US 12,218,351 B2
Positive electrode active material for nonaqueous electrolyte secondary battery
Atsushi Ogawa, Wako (JP); Soshi Kawamura, Wako (JP); Toru Sukigara, Wako (JP); Hiroto Maeyama, Wako (JP); and Kenichi Kobayashi, Tokushima (JP)
Assigned to HONDA MOTOR CO., LTD., Tokyo (JP); and NICHIA CORPORATION, Anan (JP)
Filed by HONDA MOTOR CO., LTD., Tokyo (JP); and NICHIA CORPORATION, Anan (JP)
Filed on Sep. 26, 2023, as Appl. No. 18/474,436.
Application 18/474,436 is a continuation of application No. 17/828,438, filed on May 31, 2022, granted, now 11,804,600.
Application 17/828,438 is a continuation of application No. 16/808,525, filed on Mar. 4, 2020, granted, now 11,380,892, issued on Jul. 5, 2022.
Application 16/808,525 is a continuation of application No. 15/474,735, filed on Mar. 30, 2017, granted, now 10,622,629, issued on Apr. 14, 2020.
Claims priority of application No. 2016-072436 (JP), filed on Mar. 31, 2016; and application No. 2017-059661 (JP), filed on Mar. 24, 2017.
Prior Publication US 2024/0021816 A1, Jan. 18, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H01M 4/525 (2010.01); C01G 53/00 (2006.01); H01M 4/36 (2006.01); H01M 4/505 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/525 (2013.01) [C01G 53/42 (2013.01); C01G 53/50 (2013.01); H01M 4/366 (2013.01); H01M 4/505 (2013.01); C01P 2002/20 (2013.01); C01P 2002/50 (2013.01); C01P 2002/52 (2013.01); C01P 2004/03 (2013.01); C01P 2004/51 (2013.01); C01P 2004/61 (2013.01); C01P 2006/40 (2013.01); H01M 2004/021 (2013.01); H01M 2004/028 (2013.01); H01M 2220/20 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A positive electrode active material for a nonaqueous electrolyte secondary battery, comprising particles of a lithium-transition metal composite oxide that contains nickel in the composition thereof and has a layered structure, wherein
a ratio D50/DSEM of a 50% particle size D50 in volume-based cumulative particle size distribution to an average particle size DSEM based on electron microscopic observation is in a range of 1 to 4,
wherein the DSEM is to be determined as follows: observing an image at a magnification of 1,000 to 10,000 using a scanning electron microscope (SEM), selecting 100 particles having recognizable outlines, calculating the equivalent spherical diameters of the selected particles using an image processing software, and determining the arithmetic average of the obtained equivalent spherical diameters as DSEM; and
a ratio D90/D10 of a 90% particle size D90 to a 10% particle size D10 in volume-based cumulative particle size distribution is 4 or less.