Additives for electrochemical cells
Articles and methods including additives in electrochemical cells, are generally provided. As described herein, such electrochemical cells may comprise an anode, a cathode, an electrolyte, and optionally a separator. In some embodiments, at least one of the anode, the cathode, the electrolyte, and/or the optional separator may comprise an additive and/or additive precursor. For instance, in some cases, the electrochemical cell comprises an electrolyte and an additive and/or additive precursor that is soluble with and/or is present in the electrolyte. In some embodiments, the additive precursor comprises a disulfide bond. In certain embodiments, the additive is a carbon disulfide salt. In some cases, the electrolyte may comprise a nitrate.
1. An electrochemical cell, comprising:
a first electrode comprising a first active electrode species comprising lithium;
a second electrode;
an electrolyte positioned between the first electrode and the second electrode;
an additive having a structure as in Formula (I) and/or an additive precursor having a structure as in Formula (II):
wherein:
each occurrence of Q is independently selected from the group consisting of Se, O, S, PR 2 , CR 2 2 , and SiR 2 2 ;
n is 1-6; and
each R 1 and R 2 are the same or different, optionally connected, and are independently selected from the group consisting of hydrogen; oxygen; sulfur; halogen; nitrogen; phosphorus; substituted or unsubstituted, branched or unbranched aliphatic; substituted or unsubstituted cyclic; substituted or unsubstituted, branched or unbranched acyclic; substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted aryl; and substituted or unsubstituted heteroaryl.
2. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor is polyanionic.
3. An electrochemical cell as in claim 1 , wherein the additive is a salt.
4. An electrochemical cell as in claim 1 , wherein the additive comprises a cation.
5. An electrochemical cell as in claim 4 , wherein the cation is selected from the group consisting of Li + , Na + , K + , Cs + , Rb + , Ca +2 , Mg +2 , substituted or unsubstituted ammonium, guanidinium and imidazolium.
6. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor comprises a xanthate group.
7. An electrochemical cell a as in claim 1 , wherein at least a portion of the additive and/or additive precursor is in solid form.
8. An electrochemical cell as in claim 1 , wherein at least a portion of the additive and/or additive precursor is dissolved in the electrolyte.
9. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor is at least partially soluble in the electrolyte.
10. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor is disposed on and/or within the first electrode.
11. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor is disposed on and/or within the second electrode.
12. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor is present in the electrolyte.
13. An electrochemical cell as in claim 1 , wherein the additive and any additive precursor is present in the electrolyte in a total amount ranging between about 0.5 wt % and about 20 wt % versus the total weight of the electrolyte and additive and/or additive precursor.
14. An electrochemical cell as in claim 1 , wherein the additive and any additive precursor is present in the electrolyte in a total amount ranging between about 0.5 wt % and about 10 wt % versus the weight of each of the first and second electrodes.
15. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor is disposed on and/or within a separator positioned between the first electrode and the second electrode.
16. An electrochemical cell as in claim 1 , wherein the additive and/or additive precursor is present in a reservoir positioned between the first electrode and the second electrode.
17. An electrochemical cell as in claim 1 , wherein the electrolyte comprises a nitrate.
18. An electrochemical cell as in claim 17 , wherein the nitrate is selected from the group consisting of LiNO 3 , guanidine nitrate, and pyridine nitrate.
19. An electrochemical cell as in claim 1 , wherein the electrolyte comprises one or more of a carbonate, a hexafluorophosphate, 1,3-dioxolane, 1,2-dimethoxyethane, a sulfonimide, sulfones, sulfolanes, esters of carbonic acid, and/or a nitrate-containing compound.
20. An electrochemical cell as in claim 1 , wherein the electrochemical cell includes a second active electrode species, wherein the second active electrode species comprises sulfur.
21. An electrochemical cell as in claim 1 , wherein the second electrode is an intercalated electrode.
22. An electrochemical cell, comprising:
a first electrode comprising a first active electrode species comprising lithium;
a second electrode;
an electrolyte positioned between the first electrode and the second electrode;
an additive having a structure as in Formula (I) and/or an additive precursor having a structure as in Formula (II):
wherein:
each occurrence of Q is independently selected from the group consisting of Se, O, S, PR 2 , NR 2 , CR 2 2 , and SiR 2 2 ;
n is 1-6;
each R 1 and R 2 are the same or different, optionally connected, and are independently selected from the group consisting of hydrogen; oxygen; sulfur; halogen; nitrogen; phosphorus; substituted or unsubstituted, branched or unbranched aliphatic; substituted or unsubstituted cyclic; substituted or unsubstituted, branched or unbranched acyclic; substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted aryl; and substituted or unsubstituted heteroaryl; and
the additive and/or the additive precursor is/are present in the electrochemical cell in a total amount of less than or equal to about 20 wt % versus the total weight of the electrolyte and the additive and/or additive precursor, or the additive and/or the additive precursor is/are present in the electrochemical cell in a total amount of less than or equal to about 4 wt % versus the weight of each of the first and second electrodes.
23. An electrochemical cell as in claim 22 , wherein the additive and/or additive precursor is/are present in the electrolyte.
24. An electrochemical cell as in claim 23 , wherein the additive and/or additive precursor is at least partially soluble in the electrolyte.
25. An electrochemical cell as claim 22 , wherein the additive and/or additive precursor is present in a reservoir positioned between the first electrode and the second electrode.
26. An electrochemical cell, comprising:
a first electrode comprising a first active electrode species;
a second electrode comprising a second active electrode species, wherein the second electrode is a lithium-intercalation cathode;
an electrolyte positioned between the first electrode and the second electrode;
an additive having a structure as in Formula (I) and/or an additive precursor having a structure as in Formula (II):
wherein:
each occurrence of Q is independently selected from the group consisting of Se, O, S, PR 2 , NR 2 , CR 2 2 , and SiR 2 2 ;
n is 1-6;
each R 1 and R 2 are the same or different, optionally connected, and are independently selected from the group consisting of hydrogen; oxygen; sulfur; halogen; nitrogen; phosphorus; substituted or unsubstituted, branched or unbranched aliphatic; substituted or unsubstituted cyclic; substituted or unsubstituted, branched or unbranched acyclic; substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted aryl; and substituted or unsubstituted heteroaryl; and
wherein the additive and/or the additive precursor is/are different from the first and second active electrode species.
27. A method, comprising:
introducing, into an electrochemical cell comprising a lithium-intercalation cathode, an additive having a structure as in Formula (I) and/or an additive precursor having a structure as in Formula (II):
wherein:
each occurrence of Q is independently selected from the group consisting of Se, O, S, NR 2 , PR 2 , CR 2 2 , and SiR 2 2 ;
n is 1-6;
each R 1 and R 2 are the same or different, optionally connected, and are independently selected from the group consisting of hydrogen; oxygen; sulfur; halogen; nitrogen; phosphorus; substituted or unsubstituted, branched or unbranched aliphatic; substituted or unsubstituted cyclic; substituted or unsubstituted, branched or unbranched acyclic; substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted aryl; and substituted or unsubstituted heteroaryl; and
wherein the electrode comprises active electrode species that is/are different from the additive and/or the additive precursor.
28. A method as in claim 27 , wherein introducing comprises adding to an electrolyte the additive having a structure as in Formula (I) and/or the additive precursor having a structure as in Formula (II).
29. A method as in claim 27 , wherein introducing comprises applying a coating to at least a portion of a surface of an electrode, the coating comprises the additive having a structure as in Formula (I) and/or the additive precursor having a structure as in Formula (II).
30. A method as in claim 29 , comprising drying the coating such that the additive or additive precursor is in solid form.
31. A method as in any claim 27 , wherein the electrolyte comprises a nitrate.
32. A method as in claim 27 , wherein the electrolyte comprises one or more of a carbonate, a hexafluorophosphate, 1,3-dioxolane, 1,2-dimethoxyethane, a sulfonimide, sulfones, sulfolanes, esters of carbonic acid, and/or a nitrate containing compound.
33. A method as in claims 27 , wherein the electrochemical cell includes a first active anode species, wherein the first active anode species comprises lithium.
34. A method, comprising:
introducing into an electrochemical cell or a component of an electrochemical cell comprising a first active electrode species comprising lithium an additive having a structure as in Formula (I) and/or an additive precursor having a structure as in Formula (II):
wherein:
each occurrence of Q is independently selected from the group consisting of Se, O, S, PR 2 , CR 2 2 , and SiR 2 2 ;
n is 1-6; and
each R 1 and R 2 are the same or different, optionally connected, and are independently selected from the group consisting of hydrogen; oxygen; sulfur; halogen; nitrogen; phosphorus; substituted or unsubstituted, branched or unbranched aliphatic; substituted or unsubstituted cyclic; substituted or unsubstituted, branched or unbranched acyclic; substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted aryl; and substituted or unsubstituted heteroaryl.