The invention is an apparatus for sterilizing surgical batteries. In a closed valve state of the valve element, the rotating shaft seal moves radially due to a pressure difference between a high fluid pressure acting on one side of the valve element and a low fluid pressure acting on the other side and contacts both the valve element and the rotation supporting portion on the high fluid pressure side. The block copolymer has an average styrene content of from about 15% to about 35%, an average diblock content of no less than about 20%, and an average solution viscosity of less than about 1,000 cps. A weight engagement member is rotatably connected to the bracket.