Secondary battery diagnostic device
A diagnostic device for a secondary battery which is an all-solid-state battery containing a solid electrolyte transporting lithium ions, in which the diagnostic device includes: an interruption means configured to interrupt a charging current or a discharging current of the secondary battery connected to a circuit; a measuring means configured to measure over time a variation characteristic of a terminal voltage of the secondary battery after the current is interrupted by the interruption means; and a diagnostic means configured to diagnose the cause of the degradation of the secondary battery by comparing a change rate or a change amount in voltage between a charging characteristic specified from measured values of a terminal voltage of the secondary battery measured by the measuring means, a charging/discharging characteristic specified from the measured values of the terminal voltage measured by the measuring means, and a reference characteristic of the secondary battery.
1. A secondary battery diagnostic device comprising:
an interruption means configured to interrupt a charging current or a discharging current of a secondary battery connected to a charging circuit or a discharging circuit;
a measuring means configured to measure over time a variation characteristic of a terminal voltage of the secondary battery after the charging current or the discharging current is interrupted by the interruption means; and
a diagnostic means configured to diagnose a cause of degradation of the secondary battery distinguishing between electrode degradation and electrolyte degradation by comparing a change rate or a change amount in voltage between a charging/discharging characteristic specified from a measured value of the terminal voltage of the secondary battery measured by the measuring means and a reference characteristic of the secondary battery based on an initial value.
2. The secondary battery diagnostic device according to claim 1 , wherein the secondary battery is an all-solid-state battery containing a solid electrolyte transporting a lithium ion.
3. The secondary battery diagnostic device according to claim 1 , wherein the diagnostic means is configured to compare a change rate in voltage between the charging/discharging characteristic specified from the measured value of the terminal voltage of the secondary battery and the reference characteristic of the secondary battery based on the initial value, and in a case in which the diagnostic means determines that the change rate in voltage immediately after the current interruption is lower than the change rate in voltage indicated by the reference characteristic, the diagnostic means is configured to diagnose that the cause of the degradation of the secondary battery under diagnosis is due to electrode degradation of the secondary battery.
4. A secondary battery diagnostic device comprising:
an interruption means configured to interrupt a charging current or a discharging current of a secondary battery connected to a charging circuit or a discharging circuit;
a measuring means configured to measure over time a variation characteristic of a terminal voltage of the secondary battery after the charging current or the discharging current is interrupted by the interruption means; and
a diagnostic means configured to diagnose a cause of degradation of the secondary battery by comparing a change rate or a change amount in voltage between a charging/discharging characteristic specified from a measured value of the terminal voltage of the secondary battery measured by the measuring means and a reference characteristic of the secondary battery based on an initial value,
wherein the diagnostic means is configured to compare the charging/discharging characteristic specified from the measured value of the terminal voltage of the secondary battery, the reference characteristic of the secondary battery, and a change rate in voltage variation in a range of 0.1 to 600 sec immediately after the current interruption, and in a case in which the diagnostic means determines that a change rate in voltage immediately after the current interruption is lower than a change rate in voltage indicated by the reference characteristic, the diagnostic means is configured to diagnose that the cause of the degradation of the secondary battery under diagnosis is due to electrode degradation of the secondary battery.
5. A secondary battery diagnostic device comprising:
an interruption means configured to interrupt a charging current or a discharging current of a secondary battery connected to a charging circuit or a discharging circuit;
a measuring means configured to measure over time a variation characteristic of a terminal voltage of the secondary battery after the charging current or the discharging current is interrupted by the interruption means; and
a diagnostic means configured to diagnose a cause of degradation of the secondary battery by comparing a change rate or a change amount in voltage between a charging/discharging characteristic specified from a measured value of the terminal voltage of the secondary battery measured by the measuring means and a reference characteristic of the secondary battery based on an initial value,
wherein the diagnostic means is configured to diagnose that the cause of the degradation of the secondary battery under diagnosis is due to electrolyte degradation in a case in which the diagnostic means determines that a change amount in a range of 0 to 0.1 sec is larger than a change amount indicated by the reference characteristic, in relation to voltage variation immediately after the current interruption of voltage, between the charging/discharging characteristic specified from the measured value of the terminal voltage of the secondary battery, and the reference characteristic of the secondary battery based on an initial value.
6. The secondary battery diagnostic device according to claim 1 , wherein in a case in which the diagnostic means diagnoses that the cause of the degradation of the secondary battery under diagnosis is due to electrode degradation of the secondary battery, the charging circuit does not execute quick charging to the secondary battery.
7. The secondary battery diagnostic device according to claim 2 , wherein in a case in which the diagnostic means diagnoses that the cause of the degradation of the secondary battery under diagnosis is due to electrode degradation of the secondary battery, the charging circuit does not execute quick charging to the secondary battery.
8. The secondary battery diagnostic device according to claim 3 , wherein in a case in which the diagnostic means diagnoses that the cause of the degradation of the secondary battery under diagnosis is due to the electrode degradation of the secondary battery, the charging circuit does not execute quick charging to the secondary battery.
9. The secondary battery diagnostic device according to claim 4 , wherein in a case in which the diagnostic means diagnoses that the cause of the degradation of the secondary battery under diagnosis is due to the electrode degradation of the secondary battery, the charging circuit does not execute quick charging to the secondary battery.
10. The secondary battery diagnostic device according to claim 1 , wherein the secondary battery is a lithium-ion battery.
11. The secondary battery diagnostic device according to claim 2 , wherein the secondary battery is a lithium-ion battery.
12. The secondary battery diagnostic device according to claim 3 , wherein the secondary battery is a lithium-ion battery.
13. The secondary battery diagnostic device according to claim 4 , wherein the secondary battery is a lithium-ion battery.
14. The secondary battery diagnostic device according to claim 5 , wherein the secondary battery is a lithium-ion battery.
15. The secondary battery diagnostic device according to claim 6 , wherein the secondary battery is a lithium-ion battery.
16. The secondary battery diagnostic device according to claim 7 , wherein the secondary battery is a lithium-ion battery.
17. The secondary battery diagnostic device according to claim 8 , wherein the secondary battery is a lithium-ion battery.
18. The secondary battery diagnostic device according to claim 9 , wherein the secondary battery is a lithium-ion battery.