Battery control system
A battery control system including a secondary battery within which gas is generated with use, and a controller configured to control charging/discharging of the secondary battery. In the controller, a measurer is configured to measure a resistance of the secondary battery, and a stop director is configured to stop charging/discharging of the secondary battery when the resistance of the secondary battery has exceeded a predetermined resistance threshold.
1. A battery control system comprising:
a secondary battery within which gas is generated with use, the secondary battery including a valve that opens in response to internal pressure reaching an opening pressure; and
a controller configured to control charging/discharging of the secondary battery, the controller comprising:
a measurer configured to measure an internal resistance of the secondary battery that has degraded with use; and
a stop director configured to stop charging/discharging of the secondary battery when the internal resistance of the secondary battery has exceeded a predetermined resistance threshold, wherein
the internal pressure of the secondary battery is an increasing function of the internal resistance of the secondary battery, and
the internal pressure of the secondary battery corresponding to the predetermined resistance threshold is less than the opening pressure.
2. The battery control system according to claim 1 , wherein
the controller further comprises an input calculator configured to calculate the internal resistance threshold using information regarding a temperature and a state of charge of the secondary battery under a use circumstance, the information being externally input.
3. The battery control system according to claim 1 , wherein
the controller further comprises:
a parameter measurer configured to measure at least one parameter of the secondary battery under a use circumstance; and
an automatic calculator configured to calculate the internal resistance threshold using a measurement of the at least one parameter.
4. The battery control system according to claim 3 , wherein
the parameter measurer is configured to regularly measure a temperature and a state of charge of the secondary battery as the at least one parameter, and
the automatic calculator is configured to acquire a representative value of temperature from a plurality of temperature measurements and a representative value of state of charge from a plurality of state of charge measurements, and using these representative values, calculate the internal resistance threshold.
5. The battery control system according to claim 4 , wherein
the parameter measurer is configured to regularly measure the temperature and the state of charge of the secondary battery for at least one year.
6. A battery control system comprising:
a secondary battery within which gas is generated with use, the secondary battery including a valve that opens in response to internal pressure reaching an opening pressure; and
a controller configured to control charging/discharging of the secondary battery, the controller comprising:
a measurer configured to measure an internal resistance and a capacity of the secondary battery that has degraded with use; and
a stop director configured to stop charging/discharging of the secondary battery, not only in response to a measurement of the internal resistance of the secondary battery exceeding a predetermined resistance threshold, but also in response to a measurement of the capacity of the secondary battery decreasing below a predetermined capacity threshold, wherein
the internal pressure of the secondary battery is an increasing function of the internal resistance of the secondary battery,
the internal pressure of the secondary battery corresponding to the predetermined resistance threshold is less than the opening pressure,
the internal pressure of the secondary battery is also a decreasing function of the capacity of the secondary battery, and
the internal pressure of the secondary battery corresponding to the predetermined capacity threshold is less than the opening pressure.
7. The battery control system according to claim 6 , wherein
the controller further comprises an input calculator configured to calculate the internal resistance threshold and the capacity threshold using information regarding a temperature and a state of charge of the secondary battery under a use circumstance, the information being externally input.
8. The battery control system according to claim 6 , wherein the controller further comprises:
a parameter measurer configured to measure at least one parameter of the secondary battery under a use circumstance; and
an automatic calculator configured to calculate the internal resistance threshold and the capacity threshold using a measurement of the at least one parameter.
9. The battery control system according to claim 8 , wherein
the parameter measurer is configured to regularly measure a temperature and a state of charge of the secondary battery as the at least one parameter, and
the automatic calculator is configured to acquire a representative value of temperature from a plurality of temperature measurements and a representative value of state of charge from a plurality of state of charge measurements, and using these representative values, calculate the internal resistance threshold and the capacity threshold.
10. The battery control system according to claim 9 , wherein
the parameter measurer is configured to regularly measure the temperature and the state of charge of the secondary battery for at least one year.