Abstract: For the verification of the electrical safety of nuclear power plants when seismic external events occur, it is required to conduct the seismic qualification test for the storage batteries. In this paper, with the seismic qualification test data and engineering experience of the storage batteries, we focus on the Class 1E storage batteries of high temperature gas-cooled reactor (HTR). The identification and the quantification of the fragility variables are then made for fragility curves and the high confidence of low probability of failure (HCLPF) capacity through the methods of fragility computations based on dynamic testing. The results show that the HCLPF capacity of uninterrupted power system Class 1E storage batteries are much higher than the design basis earthquake level of HTR.