US 12,385,981 B2
Battery monitoring device including calculation of impedance using independent electrical path to a response signal input
Masaaki Kitagawa, Kariya (JP)
Assigned to DENSO CORPORATION, Kariya (JP)
Filed by DENSO CORPORATION, Kariya (JP)
Filed on Oct. 26, 2021, as Appl. No. 17/510,851.
Application 17/510,851 is a continuation of application No. PCT/JP2020/017386, filed on Apr. 22, 2020.
Claims priority of application No. 2019-086141 (JP), filed on Apr. 26, 2019.
Prior Publication US 2022/0045544 A1, Feb. 10, 2022
Int. Cl. G01R 31/389 (2019.01); G01R 31/36 (2020.01); G01R 31/367 (2019.01); G01R 31/382 (2019.01); H01M 10/44 (2006.01); H01M 10/48 (2006.01); H02J 7/00 (2006.01); H02J 7/04 (2006.01)
CPC G01R 31/389 (2019.01) [G01R 31/3648 (2013.01); G01R 31/367 (2019.01); G01R 31/382 (2019.01); H01M 10/44 (2013.01); H01M 10/48 (2013.01); H02J 7/0013 (2013.01); H02J 7/0014 (2013.01); H02J 7/0016 (2013.01); H02J 7/0048 (2020.01); H02J 7/005 (2020.01); H02J 7/04 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A battery monitoring device for monitoring a state of a rechargeable battery that includes an electrolyte and a plurality of electrodes, comprising:
a signal control unit configured to instruct emission of a predefined AC signal;
a response signal input unit configured to receive a response signal of the rechargeable battery to the AC signal;
a calculation unit configured to calculate a complex impedance of the rechargeable battery based on the response signal; and
a power supply unit configured to receive a power supply voltage from the rechargeable battery and supplies the power supply voltage to at least the calculation unit; and
a waveform instruction unit configured to output an instruction signal to indicate a waveform of the AC signal to the signal control unit,
wherein a first electrical path connecting the rechargeable battery to the power supply unit and a second electrical path connecting the rechargeable battery to the signal control unit are provided independent of each other,
the signal control unit is configured to cause the rechargeable battery to be monitored, as a power source, to output the predefined AC signal,
the signal control unit includes a switching unit configured to adjust an amount of current based on an instruction, a resistor connected in series with the switching unit, a current detection unit configured to detect a current flowing through the resistor, and an instruction unit configured to provide the instruction to the switching unit, the instruction unit being configured to provide the instruction to the switching unit so as to make a correction for errors in a detection signal detected by the current detection unit based on a comparison between the detection signal and the instruction signal,
the calculation unit is configured to perform dual phase lock-in detection to determine an amplitude and a phase of the detection signal based on a value calculated by multiplying the instruction signal indicated by the waveform instruction unit and the detection signal from the current detection unit, and a value calculated by multiplying a signal acquired by shifting a phase of the instruction signal by a predefined angle and the detection signal, and
the calculation unit is configured to calculate the complex impedance based on the response signal and a detection signal detected by the dual phase lock-in detection.