[SUMMARY] [OBJECT] To accurately estimate deterioration of various kinds of secondary batteries, and accurately estimate the deterioration of the secondary battery even when there is a variation among cells. [ORGANIZATION] A secondary battery deterioration estimation device 1 estimating deterioration of a secondary battery 14 includes: a finding unit (CPU 10a) which finds components forming an equivalent circuit of the secondary battery; a storage unit (RAM 10c) which stores history of a use state of the secondary battery; and an estimation unit (CPU 10a) which estimates a deterioration state of the secondary battery based on the components forming the equivalent circuit, wherein the estimation unit corrects an estimation process or an estimation result by the components forming the equivalent circuit based on the history of the use state stored in the storage unit.
展开▼
