| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a secondary battery pack for electric tools, which can display abnormality of a secondary battery by a single secondary battery pack without increasing a size of the secondary battery pack. <P>SOLUTION: The secondary battery pack includes: a display portion including four display elements (LED) for displaying residual capacity and abnormality of a secondary battery; a display switch for inputting a display command; and an MCU (Main Control Unit) controlling the display portion and the like. The MCU displays the residual capacity of the secondary battery by controlling the number of lighted display elements in the four display elements when the display switch is operated (S140 and S150). The MCU further determines the abnormality of the secondary battery (S120) and displays the detected abnormality content prior to displaying the residual capacity, by using the four display elements (S200) when the display switch is operated (YES in S180) or a main switch of an electric tool body is turned on (YES in S190) while the abnormality of the secondary battery is detected (YES in S130). <P>COPYRIGHT: (C)2012,JPO&INPIT |
