CPC H01M 4/366 (2013.01) [H01M 4/0404 (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)] | 17 Claims |
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, and the negative electrode film comprises a first negative electrode film and a second negative electrode film;
the first negative electrode film is disposed on at least one surface of the negative electrode current collector and comprises a first negative electrode active material;
the second negative electrode film is disposed on the first negative electrode film and comprises a second negative electrode active material,
the first negative electrode active material comprises natural graphite and satisfies: 0.60≤S1≤0.74, where S1=W2H/(W3R+W2H);
the second negative electrode active material comprises artificial graphite,
the first negative electrode film is thicker than the second negative electrode film, and
a thickness ratio of the first negative electrode film to the second negative electrode film is from 1:1.01 to 1:1.1,
in which W3R is a peak area of 101 crystal plane in a X-ray diffraction spectrum of the first negative electrode active material at a diffraction angle of 43.3±0.05°, and W2H is a peak area of 101 crystal plane in a X-ray diffraction spectrum of the first negative electrode active material at a diffraction angle of 44.5±0.05°.
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