Abstract: A temperature elevating apparatus of a secondary battery includes a ripple generator and a controller. Ripple generator is connected to secondary battery, and is configured to actively generate ripple current of a predetermined frequency in secondary battery. Controller controls ripple generator to elevate a temperature of the secondary battery by generating ripple current in secondary battery. Here, the predetermined frequency is set to be a frequency in a frequency region where an absolute value of an impedance of secondary battery relatively decreases based on frequency characteristics of the impedance of secondary battery.

Abstract: An alternating current impedance-estimating section (106) estimates an alternating current impedance (Rh) of the secondary battery based on electric current (I) and voltage (V) of the secondary battery detected when a ripple generating section causes a ripple current to flow in the secondary battery. A temperature estimating section (108) estimates the temperature (T) of the secondary battery based on the alternating current impedance (Rh) estimated by the alternating current impedance-estimating section (106) with the use of the relation, obtained in advance, between the temperature (T) of the secondary battery and the alternating current impedance (Rh) of the secondary battery at a ripple frequency.

Abstract: A first calculating section (118) calculates an allowable output power (WoutA) of the secondary battery before a ripple temperature increase operation for increasing the temperature of a secondary battery by causing a ripple current to flow in the secondary battery is performed, the allowable output power being determined in advance based on the temperature and a state of charge (SOC) of the secondary battery. A second calculating section (120) calculates the allowable output power (WoutB) achieved when the ripple temperature increase operation is performed. A determining section (122) determines whether to perform the ripple temperature increase operation so that when the allowable output power (WoutB) is equal to or greater than the allowable output power (WoutA), the ripple temperature increase operation is performed and, when the allowable output power (WoutB) is smaller than the allowable output power (WoutA), the ripple temperature increase operation is not performed.

Abstract: An ECU determines whether the ripple current is within a target range (S50). When it is determined that the ripple current is not within the target range (NO in S50), the ECU determines whether the ripple current is greater than or less than the target range (S80). When it is determined that the ripple current is less than the target range (NO in S80), the ECU reduces the carrier frequency of the boost converter that is a component of the ripple generating section (S90). On the other hand, when it is determined that the ripple current is greater than the target range (YES in S80), the ECU increases the carrier frequency of the boost converter (S100).

Abstract: A first calculating section (118) calculates an allowable output power (WoutA) of the secondary battery before a ripple temperature increase operation for increasing the temperature of a secondary battery by causing a ripple current to flow in the secondary battery is performed, the allowable output power being determined in advance based on the temperature and a state of charge (SOC) of the secondary battery. A second calculating section (120) calculates the allowable output power (WoutB) achieved when the ripple temperature increase operation is performed. A determining section (122) determines whether to perform the ripple temperature increase operation so that when the allowable output power (WoutB) is equal to or greater than the allowable output power (WoutA), the ripple temperature increase operation is performed and, when the allowable output power (WoutB) is smaller than the allowable output power (WoutA), the ripple temperature increase operation is not performed.

Abstract: An ECU determines whether the ripple current is within a target range (S50). When it is determined that the ripple current is not within the target range (NO in S50), the ECU determines whether the ripple current is greater than or less than the target range (S80). When it is determined that the ripple current is less than the target range (NO in S80), the ECU reduces the carrier frequency of the boost converter that is a component of the ripple generating section (S90). On the other hand, when it is determined that the ripple current is greater than the target range (YES in S80), the ECU increases the carrier frequency of the boost converter (S100).

Abstract: An alternating current impedance-estimating section (106) estimates an alternating current impedance (Rh) of the secondary battery based on electric current (I) and voltage (V) of the secondary battery detected when a ripple generating section causes a ripple current to flow in the secondary battery. A temperature estimating section (108) estimates the temperature (T) of the secondary battery based on the alternating current impedance (Rh) estimated by the alternating current impedance-estimating section (106) with the use of the relation, obtained in advance, between the temperature (T) of the secondary battery and the alternating current impedance (Rh) of the secondary battery at a ripple frequency.

Abstract: A temperature elevating apparatus of a secondary battery (10) includes a ripple generator (20) and a controller (30). Ripple generator (20) is connected to secondary battery (10), and is configured to actively generate ripple current (I) of a predetermined frequency in secondary battery (10). Controller (30) controls ripple generator (20) to elevate a temperature of the secondary battery by generating ripple current (I) in secondary battery (10). Here, the predetermined frequency is set to be a frequency in a frequency region where an absolute value of an impedance of secondary battery (10) relatively decreases based on frequency characteristics of the impedance of secondary battery (10).