Information processing device, information processing method, computer program product, and information processing system

An information processing method executed by an information processing device, the information processing method comprising:

• measuring, by a monitoring unit of a battery, operation data of a battery;
• analyzing the operation data and calculating feature information indicating a feature of charging/discharging by the battery;
• selecting, in accordance with the feature information, an estimation method among a plurality of estimation methods for estimating a state of the battery from the operation data;
• estimating the state from the operation data using the selected estimation method;
• outputting, to a monitoring system, state information indicating the estimated state of the battery, the monitoring system monitoring and controlling operation of the battery based on the state information,
• wherein
• the operation data is time series data including measurement time, voltage, and current,
• the feature information includes:
• a mean ratio that is a ratio of a charging C-rate mean value that is a mean of C-rates during charging to a discharging C-rate mean value that is a mean of the C-rates during discharging, the C-rates being obtained by normalizing, by a rated power value, power values calculated by multiplying the voltage and the current;
• a data number ratio that is a ratio of a charging data number as a number of pieces of data of the C-rates during charging to a discharging data number as a number of pieces of data of the C-rates during discharging;
• and a switching ratio obtained by dividing a number of switchings between charging and discharging by a number of pieces of the operation data,
• the plurality of estimation methods include a first estimation method that estimates the state using magnitude of fluctuation in the voltage, a second estimation method that estimates the state using a difference between a mean value of the voltage during charging and a mean value of the voltage during discharging, and a third estimation method that estimates the state using a mean value of fluctuation in the voltage, and
• the selecting includes:
• selecting the first estimation method, when the switching ratio is greater than a first threshold,
• selecting the second estimation method, when the switching ratio is equal to or less than the first threshold, the data number ratio is outside a first specified range, and the mean ratio is outside a second specified range, and
• selecting the third estimation method, when the switching ratio is equal to or less than the first threshold, and the data number ratio is outside a within the first specified range or the mean ratio is outside a within the second specified range.

A computer program product comprising a non-transitory computer-readable medium including programmed instructions, the instructions causing a computer to execute:

• obtaining, via a network linked to a monitoring unit of a battery, operation data of the battery, the operation data being measured by the monitoring unit;
• analyzing the operation data and calculating feature information indicating a feature of charging/discharging by the battery;
• selecting, in accordance with the feature information, an estimation method among a plurality of estimation methods for estimating a state of the battery from the operation data;
• estimating the state from the operation data using the selected estimation method;
• and
• outputting, to a monitoring system, state information indicating the estimated state of the battery, the monitoring system monitoring and controlling operation of the battery based on the state information,
• wherein
• the operation data is time series data including measurement time, voltage, and current,
• the feature information includes:
• a mean ratio that is a ratio of a charging C-rate mean value that is a mean of C-rates during charging to a discharging C-rate mean value that is a mean of the C-rates during discharging, the C-rates being obtained by normalizing, by a rated power value, power values calculated by multiplying the voltage and the current;
• a data number ratio that is a ratio of a charging data number as a number of pieces of data of the C-rates during charging to a discharging data number as a number of pieces of data of the C-rates during discharging;
• and a switching ratio obtained by dividing a number of switchings between charging and discharging by a number of pieces of the operation data,
• the plurality of estimation methods include a first estimation method that estimates the state using magnitude of fluctuation in the voltage, a second estimation method that estimates the state using a difference between a mean value of the voltage during charging and a mean value of the voltage during discharging, and a third estimation method that estimates the state using a mean value of fluctuation in the voltage, and
• the selecting includes:
• selecting the first estimation method, when the switching ratio is greater than a first threshold,
• selecting the second estimation method, when the switching ratio is equal to or less than the first threshold, the data number ratio is outside a first specified range, and the mean ratio is outside a second specified range, and
• selecting the third estimation method, when the switching ratio is equal to or less than the first threshold, and the data number ratio is outside a within the first specified range or the mean ratio is outside a within the second specified range.

An information processing system comprising:

• a battery;
• a monitoring unit measuring operation data of the battery;
• a monitoring system monitoring and controlling operation of the battery;
• and
• one or more processors configured to:
• obtain, via a network linked to the monitoring unit, the operation data of the battery;
• analyze the operation data and calculate feature information indicating a feature of charging/discharging by the battery;
• select, in accordance with the feature information, an estimation method among a plurality of estimation methods for estimating a state of the battery from the operation data;
• estimate the state from the operation data using the selected estimation method;
• and
• output, to the monitoring system, state information indicating the estimated state of the battery, the monitoring system monitoring and controlling the operation of the battery based on the state information,
• wherein
• the operation data is time series data including measurement time, voltage, and current,
• the feature information includes:
• a mean ratio that is a ratio of a charging C-rate mean value that is a mean of C-rates during charging to a discharging C-rate mean value that is a mean of the C-rates during discharging, the C-rates being obtained by normalizing, by a rated power value, power values calculated by multiplying the voltage and the current;
• a data number ratio that is a ratio of a charging data number as a number of pieces of data of the C-rates during charging to a discharging data number as a number of pieces of data of the C-rates during discharging;
• and a switching ratio obtained by dividing a number of switchings between charging and discharging by a number of pieces of the operation data,
• the plurality of estimation methods include a first estimation method that estimates the state using magnitude of fluctuation in the voltage, a second estimation method that estimates the state using a difference between a mean value of the voltage during charging and a mean value of the voltage during discharging, and a third estimation method that estimates the state using a mean value of fluctuation in the voltage, and
• the one or more processors are configured to:
• select the first estimation method, when the switching ratio is greater than a first threshold,
• select the second estimation method, when the switching ratio is equal to or less than the first threshold, the data number ratio is outside a first specified range, and the mean ratio is outside a second specified range, and
• select the third estimation method, when the switching ratio is equal to or less than the first threshold, and the data number ratio is within the first specified range or the mean ratio is within the second specified range.