US 11,705,552 B2
Negative active material for rechargeable lithium battery and rechargeable lithium battery including same
Ji Woo Ahn, Yongin-si (KR); Dongwoo Kim, Yongin-si (KR); Jaehou Nah, Yongin-si (KR); Bumjin Chang, Yongin-si (KR); Yurim Cha, Yongin-si (KR); Yeonjoo Choi, Yongin-si (KR); and Ilyoung Choi, Yongin-si (KR)
Assigned to Samsung SDI Co., Ltd., Yongin-si (KR)
Appl. No. 16/312,972
Filed by Samsung SDI Co., Ltd., Yongin-si (KR)
PCT Filed Jul. 10, 2017, PCT No. PCT/KR2017/007348
§ 371(c)(1), (2) Date Dec. 21, 2018,
PCT Pub. No. WO2018/012821, PCT Pub. Date Jan. 18, 2018.
Claims priority of application No. 10-2016-0088888 (KR), filed on Jul. 13, 2016.
Prior Publication US 2019/0229325 A1, Jul. 25, 2019
Int. Cl. H01M 4/133 (2010.01); H01M 4/36 (2006.01); H01M 4/38 (2006.01); H01M 4/587 (2010.01)
CPC H01M 4/133 (2013.01) [H01M 4/366 (2013.01); H01M 4/386 (2013.01); H01M 4/387 (2013.01); H01M 4/587 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A negative active material for a rechargeable lithium battery, comprising:
a plurality of primary particles of a crystalline carbon-based material and a secondary particle, the secondary particle comprising a mixture of both an assembly of the primary particles and a binder pitch,
wherein the crystalline carbon-based material is a needle-cokes type artificial graphite,
wherein a ratio of an average particle diameter (D50) of the secondary particle relative to an average particle diameter (D50) of the primary particles ranges from 1.5 to 5,
an aspect ratio of the primary particles ranges from 1 to 5, and
wherein in an X-ray diffraction pattern of the negative active material, the I(002)/I(110) that is a ratio of X-ray diffraction intensities of the negative active material at a (002) plane and a (110) plane and a pellet density of the negative active material have a relationship of Equation 1:
29≤[(I(002)/I(110))/pellet density (cc/g)≤90.64,  [Equation 1]
wherein the average particle diameter (D50) of the primary particles ranges from 3 μm to 10 μm,
wherein in an X-ray diffraction pattern of the negative active material, I(002)/I(110) that is a ratio of X-ray diffraction intensities at a (002) plane and a (110) plane ranges from 50 to 270,
wherein the binder pitch is coal pitch and/or petroleum pitch, and
a weight ratio between the primary particles and the binder pitch of the negative active material for the rechargeable lithium battery is 5:5 to 9.9:0.1.