A method of evaluating a power storage device comprising at least: preparing a power storage device , the power storage device including at least a housing and an electrode assembly , the electrode assembly being accommodated in the housing , the electrode assembly including a positive electrode and a negative electrode , at least one positive electrode and at least one negative electrode being alternately stacked to form a stack portion in the electrode assembly ; adjusting a charge level of the power storage device to produce a first potential difference (ΔV1) between the positive electrode and the negative electrode ; selecting the positive electrode or the negative electrode as a reference electrode; performing an operation to insert a conductive rod-shaped member into the stack portion along a direction of stack of the positive electrode and the negative electrode while a second potential difference (ΔV2) between the reference electrode and the rod-shaped member is measured after the charge level is adjusted; stopping the rod-shaped member ; and evaluating the power storage device based on a state of the power storage device after the rod-shaped member is stopped, when an electrode with which the rod-shaped member comes in contact first in the stack portion is different from the reference electrode, the operation to insert the rod-shaped member being controlled to stop the rod-shaped member when decrease in absolute value of the second potential difference is detected at least once, and when the electrode with which the rod-shaped member comes in contact first in the stack portion is identical to the reference electrode, the operation to insert the rod-shaped member being controlled to stop the rod-shaped member when increase in the absolute value of the second potential difference is detected at least once. preparing a power storage device , the power storage device including at least a housing and an electrode assembly , the electrode assembly being accommodated in the housing , the electrode assembly including a positive electrode and a negative electrode , at least one positive electrode and at least one negative electrode being alternately stacked to form a stack portion in the electrode assembly ; adjusting a charge level of the power storage device to produce a first potential difference (ΔV1) between the positive electrode and the negative electrode ; selecting the positive electrode or the negative electrode as a reference electrode; performing an operation to insert a conductive rod-shaped member into the stack portion along a direction of stack of the positive electrode and the negative electrode while a second potential difference (ΔV2) between the reference electrode and the rod-shaped member is measured after the charge level is adjusted; stopping the rod-shaped member ; and evaluating the power storage device based on a state of the power storage device after the rod-shaped member is stopped, when an electrode with which the rod-shaped member comes in contact first in the stack portion is different from the reference electrode, the operation to insert the rod-shaped member being controlled to stop the rod-shaped member when decrease in absolute value of the second potential difference is detected at least once, and when the electrode with which the rod-shaped member comes in contact first in the stack portion is identical to the reference electrode, the operation to insert the rod-shaped member being controlled to stop the rod-shaped member when increase in the absolute value of the second potential difference is detected at least once. <EOS>