CN114788081A

CN114788081A - Battery cell carrier, battery module and method of assembling the same

Info

Publication number: CN114788081A
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: 2022-07-22
Also published as: GB201915080D0; GB2588390A; WO2021074574A1; GB2588390B

Abstract

A battery cell carrier (1100) for holding a plurality of battery cells (420) has an upper surface (1120a) and a lower surface (1120 b). The battery cell carrier (1100) has a plurality of openings (1140) extending between an upper surface (1120a) and a lower surface (1120 b). The cell carrier (1100) has a recess (1160) in an upper surface (1120a) 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 assembling method thereof

Technical Field

The present invention relates to batteries, and particularly, but not exclusively, to a battery module and a battery pack including the same, and a battery cell carrier. 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

Batteries are an indispensable part of electric vehicles. 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 battery packs in electric vehicles, particularly electric vehicles, 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 electric vehicles that is easy to manufacture and maintain. Reducing the weight of the battery pack may also be a desire to improve performance in the field of electric vehicles.

Disclosure of Invention

According to a first aspect of the present invention, there is provided 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 a 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.

In this manner, when the battery cell is positioned 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 the 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 may improve the speed and efficiency of manufacturing a battery module including such a battery cell carrier. In addition, because the adhesive is in contact with the cell walls within the cell carrier, less adhesive can be used to achieve similar cohesion when compared to using an adhesive on the outer surface or a cell carrier that does not use adhesive within the recess.

Each hole may extend up 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 clogging or blocking. It is also possible to achieve a greater flow rate of the adhesive, thereby reducing the time for manufacturing a battery module including such a battery cell carrier.

The 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, other than the openings.

Having recesses only on the upper surface may prevent the adhesive from spilling out of the cell carrier. Furthermore, the absence of a recess in the lower surface may preserve the structural integrity of the battery cell carrier such that it may provide sufficient support and structure to hold the battery cells and, in some examples, the respective 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 include an annular ridge, e.g., 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 an annular ridge around the respective opening may prevent adhesive from flowing down the sides of the battery cells that may be housed 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 cell carrier.

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

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

The ridges may be arranged to contact battery cells receivable in the respective openings.

In this manner, the annular ridge may be configured to secure a battery cell that may be received within its respective opening.

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

In this way, adhesive is not wasted by leakage, and the battery cell is not covered with excessive adhesive, which may reduce cost and weight. In addition, excessive binder may affect the thermal control of the battery cell.

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 manner, 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 impede insertion of a battery cell therethrough, the virtual opening being adjacent to and in fluid communication with the recess.

The virtual opening may be used to maintain consistent adhesive flow characteristics for openings adjacent the virtual opening 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 the corresponding battery management system circuit to be collocated with the corresponding cell stack for monitoring and controlling parameters of the cell stack.

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 bars 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 protrusion and the at least one second securing feature may comprise a securing aperture for engagement with the at least one upstanding protrusion.

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

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

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

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

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

According to a second aspect of the present invention, there is provided 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 surface and the lower surface, each opening receiving one of the plurality of battery cells; and a recess in the upper surface for receiving adhesive; wherein a 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 battery cell such that the battery cell is retained in the battery cell carrier by the adhesive.

In this manner, 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 that are in fluid communication with the plurality of openings through the apertures may allow a single adhesive injection device to be used to secure a plurality of battery cells within the battery cell carrier. This may improve the speed and efficiency of manufacturing a battery module including such a battery cell carrier. In addition, because the adhesive is able to enter the openings and contact the surfaces of the individual cells within the openings, less adhesive can be used to achieve similar cohesion as compared to battery cell carriers where the adhesive is used on the outer surface or not in the openings.

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 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 protrusion and the at least one second securing feature may comprise a securing aperture that engages the at least one upstanding protrusion.

Having corresponding securing holes and securing 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 wall of each cell may include an annular groove that retains 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 an increase in 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 inserted excessively, thereby allowing the adhesive to be used more effectively and allowing the battery cells to be fixed using a reduced amount of adhesive, which may otherwise affect the weight and cost of the battery module and the battery pack.

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

The battery module may be used for 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 comprising a plurality of battery cells and a battery cell carrier comprising: 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 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 corresponding one of the openings; delivering adhesive into the recess such that adhesive flows from the recess through the aperture and into the opening; and curing the adhesive such that the plurality of battery cells are retained in the battery cell carrier.

In this manner, adhesive is introduced into the recess and can flow into the openings that receive the battery cells to retain 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 a 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. In addition, because the adhesive may contact the walls of the battery cell held within the cell carrier, less adhesive may be used to achieve a similar cohesion as compared to cell carriers where the adhesive is used on the outer surface or without an adhesive within the opening.

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

In this way, the amount of adhesive used to secure the battery cell 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 facilitate the manufacture of 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 an increase in adhesive flow rate and/or improved adhesion due to the additional surface area provided by the annular groove.

In this way, the solidified adhesive may interlock with the battery cell, providing a more secure securing arrangement. This may further allow for the use of less adhesive, for example by providing an annular ridge as described above, as the effective surface area of the battery cell that the adhesive contacts is increased. Other features and advantages of the present invention will become apparent from the following description of the preferred embodiments of the invention, given by way of example only, which is made with reference to the accompanying drawings.

Drawings

In order that the invention may be more readily understood, embodiments thereof will now be described, by way of example, with reference to the accompanying drawings, in which:

fig. 1 is a schematic diagram of an assembled battery pack according to one example;

fig. 2 is a schematic view of the 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 explanatory perspective view of an alternative example of the 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 top schematic 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 module 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 battery 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 cell according to FIG. 12A;

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

FIG. 14 is a schematic diagram of a battery module including a battery cell carrier according to FIG. 13 and a plurality of battery cells according to one example;

FIG. 15 is a flow chart 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 side schematic 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

The details of the methods and systems according to the 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, and certain features are omitted and/or necessarily simplified, in order to facilitate explanation and understanding of 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 forming at least part of a battery pack. The following description of the battery module and 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 delivery, 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 battery cells and respective bus bars. The battery cell carriers described herein may allow for precise and efficient positioning of the bus bars relative to the respective battery cells during assembly of the associated battery module. In other examples, current collectors are provided to conduct current along the smaller dimensions of a cell stack included in a battery module to provide an effective and reliable connection between adjacent battery modules. For a given cross-sectional area, conducting current along the smaller dimension of the group of battery cells may also allow for the use of thinner bus bars to connect the subsets of battery cells, which reduces weight and manufacturing costs. Shorter current paths may also reduce resistance in the bus bars, thereby improving efficiency. Having thinner busbars may also provide increased flexibility and therefore may result in higher reliability at the time of manufacture, for example, by laser welding the connections. Other examples described herein provide methods of constructing battery modules that include 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 an electric vehicle such as an electric automobile. In an electric vehicle, a 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 safe and reliable connections between the battery modules 110a to 110h so that the respective battery packs are resilient to stress and can maintain safe operation and electrical connection with a motor in the electric vehicle during use.

As shown in fig. 1, the battery modules 110a to 110h are fixed to the frame 120. The frame 120 holds the battery modules 110a to 110h in place in the arrangement. The battery modules 110 a-110 h may also be held in this arrangement by fasteners between adjacent battery modules, such as by using bolts or snap rings. Fig. 2 shows a similar arrangement of battery modules without 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 an electric vehicle that includes 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. Having the total current flow parallel to the first dimension 130, the larger dimension allows voltage to be added between the cell stacks along the major dimension of the battery pack 100 to provide the electrical 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 cell stack. The terms "battery cell" and "cell" are used interchangeably herein. The battery module 110a shown in fig. 2 has four unit battery packs 220a to 220 d. However, the battery module may generally have more or less unit battery packs than those shown in fig. 1 and 2. The actual battery cell is not shown in fig. 1 or fig. 2, but is shown in fig. 4A to fig. 8 later. The battery cells in each cell group 220 a-220 d are electrically connected in a combination of series and parallel connections within their respective cell group, for example using busbars or other suitable electrical connection mechanisms, as will be described. More specifically, in the arrangement of battery modules 200, each battery module 110 a-110 h is electrically connected to an adjacent battery module 110 a-110 h. 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 cell group 220a is electrically connected to the cell group 220e, and so on.

The arrangement 200 of battery modules shown in fig. 2 includes eight battery modules. However, it should be understood that the arrangement 200 may include any suitable number of battery modules. The exact number of battery modules in the arrangement 200 may depend on the intended use of the 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 cell groups 220 a-220 d. The battery module 110a includes a support member 320 having opposite first (upper) and second (lower) faces 320a, 320b on which the unit cell groups 220a/220b and the unit cell groups 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, 340 b. The cooling member has an internal conduit (not shown) through which a cooling fluid may be passed to 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 battery packs 220a and 220 b. Corresponding channels are shown between

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 the battery cell, for example by heating coolant flowing through the cooling member during use. This may be particularly useful, for example, when it is desired to pre-condition the battery cells, such as in the case of charging. Accordingly, the supporter 320 may be more generally considered as a heat transfer member.

Regardless of whether the supporter 320 performs the function of a cooling member, the supporter 320 is composed of a rigid material to carry the unit battery packs 220a to 220 d. 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 composite materials. The support 320 in this example is a planar member. In this context, the support 320 may be referred to as "planar" even if the surfaces of the faces are not completely planar, e.g., due to the accommodation of one or more features, which may be raised or recessed relative to other generally planar surfaces of the support. In this example, the supporter 320 is also shown as a generally regular rectangular plate-shaped member, supporting the cubic unit battery packs 220a to 220 d. The cell packs 220 a-220 d may be mounted to the support 320 by any suitable method, including but not limited to using adhesives, securing mechanisms such as clasps, clips, brackets, or any other suitable attachment mechanism.

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

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

Each cell group 220a to 220d includes a positive terminal connection and a negative terminal connection. In fig. 3, the

positive terminal connections

350a, 350b, 350d of the

respective cell stacks

220a, 220b, 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, the references to the positive and negative terminals may be reversed such that the current flow may be in the opposite direction to that described. In any case, the terminal connections of adjacent battery modules are physically joined and secured by suitable means, such as bolts and/or any other suitable attachment mechanism. In this example, the positive and negative terminal connections 350a to 360d each include a protrusion extending parallel to the plane of the support 320 to provide a convenient connection point for the respective cell stacks 220a to 220 d.

Fig. 4A shows a simplified schematic of the arrangement of battery cells 420 within a battery pack (e.g., cell pack 220a) according to one example. The 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 and shorter than the major dimension. The array 400 includes a plurality of sub-packs 410 a-410 d of battery cells 420, each sub-pack 410 a-410 d 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 410a to 410d are shown, although other numbers of subgroups, e.g. six or more, may be applied. In fig. 4A, subgroups 410 a-410 d are distinguished from adjacent subgroups 410 a-410 d using alternating white and shading. The number of unit cells in each of the sub-packs 410a to 410d may be the same or different among all the sub-packs 410a to 410 d. In some examples, a first set of a subset of the unit cells may include a first number of the unit cells, and a second set of the subset of the unit cells may include a second number of the unit cells, wherein the first number of the unit cells is different from the second number of the unit 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 cell group 220a in a direction parallel to the minor dimension. In other words, the battery cells 420 in the sub-packs 410a to 410d are connected in parallel with other battery cells 420 in the respective sub-packs 410a to 410d, and the sub-packs 410a to 410d are connected in series with the adjacent sub-packs 410a to 410 d. Causing the total current to flow in a direction parallel to the minor dimension of the cell group 220a in the battery module 110a distributes the current over the length of the battery module.

Fig. 4B illustrates a perspective view of the unit battery pack 220a of fig. 4A, in which like reference numerals are given

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

Shorter than the major dimension x of the array of battery cells 400 in the cell stack 410. The major dimension x of the array 400 is two to four times larger 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, battery cell 420 is elongated and may have any suitable cross-section along its length.

Fig. 5A shows a top view of the unit cell group 220a mounted on the support 320, which is a part of the battery module 110 a. The unit battery pack 220a is composed of sub-packs 410a to 410 d. In this view, the arrangement also includes a plurality of bus bars 500 a-500 c and

current collectors

510a and 510 b. The number of bus bars will depend on the number of subgroups of unit cells 410a to 410d, and in some examples, a battery module may include only one bus bar. Each bus bar 500 a-500 c includes a plurality of positive connection points (not shown) each connected to a respective positive terminal of the unit cells 420 in the first lower sub-group, thereby connecting the unit cells of that sub-group in parallel. Each bus bar 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 cell 420 in the second lower 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 sub-group to the negative terminal of the second sub-group, so that the sub-groups are connected in series with each other, and so that the total current flows in the corresponding battery module in parallel to the short axis of the unit battery group. The use of the bus bars to connect adjacent sub-packs of unit cells in this manner provides a convenient and reliable way of electrically connecting adjacent sub-packs of unit cells.

The

current collectors

510a and 510b serve to collect current from the respective sub-packs 410a and 410d of the unit cells located at the periphery of the unit cell group 220 a. Each

current collector

510a or 510b includes an electrical conductor having an edge that acts as a bus bar, spans the major dimension of the corresponding 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 the cells 420 in a 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 battery packs

220a, 220c disposed on opposite sides of a support 320. First and second

current collectors

510a, 510c are provided for collecting current from the sub-groups of the unit cells on the peripheries of the respective first and second

unit battery packs

220a, 220 c. The

current collectors

510a, 510c each include a

convergence region

530a and 530c that converges to a relatively narrow

electrical contact

520a and 520 c. In the example shown, the

electrical contacts

520a and 520c each include a protrusion from the respective

current collector

510a and 510c to provide a simple connection point through which electrical contacts of adjacent cell stacks may be juxtaposed and attached. These protrusions may be connected to additional protrusions by using any suitable attachment mechanism. For example, the bolts may be positioned through holes (not shown) in the protrusions and then may be fixed to additional protrusions of the adjacent unit battery packs. The projection projects in a direction parallel to the minor dimension. In this way, the electrical contact 520a extends toward the adjacent unit battery pack during assembly, and thus can be easily attached.

Each

electrical contact

520a, 520b (one is a positive terminal and the other is a negative terminal) of the respective cell stack 220a is used to electrically couple the respective cell stack 220a to another cell stack or to an output of a battery module 110a or battery pack including the cell stack 220 a. In some examples, the convergence zone 530a may converge to more than one electrical contact, e.g., to two or even three relatively narrow electrical contacts. Fig. 6A shows a first alternative example of a current collector 600 comprising a convergence area 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, 670 c. Such an arrangement may provide redundancy in the event of a failure of one of the

electrical contacts

670a, 670b, 670c, while still enabling the electrical contact to extend across only a portion of the length of the current collector 630. Current collectors such as those 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 collector 510a to a single electrical contact 520a simplifies the assembly of the battery module 110a, and thus may improve production efficiency. In addition, the single electrical contact 520a may increase the reliability of the connection between the battery modules and reduce the number of potential failure points. In the illustrative example of fig. 5A and 5B, current collectors 510a and 510B on opposite perimeters of cell stack 220a enable respective battery module 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 may be reduced. Thus, the

current collectors

510a and 510b including the protrusions may be at least partially flexible, thereby allowing simpler manufacturing of the battery module 110a while increasing elasticity against torsional stress. This may be beneficial when used in electric vehicles 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 vehicle components to bend. In this example, the

current collectors

510a and 510b are formed from a flexible and formable sheet of material, such as copper.

Returning to fig. 5B, each

current collector

510a, 510B, and 510c extends in a direction orthogonal to the major and minor dimensions of the cell stack. The orthogonal direction extends downward from the upper surface of each unit battery pack 220a or upward from the lower surface of each unit battery pack 220 c. This may allow the

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 in a direction orthogonal to the major dimension x and the minor dimension y, respectively, toward the support 320. 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 cell stack 220c 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 cell stacks (and the corresponding battery modules carrying the cell stacks) can be interconnected using a combination of busbars and current collectors, largely without resorting to more complex and possibly less reliable electrical connection schemes, including for example cables and wiring.

Because each

current collector

510a and 510b spans the length of the major dimension of the cell stack 220a, converging the

current collectors

510a and 510b in a direction orthogonal to the major and minor dimensions of the 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 transfer the total current across the major dimension to the

electrical contacts

520a and 520 b.

As shown in fig. 5A and 5B, the electrical contacts 520a, 520B, 520C are offset to either side of a central axis C located at the center of the array of battery cells 400, which is parallel to its minor dimension. The positions of the offset

electrical contacts

520a, 520b, and 520c allow the 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 (i.e., to the left of the central axis C as shown) in a second direction opposite the first direction. Having opposing, offset

electrical contacts

510a and 520c provides the desired electrical contacts with the appropriate size while maintaining electrical isolation between the first cell stack 220a and the second cell stack 220 c. This also allows the

current collectors

510a, 510b used on both sides of the cell group 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, since fewer types of components can be manufactured to produce the 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 manner, adjacent battery modules may be attached by their respective coplanar supports while providing a large contact area between adjacent electrical contacts.

In other examples, the

current collectors

510a, 510b, and 510c do not include

electrical contacts

520a, 520b, and 520c extending from the respective

current collectors

510a, 510b, and 510c, respectively, but rather include contact points. For example, there may be some other electrical attachment mechanism that may be used to connect adjacent cell packs. In some examples, the electrical contacts attached to opposing current collectors of a single cell battery may be different types of electrical connectors. For example, the current collector serving as the positive terminal may include a male connector, and the current collector serving as the negative terminal may include a female connector, so that the adjacent unit battery packs may be connected by attaching the respective negative terminals to the positive terminals of the adjacent unit battery packs. This may also prevent the positive terminal of the first cell stack from being accidentally connected to the positive terminal of the second cell stack.

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

Fig. 8 shows a view illustrating an arrangement 800 of four rows of assembled battery modules, such as the front four rows of assembled battery modules 110a through 110d of fig. 1 and 2. Fig. 8 shows in more detail that the supports of the individual battery modules are coplanar, which means that the upper and lower surfaces of the battery modules 110a to 110d are also coplanar in this case. For clarity, the connections are omitted in 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 the rows of adjacent subgroups parallel to the major dimension 130 of the stack (represented by arrows P, Q, R and S). The connection is such that current flows along the rows of the cell groups on the top and left side of the support in one direction P and along the rows of the cell groups below and left side of the support in the opposite direction Q. In this way, the rows of unit batteries may be conveniently connected in series at the ends of the battery pack 100 by the

connectors

830a, 830 b. In other examples, the

connectors

830a, 830b may be located at the other end of the battery pack 100, as desired. For example, in the illustrated example, the upper left row of the cell group is connected in series with the lower left row of the cell group, and the upper right row of the cell group is connected in series with the lower right row of the cell group. Alternatively, the upper left and upper right rows of the unit battery packs may be connected in series with each other, and the lower left and lower right rows of the unit battery packs may be connected in series with each other. In either case, it is convenient that all four rows of unit cell groups 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, with a positive terminal 1040 and a negative terminal 1050 located at the first end 1010. The openings in the battery cell carrier 910 are configured such that the first end 1010 of each battery cell 420 received in the opening is at least partially exposed through the battery cell carrier 910. This allows the positive terminal 1040 and the negative terminal 1050 of each cell to be connected by a respective bus bar 930. In some examples, only a portion of each of the positive terminal 1040 and the negative terminal 1050 of each cell 420 is exposed through the cell carrier 910 to prevent excessive corrosion or dust from affecting the cells 420. In other examples, the entire first end of each battery cell 420 is exposed through the battery cell carrier 910 so that the bus bar 930 can be easily connected to the terminals, 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 terminal, reducing the risk of poor connection. Having both the positive and

negative terminals

1040 and 1050 located on the first ends 1010 of the unit cells simplifies the construction of the battery module and requires the bus bar 930 to be located on only one side of the corresponding unit cell group.

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

Fig. 9B schematically shows end views (p, q) of two parallel connected banks of 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 securing feature 940 is visible, other examples may instead employ multiple securing features, such as across a major dimension of the battery cell carrier 910. In this example, the major dimension is defined as the size of the battery module that spans the maximum number of unit cells.

The use of the securing features 940 to position the bus bars 930 relative to the battery cell carrier 910 ensures that the position of the bus bars 930 relative to the position of the battery cells is accurately defined. The presence of the securing features 940 also means that the bus bars 930 can be effectively and accurately positioned for attaching the bus bars 930 to the battery cells 420 during manufacturing. The increased bus bar position accuracy due to the presence of the securing features 940 is also advantageous, in part, for using a cell 420 having positive and negative terminals on the same end 1010 of the cell 420. Inaccurate connection always causes a short circuit between the positive terminal 1040 and the negative terminal 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 battery 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 are deformed (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 bars 930 and the cell carrier 910 together.

Returning to fig. 10A and 10B, the battery cell 420 includes an annular groove 1030 around the upper perimeter of the battery cell 420, and the positive terminal 1040 and the negative terminal 1050 of the battery cell are coplanar. However, in other examples, one of the positive or

negative terminals

1040, 1050 may be raised or recessed 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 cell 420. In other embodiments, the terminals may be reversed such that the positive terminal forms a portion of the housing of the cell 420. Alternatively, the housing of the 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 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 adapted for use in a battery 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 respective one of a plurality of battery cells. Securing features such as securing

features

1110a, 1110b, and 1110c are included as upstanding projections on the upper surface 1120a of the battery cell carrier 1100. When the battery module is assembled, the upstanding projections engage the corresponding bus bars, thereby precisely aligning the bus bars with the 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 can be deformed by the application of heat and/or pressure to secure the respective bus bars to the battery cell carrier 1100. Once deformed, the upstanding projections 1110a to 1110c secure the bus bar to the cell carrier 1100.

Deformable fixation features 940 may be made of a suitable polymer or metal material. Alternatively, the securing features 940 may include fasteners or other mechanisms that may be attached to the bus bars. 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 end has been pressed into the corresponding securing hole 950 in the bus bar, at least a portion of the underside of the hemispherical end can engage the surface of the securing hole and prevent the bus bar from being removed.

Returning to fig. 11, the battery cell carrier 1100 is used to hold a plurality of battery cells 420 and includes an upper surface 1120a and a lower surface 1120 b. The battery cell carrier 1100 includes a plurality of walls 1130 extending between the upper surface 1120a and the lower surface 1120 b. Each of the plurality of walls 1130 at least partially defines an opening 1140 for receiving a respective one of the plurality of battery cells 420. Each opening 1140 in the battery cell carrier 1100 is configured to receive a respective 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 proximate or at the lower surface 1120 b. 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 comprises a rigid material that can provide support for the battery cells 420 mounted therein. The battery cell carrier 1100 may include a material that is softer than the surface material of the battery cells 420 so that the risk of the battery cell carrier 1100 damaging the battery cells 420 during manufacture and use is reduced. For example, the battery 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 a cell 420 is inserted into a respective one of the openings, the respective annular ridge 1150 engages the cell 420 and deforms in accordance with the cell 420. Annular ridge 1150 is sufficiently rigid that it continues to engage with cell 420 and at least partially hold cell 420 in place, such as by friction.

The annular ridges 1150 provide a secure fit between the cell 420 and the cell carrier 1100 that is received in a respective one of the openings 1140, thereby preventing the cell 420 from slipping and increasing stability. According to the present example, the annular ridges 1150 surround the respective openings 1140 and engage with the entire circumference of the unit cells 420.

In some examples, the battery cell 420 may be secured within the battery cell carrier 1100 by using a suitable adhesive. The adhesive contained in the openings 1140 contacts the cell walls of each battery cell and holds the battery cell in the battery cell carrier 1100. In this case, the annular ridge 1150 conveniently prevents adhesive from leaking down the respective cell 420, under 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 flat.

The wall 1130 includes a hole, such as hole 1170, between the respective opening 1140 and the recess 1160. Each hole 1170 fluidly connects a respective one of the openings 1140 to the recess 1160 such that during insertion of adhesive, adhesive flows from the recess 1160, through the hole 1170, and into the opening 1140. The hole 1170 has a boundary extending downward from the upper surface 1120 a. Adhesive flowing into openings 1140 flows around the cavities or regions between walls 1130 and the cell walls of battery cells 420 received in the respective openings 1140. Adhesive fills this area from the lower boundary defined by annular ridge 1150 and penetrates into annular groove 1030 of cell 420. The recess 1160 may be said to be in fluid communication with the cell walls of the battery cells 420 received in each respective opening in use. In the example shown in fig. 11, recess 1160 is configured such that during adhesive introduction, adhesive may flow through three apertures, including aperture 1170, and onto the walls of three respective battery 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. In the case 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 improve the speed and efficiency of manufacturing. Having the recess 1160 and hole 1170 arranged in this manner, and given a substantially free-flowing adhesive, allows gravity to draw in the adhesive and secure the cell 420 in a fixed arrangement without the need for 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 recess 1160. This may result in an increase in adhesive flow rate and/or improved adhesion due to the additional surface area provided by the annular recess 1030.

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

As noted, the adhesive is in fluid form prior to setting, such that the adhesive can be introduced into the recess 1160 using a suitable applicator. Thus, the adhesive flows under the action of gravity. Once applied, the adhesive begins to set, and after a certain 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 binder may have other properties, such as thermal conductivity, or may provide thermal insulation. In some examples, when set, adhesive may be disposed within the openings 1140 and in the corresponding holes 1170 and/or indentations 1160.

In some examples, the bus bars (not shown), which 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 1110a to 1110 c. This arrangement allows an adhesive to be introduced into the recesses to secure the cells 420 in the cell carrier 1100 once the bus bars are positioned with 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 the battery module associated therewith 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 circuit may include any number of sensors including, but not limited to, thermometers, voltmeters, ammeters, ohmmeters, accelerometers, and any other suitable sensors. The battery management circuitry may also include at least one controller including 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, the battery cell carrier 1100 holding or securing a plurality of battery cells 420 in their respective openings. In some embodiments, the at least one opening 1200 in the battery cell carrier 1100 is a virtual opening configured to impede insertion of the cell 420 therethrough. The virtual opening 1200 is located adjacent to and in fluid communication with the recess. The virtual opening may be used to maintain consistent adhesive fluid properties during the adhesive injection process. The consistency and behavior of the binder fluid can be tightly controlled, and thus the flow dynamics of the binder may be negatively affected in regions where the recesses are connected to fewer pores and thus in fluid communication with fewer cell walls. Accordingly, the dummy openings 1200 may be used to maintain adhesive flow characteristics in these areas.

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

Fig. 13 shows a simplified schematic of an alternative battery cell carrier 1300 according to one example. In this example, the cell carrier 1300 does not include securing features for positioning the bus bars, and the recess 1310 is in fluid communication with the two

openings

1320, 1330 only via

respective holes

1340, 1350 in the wall (e.g., wall 1360). Similar to that shown in fig. 11, the battery cell carrier 1300 includes an upper surface 1370 and a lower surface 1380, with the recess 1310 in the upper surface.

Fig. 14 shows the battery cell carrier of fig. 13 with a plurality of battery cells 420, such as battery cells 420 received in respective openings 1320. The annular grooves (not shown in this figure) of the cells 420 are configured to retain adhesive inserted through the

respective holes

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 over the annular ridge 1390 in the wall 1360 toward the hole 1340. In this manner, the adhesive may fill the annular groove 1030, which provides a greater surface area on the surface of the unit cell 420 to bond therewith. Further, in this and other examples, the annular groove 1030 provides greater resilience to the load exerted on the cell 420 or the cell carrier 1300.

Fig. 15 shows a flow diagram 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, 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 an adhesive into the recess, such that the adhesive flows out of the recess, through the aperture, and into the opening, and such that, when solidified, the adhesive retains the plurality of battery cells 420 in the battery 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 a 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 lower side of electric vehicle 1600 so as to lower the center of mass of electric vehicle 1600. Fig. 17 shows a schematic top view of an electric vehicle 1700 according to an example. The electric vehicle 1700 includes a front electric drive unit cell 1710 and a rear electric drive unit cell 1720 for delivering power to at least one drive wheel 1730 of the electric vehicle 1720. The vehicle 1700 includes a battery pack 1740, the battery pack 1740 being located between the front and rear electrically driven

unit cells

1710, 1720. In this example, the front and rear electric

drive unit batteries

1710, 1720 include inverters to convert the DC battery current to AC current for delivery to the traction motors. In the illustrated embodiment, the battery pack 1740 includes an electrical connection 1750 for connecting the battery pack to the rear electric drive unit cell 1720. The battery pack 1740 may also have electrical connections to the front drive cell 1730. In some examples, the battery pack 1740 is arranged such that the battery input/output 1760 is positioned towards the front electric drive unit battery 1710 of the electric vehicle 1700, and the electrical connections 1750 extend from the battery input/output 1760 along the channels to the rear electric drive unit battery 1720. Electrical connection 1750 is connected to the inverter of the rear electric 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 battery 1710 or to a charging port of the electric vehicle 1700 may extend along a passageway of the battery pack 1740. In other examples, the battery input/output 1760 may be located anywhere else on the battery pack 1740, such as toward the rear electric drive unit battery 1720 of the electric vehicle 1700 in which it is used.

The above-described embodiments are to be understood as illustrative examples of the 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.

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

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

4. The battery cell carrier of 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 adhesive within an opening.

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

8. The battery cell carrier of 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. The battery cell carrier of any preceding claim, wherein the battery cell carrier comprises at least one first securing feature for engaging 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 hole for engaging the at least one upstanding protrusion.

11. The battery cell carrier of claim 10, wherein the upstanding projections are deformable to secure the bus bars to the battery cell carrier.

12. The battery cell carrier of any preceding claim comprising a plurality of recesses for receiving adhesive, each recess fluidly connected 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 surface and the lower surface, each opening receiving one of the plurality of battery cells, each opening including an annular ridge; and

a recess in the upper surface for receiving adhesive;

wherein a 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, an

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 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 an adhesive inserted through the aperture.

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

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

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

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 surface and the lower surface, each opening including an annular ridge;

a recess in the upper surface for receiving adhesive, wherein a 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 corresponding one of the openings;

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

curing the adhesive 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.