In this research, a fuel cell system is operated for 30 min and then stopped for 30 min, followed by re-operation for another 30 min to examine its restart characteristics. In this way, potential hybrid power sources, such as solar cells, can be utilized during the inoperational mode of fuel cell systems. However, such operation shows that the concentration of sodium hydroxide in sodium borohydride solutions and the durability of Co-P/Ni foam catalysts play important roles in restarting the proton exchange membrane fuel cell after the 30-min break. Thus, this article describes the catalytic hydrolysis performance of NaBH4 solutions and the operation of PEM fuel cells to characterize the discontinuous mode of fuel cell systems. Moreover, the byproduct is removed from the byproduct storage while operating the fuel cell system, reducing the total system's weight.