Electrolyte and electrochemical device comprising the same
AssigneeNingde Amperex Technology Limited
InventorKefei Wang
Life of this patent
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Abstract
An electrolyte includes a fluorinated cyclic carbonate, a multi-nitrilemulti-nitrile compound having an ether bond and a compound having a sulfur-oxygen double bond. Based on a total weight of the electrolyte, a weight percentage (Cf) of the fluorinated cyclic carbonate is greater than a weight percentage (Cn) of the multi-nitrilemulti-nitrile compound having an ether bond. The electrolyte can control the expansion of the electrochemical device, so that the electrochemical device has excellent cycle, storage and/or floating-charge performance.
Claims24
An electrochemical device, comprising an electrode and an electrolyte, wherein the electrolyte comprises a fluorinated cyclic carbonate, a multi-nitrile compound having an ether bond, a dinitrile compound, and a compound having a sulfur-oxygen double bond;
- wherein
- the compound having a sulfur-oxygen double bond comprises at least one selected from the group consisting of 1,2-ethylene sulfate, 1,3-propanesultone, 1-fluoro-1,3-propanesultone, 2-fluoro-1,3-propanesultone, 3-fluoro-1,3-propanesultone, 1-methyl-1,3-propanesultone, 2-methyl-1,3-propanesultone, 3-methyl-1,3-propanesultone, 1-propene-1,3-sultone, 2-propene-1,3-sultone, 1-fluoro-1-propene-1,3-sultone, 2-fluoro-1-propene-1,3-sultone, 3-fluoro-1-propene-1,3-sultone, 1-fluoro-2-propene-1,3-sultone, 2-fluoro-2-propene-1,3-sultone, 3-fluoro-2-propene-1,3-sultone, 1-methyl-1-propene-1,3-sultone, 2-methyl-1-propene-1,3-sultone, 3-methyl-1-propene-1,3-sultone, 1-methyl-2-propene-1,3-sultone, 2-methyl-2-propene-1,3-sultone, 3-methyl-2-propene-1,3-sultone, 1,4-butane sultone, 1,5-pentane sultone, methylene methanedisulfonate, and ethylene methanedisulfonate;
- and
- the dinitrile compound comprises at least one selected from the group consisting of succinonitrile and adiponitrile;
- wherein based on a total weight of the electrolyte, a weight percentage (Cf) of the fluorinated cyclic carbonate is greater than a weight percentage (Cn) of the multi-nitrile compound having an ether bond;
- and wherein,
- based on a total weight of the electrolyte, a weight percentage of the compound having a sulfur-oxygen double bond is less than 4%;
- wherein the electrode comprises a current collector of two different regions, each region coated with either a single-sided coating or a double-sided coating, wherein the single-sided coating is formed by coating a slurry only on one surface of the current collector;
- and the double-sided coating is formed by coating a slurry on two opposing surfaces of the current collector, and
- wherein the electrode including the single-sided coating has an electrode compaction density D1, the electrode including the double-sided coating has an electrode compaction density D2, and D1 and D2 satisfy the relationship:
- about 0.8≤D1/D2≤about 1.2.
An electronic device, comprising an electrochemical device, the electrochemical device comprises an electrode and an electrolyte wherein the electrolyte comprises a fluorinated cyclic carbonate, a multi-nitrile compound having an ether bond, a dinitrile compound, and a compound having a sulfur-oxygen double bond;
- wherein
- the compound having a sulfur-oxygen double bond comprises at least one selected from the group consisting of 1,2-ethylene sulfate, 1,3-propanesultone, 1-fluoro-1,3-propanesultone, 2-fluoro-1,3-propanesultone, 3-fluoro-1,3-propanesultone, 1-methyl-1,3-propanesultone, 2-methyl-1,3-propanesultone, 3-methyl-1,3-propanesultone, 1-propene-1,3-sultone, 2-propene-1,3-sultone, 1-fluoro-1-propene-1,3-sultone, 2-fluoro-1-propene-1,3-sultone, 3-fluoro-1-propene-1,3-sultone, 1-fluoro-2-propene-1,3-sultone, 2-fluoro-2-propene-1,3-sultone, 3-fluoro-2-propene-1,3-sultone, 1-methyl-1-propene-1,3-sultone, 2-methyl-1-propene-1,3-sultone, 3-methyl-1-propene-1,3-sultone, 1-methyl-2-propene-1,3-sultone, 2-methyl-2-propene-1,3-sultone, 3-methyl-2-propene-1,3-sultone, 1,4-butane sultone, 1,5-pentane sultone, methylene methanedisulfonate, and ethylene methanedisulfonate;
- and
- the dinitrile compound comprises at least one selected from the group consisting of succinonitrile and adiponitrile;
- wherein based on a total weight of the electrolyte, a weight percentage (Cf) of the fluorinated cyclic carbonate is greater than a weight percentage (Cn) of the multi-nitrile compound having an ether bond;
- and wherein,
- based on a total weight of the electrolyte, a weight percentage of the compound having a sulfur-oxygen double bond is less than 4%;
- wherein the electrode comprises a current collector of two different regions, each region coated with either a single-sided coating or a double-sided coating, wherein the single-sided coating is formed by coating a slurry only on one surface of the current collector;
- and the double-sided coating is formed by coating a slurry on two opposing surfaces of the current collector, and
- wherein the electrode including the single-sided coating has an electrode compaction density D1, the electrode including the double-sided coating has an electrode compaction density D2, and D1 and D2 satisfy the relationship:
- about 0.8≤D1/D2≤about 1.2.
The electrochemical device according to 1 wherein, 1 wt %<Cf<3 wt %, or 2 wt %≤Cf+Cn<4 wt %.
Dependencies are inferred from the claim text.