WO2019151726A1

WO2019151726A1 - Fixing element for vehicular battery pack and vehicular battery pack including same

Info

Publication number: WO2019151726A1
Application number: PCT/KR2019/001138
Authority: WO
Inventors: 마사릭칼-마이클; 퓨셔마티아스
Original assignee: 삼성에스디아이 주식회사
Priority date: 2018-01-31
Filing date: 2019-01-28
Publication date: 2019-08-08

Abstract

A battery pack for a vehicle is provided. The battery pack comprises: at least one battery module including a plurality of secondary battery cells; a metal frame for supporting the at least one battery module, the metal frame including a plurality of slots extending from a bottom side of the battery pack toward a mounting side opposite to the bottom side; and an insert which is made of the same kind of material as the metal frame, includes a through hole for receiving a fixing element, and is fixedly fitted in each slot.

Description

Fixing elements for battery packs of vehicles and vehicle battery packs comprising

The present invention relates to a vehicle battery pack, in particular a fixing element useful for mounting the battery pack to a vehicle carrying structure.

In recent years, transportation of goods and people has been developed using power as a source of driving. Such electric vehicles are vehicles driven by electric motors using energy stored in rechargeable batteries. The electric vehicle may be in the form of a hybrid vehicle driven entirely by a battery or driven, for example, by a gasoline generator. The vehicle may also include a combination of an electric motor and a conventional combustion engine. In general, an electric vehicle battery (EVB) or a traction battery (EVB) is a battery used for the promotion of battery electric vehicles (BEV). Electric vehicle batteries are different from start-up, lighting and ignition batteries because they are designed to last for a long time. Rechargeable or secondary cells differ from primary cells in that charging and discharging can be repeated, the latter only providing irreversible conversion of chemicals into electrical energy. Low capacity rechargeable batteries are used as power sources for small electronic devices such as cellular phones, notebook computers and camcorders, while high capacity rechargeable batteries are used as power sources for hybrid cars and the like.

In general, the secondary battery includes an electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode, a case accommodating the electrode assembly, and an electrode terminal electrically connected to the electrode assembly. The electrolyte solution is injected into the case to enable charge and discharge of the battery through the electrochemical reaction of the positive electrode, the negative electrode and the electrolyte solution. For example, the shape of a cylindrical or rectangular case depends on the use of the battery. Lithium ion (and similar lithium polymer) batteries, widely known for use in laptops and consumer electronics, are most prominent in the latest group of electric vehicles under development.

The secondary battery may be used as a battery module formed of a plurality of unit battery cells connected in series and / or in parallel to provide a high energy density, in particular for driving a motor of a hybrid vehicle. That is, the battery module is formed by connecting the electrode terminals of the plurality of unit battery cells in order to implement a high output secondary battery according to the amount of power required.

A battery pack is a set of several (preferably the same) battery modules. They can be configured in series, in parallel, or a mixture of both to provide the desired voltage, capacity or power density. Components of a battery pack include individual battery modules and interconnects that provide electrical conductivity therebetween. Manage battery packs by protecting the battery from operating outside the safe operating area, monitoring its status, calculating auxiliary data, reporting the data, controlling its environment, authenticating, or balancing A battery management system (BMS) is provided.

In order to provide thermal control of a battery pack, a thermal management system is needed to safely use at least one battery module by efficiently dissipating, dissipating and / or dissipating heat generated from a secondary battery. If the heat dissipation / discharge / dissipation is not sufficiently performed, a temperature deviation occurs between each battery cell, and the at least one battery module cannot generate a desired amount of power. In addition, an increase in the internal temperature causes an abnormal reaction therein to decrease the charge and discharge performance of the secondary battery and shorten the life of the secondary battery. Thus, cell cooling is required to effectively dissipate / discharge / dissipate heat from the cell.

Mechanical integration of such battery packs requires proper mechanical connection between individual components, for example battery modules, and between them and the support structure of the vehicle. This connection must remain functional and last for the average service life of the battery system. In addition, installation space and compatibility requirements must be met, especially in automotive applications.

Mechanical integration of the battery module can be accomplished by providing a carrier framework and placing the battery module thereon. Fixing a battery cell or submodule can be accomplished by a depression provided in the frame or by a mechanical interconnect such as a bolt or screw. Alternatively, the battery module is constrained by securing the side plates to the sides of the carrier frame structure. In addition, the cover plate may be fixed to the top and bottom of the battery module.

The carrier frame of the battery pack is mounted to the transport structure of the vehicle. If the battery pack is to be secured to the floor of the vehicle, a mechanical connection can be established at the bottom by a bolt, for example through a carrier frame of the battery pack. The frame is generally made of aluminum or aluminum alloy to lower the total weight of the structure. However, since a vehicle battery pack may have a weight of 600 kg or more, it needs to be fixed at various positions together with the vehicle's transport structure. Each of these fixtures must ensure the robustness and mechanical stability of the battery pack. In the prior art, the fastening involves the use of specially designed steel bushings that are inserted into the slots of the frame and provide through holes for the screws. These bushings need to be coated with a corrosion protection layer together with the frame to avoid corrosion processes. In addition, a seal needs to be formed on the lower side of the steel bushing as well as on the upper side where the screw is fixed by the nut. Finally, the steel bushing includes an anti-twist element to avoid twisting the steel bushing in the slot of the frame. As a result, the manufacturing process of mounting the battery pack on the vehicle's transport structure is complicated and obstructs the automation of the process.

It is therefore an object of the present invention to provide a battery pack that overcomes or reduces at least some of the disadvantages of the prior art and which can be more easily mounted to the vehicle's transport structure. In particular, it should be possible to automate the manufacturing process.

One or more disadvantages of the prior art can be avoided or at least reduced by the present invention. A vehicle battery pack according to an embodiment of the present invention includes at least one battery module including a plurality of secondary battery cells, and a metal frame for supporting the at least one battery module, wherein the frame is a bottom side of the battery pack. A metal frame, comprising a plurality of slots extending from the mounting side to the opposite mounting side, and a through hole made of a material of the same type as the frame, the through hole being adapted to receive the fastening element. Contains an insert.

In other words, the battery pack of the present invention includes a slot formed in a circumferential frame or cross-member that supports a part of the support frame, that is, the internal space of the frame and supports the battery module assembled therein. do. The slot extends from the bottom side of the battery pack to the mounting side on which the battery pack is fixed to the vehicle's transport structure. Within this slot a particular insert is provided which comprises a fixing element, in particular a center through hole, through which the screw passes when the battery pack is mounted to the vehicle. The main advantage of the insert of the invention is that the insert body is made of a material similar to the frame (especially the same). Because the materials are similar, there is no need for a separate anti-corrosion coating of the insert, for example compared to using steel bushings and aluminum frames in the prior art. In addition, the insert and the frame have the same coefficient of thermal expansion. Preferably, the frame and insert are made of aluminum or aluminum alloy.

The insert can be pressed into the slot of the frame of the battery pack in a quick and simple manner that can be performed automatically. Simple sealing is also possible due to the huge sealing surface. For example, a simple flat gasket can be used on both sides of the insert. In addition, mounting the battery pack containing the insert to the vehicle's transport structure is simplified due to the fact that only the fastening elements have to pass through the insert's through holes and no additional elements such as bushings or counter nuts are needed.

According to another preferred embodiment of the present invention, a hole extends from the side of the frame toward the slot and the insert is secured in the slot by a weld joint located in the hole. That is, the fixing of the insert in the slot of the frame is achieved by welding. In principle, such welding may be performed at the bottom side or the mounting side of the frame, but an uneven surface may be formed, which may worsen the sealing of the battery pack. Thus, welding is performed from the side of the insert to the end of the slot through a hole provided in the side of the frame. Setting welding points between parts of the same material, in particular aluminum or aluminum alloys, is easier compared to welding parts made of other materials. Welding can be performed automatically. Finally, no additional torsional element needs to be installed in the welded insert.

More preferably, the insert has a shape that cannot be rotated when it is tightly fitted in the slot. Such an embodiment may have the advantage that the position of the insert is fixed against rotation during welding. In particular, the insert has an elliptical base, since the manufacturing process is simple, the sealing surface is not disturbed by the edges, and the upper and lower surfaces of the insert can be easily used to carry additional functional elements such as holes. It may be a cylindrical body having (see below). However, other insert shapes that cannot rotate in the slot can be realized.

According to another preferred embodiment of the battery pack, the surface of the top of the insert includes a hole for mounting a plate covering the mounting side, or the surface of the bottom of the insert is mounted a plate covering the bottom side of the battery pack It includes a hole for. That is, the attachment of the top and bottom cell covers can be simplified by, for example, self-tapping screws.

According to another aspect of the present invention, there is provided a vehicle comprising the battery pack described above. The battery pack is mounted (directly or indirectly) to the vehicle's transport structure by means of fastening elements, such as screws, which pass through the insert through holes.

Other aspects of the invention can be seen from the dependent claims or the description below.

Features will be apparent to those skilled in the art by describing the exemplary embodiments in detail with reference to the accompanying drawings:

1 is a schematic diagram of a vehicle including a battery pack.

2 is a schematic cross-sectional view of a battery pack according to a conventional technique including a conventional through hole screw coupling.

3 is an enlarged view of a conventional through hole screw coupling used in the battery pack of FIG.

4 is a partial perspective view of a battery pack including an insert for establishing a fixation on a vehicle component, according to one embodiment of the invention.

FIG. 5 is a view of an insert used in the exemplary embodiment of the invention shown in FIG. 4.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, with reference to the accompanying drawings will be described effects and features, and an implementation method according to an embodiment of the present invention. In the drawings, like reference numerals refer to like elements, and redundant descriptions are omitted. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. In addition, the use of “can” when describing embodiments of the invention means “one or more embodiments of the invention”.

Here, the terms "top" and "bottom" are defined along the z axis. For example, the top cover is located above the z axis and the bottom cover below it. In the drawings, the size of components may be exaggerated for clarity. For example, in the drawings, the size or thickness of each component may be arbitrarily presented for purposes of explanation, and thus embodiments of the present invention should not be construed as limited thereto.

In electric or hybrid vehicles, battery packs generally require a huge space inside the undercarriage, ie the floor. Accordingly, the battery pack must provide various fixing devices for fixing to the vehicle carrying structure. 1 simply shows a vehicle 300 that includes a battery pack 10 mounted to the bottom of a transport structure of the vehicle 300.

FIG. 2 is a schematic cross-sectional view of a battery pack 10 of the prior art, which is mounted to a transport structure of a vehicle, such as schematically shown in FIG. 1, by a conventional fixing device. The battery pack 10 includes a plurality of battery modules 12, each of which includes a plurality of secondary battery cells (not shown in detail here). The battery module 12 is assembled in a metal frame 14 that includes an entire peripheral frame 16 and some cross members 18 interposed between each battery module 12. The metal frame 14 for supporting the battery module 12 includes a plurality of through holes 20 extending from the bottom side of the battery pack 10 to the opposite mounting side. The through hole 20 is adapted to receive a screw 22 as a fixing member. The frame 14 may be made of aluminum or an aluminum alloy.

Here, the BIW ("Body In White") or the fixed point of the vehicle is located behind the battery pack 10, and more specifically, the exemplary battery pack 10 is located below the floor on the vehicle floor according to the embodiment of FIG. 1. It is mounted as an application to install. Therefore, the mounting direction is from the bottom side of the battery pack 10 toward the mounting side. To ensure a secure connection, the screw connection incorporates the entire thickness of the battery pack 10 using the through holes 20. Furthermore, the airtightness of the battery pack 10 should not be affected by these through holes 20 in any way during the life of the battery pack.

A method of forming the through hole screw coupling of the conventional battery pack 10 of FIG. 2 is shown in FIG. 3. Here, the rotated steel or steel bushing 24 is attached to the battery pack 10 by the counter nut 26. The head of the steel bushing 24 includes a torsional protective element 28. Disadvantages of the illustrated solution are as follows: The manufacture of the steel bushing 24 is complex, forming, thread cutting, coating (which is necessary because the materials of the steel bushing and the aluminum frame are different), establishing the torsional protection, and steel Sealing on the lower side of the bushing 24. The assembly of the steel bushing 24 to the battery pack is made by attaching the counter nut 26, which also needs to be sealed accordingly. Thus, to achieve this conventional threaded connection, three parts of the coated steel bushing 24, the counter nut 26 and the screw 22 are required. Therefore, the automation of the process is complicated.

4 shows details of an embodiment according to an exemplary embodiment of the invention. More specifically, the figure shows a perspective view of a portion of a battery pack comprising an insert 200 of the present invention for easier fixing to a vehicle component, in particular its carrying structure. Basically, the battery pack according to the illustrated embodiment may be the same as that shown in FIG. 2 except for the presence of the existing through hole 20 for screw connection. The battery pack may be mounted to the floor of the vehicle as schematically shown in FIG. 1.

The embodiment of FIG. 4 deviates from the exemplary conventional form shown in FIG. 2 in that the slot 102 of the elliptical base is formed by cutting the frame 100 to secure space therein. The slot 102 extends from the bottom side of the battery pack to the mounting side. The frame may be made of aluminum or an alloy thereof. The insert 200 fits tightly in the slot 102. That is, the insert 200 has a cylindrical shape with an elliptical base corresponding to the shape of the slot 102.

The frame 100 further includes a hole 110 at its side that extends into the slot 102, which extends toward the top of the slot 102 perpendicular to the longitudinal direction of the frame. After placing the insert 200 in the slot 102, a weld is performed to establish a weld joint 220 in the hole 110 to engage the frame and the insert 200. An additive material may be established in the weld joint 220.

Insert 200 is shown individually in FIG. 5 and includes a through hole 202 located centrally. The through hole 202 houses the screws 122 (see FIG. 4) needed to attach the battery to the vehicle's transport structure. The insert 200 may be made of the same material as the frame, in particular extruded aluminum.

The upper surface 204 of the insert 200 may be provided with a hole 210 in the mounting side (ie, the side opposite to the vehicle's transport structure), which forms a plate that may cover the mounting side of the insert 200. It is provided for fixing. In addition, a hole for fixing another plate covering the bottom side of the battery pack (not shown) may be further provided on the bottom surface of the insert 200.

Although the embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Of course it belongs.

Claims

At least one battery module including a plurality of secondary battery cells;

A metal frame for supporting the at least one battery module, the frame comprising a plurality of slots extending from a bottom side of the battery pack to an opposite mounting side; And

Inserts made of the same material as the frame and tightly fitted in each slot, including through holes arranged to receive the fastening elements

Vehicle battery pack comprising a.
The battery pack of claim 1, wherein the frame and the insert are made of aluminum or an aluminum alloy.
The battery pack according to claim 1 or 2, wherein a hole extends from the side of the frame toward the slot and the insert is fixed in the slot by a weld joint located in the hole.
The battery pack of claim 1 wherein the insert has a shape that cannot be rotated when tightly fitted in the slot.
The battery pack of claim 4 wherein the insert is a cylindrical body having an elliptical base.
The method of claim 1, wherein the top surface of the insert includes a hole for mounting a plate covering the mounting side, or the surface of the insert bottom includes a hole for mounting a plate covering the bottom side of the battery pack , Battery pack.
In a vehicle comprising a battery pack,

At least one battery module including a plurality of secondary battery cells;

A metal frame for supporting the at least one battery module, the frame including a plurality of slots extending from a bottom side of the battery pack to an opposite mounting side; And

An insert made of the same material as the frame, the insert being tightly fitted in each slot, the through hole being adapted to receive the securing element,

And the battery pack is mounted to the transport structure of the vehicle by a fixing element passing through the through hole of the insert.