Patent ID: 7183014
Filing Date: 2007-02-27
Classification: H01M,H02J,H04M,Y02E

Abstract:
1. A primary battery pack for being used as an alternative power source of a portable cellular phone, said portable telephone comprising: an internal circuit and a battery mounting section for mounting a dedicated secondary battery therein, wherein said dedicated secondary battery is so configured to be charged in a charging mode and to feed power to said internal circuit in an operating mode through a pair of common terminals provided in said battery mounting section, said primary battery pack to be mounted in said battery mounting section in such a manner so as to be spatially replaceable with said dedicated secondary battery, said primary battery pack comprising: a pair of connection terminals to be connected with said pair of said common terminals; a power storing unit and a primary battery which are electrically connected between said pair of said connection terminals in such a manner that said power storing unit and said primary battery are electrically connected with each other in parallel; a package for housing said primary battery and said power storing unit, wherein said power storing unit and said primary battery are so configured to feed power in the operating mode to said internal circuit of the portable cellular phone through said pair of said common terminals; a current limiting circuit to limit and output an electromotive force of said primary battery to a current level being a predetermined value or less; a DC/DC (Direct Current/Direct Current) converter to boost a voltage of the electromotive force of said primary battery fed from said current limiting circuit to a voltage level of said dedicated secondary battery; and a voltage detector to detect a voltage output from said DC/DC converter, to produce a negative feedback signal based on the detection result and to transmit the produced negative feedback signal to said DC/DC converter, the negative feedback signal being used to exert negative-feedback controlling on the voltage output from said DC/DC converter, and the voltage output from said DC/DC converter being fed to said power storing unit.