| CPC H01M 4/366 (2013.01) [H01M 4/0404 (2013.01); H01M 4/386 (2013.01); H01M 4/505 (2013.01); H01M 4/525 (2013.01); H01M 4/587 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01); H01M 2220/20 (2013.01)] | 18 Claims |

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1. A secondary battery, comprising a negative electrode plate, wherein the negative electrode plate comprises a negative electrode current collector and a negative electrode film;
the negative electrode film comprises a first negative electrode coating layer and a second negative electrode coating layer;
the first negative electrode coating layer is disposed on at least one surface of the negative electrode current collector and comprises a first negative electrode active material, the first negative electrode active material comprises artificial graphite and a silicon-based material;
the second negative electrode coating layer is disposed on a surface of the first negative electrode coating layer and comprises a second negative electrode active material, and the second negative electrode active material comprises artificial graphite and a silicon-based material;
the silicon-based material is present at a mass percentage denoted as W1 in the first negative electrode active material, the silicon-based material is present at a mass percentage denoted as W2 in the second negative electrode active material, and the negative electrode plate satisfies: W2>W1 and W1+W2≤6%; and
the silicon-based material comprises a first silicon-based material and a second silicon-based material, and the first silicon-based material has a particle size smaller than that of the second silicon-based material and
the first silicon-based material has a particle size of greater than 0.05 μm and less than 7 μm; and
the second silicon-based material has a particle size of greater than 7 μm and less than 15 μm.
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