Abstract: A cell voltage balancer for balancing the voltage of the first cell and the voltage of the second cell. The cell voltage balancer includes the first input terminal, the second input terminal and the third input terminal. The cell voltage balancer includes a transformer, the first switch and the second switch. The transformer includes a primary winding and a secondary winding. The first switch and the primary winding are serially connected between the first input terminal and the second input terminal. The second switch and the secondary winding are serially connected between the second input terminal and the third input terminal. The first switch and the second switch are switched on and off alternatively. While the first switch is on and the second switch is off, the primary winding stores energy of the first cell in the transformer. On the contrary, the secondary winding recovers energy stored in the transformer into the second cell.

Abstract: An immunity testing device formed of a thin sheet of material folded to three portions, and the two end portions; named “front cover”0 and “back cover”; fold back to different sides of the center part; named base seat; to provide protection on both sides of the base seat. Two absorbent sheets bridged with a test paper are fixed on the side of base seat that's facing the front cover. A hole is present at the position of the first absorbent sheet on base seat for specimen application. The front cover is disposed with observation cover plates at the position corresponding to the test paper and/or water-absorbing sheets for observation of test result as well as for preventing pollution before, and after use. The test paper is pre-embedded with antibodies/antigens to capture the corresponding antigens/antibodies in the test specimen as in Immunity method. The used testing device can be burned down to ensure environmental protection.