PURPOSE: To use an empty space between batteries effectively and facilitate the process of movement, transport attain, storage, and installation.

CONSTITUTION: Multiple (two) batteries 1, 2 are covered with outer package tubes 3, 4, and both ends of the batteries 1, 2 are fixed to each other by a conductive terminal 5 and a connection part 6 of the tubes 3, 4. As the batteries 1, 2, any battery can be used under the bare battery condition, to which the outer package is not performed. As the outer package tubes 3, 4, thermal shrinkage film such as polyethylene, polypropylene, and polyester or the like is used.