CN114788081B

CN114788081B - Battery cell carrier, battery module and method for assembling the same

Info

Publication number: CN114788081B
Application number: CN202080085982.2A
Authority: CN
Inventors: V.阿隆索阿罗约; W.杰普; O.斯特拉特
Original assignee: Dyson Technology Ltd
Current assignee: Dyson Technology Ltd
Priority date: 2019-10-18
Filing date: 2020-09-16
Publication date: 2024-09-10
Anticipated expiration: 2040-09-16
Also published as: GB2588390A; GB201915080D0; CN114788081A; WO2021074574A1; GB2588390B

Abstract

A cell carrier (1100) for holding a plurality of cells (420) has an upper surface (1120 a) and a lower surface (1120 b). The cell carrier (1100) has a plurality of openings (1140) extending between the upper surface (1120 a) and the lower surface (1120 b). The cell carrier (1100) has a recess (1160) in the upper surface (1120 a) for receiving an adhesive. Each opening (1140) has a wall (1130) with a hole (1170) fluidly connecting the opening (1140) and the recess (1160) such that adhesive inserted into the recess (1160) flows from the recess (1160) through the hole (1170) into the opening (1140).

Description

Battery cell carrier, battery module and method for assembling the same

Technical Field

The present invention relates to batteries, and in particular, but not exclusively, to battery modules and battery packs comprising such battery modules, as well as battery cell carriers. In particular, but not exclusively, the invention relates to a battery module, a battery pack and a battery cell carrier for an electric vehicle.

Background

The battery is an indispensable part of the electric vehicle. In some cases, a battery pack including a battery and a frame may form at least a portion of an electric vehicle structure. Maintenance of the battery pack in an electric vehicle, particularly an electric vehicle, can be frequent and can be challenging due to the location of the battery pack in the electric vehicle. Accordingly, it may be desirable to provide a practical and reliable battery pack for an electric vehicle that is easy to manufacture and maintain. Reducing the weight of the battery pack may also be a desire to improve performance in the electric vehicle arts.

Disclosure of Invention

According to a first aspect of the present invention, there is provided a cell carrier for holding a plurality of cells, the cell carrier comprising an upper surface and a lower surface, a plurality of openings extending between the upper surface and the lower surface, each opening for receiving one of the plurality of cells; and a recess in the upper surface for receiving adhesive, wherein the wall of each opening includes a hole fluidly connecting the opening to the recess such that adhesive inserted into the recess flows from the recess into the opening through the hole.

In this way, when the battery cell is located in the battery cell carrier, the adhesive may be inserted into the recess and may contact the battery cell wall, thereby securing the battery cell in a fixed position within the battery cell carrier. The use of recesses in fluid communication with the plurality of openings via respective apertures may allow a single adhesive injection device to be used to secure a plurality of battery cells within the battery cell carrier. This can improve the speed and efficiency of manufacturing a battery module including such a battery cell carrier. Furthermore, since the adhesive is in contact with the cell walls within the cell carrier, less adhesive may be used to achieve similar cohesion when compared to cell carriers where adhesive is used on the outer surface or not in the recess.

Each aperture may extend upwardly to the upper surface.

In this way, each aperture may provide an open channel between the recess and the opening. The open channels may reduce the resistance to adhesive flow therethrough, thereby reducing the risk of adhesive blockage or clogging. A greater adhesive flow rate may also be achieved, thereby reducing the time to manufacture a battery module including such a battery cell carrier.

The battery cell carrier may be planar and the lower surface may be flat. For example, the lower surface may be substantially free of recesses or through holes, except for the openings.

Having a recess on only the upper surface may prevent the adhesive from overflowing the cell carrier. Furthermore, the absence of a recess in the lower surface may preserve the structural integrity of the cell carrier such that it may provide sufficient support and structure to hold the cells and, in some examples, the corresponding bus bars in place.

Each opening in the battery cell carrier may be configured to receive a respective cell therethrough.

Having one opening per cell may allow the opening to be formed around the shape of one cell, which may provide enhanced support for each cell in the battery cell carrier.

Each opening may comprise an annular ridge, for example at least partially defining a respective one of the openings.

The annular ridge may provide support for the unit and ensure that the opening is not much larger than the size of the unit within manufacturing tolerances.

The annular ridge may surround a respective one of the openings.

Having annular ridges around the respective openings may prevent adhesive from flowing down the sides of the battery cells that may be received in the battery cell carrier. This may reduce the amount of adhesive required, thereby reducing the weight and cost of manufacturing a battery module including the battery cell carrier.

The ridge may be located between the aperture and the lower surface.

This may prevent the annular ridge from affecting the introduction of adhesive into the recess and/or opening.

The ridge may be arranged to contact a battery cell receivable in the corresponding opening.

In this way, the annular ridge may be configured to secure a battery cell receivable within its respective opening.

The ridge may be arranged to retain the adhesive within the opening.

In this way, the adhesive is not wasted by leakage, and the battery cells are not covered with an excessive amount of adhesive, which can reduce cost and weight. In addition, excessive amounts of adhesive may affect thermal control of the battery cells.

The battery cell carrier may be configured to hold the battery cells such that an end of each battery cell is at least partially exposed through an upper surface of the battery cell carrier.

In this way, the adhesive does not interfere with the electrical connection between the cells held by the cell carrier and the associated bus bars or other electrical connection mechanisms used to connect the cells.

The at least one opening may be a virtual opening configured to block insertion of the battery cell therethrough, the virtual opening being adjacent to and in fluid communication with the recess.

The virtual openings may be used to maintain consistent adhesive fluid characteristics for openings adjacent to the virtual openings during adhesive introduction and/or injection.

The battery cell carrier may include at least one mounting feature for mounting circuitry of the battery management system to the battery cell carrier.

This may allow a corresponding battery management system circuit to be collocated with a corresponding cell group for monitoring and controlling parameters of the cell group.

The battery cell carrier may include at least one first securing feature for engaging with at least one second securing feature of the bus bar to align the bus bar relative to the battery cell carrier.

This may ensure accurate positioning of the bus bar relative to the battery cells, which will be held by the battery cell carrier for electrical connection.

The at least one first securing feature may comprise an upstanding projection and the at least one second securing feature may comprise a securing aperture for engagement with the at least one upstanding projection.

This may ensure accurate positioning of the bus bar relative to the battery cells to be held by the battery cell carrier for electrical connection and may also prevent the bus bar from being lowered onto the battery cell carrier in an incorrect position and potentially damaging the battery cells held therein.

The upstanding projections may deform to secure the bus bar to the cell carrier.

The deformed portion may provide a reliable way of fixing the bus bar to the cell carrier.

The cell carrier may include a plurality of recesses for receiving an adhesive, each recess being fluidly connected to the plurality of openings by a respective aperture.

Providing a plurality of such recesses for the cell carrier may allow a large number of cells to be securely fastened to the cell carrier using an adhesive.

According to a second aspect of the present invention, there is provided a battery module including a plurality of battery cells, a battery cell carrier holding the plurality of battery cells, and an adhesive, the battery cell carrier including an upper surface and a lower surface; a plurality of openings extending between the upper surface and the lower surface, each opening receiving one of the plurality of battery cells; and a recess in the upper surface for receiving an adhesive; wherein the wall of each opening includes a hole fluidly connecting the opening to the recess such that the adhesive extends from the recess, through the hole and into the opening, and the adhesive contacts the respective cell such that the cell is retained in the cell carrier by the adhesive.

In this way, the adhesive may be inserted into the recess and may contact the plurality of battery cells, thereby securing the battery cells in a fixed position within the battery cell carrier. The use of recesses in the upper surface in fluid communication with the plurality of openings through the apertures may allow for the use of a single adhesive injection device to secure the plurality of battery cells within the battery cell carrier. This can improve the speed and efficiency of manufacturing a battery module including such a battery cell carrier. Further, because the adhesive is able to enter the opening and contact the surface of each cell within the opening, less adhesive may be used to achieve similar cohesion as compared to cell carriers where adhesive is used on the outer surface or not in the opening.

The battery cell carrier may be a battery cell carrier as described above.

The battery module may include a bus bar, the cell carrier may include at least one first securing feature, and the bus bar may include at least one second securing feature, wherein the at least one first securing feature engages with the at least one second securing feature to align the bus bar relative to the cell carrier.

The at least one first securing feature may comprise an upstanding projection and the at least one second securing feature may comprise a securing aperture that engages the at least one upstanding projection.

Having corresponding fixing holes and fixing features can ensure that the bus bar is properly positioned and can increase manufacturing speed.

The at least one first securing feature may have a deformed portion to secure the bus bar to the battery carrier.

The cell walls of each cell may include an annular groove that holds adhesive inserted through a hole in the wall of the opening. The annular groove may be located at or below the level of the recess. This may result in increased adhesive flow rate and/or improved adhesion due to the additional surface area provided by the annular groove.

This may prevent the adhesive from overflowing and/or being excessively inserted, thereby allowing the adhesive to be more effectively used and allowing a reduced amount of the adhesive to be used to fix the battery cells, which may otherwise affect the weight and cost of the battery module and the battery pack.

For each opening accommodating a battery cell, the respective wall of the opening and the respective cell wall may define an annular cavity for accommodating an adhesive between the battery cell and the battery cell carrier. In this way, space is advantageously provided for the adhesive to collect the adhesive and reliably adhere the battery cells to the cell carrier.

The battery module may be used in an electric vehicle.

According to a third aspect of the present invention, there is provided an electric vehicle including the battery module as described above.

According to a fourth aspect of the present invention, there is provided a method of assembling a battery module including a battery cell carrier and a plurality of battery cells, the battery cell carrier including: an upper surface and a lower surface, a plurality of openings extending between the upper surface and the lower surface, and a recess in the upper surface for receiving an adhesive, wherein a wall of each opening includes a hole fluidly connecting the opening to the recess; wherein the method comprises the following steps: providing a plurality of battery cells; providing a battery cell carrier; inserting each of the plurality of battery cells into a respective one of the openings; delivering adhesive into the recess such that the adhesive passes from the recess through the aperture and into the opening; and curing the adhesive such that the plurality of battery cells are held in the battery cell carrier.

In this way, the adhesive is introduced into the recess and can flow into the opening accommodating the battery cells to hold the plurality of battery cells in the battery cell carrier. The use of recesses in fluid communication with the plurality of openings may allow a single adhesive injection device to be used to secure the plurality of cells within the battery cell carrier. This may provide a fast and efficient method of manufacturing a battery module comprising such a battery cell carrier. Further, since the adhesive may contact the walls of the battery cells held within the battery cell carrier, less adhesive may be used to achieve similar cohesion as compared to battery cell carriers in which the adhesive is used on an outer surface or in which the adhesive is not used within the openings.

The wall of each opening may include an annular ridge, and each annular ridge may prevent adhesive from flowing beyond the lower surface of the cell carrier.

In this way, the amount of adhesive used to secure the battery cells in the battery cell carrier may be reduced because the adhesive does not flow beyond the lower surface of the battery cell carrier. This can reduce weight and cost, and can easily manufacture the battery cell module.

Each of the plurality of battery cells may include an annular groove, and the adhesive may flow into the annular groove. The annular groove may be located at or below the level of the recess. This may result in increased adhesive flow rate and/or improved adhesion due to the additional surface area provided by the annular groove.

In this way, the cured adhesive may interlock with the battery cell, providing a more secure fastening arrangement. This may further allow for the use of less adhesive, for example by providing annular ridges as described above, as the effective surface area of the cell contacted by the adhesive is increased. Other features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, given by way of example only, which refers to the accompanying drawings.

Drawings

For easier understanding of the present invention, embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a schematic illustration of an assembled battery according to one example;

fig. 2 is a schematic view of an arrangement of battery modules in the battery pack of fig. 1;

fig. 3 is a schematic view of a battery module of the battery pack of fig. 1;

Fig. 4A is a first schematic view of a battery cell within the battery module of fig. 3;

FIG. 4B is a second schematic view of the battery cell of FIG. 4A;

FIG. 5A is a schematic top view of a portion of the battery module of FIG. 3 showing battery cells and bus bars;

Fig. 5B is a schematic perspective view of the battery module of fig. 5A;

fig. 6A is an illustrative perspective view of an alternative example of a current collector;

fig. 6B is an explanatory perspective view of a second alternative example of the current collector;

fig. 7A is a schematic perspective view of the battery module of fig. 3;

fig. 7B is a schematic top view of the battery module of fig. 7A;

fig. 8 is a schematic view of the direction of current flow in the arrangement of the battery modules of fig. 2;

fig. 9A is a schematic perspective view of a portion of a battery module including a battery cell carrier according to one example;

FIG. 9B is an end view of the cell carrier and bus bar of FIG. 9A;

fig. 10A is a side view schematic of a battery cell used in the battery module of fig. 9A;

FIG. 10B is a schematic top view of the battery cell of FIG. 10A;

FIG. 11 is a schematic perspective view of a battery cell carrier according to one example;

FIG. 12A is a schematic top view of a battery cell carrier holding a plurality of battery cells according to one example;

Fig. 12B is a schematic perspective view of a portion of the battery cell carrier and the battery cell according to fig. 12A;

FIG. 13 is a schematic view of an alternative simplified battery cell carrier according to one example;

fig. 14 is a schematic view of a battery module according to one example, the battery module including a battery cell carrier according to fig. 13 and a plurality of unit cells;

FIG. 15 is a flowchart of a method of assembling a battery module including a battery cell carrier and a plurality of battery cells according to one example;

FIG. 16 is a schematic side view of an electric vehicle according to one example; and

Fig. 17 is a schematic top view of an underside of an electric vehicle according to one example.

Detailed Description

Details of methods and systems according to examples will become apparent from the following description with reference to the accompanying drawings. In this specification, for purposes of explanation, numerous specific details of certain examples are set forth. Reference in the specification to "an example" or similar language means that a particular feature, structure, or characteristic described in connection with the example is included in at least one example, but not necessarily in other examples. It should also be noted that certain examples are schematically depicted, omitted, and/or simplified as necessary to facilitate explanation and understanding of the concepts behind the examples.

Certain examples described herein relate to a battery module including a plurality of battery cells. The battery module may be part of a battery module arrangement that forms at least a portion of the battery pack. The following description of the battery module and the battery pack is given with reference to the use of these elements in an electric vehicle. However, it should be understood that the elements described herein may be used in any kind of industrial, commercial or domestic application, for example for energy storage and transportation, for example in smart grids, home energy storage, grid load balancing, etc.

Certain examples described herein relate to components of a battery module that includes a cell carrier for securing and positioning a plurality of cells and corresponding bus bars. The cell carriers described herein may allow for accurate and efficient positioning of the bus bars relative to the respective cells during assembly of the associated battery modules. In other examples, current collectors are provided to conduct current along the smaller dimensions of the battery cell stacks included in the battery modules to provide an efficient and reliable connection between adjacent battery modules. For a given cross-sectional area, the smaller size of conducting current along the group of cells may also allow for the use of thinner bus bars to connect the sub-groups of cells, which reduces weight and manufacturing costs. The shorter current path may also reduce the resistance in the bus bar, thereby improving efficiency. Having thinner bus bars may also provide increased flexibility and thus may lead to higher reliability in manufacturing, e.g. connection by laser welding. Other examples described herein provide methods of constructing a battery module including a plurality of battery cells, a battery cell carrier, and/or a bus bar.

Fig. 1 shows a battery pack 100 including an arrangement of battery modules 110a to 110 h. The battery pack 100 is suitable for use in an electric vehicle such as an electric automobile. In electric vehicles, the battery pack may provide electrical energy to power one or more motors and may also provide at least some structural integrity to the vehicle. In this case, as will be described, it is desirable to have a secure and reliable connection between the battery modules 110a to 110h, so that the respective battery packs are resilient to stress, and can maintain secure operation and electrical connection with the motor in the electric vehicle during use.

As shown in fig. 1, the battery modules 110a to 110h are fixed to a frame 120. The frame 120 holds the battery modules 110a to 110h in place in the arrangement. The battery modules 110a to 110h may also be held in this arrangement by fasteners between adjacent battery modules, for example by using bolts or snap rings. Fig. 2 shows a similar arrangement of battery modules without the frame 120.

The battery pack 100 has a first dimension 130 and a second dimension 140 perpendicular to the first dimension. The first dimension 130 is greater than the second dimension 140. The first dimension 130 is parallel to the length of the electric vehicle including the battery pack 100 and the second dimension is parallel to the width of the electric vehicle. As will be described, the battery modules 110a to 110h are arranged and connected such that the total current flows in a direction parallel to the first dimension 130. The total current is made to flow parallel to the first dimension 130, the larger dimension allowing voltages to be added between the battery cell stacks along the major dimension of the battery stack 100 to provide power that can be used to drive the electric motor.

Referring to fig. 2, each battery module, for example, battery module 110a, includes a plurality of battery cells arranged in a unit battery pack. The terms "battery cell" and "unit cell" are used interchangeably herein. The battery module 110a shown in fig. 2 has four unit cell stacks 220a to 220d. However, the battery module may generally have more or less unit cell groups than those shown in fig. 1 and 2. The actual battery cell is not shown in fig. 1 or 2, but is shown in the following fig. 4A to 8. The battery cells in each of the cell stacks 220 a-220 d are electrically connected within their respective cell stacks in a combination of series and parallel connections, for example using bus bars or other suitable electrical connection mechanisms, as will be described. More specifically, in the arrangement 200 of battery modules, each battery module 110a to 110h is electrically connected to an adjacent battery module 110a to 110h. In some examples, each cell stack is electrically connected to at least one other cell stack that is directly adjacent to a cell stack on a directly adjacent battery module. For example, the unit cell stack 220a is electrically connected to the unit cell stack 220e, and so on.

The arrangement 200 of battery modules shown in fig. 2 includes eight battery modules. However, it should be understood that arrangement 200 may include any suitable number of battery modules. The exact number of battery modules in arrangement 200 may depend on the intended use of battery pack 100 and the desired voltages and sizes (and capacities) of the cells and battery modules.

Fig. 3 shows a view of a single battery module, such as battery module 110a of fig. 1 and 2, including a plurality of unit cell stacks 220a to 220d. The battery module 110a includes a support 320 having opposite first (upper) and second (lower) faces 320a, 320b on which the unit cell stacks 220a/220b and 220c/220d are mounted, respectively.

In the illustrative example of fig. 3, the support 320 is a cooling member that includes inlet and outlet ports 330a, 330b, the inlet and outlet ports 330a, 330b being fluidly coupled to respective auxiliary inlet and outlet conduits 340a, 340b. The cooling member has an inner conduit (not shown) through which a cooling fluid may cool the cooling member. The inlet port 330a and the outlet port 330b are conveniently located in channels on the upper face 320a of the cooling member between the unit cell stacks 220a and 220 b. Corresponding channels are shown between the unit cell stacks 220c and 220d on the opposite lower face 320b of the cooling member. In addition to providing convenient locations for the inlet and outlet ports 330a, 330b, the or each channel may be used for a variety of functions, including mounting the battery module 110a within the battery pack 100, and routing cables and other components connected to the battery module 110 a. In the case where the battery module 110a is used in an electric vehicle, the or each channel may be used for wiring of components that may be used to operate the electric vehicle that includes the battery module 110 a.

Although referred to herein as a cooling member, those skilled in the art will appreciate that the support may also be used to heat a battery cell, for example, by heating coolant flowing through the cooling member in use. This may be particularly useful, for example, when it is desired to precondition the battery cells, such as in the case of charging. Thus, the support 320 may be more generally considered a heat transfer member.

Regardless of whether the support 320 performs the function of a cooling member, the support 320 is composed of a rigid material to carry the unit cell stacks 220a to 220d. The support 320 may be made of any suitable material, for example, a metallic material, such as aluminum, titanium, steel, or other suitable high strength material, such as other carbon alloys or composites. The support 320 in this example is a planar member. In this context, the support 320 may be referred to as "planar" even though the surfaces of the facets are not entirely planar, e.g., as a result of accommodating one or more features that may be raised or recessed relative to other generally planar surfaces of the support. In this example, the support 320 is also shown as a generally regular rectangular plate-like member supporting the cube-shaped unit cell stacks 220a through 220d. The unit cell stacks 220a-220 d may be mounted to the support 320 by any suitable method, including but not limited to using an adhesive, a securing mechanism such as a clasp, clip, bracket, or any other suitable attachment mechanism.

The support 320 may be formed to receive the unit cell stacks 220a to 220d. For example, the support 320 may have at least one recess in which the unit cells or the unit cell groups 220a to 220d may be received and mounted. The cubic unit cell stack as shown provides a desired energy density in the unit cell stack. However, in other examples, the unit cell stack may have other shapes, including regular or irregular polygons. In some examples, the shape of the unit cell stack may depend on a frame into which the battery module is to be assembled, the shape of the frame being affected by, for example, the shape and size of a corresponding vehicle using the corresponding battery stack. The shapes of the unit cell stacks may not be identical for all the unit cell stacks. For example, when the battery modules are held in the arrangement, some of the unit cell groups may be shaped such that they conform to the shape of the adjacent unit cell groups.

According to the present example, taking an individual battery module as an example, the four unit cell stacks 220a to 220d are electrically isolated from each other on the support 320. That is, there is no electrical connection between the unit cell stacks 220a to 220d in the battery module 110 a. An electrical insulation may be provided between each of the unit cell groups 220a to 220d and the support 320 to electrically isolate the unit cell groups 220a to 220d. In other embodiments, the support 320 itself may be non-conductive, and thus may naturally provide electrical isolation between the unit cell stacks 220a to 220d on the opposite sides and between the unit cell stacks mounted on the common side.

Each of the unit cell groups 220a to 220d includes a positive terminal connection and a negative terminal connection. In fig. 3, positive terminal connections 350a, 350b, 350d of the respective unit cell stacks 220a, 220b, and 220d can be seen. The negative terminal connections 360a, 360c, 360b of the respective cell stacks 220a, 220c, 220b can be seen. Positive terminal connections 350 a-350 d and negative terminal connections 360 a-360 d may be connected to respective negative and positive terminal connections of adjacent battery modules. In the present disclosure, unless the context dictates otherwise, references to positive and negative terminals may be reversed such that the current may be reversed from that described. In any event, the terminal connections of adjacent battery modules are physically engaged and secured by suitable means, such as bolts and/or any other suitable attachment mechanism. In this example, the positive and negative terminal connections 350 a-360 d each include a protrusion extending parallel to the plane of the support 320 to provide a convenient connection point for the respective unit cell stacks 220 a-220 d.

Fig. 4A shows a simplified schematic diagram of an arrangement of battery cells 420 within a battery pack (e.g., cell stack 220 a) according to one example. The unit cell stack 220a includes a two-dimensional array of battery cells 400. Array 400 has a major dimension in a direction parallel to the x-axis in fig. 4A and a minor dimension in a direction parallel to the y-axis in fig. 4A. The minor dimension is perpendicular to the major dimension and shorter than the major dimension. The array 400 includes a plurality of sub-groups 410a to 410d of battery cells 420, each sub-group 410a to 410d in the array 400 including a plurality of parallel-connected battery cells arranged in a linear arrangement and spanning a major dimension. In fig. 4A, four subgroups 410 a-410 d are shown, although other numbers of subgroups, e.g., six or more, may be employed. In fig. 4A, alternating white and shading is used to distinguish subgroups 410 a-410 d from adjacent subgroups 410 a-410 d. The number of unit cells in each of the sub-groups 410a to 410d may be the same or different in all of the sub-groups 410a to 410 d. In some examples, the first set of sub-groups of cells may include a first number of cells and the second set of sub-groups of cells may include a second number of cells, wherein the first number of cells is different from the second number of cells.

The sub-groups 410a to 410d are electrically connected in series with each other and are arranged such that the total current flows through the unit cell group 220a in a direction parallel to the minor dimension. In other words, the battery cells 420 in the sub-groups 410a to 410d are connected in parallel with other battery cells 420 in the corresponding sub-groups 410a to 410d, and the sub-groups 410a to 410d are connected in series with the adjacent sub-groups 410a to 410 d. Flowing the total current in a direction parallel to the minor dimension of the unit cell stack 220a in the battery module 110a distributes the current over the length of the battery module.

Fig. 4B shows a perspective view of the unit cell stack 220a of fig. 4A, in which like reference numerals are used

Corresponding to the same features. Secondary dimension y of the array of battery cells 400 in cell stack 220a

Shorter than the major dimension x of the array of battery cells 400 in the unit cell stack 410. The major dimension x of the array 400 is two to four times greater than the minor dimension y of the array 400. For example, the major dimension x may be three times greater than the minor dimension y. The battery cells 420 shown in fig. 4A and 4B are cylindrical, however, the battery cells 420 in the battery module may be other suitable shapes. In some examples, the battery cells 420 are elongated and may have any suitable cross-section along the length.

Fig. 5A shows a top view of the unit cell stack 220a mounted on the support 320, which is a part of the battery module 110 a. The unit cell stack 220a is composed of sub-stacks 410a to 410 d. In this view, the arrangement further includes a plurality of bus bars 500 a-500 c and current collectors 510a and 510b. The number of bus bars will depend on the number of sub-groups 410a to 410d of unit cells, and in some examples, a battery module may include only one bus bar. Each of the bus bars 500a to 500c includes a plurality of positive connection points (not shown), each of which is connected to a corresponding positive terminal of the unit cells 420 in the first lower-layer sub-group, thereby connecting the unit cells of the sub-group in parallel. Each of the bus bars 500a to 500c further includes a plurality of negative connection points (not shown), each of which is connected to a corresponding negative terminal of the unit cells 420 in the second lower-layer sub-group adjacent to the first sub-group, thereby connecting the unit cells of the sub-group in parallel. In this way, each bus bar connects the positive terminal of the first subgroup to the negative terminal of the second subgroup, such that the subgroups are connected in series with each other, and such that the total current flows in the respective battery modules parallel to the short axis of the unit cell group. Using bus bars to connect adjacent sub-groups of unit cells in this manner provides a convenient and reliable way of electrically connecting adjacent sub-groups of unit cells.

Current collectors 510a and 510b are used to collect current from respective sub-groups 410a and 410d of unit cells located at the periphery of unit cell stack 220 a. Each current collector 510a or 510b includes an electrical conductor having an edge, acts as a bus bar, spans the major dimension of the respective cell stack 220a, and includes a plurality of connection points (not shown), each of which is connected to a respective positive or negative terminal of a cell 420 in the respective lower sub-stack 410a or 410d, thereby connecting the cells of the sub-stack 410a or 410d in parallel. Referring also to fig. 5B, the battery module 110a includes first and second unit cell stacks 220a, 220c disposed on opposite sides of the support 320. The first and second current collectors 510a, 510c are provided for collecting current from a subset of the unit cells on the periphery of the respective first and second unit cell groups 220a, 220c. The current collectors 510a, 510c each include converging regions 530a and 530c that converge to relatively narrow electrical contacts 520a and 520c. In the example shown, electrical contacts 520a and 520c each include protrusions from the respective current collectors 510a and 510c to provide simple connection points through which electrical contacts of adjacent cell stacks may be juxtaposed and attached. These protrusions may be connected to the further protrusions by using any suitable attachment mechanism. For example, bolts may be positioned through holes (not shown) in the protrusions, and then may be fixed to additional protrusions of the adjacent unit cell stack. The protrusion protrudes in a direction parallel to the minor dimension. In this way, during assembly, the electrical contacts 520a extend toward the adjacent unit cell stack, and thus can be easily attached.

Each electrical contact 520a, 520b (one positive terminal and the other negative terminal) of the respective cell stack 220a is used to electrically couple the respective cell stack 220a to another cell stack or to the output of the battery module 110a or stack that includes the cell stack 220 a. In some examples, convergence region 530a may converge to more than one electrical contact, for example to two or even three relatively narrow electrical contacts. Fig. 6A shows a first alternative example of a current collector 600, including a convergence region 610 converging to three electrical contacts 620a, 620b, 620 c. A second alternative current collector 630 is shown in fig. 6B, comprising three converging regions 640, 650, 660, each having a respective electrical contact 670a, 670B, 670c. Such an arrangement may provide redundancy in the event of failure of one of the electrical contacts 670a, 670b, 670c, while still enabling the electrical contact to extend only across a portion of the length of the current collector 630. Current collectors such as described with reference to fig. 5A, 5B, 6A and 6B provide a reliable and safe way to electrically connect adjacent cell stacks of different battery modules to allow current to flow therebetween. As shown in fig. 5A and 5B, converging the current collectors 510a to a single electrical contact 520a simplifies assembly of the battery module 110a, and thus, production efficiency may be improved. In addition, a single electrical contact 520a may increase the reliability of the connection between battery modules and reduce the number of potential points of failure. In the illustrative example of fig. 5A and 5B, current collectors 510a and 510B on opposite peripheries of unit cell stack 220a allow respective battery modules 110a to be electrically coupled to two battery modules, one on each side thereof. By connecting the unit cells 420 in this manner, the thickness of the current collectors 510a and 510b can be reduced. Accordingly, the current collectors 510a and 510b including the protrusions may be at least partially flexible, thereby allowing for simpler manufacturing of the battery module 110a while increasing elasticity to torsional stress. This may be beneficial when used in an electric vehicle where such stresses may occur during vehicle operation due to factors such as uneven road conditions, high speeds, cornering and other factors that may cause the vehicle components to bend. In this example, current collectors 510a and 510b are formed from a sheet of flexible and formable material, such as copper.

Returning to fig. 5B, each of the current collectors 510a, 510B, and 510c extends in a direction orthogonal to the primary and secondary dimensions of the unit cell stack. The orthogonal direction extends downward from the upper surface of each unit cell group 220a or upward from the lower surface of each unit cell group 220 c. This may allow current collectors 510a, 510b, and 510c to have electrical connection points at locations that are easily connected to other battery modules having similar and complementary connection points. The current collector 510a extends toward the support 320 in directions orthogonal to the major dimension x and the minor dimension y, respectively. This allows the electrical contacts 520a to be positioned near the center plane of the battery module defined by the support 320. This protects the electrical contact 520a of the current collector 510a when assembled and positions the electrical contact 520a in close proximity to the electrical contact 520c of the current collector 510c attached to the unit cell stack 220c located on the underside of the support 320. This symmetrical arrangement simplifies the assembly process, in particular the connections and/or cabling that can be made between the modules, when applied to all battery modules and corresponding cell stacks. In fact, the unit cell stacks (and the corresponding battery modules carrying them) may be interconnected using a combination of bus bars and current collectors, without resorting to, to a large extent, more complex and possibly less reliable electrical connection schemes, including, for example, cables and wiring.

As each current collector 510a and 510b spans the length of the major dimension of the unit cell stack 220a, converging the current collectors 510a and 510b in a direction orthogonal to the major and minor dimensions of the unit cell stack 220a allows the contact points 520a and 520b of the current collectors 510a and 510b to be less than the length of the major dimension while still allowing the current collectors 510a and 510b to pass the total current across the major dimension to the electrical contacts 520a and 520b.

As shown in fig. 5A and 5B, the electrical contacts 520a, 520B, 520C are offset to either side of a central axis C at the center of the array of battery cells 400, which is parallel to the next dimension. The location of offset electrical contacts 520a, 520b, and 520c allows electrical contacts of adjacent cell stacks and cell stacks on opposite sides to be conveniently electrically coupled to each other or electrically isolated from each other as desired. In the example shown, the electrical contact 520a of the first current collector 510a is offset from the central axis C in a first direction parallel to the major dimension (i.e., to the right of the central axis C as shown). The electrical contact 520C of the second current collector 510C is offset from the central axis in a second direction opposite the first direction (i.e., to the left of the central axis C as shown). Having opposing, offset electrical contacts 510a and 520c provides the desired electrical contact with the proper dimensions while maintaining electrical isolation between first cell stack 220a and second cell stack 220 c. This also allows the current collectors 510a, 510b used on both sides of the unit cell stack 220a to have the same form, so that only one type of current collector needs to be manufactured. This increases the scalability of the manufacturing process because fewer types of components can be manufactured to produce a battery module.

Each electrical contact 520a, 520b, 520c may be offset from the support 320 in a direction orthogonal to the plane of the support 320. Alternatively, each electrical contact 520a, 520b, 520c may be substantially coplanar with the support 620. In this way, adjacent battery modules may be attached by their respective coplanar supports while providing a large contact area between adjacent electrical contacts.

In other examples, current collectors 510a, 510b, and 510c do not include electrical contacts 520a, 520b, and 520c extending from respective current collectors 510a, 510b, and 510c, respectively, but include contact points. For example, there may be some other electrical attachment mechanism that may be used to connect adjacent cell stacks. In some examples, the electrical contacts attached to opposing current collectors of a single cell stack may be different types of electrical connectors. For example, the current collector serving as the positive electrode terminal may include a male connector, and the current collector serving as the negative electrode terminal may include a female connector, so that adjacent unit cell groups may be connected by attaching the corresponding negative electrode terminal to the positive electrode terminal of the adjacent unit cell group. This also prevents the positive electrode terminal of the first unit cell group from being accidentally connected to the positive electrode terminal of the second unit cell group.

Fig. 7A and 7B are views similar to those of fig. 5A and 5B, but illustrate a complete battery module 110a including two unit cell stacks on each opposite face of the support 320. This arrangement is similar to that shown in fig. 3, but without the cell housing.

Fig. 8 shows a view representing an arrangement 800 of four rows of battery modules, such as the first four rows of battery modules 110 a-110 d of fig. 1 and 2. Fig. 8 shows in more detail that the supports of the individual battery modules are coplanar, which means that in this case the upper and lower surfaces of the battery modules 110a to 110d are also coplanar. For clarity, connections are omitted from fig. 8, although as described above, the cell stacks are connected such that current flows in a direction parallel to the minor dimension y of each cell stack and along rows of adjacent sub-stacks (represented by arrows P, Q, R and S) parallel to the major dimension 130 of the stack. The connection is such that current flows in one direction P along the rows of the unit cell stacks on the top and left of the support and in the opposite direction Q along the rows of the unit cell stacks below and left of the support. In this manner, the rows of unit cell stacks may be conveniently connected in series at the ends of the battery stack 100 by the connectors 830a, 830 b. In other examples, connectors 830a, 830b may be located at the other end of battery pack 100, as desired. For example, in the illustrated example, the left upper row of the unit cell stack is connected in series with the left lower row of the unit cell stack, and the right upper row of the unit cell stack is connected in series with the right lower row of the unit cell stack. Alternatively, the upper left and right rows of the unit cell stack may be connected in series with each other, and the lower left and right rows of the unit cell stack may be connected in series with each other. In either case, it is convenient that all four rows of unit cell stacks may be connected in series with each other.

Referring now to fig. 9A, 9B, 10A and 10B, fig. 9A shows a perspective view of at least a portion of a battery module 900, the battery module 900 including a battery cell carrier 910, a plurality of battery cells 420, and a bus bar 930 electrically connecting the plurality of battery cells 420. The battery cell carrier 910 includes a plurality of openings, each opening receiving a respective one of the plurality of battery cells 420.

As shown in fig. 10A and 10B, each of the plurality of battery cells 420 includes a first end 1010 and a second end 1020, and a positive terminal 1040 and a negative terminal 1050 are located at the first end 1010. The opening in the battery cell carrier 910 is configured such that the first end 1010 of each of the unit cells 420 received in the opening is at least partially exposed through the battery cell carrier 910. This allows the positive and negative terminals 1040, 1050 of each cell to be connected by a respective bus bar 930. In some examples, only a portion of each of the positive and negative terminals 1040 and 1050 of each of the cells 420 is exposed through the battery cell carrier 910 to prevent excessive corrosion or dust from affecting the cells 420. In other examples, the entire first end of each cell 420 is exposed through the cell carrier 910 such that the bus bar 930 can be easily connected to a terminal, using a securing feature (as will be described) to position the bus bar 930. This allows the bus bar 930 to be easily connected to the associated cell terminals, reducing the risk of poor connection. Having both the positive and negative terminals 1040, 1050 on the first ends 1010 of the unit cells simplifies the construction of the battery module and requires that the bus bars 930 be located on only one side of the corresponding unit cell stack.

The plurality of battery cells 420 in fig. 9A includes first (shown in white) and second (shown in phantom) parallel-connected row groups of battery cells. The bus bar 930 is connected to the positive terminal of the first (white) parallel connection bank of battery cells and the negative terminal of the second (shaded) parallel connection bank of battery cells.

Fig. 9B schematically shows an end view (p, q) of two parallel-connected row groups of the battery cells of fig. 9A. As shown in fig. 9B, the battery cell carrier 910 includes at least one securing feature 940 to position the bus bar 930 relative to the battery cell carrier 910. While only one fixation feature 940 is visible, other examples may instead employ multiple fixation features, such as spanning the major dimension of the cell carrier 910. In this example, the main size is defined as the size of the battery module spanning the maximum number of unit cells.

The use of the fixation feature 940 to position the bus bar 930 relative to the cell carrier 910 ensures that the position of the bus bar 930 relative to the cell is precisely defined. The presence of the securing features 940 also means that the bus bar 930 can be efficiently and accurately positioned for attaching the bus bar 930 to the battery cells 420 during manufacturing. The increased accuracy of the bus bar position due to the presence of the securing features 940 also facilitates, in part, the use of a cell 420 having positive and negative terminals on the same end 1010 of the cell 420. An inaccurate connection always causes a short circuit between the positive and negative terminals 1040 and 1050 of the single unit cell 420.

The securing features 940 may include any suitable attachment mechanism for securing and positioning the bus bar 930 relative to the cell carrier 910. According to an example, the securing features 940 include upstanding protrusions on the outer surface of the battery cell carrier 910. The bus bar 930 includes complementary securing holes 950, as shown in phantom in fig. 9B, to receive the securing features 940 and facilitate alignment between the bus bar 930 and the cell carrier 910. Once assembled, the securing features 940 deform (e.g., using heat and/or pressure) and include deformed portions 960 (having an expanded width relative to the normal width of the securing features) to secure the bus bar 930 and the cell carrier 910 together.

Referring back to fig. 10A and 10B, the battery cell 420 includes an annular recess 1030 around the upper perimeter of the battery cell 420, and the positive and negative terminals 1040, 1050 of the battery cell are coplanar. However, in other examples, one of the positive or negative terminals 1040 or 1050 may be elevated or recessed as compared to the other of the positive or negative terminals, and the bus bars may be configured accordingly. In the example shown, the negative terminal 1050 forms part of the housing of the unit cell 420. In other embodiments, the terminals may be reversed such that the positive terminal forms part of the housing of the unit cell 420. Alternatively, the housing of the unit cell 420 may include an insulating material such that the positive and negative terminals 1040 and 1050 are exposed at the top side of the unit cell 420 only at the first end 1010.

Fig. 11 shows a perspective view of a portion of a battery cell carrier 1100 according to another example, the battery cell carrier 1100 being suitable for use in a unit cell stack of the type shown in any one of fig. 1 to 8. The battery cell carrier 1100 includes a plurality of openings 1140 each for receiving a corresponding one of the plurality of battery cells. The securing features, such as securing features 1110a, 1110b, and 1110c, are included as upstanding protrusions on the upper surface 1120a of the cell carrier 1100. When the battery module is assembled, the upstanding projections engage with the corresponding bus bars, thereby precisely aligning the bus bars with the battery cell carrier and thus with the battery cells 420 and preventing the bus bars from contacting the incorrect terminals of the battery cells 420.

The upstanding projections 1110a, 1110b, 1110c are made of a deformable material and are deformable by the application of heat and/or pressure to secure the respective bus bars to the cell carrier 1100. Once deformed, the upstanding projections 1110a to 1110c secure the bus bar to the cell carrier 1100.

The deformable fixation features 940 may be made of a suitable polymer or metallic material. Alternatively, the securing features 940 may include fasteners or other mechanisms that may be attached to the bus bar. The securing features 940 may be made of a semi-rigid or flexible material and may be shaped such that they provide a secure press fit when engaged with the bus bar. For example, the fixation feature 940 may have a hemispherical end and a cutout below the hemispherical end. Once the hemispherical ends have been pressed into the corresponding securing holes 950 in the bus bar, at least a portion of the underside of the hemispherical ends may engage the surface of the securing holes and prevent the bus bar from being removed.

Returning to fig. 11, the battery cell carrier 1100 is for holding a plurality of battery cells 420 and includes an upper surface 1120a and a lower surface 1120b. The cell carrier 1100 includes a plurality of walls 1130 extending between the upper surface 1120a and the lower surface 1120b. Each of the plurality of walls 1130 at least partially defines an opening 1140 for receiving a corresponding one of the plurality of battery cells 420. Each opening 1140 in the battery cell carrier 1100 is configured to receive a respective battery cell 420 therethrough. Each of the plurality of walls 1130 is adapted to be adjacent to a respective cell wall of a respective battery cell 420 when the battery cell 420 is received in the respective opening. The wall 1130 of each opening includes an annular ridge 1150 that at least partially defines the opening 1140, either adjacent the lower surface 1120b or at the lower surface 1120b. The annular ridge 1150 of each wall 1130 is configured to contact and retain, in use, a battery cell 420 received in a respective opening such that the wall 1130 is spaced from the respective cell wall by an amount at least equal to the width of the annular ridge 1150.

The battery cell carrier 1100 includes a rigid material that may provide support for the battery cells 420 mounted therein. The battery cell carrier 1100 may include a material softer than the surface material of the battery cells 420 such that the risk of damaging the battery cells 420 by the battery cell carrier 1100 during manufacture and use is reduced. For example, the cell carrier 1100 may be made of hardened plastic or any other suitable material. In some examples, the battery cell carrier 1100 is at least partially flexible and/or resilient such that when the battery cells 420 are inserted into a respective one of the openings, the respective annular ridge 1150 engages the battery cells 420 and deforms according to the battery cells 420. The annular ridge 1150 is sufficiently rigid that it continues to engage the cell 420 and at least partially holds the cell 420 in place, such as by friction.

The annular ridge 1150 provides a firm fit between the unit cells 420 and the battery cell carrier 1100 received in the corresponding one of the openings 1140, thereby preventing the unit cells 420 from sliding and increasing stability. According to the present example, the annular ridge 1150 surrounds the corresponding opening 1140 and engages the entire periphery of the unit cell 420.

In some examples, the battery cells 420 may be secured within the battery cell carrier 1100 by using a suitable adhesive. The adhesive contained in the opening 1140 contacts the cell walls of the respective battery cells and holds the battery cells in the battery cell carrier 1100. In this case, the annular ridge 1150 conveniently prevents adhesive from leaking down the respective cell 420, below the lower surface 1120b of the cell carrier 1100, and toward the second end of the cell 420.

The cell carrier 1100 includes a recess 1160 in its upper surface 1120a for receiving an adhesive. In the example shown, the cell carrier 1100 is planar and the lower surface 1120b is substantially planar.

The wall 1130 includes an aperture, such as aperture 1170, between the respective opening 1140 and the recess 1160. Each aperture 1170 fluidly connects a respective one of the openings 1140 to the recess 1160 such that during adhesive insertion, adhesive flows from the recess 1160, through the apertures 1170 and into the openings 1140. The hole 1170 has a boundary extending downward from the upper surface 1120 a. The adhesive flowing into the openings 1140 flows around the cavity or region between the wall 1130 and the cell walls of the battery cells 420 received in the corresponding openings 1140. The adhesive fills this region from the lower boundary defined by the annular ridge 1150 and penetrates into the annular recess 1030 of the cell 420. The recess 1160 may be said to be in fluid communication, in use, with the cell walls of the battery cells 420 received in each respective opening. In the example shown in fig. 11, the recesses 1160 are configured such that during adhesive introduction, adhesive may flow through three apertures, including aperture 1170, and onto the walls of three respective cells 420, which are received in their respective openings in a hexagonal close-packed arrangement. However, it should be understood that in other examples, there may be only one hole per recess. Where a single recess is configured to allow adhesive to flow through multiple holes, the adhesive application process may be simplified because fewer separate injection nozzles may be used to inject adhesive into the cell carrier 1100. This may increase the speed and efficiency of manufacturing. Having recesses 1160 and holes 1170 arranged in this manner, and given a sufficiently free flowing adhesive, allows gravity to introduce the adhesive and secure the unit cells 420 in a fixed arrangement without requiring a more complex pressure injection process.

In this embodiment, the annular grooves 1030 of the battery cells 420 are positioned such that they are at or below the level of the recesses 1160. This may result in increased adhesive flow rate and/or improved adhesion due to the additional surface area provided by the annular recess 1030.

The formation of the cavity or region between the wall 1130 and the cell walls of the cells 420 provides a relatively large surface area for the cells 420 and the cell carrier 1100 for the adhesive to contact the cells 420 within the cell carrier 1100 and thereby firmly secure the cells 420 within the cell carrier 1100. The ridges 1150, which are arranged to contain adhesive within the cavities, ensure that the adhesive is not wasted by leakage and that the cells 420 are not covered by excess adhesive (which may affect thermal control and/or efficiency of the cells 420), thereby reducing cost and weight.

As noted, the adhesive is in the form of a fluid prior to solidification so that an appropriate applicator may be used to introduce the adhesive into the recess 1160. Thus, the adhesive flows under the force of gravity. Once applied, the adhesive begins to set and after a period of time, the adhesive forms a solid that secures and/or secures the portions of the cell carrier and cell 420 that are in contact with the adhesive. The adhesive may have other characteristics, such as thermal conductivity, or may provide thermal insulation. In some examples, when cured, an adhesive may be disposed within the opening 1140 and in the corresponding hole 1170 and/or recess 1160.

In some examples, a bus bar (not shown) that may be fixed to the aforementioned unit cell carrier 1100 may include at least one adhesive insertion hole. The or each adhesive insertion aperture is aligned with a respective recess 1160, for example by the arrangement of the securing features 1110 a-1110 c. This arrangement allows an adhesive to be introduced into the recess to secure the cells 420 in the cell carrier 1100 once the bus bars are positioned with the respective cells 420 and/or electrically connected to the respective cells 420. The battery cell carrier 1100 may additionally include at least one mounting feature (not shown) for battery management system circuitry. The battery management system circuitry may be located with its associated battery module and may monitor and/or control one or more parameters of the battery module including, for example, temperature, charge capacity, output current and/or voltage or remaining charge. The battery management circuitry may include any number of sensors including, but not limited to, thermometers, voltmeters, ammeter, ohmmeters, accelerometers, and any other suitable sensors. The battery management circuitry may also include at least one controller comprising any suitable combination of hardware and software for controlling one or more parameters of the battery module.

Fig. 12A shows a top view of an example battery cell carrier 1100 that holds or secures a plurality of battery cells 420 in their respective openings. In some embodiments, at least one opening 1200 in the battery cell carrier 1100 is a virtual opening configured to block insertion of the battery cells 420 therethrough. The virtual opening 1200 is located adjacent to and in fluid communication with the recess. The virtual openings may be used to maintain consistent adhesive fluid characteristics during adhesive injection. The consistency and behaviour of the adhesive fluid can be tightly controlled, so that the flow dynamics of the adhesive can be negatively affected in the areas where the recesses connect to fewer holes and thus are in fluid communication with fewer cell walls. Thus, the virtual openings 1200 can be used to maintain adhesive flow characteristics in these areas.

Fig. 12B shows a perspective view of the battery cell carrier 1100 and the plurality of unit cells 420 shown in fig. 12A. Fig. 12B illustrates a fixation feature, such as fixation feature 1110a. Additional securing features 1210 are shown on the perimeter of the cell carrier and are used to position the current collectors relative to the corresponding sub-groups of cells 420.

Fig. 13 shows a simplified schematic diagram of an alternative cell carrier 1300 according to one example. In this example, the cell carrier 1300 does not include a securing feature for positioning the bus bar, and the recess 1310 is in fluid communication with both openings 1320, 1330 only via respective holes 1340, 1350 in a wall (e.g., wall 1360). Similar to that shown in fig. 11, the cell carrier 1300 includes an upper surface 1370 and a lower surface 1380, wherein the recess 1310 is in the upper surface.

Fig. 14 shows the battery cell carrier of fig. 13 having a plurality of battery cells 420, such as battery cells 420 received in respective openings 1320. The annular groove (not shown in this figure) of the battery cell 420 is configured to hold an adhesive inserted through the corresponding hole 1340, 1350 in the wall 1360. When the battery cell 420 is inserted into the opening 1320 of the battery cell carrier 1300, the annular groove may be positioned above the annular ridge 1390 in the wall 1360 toward the aperture 1340. In this way, the adhesive may fill the annular recess 1030, which provides a greater surface area on the surface of the unit cell 420 to bond therewith. Furthermore, in this and other examples, the annular recess 1030 provides greater flexibility to the load exerted on the cell 420 or the cell carrier 1300.

Fig. 15 illustrates a flow chart of a method 1500 of assembling a battery module including a battery cell carrier and a plurality of battery cells 420 according to one example. The battery cell carrier is a battery cell carrier according to examples described herein. At block 1510, the method 1500 includes providing a plurality of battery cells 420. At block 1520, the method 1500 includes providing a battery cell carrier.

At block 1530, the method 1500 includes inserting each of the plurality of battery cells 420 into a respective one of the openings for receiving the battery cells 420. At block 1540, the method 1500 includes introducing adhesive into the recess such that the adhesive flows out of the recess, through the aperture, and into the opening, and such that upon solidification, the adhesive retains the plurality of cells 420 in the cell carrier.

Any of the example battery modules described herein may be a battery module for an electric vehicle.

In one example, a battery pack is provided that includes a plurality of battery modules according to any of the examples described herein. The battery pack may be a battery pack for an electric vehicle including a frame. The battery pack may form part of the shape and/or structure of the electric vehicle. In one example, an electric vehicle is provided. For example, fig. 16 shows a schematic side view of an electric vehicle 1600 that includes a battery pack 1610 disposed in the electric vehicle 1610. For example, battery pack 1610 is disposed toward the underside of electric vehicle 1600 in order to lower the center of mass of electric vehicle 1600. Fig. 17 shows a schematic top view of an electric vehicle 1700 according to one example. The electric vehicle 1700 includes a front electric drive unit battery 1710 and a rear electric drive unit battery 1720 for delivering power to at least one drive wheel 1730 of the electric vehicle 1720. The vehicle 1700 includes a battery pack 1740, with the battery pack 1740 being located between the front and rear electric drive unit cells 1710, 1720. In this example, the front and rear electric drive unit cells 1710, 1720 include an inverter for converting DC battery current to AC current for delivery to the traction motor. In the illustrated embodiment, the battery pack 1740 includes electrical connections 1750 for connecting the battery pack to the rear electric drive unit cell 1720. The battery pack 1740 may also have an electrical connection with the front drive unit battery 1730. In some examples, the battery pack 1740 is arranged such that the battery input/output 1760 is positioned toward the front electric drive unit cell 1710 of the electric vehicle 1700, and the electrical connection 1750 extends from the battery input/output 1760 along the channel to the rear electric drive unit cell 1720. The electrical connector 1750 is connected to an inverter of the rear electrical drive unit cell 1720. In other examples, electrical connections connecting the input/output 1760 of the battery pack 1740 to the front electric drive unit cell 1710 or the charging port of the electric vehicle 1700 may extend along the path of the battery pack 1740. In other examples, battery input/output 1760 may be located anywhere else on battery pack 1740, such as toward rear electric drive unit battery 1720 of electric vehicle 1700 in which it is used.

The above embodiments should be understood as illustrative examples of the present invention. Further embodiments of the invention are envisaged. It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.

Claims

1. A battery cell carrier for holding a plurality of battery cells, the battery cell carrier comprising an upper surface and a lower surface,

A plurality of openings extending between the upper surface and the lower surface, each opening for receiving one of the plurality of battery cells; and

A recess in the upper surface for receiving adhesive,

Wherein the wall of each opening includes a hole fluidly connecting the opening to the recess such that adhesive inserted into the recess flows from the recess through the hole into the opening,

And wherein each opening comprises an annular ridge surrounding a respective one of the openings.

2. The battery cell carrier of claim 1, wherein each aperture extends upwardly to an upper surface.

3. The battery cell carrier of claim 1 or 2, wherein the battery cell carrier is planar and the lower surface is planar.

4. A cell carrier according to any preceding claim, wherein each ridge is located between the aperture and the lower surface.

5. The battery cell carrier of any preceding claim, wherein the ridge contacts a battery cell received in the opening.

6. The battery cell carrier of claim 5, wherein each ridge is arranged to retain an adhesive within the opening.

7. The battery cell carrier of any one of the preceding claims, wherein at least one of the openings is a virtual opening configured to block insertion of a battery cell therethrough, the virtual opening being located adjacent to and in fluid communication with the recess.

8. A battery cell carrier according to any preceding claim, wherein the battery cell carrier comprises at least one mounting feature for mounting circuitry of a battery management system to the battery cell carrier.

9. A battery cell carrier according to any preceding claim, wherein the battery cell carrier comprises at least one first securing feature for engagement with at least one second securing feature of a busbar to align the busbar relative to the battery cell carrier.

10. The battery cell carrier of claim 9, wherein the at least one first securing feature comprises an upstanding protrusion, and wherein the at least one second securing feature comprises a securing aperture for engagement with the at least one upstanding protrusion.

11. The battery cell carrier of claim 10, wherein the upstanding protrusion is deformable to secure the bus bar to the battery cell carrier.

12. A battery cell carrier according to any preceding claim, comprising a plurality of recesses for receiving adhesive, each recess being in fluid connection with a plurality of openings through a respective aperture.

13. A battery module comprising a plurality of battery cells, a battery cell carrier holding the plurality of battery cells, and an adhesive, the battery cell carrier comprising:

an upper surface and a lower surface; a plurality of openings extending between the upper and lower surfaces, each opening receiving one of the plurality of battery cells, each opening including an annular ridge surrounding a respective one of the openings; and

A recess in the upper surface for receiving an adhesive;

wherein the wall of each opening includes a hole fluidly connecting the opening to the recess such that adhesive extends from the recess through the hole into the opening, and

The adhesive is in contact with the respective battery cell such that the battery cell is held in the battery cell carrier by the adhesive.

14. The battery module of claim 13, wherein the battery module comprises a bus bar, the cell carrier comprises at least one first securing feature, and the bus bar comprises at least one second securing feature, wherein the at least one first securing feature engages with the at least one second securing feature to align the bus bar relative to the cell carrier.

15. The battery module of claim 14, wherein the at least one first securing feature comprises an upstanding protrusion, and wherein the at least one second securing feature comprises a securing aperture that engages the at least one upstanding protrusion.

16. The battery module of claim 15, wherein the at least one first securing feature has a deformed portion to secure the bus bar to the cell carrier.

17. The battery module of any of claims 13-16, wherein each annular groove is configured such that the annular groove retains adhesive inserted through the aperture.

18. The battery module of any of claims 13 to 17, wherein, for each opening accommodating a battery cell, the respective wall of the opening and the respective cell wall define an annular cavity for accommodating an adhesive between the battery cell and the battery cell carrier.

19. The battery module according to any one of claims 13 to 18, wherein the battery module is used for an electric vehicle.

20. An electric vehicle comprising the battery module according to any one of claims 13 to 19.

21. A method of assembling a battery module comprising a battery cell carrier and a plurality of battery cells, the battery cell carrier comprising:

An upper surface and a lower surface; a plurality of openings extending between the upper and lower surfaces, each opening including an annular ridge surrounding a respective one of the openings;

A recess in the upper surface for receiving adhesive, wherein the wall of each opening includes a hole fluidly connecting the opening to the recess,

Wherein the method comprises:

providing a plurality of battery cells;

Providing a battery cell carrier;

inserting each of the plurality of battery cells into a respective one of the openings;

delivering adhesive into the recess such that the adhesive flows from the recess through the aperture and into the opening; and

The adhesive is cured such that the plurality of battery cells are retained in the battery cell carrier.

22. The method of claim 21, wherein the annular ridge prevents the adhesive from flowing beyond a lower surface of the cell carrier.

23. The method of claim 21 or 22, wherein each of the plurality of battery cells comprises an annular groove, and the adhesive flows into the annular groove.