Nec Corporation

Nec Energy Devices, Ltd.

Ngk Insulators, Inc.

Tokyo Electric Power Company Holdings, Inc.

Envision Aesc Energy Devices Ltd.

Yoichiro Tashiro

Shin Suzuki

Takayuki Shibata

Youko Kimura

Masataka Kurokawa

A storage battery system control method includes at least the following steps. Respective current SOC (state of charge) values of the large capacity storage battery system and the high power storage battery system are acquired. Electrical power, which is required to operate the frequency control service for the purpose of suppressing frequency fluctuations, to the large capacity storage battery system and the high power storage battery system, in accordance with the respective SOC values. The respectively allocated electrical power is charged or discharged by driving the large capacity storage battery system, or alternatively, the high power storage battery system, or alternatively, the large capacity storage battery system and the high power storage battery system.

Method for controlling storage battery system

A controller () reads out a voltage value correlated with the ambient temperature of a battery () measured by a temperature measurer () from a storage device (), so that a charger () charges the battery () at the voltage value read out by the controller ().

Charging apparatus

Remaining capacity calculation section () calculates remaining capacities for each of cells (-) and (-) connected in parallel with each other, and control section () discharges one of cells (-) and (-) having priority until the remaining capacity of that cell becomes equal to a second threshold value stored in storage section (), if the remaining capacity of the one of the cells calculated by remaining capacity calculation section () is equal to a first threshold value stored in storage section ().

Discharge controller

A battery sensing section measures a voltage across a secondary battery. A current sensing section measures a current flowing through the secondary battery. A control section holds the value of an external impedance present in a discharge path outside the secondary battery, discharges the secondary battery from a first time to a second time at which an integrated discharge capacity based on a measured discharge current becomes equal to a predetermined discharge capacity reference value, calculates the internal impedance present in the secondary battery at the second time based on the measured voltage, calculates the second open voltage at the second time by multiplying the sum of the external impedance and the internal impedance by the measured discharge current, and calculates the recovered capacity of the secondary battery based on the first open voltage at the first time, the second open voltage and the discharge capacity reference value.

Growing community of inventors

Tokyo, Japan

Yoichiro Tashiro