Fixing element for a battery pack of a vehicle, and battery pack for vehicle including the same

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 framework for supporting the at least one battery module, the framework including a plurality of slots extending from a bottom side to an opposing mounting side of the battery pack, and an insert tightly positioned within each slot, the insert being made of a similar material as the framework and including a through-hole adapted for accommodating a fixation element.

Claims

1. A battery pack for a vehicle, comprising: at least one battery module including a plurality of secondary battery cells; a metal framework for supporting the at least one battery module, the framework including a plurality of slots extending from a bottom side to an opposing mounting side of the battery pack; and an insert tightly positioned within each slot, the insert being made of a similar material as the framework and including a through-hole adapted for accommodating a fixation element.

2. The battery pack of claim 1, wherein the framework and the insert are made of aluminum or an aluminum alloy.

3. The battery pack of claim 1, wherein a hole is extending from a side surface of the framework towards the slot and the insert is fixed within the slot by means of a welded joint placed within the hole.

4. The battery pack of claim 1, wherein the insert has a shape, which cannot be rotated, when tightly positioned within the slot.

5. The battery pack of claim 4, the insert is a cylindrical body having an elliptic base.

6. The battery pack of claim 1, wherein a surface of an upper end of the insert includes holes for mounting a plate covering on the mounting side or a surface of a lower end of the insert includes holes for mounting a plate covering the bottom side of the battery pack.

7. A vehicle including a battery pack comprising: at least one battery module including a plurality of secondary battery cells; a metal framework for supporting the at least one battery module, the framework including a plurality of slots extending form a bottom side to an opposing mounting side of the battery pack; and an insert tightly positioned within each slot, the insert being made of a similar material as the framework and including a through-hole arranged for accommodating a fixation element, wherein the battery pack is mounted to a carrying structure of the vehicle by means of fixation elements passing the through-holes of the inserts.

Description

DESCRIPTION OF THE DRAWINGS

(1) Features will become apparent to those of ordinary skill in the art by describing in detail exemplary embodiments with reference to the attached drawings in which:

(2) FIG. 1 is a schematic view on a vehicle including a battery pack.

(3) FIG. 2 illustrates a schematically sectional view on a battery pack according to the conventional art including a conventional through-hole screwing connection.

(4) FIG. 3 is an enlarged illustration of the conventional through-hole screwing connection used in the battery pack of FIG. 2.

(5) FIG. 4 illustrates a partly perspective view on a battery pack according to one embodiment of the present invention and including an insert for establishing a fixation to a vehicle part.

(6) FIG. 5 is a view on the insert used the exemplary embodiment of the present invention shown in FIG. 4.

MODE FOR INVENTION

(7) Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. Effects and features of the exemplary embodiments, and implementation methods thereof will be described with reference to the accompanying drawings. In the drawings, like reference numerals denote like elements, and redundant descriptions are omitted. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Further, the use of “may” when describing embodiments of the present invention refers to “one or more embodiments of the present invention.”

(8) Herein, the terms “upper” and “lower” are defined according to the z-axis. For example, the upper cover is positioned at the upper part of the z-axis, whereas the lower cover is positioned at the lower part thereof. In the drawings, the sizes of elements may be exaggerated for clarity. For example, in the drawings, the size or thickness of each element may be arbitrarily shown for illustrative purposes, and thus the embodiments of the present invention should not be construed as being limited thereto.

(9) In electric or hybrid vehicles the battery packs usually demand huge spaces inside the lower vehicle body, i.e. floor. Therefore the battery pack has to provide several fixation measures to ensure fixation to the vehicle carrying structure. FIG. 1 illustrates in a simple way a vehicle 300 including a battery pack 10 mounted at the bottom of a carrying structure of the vehicle 300.

(10) FIG. 2 is a schematically sectional view through a battery pack 10 of the state of art being mounted to a carrying structure of a vehicle, like the one illustrated schematically in FIG. 1, by means of a conventional fixation. The battery pack 10 comprises a number of battery modules 12, each including a plurality of secondary battery cells (here not shown in detail). The battery modules 12 are assembled within a metal framework 14, which includes an overall circumferential frame 16 and several cross members 18 interposed between each of the battery modules 12. The metal framework 14 for supporting the battery modules 12 includes a plurality of through-holes 20 extending from a bottom side to an opposing mounting side of the battery pack 10. The through-holes 20 are adapted for accommodating a screw 22 as a fixation member. The framework 14 may be made of aluminum or an aluminum alloy.

(11) Here, the fixation points of the BIW (“Body In White”) or vehicle are located behind the battery pack 10, more specifically, the exemplary battery pack 10 is mounted as an underfloor application to the vehicle floor which complies to the embodiment of FIG. 1. Thus, the mounting direction is from the bottom side towards the mounting side of the battery pack 10. To ensure a rigid connection the screw connections have to incorporate the complete thickness of the battery pack 10 by using the through-holes 20. Furthermore, the tightness of the battery pack 10 shall not be affected by these through-holes 20 in any way over the complete battery service lifetime.

(12) A way to establish a through-hole screwing connection of the conventional battery pack 10 of FIG. 2 is shown in FIG. 3. Here a turned steel part or steel bushing 24 is used which is attached to the battery pack 10 by a counter nut 26. A head of the steel bushing 24 includes twist protection elements 28. The disadvantages of the illustrated solution are as follows: Manufacturing of a steel bushing 24 is complex and consists of the steps of shaping, thread cutting, coating (which is needed due to different materials of the steel bushing and aluminum framework), establishing the twist protection, and establishing sealing on lower side of the steel 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. Hence, for establishing such a conventional screw connection three parts are required, namely a coated steel bushing 24, a counter nut 26 and a screw 22. Accordingly, automatization of the process is complicated.

(13) FIG. 4 shows details of an embodiment according to an exemplary embodiment of the present invention. More specifically, the drawing illustrates a perspective view on a part of a battery pack including an inventive insert 200 for more easily establishing a fixation to a vehicle part, in particular a carrying structure thereof. Basically, the battery pack according to the illustrated embodiment may be the same as shown in FIG. 2 except the presence of conventional through-holes 20 for screw connections. The battery pack may be mounted to the floor of a vehicle as schematically shown in FIG. 1.

(14) The embodiment of FIG. 4 departs form the exemplary conventional shape illustrated in FIG. 2 in that a slot 102 of elliptic base is formed by cutting the framework 100 to secure a space therein. The slot 102 extends from a bottom side of the battery pack to a mounting side of the same. The framework may be made of aluminum or an alloy thereof. Within said slot 102 the insert 200 is tightly fitted, i.e. the insert 200 has a cylindrical shape with an elliptic base which corresponds to the shape of the slot 102.

(15) The framework 100 further includes a hole 110 leading into the slot 102 on its side, and the hole 110 extends perpendicular to a longitudinal direction of the framework upwardly towards the slot 102. After positioning of the insert 200 within the slot 102, welding is performed such that a welding joint 220 is established within the hole 110 so as to establish a jointing between the framework and the insert 200. An additional substance may be established in the welding joint 220.

(16) The insert 200 is illustrated separately in FIG. 5 and includes a centrally located through-hole 202. The through-hole 202 is housing a screw 122 (See FIG. 4) necessary to attach the battery to the carrying structure of the vehicle. The insert 200 may be made of the same material as the framework, in particular extruded aluminum.

(17) On an upper surface 204 of the insert 200 holes 210 may be provided on the mounting side (i.e. the side facing the carrying structure of the vehicle), and they are provided for fixing a plate that can cover the mounting side of the insert 200. Further holes may be also provided on the lower surface of the insert 200 so as to fix another plate covering to the bottom side of the battery pack (not shown).

(18) Although the embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made within the scope of the claims, the description, and the accompanying drawings, which also belong to the scope of the present invention.