CN114649626A

CN114649626A - Electromagnetic wave shielding structure for vehicle

Info

Publication number: CN114649626A
Application number: CN202111520111.1A
Authority: CN
Inventors: 木下阳介
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2020-12-17
Filing date: 2021-12-13
Publication date: 2022-06-21
Anticipated expiration: 2041-12-13
Also published as: CN114649626B; JP2022096338A

Abstract

An electromagnetic wave shielding structure for a vehicle, comprising: the battery pack comprises a plurality of battery stacks, and each battery stack is used for allowing unidirectional current to flow through; and a maintenance connector which cuts off an output of the battery pack by being pulled out from the battery pack. The maintenance plug is disposed above at least one of the plurality of cell stacks, and allows a current flowing in a direction opposite to a direction of a current flowing through at least one of the cell stacks located below to flow therethrough.

Description

Electromagnetic wave shielding structure for vehicle

Technical Field

The present invention relates to an electromagnetic wave shielding structure for a vehicle, which shields electromagnetic waves radiated from a battery pack mounted on the vehicle.

Background

Conventionally, it is known to add a function of shielding electromagnetic waves to a battery case of an electric vehicle or the like. Jp 2012 a 186125 a shows an electromagnetic wave shielding sheet disposed on a cover of a battery case made of resin. As the electromagnetic wave shielding sheet, there is an electromagnetic wave shielding sheet in which conductivity is imparted by blending a plastic sheet with a conductive metal.

Here, batteries for electric vehicles and the like have large electric power, and many battery cells are required. Therefore, a battery pack is used which is provided with a battery stack composed of a plurality of battery cells and which is connected in plurality and accommodated in a case.

In addition, when the vehicle is inspected and repaired, the high-voltage battery output must be disconnected from other components, and many battery packs are equipped with a maintenance plug. The maintenance plug is a plug that cuts off the output of the battery pack by pulling it out of the battery pack. The service plug needs to be arranged to be safe and easy to handle when needed, for example sometimes arranged protruding from the floor of the vehicle and covered with a cover. This makes it possible to protect the mask with the mask in normal use and to remove the mask when necessary for handling.

Disclosure of Invention

In the maintenance plug as described above, a battery current flows in a normal state. Since a high frequency is superimposed on the battery current, electromagnetic waves are also radiated from the maintenance plug, and this shielding measure is required.

An electromagnetic wave shielding structure for a vehicle according to the present invention includes: the battery pack comprises a plurality of battery stacks, and each battery stack is used for allowing unidirectional current to flow through; and a maintenance connector which cuts off an output of the battery pack by being pulled out from the battery pack, wherein the maintenance connector is disposed above at least one of the plurality of battery stacks, and through which a current in a direction opposite to a direction of a current flowing through the at least one battery stack located below flows.

Preferably, the plurality of cell stacks include a first cell stack and a second cell stack which are adjacent to each other and through which a current flows in a first direction, and the maintenance connector is disposed above and between the first cell stack and the second cell stack and through which a current flows in a second direction opposite to the first direction.

Preferably, the plurality of cell stacks include a first cell stack through which a current flows in a first direction and a second cell stack through which a current flows in a second direction, and the maintenance connector is disposed above and between the first cell stacks and through which a current flows in a second direction opposite to the first direction.

Preferably, the battery pack is disposed outside a vehicle compartment below a floor panel of the vehicle compartment, and the maintenance plug is disposed above the floor panel or disposed in an opening provided in the floor panel.

According to the present invention, the radiated electromagnetic waves from the service plug can be effectively shielded.

Drawings

Features, advantages and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, wherein like reference numerals denote like elements, and wherein:

fig. 1 is a diagram schematically showing the internal configuration of a battery pack 10.

Fig. 2 is a schematic diagram illustrating the maintenance plug 40, in which fig. 2 (a) shows a disconnected state and fig. 2 (b) shows a connected state.

Fig. 3 is a diagram showing a state of arrangement of the maintenance plug.

Fig. 4 is a diagram showing the direction of current flow between the battery stack 20 and the maintenance plug 40, fig. 4 (a) is a schematic top view, and fig. 4 (b) is a schematic X-X cross-sectional view of fig. 4 (a).

Fig. 5 is a view showing another configuration example, fig. 5 (a) is a schematic plan view, and fig. 5 (b) is a schematic Y-Y sectional view of fig. 5 (a).

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described herein.

[ construction of Battery pack ]

Fig. 1 is a diagram schematically showing the internal configuration of a battery pack 10. In this figure, the interior of the battery pack 10 is shown with the cover removed. The battery current is a discharge current and will be referred to as a current only hereinafter. In the figure, the direction of the current is indicated by a dotted arrow.

The casing 12 is a rectangular parallelepiped in shape as a whole, and is tapered on the left side of the figure. When mounted on a vehicle, for example, the tapered portion is located forward, and the front of the drawing is located above the vehicle. The front side of the housing 12 is tapered in the left-right direction, and the bottom surface is also directed forward and obliquely upward, so that the space 12a on the front side of the housing 12 is relatively narrow. In the space 12a, a battery control unit 14 is disposed as a circuit block for controlling charging and discharging of the battery. The space 12b on the rear side of the case 12 is a rectangular parallelepiped shape and is relatively wide, and a plurality of cell stacks 20 are accommodated therein. The upper surface of the housing 12 is a flat surface, and a cover is disposed therein.

The cable 16 for charging and discharging the battery pack 10 is connected to the battery stack 20 via the battery control unit 14. In this example, the plurality of cell stacks 20 are 4 rows, which are connected in series. In the figure, current flows from left to right in the first cell stack 20 from the top, from right to left in the third cell stack 20, from left to right in the second cell stack 20, and from right to left in the fourth cell stack 20. Thus, the left side of the first cell stack 20 is the negative terminal and the left side of the fourth cell stack 20 is the positive terminal.

A maintenance plug 40 is disposed on a path of the current from the first cell stack 20 to the third cell stack 20, and the maintenance plug 40 is positioned above the space between the first cell stack 20 and the second cell stack 20, and the current is supplied from the right side to the left side in the drawing.

[ maintenance plug-in connector ]

Fig. 2 is a schematic diagram illustrating the maintenance plug 40, where fig. 2 (a) shows a disconnected state and fig. 2 (b) shows a connected state. The service plug 40 is used in pairs with a receptacle 46. That is, the battery pack 10 is in the connected state by inserting the maintenance plug 40 into the receptacle 46, and the battery pack 10 is in the disconnected state by pulling out the maintenance plug 40 from the receptacle 46.

The service plug 40 includes a resin base 42 and a U-shaped wire 44, and both

ends

44a and 44b of the wire 44 protrude from the base 42. The receptacle 46 is disposed in the middle of the wiring (the connection wiring of the first cell stack 20 and the third cell stack 20) in the battery pack 10, and has receiving

ports

46a and 46b for receiving the both

ends

44a and 44b of the maintenance plug 40. Then, the both

ends

44a, 44b are inserted into the

receiving ports

46a, 46b, whereby the maintenance connector 40 brings the battery pack 10 into a connected state, and the both

ends

44a, 44b are pulled out from the

receiving ports

46a, 46b, whereby the maintenance connector 40 brings the battery pack into a disconnected state.

Fig. 3 is a diagram showing the arrangement state of the maintenance plug 40. An opening is provided at the cover 18 of the housing 12 at the location of the service plug 40. A floor panel 52 constituting the floor of the vehicle compartment is positioned on the cover 18, an opening is also provided in a position corresponding to the opening of the cover in the floor panel 52, and the two openings are integrated to form the opening 50. The maintenance plug 40 projects from the opening 50 toward the vehicle compartment side. Further, an interior material 56 is configured to cover the upper side of the service plug 40.

The direction of the current flow in the U-shaped line 48 of the service plug 40 is the same direction as the current flow shown in fig. 1. It should be noted that the service plug 40 is operated by gripping the base 42. The socket 46 is fixed to the housing 12 or the like by an appropriate means. Further, it is preferable to provide a locking means for engagement between the maintenance plug 40 and the receptacle 46.

[ reduction of radiation magnetic field ]

Fig. 4 is a diagram showing the direction of current flow between the battery stack 20 and the maintenance plug 40, fig. 4 (a) is a schematic top view, and fig. 4 (b) is a schematic X-X cross-sectional view of fig. 4 (a). In this way, currents in the same direction flow through the two cell stacks 20, and a radiation magnetic field is generated by a high frequency superimposed on the currents. The service plug 40 is located above the middle of the two cell stacks 20, and a current flows in the opposite direction to the two cell stacks 20. Therefore, the high frequency superimposed thereon is also phase-reversed, and thus the magnetic field radiated from the maintenance plug 40 is cancelled by the magnetic fields radiated from the two cell stacks 20. In particular, since the maintenance plug 40 is located above the middle of the two cell stacks 20, the radiation magnetic field from the two cell stacks 20 easily goes around to the side and above the maintenance plug 40, and the radiation magnetic field from the maintenance plug 40 to the side and above can be effectively cancelled.

As described above, according to the present embodiment, the radiation magnetic field from the maintenance plug 40, that is, the radiation electromagnetic wave can be reduced by the radiation magnetic field from the two cell stacks 20.

[ other constitution examples ]

Fig. 5 is a view showing another configuration example, fig. 5 (a) is a schematic plan view, and fig. 5 (b) is a schematic Y-Y sectional view of fig. 5 (a). In this example, a maintenance plug 40 having a current flow direction opposite to that of the cell stack 20 is disposed above one cell stack 20. Thereby, the radiation magnetic field from the maintenance plug 40 can be reduced.

Claims

1. An electromagnetic wave shielding structure for a vehicle, comprising:

the battery pack comprises a plurality of battery stacks, and each battery stack is used for allowing unidirectional current to flow through; and

a maintenance connector that cuts off the output of the battery pack by pulling out the battery pack,

the maintenance plug is disposed above at least one of the plurality of cell stacks, and allows a current flowing in a direction opposite to a direction of a current flowing through the at least one cell stack located below to flow therethrough.

2. The electromagnetic wave shielding structure of a vehicle according to claim 1,

the plurality of cell stacks includes a first cell stack and a second cell stack adjacent to each other and through which a current flows in a first direction,

the maintenance plug is arranged above the space between the first cell stack and the second cell stack, and current in a second direction opposite to the first direction flows through the maintenance plug.

3. The electromagnetic wave shielding structure of a vehicle according to claim 1,

the plurality of cell stacks includes a first cell stack through which current flows in a first direction and a second cell stack through which current flows in a second direction,

the maintenance plug is disposed above the first cell stack, and a current in a second direction opposite to the first direction flows through the maintenance plug.

4. An electromagnetic wave shielding structure of a vehicle according to any one of claims 1 to 3,

the battery pack is disposed outside the vehicle compartment below a floor panel of the vehicle compartment, and the maintenance plug is disposed above the floor panel or in an opening provided in the floor panel.