| 摘要 |
PROBLEM TO BE SOLVED: To easily implement deterioration diagnosis of a storage battery in a power storage system.SOLUTION: A power storage system 100 comprises: a storage battery group 200 composed of a plurality of strings 201 to 204 installed in parallel with each other; and a control device 300 for charging the storage battery group by a photovoltaic power generation or the like, and supplying power to a load 4 by discharge. The control device 300 selects one string of a deterioration diagnosis target from the plurality of strings; makes at least one storage battery composing the string be, for example, in a full charge state while imposing discharge on the remaining strings; makes the storage battery having been in a full charge state be discharged to, for example, a complete discharge while restraining the storage battery from being charged during the discharge, while imposing charge from an external power supply on the remaining strings; calculates battery capacity actually released from the storage battery through the discharge to the complete discharge; and diagnoses the degree of deterioration by comparing the battery capacity with a predetermined value. |
