US 12,451,714 B2
Power storage device and method for operating power storage device
Kei Takahashi, Isehara (JP); Takayuki Ikeda, Atsugi (JP); Takanori Matsuzaki, Atsugi (JP); Munehiro Kozuma, Atsugi (JP); Hiroki Inoue, Atsugi (JP); Ryota Tajima, Isehara (JP); Yohei Momma, Isehara (JP); Mayumi Mikami, Atsugi (JP); Kazutaka Kuriki, Ebina (JP); and Shunpei Yamazaki, Setagaya (JP)
Assigned to Semiconductor Energy Laboratory Co., Ltd., Atsugi (JP)
Appl. No. 17/286,088
Filed by Semiconductor Energy Laboratory Co., Ltd., Atsugi (JP)
PCT Filed Oct. 16, 2019, PCT No. PCT/IB2019/058799
§ 371(c)(1), (2) Date Apr. 16, 2021,
PCT Pub. No. WO2020/084398, PCT Pub. Date Apr. 30, 2020.
Claims priority of application No. 2018-200834 (JP), filed on Oct. 25, 2018.
Prior Publication US 2021/0384751 A1, Dec. 9, 2021
Int. Cl. H02J 7/00 (2006.01); H10B 12/00 (2023.01); H10B 41/70 (2023.01); H10B 99/00 (2023.01)
CPC H02J 7/00712 (2020.01) [H02J 7/0029 (2013.01); H02J 7/0071 (2020.01); H10B 12/00 (2023.02)] 10 Claims
OG exemplary drawing
 
1. A method for operating a power storage device comprising a secondary battery, a control circuit configured to control a charging of the secondary battery, a reference generating circuit, and a timer circuit comprising a comparator, the method comprising:
generating a reference voltage and a reference current corresponding to a reference time of charging in the reference generating circuit in advance of charging;
supplying the reference voltage and the reference current from the reference generating circuit to the timer circuit, wherein the reference voltage is supplied to one of a non-inverting input terminal and an inverting input terminal of the comparator;
starting the charging of the secondary battery and supplying a first signal to inform that the charging of the secondary battery is started, wherein the first signal is supplied from the control circuit to the timer circuit;
generating a voltage corresponding to an elapsed time from when the charging of the secondary battery was started and supplying the voltage to the other one of the non-inverting input terminal and the inverting input terminal of the comparator; and
giving a warning to a user and stopping the charging of the secondary battery when the voltage corresponding to the elapsed time exceeds the reference voltage corresponding to the reference time of charging in the reference generating circuit.