Lithium-ion battery

Abstract

To provide a lithium secondary battery that suppresses increase in battery thickness and decrease in battery life even when a negative electrode is made denser.SOLUTION: The lithium secondary battery includes a positive electrode containing a positive electrode active material; a negative electrode containing a negative electrode active material; and an electrolyte. The electrode density of the negative electrode is 1.7 g / cc or more. The electrolyte includes a lithium salt; a non-aqueous organic solvent; a first additive represented by the following chemical formula 1; and a second additive represented by the following chemical formula 2. (An explanation of the chemical formulas is as described in the specification.)SELECTED DRAWING: Figure 1

Claims

1. Positive electrode containing positive electrode active material; A negative electrode containing a negative electrode active material; and Contains electrolyte, The electrode density of the negative electrode is 1.7 g / cc or more. The aforementioned electrolyte is Lithium salt; Non-aqueous organic solvents; The first additive represented by the following chemical formula 1; and It contains a second additive represented by the following chemical formula 2, The first additive is present in an amount of 1 to 20% by weight relative to the total amount of the electrolyte, and the second additive is present in an amount of 1 to 10% by weight. The first additive is represented by the following chemical formula 1-1-1, 【Chemistry 1】 The second additive is represented by the following chemical formula 2-1-1, and is a lithium secondary battery. 【Chemistry 2】

2. The lithium secondary battery according to claim 1, wherein the weight ratio of the first additive and the second additive is 20:1 to 2:

1.

3. The lithium secondary battery according to claim 1, wherein the non-aqueous organic solvent includes carbonate-based solvents and propionate-based solvents.

4. The lithium secondary battery according to claim 3, wherein the propionate solvent is present in an amount of 70% by volume or more relative to the total amount of the non-aqueous organic solvent.

5. The aforementioned lithium salt is LiPF 6 The lithium secondary battery according to claim 1.

6. The lithium secondary battery according to claim 1, wherein the concentration of the lithium salt is 0.1 M to 2.0 M.

7. The lithium secondary battery according to claim 1, wherein the positive electrode active material includes a lithium nickel oxide, a lithium cobalt oxide, a lithium manganese oxide, a lithium iron phosphate compound, a cobalt-free nickel-manganese oxide, or a combination thereof.

8. The lithium secondary battery according to claim 1, wherein the negative electrode active material includes a carbon-based negative electrode active material, a Si-based negative electrode active material, or a combination thereof.

9. The lithium secondary battery according to claim 1, wherein the upper limit charging voltage of the lithium secondary battery is 4.5V or higher.

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