# US 2021/0242500 A1 · Electrolytes for fast charging lithium ion batteries having four-carbon chain esters as linear components

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2021/0242500 A1
- Document ID: US20210242500A1
- Status: Published application
- Kind: A1
- Application number: 16/774,003
- Filed: 2020-01-28
- Published: 2021-08-05
- Earliest claimed: 2020-01-28
- Assignees: StoreDot Ltd.
- Applicants: StoreDot Ltd.
- Inventors: Nir KEDEM; Liron AMIR; Evgenia Liel (Jeny) KUKS; Ido HERZOG; Shirel COHEN; Rony SCHWARZ; Eran SELLA
- Web page: https://patentgrep.com/patent/US20210242500A1

## CPC

- H01M 10/0569: characterised by the solvents
- H01M 4/38: of elements or alloys
- H01M 4/386: {Silicon or alloys based on silicon}
- H01M 4/387: {Tin or alloys based on tin}
- H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
- H01M 10/0567: characterised by the additives
- H01M 10/4235: {Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence)}
- H01M 2004/027: {Negative electrodes}
- H01M 2300/0037: Mixture of solvents
- H01M 2300/0051: Carbonates
- Y02E 60/10: Energy storage using batteries
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

Lithium ion batteries and electrolytes therefor are provided, which include electrolyte additives having dithioester functional group(s) that stabilize the SEI (solid-electrolyte interface) at the surfaces of the anode material particles, and/or stabilize the CEI (cathode electrolyte interface) at the surfaces of the cathode material particles, and/or act as oxygen scavengers to prevent cell degradation. The electrolyte additives having dithioester functional group(s) may function as polymerization controlling and/or chain transfer agents that regulate the level of polymerization of other electrolyte components, such as VC (vinyl carbonate) and improve the formation and operation of the batteries. The lithium ion batteries may have metalloid-based anodes—including mostly Si, Ge and/or Sn as anode active material particles.

## Claims

### Claim 1

An electrolyte solution for a fast charging a lithium ion battery, comprising:
linear solvent comprising at least one four-carbon chain ester,
cyclic carbonate solvent comprising at least vinyl carbonate (VC) solvent,
additives at an amount smaller than 5 wt %, and
at least one lithium salt,
wherein the at least one four-carbon chain ester is represented by the structure of Formula (XVIa), Formula (XVIb) or any combination thereof:
wherein
R45′ is a C3-C10 alkyl, C3-C20 alkyl or C3-C30 alkyl;
R46′ is C4-C10 alkyl, C4-C20 alkyl or C4-C30 alkyl;
R48 is alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl;
R49 is alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl;
each of the alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl of R8, R48′, R49 or R49′ is optionally substituted with one or more of alkyl, haloalkyl, alkenyl, alkynyl, heteroalicyclic, heteroaryl, O—P(═O)(OR48)2, trihalomethyl, cyano, S(═O)—R48, S(═O)2—R48, S(═O)2—NR48R49, halide, cycloalkyl, alkoxy, nitro, NR48R49, C(O)NR48R49, N(R48)C(═O)—R49, hydroxy, alkylthiol, thiol, arylthiol, heteroarylthiol, C(═O)—OR48, C(═O)—R48, aryl, aryloxy, heteroaryloxy, (CH2CH2O)n+1 or any combination thereof; and
n is an integer between 0 and 10.

### Claim 2 (depends on 1)

The electrolyte solution of claim 1, wherein R48 is a C3-C10 alkyl, C3-C20 alkyl or C3-C30 alkyl.

### Claim 3 (depends on 1)

The electrolyte solution of claim 1, wherein R49 is a C4-C10 alkyl, C4-C20 alkyl or C4-C30 alkyl.

### Claim 4 (depends on 1)

The electrolyte solution of claim 1, wherein the VC solvent is at 10-30 wt % and the at least one four-carbon chain ester is at 90-70 wt %, respectively.

### Claim 5 (depends on 1)

The electrolyte solution of claim 1, wherein a weight percentage of the at least one four-carbon chain ester is larger than a weight percentage of the cyclic carbonate solvent.

### Claim 6 (depends on 1)

The electrolyte solution of claim 1, further comprising at least one additive that comprises at least one of: compound 1a, compound 35, compound 36, LiFOB and tertamilbenzene (t-AmB), with

### Claim 7 (depends on 1)

A lithium ion battery comprising the electrolyte solution of claim 1, at least one anode and at least one cathode separated by at least one separator, wherein the anode has anode material based on metalloids comprising at least one of Si, Ge and/or Sn, and the battery is chargeable at least at 4 C.

### Claim 8

An electrolyte solution for a fast charging lithium ion battery, comprising:
linear solvent comprising at least one four-carbon chain ester,
cyclic carbonate solvent comprising at least vinyl carbonate (VC) solvent,
wherein a weight percentage of the at least one four-carbon chain ester is larger than a weight percentage of the cyclic carbonate solvent,
at least one lithium salt, and
at least one additive is represented by tertamilbenzene (t-AmB):
the structure of Formula (I) or any combination thereof:
wherein:
Z1 is halide, alkyl, haloalkyl, aryl, alkenyl, alkynyl, cycloalkyl, heteroaryl, heteroalicyclic, hydroxyl, alkoxy, aryloxy, heteroaryloxy, NR1R2, P(═O)R1R2, benzyl, thiol, arylthiol, alkylthiol, heteroarylthiol, O(CH2)nC4H4S, amino pyridine, imidazole, cyclic amine, piperazine, N(CH2CH2)2N—C(═S)—S—Z2, a polymeric moiety or an oligomeric moiety;
Z2 is alkyl, haloalkyl, benzyl, aryl, cycloalkyl, alkenyl, alkynyl, heteroalicyclic, heteroaryl, a polymeric moiety, CH(P(═O)(OR1)2)((C═O)OR2), CH2C6H5, (CH2)n(CO)NR1R2, (CH2)nCOOR1, (CH2)n(CO)NH(C5H4N), (CH2)nSR1, (CH2)nS(═O)R1, (CH2)nS(═O)2R1,
an oligomeric moiety or S—C(═S)—Z1;
R1-R2 are each independently H, alkyl, haloalkyl, cycloalkyl, benzyl, aryl, heteroalicyclic, heteroaryl, polymeric moiety or an oligomeric moiety, wherein if nitrogen (N) is adjacent to R1 and R2 then R1, R2 and the adjacent nitrogen may form a heteroaryl or a heteroalicyclic ring;
each of the alkyl, haloalkyl, aryl, benzyl, alkenyl, alkynyl, cycloalkyl, heteroaryl, heteroalicyclic, alkoxy, aryloxy, heteroaryloxy, polymeric moiety, oligomeric moiety arylthiol, alkylthiol or heteroarylthiol of Z1, Z2, R1 or R2 is optionally substituted with one or more of alkyl, haloalkyl, alkenyl, alkynyl, heteroalicyclic, heteroaryl, O—P(═O)(OR1)2, trihalomethyl, S(═O)—R1, S(═O)2—R1, S(═O)2—NR1R2, halide, cycloalkyl, alkoxy, nitro, cyano, NR1R2, C(O)NR1R2, N(R1)C(═O)—R2, hydroxy, alkylthiol, thiol, arylthiol, heteroarylthiol, C(═O)—OR1, C(═O)—R1, aryl, aryloxy, heteroaryloxy, (CH2CH2O)n+1 or any combination thereof; and n is an integer between 0 and 10.

### Claim 9 (depends on 8)

The electrolyte solution of claim 8, wherein the at least one additive is represented by the structure of Formula (Ia), (Iai) or any combination thereof:
wherein
R3 and R3′ are each independently H, alkyl, haloalkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroalicyclic heteroaryl, alkoxy, hydroxy, O—P(═O)(OR1)2, thiol, alkylthiol, aryloxy, heteroaryloxy, arylthiol, heteroarylthiol, nitro, halide, trihalomethyl, cyano, benzyl, C(O)NR1R2, NR3R2, N(R1)C(═O)—R2, C(═O)—OR1, S(═O)—R1, S(═O)2—R1 or S(═O)2—NR1R2;
R4 is H, alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl;
each of the alkyl, haloalkyl, cycloalkyl, aryl, benzyl, heteroaryl, alkenyl, alkynyl, heteroalicyclic, alkoxy, alkylthiol, heteroarylthiol, aryloxy, heteroaryloxy or arylthiol of R1, R2, R3, R3′ or R4 is optionally substituted with one or more of alkyl, haloalkyl, alkenyl, alkynyl, heteroalicyclic, heteroaryl, O—P(═O)(OR1)2, trihalomethyl, cyano, S(═O)—R1, S(═O)2—R1, S(═O)2—NR1R2, halide, cycloalkyl, alkoxy, nitro, NR4R2, C(O)NR1R2, N(R1)C(═O)—R2, hydroxy, alkylthiol, thiol, arylthiol, heteroarylthiol, C(═O)—OR1, C(═O)—R1, aryl, aryloxy, heteroaryloxy, (CH2CH2O)n+1 or any combination thereof; and
n is an integer between 0 and 10.

### Claim 10 (depends on 8)

The electrolyte solution of claim 8, wherein the at least one additive comprises at least one of: compound 1a, compound 35, compound 36, LiFOB and tertamilbenzene (t-AmB), with

### Claim 11 (depends on 8)

The electrolyte solution of claim 8, comprising 10-30 wt % VC and 90-70 wt % of the at least one four-carbon chain ester, respectively.

### Claim 12 (depends on 8)

The electrolyte solution of claim 8, comprising the compound 1a additive between 0.3-0.9 wt % of the total solvent.

### Claim 13 (depends on 8)

The electrolyte solution of claim 8, comprising the compound 35 additive between 0.3-0.9 wt % of the total solvent.

### Claim 14 (depends on 8)

The electrolyte solution of claim 8, comprising the LiFOB additive between 1-5 wt % of the total solvent.

### Claim 15 (depends on 8)

The electrolyte solution of claim 8, comprising the t-AmB additive between 0.5-5 wt % of the total solvent.

### Claim 16 (depends on 8)

The electrolyte solution of claim 8, wherein the at least one four-carbon chain ester is ethyl butyrate and/or butyl acetate.

### Claim 17 (depends on 8)

The electrolyte solution of claim 8, wherein the at least one four-carbon chain ester is represented by the structure of Formula (XVIa), Formula (XVIb) or any combination thereof:
wherein
R45′ is a C3-C10 alkyl, C3-C20 alkyl or C3-C30 alkyl;
R46′ is C4-C10 alkyl, C4-C20 alkyl or C4-C30 alkyl;
R48 is alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl;
R49 is alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl;
each of the alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl of R8, R48′, R49 or R49′ is optionally substituted with one or more of alkyl, haloalkyl, alkenyl, alkynyl, heteroalicyclic, heteroaryl, O—P(═O)(OR48)2, trihalomethyl, cyano, S(═O)—R48, S(═O)2—R48, S(═O)2—NR48R49, halide, cycloalkyl, alkoxy, nitro, NR48R49, C(O)NR48R49, N(R48)C(═O)—R49, hydroxy, alkylthiol, thiol, arylthiol, heteroarylthiol, C(═O)—OR48, C(═O)—R48, aryl, aryloxy, heteroaryloxy, (CH2CH2O)n+1 or any combination thereof; and
n is an integer between 0 and 10.

### Claim 18 (depends on 8)

The electrolyte solution of claim 8, wherein the linear solvent further comprises at least one of dimethyl carbonate (DMC), ethyl methyl carbonate (EMC) and diethyl carbonate (DEC), at an amount of 35 vol % or less of the electrolyte solution.

### Claim 19 (depends on 8)

A lithium ion battery comprising the electrolyte solution of claim 8, at least one anode and at least one cathode separated by at least one separator, wherein the anode has anode material based on metalloids comprising at least one of Si, Ge and/or Sn, and the battery is chargeable at least at 4 C.

### Claim 20

A method of enhancing safety and performance of fast charging lithium ion batteries, the method comprising replacing at least part of a linear solvent of an electrolyte solution with at least one four-carbon chain ester at a higher concentration than a cyclic carbonate solvent in the electrolyte solution.

### Claim 21 (depends on 20)

The method of claim 20, further comprising:
using the at least one four-carbon chain ester as a main linear solvent of the electrolyte solution, and
using VC as a main cyclic carbonate solvent of the electrolyte solution, with the VC being at a smaller weight percentage than the at least one four-carbon chain ester.

### Claim 22 (depends on 20)

The method of claim 20, further comprising adding to the electrolyte solution at least one additive that comprises at least one of: compound 1a, compound 35, compound 36, LiFOB and Tertamilbenzene (t-AmB), with

### Claim 23 (depends on 20)

The method of claim 20, wherein the at least one four-carbon chain ester is represented by the structure of Formula (XVIa), Formula (XVIb) or any combination thereof:
wherein
R45′ is a C3-C10 alkyl, C3-C20 alkyl or C3-C30 alkyl;
R46′ is C4-C10 alkyl, C4-C20 alkyl or C4-C30 alkyl;
R48 is alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl;
R49 is alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl;
each of the alkyl, haloalkyl, cycloalkyl, aryl, heteroalicyclic, benzyl or heteroaryl of R8, R48′, R49 or R49′ is optionally substituted with one or more of alkyl, haloalkyl, alkenyl, alkynyl, heteroalicyclic, heteroaryl, O—P(═O)(OR48)2, trihalomethyl, cyano, S(═O)—R48, S(═O)2—R48, S(═O)2—NR48R49, halide, cycloalkyl, alkoxy, nitro, NR48R49, C(O)NR48R49, N(R48)C(═O)—R49, hydroxy, alkylthiol, thiol, arylthiol, heteroarylthiol, C(═O)—OR48, C(═O)—R48, aryl, aryloxy, heteroaryloxy, (CH2CH2O)n+1 or any combination thereof; and
n is an integer between 0 and 10.