the lithium oxysulfide has an atomic ratio of oxygen atoms to sulfur atoms (O:S) in the range of from 0.001:1 to 1.5:1.
14 . The electrochemical cell of claim 1 , wherein the lithium oxysulfide has an atomic ratio of oxygen atoms to sulfur atoms (O:S) in the range of from 0.01:1 to 0.25:1.
15 . The electrochemical cell of claim 1 , wherein the lithium oxysulfide has a formula of x(yLi 2 S+zLi 2 O)+MS 2 (where M is Si, Ge, or Sn), where y+z=1, and where x may range from 0.5-3.
16 . The electrochemical cell of claim 6 , wherein a strength of adhesion between the separator and the layer is at least 50 N/m and less than or equal to 2000 N/m and/or passes the tape test according to the standard ASTM D3359-02.
17 . The electrochemical cell of claim 1 , wherein the lithium oxysulfide has a lithium ion conductivity of at least 10 −7 S/cm and less than or equal to 20 S/cm.
18 . The electrochemical cell of claim 6 , wherein the layer has a thickness of between 1 nm and 7 microns.
19 . The electrochemical cell of claim 1 , wherein an air permeation time of the separator is at least 1,000 Gurley-s and less than or equal to 10 6 Gurley-s.
20 . The electrochemical cell of claim 1 , wherein the solid ion conductor is one or more of a ceramic, a glass, or a glassy ceramic.