Abstract: This invention is directed to 2,5-dimercapto-1,3,4-thiadiazole dilithium salt and its dihydrate and methods of their manufacture, and a secondary lithium battery and positive electrode-active material comprising the same.

Abstract: An ignition system of an internal combustion engine including a bypass circuit having a switch capable of being closed to cause a current produced by a counter electromotive force generated by a first generating coil to bypass a thyristor, and a second generating coil located anterior to the first generating coil with respect to the direction of rotation of a rotary member supporting a permanent magnet, to generate an electromotive force under the influences of the permanent magnet to cause the thyristor to turn on.

Abstract: An ignition system for an internal combustion engine is provided with an ignition timing retarding circuit to prevent overrunning of the engine. The ignition timing retarding circuit includes a switching circuit connected to the gate of an ignition control thyristor and a predetermined duration signal generator for generating a signal having a predetermined duration from a predetermined reference time. During the time period in which the predetermined duration signal is applied to the switching circuit, the switching circuit is maintained conductive to thereby bypass an ignition signal generated in synchronism with the crankshaft rotation and applied to the gate of the ignition control thyristor.