Effect of current collector corrosion made from printed circuit board (PCB) on the degradation of self-breathing direct methanol fuel cell stack

Adopting printed circuit board (PCB) as the current collector for direct methanol fuel cell (DMFC) is a promising task. This paper found that the combinational 10 μm Ni/2 μm Au coatings on PCB could not endure halide attacking in its anodic polarization. With this coated PCB, the self-breathing DMFC stack with passive methanol supply exhibited progressively degradation in its lifetime test. By using a series of measurements, it is shown that initial corrosion would not obviously influence stack degradation, but the subsequently inter-facilitation, between F⁻ originating from Nafion membrane and corrosion products of Ni²⁺ and Cu²⁺ from PCB, would result in serious degradation, the final stack invalidation would present accompanied with the loss of membrane conductivity. The defects on coated PCB are crucial to initiate localized corrosion and stack degradation. Although cyclic voltammetry (CV) technology is effective to recover cell temporarily, its damage by releasing F⁻ should be further evaluated.