Abstract:

The influence of reaction conditions on the performance of a unit cell of unitized regenerative fuel cell（URFC）was reported. The cycling performance and polarization curves of the unit cell of URFC in the hydrogen and oxygen fuel cell and water electrolysis modes were tested. The unit cell of URFC exhibited excellent performance and stability in cycling test during URFC operation. The results showed that the optimum reaction temperature was from 60 ℃ to 70 ℃ in both fuel cell and water electrolysis modes. In fuel cell mode，increasing oxygen pressure would improve remarkably the performance of URFC. At hydrogen relative humidity of 100%，oxygen relative humidity had less influence on the performance of URFC in fuel cell mode. The performance of the unit cell by oxygen without humidifying was identical to that of the unit cell by oxygen relative humidity of 100% in fuel cell mode when current density was greater than 500 mA/cm².