US 11,955,834 B2
Backup power supply device and method for charging and discharging the same
Shunichiro Sugimori, Tokyo (JP); and Naoaki Konda, Tokyo (JP)
Assigned to FDK CORPORATION, Tokyo (JP)
Filed by FDK CORPORATION, Tokyo (JP)
Filed on Oct. 28, 2022, as Appl. No. 18/050,942.
Claims priority of application No. 2021-189344 (JP), filed on Nov. 22, 2021.
Prior Publication US 2023/0163624 A1, May 25, 2023
Int. Cl. H02J 9/06 (2006.01); H02J 7/00 (2006.01)
CPC H02J 9/061 (2013.01) [H02J 7/0013 (2013.01); H02J 7/007182 (2020.01)] 12 Claims
OG exemplary drawing
 
1. A backup power supply device to be connected to a conduction path from an external power supply to an external load, comprising:
a plurality of secondary batteries connected in parallel;
a plurality of charging switches capable of individually passing and cutting off charging power to be supplied from the conduction path to the plurality of secondary batteries; and
a control device for performing discharging control of the plurality of secondary batteries when a power supply voltage of the conduction path drops below a predetermined power failure detection threshold value, wherein when battery voltages of the plurality of secondary batteries drop below a predetermined charging start threshold value, the control device performs charging control with a time difference set between charging start timings of the secondary batteries.