Silicon-based energy storage devices with functional terthiophene compound or thiophene oligomer compound containing electrolyte additives

1. An energy storage device comprising:

a first electrode and a second electrode, wherein at least one of the first electrode and the second electrode is a Si-based electrode;

a separator between the first electrode and the second electrode;

an electrolyte; and

at least one electrolyte additive comprising a thiophene oligomer compound,

wherein the thiophene oligomer compound is of formula (I):

which may be optionally substituted and wherein n=4−8.

2. The energy storage device of claim 1 , wherein the second electrode is a Si-dominant electrode.

3. The energy storage device of claim 1 , wherein the second electrode comprises a self-supporting composite material film.

4. The energy storage device of claim 3 , wherein the composite material film comprises: greater than 0% and less than about 90% by weight of silicon particles, and greater than 0% and less than about 90% by weight of one or more types of carbon phases, wherein at least one of the one or more types of carbon phases is a substantially continuous phase that holds the composite material film together such that the silicon particles are distributed throughout the composite material film.

5. The energy storage device of claim 1 , wherein the electrolyte further comprises fluoroethylene carbonate (FEC).

6. The energy storage device of claim 5 , wherein the electrolyte is substantially free of non-fluorine containing cyclic carbonate.

7. The energy storage device of claim 1 , wherein the electrolyte additive is selected from the group consisting of 2,2′:5′,2″:5″,2″′-Quaterthiophene (CAS: 5632-29-1); 2,2′:3′,2″:3″,2″′-Quaterthiophene; 5,5″′-Dimethyl-2,2′:5′,2″:5″,2″′-quaterthiophene; 3,4-dimethyl-2-[3-(3-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophene; 3,3″′-Dimethyl-2,2′:3′,2″:3″,2″′-quaterthiophene; 2-(3-prop-2-enylthiophen-2-yl)-5-[5-(3-prop-2-enylthiophen-2-yl)thiophen-2-yl]thiophene; 5-cyano-2,2′:5′,2″:5″,2″′-tetrathiophene; 3″′,4″′-Diethynyl-2,2′:3′,2″:3″,2″′-quaterthiophene; Tetracyanoquaterthiophene; 2-[3-(1,1,2,2,3,3,4,4,5,5,6,6,7,7,7-pentadecafluoroheptyl)thiophen-2-yl]-5-[5-[3-(1,1,2,2,3,3,4,4,5,5,6,6,7,7,7-pentadecafluoroheptyl)thiophen-2-yl]thiophen-2-yl]thiophene; 2-(5-methylthiophen-2-yl)-5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]-3-(3,3,4,4-tetrafluoropent-1-en-2-yl)thiophene; 5-methyl-2-[5-[5-(5-methyl-3-propylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-3-(3,3,3-trifluoropropyl)thiophene, Quinquethiophene; 3,2′:5′,2″:5″,2″′:5″′,3″″-Quinquethiophene; 2,3,4,5-tetrathiophenyl-thiophene; 3-butyl-5-thiophen-2-yl-2-[5-(5-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophene; 2-(3-methylthiophen-2-yl)-5-[5-[5-(3-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophene; 3-methyl-5-[5-[4-methyl-5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-2-(5-methylthiophen-2-yl)thiophene; 3,2′:5′,2″:5″,2″′:5″′,2″ ″:5″ ″,3″″′-Sexithiophene; 2-thiophen-2-yl-3-[3-[3-(3-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophene; 2-(3,5-dithiophen-2-ylthiophen-2-yl)-3,5-dithiophen-2-ylthiophene; 2,3,4-trithiophen-2-yl-5-(3-thiophen-2-ylthiophen-2-yl)thiophene; 3-methyl-5-[4-methyl-5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-2-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophene; 3-methyl-5-(5-methylthiophen-2-yl)-2-[5-[5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophene; 5,5′-Bis(2,2′-bithiophene-5-yl)-3,3′-dimethyl-2,2′-bithiophene; 3-methyl-2-[3-methyl-5-[4-methyl-5-(3-methyl-5-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-5-thiophen-2-ylthiophene, Septithiophene; 3-methyl-2-[5-[5-[5-[3-methyl-5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]-5-(5-methylthiophen-2-yl)thiophene; 2-thiophen-2-yl-3-[3-[3-[3-[3-(3-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophene; 3-methyl-5-[3-methyl-5-[5-[5-[4-methyl-5-[4-methyl-5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]-2-(5-methylthiophen-2-yl)thiophene; and 3-methyl-5-[4-methyl-5-[5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]-2-[5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophene.

8. A method of forming an energy storage device, the method comprising:

forming an energy storage device comprising a cathode, an electrolyte, and an anode,

wherein said electrolyte is formed by adding an electrolyte additive to an electrolyte composition and,

wherein said electrolyte additive is a thiophene oligomer compound of formula (I):

which may be optionally substituted and wherein n=4−8.

9. The method of claim 8 , wherein the anode is a Si-dominant electrode.

10. The method of claim 8 , wherein the anode comprises a self-supporting composite material film.

11. The method of claim 10 , wherein the composite material film comprises:

greater than 0% and less than about 90% by weight of silicon particles, and

greater than 0% and less than about 90% by weight of one or more types of carbon phases, wherein at least one of the one or more types of carbon phases is a substantially continuous phase that holds the composite material film together such that the silicon particles are distributed throughout the composite material film.

12. The method of claim 8 , wherein the electrolyte further comprises fluoroethylene carbonate (FEC).

13. The method of claim 12 , wherein the electrolyte is substantially free of non-fluorine containing cyclic carbonate.

14. The method of claim 8 , wherein the electrolyte additive is selected from the group consisting of 2,2′:5′,2″:5″,2′″-Quaterthiophene (CAS: 5632-29-1); 2,2′:3′,2″:3″,2′″-Quaterthiophene; 5,5′″-Dimethyl-2,2′:5′,2″:5″,2′″-quaterthiophene; 3,4-dimethyl-2-[3-(3-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophene; 3,3′″-Dimethyl-2,2′:3′,2″:3″,2′″-quaterthiophene; 2-(3-prop-2-enylthiophen-2-yl)-5-[5-(3-prop-2-enylthiophen-2-yl)thiophen-2-yl]thiophene; 5-cyano-2,2′:5′,2″:5″,2′″-tetrathiophene; 3′″,4′″-Diethynyl-2,2′:3′,2″:3″,2′″-quaterthiophene; Tetracyanoquaterthiophene; 2-[3-(1,1,2,2,3,3,4,4,5,5,6,6,7,7,7-pentadecafluoroheptyl)thiophen-2-yl]-5-[5-[3-(1,1,2,2,3,3,4,4,5,5,6,6,7,7,7-pentadecafluoroheptyl)thiophen-2-yl]thiophen-2-yl]thiophene; 2-(5-methylthiophen-2-yl)-5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]-3-(3,3,4,4-tetrafluoropent-1-en-2-yl)thiophene; 5-methyl-2-[5-[5-(5-methyl-3-propylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-3-(3,3,3-trifluoropropyl)thiophene, Quinquethiophene; 3,2′:5′,2″:5″,2′″:5′″,3′″-Quinquethiophene; 2,3,4,5-tetrathiophenyl-thiophene; 3-butyl-5-thiophen-2-yl-2-[5-(5-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophene; 2-(3-methylthiophen-2-yl)-5-[5-[5-(3-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophene;3-methyl-5-[5-[4-methyl-5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-2-(5-methylthiophen-2-yl)thiophene; 3,2′:5′,2″:5″,2′″:5′″,2″″,5″″, 3′″″-Sexithiophene; 2-thiophen-2-yl-3-[3-[3-(3-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophene; 2-(3,5-dithiophen-2-ylthiophen-2-yl)-3,5-dithiophen-2-ylthiophene; 2,3,4-trithiophen-2-yl-5-(3-thiophen-2-ylthiophen-2-yl)thiophene; 3-methyl-5-[4-methyl-5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-2-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophene; 3-methyl-5-(5-methylthiophen-2-yl)-2-[5-[5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophene; 5,5′-Bis(2,2′-bithiophene-5-yl)-3,3′-dimethyl-2,2′-bithiophene; 3-methyl-2-[3-methyl-5-[4-methyl-5-(3-methyl-5-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-5-thiophen-2-ylthiophene, Septithiophene; 3-methyl-2-[5-[5-[5-[3-methyl-5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]-5-(5-methylthiophen-2-yl)thiophene; 2-thiophen-2-yl-3-[3-[3-[3-[3-(3-thiophen-2-ylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophene; 3-methyl-5-[3-methyl-5-[5-[5-[4-methyl-5-[4-methyl-5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]-2-(5-methylthiophen-2-yl)thiophene; and 3-methyl-5-[4-methyl-5-[5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophen-2-yl]-2-[5-[5-(5-methylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]thiophene.