A battery-powered portable tool (1) and/or a battery pack (174; 174′) connected thereto contain(s) a high-temperature measurement circuit (61, 62, 64; 64-67), a low-temperature measurement circuit (61, 64; 64-66), and a switching apparatus (63; Q 1, Q 2) for selecting and/or outputting a signal from (i) the low-temperature measurement circuit when an output value of the high-temperature measurement circuit enters an abnormal range or (ii) the high-temperature measurement circuit when an output value of the low-temperature measurement circuit enters an abnormal range, which are powered by at least one all-solid-state battery (12, 14, 16, 18) provided in the battery pack. Such an arrangement makes it possible to efficiently make use of the at least one all-solid-state battery that is usable over a wide temperature range, whereby the battery-powered tool becomes usable over a wider temperature range than known battery-powered tools.