Panasonic Intellectual Property Management Co., Ltd.

Yusuke Itakura

Shinya Nishikawa

Changhui Yang

Tohru Watanabe

Takashi Iida

Yohei Ishii

In a management device that manages a power storage module in which a plurality of cell blocks in which a plurality of cells are connected in parallel are connected in series, a voltage detector detects a voltage of each of the plurality of cell blocks connected in series. The controller calculates a change value of a voltage of each of the plurality of cell blocks for a certain period of time, integrates absolute values of calculated voltage change values for each of the cell blocks, and determines presence or absence of a cell block including a separated cell that is electrically separated based on an integration value of voltage changes for each of the plurality of cell blocks.

Management device and power storage system

An acquisition unit of management unit acquires monitoring data including at least one of voltage and state of charge of a plurality of power storage packs connected in parallel. A switch controller can individually control on/off of a plurality of switches based on a voltage difference between the plurality of power storage packs or an SOC difference between the plurality of power storage packs. When calculating the entire capacity of the plurality of power storage packs, a capacity calculator also adds the capacity of power storage pack connected to a switch in an off state in a case where the switch can be controlled to an on state in future.

Management device, power supply system, electrically driven moving body, and management method

A controller executes an equalization process of equalizing capacities of a plurality of cells, and a cell abnormality determination process of, of detected voltages of the plurality of cells, calculating a voltage difference between a representative voltage based on the detected voltage of at least one cell to be compared and the detected voltage of one cell to be detected at a first time and a second time, and when a difference between the two voltage differences is greater than or equal to a threshold value, determining that the cell to be detected is abnormal. In the case of executing the cell abnormality determination process during the equalization process, the controller provides the detected voltage of a target cell to be subjected to the equalization process with a compensation value corresponding to a voltage change based on energy transfer in the target cell due to the equalization process between the first time and the second time, and calculates the voltage difference at the second time.

Management device and power supply system

Provided is a controller configured: to calculate, among voltages detected from a plurality of cells, a voltage difference between the voltage detected from one cell of the plurality of cells, the one cell to be detected, and a representative voltage at each of a first time and a second time, the representative voltage based on the voltage detected from at least one cell of the plurality of cells, the at least one cell to be compared; and when a discrepancy between the voltage difference at the first time and the voltage difference at the second time is equal to or more than a threshold, to determine that an abnormality has occurred in the one cell to be detected. The controller refers to a state-of-charge versus open-circuit-voltage (SOC-OCV) curve of the one cell to be detected in accordance with a state-of-health (SOH) of the one cell to be detected, so as to estimate an SOC as initial capacitance reference of the one cell to be detected in correspondence to the voltage detected from the one cell to be detected. The controller introduces a linear function using an SOC as initial capacitance reference as an input variable, using an OCV as an output variable, and having a predetermined inclination, and applies the SOC as initial capacitance reference of the one cell to be detected that the controller has estimated to the linear function, so as to derive an OCV. Then, in place of the voltage detected from the one cell to be detected, the controller uses the OCV that the controller has derived, so as to calculate the voltage difference at the first time and the voltage difference at the second time.

A smoothing unit smoothes a detected voltage of each power storage block based on previous data during a certain period. A calculator calculates a difference between a smoothing voltage of one power storage block in the n power storage blocks and a representative value of the smoothing voltages of the other power storage blocks or all the power storage blocks. A determination unit determines a power storage block whose difference against the representative value enlarges more than or equal to a set value during a predetermined period as a power storage block containing an abnormal power storage cell.

Growing community of inventors

Nara, Japan

Yusuke Itakura