CN114649626B

CN114649626B - Electromagnetic wave shielding structure for vehicle

Info

Publication number: CN114649626B
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: 2024-04-05
Anticipated expiration: 2041-12-13
Also published as: JP2022096338A; CN114649626A

Abstract

An electromagnetic wave shielding structure for a vehicle, comprising: a battery pack including a plurality of battery stacks, each of the battery stacks being configured to flow unidirectional current therethrough; and a maintenance plug for cutting off the output of the battery pack by pulling out the battery pack. The maintenance plug is arranged above at least one cell stack in the plurality of cell stacks and is used for allowing current to flow in the direction opposite to the current flowing through the at least one cell stack positioned below.

Description

Electromagnetic wave shielding structure for vehicle

Technical Field

The present invention relates to an electromagnetic wave shielding structure for a vehicle that 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. Japanese patent application laid-open No. 2012-186125 shows that an electromagnetic wave shielding sheet is disposed on a cover of a battery case made of resin. As the electromagnetic wave shielding sheet, an electromagnetic wave shielding sheet provided with conductivity by blending a metal having conductivity into a plastic sheet can be exemplified.

Here, the battery of an electric vehicle or the like has 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 connects and accommodates a plurality of the battery stacks in a case.

In addition, in the case of inspection and repair of a vehicle, it is necessary to disconnect a high-voltage battery output from other components, and a maintenance plug is often mounted on a battery pack. The service 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 provided so as to be safe and easy to handle when needed, for example, to be sometimes arranged protruding from the floor of the vehicle and to be covered with a cover. This is usually protected by a cover, and the cover can be removed and operated as necessary.

Disclosure of Invention

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

An electromagnetic wave shielding structure for a vehicle according to the present invention includes: a battery pack including a plurality of battery stacks, each of the battery stacks being configured to flow unidirectional current therethrough; and a maintenance plug for cutting off an output of the battery pack by pulling out the battery pack, wherein the maintenance plug is disposed above at least one of the plurality of battery stacks to allow a current flowing in a direction opposite to a direction of a current flowing through the at least one battery stack located below.

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

Preferably, the plurality of stacks includes a first stack through which a current in a first direction flows and a second stack through which a current in a second direction flows, and the maintenance plug is disposed above the first stacks to flow a current in a second direction opposite to the first direction.

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

According to the invention, the radiation electromagnetic wave from the maintenance plug connector 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, in which like reference numerals denote like elements, and in which:

fig. 1 is a schematic view showing the internal structure of a battery pack 10.

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.

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

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

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

[ constitution of Battery pack ]

Fig. 1 is a schematic view showing the internal structure of a battery pack 10. In this figure, the cover is removed to show the interior of the battery pack 10. The battery current is a discharge current, and hereinafter, it is simply referred to as a current. In the figure, the direction of the current is indicated by a broken arrow.

The housing 12 has a rectangular parallelepiped shape as a whole, and is tapered on the left side in the drawing. When mounted on a vehicle, for example, the tapered portion is located in front of the vehicle, and the front of the drawing is located above the vehicle. The front side of the case 12 is tapered in the right-left direction, and the bottom surface is also directed forward and obliquely upward, so that the space 12a on the front side of the case 12 is relatively narrow. In the space 12a, a battery control unit 14 as a circuit block for controlling charge and discharge of the battery is disposed. The space 12b on the rear side of the case 12 is rectangular parallelepiped, and is relatively wide to accommodate a plurality of stacks 20 therein. The upper surface of the case 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 section 14. In this example, the plurality of stacks 20 are 4 columns, which are connected in series. In the figure, the current flows from left to right in the first stack 20 from top to bottom, from right to left in the third stack 20, from left to right in the second stack 20, and from right to left in the fourth stack 20. Thus, the left side of the first stack 20 is the negative terminal and the left side of the fourth stack 20 is the positive terminal.

A maintenance plug 40 is disposed in a path of current flowing from the first stack 20 to the third stack 20, and the maintenance plug 40 is located above a space between the first stack 20 and the second stack 20, and current flows from right to left in the drawing.

[ maintenance plug 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 the receptacle 46. That is, by inserting the service plug 40 into the socket 46, the battery pack 10 is brought into the connected state, and by removing the service plug 40 from the socket 46, the battery pack 10 is brought into the disconnected state.

The maintenance plug 40 is composed of a resin base 42 and a U-shaped line 44, and both ends 44a, 44b of the line 44 protrude from the base 42. The receptacle 46 is disposed in the middle of the wiring (connection wiring between 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 ends 44a and 44b of the maintenance plug 40. Then, by inserting the both ends 44a, 44b into the receiving ports 46a, 46b, the battery pack 10 is brought into the connected state by the service plug 40, and by extracting the both ends 44a, 44b from the receiving ports 46a, 46b, the battery pack is brought into the disconnected state by the service plug 40.

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

The direction of the current flow of the U-shaped line 48 of the service plug 40 is the same as the direction of the current flow shown in fig. 1. The maintenance plug 40 is operated by grasping the base 42. The receptacle 46 is secured to the housing 12, etc. by suitable means. Further, for the engagement of the maintenance plug 40 and the receptacle 46, a lock unit or the like is preferably provided.

[ reduction of the radiation magnetic field ]

Fig. 4 is a view showing the direction of current flow through the cell stack 20 and the maintenance plug 40, fig. 4 (a) is a schematic plan view, and fig. 4 (b) is a schematic X-X cross-sectional view of fig. 4 (a). In this way, in the two stacks 20, a current in the same direction flows, and a radiation magnetic field is generated by a high frequency superimposed on the current. The service plug 40 is located above the middle of the two stacks 20, in this case, the current flowing counter to the two stacks 20. Therefore, the high frequency superimposed thereon is also phase-inverted, and therefore the magnetic field radiated from the service-plug 40 is canceled by the magnetic fields radiated from the two stacks 20. In particular, since the service-plug 40 is located above the middle of the two stacks 20, the radiation magnetic field from the two stacks 20 easily passes to the side and above the service-plug 40, and the radiation magnetic field from the service-plug 40 to the side and above can be effectively canceled.

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

[ other configuration example ]

Fig. 5 is a diagram showing another configuration example, fig. 5 (a) is a schematic plan view, and fig. 5 (b) is a schematic Y-Y cross-sectional view of fig. 5 (a). In this example, a service plug 40 is arranged above one cell stack 20 in the opposite direction to the cell stack 20. Thereby, the radiation magnetic field from the service plug 40 can be reduced.

Claims

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

a battery pack including a plurality of battery stacks, each of the battery stacks being configured to flow unidirectional current therethrough; and

a maintenance plug for cutting off the output of the battery pack by pulling out the plug from the battery pack,

the maintenance plug is arranged above at least one cell stack in the plurality of cell stacks and is used for allowing current to flow in the direction opposite to the current flowing through the at least one cell stack below.

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

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

the maintenance plug connector is arranged above the first battery stack and the second battery stack and used for allowing current in a second direction opposite to the first direction to flow.

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

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

the maintenance plug connector is arranged above the first battery stacks and used for allowing current in a second direction opposite to the first direction to flow.

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

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