| CPC H01M 10/0569 (2013.01) [H01M 4/133 (2013.01); H01M 4/134 (2013.01); H01M 4/621 (2013.01); H01M 10/052 (2013.01); H01M 10/0567 (2013.01); H01M 50/103 (2021.01)] | 4 Claims |

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1. A rectangular-shaped non-aqueous electrolyte secondary battery, comprising:
a positive electrode;
a negative electrode; and
a non-aqueous electrolyte having an electrolyte salt and a non-aqueous solvent,
wherein the negative electrode comprises:
a negative electrode current collector; and
a negative electrode mixture layer formed on the negative electrode current collector,
the negative electrode mixture layer has:
a first layer formed on the negative electrode current collector, the first layer including a first carbon-based active material, a Si-based active material, and polyacrylic acid or a salt thereof; and
a second layer formed on the first layer, the second layer including a second carbon-based active material,
the first carbon-based active material has a tap density of 0.86 g/cm3 to 0.89 g/cm3 and a BET specific surface area of 3.9 m2/g to 6.8 m2/g,
the second carbon-based active material has a tap density of 1.03 g/cm3 to 1.08 g/m3 and a BET specific surface area of 2.8 m2/g to 3.1 m2/g,
the mass of the first layer is 50% by mass or more and less than 90% by mass based on the mass of the negative electrode mixture layer, the mass of the second layer is more than 10% by mass and 50% by mass or less based on the mass of the negative electrode mixture layer,
the non-aqueous solvent includes a cyclic carbonate,
the total content of the cyclic carbonate is 20% by volume or more and 30% by volume or less based on the total volume of the non-aqueous solvent,
the content of fluoroethylene carbonate belonging to the cyclic carbonate is more than 0% by volume and 20% by volume or less based on the total volume of the non-aqueous solvent,
the content of ethylene carbonate belonging to the cyclic carbonate is 10% by volume or less based on the total volume of the non-aqueous solvent,
the non-aqueous electrolyte includes vinylene carbonate, and
the content of the vinylene carbonate in the non-aqueous electrolyte is 0.2% by mass or more and 5% by mass or less.
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