Patent ID: 9343751
Filing Date: 2016-05-17
CPC Classification: H01M,Y02E,Y02P

Claim Text:
1. A porous electrode substrate having a three-dimensional entangled structure, the porous electrode substrate comprises short carbon fibers (A) having a length of from 2 to 12 mm dispersed in the three-dimensional structure which are joined together via three-dimensional mesh-like carbon fibers (B), wherein the porous electrode substrate is produced by the method comprising: (1) producing a precursor sheet X-1 comprising (i) short carbon fibers (A) having a length of from 2 to 12 mm and (ii) at least one fiber selected from the group consisting of short carbon fiber precursors (b) having a length of from 2 to 20 mm and fibrillar carbon fiber precursors (b′) dispersed in a two-dimensional plane; (2) subjecting the precursor sheet X-1 obtained in (1) to entanglement treatment, thereby three-dimensionally orienting the short carbon fibers (A) and providing a three-dimensional entangled porous electrode substrate precursor sheet X-2; and (3) subjecting the three-dimensional entangled porous electrode substrate precursor sheet X-2 to carbonization treatment at a temperature of 1000° C. or higher, thereby producing the porous electrode substrate, wherein the entanglement treatment is carried out by at least one method selected from the group consisting of a needle punching method, a water jet punching method, and a stream jet punching method.