ELECTRICITY STORAGE SYSTEM

摘要

[Problem] To determine the operation state of a current breaker. [Solution] The states of a plurality of electricity storage blocks connected in series are determined, each of said electricity storage blocks having a plurality of electricity storage elements connected in parallel. Each of the electricity storage elements has a current breaker that interrupts the current path of each of the electricity storage elements. When first voltage characteristics are deviated from second voltage characteristics, it is determined that the current breaker is operating. The first voltage characteristics are acquired from a voltage sensor for acquiring open voltages of the electricity storage blocks, and the first voltage characteristics indicate changes of the open voltages with respect to the capacities of the electricity storage blocks. The second voltage characteristics are calculated on the basis of capacity maintenance rate and capacity change quantities, and the second voltage characteristics indicate changes of the open voltages with respect to the capacities of the electricity storage blocks.