[001] The present subject matter described herein, relates to a battery pack mounting structure for a vehicle and, in particularly, to a battery pack mounting structure with a ladder frame that is mounted with chassis or longitudinal member of the vehicle.
BACKGROUND AND PRIOR ART:
[002] Vehicles typically include chassis frames designed to support a multitude of vehicle components and contribute toward vehicle stiffness and performance. Examples of frame configurations may include unibody (i.e., semi-monocoque) frames, perimeter frames, and others. Many frames include longitudinal members over which chassis is mounted.
[003] Some vehicles today are driven at least in part by one or more electric motors. These vehicles include one or more battery packs for supplying power to the one or more electric motors. To increase the range of the vehicle, the battery pack can be quite large and quite heavy which negatively impacts the strength of the vehicle. Strength of the floor or chassis is particularly important with such vehicles for them to grow in acceptance in the marketplace.
[004] The electric vehicles must support the weight of the batteries upon the longitudinal member and having sufficient space for accommodating the battery modules. Further, to maintain desired road clearances, the battery modules are typically located above the chassis frame.
[005] Accordingly, a battery pack mounting structure is desirable which can support battery weight while maintaining and/or meeting other, more traditional structural requirements while reducing system costs, simplifying complexity of design and maintenance processes, and improving robustness.
OBJECTS OF THE INVENTION:
[006] The principal object of the present invention is to provide a battery pack mounting structure for electric vehicle.

[007] Another object of the present subject matter is to provide a battery pack mounting structure with ladder frame structure.
[008] Another object of the present subject matter is to provide a battery pack mounting structure with mounting brackets at lateral ends to mount the battery pack mounting structure with longitudinal members of the vehicle.
[009] Another object of the present subject matter is to provide a battery pack mounting structure with tubular cross members.
[0010] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION:
[0011] One or more drawbacks of conventional battery pack mounting structure are overcome, and additional advantages are provided through the present battery pack mounting structure as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
[0012] The present subject matter relates to a battery pack mounting structure for electric vehicle. The battery pack mounting structure includes a base plate and a ladder frame structure. The ladder frame structure comprises a plurality of cross members longitudinally spaced apart from one-another. Each cross member from the plurality of cross members has a mounting bracket at lateral ends to mount the battery pack mounting structure with the longitudinal members of vehicle. Further, the ladder frame structure includes a plurality of longitudinal support members that is provided in between the plurality of cross members and is engaged with the plurality of cross members at both ends longitudinally. At least two longitudinal support members are provided in between at least two cross members.

[0013] It is preferable that each of the plurality of cross members is tubular structure formed by joining two hat shaped U channels along the extended flanges upto lateral ends of the base plate.
[0014] It is preferable that the base plate is sandwiched between the two hat shaped U channels of the plurality of cross members.
[0015] To further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit scope of the present subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0017] Fig. 1 illustrates bottom perspective view of battery pack mounting structure, in accordance with an embodiment of the present subject matter;
[0018] Fig. 2a illustrates another view of the battery pack mounting structure, in accordance with an embodiment of the present subject matter; and
[0019] Fig. 2b illustrates side view of lateral ends of the cross members, in accordance with embodiment of the present subject;
[0020] Fig. 2c illustrates cross section AA of the lateral ends of the cross members, in accordance with embodiment of the present subject;

[0021] Fig. 3a illustrates perspective view of the battery pack mounting structure, in accordance with embodiment of the present subject;
[0022] Fig. 3b illustrates cross section view BB of figure 3a, in accordance with embodiment of the present subject matter;
[0023] Fig. 4 illustrates ladder frame structure of the battery pack mounting structure, in accordance with embodiment of the present subject;
[0024] Fig. 5 illustrates bottom view of the battery pack mounting structure, in accordance with embodiment of the present subject;
[0025] Fig. 6 illustrates top view of the battery pack mounting structure, in accordance with embodiment of the present subject;
[0026] Fig. 7 illustrates assembly of the battery pack mounting structure with the longitudinal members of the vehicle, in accordance with embodiment of the present subject; and
[0027] Fig. 8 illustrates side view of assembly of the longitudinal member and battery pack mounting structure, in accordance with embodiment of the present subject.
[0028] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0029] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various arrangements that, although not

explicitly described or shown herein, embody the principles of the present subject matter and are included within its scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts
5 contributed by the inventor(s) to furthering the art and are to be construed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when
10 considered in connection with the accompanying figures.
[0030] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise 15 various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0031] As shown in the figures, the vehicle length direction is referred as longitudinal direction and the vehicle width direction is referred as lateral direction.
[0032] FIG. 1 illustrates bottom perspective view of battery pack mounting structure 20 for electric vehicle, in accordance with an embodiment of the present subject matter. The battery pack mounting structure 100 includes a base plate 101, a ladder frame structure 102, and a battery cover 103. The ladder frame structure 102 extends longitudinally along vehicle length. The ladder frame structure 102 is mounted with longitudinal members of the vehicle at lateral ends. Further mounting of the ladder 25 frame structure 102 with the longitudinal member is explained in subsequent figures. Figure 1 shows bottom perspective view of the battery pack mounting structure 100 with bottom surface 101b of the base plate 101 and figure 3a shows top surface 101a of the base plate 101 when the battery pack mounting structure 100 is referred from top of the vehicle.
6

[0033] Fig. 2a illustrates top view of the battery pack mounting structure as shown in the figure 1. The battery pack mounting structure 100 has a cylindrical rod 105 provided laterally at rear end 100b of the ladder frame structure 400 (as explained in figure 4). The cylindrical rod 105 has a mounting bracket 104 at lateral ends to mount 5 the battery pack mounting structure 100 with the longitudinal members of the vehicle. The cylindrical rod 105 is supported by two L shaped bent pipes 107 on rear side cross member at lateral ends. As shown in the figure 2a, the battery cover 103 is mounted on the top of the base plate 101.
[0034] Figures 2b and 2c illustrate tubular structure at lateral ends of the cross
10 members, in accordance with an embodiment of the present subject matter. As shown in the figures, lateral end portions of the cross members are formed by joining two hat shaped U channels. The tubular structure 200 of the lateral end of the cross member 106 includes upper hat shaped U channel 201 having side flanges 201a, 201b and lower hat shaped U channel 202 having side flanges 202a, 202b. The side flanges
15 201a is joined with the side flange 202a of the lower hat shaped U channel. Similarly, the side flange 201b of the upper hat shaped U channel 201 is joined with the side flange 202b of the lower hat shaped U channel 202. The side flanges of the hat shaped U channels are joined by spot welding. Further, joining of the side flanges forms a tubular structure that provides strength to the battery pack mounting structure
20 for catering torsional loads and distributing weight loads of the battery modules mounted over the battery pack mounting structure to longitudinal members of the vehicle. Similarly, lateral ends of all cross members of the ladder frame are formed with tubular box shaped structure by joining side flanges. On the lateral ends of the cross members, mounting brackets are provided for mounting the battery pack
25 mounting structure to longitudinal members of the vehicle. The tubular box shaped structure has capability to cater loads in vertical direction.
[0035] Figure 4 illustrates structure of the ladder frame as shown in figure 1, in accordance with an embodiment of the present subject matter. The ladder frame structure 400 (same as 102 of figure 1) includes a plurality of cross members 30 401a, 401b, 401c, 401d, 401e that are longitudinally spaced apart from one-another. As shown, the cross member 401e is provided towards front end of the
7

vehicle and the cross member 401a is towards rear end of the vehicle. Each cross member from the plurality of cross members 401a…401e has a mounting bracket 406, 104 at lateral ends. The mounting brackets 406, 104 are provided at both lateral ends of each of the cross members. The mounting brackets 406, 104mount 5 the ladder frame with the longitudinal member of the vehicle.
[0036] In an embodiment, the two cross members 401b, 401c may be provided adjacent to each other to provide strength to the structure and to cater loads in lateral direction.
[0037] Further, the ladder frame structure 400 has a plurality of longitudinal 10 support members 402a, 402b, 403a, 403b, 404a, 404b provided in between the plurality of cross members 401a-401e and engaged with the plurality of cross members 401a-401e at both ends longitudinally. At least two longitudinal support members 402a, 402b are provided in between at least two cross members 401a, 401b to provide torsional stiffness and to support the ladder frame in longitudinal 15 direction. The plurality of longitudinal support members 402a, 402b, 403a, 403b, 404a, 404b is joined with the plurality of cross members 401a-401e via spot welding. Further, the plurality of longitudinal support members 402a, 402b, 403a, 403b, 404a, 404b distributes the weight load of battery modules in longitudinal direction along the ladder frame structure 400.
20 [0038] As shown in the figure 1, 2, 4, and 7, each of the plurality of cross members 401a…401e is tubular structure formed by joining two hat shaped U channels along the extended flanges. Referring to figure 4, at the lateral ends of each cross member, a mounting bracket 406, 104 is provided. Each mounting bracket 406, 104 is one face open box shaped bracket that is joined with the cross
25 members via spot welding or by screw bolt mechanism or by any other known means for joining. The mounting brackets 406, 104 are provided to join the battery pack mounting structure 100 with the longitudinal members (as explained in figure 7 and 8) of the vehicle.
[0039] At the rear side of the ladder frame structure 400, a cylindrical rod 105 (as 30 shown in figure 3a) is provided laterally. The cylindrical rod has a mounting bracket
8

at lateral ends to mount the ladder frame structure 400 with the longitudinal members of the vehicle at rear end. The cylindrical rod is supported by two L shaped bent pipes on rear side cross member at lateral ends of the vehicle.
[0040] Referring to figure 5 and 6 that illustrate bottom and top view of the 5 battery pack mounting structure 100. Upon seeing both the figures together, the base plate 101 is sandwiched between the hat shaped U channels of the plurality of cross members 401a…401e. Further, the plurality of longitudinal members 402a…404a and 402b…404b (as shown in figure 4) is spot welded on the base plate 101 at bottom surface 101b that is opposite to the side where battery 10 modules are mounted. Each of the plurality of longitudinal members 402a…404a and 402b…404b is hat shaped U channels that are spot welded on the bottom surface 101b of the base plate 101 and the cross members 401a...401e in longitudinal direction. In other words, the base plate 101, the plurality of cross members 401a…401e and the plurality of longitudinal support members 402a-15 404a and 402b-404b are joined with each other by spot welding.
[0041] Referring to figure 3a that illustrates top view of the battery pack mounting structure 100. Figure 3a also shows top surface 101a of the base plate 101 over which a plurality of battery modules can be mounted. As shown in the figure 3a, the plurality of cross members 401a…401e (as explained in figure 4) provided on top
20 surface 101a of the base plate 101 extend upto lateral ends of the base plate 101 to accommodate a battery cover 103 from top side. Particularly, the hat shaped U channels of the plurality of cross members 401a…401e that are provided on the top surface 101a of the base plate 101 extend upto the lateral ends of the base plate 101 so that the hat shaped structure do not create any hinderance for the
25 battery cover 103 to completely cover and seal the base plate 101 from top side of the base plate 101. Accordingly, the hat shaped U channels of the plurality of cross members 401a…401e are provided only upto the lateral end of the base plate 101. Referring to figure 3a and 5, the hat shaped U channels provided on bottom surface 101b of the base plate 101 are longer than the hat shaped U
30 channels provided on top surface 101a of the base plate 101. Both the hat shaped
9

U channels form the tubular structure having the base plate 101 in between along vehicle lateral or width direction (as explained above). Further, at the lateral ends 106 as shown in figure 2a, a hat shaped U channel piece is provided on the extending lower hat shaped U channel to form the tubular box structure to receive 5 the mounting bracket 406, 104.
[0042] Referring to figure 3b illustrating cross section view along line BB of figure 3a. The cross member 300 forms a tubular structure having the base plate 301 in between upper hat shaped U channel 302 having side flanges 302a, 302b and lower hat shaped U channel 303 having side flanges 303a, 303b. The side flanges
10 302a, 302b are joined with the side flanges 303a, 30b of the lower hat shaped U channel having the base plate 301 in between. The side flanges of the hat shaped U channels and base plate 301 are joined to each other by spot welding. Further, joining of the side flanges forms a tubular structure having the base plate in between them provides strength to the battery pack mounting structure for catering torsional loads
15 and distributing weight loads of the battery modules mounted over the battery pack mounting structure to longitudinal members of the vehicle.
[0043] In an embodiment, the upper hat shaped U channels of the plurality of cross members may have variable length in lateral direction.
[0044] Referring to figures 7 and 8, the battery pack mounting structure 100 is 20 assembled with the longitudinal members 601 of the vehicle. As explained in figure 1, 2, and 4, each cross member has a mounting bracket 406, 104. Further, each mounting bracket is aligned and placed vertically over the cross member without any offset to directly transfer the battery loads to the battery cross members. As shown in figures 7 and 8, the mounting brackets 606a, 607a, 608a, 25 606b, 607b, 608b are open box mounting brackets where base is connected with the cross member and opposite face is open to receive the longitudinal member 601 of the vehicle. The mounting brackets of the battery pack mounting structure 100 are mounted with the longitudinal member 601 by spot welding or by screw bolt mechanism. Similarly, the cylindrical rod 105 has U shaped brackets that
10

engage with the longitudinal member 601 to support the battery mounting structure 100 at rear side.
[0045] Referring to figure 3a that illustrates top view of the battery pack mounting structure 100. A plurality of battery modules is provided on top of the base plate 101.
5 Each battery module is provided in between the plurality of cross members in longitudinal direction. The battery modules directly mounted on the cross member via screws or bolts. Accordingly, weight of the battery modules is transferred to cross members that are connected to the longitudinal members of the vehicle. Finally, weight of the battery modules is transferred to the vehicle chassis, specifically to
10 longitudinal member which distributes the load along the vehicle length. The present battery pack mounting structure can be extended further by addition of cross members and longitudinal members.
[0046] In another embodiment, the base plate 101 may be corrugated plate to 15 optimized weight.
[0047] The term “vehicle” as used throughout this detailed description and in the claims refers to any moving vehicle that is capable of carrying one or more human occupants or goods and is powered by any form of energy. The term “vehicle” is a motor vehicle which includes, but is not limited to: cars, trucks, vans, minivans, 20 hatchback, sedan, MUVs, and SUVs.
[0048] The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, system, assembly that comprises a list of components does not include only those components but may include other components not expressly listed or 25 inherent to such system, or assembly, or device. In other words, one or more elements in a system or device proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.
[0049] It will be understood by those within the art that, in general, terms used 30 herein, and especially in the appended claims (e.g., bodies of the appended
11

claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within
5 the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such
10 phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should
15 typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two
20 recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include
25 but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least
30 one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A,
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B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."
[0050] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of "comprising" or "including" also contemplates embodiments that "consist essentially of or "consist of the recited feature.
[0051] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.

We claim:

A battery pack mounting structure (100) for electric vehicle, the battery
pack mounting structure (100) comprising:
abase plate (101);
a ladder frame structure (102, 400), the ladder frame structure (102, 400) comprising:
characterized in that
a plurality of cross members (401a-401e) longitudinally spaced apart from one-another, wherein each cross member from the plurality of cross members (401a-401e) having a mounting bracket (406, 104, 606a-608a, 606b-608b) at lateral ends; and
a plurality of longitudinal support members (402a-404a, 402b-404b) provided in between the plurality of cross members (401a-401e) and engaged with the plurality of cross members (401a-401e) at both ends longitudinally, wherein at least two longitudinal support members (402a, 402b) are provided in between at least two cross members (401a, 401b),
wherein each of the plurality of cross members (401a-401e) is tubular structure formed by joining two hat shaped U channels along the extended flanges, and
wherein the base plate (101) is sandwiched between the hat shaped U channels of the plurality of cross members (401a-401e).
2. The battery pack mounting structure (100) as claimed in claim 1, wherein each of the plurality of longitudinal support members (402a-404a, 402b-404b) is hat shaped U channel.
3. The battery pack mounting structure (100) as claimed in claim 1, wherein the hat shaped U channels of the plurality of cross members (401a—401e) provided on top surface (101a) of the base plate (101) extend upto lateral ends of the base plate (101) to accommodate a battery cover (103) from top side.

4. The battery pack mounting structure (100) as claimed in claim 1, wherein the hat shaped U channels provided on bottom surface (101b) of the base plate (101) are longer than the hat shaped U channels provided on top surface (101a) of the baseplate (101).
5. The battery pack mounting structure (100) as claimed in claim 1, wherein the base plate (101), the plurality of cross members (401a-401e) and the plurality of longitudinal support members (402a-404a, 402b-404b) are joined by spot welding.
6. The battery pack mounting structure (100) as claimed in claim 1, wherein the mounting brackets (406, 104, 606a-608a, 606b-608b) are one face open box shaped brackets to receive longitudinal members (601, 602) of the electric vehicle.
7. The battery pack mounting structure (100) as claimed in claim 1, wherein a cylindrical rod (105) is provided laterally at rear end (100b) to mount the battery pack mounting structure (100) with longitudinal members (601, 602) of the electric vehicle.
8. The battery pack mounting structure (100) as claimed in claim 7, wherein the cylindrical rod (105) is supported by two L shaped bent pipes (107) that connect the cylindrical rod (105) with the battery pack mounting structure (100).
9. The battery pack mounting structure (100) as claimed in claim 1, wherein the base plate (101) is joined with the ladder frame structure (102, 400) by spot welding.
10. The battery pack mounting structure (100) as claimed in claim 1, wherein a plurality of battery modules is provided in between the plurality of cross members (401a—401e) longitudinally.

11. The battery pack mounting structure (100) as claimed in claim 1, wherein the base plate (101) is corrugated plate.