Washer for an electrical energy store, electrical energy store, arrangement and motor vehicle
A washer to be arranged in a mechanical connection between an energy storage module and a housing of an electrical energy store for a motor vehicle includes an axial hole for receiving a connector and axially opposing bearing surfaces for pressing against metal contact surfaces of the energy storage module and the housing. The washer has a metal bushing for providing a current path between the contact surfaces for potential equalization between the energy storage module and the housing, the axially opposing faces of the bushing forming the bearing surfaces. The bushing has, between the faces, a tapering cross section forming a fuse for interrupting the current path in the event of overcurrent. A thermally insulating material surrounds the metal bushing at least in the region of the tapering cross section and compensates for the tapering cross section in order to provide a substantially constant outer diameter of the washer and to reduce the thermal conductivity of a heat-conducting path formed by the washer between the housing and the energy storage module.
1 . A washer to be arranged in a mechanical connection between an energy storage module and a housing of an electrical energy store for a motor vehicle, the washer comprising:
a metallic bushing for providing a current path between axially opposite abutment surfaces of the metallic bushing for pressing against metallic contact surfaces of the energy storage module and the housing for potential equalization between the energy storage module and the housing, wherein
metallic axially opposite end faces of said metallic bushing form the axially opposite abutment surfaces,
the metallic bushing has, between the axially opposite end faces, a cross-sectional tapering, which tapering forms a fuse for interrupting a current path in an event of an overcurrent, and
the metallic bushing has an axial hole for receiving a connector of the mechanical connection; and
a thermally insulating material surrounding the metallic bushing at least in a region of the cross-sectional tapering, wherein
the thermally insulating material compensates for the cross-sectional tapering to provide a substantially constant outer diameter of the washer and to reduce a thermal conductivity of a heat-conducting path, formed via the washer, between the housing and the energy storage module.
2 . The washer according to claim 1 , wherein the thermally insulating material is a glass-fiber-reinforced thermoset.
3 . The washer according to claim 1 , wherein the washer is of hollow-cylindrical form.
4 . The washer according to claim 1 , wherein
the metallic bushing has two plate-shaped end pieces, surfaces of which form the metallic axially opposite end faces and which are connected by way of the cross-sectional tapering, and
the thermally insulating material is arranged between the two plate-shaped end pieces and surrounds the cross-sectional tapering.
5 . The washer according to claim 1 , wherein
the metallic bushing has a double cone form at least in the region of the cross-sectional tapering.
6 . An electrical energy store for a motor vehicle, comprising:
at least one energy storage module;
a housing for receiving the at least one energy storage module;
at least one connector for providing a mechanical connection between metallic contact surfaces of the at least one energy storage module and of the housing; and
at least one washer arranged between the energy storage module and the housing, the washer comprising:
a metallic bushing for providing a current path between axially opposite abutment surfaces of the metallic bushing for pressing against the metallic contact surfaces of the energy storage module and the housing for potential equalization between the energy storage module and the housing, wherein
metallic axially opposite end faces of said metallic bushing form the axially opposite abutment surfaces,
the metallic bushing has, between the axially opposite end faces, a cross-sectional tapering, which tapering forms a fuse for interrupting a current path in an event of an overcurrent, and
the metallic bushing has an axial hole for receiving the at least one connector of the mechanical connection; and
a thermally insulating material surrounding the metallic bushing at least in a region of the cross-sectional tapering, wherein
the thermally insulating material compensates for the cross-sectional tapering to provide a substantially constant outer diameter of the washer and to reduce a thermal conductivity of a heat-conducting path, formed via the washer, between the housing and the energy storage module.
7 . The electrical energy store according to claim 6 , wherein
the metallic contact surface of the energy storage module is formed on a cell module frame for holding energy storage cells of the energy storage module.
8 . An arrangement for a motor vehicle, comprising:
a heat source of the motor vehicle;
an electrical energy store, the electrical energy store comprising:
at least one energy storage module;
a housing for receiving the at least one energy storage module, wherein the heat source is configured to introduce heat into the housing;
at least one connector for providing a mechanical connection between metallic contact surfaces of the at least one energy storage module and of the housing; and
at least one washer arranged between the energy storage module and the housing, the washer comprising:
a metallic bushing for providing a current path between axially opposite abutment surfaces of the metallic bushing for pressing against the metallic contact surfaces of the energy storage module and the housing for potential equalization between the energy storage module and the housing, wherein
metallic axially opposite end faces of said metallic bushing form the axially opposite abutment surfaces,
the metallic bushing has, between the axially opposite end faces, a cross-sectional tapering, which tapering forms a fuse for interrupting a current path in an event of an overcurrent, and
the metallic bushing has an axial hole for receiving the at least one connector of the mechanical connection; and
a thermally insulating material surrounding the metallic bushing at least in a region of the cross-sectional tapering, wherein
the thermally insulating material compensates for the cross-sectional tapering to provide a substantially constant outer diameter of the washer and to reduce a thermal conductivity of a heat-conducting path, formed via the washer, between the housing and the energy storage module.
9 . The arrangement according to claim 8 , wherein
the heat source is a pipe of an exhaust-gas system of the motor vehicle, and
the housing has at least two adjacent housing regions between which the pipe runs.
10 . A motor vehicle comprising an arrangement according to claim 8 .
11 . The motor vehicle according to claim 10 , wherein the motor vehicle is a hybrid vehicle.
12 . The motor vehicle arrangement according to claim 11 , wherein
the heat source is a pipe of an exhaust-gas system of the motor vehicle, and
the housing has at least two adjacent housing regions between which the pipe runs.