Estimation method, estimation system, and non-transitory computer-readable recording medium

An estimation system comprising a processor that:

• performs, for each different degradation degree among a plurality of degradation degrees, regression analysis between a first value and a second value, wherein
• the first value is related to one or more reference feature points on a differential curve of a charging-discharging curve indicating a voltage value with respect to integrated current amount of a reference storage battery, and
• the second value is at least one of a capacity value of the reference storage battery and an internal resistance value of the reference storage battery;
• and
• estimates at least one of a capacity value of a target storage battery and an internal resistance value of the target storage battery, based on a result of the regression analysis and a third value related to one or more target feature points on a differential curve of a charging-discharging curve indicating a voltage value with respect to integrated current amount of the target storage battery.

A non-transitory computer-readable recording medium having stored therein estimation instructions that cause a computer to:

• perform, for each different degradation degree among a plurality of degradation degrees, regression analysis between a first value and a second value, wherein
• the first value is related to one or more reference feature points on a differential curve of a charging-discharging curve indicating a voltage value with respect to integrated current amount of a reference storage battery, and
• the second value is at least one of a capacity value of the reference storage battery and an internal resistance value of the reference storage battery;
• and
• estimate at least one of a capacity value of a target storage battery and an internal resistance value of the target storage battery, based on a result of the regression analysis and a third value related to one or more target feature points on a differential curve of a charging-discharging curve indicating a voltage value with respect to integrated current amount of the target storage battery.