Current collector for air electrode

Abstract

The invention relates to a current collector for an air electrode. The current collector comprises foam carbon. As the slurry can be uniformly coated on the foam carbon, the amount of the carbon material, the catalyst and the like loaded on the current collector can be properly reduced, and the coating thickness can be reduced, so that the utilization rate of the catalyst and the like is greatly increased, the transportation of oxygen in the air electrode is facilitated, and finally, the purposes of improving the discharge capacity and reducing the discharge cost are achieved. Polarization isreduced and power characteristics are improved.

Description

technical field [0001] The invention belongs to the field of air batteries, in particular to a current collector for an air electrode. Background technique [0002] The air electrode is a thin electrode widely used in various air batteries, one side is in contact with the electrolyte and the other side is in contact with the air. During the discharge process of the battery, the air electrode is used as the cathode, oxygen diffuses along the surface of the electrode into the interior of the electrode, and a reduction reaction occurs under the action of the catalyst. For secondary batteries, the oxygen electrode acts as an anode during charging, and an oxygen evolution reaction occurs on the electrode surface. The air electrode is the reaction site of oxygen, which has the functions of breathability, conductivity, waterproof, corrosion resistance and catalysis. [0003] The air electrode is a hydrophobic gas diffusion electrode, which is composed of a hydrophobic gas permeab...

AI Technical Summary

Problems solved by technology

However, the pore size of foamed nickel is relatively large (200-500 μm), and the distribution of pores is relatively sparse, which causes great difficulties in the coating of slurry.

Its sparse and large pore structure makes it difficult for the slurry to evenly cover the entire surface of the air electrode, so that the carbon materials and catalysts in the dried air electrode are easy to accumulate together or even form large blocks, which significantly inhibits the electrode. Material transport during the chemical reaction, the available active sites are reduced, resulting in low utilization of materials, and at the same time, the overpotential of the battery is increased and the power characteristics are reduced