US 11,750,006 B2
Estimation system and estimation method
Yoshiki Sugino, Seto (JP); Kimihito Nakamura, Toyota (JP); and Masanari Ishikawa, Toyota (JP)
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed by TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed on Aug. 21, 2020, as Appl. No. 16/999,650.
Claims priority of application No. 2019-207193 (JP), filed on Nov. 15, 2019.
Prior Publication US 2021/0152002 A1, May 20, 2021
Int. Cl. H02J 7/00 (2006.01)
CPC H02J 7/0049 (2020.01) [H02J 7/00302 (2020.01); H02J 7/00716 (2020.01); H02J 7/007182 (2020.01)] 10 Claims
OG exemplary drawing
 
1. An estimation system, comprising:
a memory;
a secondary battery configured to be charged using electric power supplied from an external power source;
a monitoring device configured to detect a voltage and a current of the secondary battery; and
a processor programmed to estimate a full charge capacity of the secondary battery using a detection result of the monitoring device, wherein the processor is programmed to:
retrieve a previously estimated full charge capacity of the secondary battery determined from a previous charge cycle that is stored in the memory;
calculate a first charging rate of the secondary battery using a current integration amount in charging, discharging, or charging and discharging of the secondary battery and using the previously estimated full charge capacity of the secondary battery;
calculate a second charging rate of the secondary battery using an open circuit voltage of the secondary battery, when a predetermined time has elapsed without charging and discharging after the first charging rate is calculated; and
perform correction, when a magnitude of a difference between the first charging rate and the second charging rate is larger than a threshold, on the full charge capacity based on the difference.