Battery module and method of assembling battery module

Abstract

The invention relates to a battery module, in particular to a battery module comprising at least two galvanic piles. A method of manufacturing the battery module is also disclosed. The battery module includes: a pair of opposing module end plates spaced apart from each other along a longitudinal axis; a first stack; and a second stack. Each of the first and second stacks includes: a series of cells stacked along a longitudinal axis; and a pair of stack end plates disposed at opposite ends of the series of cells and configured to be fixed to each other in an assembly position. In the assembly position, the pair of stack end plates exerts a compressive force on the series of cells along the longitudinal axis and defines the stack length of the respective stack. The compressive force applied to the first stack and the compressive force applied to the second stack are each within a predetermined operable range. The battery module unit is configured such that each of a pair of opposing module end plates is fixedly coupled with a corresponding stack end plate of each of the first and second stacks in a use position. In the use position, the module end plates are spaced apart from each other by a predetermined distance along the longitudinal axis, and the first stack length is different than the second stack length.

Description

TECHNICAL FIELD

[0002] The present invention relates to an electrical cell module, in particular to an electrical cell module comprising at least two cell stacks. A method of manufacturing an electrical cell module is also disclosed. BACKGROUND

[0004] Energy storage systems, including battery modules comprising a plurality of individual cells, are used in a variety of applications including electric vehicles. The basic unit of a power storage system is a cell, also known as a battery or battery cell. Cells typically come in three common forms: pouch, prismatic or cylindrical, depending on the shape and characteristics of the cell body. The cell body houses an electrochemical system for storing energy. As used herein, prismatic cells can also include pouch cells mounted within the cell body, for example a frame or housing, to impart a predetermined shape to the pouch cell. In this way, prismatic cells can include cells having a rigid cell body, as well as cell terminals for extracting electrical charge from the cell.

[0005] It is known that a series of cells are commonly mounted within a frame to provide a cell stack. The cell stack has a stack length which includes the sum of the thicknesses of all the cells within the cell stack.

[0006] Known battery modules can be indirectly mounted to a vehicle chassis within a housing unit to enclose the battery module and provide protection. In some examples, the housing unit also provides space to enclose other electrical systems, for example a power inverter, fuses and safety components, a power distributor or systems for monitoring the performance of the battery module. Therefore, any variation in the increase of the stack length results in a poor fit of the cell stack within the space allocated within the battery module or the vehicle chassis.

[0007] Known methods for manufacturing cells result in a range tolerance in the size of the cell body. Typically, each cell has a tolerance of about + / - 0.3 mm in its thickness, for example, a cell stack formed from 12 cells together would have a cumulative tolerance of about + / - 3.6 mm (i.e. the amount of variation in the stack length). The cumulative tolerance means that there is an inherent risk that a cell stack of a large number of cells, for example 10 or more, will not fit well within the vehicle chassis or housing unit. Cell stacks that do not fit reliably onto the vehicle chassis or housing unit need to be adjusted, increasing manufacturing costs.

[0008] In some known examples, battery module designs are typically small with short stacks containing fewer cells (e.g., fewer than 10) to minimize the cumulative tolerance effects. In some known examples, the stacks are compressed to a fixed stack length to ensure accurate fit within the battery module. However, the potential variability in cell thickness can cause variations in compression on the cells between stacks. Other known stacks employ compressible spacers between cells scattered throughout the stack. Each spacer is compressed to a different degree to accommodate cell thickness tolerances. However, the variable compression applied to each spacer inevitably results in different compressive forces on each cell. Over-compression of the cell risks damaging the cell itself, leading to leakage. Under-compression of the cell means the cell will not operate at optimal efficiency. Furthermore, cells may expand after repeated use, meaning any variations in compression will be exacerbated with stack use, increasing the risk of over-compression and cell damage.

[0009] Some manufacturers grade the cells to measure them before assembly and pair the thinnest cells with the thickest to ensure more consistent stack lengths. The additional time involved in grading increases manufacturing costs and inevitably leads to waste of cells that cannot be supplied with the appropriate cell thickness combinations.

[0010] The purpose of certain examples or embodiments of the present invention is to at least partially solve, mitigate or eliminate at least one problem and / or disadvantage associated with the prior art.

[0011] For example, it would be useful to provide a battery module with multiple stacks, each with a different length. That is, it would be useful for a battery module to accommodate multiple stacks, each with a different stacking length.

[0012] For example, it is also useful to ensure that the battery modules are always accurately and consistently positioned at the mounting points used for installation into the vehicle chassis or housing unit. The mounting points of the battery modules should be independent of the stack length of their battery packs.

[0013] For example, it would be useful to create a fuel cell stack that applies a consistent, repeatable compressive force to the cells in the stack. Summary of the Invention

[0015] The present invention is set forth in the appended claims.

[0016] According to one aspect of the present invention, a battery module is provided, comprising: A pair of opposing module end plates spaced apart from each other along the longitudinal axis; The first fuel cell stack; and Second fuel cell stack; Each of the first and second electric stacks includes: A series of battery cells stacked along the longitudinal axis, and A pair of stack end plates are arranged at opposite ends of a series of cells and configured to be fixed to each other in an assembly position, wherein, in the assembly position, the pair of stack end plates apply compressive force to the series of cells along the longitudinal axis and define the stack length of the respective stack. The compressive forces applied to the first fuel cell stack and the second fuel cell stack are both within a predetermined operable range; and The battery module is configured such that each of a pair of opposing module end plates is fixedly engaged at a usage position with a corresponding stack end plate of each of the first and second battery stacks, such that: The module end plates are spaced apart from each other by a predetermined distance along the longitudinal axis, and The length of the first stack is different from the length of the second stack.

[0017] According to another aspect of the present invention, a method for manufacturing a battery module is provided, the method comprising: Provide a pair of opposing module endplates; A first battery stack and a second battery stack are provided, wherein each of the first battery stack and the second battery stack includes: A series of battery cells stacked along the longitudinal axis, and A pair of stack end plates are arranged at opposite ends of each series of cells; Each pair of stack end plates applies a compressive force along the longitudinal axis to a corresponding series of cells, wherein the pair of stack end plates is in the assembled position when the compressive force on each series of cells is within a predetermined operable range. The stack end plate of the first fuel cell stack is fixed at the corresponding assembly position to limit the length of the first stack; The end plate of the second stack is fixed in the corresponding assembly position to define the length of the second stack; and In the usage position, each of a pair of opposing module end plates is fixedly coupled to a corresponding stack end plate of each of the first and second stacks, such that the module end plates are spaced apart from each other by a predetermined distance along the longitudinal axis.

[0018] In this way, various aspects allow for the easy assembly of battery modules with multiple stacks, applying a consistent compressive force to the cells in each stack. Because each cell experiences compressive force within its operational range, the efficiency of the cells in the battery module is improved. The compressive force remains consistent regardless of any dimensional variations between individual cells or between stacks. The battery module allows for the use of cells with increased tolerance ranges, thereby reducing manufacturing time and minimizing waste that would otherwise result from cells not being of ideal size.

[0019] Furthermore, regardless of any dimensional variations between individual cells or stacks, the battery modules are assembled to a consistent, predetermined size. This allows for more reliable and accurate mounting of the battery modules to vehicle chassis or other components. Manufacturing time and costs are reduced.

[0020] Appropriately, each of the first and second battery stacks can be any battery stack described herein. Each cell can be a prismatic cell. Prismatic cells can include pouch cells located within a frame or housing unit.

[0021] Appropriately, in the assembly position, each pair of end plates can be secured to each other via a pair of intermediate support plates. The pair of end plates and the pair of support plates can cooperate to form a fuel cell stack housing unit.

[0022] By providing a support plate in this way, a battery module is provided, in which the support plate provides structural support for the battery module. The battery module uses a module end plate, eliminating the need for any additional longitudinal components. Assembly is simplified, and manufacturing costs are reduced.

[0023] Appropriately, each support plate may extend along a longitudinal axis between the proximal and distal portions. The proximal portion may have a proximal guiding element. The distal portion may have a distal guiding element.

[0024] Appropriately, in the pre-assembly position, the first end plate of the pair of end plates can contactively engage each proximal guide element. The second end plate of the pair of end plates can contactively engage each distal guide element. The proximal and distal guide elements can each be configured to guide the corresponding first and second end plates toward each other along the longitudinal axis from the pre-assembly position to the assembly position.

[0025] Suitable, each of the first stack endplate and the second stack endplate may include one or more engagement elements. The one or more engagement elements may be arranged to contactively engage the corresponding proximal guide element or the corresponding distal guide element at a pre-assembled position.

[0026] Suitable, each engagement element can be a tab. Each tab can be oriented to protrude from a series of cells in the fuel cell stack.

[0027] In these ways, the stack end plate ensures that compressive force is applied to a series of cells with simple operation. When compressive force is applied, the stack end plate and the series of cells remain aligned.

[0028] Appropriately, in the assembled position, the first stack end plate can be welded to each of the proximal guide elements, and the second stack end plate can be welded to each of the distal guide elements. Therefore, the compressive force can be reliably held in place.

[0029] Suitable, each cell in the series unit may include a peripheral wall. The peripheral wall defines the thickness of each cell in the longitudinal direction of the stack. The peripheral wall may include multiple faces, each oriented along the longitudinal axis. The pair of support plates may abut against the opposite faces of each peripheral wall of the series of cells.

[0030] Suitable, each support plate may include at least one elongated rib. Each of the at least one elongated rib may be configured to at least partially enclose the peripheral wall of at least a portion of the battery cells in a series of battery cells. Each of the at least one elongated rib may be configured to at least partially enclose the peripheral wall of each battery cell in a series of battery cells.

[0031] In these ways, each support plate can be easily fitted onto a series of cells during stack assembly, thereby reducing assembly time. In the pre-assembled position, elongated ribs support the cells within the stack housing unit. During stack assembly, the elongated ribs maintain the alignment of each cell.

[0032] Suitable, each elongated rib may include an adhesive layer. The adhesive layer may be configured to adhere a support plate to the peripheral wall of at least a portion of the cells in a series of cells. The adhesive layer may be configured to adhere the support plate to the peripheral wall of each cell in a series of cells.

[0033] In this way, the adhesive layer further improves the alignment of the cells within the stack. The structural integrity of the stack is enhanced, ensuring a more robust battery module during use.

[0034] Suitablely, each fuel cell stack may include supports stacked with a series of cells. Typically, supports are stacked between pairs of cells in a series of cells. Suitablely, each fuel cell stack may include a series of supports stacked with a series of cells.

[0035] The support components provide structural support for the fuel cell stack.

[0036] Suitablely, the support may include a registration element. The registration element may be configured to be positioned on one of the associated support plates using mutually compatible positioner elements. Suitablely, in the case where the fuel cell stack includes a series of supports, only one of the supports in the series has a registration element.

[0037] Suitable, the support may include at least one pair of registration elements. The pair of registration elements may be disposed on opposite sides of the support to be positioned on the longitudinal surface of a series of cells during stacking.

[0038] Suitablely, the registration element may include a protrusion projecting from the support in the lateral direction. Suitablely, the positioner element may include a aperture through the support plate, the aperture being configured to be positioned in conjunction with a pin receiving position.

[0039] Support members and associated registration elements, or multiple registration elements, ensure that a series of cells are accurately positioned on each support plate. That is, each series of cells is positioned relative to each support plate along the longitudinal axis of the battery stack. A series of cells is precisely registered with the support plates. Therefore, each stack end plate can be mounted onto a series of cells, such that the engagement elements contact the guide elements of the support plates.

[0040] Suitable, the support may include a bore extending through the support. This bore may be a threaded hole. The bore may be oriented to extend vertically through the support.

[0041] In this way, the holes provide an additional means of securing the battery module to the fixing points provided on the support body. The battery module can be attached to fixing points in at least three longitudinal positions, thereby improving the accuracy and robustness of the fixing.

[0042] Appropriately, the operable compressive force is in the range of 10 Newtons to 10,000 Newtons. More appropriately, the operable compressive force is in the range of 10 Newtons to 100 Newtons.

[0043] Appropriately, each series of cells includes at least 10 cells, at least 20 cells, or between 10 and 20 cells.

[0044] Appropriately, each cell in a series of cells includes a pair of cell terminals. The pair of cell terminals may be disposed on the upper surface of the cell.

[0045] Suitable, the battery module may also include a bus assembly. The bus assembly may be configured to be mounted to the battery module for electrical connection to each cell terminal of each stack within the battery module. The bus assembly may include a pair of module terminals for electrical connection to each cell in the battery module.

[0046] Suitable, the first and second module end plates of the pair of module end plates may each extend in a transverse direction perpendicular to the longitudinal axis. Each module end plate may include a series of mounting portions along the transverse direction.

[0047] Appropriately, in the pre-use position, the mounting portion of the first module endplate can contactably engage each of the first stack endplates. The mounting portion of the second module endplate can contactably engage each of the second stack endplates. The mounting portions and stack endplates can each be configured to guide the corresponding first module endplate and the corresponding second module endplate toward each other along the longitudinal axis from the pre-use position to the use position.

[0048] Suitable, each mounting portion may include a slot configured to receive a bonding element of the corresponding endplate in a pre-use position. In the use position, the mounting portion may be soldered to one of the bonding elements.

[0049] Suitable, each mounting portion may include a threaded bolt portion configured to be received in an elongated slot in an engagement element of one of the end plates in a pre-use position. In the use position, the threaded bolt can be clamped onto one of the end plates.

[0050] In these ways, the installation components help guide the assembly of the battery modules, reducing the risk of errors. It simplifies the assembly of the battery modules while ensuring that the battery modules accurately meet the specified dimensions, regardless of any dimensional variations in their stack.

[0051] Each module endplate can be configured to be releasably fastened to a pair of anchor points on a support body. The support body can be, for example, a module enclosure, a vehicle chassis, or a module support frame. The anchor points in the pair can be spaced apart by a predetermined distance.

[0052] Suitable, the battery module may also include at least one third battery stack, said third battery stack comprising: A series of battery cells stacked along the longitudinal axis, and A pair of stack end plates are arranged at opposite ends of the series of cells and configured to be fixed to each other in an assembled position, wherein, in the assembled position, the pair of stack end plates apply a compressive force to the series of cells along the longitudinal axis and define a third stack length; The compressive force applied to the third fuel cell stack is within a predetermined operable range; and The battery module is configured such that, in the position of use, each of a pair of opposing module end plates is also fixedly engaged with a corresponding stack end plate of the third battery stack, such that the module end plates are spaced apart from each other by a predetermined distance along the longitudinal axis.

[0053] Appropriately, the third stack length may differ from at least one of the following: the first stack length or the second stack length.

[0054] In this way, the battery module can be adapted to different configurations. The battery module can be expanded to include three, four or more stacks, each with a different stacking length.

[0055] Appropriately, the method of manufacturing the battery module may include a second stack length different from the first stack length.

[0056] Appropriately, the method may include the following steps: providing a corresponding intermediate pair of support plates for each of the first and second fuel cell stacks, such that each pair of stack end plates and the corresponding pair of support plates cooperate to form a fuel cell stack housing unit.

[0057] Appropriately, the method steps for securing the end plate of the corresponding fuel cell stack in the assembly position may include welding the end plate to an associated support plate.

[0058] Suitable, the method may include the following steps: in a pre-assembly position, contactally engaging each of a pair of end plates with a distal guide element on each of a first and second fuel cell stack, or contactally engaging with a proximal guide element on each of the first and second fuel cell stacks. Once contactally engaged, the corresponding first and second end plates are guided along their longitudinal axes toward each other from the pre-assembly position to the assembly position.

[0059] Suitablely, the method may include: each of the first and second battery stacks includes a support member stacked with a corresponding series of battery cells. Prior to the step of applying compressive force to the corresponding series of battery cells along the longitudinal axis using each pair of stack end plates, there may also be additional steps including: positioning each support member with an associated support plate. Attached Figure Description

[0061] The example will now be described further with reference to the accompanying drawings, in which: Figure 1 A perspective view of an example battery module is shown according to one aspect; Figure 2 It shows Figure 1 A perspective view of an example battery stack for a battery module; Figure 3 It shows Figure 1 A close-up perspective view of a portion of the battery module; Figure 4 It shows Figure 1 A top view of the battery module, in which the fuel cell stack is mounted to the module end plate in an assembly position; Figure 5A It shows Figure 2 Example support for the fuel cell stack; Figure 5B It shows Figure 2 Longitudinal cross-sectional view of the fuel cell stack; Figure 6A It shows Figure 2 The cross-sectional view of the fuel cell stack, and Figure 6B It shows Figure 2 A close-up cross-sectional view of the fuel cell stack; Figure 7A A perspective view of an example battery stack and threaded bolts according to a second example battery module is shown; Figure 7B It shows Figure 7A Examples and one of its module endplates; and Figure 8 It shows Figure 7B The lower perspective view of the battery module. Detailed Implementation

[0063] Some terms used in the following description are for convenience only and are not restrictive. The terms “lower,” “upper,” “longitudinal,” “lateral,” and “transverse” indicate directions referenced in the drawings and are relative to the parts described during assembly and installation. The terms “inner,” “inward,” “outer,” and “outward” refer to directions toward and away from the specified centerline or geometric center (e.g., central axis) of the described element, respectively, and their particular meanings become apparent from the context of the specification.

[0064] Furthermore, as used herein, the term "installation" is intended to include both a direct connection between two components without the insertion of any other component therebetween, and an indirect connection between components (with one or more other components inserted therebetween). The term includes the words specifically mentioned above, their derivatives, and words with similar meanings.

[0065] Furthermore, unless otherwise stated, the use of ordinal adjectives (such as “first,” “second,” “third,” etc.) merely indicates different instances of similar objects referred to, and does not imply that the objects described must be in a given order (whether in time, space, ranking, or any other way).

[0066] Now for reference Figures 1 to 6B The image shows a first example battery module 100. The battery module 100 includes a pair of opposing module end plates 160a and 160b spaced apart from each other along a longitudinal axis 102. The battery module 100 also includes a first battery stack 110a, a second battery stack 110b, and a third battery stack 110c.

[0067] Special Reference Figure 2 The diagram illustrates a first battery stack 110a, representing each of the first, second, and third battery stacks 110a and 110c. The battery stack 110a includes a series of cells 112 stacked along a longitudinal axis 102, and a pair of end plates 130a, 130b arranged at opposite ends of the series of cells 112 and configured to be fixed to each other in the assembly position. In the example battery module, each series of cells has 12 prismatic cells.

[0068] At the assembly position, a pair of end plates 130a, 130b apply compressive force to a series of cells 112 along the longitudinal axis 102. The corresponding pair of end plates 130a, 130b also define the stack length of each stack 110a, 110b, 110c. The compressive forces applied to the first stack 110a, the second stack 110b, and the third stack 110c are each within a predetermined operable range. That is, the compressive forces are within the operable compressive force range specified by the cell manufacturer.

[0069] The battery module 100 is configured such that each of a pair of opposing module end plates 160a, 160b is fixedly engaged in a usage position with a corresponding stack end plate 130a, 130b of each of the first stack 110a, the second stack 110b, and the third stack 110c. In the usage position, the module end plates 160a, 160b are spaced apart from each other by a predetermined distance along the longitudinal axis 102, and at least the first stack length is different from the second stack length. In this example, the first stack length is different from both the second and third stack lengths, specifically as follows: Figure 4 As shown.

[0070] In the assembly position, each pair of end plates 130a and 130b of the three fuel cell stacks 110a, 110b, and 110c are fixed to each other via a central pair of support plates 140a and 140b. Thus, each pair of end plates 130a and 130b and each pair of support plates 140a and 140b cooperate to form a fuel cell stack enclosure unit. The fuel cell stack enclosure unit surrounds the periphery of each fuel cell stack 110a, 110b, and 110c.

[0071] Each cell 112 includes a peripheral wall disposed perpendicular to the longitudinal axis 102. A pair of support plates 140a, 140b abut against the opposite surfaces of each peripheral wall. The peripheral wall defines the thickness of each cell in the longitudinal direction of the stack. This thickness is the nominal thickness, conforming to tolerance requirements, before any compressive force is applied to the cells 112 within the stacks 110a, 110b, 110c.

[0072] The housing unit extends longitudinally and laterally around the respective cell 112. The upper surface of each cell 112 remains exposed, making the cell terminal 116 accessible for electrical connection.

[0073] Each support plate 140a, 140b extends along the longitudinal axis 102 between a proximal portion 142 and a distal portion 141. The proximal portion 142 has a proximal guide element 144. The distal portion 141 has a distal guide element 144. Additionally, each of the first stack end plate 130a and the second stack end plate 130b includes a pair of engaging elements 132. The engaging elements 132 are spaced apart from each other in the lateral direction such that they are arranged on opposite edges of the respective stack end plates 130a, 130b.

[0074] The engagement element 132 is positioned to contact and engage the corresponding proximal guide element 144 or the distal guide element 144 at a pre-assembly position. The pre-assembly position corresponds to the position where the end plates 130a, 130b contact the stack housing unit but do not apply compressive force to the series of cells. The proximal guide element 144 and the distal guide element 144 are each configured to guide the corresponding first end plate 130a and the corresponding second end plate 130b toward each other along the longitudinal axis 102 from the pre-assembly position to the assembly position.

[0075] In this example, each guide element 144 includes an inwardly facing longitudinal surface. Each engagement element 132 is a tab oriented such that when the end plates 130a, 130b engage with a series of cells, each tab protrudes away from the series of cells. Thus, when the end plates 130a, 130b move to the assembly position, each longitudinal surface abuts against the outer surface of the engagement element 132 to limit the corresponding lateral movement.

[0076] In the assembled position, the first stack end plate 130a is welded to each of the proximal guide elements 144, and the second stack end plate 130b is welded to each of the distal guide elements 144. That is, a welding point 136a is provided between each guide element 144 and the engagement element 132 to secure the stack end plates 130a, 130b in the assembled position.

[0077] A first module end plate 160a and a second module end plate 160b of a pair of module end plates each extend in a transverse direction perpendicular to the longitudinal axis 102. Each of the first module end plate 160a and the second module end plate 160b includes a series of mounting portions 162 spaced apart in the transverse direction. In this example, the first mounting portion 162 includes an outward-facing surface. This surface is provided on a vertical plate at each transverse end of the module end plates 160a, 160b. The second mounting portion 162 includes an elongated slot 164 passing through the module end plates 160a, 160b.

[0078] Thus, each module end plate 160a, 160b is configured to guide the stack end plates 130a, 130b of each of the stacks 110a, 110b, 110c with different stack lengths from the pre-use position to the use position.

[0079] In the pre-use position, the mounting portion 162 of the first module end plate 160a contacts and engages with each of the first stack end plates 130a. The mounting portion 162 of the second module end plate 160b contacts and engages with each of the second stack end plates 130b. The mounting portions 162 and the stack end plates are each configured to guide the corresponding first module end plate 160a and the corresponding second module end plate 160b toward each other along the longitudinal axis from the pre-use position to the use position.

[0080] Specifically, when the corresponding module end plate 160a moves from the pre-use position to the use position, the outward-facing surface of each first mounting portion 162 abuts against the engagement element 132 of the fuel cell stacks 110a, 110c. Lateral movement of the module end plate 160a is restricted. Furthermore, when the module end plate 160a moves from the pre-use position to the use position, the elongated slot 164 of each second mounting portion 162 abuts against the engagement element 132 of the fuel cell stacks 110a, 110b, 110c. Lateral movement of the module end plate 160a is restricted.

[0081] like Figure 4 As specifically shown, in each case, the usage position can be adapted to a variable stack length because at least one component of each abutment (i.e., one of each abutment engagement element 132 and mounting portion 162) extends along the longitudinal axis 102. For the shortest length stack 110b, the module end plates 160a, 160b are guided only a short distance by the stack 110b engagement element 132 until they are in the usage position. For the longest length stack 110c, the module end plates 160a, 160b are guided a greater distance by the stack 110b engagement element 132 until they are in the usage position. For a medium length stack 110a, the module end plates 160a, 160b are guided a medium distance by the stack 110b engagement element 132 until they are in the usage position.

[0082] In their respective locations, each stack end plate 130a, 130b is welded to the corresponding module end plates 160a, 160b. For example... Figure 3 As shown in the figure, a solder point 136b is provided between each joining element 132 and the mounting portion 162 to fix the module end plates 160a, 160b in the assembly position.

[0083] Each module end plate 160a, 160b is configured to be releasably fastened to a pair of fixing points provided on a support body (e.g., module housing, vehicle chassis, or module support frame). In this example, the module end plates 160a, 160b include bores for receiving fasteners (e.g., bolts). Because the module end plates 160a, 160b are fastened to the fuel cell stacks 110a, 110b, 110c at predetermined distances, the battery module 100 can be reliably and accurately fixed to the fixing points on the support body spaced at predetermined distances.

[0084] Now for reference Figure 5AThe diagram shows a support member 120. Each battery stack 110a, 110b, 110c includes a support member 120 stacked with a corresponding series of battery cells 112. The support members 120 are stacked between a pair of battery cells located at the midpoint of the series of battery cells. The support member 120 is a rigid plate with a plurality of grooves 123 on its outer surface. The grooves 123 reduce the weight of the support member 120 while maintaining its rigidity.

[0085] The support member 120 includes a series of registration elements 121. The registration elements 121 are configured to be positioned on one of the associated support plates 140a, 140b using mutually compatible locator elements 146. In this example, the registration elements 121 are located on opposite sides of the support member 120 to be positioned on the longitudinal surface of a series of cells 112 during stacking. Each registration element 121 is in the form of a protrusion projecting from the support member 120 in the lateral direction. The protrusion is sized to receptively position itself within the locator element 146 in the corresponding support plate 140a, 140b. In this example, each locator element 146 is a through-hole (within) of the support plate 140a, 140b. Figure 6A (as specifically shown in the text).

[0086] Thus, before the assembly of the fuel cell stacks 110a, 110b, and 110c is completed, each series of cells 112 can be positioned using support plates 140a and 140b. Support member 120 ensures that the series of cells 112 is centered along the longitudinal axis 102 via each support plate 140a and 140b. The series of cells 112 is precisely aligned with the support plates 140a and 140b. Therefore, each stack end plate 130a and 130b can be mounted to the series of cells 112, such that the engagement element 132 contacts and engages the guide element 144 of the support plates 140a and 140b.

[0087] The support member 120 includes holes 122. The holes 122 are oriented to extend vertically through the support member 120. The holes 122 provide an additional means of securing the battery module 100 to fixing points located on the support body (e.g., module housing, vehicle chassis, or module support frame). In conjunction with the registration element 121, the spacing between the support member 120 and the module end plates 160a, 160b is also reliably and accurately set. Furthermore, one or each hole 122 can provide a reference as the center position of each battery stack. Correspondingly, one or each hole 122 can provide a reference as the center longitudinal position on the battery module. For example, the holes 122 can be used as a reference for positioning a cover fixed to the battery module.

[0088] Now for reference Figure 6A and Figure 6BThe diagram shows a cross-sectional view of the fuel cell stack 110a, including the battery cell 112 and the support plate 140a. The support plate 140a includes a pair of elongated ribs 148, specifically an upper elongated rib 148 and a lower elongated rib 148. Each elongated rib 148 extends substantially along the length of the support plate 140a.

[0089] Each elongated rib 148 is configured to at least partially wrap around the peripheral wall of a series of cells 112. Thus, when the stack 110a is assembled, the support plate 140a is fitted onto the series of cells. In the pre-assembled position, the elongated ribs 148 support the cells 112 within the stack 110a housing unit and maintain the alignment of each cell 112.

[0090] Each elongated rib 148 includes an adhesive layer 150. The adhesive layer 150 is configured to adhere the support plate to the peripheral wall of the cell in a series of cells. Therefore, the adhesive layer 150 further improves the alignment of the cell 112 within the stack 110a. The structural integrity of the stack 110a is improved, ensuring that the battery module 100 is more robust in use.

[0091] The battery module 100 can be assembled using one method.

[0092] In the first step of this method, a pair of opposing module end plates 160a and 160b are provided.

[0093] In the second step of the method, a first battery stack 110a, a second battery stack 110b, and a third battery stack 110c are provided. Each of the battery stacks 110a, 110b, and 110c includes a series of cells 112 stacked along a longitudinal axis 102, and a pair of stack end plates 130a, 130b disposed at opposite ends of each series of cells 112. Furthermore, for the example battery module 100, the method includes providing a corresponding intermediate pair of support plates 140a, 140b for each battery stack 110a, 110b, and 110c. Each pair of stack end plates 130a, 130b and the corresponding pair of support plates 140a, 140b cooperate to form a stacked housing unit. The stacked housing unit surrounds the periphery of the battery stack, wherein the periphery extends longitudinally and laterally around the battery stack.

[0094] In the third step of this method, the support member 120 is positioned together with the support plates 140a and 140b of each battery stack 110a, 110b, and 110c. The support member 120 is associated with the corresponding series of battery cell stacks, as referenced here. Figure 5A and Figure 5B As stated above.

[0095] In the fourth step of the method, the first end plate 130a of each pair of end plates is contactively engaged with the distal guide element 144 on each support plate 140a, 140b in the pre-assembly position. Furthermore, in the pre-assembly position, the second end plate 130b of each pair of end plates is contactively engaged with the proximal guide element 144 on the support plates 140a, 140b.

[0096] In the fifth step of the method, a compressive force is applied to a corresponding series of cells along the longitudinal axis 102 using each pair of end plates 130a, 130b. During this process, the distal and proximal guide elements 144 guide the first end plate 130a and the second end plate 130b toward each other along the longitudinal axis 102, from the pre-assembly position to the assembly position. That is, the end plates 130a, 130b are guided toward each other until the compressive force on each series of cells 112 is within a predetermined operable range.

[0097] In the sixth step of the method, the end plates 130a and 130b of the first fuel cell stack 110a are fixed in their respective assembly positions to define a first stack length. Furthermore, the end plates 130a and 130b of the second fuel cell stack 110b are fixed in their respective assembly positions to define a second stack length. Furthermore, the end plates 130a and 130b of the third fuel cell stack 110c are fixed in their respective assembly positions to define a third stack length. The second stack length is different from both the first and third stack lengths. Specifically, the end plates 130a and 130b of each fuel cell stack 110a, 110b, and 110c are fixed in their assembly positions by welding the end plates 130a and 130b to their associated support plates 140a and 140b.

[0098] In the seventh step of the method, in the pre-use position, each of a pair of opposing module end plates 160a, 160b is mounted to fuel cell stacks 110a, 110b, 110c. In the pre-use position, the engagement element 132 of each fuel cell stack 110a, 110b, 110c is contactively engaged with the mounting portion 162 of the corresponding module end plate 160a, 160b. The module end plates 160a, 160b are guided to the use position by the engagement element 132. In the use position, the module end plates are spaced apart from each other by a predetermined distance along the longitudinal axis. The module end plates 160a, 160b are then secured to the use position by welding each mounting portion 162 to one or more corresponding engagement elements 132.

[0099] Now for reference Figures 7A to 8 The second example battery module 200 is shown. Figure 7A The image shows battery stacks 210a, 210b, and 210c of battery module 200, with only the threaded bolts 266 of module end plate 260 visible. Figure 7B andFigure 8 In the diagram, threaded bolt 266 is shown mounted on its module end plate 260.

[0100] The second example battery module 200 is identical to the first example battery module 100, except that the way each stack 210a, 210b, 210c is joined and secured to its module end plate 260 differs. Features identical to those in the previous example have the same numbers, except that the first number is “2” instead of “1”.

[0101] Accordingly, the battery module 200 includes a pair of opposing module end plates 260 spaced apart from each other along the longitudinal axis 202. The battery module 200 includes a first battery stack 210a, a second battery stack 210b, and a third battery stack 210c. Each battery stack 210a, 210b, 210c includes a series of battery cells 212 stacked along the longitudinal axis 202, and a pair of stack end plates 230a, 230b disposed at opposite ends of the series of battery cells 212.

[0102] A pair of end plates 230a and 230b are configured to be fixed to each other in an assembled position, wherein, in the assembled position, the pair of end plates 230a and 230b apply compressive force along the longitudinal axis 202 to a series of cells 212 and define the stack length of each stack 210a, 210b, 210c. The end plates 230a and 230b are fixed to each other via intermediate support plates 240a and 240b. The compressive force applied to each stack 210a, 210b, 210c is within a predetermined operable range.

[0103] The battery module 200 is configured such that each of a pair of opposing module end plates 260 is fixedly engaged in a usage position with a corresponding stack end plate 230a, 230b of each stack 210a, 210b, 210c. In the usage position, the module end plates 260 are spaced apart from each other along the longitudinal axis 202 by a predetermined distance, while the first stack length is different from the second stack length.

[0104] Each of the stacks 210a, 210b, and 210c includes a bonding element 232 on the stack end plates 230a and 230b, which is fixed in the assembly position to the guide element 244 of the support plates 240a and 240b, as described herein with respect to the battery module 100.

[0105] The module end plate 260 includes a series of threaded bolts 266 fixed to it. Each threaded bolt 266 extends vertically from its upper end to its lower end. The upper end is fixed to the upper edge of the module end plate 260, such that the threaded bolt 266 is stationary relative to the module end plate 260. The lower end of each threaded bolt 266 includes a mounting portion of the module end plate 260.

[0106] Each stack end plate 230a, 230b also includes a transverse shelf 233. Each transverse shelf 233 has at least one elongated slot 234 extending at least in the longitudinal direction. The elongated slot 234 is configured to receive a mounting portion of a threaded bolt 266 fixed to the module end plate 260.

[0107] The mounting portion moves freely along the longitudinal axis 202 within the elongated slot 234. In this way, the module end plate 260 can be moved relative to each stack end plate 230a, 230b from a pre-use position (where the mounting portion is received in the elongated slot 234) to a use position (where a pair of module end plates 260 are spaced apart by a predetermined distance).

[0108] With the module end plates 260 spaced apart by a predetermined distance, each module end plate 260 is fixed to each corresponding stack end plate 230a, 230b. In the example shown, each module end plate 260 is first fixed by bolts fastened to the mounting portion of each threaded bolt 266 and clamped to the transverse shelf 233.

[0109] In addition, the module end plate 260 also includes a mounting portion 262 in the form of a vertically oriented additional elongated slot 264 for receiving and abutting against the engagement elements 232 of one or more stacks 210a, 210b, 210c. Thus, each module end plate 260 is also secured to each corresponding stack end plate 230a, 230b via solder points 236b within each elongated slot 264.

[0110] It should be understood that, depending on the requirements of the battery module, one or both of two methods can be used to secure the module end plate to each corresponding stack end plate. The module end plate can be secured by clamping threaded bolts to a transverse shelf, or by welding engagement elements into an elongated slot, or by clamping threaded bolts to a transverse shelf and welding engagement elements into an elongated slot. Within the scope of this invention, additional securing devices not described herein can also be provided to allow each module end plate to engage with its corresponding stack end plate in a pre-use position and then be guided along the longitudinal axis to the use position for securing.

[0111] In the description and claims of this specification, the words “comprising” and “containing” and their variations mean “including but not limited to”, and they are not intended (and will not) exclude other parts, additives, ingredients, wholes, or steps. In the description and claims of this specification, the singular includes the plural unless the context requires otherwise. In particular, when the indefinite article is used, the specification should be understood to consider both the plural and the singular unless the context requires otherwise.

[0112] Features, elements, characteristics, or groups described in connection with specific aspects, embodiments, or examples of the invention should be understood to be applicable to any other aspect, embodiment, or example described herein, unless incompatible therewith. All features disclosed in this specification (including any appended claims, abstract, and drawings) and / or all steps of any disclosed method or process can be combined in any combination, unless at least some of these features and / or steps are mutually exclusive combinations. The invention is not limited to the details of any of the foregoing embodiments. The invention covers any novel feature or any novel combination of features disclosed in this specification (including any appended claims, abstract, and drawings), or any novel step or any novel combination of steps in any disclosed method or process.

[0113] Readers are advised to note all papers and documents related to this application, submitted concurrently with or prior to this specification, and made publicly available together with this specification, the contents of which are incorporated herein by reference.

Claims

1. A battery module comprising: a pair of opposing module end plates spaced apart from each other along a longitudinal axis; a first stack; and a second stack; wherein each of the first stack and the second stack comprises: a series of cells stacked along the longitudinal axis, and a pair of stack end plates arranged at opposite ends of the series of cells and configured to be secured to each other in an assembled position, wherein in the assembled position the pair of stack end plates exerts a compression force on the series of cells along the longitudinal axis and defines a stack length of the respective stack; wherein the compression force exerted to the first stack and the compression force exerted to the second stack are each within a predetermined operable range; and wherein the battery module is configured such that each of the pair of opposing module end plates is fixedly engaged with one corresponding stack end plate of each of the first stack and the second stack in a use position, such that: - the module end plates are spaced apart from each other along the longitudinal axis by a predetermined distance, and - the first stack length is different from the second stack length.

2. The battery module of claim 1, wherein, In the assembled position, each pair of stack end plates is secured to each other via an intermediate pair of support plates such that the pair of stack end plates and the pair of support plates cooperatively form a stack housing unit.

3. The battery module of claim 2, wherein, Each cell of the series of cells comprises a peripheral wall defining a thickness of the cell in a longitudinal direction of the stack, and wherein the pair of support plates abut opposite faces of each peripheral wall.

4. The battery module of claim 2 or 3, wherein, Each support plate extends along the longitudinal axis between: a proximal portion of a proximal guide element having a proximal end; and a distal portion of a distal guide element having a distal end; wherein in a pre-assembled position, a first stack end plate of the pair of stack end plates contactingly engages each of the proximal guide elements and a second stack end plate of the pair of stack end plates contactingly engages each of the distal guide elements; and wherein the proximal guide elements and the distal guide elements are each configured to guide the corresponding first stack end plate and the corresponding second stack end plate towards each other along the longitudinal axis from the pre-assembled position to the assembled position.

5. The battery module of claim 4, wherein, Each of the first stack end plate and the second stack end plate comprises one or more engagement elements arranged to contactingly engage the corresponding proximal guide element or distal guide element in the pre-assembled position.

6. The battery module of claim 5, wherein, Each engagement element is a tab projecting away from the series of cells in the stack.

7. The battery module of claim 4 or 5, wherein, In the assembled position, the first stack end plate is welded to each of the proximal guide elements and the second stack end plate is welded to each of the distal guide elements.

8. The battery module of any one of claims 2-7, wherein, Each support plate comprises at least one elongate rib configured to at least partially wrap around a peripheral wall of at least a portion of the cells in the series of cells.

9. The battery module of claim 8, wherein, The elongate rib comprises an adhesive layer configured to adhere the support plate to the peripheral wall of at least a portion of the cells in the series of cells.

10. The battery module of any one of claims 2-9, wherein, Each stack comprises a support stacked with the series of cells, the support being generally stacked between a pair of cells in the series of cells.

11. The battery module of claim 10, wherein, The support includes a registration element, and wherein the registration element is configured to be positioned on one of the associated support plates with a mutually compatible positioner element.

12. The battery module of claim 11, wherein, The registration element includes a pin protruding from the support in a transverse direction, and the positioner element includes an aperture through the support plate, the aperture being configured to be positioned in receiving relation with the pin.

13. The battery module of claim 1, wherein, The predetermined operable range of compression forces is from 1 Newton to 10000 Newtons.

14. The battery module of any one of claims 1-13, wherein, The first and second module end plates of the pair of module end plates each extend in a transverse direction perpendicular to the longitudinal axis, and each include a series of mounting portions along the transverse direction.

15. The battery module of claim 14, wherein, In a pre-use position, the mounting portions of the first module end plate contactingly engage each of the first stack end plates, and the mounting portions of the second module end plate contactingly engage each of the second stack end plates, and wherein the mounting portions and the stack end plates are each configured to guide the corresponding first and second module end plates toward each other along the longitudinal axis from the pre-use position to the use position.

16. The battery module of claim 14 or 15, wherein, Each mounting portion includes a slot configured to receive the engagement element of the corresponding stack end plate in the pre-use position.

17. The battery module of any one of claims 14-16, wherein, Each mounting portion includes a threaded bolt portion configured to be received in an elongated slot in one of the stack end plates in the pre-use position.

18. The battery module of any one of claims 1-17, wherein, Each module end plate is configured to be releasably fastened to a pair of fixation points provided on a support body, such as a module enclosure, a vehicle chassis, or a module support frame, wherein the fixation points of the pair of fixation points are spaced apart by the predetermined distance.

19. The battery module of any one of claims 1 to 18, further comprising: at least one third electrical stack comprising: a series of electrical cells stacked along the longitudinal axis, and a pair of stack end plates arranged at opposite ends of the series of electrical cells and configured to be fixed to each other in the assembled position, wherein in the assembled position the pair of stack end plates exert a compression force on the series of electrical cells along the longitudinal axis and define a third stack length; wherein the compression force exerted to the third electrical stack is within the predetermined operable range; and wherein the battery module is configured such that in the use position each of the pair of opposing module end plates is also fixedly engaged with one corresponding stack end plate of the third electrical stack, such that: - the module end plates are spaced apart from each other along the longitudinal axis by the predetermined distance.

20. The battery module of claim 19, wherein, The third stack length is different from at least one of: the first stack length or the second stack length.

21. A method of manufacturing a battery module, the method comprising: providing a pair of opposing module end plates; providing a first electrical stack and a second electrical stack, wherein each of the first and second electrical stacks comprises: a series of electrical cells stacked along a longitudinal axis, and a pair of stack end plates arranged at opposite ends of each series of electrical cells; applying a compressive force along the longitudinal axis to the respective series of cells using each pair of stack end plates, wherein the pair of stack end plates is in an assembled position when the compressive force on each series of cells is within a predetermined operable range; securing the stack end plates of the first stack in corresponding assembled positions to define a first stack length; securing the stack end plates of the second stack in corresponding assembled positions to define a second stack length; and in the use position, fixedly joining each of a pair of opposing module end plates to one corresponding stack end plate of each of the first stack and the second stack such that the module end plates are spaced apart from each other along the longitudinal axis by a predetermined distance.

22. The method of claim 21, wherein, The method includes providing each of the first stack and the second stack with a respective intermediate pair of support plates such that each pair of stack end plates and the respective pair of support plates cooperatively form a stack enclosure unit.

23. The method of claim 22, wherein, The step of securing the stack end plates of the respective stack in the assembled position includes welding the stack end plates to the associated support plates.

24. The method of claim 22 or 23, further comprising the steps of: in a pre-assembled position, fixedly joining each of the pair of stack end plates in contact with a distal end guide element on each of the first stack and the second stack, or in contact with a proximal end guide element on each of the first stack and the second stack; and guiding the corresponding first stack end plate and the corresponding second stack end plate along the longitudinal axis toward each other from the pre-assembled position to the assembled position.

25. The method of any one of claims 21 to 24, wherein, each of the first stack and the second stack includes a support stacked with a respective series of cells; and wherein the method, prior to applying a compressive force along the longitudinal axis to the respective series of cells using each pair of stack end plates, further includes the step of: positioning each support with an associated support plate.

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