Abstract: An electrical device body connectable to a battery pack, includes a drive part, and a terminal part. The terminal part having a positive input terminal electrically connected to the drive part, a negative input terminal electrically connected to the drive part, and a short circuit element having a first terminal part, a second terminal part, and a connection part connecting the first terminal part and the second terminal part, wherein the positive input terminal and the negative input terminal are disposed on an upper side of the terminal part and the short circuit element is disposed on a lower side of the terminal part in an upper-lower direction, the positive input terminal and the negative input terminal being apart from each other in a left-right direction crossing the upper-lower direction.

Abstract: A battery pack houses first and second cell units that are composed of a plurality of cells, and has a positive electrode power source terminal and a negative electrode power source terminal. This battery pack is provided with a series connector capable of connecting, in series, the first and second cell units and a parallel connector capable of connecting, in parallel, the first and second cell units, and is capable of switching between a parallel connection voltage and a series connection voltage. In the case of attachment to the high voltage electrical device body, the series connector becomes conductive and the parallel connector pair is cut off by the action of the series/parallel switching terminal. In the case of attachment to a low voltage electrical device body, the state is returned to an initial state, the series connector is cut off, and the parallel connector pair becomes conductive.

Abstract: In an upper cell unit (2146) and a lower cell unit (2147) comprising five battery cells, positive electrode terminals (2162, 2172) are set apart and aligned vertically, and negative electrode terminals (2167, 2177) are set apart and aligned vertically. When an electrical device body is rated at 36V, device-side terminals are in contact only at the upper terminals (2162, 2167), and short circuiting of the lower terminals (2172, 2177) is effected using a short bar 2059. When the electrical device body is rated at 18V, the upper and lower terminals (2162 and 2172, 2167 and 2177) are simultaneously made to contact the device-side terminals, and the upper cell unit (2146) and the lower cell unit (2147) assume a parallel connected state. Thus, it is possible to automatically switch the output voltage when a battery pack is mounted according to the difference in terminal shape on the electrical device body side.

Abstract: In an upper cell unit (2146) and a lower cell unit (2147) comprising five battery cells, positive electrode terminals (2162, 2172) are set apart and aligned vertically, and negative electrode terminals (2167, 2177) are set apart and aligned vertically. When an electrical device body is rated at 36V, device-side terminals are in contact only at the upper terminals (2162, 2167), and short circuiting of the lower terminals (2172, 2177) is effected using a short bar 2059. When the electrical device body is rated at 18V, the upper and lower terminals (2162 and 2172, 2167 and 2177) are simultaneously made to contact the device-side terminals, and the upper cell unit (2146) and the lower cell unit (2147) assume a parallel connected state. Thus, it is possible to automatically switch the output voltage when a battery pack is mounted according to the difference in terminal shape on the electrical device body side.

Abstract: A battery pack houses first and second cell units that are composed of a plurality of cells, and has a positive electrode power source terminal and a negative electrode power source terminal. This battery pack is provided with a series connector capable of connecting, in series, the first and second cell units and a parallel connector capable of connecting, in parallel, the first and second cell units, and is capable of switching between a parallel connection voltage and a series connection voltage. In the case of attachment to the high voltage electrical device body, the series connector becomes conductive and the parallel connector pair is cut off by the action of the series/parallel switching terminal. In the case of attachment to a low voltage electrical device body, the state is returned to an initial state, the series connector is cut off, and the parallel connector pair becomes conductive.

Abstract: A backpack-type power supply includes: a plurality of cell units (52) each configured of a plurality of secondary battery cell (51); a case (12) configured to accommodate the cell units and having first and second contacts; and a harness (13) attached to the case, characterized by including; first connecting means (581, 571) for electrically connecting the first contact and a positive terminal of each cell unit to form a first electrical path therebetween; and second connecting means (572, 582) for electrically connecting the second contact and a negative terminal of each cell unit to form a second electrical path therebetween, each first electrical path and each second electrical path forming a total electrical path having a total resistance for each cell unit, the total resistance of each total electrical path being adjusted such that heat distribution is substantially uniform over the plurality of cell units in the case.

Abstract: A backpack-type power supply includes: a plurality of cell units (52) each configured of a plurality of secondary battery cell (51); a case (12) configured to accommodate the cell units and having first and second contacts; and a harness (13) attached to the case, characterized by including; first connecting means (581, 571) for electrically connecting the first contact and a positive terminal of each cell unit to form a first electrical path therebetween; and second connecting means (572, 582) for electrically connecting the second contact and a negative terminal of each cell unit to form a second electrical path therebetween, each first electrical path and each second electrical path forming a total electrical path having a total resistance for each cell unit, the total resistance of each total electrical path being adjusted such that heat distribution is substantially uniform over the plurality of cell units in the case.

Abstract: A backpack-type power supply includes a rechargeable battery, a case, and a harness. The case accommodates the rechargeable battery. The case has a surface. By the harness, a user wears the case on a back of the user with the surface facing the back. The surface is formed with a recession and a protrusion.