Battery electronics module

Abstract

A battery electronics module 100 for a vehicle, comprising a casing 12 enclosing one or more electronic components, one or more high voltage busbars 102 mounted inside the casing adjacent to an intern

Description

TECHNICAL FIELD The present disclosure relates to a battery electronics module. Aspects of the invention relate to a battery electronics module, to a battery electronics module housing apparatus, to a vehicle battery system, and to a vehicle. BACKGROUND A known battery system for electric vehicles (EVs) includes a battery, and a battery electronics module which contains various electronic components for controlling distribution of power to / from the battery (e.g., high voltage busbars, electrical contacts, AC / DC converters, control modules, charge modules etc.). For example, the battery electronics module may be used to distribute power from the battery to electrical consumers of the vehicle (e.g., EDUs, electric motors, etc.). The battery electronics module may also be used to direct power from a charging source to be stored in the battery. The electronic components within the battery electronics module can generate significant amounts of heat during operation. This heat, if not properly managed, can lead to reduced efficiency of the battery system. It is an aim of the present invention to address one or more of the disadvantages associated with the prior art. SUMMARY OF THE INVENTION Aspects and embodiments of the invention provide a battery electronics module, a battery electronics module housing apparatus and a vehicle as claimed in the appended claims. According to an aspect of the present disclosure there is provided a battery electronics module. The battery electronics module comprises a casing which defines an enclosure for one or more electronic components. The battery electronics module also comprises one or more electronic components mounted inside the enclosure adjacent to an internal surface of the casing. The battery electronics module also comprises a casing cooling arrangement provided outside the enclosure. The casing cooling arrangement comprises one or more cooling channels and is configured to receive a flow of cooling fluid through the one or more cooling channels for cooling the casing and thereby cooling the one or more electronic components. By having the casing cooling arrangement provided outside the enclosure, no cooling fluid is required inside the enclosure. This reduces complexity since there is no need to provide a cooling fluid connection through casing. In addition, this protects electronic components inside the enclosure from damage in the event of leaking cooling fluid. In addition, good cooling performance of the one or more electronics components can still be achieved by mounting them adjacent to the internal surface of the casing and then cooling the casing. In this context, the phrase “adjacent to” will be understood to mean proximal to, but not necessarily directly touching. For example, there may be thin and / or non-structural components in between the one or more electronic components and the internal surface of the casing. Optionally, the one or more electronic components comprise one or more high voltage busbars. High voltage busbars and associated electrical contacts are components which typically generate large amounts of heat. Thus, by having the one or more high voltage busbars mounted adjacent to the internal surface of the casing along with such a casing cooling arrangement, the high voltage busbars and associated electrical contacts can be cooled. This may allow downsizing of the one or more high voltage busbars and thus a more compact battery electronics module. Optionally, the one or more cooling channels are substantially aligned with the one or more high voltage busbars. In this context, the phrase “substantially aligned” will be understood to mean that the one or more cooling channels approximately follow a path or shape of the one or more high voltage busbars. Put another way, the one or more cooling channels may run close to the one or more high voltage 1 busbars. For example, the one or more high voltage busbars and one or more cooling channels may be positioned proximal to each other in plan view (e.g., may overlap at least partially in plan view). Optionally, the one or more cooling channels are provided in the casing. By providing the one or more cooling channels in the casing, the one or more cooling channels can be positioned closer to the enclosure than alternatives such as external pipes adjacent to the casing. This may lead to improved cooling performance. In addition, this may provide a more compact casing cooling arrangement, simplified assembly, reduced component count, and a reduction in fluid tight connections that need to be effected and checked. Optionally, the one or more cooling channels are provided in an external surface of the casing. Optionally, the battery electronics module further comprises a covering coupled to the external surface of the casing to cover the one or more cooling channels. Such a configuration of the one or more cooling channels can easily be manufactured, and can be used to produce complex cooling channel shapes that would be difficult to achieve via other constructions. For example, the one or more cooling channels can be cast into the external surface of the casing in a more complex shape than would be possible using internal casting cores. Similarly, the one or more cooling channels can be machined into the external surface of the casing more easily and / or with a more complex shape than would be possible via internal machining. Optionally, the covering is welded to the external surface of the casing. This provides a simple means of closing and sealing the one or more cooling channels. Optionally, the covering is welded to the external surface of the casing via friction stir welding. Friction stir welding may be particularly effective for sealing the one or more cooling channels since it limits porosity and deformation in the covering in comparison to alternative types of welding. Optionally, the covering is secured to the external surface using one or more fasteners. Optionally, the battery electronics module comprises a seal (e.g., compressible gasket) between the covering and the external surface. Optionally, the covering is secured to the external surface of the casing by an adhesive or sealant. Optionally, the casing comprises a shoulder in the external surface, wherein the shoulder at least partly surrounds the one or more cooling channels and is configured to receive a periphery of the covering. Such a shoulder may improve sealing of the one or more cooling channels (e.g., by providing a more tortuous path than if the covering was mounted over a flat surface). In addition, such a shoulder defines a recessed space which may allow the covering to be provided flush with the rest of the external surface of the casing. Further, such a shoulder facilitates alignment of the covering during assembly. Optionally, the covering comprises an inner side adjacent the one or more cooling channels and an outer side. Optionally, the outer side has one or more fins, ridges or other structures to increase the surface area of the outer side of the covering. This may facilitate improved transfer of heat from the covering to ambient air, in addition to the cooling fluid flowing through the one or more cooling channels. In alternative embodiments, the one or more cooling channels are provided within the casing (i.e., between the external and internal surfaces of the casing). In such embodiments, the one or more cooling channels may be cast into the casing (e.g., using casing cores), machined and / or produced via additive manufacturing. Optionally, the casing cooling arrangement comprises a plurality of cooling channels. Having a plurality of cooling channels increases cooling performance in comparison to a casing cooling arrangement with a single cooling channel of similar size. In addition, having a plurality of separate cooling channels allows cooling to be targeted at key hotspots more easily than would be possible with a single wider cooling channel. Optionally, the casing cooling arrangement comprises a common casing inlet for inflow of cooling fluid to the plurality of cooling channels and / or a common casing outlet for outflow of cooling fluid from the plurality of cooling channels. Such a common casing inlet and / or common casing outlet simplifies connections to a cooling fluid circuit in comparison to arrangements with dedicated inlets and / or outlets for each channel. Optionally, at least some of the plurality of cooling channels merge together at a confluence region, so that the number of cooling channels varies along a length of the casing. Such a configuration may facilitate improved cooling by having more cooling channels at hot spots which generate more heat, and better structural integrity by having fewer cooling channels at colder regions of the casing. Optionally, each of the plurality of cooling channels is separated from one or more adjacent cooling channels by a channel wall. Optionally, the channel wall has a bulbous end at the confluence region. This may facilitate mixing of cooling fluid at the confluence region. Optionally, the one or more cooling channels are configured to direct cooling fluid along a length of the casing. Optionally, a width of the one or more cooling channels varies along the length of the casing. Such a configuration may facilitate improved cooling by having a greater width at hot spots which generate more heat, and better structural integrity by having a narrower width at colder regions of the casing. Optionally, the casing cooling arrangement is configured to provide a higher rate of cooling in the casing proximal to the one or more high voltage busbars and associated electrical contacts than at other portions of the casing. Such a configuration provides a good tradeoff between increased cooling where it is needed, and increased structural integrity where cooling requirements are lower. Optionally, the casing is an elongate casing. It will be understood that, for a given enclosure area, an elongate casing provides a larger internal surface for transfer of heat from the one or more high voltage busbars to the casing cooling arrangement than in less elongate alternatives. Optionally, a length of the casing is greater than a height of the casing. Optionally, the length of the casing is at least 2 times greater than the height of the casing, optionally at least 3 times greater, optionally at least 4 times greater, optionally at least 5 times greater. It will be understood that, for a given enclosure area, such a casing provides a larger internal surface for transfer of heat from the one or more high voltage busbars to the casing cooling arrangement than in alternatives in which the height and length of the casing are more similar in size. Optionally, the one or more cooling channels have a length in a range of about 50 mm to about 1100 mm. Optionally, the one or more cooling channels have a width in a range of about 10 mm to about 150 mm. Optionally, the one or more cooling channels have a depth in a range of about 3 mm to about 12 mm. Optionally, the casing has a length in a range of about 600 mm to about 1200 mm. Optionally, the casing has a width in a range of about 100 mm to about 200 mm. Optionally, the casing has a height in a range of about 80 mm to about 150 mm. In alternative embodiments, the one or more cooling channels are defined by one or more cooling pipes positioned proximal to an external surface of the casing. Optionally, the casing cooling arrangement is in fluid communication with an internal cooling arrangement provided within the enclosure. For example, the casing cooling arrangement may be provided in series with the internal cooling arrangement as part of the same cooling flow path. For example, there may be a single common casing inlet and / or single common casing outlet for the cooling flow path. For example, cooling fluid may be input via the common casing inlet, then through part of the casing cooling arrangement, then through the internal cooling arrangement, then through another part of the casing cooling arrangement, then out of the common casing outlet. Other cooling flow paths may also be used. Having such an internal cooling arrangement provided within the enclosure may allow higher level of cooling for particular dedicated components inside the enclosure. In addition, by providing the casing cooling arrangement in fluid communication with the internal cooling arrangement (i.e., as part of the same cooling flow path) may simplify cooling fluid connections in comparison to alternatives where the casing cooling arrangement and internal cooling arrangement are separate from each other. Optionally, the casing has a thermal conductivity of at least 100 W / mK, optionally at least 150 W / mK, optionally at least 200 W / mK. Such a thermal conductivity facilitates good heat transfer from the high voltage busbars mounted adjacent to the internal surface of the casing to the cooling fluid flowing within the one or more cooling channels. Optionally, the casing is formed of a metallic material. Metallic material provides good structural integrity as well as good thermal conductivity. In addition, metallic material may be easily cast to the required shape. Optionally, the casing is formed of an aluminium alloy material. Aluminium alloy material offers a particularly good tradeoff between cost, structural integrity, thermal conductivity and weight. In some embodiments, the casing is formed as a cast metal body (e.g., a cast aluminium alloy body). In other embodiments, the casing is forged or produced via additive manufacturing. Optionally, the casing comprises a structure having a base portion for mounting the one or more electronic components and a cover portion releasably coupled to the base portion. Such a structure simplifies manufacturing and / or maintenance / repair (i.e., by releasing the cover portion to access the electronic components in the enclosure. Optionally, the casing cooling arrangement is configured to cool the base portion. Having cooling on the base portion (where components are mounted adjacent to) improves cooling compared to having cooling on the cover portion. Optionally, the battery electronics module further comprises a thermal interface material provided between the one or more high voltage busbars and the internal surface of the casing. Such a thermal interface material facilitates heat transfer from the one or more high voltage busbars and the cooling fluid flowing within the one or more cooling channels. Optionally, the thermal interface material has a thermal conductivity of at least 0.5 W / mK, optionally at least 1 W / mK, optionally at least 2 W / mK, optionally at least 3 W / mK, optionally at least 4 W / mK, optionally at least 5 W / mK, optionally at least 6 W / mK, optionally at least 7 W / mK, optionally at least 8 W / mK, optionally at least 9 W / mK, optionally at least 10 W / mK. Optionally, the thermal interface material is electrically insulating. Such a thermal interface material inhibits conduction of electricity from the one or more electronic components (e.g. high voltage busbars) to the casing. Optionally, the thermal interface material has a volume resistivity volume resistivity of at least 109Q.cm, optionally at least 1010Q.cm, optionally at least 1011Q.cm, optionally at least 1012Q.cm, optionally at least 1013Q.cm. Optionally, the thermal interface material has a breakdown voltage of at least 1 Kv / mm, optionally at least 2 Kv / mm, optionally at least 3 Kv / mm, optionally at least 4 Kv / mm, optionally at least 5 Kv / mm, optionally at least 6 Kv / mm. It will be understood that, where the thermal interface material is both electrically insulating and thermally conducting, the thermal interface material provides two separate functions of facilitating heat transfer to the casing cooling arrangement and inhibiting conduction of electricity to the casing. Optionally, the thermal interface material comprises ceramic filled silicone material (e.g., TP-300). Such a thermal interface material provides a good combination of thermal conductivity and electrical insulation. Optionally, the thermal interface material has a thickness in a range of about 0.5mm to about 10mm. Such a thickness may provide a good tradeoff between having adequate electrical insulation as well as good thermal conductivity. Optionally, the battery electronics module further comprises an electrical insulation material provided between the one or more high voltage busbars and the internal surface of the casing. Such an electrical insulation material inhibits conduction of electricity from the one or more high voltage busbars and the casing, which may be particularly useful when the casing is made of metallic material. Optionally, the electrical insulation material is provided between a thermal interface material and the internal surface of the casing. In such configurations, the electrical insulation material provides backup insulation protection (i.e., double protection) in the event of any issues with the electrical insulation of the thermal interface material. Optionally, the electrical insulation material comprises an electrical tape material. Optionally, the electrical tape material comprises an acrylic adhesive. Optionally, the electrical insulation material comprises a polyimide film material. Optionally, the electrical insulation material has a thickness in a range of about 0.01 mm to 0.2 mm, optionally in a range of about 0.03 mm to 0.1 mm, optionally in a range of about 0.05 mm to 0.09 mm. Optionally, the electrical insulation material has an insulation resistance of at least 103 MQ, optionally at least 104 MQ, optionally at least 105 MQ, optionally at least 106 MQ. Optionally, the battery electronics module further comprises an internal cover configured to isolate the high voltage busbars mounted adjacent to the internal surface of the casing from one or more additional electronic components provided inside the enclosure above the one or more high voltage busbars. Such an internal cover allows the one or more high voltage busbars to be mounted underneath other components (improving cooling of the one or more high voltage busbars), whilst making use of space within the enclosure above the one or more high voltage busbars. Optionally, the internal cover is configured to urge the one or more high voltage busbars towards the internal surface of the casing. This improves heat transfer (e.g., by compressing a thermal interface material positioned between the one or more high voltage busbars and the internal surface). Optionally, the internal cover is electrically insulating. This inhibits malfunction to the one or more components mounted above the internal cover, by inhibiting unwanted conduction of electricity from the one or more high voltage busbars. Optionally, the internal cover comprises a thermal interface material. This may facilitate transfer of heat from the one or more components mounted above the cover to the casing and thus to the cooling fluid flowing through the one or more cooling channels. In such embodiments, the thermal interface material may be electrically insulating as well as thermally conductive (e.g., of a similar material to the thermal interface material provided between the one or more high voltage busbars and the internal surface of the casing, described above). 5 Optionally, the internal cover is made of plastics material. Optionally, the one or more additional electronic components comprise a battery electronics control module. Optionally, the battery electronics module further comprises a cooling fluid source in fluid communication with the casing cooling arrangement. For example, a cooling fluid reservoir and a pump configured to circulate cooling fluid from the cooling fluid reservoir through the casing cooling arrangement. A further aspect of the disclosure provides a battery electronics module housing apparatus. The battery electronics module housing apparatus comprises a casing which defines an enclosure for one or more electronic components. The casing comprises an internal surface for mounting the one or more electronic components within the enclosure. The battery electronics module housing apparatus also comprises a casing cooling arrangement provided outside the enclosure. The casing cooling arrangement is configured to receive a flow of cooling fluid for cooling the casing and thereby cooling the one or more electronic components. By having such a casing cooling arrangement, one or more electronic components mounted adjacent to the internal surface of the casing can be cooled. In addition, by having the casing cooling arrangement provided outside the enclosure, no cooling fluid is required inside the enclosure. This reduces complexity since there is no need to provide a cooling fluid connection through casing. In addition, this protects electronic components inside the enclosure from damage in the event of leaking cooling fluid. In addition, good cooling performance of electronic components can still be achieved by mounting the electronic components adjacent to the internal surface of the casing and then cooling the casing. Optionally, the one or more cooling channels are provided in the casing. Optionally, the one or more cooling channels are provided in an external surface of the casing. Optionally, the battery electronics module housing apparatus further comprises a covering coupled to the external surface of the casing to cover the one or more cooling channels. Such a configuration of the one or more cooling channels can easily be manufactured, and can be used to produce complex cooling channel shapes that would be difficult to achieve via other constructions. For example, the one or more cooling channels can be cast into the external surface of the casing in a more complex shape than would be possible using internal casting cores. Optionally, the covering is welded to the external surface of the casing; optionally via friction stir welding. Optionally, the covering is secured to the external surface using one or more fasteners. Optionally, the battery electronics module housing apparatus comprises a seal (e.g., compressible gasket) between the covering and the external surface. Optionally, the covering is secured to the external surface of the casing by an adhesive or sealant. Optionally, the casing comprises a shoulder in the external surface, wherein the shoulder at least partly surrounds the one or more cooling channels and is configured to receive a periphery of the covering. Optionally, the covering comprises an inner side adjacent the one or more cooling channels and an outer side, the outer side having one or more fins, ridges or other structures to increase the surface area of the outer side of the covering. In alternative embodiments, the one or more cooling channels are provided within the casing (i. e., between the external and internal surfaces of the casing). In such embodiments, the one or more cooling channels may be cast into the casing (e.g., using casing cores), machined and / or produced via additive manufacturing. Optionally, the casing cooling arrangement comprises a plurality of cooling channels. Optionally, the casing cooling arrangement comprises a common casing inlet for inflow of cooling fluid to the plurality of cooling channels and / or a common casing outlet for outflow of cooling fluid from the plurality of cooling channels. Optionally, at least some of the plurality of cooling channels merge together at a confluence region, so that the number of cooling channels varies along a length of the casing. Optionally, each of the plurality of cooling channels is separated from one or more adjacent cooling channels by a channel wall. Optionally, the channel wall has a bulbous end at the confluence region. Optionally, the one or more cooling channels are configured to direct cooling fluid along a length of the casing. Optionally, a width of the one or more cooling channels varies along the length of the casing. Optionally, the casing is an elongate casing. Optionally, a length of the casing is greater than a height of the casing. Optionally, the length of the casing is at least 2 times greater than the height of the casing, optionally at least 3 times greater, optionally at least 4 times greater, optionally at least 5 times greater. Optionally, the one or more cooling channels have a length in a range of about 50 mm to about 1100 mm. Optionally, the one or more cooling channels have a width in a range of about 10 mm to about 150 mm. Optionally, the one or more cooling channels have a depth in a range of about 3 mm to about 12 mm. Optionally, the casing has a length in a range of about 600 mm to about 1200 mm. Optionally, the casing has a width in a range of about 100 mm to about 200 mm. Optionally, the casing has a height in a range of about 80 mm to about 150 mm. In alternative embodiments, the one or more cooling channels are defined by one or more cooling pipes positioned proximal to an external surface of the casing. Optionally, the casing cooling arrangement is in fluid communication with an internal cooling arrangement provided within the enclosure. Optionally, the casing has a thermal conductivity of at least 100 W / mK, optionally at least 150 W / mK, optionally at least 200 W / mK. Optionally, the casing is formed of a metallic material; optionally an aluminium alloy material. In some embodiments, the casing is formed as a cast metal body (e.g., a cast aluminium alloy body). In other embodiments, the casing is forged or produced via additive manufacturing. Optionally, the casing comprises a structure having a base portion for mounting the one or more electronic components and a cover portion releasably coupled to the base portion. Optionally, the casing cooling arrangement is configured to cool the base portion. Optionally, the battery electronics module housing apparatus comprises a thermal interface material provided adjacent to the internal surface of the of the casing. Optionally, the thermal interface material has a thermal conductivity of at least 0.5 W / mK, and the thermal interface material is electrically insulating. Optionally, the thermal interface material has a thermal conductivity of at least 0.5 W / mK, optionally at least 1 W / mK, optionally at least 2 W / mK, optionally at least 3 W / mK. Optionally, the thermal interface material is electrically insulating. Optionally, the thermal interface material has a volume resistivity volume resistivity of at least 109Q.cm, optionally at least 1010Q.cm, optionally at least 1011Q.cm, optionally at least 1012Q.cm, optionally at least 1013Q.cm. Optionally, the thermal interface material has a breakdown voltage of at least 1 Kv / mm, optionally at least 2 Kv / mm, optionally at least 3 Kv / mm, optionally at least 4 Kv / mm, optionally at least 5 Kv / mm, optionally at least 6 Kv / mm. Optionally, the thermal interface material comprises ceramic filled silicone material (e.g., TP-300). Optionally, the thermal interface material has a thickness in a range of about 0.5mm to about 10mm. Optionally, the battery electronics module housing apparatus comprises an electrical insulation material provided adjacent to the internal surface of the casing. Optionally, the electrical insulation material is provided between a thermal interface material and the internal surface of the casing. Optionally, the electrical insulation material comprises an electrical tape material. Optionally, the electrical tape material comprises an acrylic adhesive. Optionally, the electrical insulation material comprises a polyimide film material. Optionally, the electrical insulation material has a thickness in a range of about 0.01 mm to 0.5 mm, optionally in a range of about 0.03 mm to 0.2 mm, optionally in a range of about 0.05 mm to 1 mm. Optionally, the electrical insulation material has an insulation resistance of at least 103 MQ, optionally at least 104 MQ, optionally at least 105 MQ, optionally at least 106 MQ. A further aspect of the disclosure provides a vehicle battery system comprising a battery electronics module as disclosed herein, and a battery. Such a vehicle battery system benefits from the advantages of the battery electronics module and / or housing apparatus outlined above. Optionally, the battery electronics module is mounted on an upper surface of the battery. A further aspect of the disclosure provides a vehicle comprising a battery electronics module as disclosed herein and / or a battery electronics module housing apparatus as disclosed herein and / or a vehicle battery system as disclosed herein. Such a vehicle benefits from the advantages of the battery electronics module and / or housing apparatus and / or vehicle battery system outlined above. Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and / or features of any embodiment can be combined in any way and / or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and / or incorporate any feature of any other claim although not originally claimed in that manner. BRIEF DESCRIPTION OF THE DRAWINGS One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a plan view of a vehicle in accordance with an embodiment of the invention; Figure 2 shows a rear view of the vehicle of Figure 1; Figure 3 shows a lateral cross-sectional view of a battery electronics module for the vehicle of Figures 1 and 2, in accordance with an embodiment of the invention; Figure 4 shows a longitudinal cross-sectional view of the battery electronics module of Figure 3; Figure 5 shows an underside view of a battery electronics module for the vehicle of Figures 1 and 2, in accordance with an embodiment of the invention; Figure 6 shows an enlarged, exploded cross-sectional view of the battery electronics module of Figure 5; Figure 7 shows a schematic diagram of a cooling flow path through the battery electronics module of Figures 5 and 6; and Figure 8 shows a side view of a covering for the battery electronics module of Figures 3 and 4, according to an embodiment of the invention. DETAILED DESCRIPTION Battery electronics modules in accordance with embodiments of the present invention are described herein with reference to the accompanying Figures 1 to 8. Figures 1 and 2 illustrate a vehicle 200 having a vehicle battery system 202. The vehicle battery system 202 includes a battery 204 and a battery electronics module 100. In Figures 1 and 2, the battery 204 and battery electronics module 100 are illustrated schematically by dashed lines. In the schematic illustration of Figures 1 and 2, the battery electronics module 100 is mounted on an upper surface 206 of the battery 204. However, in other embodiments the battery electronics module 100 may be positioned below, above, to either side, behind or in front of the battery 204. Referring now to Figures 3 and 4, a battery electronics module 100 which can be used in the vehicle battery system 202 of Figures 1 and 2 is illustrated. Figure 3 shows a lateral cross-section through plane A-A illustrated on Figure 4. Figure 4 shows a longitudinal cross-section taken through plane B-B illustrated on Figure 3. The battery electronics module 100 includes a housing apparatus 10 which has a casing 12 and a casing cooling arrangement 40. The casing 12 defines an enclosure 14 for one or more electronic components. In particular, the casing 12 has an internal surface 16 for mounting one or more electronic components within the enclosure 14. In the illustrated embodiment, one or more high voltage busbars 102 are provided inside the enclosure 14, mounted adjacent to the internal surface 16 of the casing 12. In this context, the phrase “adjacent to” will be understood to mean proximal to, but not necessarily directly touching. For example, as described in more detail below, there may be thin and / or non-structural components in between the one or more high voltage busbars 102 and the internal surface 16 of the casing 12. Figures 3 and 4 both illustrate two high voltage busbars 102, but other numbers of high voltage busbars 102 may be used. In some embodiments, alternative types of electronic components may be mounted adjacent to the internal surface 16 of the casing 12 in addition to or instead of the high voltage busbars 102. The casing cooling arrangement 40 is configured to receive a flow of cooling fluid for cooling the casing 12.1 n this way, the casing cooling arrangement 40 is also configured to cool the high voltage busbars 102 (and / or other electronic components) which are provided adjacent the internal surface 16 of the casing 12. In particular, heat may be transferred from the high voltage busbars 102 to the casing 12, and then to the cooling fluid flowing through the casing cooling arrangement 40. High voltage busbars 102 and associated electrical contacts 104 are components which typically generate large amounts of heat. Thus, by having such a casing cooling arrangement 40, the high voltage busbars 102 and associated electrical contacts 104 can be cooled. This may allow downsizing of the high voltage busbars 102 and thus a more compact battery electronics module 100. As will be described in more detail below, the casing cooling arrangement 40 is provided outside the enclosure 14, so that no cooling fluid is required inside the enclosure 14 in order to cool the high voltage busbars 102. This reduces complexity since there is no need to provide a cooling fluid connection through casing 12 in order to cool the high voltage busbars 102. In addition, this protects electronic components inside the enclosure 14 from damage in the event of leaking cooling fluid. In addition, good cooling performance of the high voltage busbars 102 can still be achieved by mounting the high voltage busbars 102 adjacent to the internal surface 16 of the casing 12 and then cooling the casing 12. The casing cooling arrangement 40 has one or more cooling channels 42 for receiving the flow of cooling fluid. For example, Figure 4 illustrates a cooling flow path 54 (shown as arrows) which passes through a casing inlet 56. The casing inlet 56 extends through the casing 12 and is in fluid communication with the one or more cooling channels 42. In this way, cooling fluid can be input to the one or more cooling channels 42 through the casing inlet 56. The cooling flow path 54 also passes through a casing outlet 58. The casing outlet 58 extends through the casing 12, and is in fluid communication with the one or more cooling channels 42. In this way, cooling fluid can be expelled from the one or more cooling channels 42 via the casing outlet 58. In some embodiments, the casing cooling arrangement 40 has a plurality of cooling channels 42. For example, in Figure 3 there are two cooling channels 42, which are separated by a channel wall 68. In other embodiments, there may be a single cooling channel 42 or more than two cooling channels 42. In embodiments where the casing cooling arrangement 40 has a plurality of cooling channels 42, the casing inlet 56 may be a common casing inlet for inflow of cooling fluid to the plurality of cooling channels 42. Similarly, the casing outlet 58 may be a common casing outlet for outflow of cooling fluid from the plurality of cooling channels 42. In the embodiment of Figures 3 and 4, the cooling channels 42 are substantially aligned with the high voltage busbars 102. In this context, the phrase “substantially aligned” will be understood to mean that the cooling channels 42 approximately follow a path or shape of the high voltage busbars 102. Put another way, the cooling channels 42 may run close to the high voltage busbars 102. For example, in Figure 3 each of the cooling channels 42 overlaps a respective high voltage busbar 102. For example, the cooling channels 42 are provided vertically below the high voltage busbars 102. In other embodiments, the cooling channels 42 may only partially overlap the high voltage busbars 102. For example, only a portion of the cooling channels 42 may be vertically below the high voltage busbars 102, with another portion of the cooling channels 42 being offset laterally to the side of the high voltage busbars 102. In other embodiments, the cooling channels 42 may not overlap the high voltage busbars 102 at all, e.g., the cooling channels 42 may instead be positioned proximal to the high voltage busbars 102, but laterally spaced apart therefrom. In the illustrated embodiment, the cooling channels 42 are provided in the casing 12. This allows the cooling channels 42 to be positioned closer to the enclosure 14 than alternatives such as external pipes adjacent to the casing 12. This may lead to improved cooling performance. In addition, this may provide a more compact casing cooling arrangement 40, simplified assembly, reduced component count, and a reduction in fluid tight connections that need to be effected and checked. In the illustrated embodiment, the cooling channels 42 are provided in an external surface 18 of thecasing 12 (e.g., recessed into the external surface 18). A covering 44 is coupled to the external surface 18 of the casing 12 to cover the cooling channels 42. In other words, the cooling channels 42 are open channels formed in the external surface 18 of the casing 12, and the covering 44 closes the open channels. Such a configuration of the cooling channels 42 can easily be manufactured, and can be used to produce complex cooling channel shapes that would be difficult to achieve via other constructions. For example, the cooling channels 42 can be cast into the external surface 18 of the casing 12 in a more complex shape than would be possible using internal casting cores. Similarly, the cooling channels 42 can be machined into the external surface 18 of the casing 12 more easily and / or with a more complex shape than would be possible via internal machining. In the illustrated embodiment, the casing 12 has a shoulder 20 in the external surface 18 of the casing 12. The shoulder 20 at least partly surrounds the cooling channels 42, and is configured to receive a periphery 46 of the covering 44. Such a shoulder 20 may improve sealing of the cooling channels 42 (e.g., by providing a more tortuous path than if the covering 44 was mounted over a flat surface). In addition, such a shoulder 20 defines a recessed space which allows the covering 44 to be provided flush with the rest of the external surface 18 of the casing 12 (as illustrated in Figures 3 and 4). Further, such a shoulder 20 facilitates alignment of the covering 44 during assembly. In some embodiments, the covering 44 is welded to the external surface 18 of the casing 12. For example, friction stir welding may be used, which is particularly beneficial since it limits porosity and deformation in the covering 44 in comparison to alternative types of welding. In other embodiments, the covering 44 is secured to the external surface 18 of the casing 12 using one or more fasteners. In such embodiments, a seal (e.g., compressible gasket) may be provided between the covering 44 and the external surface 18. In other embodiments, the covering 44 is secured to the external surface 18 of the casing 12 by an adhesive or sealant. The covering 44 has an inner side 48 adjacent the cooling channels 42 and an outer side 50. In the embodiment of Figures 3 and 4, the outer side 50 of the covering 44 is substantially flat. This facilitates mounting the battery electronics module 100 on the upper surface 206 of the battery 202. In other embodiments, the outer side 50 of the covering 44 has one or more fins, ridges or other structures to increase the surface area of the outer side 50 of the covering 44. For example, an alternative covering 44 having a plurality of fins 52 is illustrated in Figure 8. This may facilitate improved transfer of heat from the covering 44 to ambient air, in addition to the cooling fluid flowing through the cooling channels 42. In alternative embodiments, the cooling channels 42 are provided within the casing 12. In other words, the cooling channels maybe provided between the internal and external surfaces 16, 18 of the casing 12, instead of in the external surface 18 and closed by a separate covering 44. In such embodiments, the cooling channels 42 may be cast into the casing 12 (e.g., using casing cores), machined and / or produced via additive manufacturing. The casing 12 has a length 22 (illustrated in Figure 4), a width 24 (illustrated in Figure 3) and a height 26 (illustrated in Figure 3). In the embodiment of Figures 3 and 4, the casing 12 is an elongate casing. I n other words, the length 22 of the casing 12 is greater than the width 24 and / or the height 26 of the casing 12.1 n the illustrated embodiment, the length 22 of the casing 12 is approximately five times greater than the height 26 of the casing 12, and approximately two times greater than the width 24 of the casing 12. It will be understood that, for a given enclosure area, such an elongate casing 12 provides a larger internal surface 16 for transfer of heat from the high voltage busbars 102 to the casing cooling arrangement 40 than in less elongate alternatives. In some embodiments, the length 22 of the casing 12 is in a range of about 600 mm to about 1200 mm. In some embodiments, the width 24 of the casing 12 is in a range of about 100 mm to about 200 mm. In some embodiments, the height 26 of the casing 12 is in a range of about 80 mm to about 150 mm. The cooling channels 42 have a length 60 (illustrated in Figure 4), a width 62 (illustrated in Figure 3) and a depth 64 (illustrated in Figure 3). In the embodiment of Figures 3 and 4, the cooling channels 42 are elongate. In other words, the length 60 of the cooling channels 42 is greater than the width 62 and / or the depth 64 of the cooling channels 42. In embodiments where there is a plurality of cooling channels 42, the width 62 of the cooling channels 42 may be the collective width of the cooling channels 42 (e.g., including any channel walls 68 between cooling channels 42). In the illustrated embodiment, the length 60 of the cooling channels 42 extends along the majority of the length 22 of the casing 12 (e.g., at least 70% of the length 22 of thecasing 12, e.g. at least 80%, e.g. at least 90%). In this way, cooling is provided along the majority of the length 22 of the casing 12. In some embodiments, the length 60 of the cooling channels 42 is in a range of about 50 mm to about 1100 mm. In some embodiments, the width 62 of the cooling channels 42 is in a range of about 10 mm to about 150 mm. In some embodiments, the depth 64 of the cooling channels 42 is in a range of about 3 mm to about 12 mm. In the embodiment of Figures 3 and 4, the casing 12 has a base portion 28 for mounting the one or more electronic components of the battery electronics module 100 (e.g., defining the internal surface 16 of the casing 12). The casing 12 also has a cover portion 30 coupled to the base portion 28. The enclosure 14 is defined between the base portion 28 and the cover portion 30. Such a structure simplifies manufacturing. For example, electronic components may be mounted on the base portion 28, and then the cover portion 30 may be placed over the electronic components once assembled. In some embodiments, the cover portion 30 is releasably coupled to the base portion 28 (e.g. via one or more releasable fasteners such as bolts, or via one or more clips or snap-fit elements). This simplifies maintenance / repair (e.g., by releasing the cover portion 30 to access the electronic components inside the enclosure 14). In the illustrated embodiment, the casing cooling arrangement 40 is configured to cool the base portion 28 (i.e., the portion on which the electronic components are mounted). This improves cooling performance compared to having cooling on the cover portion 30. In other embodiments, the casing cooling arrangement 40 is configured to cool the cover portion 30 (e.g., instead or in addition to the base portion 28). In some embodiments, the casing 12 has athermal conductivity of at least 100 W / mK, e.g., at least 150 W / mK, e.g., at least 200 W / mK. This facilitates good heat transfer from the high voltage busbars 102 mounted adjacent to the internal surface 16 of the casing 12 to the cooling fluid flowing within the cooling channels 42. In some embodiments, the casing 12 is formed of a metallic material. Metallic material provides good structural integrity as well as good thermal conductivity. In addition, metallic material may be easily cast to the required shape. In some embodiments, the casing 12 is formed of an aluminium alloy material. Aluminium alloy material offers a particularly good tradeoff between cost, structural integrity, thermal conductivity and weight. In some embodiments, the casing 12 is formed as a cast metal body (e.g., a cast aluminium alloy body). In other embodiments, the casing 12 is forged or produced via additive manufacturing. In the embodiment of Figures 3 and 4, a thermal interface material 106 is provided between the high voltage busbars 102 and the internal surface 16 of the casing 12. The thermal interface material 106 facilitates heat transfer from the high voltage busbars 102 to the cooling fluid flowing within the cooling channels 42. For example, the thermal interface material 106 may have a thermal conductivity of at least 0.5 W / mK, e.g., at least 1 W / mK, e.g., at least 2 W / mK, e.g., at least 3 W / mK, e.g., at least 4 W / mK, e.g., at least 5 W / mK, e.g., at least 6 W / mK, e.g., at least 7 W / mK, e.g., at least 8 W / mK, e.g., at least 9 W / mK, e.g., at least 10 W / mK. The thermal interface material 106 may be electrically insulating. In this way, the thermal interface material 106 inhibits conduction of electricity from the high voltage busbars 102 to the casing 12. It will be understood that, where the thermal interface material 106 is both electrically insulating and thermally conducting, the thermal interface material 106 provides two separate functions of facilitating heat transfer to the casing cooling arrangement 40 and inhibiting conduction of electricity to the casing 12. In some embodiments, the thermal interface material 106 has a volume resistivity volume resistivity of at least 109Q.cm, e.g., at least 1010Q.cm, e.g., at least 1011Q.cm, e.g., at least 1012Q.cm, e.g., at least 1013Q.cm. In some embodiments, the thermal interface material has a breakdown voltage of at least 1 Kv / mm, e.g., at least 2 Kv / mm, e.g., at least 3 Kv / mm, e.g., at least 4 Kv / mm, e.g., at least 5 Kv / mm, e.g., at least 6 Kv / mm. In some embodiments, the thermal interface material 106 is a ceramic filled silicone material. For example, the material known as “TP-300” may be used as a suitable thermal interface material 106. Such materials provide a good combination of thermal conductivity and electrical insulation. In some embodiments, the thermal interface material 106 has a thickness in a range of about 0.5mm to about 10mm. Such a thickness may provide a good tradeoff between having adequate electrical insulation as well as good thermal conductivity. In the embodiment of Figures 3 and 4, the thermal interface material 106 is a single sheet of material which extends under the plurality of high voltage busbars 102. However, in other embodiments the thermal interface material 106 may be provided as separate strips of material which track the profile of the high voltage busbars 102. For example, such a configuration is illustrated in the alternative embodiment of Figure 6. In the embodiment of Figures 3 and 4, an electrical insulation material 108 is provided between the high voltage busbars 102 and the internal surface 16 of the casing 12. In particular, the electrical insulation material 108 is provided between the thermal interface material 106 and the internal surface 16 of the casing 12.The electrical insulation material provides backup insulation protection (i.e., double protection) in the event of any issues with the electrical insulation of the thermal interface material 106. In some embodiments, the electrical insulation material 108 is an electrical tape material. The electrical tape material may have an acrylic adhesive. In some embodiments, the electrical insulation material 108 is a polyimide film material. Although the thermal interface material 106 and the electrical insulation material 108 are shown as approximately equal thickness in Figures 3 and 4, it will be understood that the thickness of the electrical insulation material 108 may be much smaller than the thickness of the thermal insulation material 106. For example, the electrical insulation material 108 may have a thickness in a range of about 0.01 mm to 0.2 mm, e.g., in a range of about 0.03 mm to 0.1 mm, e.g., in a range of about 0.05 mm to 0.09 mm. In some embodiments, the electrical insulation material has an insulation resistance of at least 103 MQ, e.g., at least 104 MQ, e.g., at least 105 MQ, e.g., at least 106 MQ. I n the embodiment of Figures 3 and 4, the electrical insulation material 108 is a single sheet of material. I n other embodiments, the electrical insulation material 108 may be provided in discrete strips in a similar manner to the thermal interface material 106 of Figure 6. In the embodiment of Figures 3 and 4, the battery electronics module 100 has an internal cover 110 configured to isolate the high voltage busbars 102 mounted adjacent to the internal surface 16 of the casing 12 from one or more additional electronic components 112 provided inside the enclosure 14 above the high voltage busbars 102. Such an internal cover 110 allows the high voltage busbars 102 to be mounted underneath other components (improving cooling of the high voltage busbars 102), whilst making use of space within the enclosure 14 above the high voltage busbars 102. In the illustrated embodiment the internal cover 110 is configured to isolate the high voltage busbars 102 from a battery electronics control module 112. The battery electronics control module 112 may have one or more processors for controlling operation of the battery electronics module 100. In some embodiments, the internal cover 110 is configured to urge the high voltage busbars 102 towards the internal surface 16 of the casing 12. This improves heat transfer (e.g., by compressing the thermal interface material 106 positioned between the high voltage busbars 102 and the internal surface 16). In some embodiments, the internal cover 110 is electrically insulating. This inhibits malfunction to the battery electronics control module 112 mounted above the internal cover 110, by inhibiting unwanted conduction of electricity from the high voltage busbars 102. In some embodiments, the internal cover 110 comprises a thermal interface material. This may facilitate transfer of heat from the battery electronics control module 112 to the casing 12 and thus to the cooling fluid flowing through the cooling channels 42.1 n such embodiments, the thermal interface material may be electrically insulating as well as thermally conductive (e.g., of a similar material to the thermal interface material 106 described above). In some embodiments, the internal cover 110 is made of plastics material. Referring now to Figures 5 and 6, a battery electronics module 100 according to a further embodiment is illustrated. Common features between the battery electronics modules 100 of Figures 3 and 4 and Figures 5 and 6 are given the same reference numerals, and only differences are discussed in detail. As in the embodiment of Figures 3 and 4, the casing cooling arrangement 40 of Figure 5 includes: a plurality of cooling channels 42, 42B; a common casing inlet 56 for inflow of cooling fluid to the plurality of cooling channels 42, 42B; and a common casing outlet 58 for outflow of cooling fluid from the plurality of cooling channels 42, 42B. In Figure 5, the covering 44 has been omitted to show the internal structure of the cooling channels 42, 42B. However, it will be understood that a covering 44 similar to that of Figures 3 and 4 would be provided in the assembled battery electronics module 100. In the embodiment of Figure 5, some of the cooling channels 42 merge together at a confluence region 66, so that the number of cooling channels 42 varies along the length 22 of the casing 12. This may facilitate improved cooling by having more cooling channels 42 at hot spots which generate more heat, and better structural integrity by having fewer cooling channels 42 at colder regions of the casing 12. As can be seen in Figure 5, the cooling channels 42 define parallel paths which converge at the confluence regions 66. In the embodiment of Figure 5, there are multiple confluence regions 66 such that the number of cooling channels 42 changes more than once along the length of the casing 12. In particular, at a first end 32 of the casing 12 (proximal to the casing inlet 56), there are five separate cooling channels 42 which merge via three confluence regions 66 into two separate cooling channels 42 in the middle of the casing 12. These cooling channels 42 then merge into a single cooling channel 42 towards a second end 34 of the casing 12 (distal the casing inlet 56). In the embodiment of Figure 5, the casing inlet 56 is provided at the first end 32 of the casing 12. Instead of the casing outlet 58 being provided at the second end 34 of the casing 12, it is provided in a side of the casing 12 between the first and second ends 32, 34. In the illustrated embodiment, there is a downstream cooling channel 42B which is connected in series to the other cooling channels 42 (which may be considered as upstream cooling channels 42). The upstream cooling channels 42 extend from the first end 32 to the second end 34 of the casing. The outlet cooling channel 42B extends from the second end 34 of the casing 12 to the casing outlet 58. As will be described in more detail below, the upstream cooling channels 42 may be connected to the downstream cooling channel 42B via an internal cooling arrangement 80. At portions along the length 22 of the casing 12 where there are multiple cooling channels 42, 42B each cooling channel 42, 42B is separated from adjacent cooling channels 42, 42B by a channel wall 68. In the embodiment of Figure 5, the channel walls 68 which separate the parallel paths in the upstream cooling channels 42 each have a bulbous end 70 at the respective confluence region 66. This may facilitate mixing of cooling fluid at the confluence region 66. In the embodiment of Figure 5, the cooling channels 42, 42B are configured to direct cooling fluid along the length 22 of the casing 12. The width 62 of the cooling channels 42, 42B (i.e., the collective width of all of the cooling channels 42, 42B) varies along the length 22 of the casing 12. This may facilitate improved cooling by having a greater width 62 at hot spots which generate more heat, and better structural integrity by having a narrower width 62 at colder regions of the casing 12.1 n the illustrated embodiment, at portions of the casing 12 where the width 62 of the cooling channels 42, 42B is increased, the number of cooling channels 42, 42B is greater. For example, as mentioned above, there are five separate cooling channels 42 proximal to the first end 32 of the casing 12, and this corresponds to the widest portion of the cooling channels 42, 42B. Similarly, there are only two cooling channels 42, 42B towards the second end 34 of the casing 12, and this corresponds to a narrower portion of the cooling channels 42, 42B. In some embodiments, the casing cooling arrangement 40 is configured to provide a higher rate of cooling in the casing 12 proximal to the high voltage busbars 102 and associated electrical contacts 104 than at other portions of the casing 12. For example, the wider region of the cooling channels 42 towards the first end 32 of the casing 12 may correspond to a region with a high density of high voltage busbars 102, electrical contacts 104 and / or other heat generating components. In the embodiment of Figure 5, two high voltage connectors 124 are provided in the external surface 18 of the casing 12. This facilitates connection of the electronic components inside the enclosure 14 to the battery 202 and electrical consumers of the vehicle 200 (e.g., electric motors, heaters, etc.). The battery electronics module 100 may include (or be connected to) a cooling fluid source 114 in fluid communication with the casing cooling arrangement 40. For example, Figure 7 illustrates an arrangement with a cooling fluid reservoir 116 and a pump 118 configured to circulate cooling fluid from the cooling fluid reservoir 116 through the casing cooling arrangement 40. In more detail, the pump 118 is provided in a cooling fluid supply line 120 which runs between the cooling fluid reservoir 116 and the casing inlet 56. The casing outlet 58 is coupled to the cooling fluid reservoir 116 by a cooling fluid return line 122. I n this way, cooling fluid can be driven by the pump 118 along a cooling flow path 90 which runs: from the cooling fluid reservoir 116 along the cooling fluid supply line 120 to the casing inlet 56; from the casing inlet 56 through one or more cooling channels 42, 42B of the casing cooling arrangement 40 to the casing outlet 58; and from the casing outlet 58 along the cooling fluid return line 122 to the cooling fluid reservoir 116. In the embodiment of Figure 7, the cooling flow path 90 also runs through an internal cooling arrangement 80 within the enclosure 14. The internal cooling arrangement 80 has an internal cooling inlet 82, an internal cooling outlet 84, and an internal cooling flow path 86 which runs within the enclosure 14 between the internal cooling inlet 82 and the internal cooling outlet 84. The internal cooling flow path 86 may be defined by one or more pipes or other conduits. Having such an internal cooling arrangement 80 provided within the enclosure 14 may allow higher level of cooling for particular dedicated components inside the enclosure 14. In the embodiment of Figure 7, the casing cooling arrangement 40 is in fluid communication with the internal cooling arrangement 80. In other words, the casing cooling arrangement is connected to the internal cooling inlet 82 and the internal cooling outlet 84 (e.g., in series as part of the same cooling flow path 90). This may simplify cooling fluid connections in comparison to alternatives where the casing cooling arrangement 40 and internal cooling arrangement 80 are separate from each other (e.g., connected to the cooling fluid source 114 in parallel). Although not visible from the underside view of Figure 5, the battery electronics module 110 has an internal cooling arrangement 80 similar to that illustrated in Figure 7. In particular, there is an internal cooling inlet 82 and internal cooling outlet 84 which connect the upstream and downstream cooling channels 42, 42B to an internal cooling flow path (not shown). In the embodiment of Figure 5, the internal cooling inlet 82 and internal cooling outlet 84 are provided at the second end 34 of the casing 12 (i.e., distal the casing cooling inlet 56). In this way, cooling fluid flows along the length 22 of the casing 12 to cool the casing 12 and high voltage busbars 102 mounted adjacent thereto, before entering the internal cooling arrangement 80. It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present 5 application. For example, the one or more cooling channels 42 may be defined by one or more cooling pipes positioned proximal to the external surface 18 of the casing 12 (i.e., instead of being provided in the casing 12); it will be understood that more electronic components may be provided within the enclosure 14 than in the illustrated figures, for example, high voltage busbars 102, electrical contacts 104, battery electronics control modules 112, AC / DC converters, DC / AC converters, charge modules, etc.; the electronic components mounted adjacent to the internal surface 16 of the casing 12 for cooling via the casing cooling arrangement 40 may include other types of electronic components (e.g., in addition to or instead of 10 the high voltage busbars 102 and associated electrical contacts 104); the number and shape of the cooling channels 42, 42B may differ from that shown in the illustrated embodiments; the casing 12 may have a different shape to the elongate casings 12 shown in the illustrated embodiments; the internal cooling arrangement 80 may be omitted from the embodiments of Figures 5 and 7; the embodiment of Figure 5 may include a cooling channel 42 which varies in width, instead of multiple cooling channels 42 which converge at a confluence region 66. 15 It should also be noted that whilst the appended claims set out particular combinations of features described above, the scope of the present disclosure is not limited to the particular combinations hereafter claimed, but instead extends to encompass any combination of features herein disclosed.

Claims

1. A battery electronics module for a vehicle, the battery electronics module comprising:a casing which defines an enclosure for one or more electronic components;one or more high voltage busbars mounted inside the enclosure adjacent to an internal surface of the casing; anda casing cooling arrangement provided outside the enclosure, the casing cooling arrangement comprising one or more cooling channels which are substantially aligned with the one or more high voltage busbars, wherein the casing cooling arrangement is configured to receive a flow of cooling fluid through the one or more cooling channels for cooling the casing and thereby cooling the one or more high voltage busbars.

2. The battery electronics module of claim 1, wherein the one or more cooling channels are provided in the casing.

3. The battery electronics module of claim 2, wherein the one or more cooling channels are provided in an external surface of the casing, and wherein the battery electronics module further comprises a covering coupled to the external surface of the casing to cover the one or more cooling channels.

4. The battery electronics module of claim 3, wherein the covering is welded to the external surface of the casing; optionally via friction stir welding.

5. The battery electronics module of claim 3 or 4, wherein the covering comprises an inner side adjacent the one or more cooling channels andan outer side, the outer side having one or more fins, ridges or other structures to increase the surface area of the outer side of the covering.

6. The battery electronics module of any preceding claim, wherein the casing cooling arrangement comprises a plurality of cooling channels.

7. The battery electronics module of claim 6, wherein the casing cooling arrangement comprises a common inlet for inflow of cooling fluid tothe plurality of cooling channels and / or a common outlet for outflow of cooling fluid from the plurality of cooling channels.

8. The battery electronics module of any preceding claim, wherein the one or more cooling channels are configured to direct cooling fluid along a length of the casing, and wherein a width of the one or more cooling channels varies along the length of the casing.

9. The battery electronics module of any preceding claim, wherein the casing has a thermal conductivity of at least 100 W / mK, optionally at least 150 W / mK, optionally at least 200 W / mK.

10. The battery electronics module of any preceding claim, wherein the casing is formed of a metallic material; optionally an aluminium alloy material.

11. The battery electronics module of any preceding claim, further comprising a thermal interface material provided between the one or more high voltage busbars and the internal surface of the casing; optionally, wherein the thermal interface material has a thermal conductivity of at least 0.5 W / mK, and wherein the thermal interface material is electrically insulating.

12. The battery electronics module of any preceding claim, further comprising an electrical insulation material provided between the one or more high voltage busbars and the internal surface of the casing; optionally, provided between a thermal interface material and the internal surface of the casing.

13. The battery electronics module of any preceding claim, further comprising an internal cover configured to isolate the high voltage busbars mounted adjacent to the internal surface of the casing from one or more additional electronic components provided inside the enclosure above the one or more high voltage busbars.

14. A battery electronics module housing apparatus comprising:a casing which defines an enclosure for one or more electronic components, wherein the casing comprises an internal surface for mounting the one or more electronic components within the enclosure; and5 a casing cooling arrangement provided outside the enclosure, the casing cooling arrangement comprising one or more cooling channels,wherein the casing cooling arrangement is configured to receive a flow of cooling fluid through the one or more cooling channels for cooling the casing and thereby cooling the one or more electronic components;wherein the one or more cooling channels are provided in an external surface of the casing, and wherein the battery electronics module housing apparatus further comprises a covering coupled to the external surface of the casing to cover the one or more cooling channels.1015. A vehicle comprising the battery electronics module of any of claims 1 to 13 and / or the battery electronics module housing apparatus of claim14.15Application No: GB2415816.4Claims searched: 1-13, and 15 in partExaminer: Jack EvansDate of search: 8 April 2025Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance X 1-9,11, 12, 15 CN 220140050 U (HUIZHOU EVE ENERGY CO LTD), see Figures 2 and 5 and associated description. X 1-5, 7-10, 13, 15 CN 219226420 U (SHANGRAO LUOXIN INTELLIGENT TECH CO LTD), see Figures 1 and 4 and associated description. X 1-9, 15 CN 218333983 U (CHUNENGNEW ENERGY CO LTD), see Figure 2 and associated description.Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if combined with one or more other documents of same category. P Document published on or after the declared priority date but before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:Search of GB, EP, WO &US patent documents classified in the following areas of the UKCX :Worldwide search of patent documents classified in the following areas of the IPC_____________B60L; HO IM; H05K____________________________________________The following online and other databases have been used in the preparation of this search report SEARCH-PATENTInternational Classification:Subclass Subgroup Valid From HO IM 0010 / 613 01 / 01 / 2014 HO IM 0010 / 625 01 / 01 / 2014 H05K 0007 / 20 01 / 01 / 2006Application No: GB2415816.4Claims searched: 14, and 15 in partExaminer: Jack EvansDate of search: 17 June 2025Patents Act 1977Further Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance X X X X X X 14, 15 14, 15 14, 15 14, 15 14, 15 14 CN 109936964 A (DEERE &CO), see Figure 1 and associated description. WO 2022 / 135169 Al (BYD CO LTD), see Figure 1 and associated description. US 2022 / 0399596 Al (SCHMITT et al.), see Figure 1 and paragraphs [0006], [0011], [0033] and [0037], CN 108110172 A (ZHUHAI GREE PREC MOLD CO LTD), see Figure 1 and associated description. CN 105514319 B (CONTEMPORARY AMPEREX TECHNOLOGY LTD), see Figure 5 and associated description. CN 221747340 U (YUANSU INDUSTRIAL TECH SUZHOU CO LTD), see Figure 2 and associated description.Categories: X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if combined with one or more other documents of same category. P Document published on or after the declared priority date but before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:Search of GB, EP, WO &US patent documents classified in the following areas of the UKCX :Worldwide search of patent documents classified in the following areas of the IPC_____________HO IM; H05K_______________________________________________The following online and other databases have been used in the preparation of this search report SEARCH-PATENTInternational Classification:Subclass Subgroup Valid From HO IM 0010 / 613 01 / 01 / 2014 HO IM 0010 / 625 01 / 01 / 2014 H05K 0007 / 20 01 / 01 / 2006

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