An electric storage apparatus according to one aspect of an embodiment includes a plurality of storage batteries, a virtual processing unit, and a connection controlling unit. The virtual processing unit virtually and sequentially connects in parallel two or more storage batteries, of the plurality of storage batteries, having a potential difference or potential differences within a predetermined range so as to equalize electric potentials of the two or more storage batteries. The connection controlling unit connects in parallel the two or more storage batteries in a connection order for maximizing the number of the two or more storage batteries to be connected in parallel when the virtual processing unit sequentially connects in parallel the two or more storage batteries in an order from highest electric potential to lowest one and in an order from lowest electric potential to highest one.