US 12,170,362 B2
Negative electrode for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery
Kaori Ishikawa, Hyogo (JP); Yuta Matsuo, Hyogo (JP); Daisuke Ito, Hyogo (JP); and Kouhei Tsuzuki, Hyogo (JP)
Assigned to PANASONIC HOLDINGS CORPORATION, Osaka (JP); and PANASONIC ENERGY CO., LTD., Osaka (JP)
Appl. No. 16/640,216
Filed by Panasonic Corporation, Kadoma (JP); and SANYO Electric Co., Ltd., Daito (JP)
PCT Filed Dec. 14, 2018, PCT No. PCT/JP2018/046008
§ 371(c)(1), (2) Date Feb. 19, 2020,
PCT Pub. No. WO2019/131195, PCT Pub. Date Jul. 4, 2019.
Claims priority of application No. 2017-252477 (JP), filed on Dec. 27, 2017.
Prior Publication US 2020/0365878 A1, Nov. 19, 2020
This patent is subject to a terminal disclaimer.
Int. Cl. H01M 4/36 (2006.01); H01M 4/02 (2006.01); H01M 4/133 (2010.01); H01M 4/134 (2010.01); H01M 4/66 (2006.01); H01M 10/0525 (2010.01)
CPC H01M 4/364 (2013.01) [H01M 4/133 (2013.01); H01M 4/134 (2013.01); H01M 4/366 (2013.01); H01M 4/661 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A negative electrode for a nonaqueous electrolyte secondary battery, the negative electrode comprising a negative electrode current collector and a negative electrode mixture layer formed on the negative electrode current collector,
the negative electrode mixture layer including
a first layer formed on the negative electrode current collector and including a negative electrode active material and a first binding agent, the negative electrode active material, which is in the first layer, including a carbon material A and a Si-containing compound, the first binding agent including polyacrylic acid or a salt thereof, and
a second layer formed on the first layer and including a negative electrode active material and a second binding agent, the negative electrode active material, which is in the second layer, including a carbon material B, the carbon material B having a tap density higher than a tap density of the carbon material A, wherein
a mass of the first layer relative to a mass of the negative electrode mixture layer is 50 mass % or greater and less than 90 mass %, and a mass of the second layer relative to the mass of the negative electrode mixture layer is greater than 10 mass % and 50 mass % or less,
a packing density of the second layer is lower than a packing density of the first layer,
a mass ratio between the carbon material A and the Si-containing compound in the first layer is within a range of 95:5 to 70:30, and
a concentration of the first binding agent in the first layer is higher than a concentration of the second binding agent in the second layer.