Abstract: A secondary battery management device is connected with electronic equipment using a secondary battery as a driving power supply via the Internet. The secondary battery management device acquires performance information of the secondary battery from the electronic equipment, and measures a degradation level of performance of the secondary battery during a predetermined unit period. The secondary battery management device estimates a degrading speed of the secondary battery on the basis of the degradation level. The secondary battery management device may notify a user of the electronic equipment of the replacement timing of the secondary battery, use fees of the secondary battery, and the like.