	US 11,942,666 B2
	Precursor sheet for fuel cell separator, and fuel cell separator
Tomoyuki Araki, Chiba (JP); Miho Iwai, Chiba (JP); Takehiro Okei, Chiba (JP); and Kosuke Yasuda, Chiba (JP)
Assigned to NISSHINBO CHEMICAL INC., Tokyo (JP)
Appl. No. 18/273,624
Filed by NISSHINBO CHEMICAL INC., Tokyo (JP)
PCT Filed Nov. 30, 2022, PCT No. PCT/JP2022/044104 § 371(c)(1), (2) Date Jul. 21, 2023, PCT Pub. No. WO2023/120065, PCT Pub. Date Jun. 29, 2023.
Claims priority of application No. 2021-205641 (JP), filed on Dec. 20, 2021.
Prior Publication US 2024/0047705 A1, Feb. 8, 2024
Int. Cl. H01M 8/02 (2016.01); H01M 8/0234 (2016.01); H01M 8/0239 (2016.01); H01M 8/0245 (2016.01)

CPC H01M 8/0245 (2013.01) [H01M 8/0234 (2013.01); H01M 8/0239 (2013.01)]

22 Claims

1. A precursor sheet for fuel cell separator comprising:

an electroconductive substrate sheet, a dense layer containing first graphite particles, and an electroconductive layer containing second graphite particles,

wherein the dense layer and the electroconductive layer contain a resin,

the first graphite particles have a bulk density of 1.7 g/cm³or more and a volume resistivity of 20 mΩ·cm or more when compressed at 30 MPa, and

the second graphite particles have a bulk density of 1.5 g/cm³or more and a volume resistivity of less than 20 mΩ·cm when compressed at 30 MPa.