Abstract: A battery electrode material composed of a composite material including fiber agglomerates having micro-pores and an electrode active material included within the micro-pores of the fiber agglomerates. The agglomerates are formed by tangled masses of vapor-grown carbon fibers having fiber contact points. Furthermore, at least a portion of the fiber contact points are chemically bonded fiber contact points. Also disclosed is a secondary battery including electrodes made from the battery electrode material.

Abstract: A carbon fiber material is substantially constituted by fiber agglomerates, having agglomerate sizes in a range of not less than 5 .mu.m and not more than 500 .mu.m, formed by vapor grown carbon fibers having a diameter of not less than 0.05 .mu.m and not more than 5 .mu.m, having a microstructure such that some fiber contact points are bonded together with substances produced by carbonizing carbonaceous matters. This carbon fiber material is used as a filler material to various matrices, and used also as an electrode material for making electrodes in batteries, especially in electric double-layer capacitors, and in secondary batteries, especially those based on lithium or lead.

Abstract: A method of transmitting digital signals which allows transmission of signals at a different transmission speed from that of composite serial digital signals, without any changes in the internal configurations of transmitting systems based on time division multiplexing, and a transmitter and a receiver used therefor. Dummy data is added to component serial digital signals inputted through an input terminal 10, with a decoder 21, a dummy data add circuit 22 and a 35/33 multiply circuit 23, to convert them into redundant component parallel digital signals of a sampling frequency twice the frequency of the composite parallel digital signals. The signals are converted into two series of pseudo composite serial signals with an encoder 24, a ten-fold multiply circuit 25 and a switching circuit 26, and then sent to a time division multiplexer for a plurality of composite serial digital signals.