| 摘要 |
PROBLEM TO BE SOLVED: To solve such a problem of a lithium ion secondary battery using a two-phase coexistence positive electrode active material, that the resistance (internal resistance) of the secondary battery changes depending on the electrification state of current and immediately before.SOLUTION: A battery system has a lithium ion secondary battery (11) using a two-phase coexistence positive electrode active material, and a controller (40) for estimating the internal resistance of the lithium ion secondary battery. When the SOC of the lithium ion secondary battery falls within a SOC range of two-phase coexistence state, the controller estimates the internal resistance when the electrification state of current and immediately before does not change higher than the internal resistance when the electrification state of current and immediately before changes between the state of charge and the state of discharge. |
