▎ 摘　　要

NOVELTY - Bonding agent, comprises imide polymer, first conductive fiber, second conductive fiber and conductive particles, where the first conductive fiber has a reactive group, and the reactive group chemically reacts with the imide polymer to form a chemical bond, the average diameter of the second conductive fiber is ≮ 0.3 μm, and the average length of the second conductive fiber is ≮ 10 μm. USE - The bonding agent is useful in electrode pole piece for a secondary battery (all claimed). ADVANTAGE - The bonding agent efficiently reduces resistance of the electrode pole piece, improves conductivity of the electrode pole piece, improves cracking problem of the thick electrode pole piece, increases coating surface density of the electrode pole piece, and increases the energy density of the battery. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: Preparing bonding agent, comprising (a) reacting imide polymer precursor with first conductive fiber to obtain a conductive composite of the imide polymer and the first conductive fiber, (b) adding conductive particles to the conductive composite and dispersing evenly to obtain a dispersion of the composite and conductive particles, and (c) adding second conductive fiber to the dispersion, and dispersing evenly to obtain the bonding agent; Electrode pole piece, comprising a current collector and an electrode membrane coated on the surface of the current collector, where the electrode membrane contains the bonding agent; and Secondary battery, comprising anode piece, cathode piece, separator and an electrolyte, where the anode piece and/or the cathode piece is the electrode pole piece.