An apparatus for detecting battery state may comprise a first fuse connected to a positive terminal of a battery; a second fuse connected to a negative terminal of the battery; a high resistance resistor connected to the first fuse and the second fuse and disposed in parallel with the battery; a sensor for measuring a current flowing through the high-resistance resistor or a voltage applied to the high-resistance resistor; and a controller for determining a system voltage and determine whether any of the fuses is blown based on the current measured or the voltage measured.

A battery monitoring apparatus is used in a battery assembly equipped with a plurality of batteries connected in series with each other. A plurality of measuring lines are mounted on a given layer of a multi-layer substrate and work to measure electrical potentials developed at terminals of the batteries, respectively. The measuring lines are classified into measuring line groups in order of electrical potential from lowest to highest. A plurality of solid patterns are arranged on one of layers of the multi-layer substrate other than the given layer and provided one for each of the measuring line groups. The solid patterns overlap the measuring line groups in planar view in a stacking direction of the multi-layer substrate. The solid patterns are arranged away from each other. The higher electrical potentials of the measuring line groups are, the higher electrical potentials of the corresponding solid patterns are.

A battery monitoring apparatus is used in a battery assembly equipped with a plurality of batteries connected in series with each other. A plurality of measuring lines are mounted on a given layer of a multi-layer substrate and work to measure electrical potentials developed at terminals of the batteries, respectively. The measuring lines are classified into measuring line groups in order of electrical potential from lowest to highest. A plurality of solid patterns are arranged on one of layers of the multi-layer substrate other than the given layer and provided one for each of the measuring line groups. The solid patterns overlap the measuring line groups in planar view in a stacking direction of the multi-layer substrate. The solid patterns are arranged away from each other. The higher electrical potentials of the measuring line groups are, the higher electrical potentials of the corresponding solid patterns are.

A protective device for switching off a battery cell of a motor vehicle battery in the event of an electrical short-circuit. The battery cell has two cell terminals and an energy storage unit for storing energy. The energy storage unit is connected to the cell terminals in an electrically conductive manner in order to provide cell voltage to the cell terminals. The protective device detects the short-circuit as a function of at least the cell voltage affecting the battery cell. In this case, the battery cell has the protective device and at least one switching device, which is arranged between the energy storage unit and at least one of the cell terminals. The protective device isolates the energy storage unit from the at least one of the cell terminals in order to switch off the battery cell by the switching device.

A battery module includes: a cell laminated body; a first and a second end plates which are provided at both end portions of the cell laminated body; and a sensor device which is mounted on a mounting surface and detects the voltage of each cell in the cell laminated body. The sensor device includes: a sensor device body; and a sensor fixing portion which is fixed to the first end plate by a fastening member. In the perpendicular direction, an end surface of the fastening member is located to be lower than or equal to an end surface of the sensor device body, the mounting surface of the cell laminated body is located to be lower than a bottom surface of the sensor fixing portion, and an end surface of the first end plate is located to be lower than the mounting surface of the cell laminated body.

A shunt-resistance type current detector includes a flat-plate shaped shunt resistor joined between a flat-plate shaped first bus bar and a flat-plate shaped second bus bar. Each of the bus bars includes respective detection conductors connected to a current detector. The shunt resistor and each of the bus bars are joined via weld parts. A gap for mounting the shunt resistor is formed between the first bus bar and the second bus bar, and projected parts are formed each being projected toward the gap from opposing faces opposing to each other in the gap. The shunt resistor comes an contact with each of the projected parts in a top-and-bottom direction.

A configuration is adopted in which a terminal module includes a voltage detection terminal having a terminal connection part connected to an electrode terminal and a wire connection part connected to a wire, and a protector housing at least part of the voltage detection terminal, with two liquid draining parts each including a first extension part extending downward in the direction of gravity being provided between the terminal connection part and the wire connection part in the voltage detection terminal, and the protector having a housing part housing the liquid draining parts and accumulating liquid that travels along the first extension part.

A configuration is adopted in which a terminal module includes a voltage detection terminal having a terminal connection part connected to an electrode terminal and a wire connection part connected to a wire, and a protector housing at least part of the voltage detection terminal, with two liquid draining parts each including a first extension part extending downward in the direction of gravity being provided between the terminal connection part and the wire connection part in the voltage detection terminal, and the protector having a housing part housing the liquid draining parts and accumulating liquid that travels along the first extension part.

A battery state detection device including a battery post terminal, a case accommodating a circuit board including a current sensing circuit that senses a current by being electrically connected to the battery post terminal, and a harness connection part provided on the case, the harness connection part being capable of having a harness connected thereto, in which the battery post terminal includes a holding part held on one of faces of the case, and an insert part provided in a region from the holding part along a face adjacent to the one of the faces of the case, the battery post terminal contacts the case via at least two faces, the two faces including the one of the faces and the face adjacent to the one of the faces, and the case includes a fitting part, the fitting part being adapted to fit around the insert part by accommodating the insert part.

A battery state detection device including a battery post terminal, a case accommodating a circuit board including a current sensing circuit that senses a current by being electrically connected to the battery post terminal, and a harness connection part provided on the case, the harness connection part being capable of having a harness connected thereto, in which the battery post terminal includes a holding part held on one of faces of the case, and an insert part provided in a region from the holding part along a face adjacent to the one of the faces of the case, the battery post terminal contacts the case via at least two faces, the two faces including the one of the faces and the face adjacent to the one of the faces, and the case includes a fitting part, the fitting part being adapted to fit around the insert part by accommodating the insert part.