Battery assembly for a vehicle

Abstract

The present disclosure relates to a battery assembly for a vehicle such as an electric vehicle or a hybrid electric vehicle, and to methods associated with such an assembly. As disclosed, there is provided a support member for a fluid-cooled battery, said support member arranged for supporting battery cells, the support member comprising a generally planar wall, a rim extending at least partially around the wall and extending in a normal direction from a first side of the wall so as to at least partially bound a first area for containing a fluid, an inlet for admitting fluid into the first area, and one or more outlets for allowing fluid to outflow, wherein the first area is divided into at least a first chamber and a second chamber, each chamber arranged for housing at least a part of each cell of a respective plurality of cells, wherein the inlet is arranged in fluid communication with the first chamber, the second chamber is in fluid communication with the one or more outlets, and wherein a respective divider between each successive pair of chambers comprises a plurality of channels for fluid communication therebetween. The disclosed battery assembly provides improved battery performance by virtue of improved cell temperature management, particularly when packaging is constrained.

Description

[0001] BATTERY ASSEMBLY FOR A VEHICLE

[0002] Field

[0003] The present disclosure relates to a battery assembly for a vehicle such as an electric vehicle or a hybrid electric vehicle, components thereof, and to methods associated with such an assembly.

[0004] Background

[0005] In an electric vehicle (e.g. a fully electric or hybrid electric vehicle, either plug-in or non-plug-in), performance (in terms of acceleration, top speed and range) is to a significant extent determined by the storage capacity, peak / sustained current delivery capacity, and charge / discharge cycle efficiency of the vehicle’s battery pack (or “battery assembly”). The battery pack may be constructed from a plurality of individual battery cells, connected in parallel or series, or a combination thereof. The above-mentioned performance factors are in turn dependent to an extent upon the operating temperatures of the cells which make up the battery pack, therefore it is desirable to effectively control the operating temperature of the cells. Constraints on the available space in a vehicle for locating a battery pack can make it challenging to design a battery pack that achieves said requirement to effectively control the operating temperature of the cells. The present disclosure aims to alleviate, at least to an extent, problems associated with existing vehicle battery pack assemblies.

[0006] Summary

[0007] According to a first aspect of the present disclosure there is provided a support member for a fluid-cooled battery, said support member arranged for supporting battery cells, the support member comprising: a generally planar wall; a rim extending at least partially around the wall and extending in a normal direction from a first side of the wall so as to at least partially bound a first area for containing a fluid; an inlet for admitting fluid into the first area; and one or more outlets for allowing fluid to outflow; wherein the first area is divided into at least a first chamber and a second chamber, each chamber arranged for housing at least a part of each cell of a respective plurality of cells, wherein the inlet is arranged in fluid communication with the first chamber, the second chamber is in fluid communication with the one or more outlets, and wherein a respective divider between each successive pair of chambers comprises a plurality of channels for fluid communication therebetween.

[0008] Optionally, the inlet is in direct fluid communication with the first chamber.

[0009] Optionally, at least a portion of the first chamber is located proximate to the inlet and at least a portion of the second chamber is located distal from the inlet.

[0010] Optionally, the inlet and at least a portion of the first chamber is located at a region of the support member that is intended to be uppermost when in use, and at least a portion of the second chamber is located at a region of the support member that is intended to be lowermost in use.

[0011] Optionally, the support member further comprises one or more additional chambers interposed between the first and second chambers on the first side.

[0012] Optionally, each divider is arranged generally perpendicular to a mean direction of fluid flow from the first chamber to the second chamber.

[0013] Optionally, the channels are substantially evenly spaced along the divider in a direction that is perpendicular to the mean direction of fluid flow from the first chamber to the second chamber.

[0014] Optionally, each channel is aligned with a cell position, and optionally wherein the number of channels is equal to the number of cells along the length of the respective divider.

[0015] Optionally, the wall is arranged for supporting the cells, and optionally wherein the wall further comprises a plurality of openings, each opening provided for receiving and supporting a respective cell, and optionally wherein the diameter of each opening is matched to the diameter of the cells so as to prevent leakage through an opening when a cell is present in an opening.

[0016] Optionally, the rim also extends in an opposite normal direction from a second side of the wall so as to at least partially bound a second area for containing fluid. Optionally, the second area comprises at least a third chamber, wherein at least a portion of the third chamber is located adjacent the second chamber. Optionally, the wall portion comprises a plurality of orifices in a region distal from the inlet such that the second chamber is in fluid communication with the third chamber, and optionally wherein the orifices are provided at positions between cells, and optionally wherein the number of orifices is equal to the number of cells minus one, counted along the length of a divider. Optionally, the second area is also divided into at least the third chamber and a fourth chamber, each of those chambers arranged for housing at least a part of each cell of a respective plurality of cells, wherein the fourth chamber is in direct fluid communication with the one or more outlets, and wherein fluid communication is provided for between the third chamber and the fourth chamber.

[0017] Optionally, the first chamber further comprises a space for receiving fluid from the inlet, the space arranged for facilitating fluid flow in a crosswise direction that is substantially parallel to the wall and perpendicular to the mean direction of fluid flow from the first chamber to the second chamber, and the space having a cross-section that is arranged for balancing respective flows of fluid between respective cells from the space in the first chamber towards the second chamber via the plurality of channels, and optionally wherein the cross-section varies along the crosswise direction.

[0018] Optionally, the inlet comprises a tubular inlet hole through the wall of the support member, and the support member further comprises an inlet passage connecting the inlet hole to the first chamber. Optionally, the inlet hole is provided in the support member at a position adjacent to the first chamber such that a resulting angle, at which the inlet passage leads from the inlet hole to the space of the first chamber, is optimised to equalise respective flows of fluid passing between respective cells in the first chamber, thereby aiding equalisation of respective flows of fluid passing through each respective one of the plurality of channels.

[0019] Optionally, the support member comprises two adjacent halves, each half comprising any of the preceding the features. Optionally, both halves share a common inlet wherein an axis of symmetry passes through a centre of the common inlet, which axis lies in the plane of the wall and is generally parallel to the mean direction of fluid flow from the first chamber to the second chamber, wherein each half is mirrored with respect to the other half about the axis of symmetry or each half is rotationally symmetric about the axis of symmetry. Optionally, in use the fluid flows in a first mean direction from the first chamber to the second chamber, then through the wall from the second chamber to the third chamber, and then in a second mean direction from the third chamber to the one or more outlets, wherein the second mean direction is substantially opposite to the first mean direction.

[0020] According to a second aspect of the present disclosure there is provided a subassembly comprising a support member of the first aspect, a dividing plate joined to at least one major side of the support member, and a gasket provided at the dividing plate to seal around the periphery of a cell located through an opening in the dividing plate.

[0021] According to a third aspect of the present disclosure there is provided an assembly comprising a plurality of the support members of the first aspect. Optionally, the assembly further comprises respective dividing plates interposed between adjacent support members, each dividing plate for inhibiting fluid flow between chambers of adjacent support members, and optionally wherein each dividing plate is joined to a side of a respective support member. Optionally, one or more of the dividing plates comprises respective openings corresponding to at least some of the openings in the walls of each of the support members, and optionally wherein the respective openings correspond to at least the inlet opening and / or the openings for supporting the cells. Optionally, the assembly further comprises respective gaskets interposed between adjacent support members, each gasket provided at the dividing plate to seal around the periphery of a cell located through an opening in the dividing plate.

[0022] Optionally, the tubular inlet holes of each of the support members of the assembly are aligned with each other so as to form an integral inlet gallery, and optionally wherein the assembly comprises, at an end, an end plate comprising a coolant feed passage for supplying coolant to the inlet gallery.

[0023] According to a fourth aspect of the present disclosure there is provided a method of producing a battery for a vehicle, comprising assembling a plurality of the support members of the first aspect into an assembly according to the third aspect.

[0024] According to a fifth aspect of the present disclosure there is provided a battery assembly for a vehicle, comprising: a housing, for containing a coolant fluid and at least one battery cell to be cooled by said coolant fluid; and the assembly of the third aspect.

[0025] Optionally, the housing contains at least one battery cell.

[0026] Optionally, the battery assembly further comprises: one or more pressure or temperature sensors; and a monitoring device that monitors said sensors to determine based upon their outputs whether or not a cell thermal event has occurred, and upon such determination trigger a warning to a vehicle occupant.

[0027] Optionally, the housing is completely filled or substantially completely filled with coolant fluid surrounding at least one battery cell, and preferably wherein the coolant fluid is a dielectric oil.

[0028] Optionally, the housing has an opening therein for fluid connection with a pump to enable coolant fluid to be circulated around the at least one battery cell, and optionally arranged such that when in operation with said pump, fluid that has been heated by one or more battery cells is withdrawn from the housing and is returned to the array of cells after having been cooled by passing through a cooler unit.

[0029] Optionally, the housing has a first horizontal dimension that is transverse when mounted in a vehicle, and which is greater than a second horizontal dimension that is orthogonal to the first horizontal dimension, wherein a plurality of the support members of the first aspect are stacked in parallel along a direction of the first horizontal dimension.

[0030] Optionally, the battery assembly further comprises a mounting portion extending forwards from a central portion of the housing, for mounting components associated with the battery assembly including at least one of a coolant pump, a coolant filter, a heat exchanger for cooling coolant fluid, a fuse, a manual switch, a high voltage contactor, a gas venting port, a high voltage connector, and an electrical disconnection point.

[0031] Optionally, the battery assembly further comprises an attached enclosure for enclosing electronic components that are associated with the battery pack including at least one of a high voltage electronic component, a fuse, a high voltage contactor, a current sensor, a high voltage connector, and an electrical disconnection point, wherein the enclosure is sealed from the interior of the housing.

[0032] According to a sixth aspect of the present disclosure there is provided a motor vehicle including apparatus as defined in any of the first, second, third and fifth aspects.

[0033] It will be appreciated in the light of the present disclosure that certain features of certain aspects and / or embodiments described herein can be advantageously combined with those of other aspects and / or embodiments. The following description of specific embodiments should not therefore be interpreted as indicating that all of the described steps and / or features are essential. Instead, it will be understood that certain steps and / or features are optional by virtue of their function or purpose, even where those steps or features are not explicitly described as being optional. The above aspects are thus not intended to limit the scope of the present invention which is instead defined by the appended claims.

[0034] Description of Figures

[0035] Aspects of the disclosure may be carried out in various ways and some preferred embodiments will now be described by way of example only and in a non-limiting way with reference to the accompanying drawings, in which:

[0036] Figure 1 is a perspective view of a support member for a fluid-cooled battery for a vehicle, according to a described embodiment.

[0037] Figure 2 is a 2-dimensional view of the support member of Figure 1. Figure 3 is an enlarged view of chambers and interconnecting coolant channels of the left-hand half of the support member shown in Figures 1 and 2.

[0038] Figure 4a is a sectional perspective view of a battery assembly comprising a plurality of the support members of Figures 1-3 stacked together, wherein each of the comprised support frames has been sectioned through a vertical centreline so as to expose the integrated inlet gallery (top) which is formed from the upper-central tubular inlet hole of each support frame when stacked together.

[0039] Figure 4b is a non-sectioned view of an end of the assembly of Figure 4a, showing a coolant inlet duct formed in an end plate of the assembly.

[0040] Figure 4c is a perspective view of an example sub-assembly suitable for stacking in the assembly of Figure 4a, the sub-assembly comprising the support member of Figures 1-3, which is joined to a divider plate on one major side of the support member, wherein the other major side of the support has a gasket provided on it for sealing around the rim of the support and / or for sealing around the periphery of cells.

[0041] Figure 5 is a perspective view of a battery housing suitable for housing a battery assembly according to Figures 4a and 4b, and also showing a forward mounting portion on which ancillary components such as pump, filter and / or air-to-liquid cooler can be mounted in a transmission tunnel area of a vehicle.

[0042] Figure 6 is a side view of a battery housing such as that shown in Figure 5, when installed behind a seating area of the vehicle and in front of a vehicle’s rear wheels (not shown).

[0043] Figure 7 is a perspective view of a battery housing such as that shown in Figure 5, when installed in front of a vehicle’s rear wheels and behind a seating area of the vehicle.

[0044] Figure 8 is an electrical schematic diagram of a battery assembly according to an embodiment.

[0045] Detailed Description

[0046] Existing high voltage battery packs for electric / hybrid vehicles have been liquid cooled. In such existing battery packs, coolant flow and / or coolant temperature around certain cells in the pack has been uneven compared with that around certain other cells, leading to some battery cells receiving less cooling (and therefore operating at higher temperatures) than other battery cells.

[0047] Given that for series-connected cells (or modules further comprising multiple series or parallel-connected cells), the same current flows through each cell or module, it follows that if any of those cells or modules experiences an overheated condition (or reaches its maximum allowable operating temperature) then the current through it and through all other series-connected cells or modules must also be reduced until the overheated condition has ended. This effectively means that if any cell overheats or reaches a limiting temperature then the entire battery pack’s power rating must be temporarily reduced (in other words, the battery pack must be “de-rated”), which can seriously reduce vehicle performance.

[0048] Some previous designs have simply accepted that such “de-rating” conditions will occur from time to time, and accordingly they have designed spare capacity into their battery packs. Thus, the size and weight of some existing battery packs has been increased, to permit a certain amount of de-rating for such battery packs, as required to avoid overheating of the hottest cells, and this has resulted in those battery packs being larger and heavier than would be ideal.

[0049] The presently disclosed high voltage battery pack overcomes, at least to an extent, these drawbacks in prior battery packs, by improving the balancing of coolant flow rate and / or coolant temperature, between the various coolant flow paths around the cells, and by reducing pressure drop across the coolant flow path (which improves coolant flow). This helps to ensure that all cells in the battery pack are substantially equally cooled, thereby reducing battery pack de-rating requirements which might otherwise result from unequally hot cells in operation, especially under heavy and / or sustained electrical loads, and / or under high ambient temperatures. As a result, the size and weight of a vehicle battery assembly can be reduced for a given vehicle performance specification.

[0050] Referring to Figures 1 to 3, a support member 100 for a fluid-cooled battery (suitable for use in an electric or hybrid vehicle) is arranged for supporting battery cells 130 (e.g. 21700-format cells), e.g. by virtue of comprising a generally-planar wall 102 with cell-support features such as openings 112 through the wall 102 for receiving and thereby supporting respective cells.

[0051] Extending around the wall 102 is provided a rim 103, which rim 103 extends in a normal direction from the wall 102 on a first side of the wall 102, so as to at least partially bound a first area 104 for containing a fluid coolant 120. For example, when a cover plate and / or gasket (not shown) is placed in contact with (or joined to, e.g. by bonding or ultrasonic welding) the rim 103 of the support member 100, and when battery cells 130 are fitted into the openings 112 (said cells 130 and openings 112 having similar diameters, matched such that the cells 130 are supported in said openings 112 and fluid leakage around the cells 130 through the openings 112 is substantially prevented - said leakage optionally being further reduced by the close fitting of an elastomeric gasket around each of the cells 130), the first area 104 can contain coolant fluid 120.

[0052] Incorporated into the support member 100 is an inlet 101 for admitting fluid into the first area 104, and the support member 100 also comprises one or more outlets 105 for allowing fluid to outflow from the support member 100 (e.g. out from the first area 104, potentially via intermediate areas or chambers).

[0053] The first area 104 is divided into at least first and second chambers 106, 107 by a divider 108. Each chamber 106, 107, is arranged for housing at least a part of each one of a respective plurality of cells 130. For example, as illustrated, each of the first and second chambers 106, 107 has openings 112 for a number of cells (in this example, 8 cells per chamber, although other numbers of cells per chamber can be provided), such that each cell can pass through and be supported by the wall 102, whereby one portion (such as an end, or a section along the cell’s length) of each cell 130 is housed in its associated chamber on the first side of the wall 102, while another portion of each cell 130 is housed on the other side of the wall 102. Preferably but optionally, as shown in Figures 1 and 4c, a gasket 205 made of an elastomeric material (such as rubber) or a soft plastics material is provided at the wall 102 to seal around the perimeter of each cell 130 when located in a respective opening 112. For example, a planar gasket 205 can be provided having holes corresponding to the openings 112 for allowing cells 130 to pass therethrough and to seal around said cells 130 so as to reduce fluid leakage. For example, said gasket 205 can be bonded to the wall 102, or alternatively the gasket can be in the form of separate o-rings located in or at the openings 112, or the gasket can be in the form of elastomeric (or relatively soft plastics) material provided in or at the openings, and / or the gasket material can optionally be integrally moulded with the support frame 100. Optionally, further such gaskets 205 can be provided between the support member 100 and a generally flat divider plate 201 (shown in Figures 4a to 4c and further described below with reference to those Figures) that can be assembled against one or both major (planar) sides of the present support member 100, wherein said gaskets 205 are arranged to seal around the perimeter of cells 130 as they pass through said divider plate 201. Optionally a perimeter of each gasket 205 can be arranged to seal between the rim 103 and said divider plate 201, or alternatively said rim 103 can be joined to said divider plate 201 e.g. by adhesive bonding or by ultrasonic welding.

[0054] The inlet 101 is arranged in fluid communication with the first chamber 106 such that coolant fluid 120 can flow from the inlet 101 into the first chamber 106. For example, the inlet 101 can be directly connected to the first chamber 106, or the inlet 101 can be connected via a pipe or channel or part having a similar function, or via an intermediate chamber or fluid-containing area. The first chamber 106 is arranged in fluid communication with the second chamber 107 by virtue of a plurality of channels 109 in the divider 108 which provide for coolant fluid 120 to pass from the first chamber 106 into the second chamber 107. The second chamber 107 is arranged in fluid communication with the one or more outlets 105, either directly, or via further fluid-containing areas or chambers interposed between the second chamber 107 and the one or more outlets 105. In an example, such as that pictured in Figures 1 to 3, the first chamber 106, or at least a portion thereof, is located proximate to the inlet 101, and at least a portion of the second chamber 107 is located relatively distal from the inlet 101. By way of a specific example, the inlet 101 and first chamber 106 can be located at a location that is intended to be uppermost in use, and the second chamber 107 can be located at a location that is intended to be lowermost in use. Alternatively, a contrary arrangement can be employed, the choice being made based upon the relative merits in terms of efficiency benefits resulting from convection currents, and / or in terms of ease of flushing and / or bleeding air bubbles from the system in use. By way of one non-limiting example, each channel 109 can be approximately 20mm2in cross-section.

[0055] Optionally, one or more additional chambers can be interposed between the first chamber 106 and the second chamber 107, each chamber separated from each successive chamber by a respective divider 108, each divider having a plurality of channels 109 for permitting coolant fluid 120 to flow from each chamber to the next chamber. For example, each divider can have the same number of channels, or each divider can have a different number of channels, but nevertheless at least one divider has a plurality of channels. As shown in Figure 3, a mean (or at least the average) direction 111 of fluid flow from the first chamber 106 to the second chamber 107 is illustrated by a corresponding arrow, and each divider 108 is arranged generally perpendicular to the mean direction 111 of fluid flow (and parallel to the wall 102). As shown in Figures 1-3, at least one (and preferably each) divider 108 comprises a plurality of channels 109. Preferably, the channels 109 are evenly-spaced along each divider 108 in a direction that is perpendicular to the mean direction 111 of fluid flow. Further preferably, the channels 109 coincide with (e.g. are aligned with) cell positions (or with a multiple of cell positions), in which case it is convenient for the number of channels to be equal with the number of cells (or a multiple thereof, counted along the length of the divider 108). Alternatively, the channels 109 can be provided at positions between cells 130, in which case it is convenient for the number of channels 109 to equal the number of cells (or a multiple thereof, counted along the length of the divider) minus 1. Optionally, certain ones of the aforementioned channels 109 can be omitted, such as every other channel, or every third channel, every 4thchannel etc., provided that an evenly-spaced plurality of channels 109 is provided in said divider 108. By providing a plurality of channels 109 in said divider 108, evenly-spaced along the length of the divider 108 in a direction that is perpendicular to the mean direction 111 of fluid flow from first chamber 106 to second chamber 107, an advantageous result is that a plurality of parallel flow paths, each flowing generally parallel to each of the others, and each flowing parallel to the mean direction of flow 111, are encouraged when in use. Said parallel flow paths pass around the immersed cells 130 in use, and thereby provide more equal cooling (in terms of a comparison of how much cooling effect respective cells receive), by virtue of equalising flow rates / volumes around the respective cells 130. Previous approaches have employed different features which encourage a different flow path, such as a serpentine flow path, around cells, which has been found to be less effective in equalising flow rates / volumes around respective cells, compared to the presently described scheme.

[0056] Optionally in further embodiments, the rim 103 also extends in an opposite normal direction from a second side of the wall 102 so as to at least partly bound a second area 114 (in Figure 1 this second area is “behind” the first area, i.e. on an opposite side of the wall 102 from the first area 104, and is visible through the cell openings 112) for containing coolant fluid 120. Preferably, in a similar manner as the first area 104 comprises the first chamber 106 and second chamber 107, the second area 114 comprises at least a third chamber 116 which is located adjacent (on the other side of wall 102) to the second chamber 107. In such embodiments, the wall 102 comprises a plurality of orifices 118 between the first area 104 and the second area 114. Said orifices 118 can be separate holes provided in the wall 102, or can be provided in other forms such as e.g. by providing an enlarged opening 112 around certain ones of the cells 130. Any equivalent form which provides a path for coolant to pass through the wall can be employed in place of separate orifices 118. Thus, coolant fluid 120 can pass from the second chamber 107 towards the one or more outlets 105 via the second area 114. Preferably the orifices 118 are in a region distal from the inlet 101, such as in the second chamber 107 such that they open into the third chamber 116 and thus the second chamber 107 is in fluid communication with the third chamber 116. Optionally, the orifices 118 are provided at positions between cells 130, in which case optionally the number of orifices 118 is equal to the number of cells minus one (counted along the length of an associated divider 108), such that each pair of cells 130 has an orifice 118 therebetween. Alternatively, the orifices 118 can be provided in the form of enlarged openings around certain cells, said openings being in the wall 102 and / or in a gasket 205 provided at the wall 102, in which case optionally the number of orifices is equal to the number of cells (counted along the length of an associated divider). In other embodiments some orifices can be omitted, such as every other orifice 118 is omitted, or every second orifice 118 is omitted, etc.. By way of a non-limiting example, each orifice can be approximately 20mm2in cross-section. The inclusion of multiple channels 109 and / or multiple orifices 118 is also advantageous in that it reduces pressure drop across the overall coolant flow path, encouraging better coolant flow and reducing pumping energy requirements. In some embodiments, the third chamber 116 can occupy the whole of the second area 114 on the second side of the wall 102, however preferably, in a similar manner as the first area 104 comprises at least the first chamber 106 and second chamber 107, the second area 114 comprises at least the third chamber 116 and a fourth chamber 117, wherein the third chamber 116 is adjacent (on the other side of the wall 102) to the second chamber 107, and the fourth chamber 117 is adjacent (on the other side of the wall 102) to the first chamber 106. Similar to the first area 104, the chambers (e.g. third chamber and fourth chamber 116, 117) of the second area 114 each house at least a portion of each of a respective plurality of cells 130, and the chambers are divided from each other by respective dividers 108 which each comprise at least one but preferably a plurality of channels 109 so as to provide for fluid communication between the chambers (as described above for the first area 104, when multiple channels 109 are provided in the dividers 108, a plurality of generally parallel flow paths are encouraged, which enhances cooling equality). The fourth chamber 117 is arranged nearest the one or more outlets 105, and preferably the one or more outlets 105 are directly in a portion of the rim 103 associated with the fourth chamber 117, such that the fourth chamber 117 is in direct fluid communication with the one or more outlets 105. Preferably, the outlets 105 are in an upper portion of the rim 103 such that convection of the heated coolant fluid 120 assists with the exiting of the coolant fluid 120 from the outlets 105, e.g. into a housing 110 that contains a reservoir of coolant fluid 120. Further chambers can optionally be interposed between third and fourth chambers 116, 117 in the second area 114 on the second side of the wall 102, each chamber separated from the next chamber by a divider 108 as previously described.

[0057] Optionally, the first chamber 106 further comprises a space 119 near the inlet 101 and at a edge of the first chamber 106 that is furthest from the second chamber 107, said space 119 arranged for receiving coolant fluid 120 from the inlet 101 and facilitating fluid flow in a crosswise direction (parallel to the wall 102 and perpendicular to the mean direction 111 of fluid flow from the first chamber 106 to the second chamber 107), so as to facilitate spread of the incoming coolant in the crosswise direction across the space 119 at an entrance portion of the first chamber 106, thereby providing for relatively equalised flow of coolant 120 into each of the gaps between a first row of cells 130 (e.g. the uppermost row of cells in Figure 3, top-left row of cells in Figures 1 and 2) of the first chamber 106. In use, the aforementioned features having encouraged even distribution of coolant between the first row of cells 130 of the first chamber 106, it then follows that each of those resulting “part-flows” of coolant (between the first row of cells) have approximately the same flow rate and volume as each other. In operation, those “part-flows” then tend to continue in a separate, generally parallel, fashion towards the nearest corresponding channels 109 in the divider 108 that lies between the first chamber 106 and the subsequent chamber (e.g. the second chamber 107). Due to said generally parallel flow pattern, mixing between the “part-flows” is reduced or inhibited, which tends to ensure that flow rates / volumes remain balanced throughout the flow from inlet 101 to the one or more outlets 105 (rather than becoming substantially less equal further along the flow path). This tends to balance the cooling effect imparted to each of the cells 130. Preferably, the space 119 has a cross-section that is arranged so as to equalise the flow rate / volume of each of said part-flows, and optionally the space has a cross-section that varies along the crosswise direction so as to accomplish that aim. By way of one example, the distance from the rim 103 to cells 130 in the space 119 can be approximately 2mm. As described earlier, balancing the cooling applied to the cells is advantageous because it reduces the need to “de-rate” a battery pack incorporating such an arrangement, by virtue of reducing the likelihood of individual cells becoming overheated or reaching their maximum temperature.

[0058] Optionally, the inlet 101 comprises a tubular inlet hole through the wall 102 of the support member 100, as shown in Figures 1 to 3, and the inlet hole 101 is connected to the first chamber 106 by an inlet passage 113. Preferably, the inlet hole 101 is provided in the support member 100 at a position adjacent to the first chamber 106 such that a resulting angle at which the inlet passage 113 leads from the inlet hole 101 into the space 119 of the first chamber 106 is optimised to result in improved equalisation of the respective “part-flows” of coolant fluid 120 between respective cells 130 in the first chamber 106, thereby aiding equalisation of respective “part-flows” of coolant fluid 120 through the respective ones of the plurality of channels 109 in the divider 108 between the first chamber 106 and the next chamber (e.g. the second chamber 107).

[0059] Optionally, the support member comprises two halves 115, as shown in Figures 1 and 2 (either side of dividing line 135), each half comprising similar features as described above. In such embodiments, preferably both halves 115 share a common inlet 101, as shown in Figures 1 and 2. This is advantageous in terms of packaging compactness and in terms of reduced numbers of components to be assembled, thereby reducing size and cost. As shown in Figures 1 and 2, in such embodiments an axis of symmetry 135 passes through a centre of the common inlet 101, which axis 135 lies in the plane of the wall 102 and is generally parallel to the mean direction 111 of fluid flow from the first chamber 106 to the second chamber 107. Each half 115 is symmetrical with the other half 115. For example, each half 115 can be a mirror of the other half 115, mirrored about the axis 135. Alternatively, as shown in Figures 1 and 2, each half 115 can have rotational symmetry (e.g. rotational symmetry of 2) with respect to the other half 115 about the axis 135. This symmetry permits sharing of the common inlet 101 and thus reduces size and assembly requirements. Other embodiments where the two halves do not necessarily lie in a common plane, but nevertheless meet along the axis so as to permit sharing of a common inlet 101, are also possible.

[0060] For example, as shown in Figures 1 and 2, the first half (shown on the left-hand side of Figures 1 and 2) has the first area 104 comprising first and second chambers 106, 107 facing the viewer, and the second area 114 is not shown because it is behind the wall 102. Correspondingly, in that example, the second half (shown on the right-hand side of Figures 1 and 2) has the second area 114 comprising third and fourth chambers 116, 117 shown facing the viewer, while the first area 104 of the second half is not shown because it is behind the wall 102. Thus, coolant enters both first and second halves from the inlet 101, while coolant exits the second area 104 of the first half at the rear (as pictured in figures 1 and 2, although other orientations are possible in use) of the support frame, and coolant exits the second area 104 of the second half at the front (via the one or more outlets 105 labelled in Figure 2). Optionally, an opposite arrangement can be used. The features illustrated on the right-hand side of Figure 2 are equally representative of the features hidden but nevertheless present (in a symmetrical arrangement) behind the wall 102 on the left-hand side. Equally, the features illustrated on the left-hand side of Figure 2 can be taken to be present (albeit in a symmetrical arrangement) on the right-hand side of Figure 2, albeit hidden behind the wall 102.

[0061] Advantageously, in certain embodiments as illustrated, in use, fluid flows in a first mean direction 131 from the first chamber 106 to the second chamber 107, then through the wall 102 from the second chamber 107 to the third chamber 116 via the orifices 118, and then in a second mean direction 132 from the third chamber 116 to the one or more outlets 105 (optionally via the above-described fourth chamber 117), wherein the second mean direction 132 is opposite to the first mean direction such that a “contra-flow” fluid path is provided. The “mean direction”, in this context, means the general, average or overall direction, i.e. what is illustrated by the arrows 111, 131, 132. This “contra-flow” arrangement is advantageous because in use, the cells 130 dissipate heat which passes by conduction into the coolant fluid 120 contacting the cells 130. Thus, the coolant fluid 120 warms up as it passes from the inlet 101 to the one or more outlets 105 via the first and second chambers 106, 107 and optionally also the third and fourth chambers 116, 117. Thus, the coolant fluid 120 in the first chamber 106 is cooler than the coolant fluid 120 in the second chamber 107, which is cooler than the coolant fluid 120 in the third chamber 116, which is in turn cooler than the coolant fluid 120 in the fourth chamber 117. However, since an average of the temperature of coolant in the first and fourth chambers is approximately equal to an average of the temperature of coolant in the second and third chambers 107, 116, it is provided that cells 130 straddling the first and fourth chambers 106, 117 via openings 112 receive approximately the same cooling effect as cells 130 which straddle the second and third chambers 107, 116. This advantageously further equalises the cooling effect provided to the respective cells of a battery pack employing an assembly of the above-described cell support members, and thus battery pack “derating” is further reduced, thereby battery packs can be smaller and cheaper for a given power rating requirement. Preferably the second mean direction is upwards in use, such that the fluid is travelling upwards when hottest, thereby benefiting from flow assistance by virtue of convection.

[0062] As shown in Figures 4a and 4b, an assembly 200 comprising a plurality of the above-described support members 100 can be provided by “stacking” a plurality of said support members 100 side-by-side such that their walls 102 are parallel and such that their rims 103 align to substantially seal coolant fluid 120 within the assembly 200. In such an assembly, one or more divider plates 201 can be interposed between successive support members 100, for example such that the third and fourth chambers 116, 117 of a first support member are separated from adjacent first and second chambers 106, 107 of an adjacent second support member, thereby preventing interference / leakage between flow paths of the first support member 100 and the second support member 100.

[0063] The respective inlet tubes 101 of each of the support members 100 (and also corresponding holes in the divider plates 201) align and combine so as to provide an inlet gallery 203 which is integrated into the assembly 200, and which reduces assembly requirements. Figure 4a shows a “stack” of a number of the support members 100 of Figures 1 and 2, comprised in a number of the sub-assemblies of Figure 4c, albeit only one half of those support members 100 are shown (the other half having been sectioned away through the dividing line 135, so as to permit the inlet gallery 203 to be viewed).

[0064] In an example embodiment as shown in Figure 4c, each support member 100 has a divider plate 201 joined to at least one major (e.g. planar) side of the support member 100, e.g. by adhesive bonding or by ultrasonic welding, such that leakage past the rim 103 of the support member 100 and the divider plate 201 is prevented. In a specific embodiment, a divider plate 201 is provided on both major sides of the support member 100. All or a subset of the divider plates 201 have openings 206 which correspond to the openings 112 in the wall 102 for allowing cells 130 to pass therethrough. Preferably, a gasket 205 (made from e.g. an elastomer such as rubber, or from a soft plastics material) is provided at each divider plate 201, each said gasket 205 having openings 206 which correspond to the openings 112 in the wall 102 of the support member 100 for receiving cells 130, such that said gasket 205 seals around each cell 130 to deter leakage of coolant fluid 120 from the areas and / or chambers of the support member. Said gasket 205 is fixed (e.g. bonded to the divider plate 201, integrally-moulded with the divider plate 201, or otherwise fixed) to the respective divider plate 201. As an alternative (not shown), separate gaskets or o-rings can be provided in the divider plate 201 around individual openings 206 or around a subset of openings 206.

[0065] In alternative embodiments a divider plate 201 may only be provided on one major side of the support member 100, in which case an inter-module gasket (not shown) can be provided between the support member 100 of one module and the divider plate 201 of a next successive module, such that each divider plate 201 serves to not only bound coolant fluid 120 circulating in the support member 100 to which the divider plate 201 is fixed, but also serves to bound coolant fluid 120 circulating in an adjacent support member 100.

[0066] The effect of the above-described arrangements including gaskets 205 and end plates 201 is that when the resulting sub-assembly (comprising divider plate[s] 201, support member 100 and gasket[s] 205) is assembled together with other adjacent subassemblies, leakage of coolant fluid 120 from between the sub-assemblies and from between the components of each sub-assembly is substantially prevented.

[0067] As mentioned, one or more of the divider plates 201 optionally comprise openings 206 which correspond to cell position openings 112 in the support members 100, so as to permit cells 130 to extend through the divider plates and thereby permit individual cells 130 to be cooled by the coolant circulating through multiple support members 100. Permitting cells to straddle multiple support members 100 can further assist to equalise and average out the cooling effect provided to individual cells (especially cells straddling the first and fourth chambers 106, 117, which in use tend to experience relatively large differences in coolant temperature between the two chambers that they straddle, due to the first and fourth chambers being at opposite ends of the overall flow path through the support member, compared with cells straddling the second and third chambers. In such cases, the divider plates 201 incorporate a gasket 205 or separate gaskets or o-rings as described above, so as to prevent leakage of coolant fluid 120 around cells 130 as they pass through each divider plate 201.

[0068] Furthermore, as shown in Figure 4b, an end (or each end) of said stack can be capped by a respective end plate 202 which provides mechanical support (e.g. to gasket 205, cells 130, and associated electrical connections) and optionally further assists with enclosing the associated area 104, 114 of the adjacent end support member 100. Optionally, one or both end plates 202 can comprise a coolant feed passage 204 for supplying coolant 120 (e.g. from a pump 170) to the inlet gallery 202. Optionally, each support member 100, divider plate 201, gasket 205 and end plate 202 can comprise further holes for receiving rods / fixings for fastening the sub-assemblies together into the assembly. In operation, coolant is introduced into the inlet gallery 203, from where it passes through the inlet passage 113 into the first chamber 106 and then travels via the second chamber towards the one or more outlets 105 (optionally via the orifices 118 into the second area 114 comprising third chamber 116 and optionally the fourth chamber 117) wherefrom it exists the assembly 200. Thus, having traversed the array of cells 130, the coolant fluid 120 arrives back into the housing 110 (preferably at an upper portion of said housing 110), having passed around and absorbed heat from all of the cells 130. The hot coolant fluid 120 can then be drawn off by a pump 170, and then optionally filtered and cooled by filter and heat exchanger 171, before being returned to the housing 110 and circulated around the array of cells 130 again via the inlet 101.

[0069] In more context, as shown in Figures 5 and 6, in an embodiment a battery pack 300 for a vehicle 400 is provided. Said battery pack 300 comprises a housing 110 for containing at least one battery cell 130 (e.g. by virtue of containing an assembly 200 as previously described) and a coolant fluid 120 for cooling said at least one battery cell 130. Optionally the housing 110 comprises a filler extension 140, and / or extension volumes 165, 166 for facilitating coolant fluid 120 handling. Preferably, the battery pack 300 comprises an array of battery cells 130 which are electrically connected in a series arrangement, a parallel arrangement, or a combination of series and parallel arrangements, to achieve a given voltage and current capability, such as in an arrangement having a plurality of modules (e.g. 12 modules), with each module comprising a number of (e.g. 15) series-connected groups of cells, each group comprising a number of (e.g. 4) parallel-connected cells 130. In an embodiment, a BMS (Battery Management System) 197 connects to pressure and / or temperature sensors and / or electrical nodes at various points across the array of cells 130 in each module, and monitors characteristics such as voltage and temperature for the cells 130, and determines error conditions therefrom and / or signals a warning of such events (such as a cell thermal event wherein a cell temperature exceeds a threshold temperature). Optionally the battery cells 130 are 21700-format cells, which is a popular cell format providing a degree of future-proofing by way of increasing the likelihood of a future upgrade to improved cells with the same package format. In one example, 14 battery modules are employed, with each module comprising 12 series-connected groups of 4 parallel-connected cells 130, however, a greater number or a smaller number of modules, parallel-connected cells and / or serial-connected cells can be used.

[0070] The housing 110 is arranged to contain a coolant fluid 120, which can be any suitable coolant such as a dielectric oil (e.g. Lubrizol Gen 1, 3M Novec 7000, M&l Mivolt DF7), or if precautions against short circuits are taken in the design of the battery cell interconnections then other coolants such as water can be used. Note: any Trade Marks in the preceding sentence are properties of their respective owners. Said housing 110 can be made of any suitable material that has sufficient mechanical strength, is impermeable, is compatible with the intended coolant, and is suitable for ease of manufacture, for example (but not limited to): any of stainless steel, aluminium, other metals, a plastics material, a composite material, or a combination thereof, depending on required coolant and / or cell carrying capacity, as will be appreciated. Optionally, and in use, the housing 110 is completely or substantially completely filled with the coolant fluid 120, and a desired configuration of battery cells 130, i.e. the volume within the housing 110 is completely filled with battery cells 130 as far as possible or desired, and the remaining spaces between the cells 130 are filled with coolant fluid 120, preferably with no air space remaining in the housing 110. This maximises the number of cells 130 within the housing 110, thereby maximising energy storage capacity, and tends to ensure that all cells 130 are permanently covered in coolant fluid 120, even when the battery pack 300 is subjected to physical forces such as when a vehicle 400 to which such a battery pack 300 is fitted is cornering / accelerating / braking hard.

[0071] Examples of the present disclosure provide a solution to the above problem of how to ensure that every cell in the housing 110 is substantially equally cooled by the circulating coolant fluid. This reduces differences in operating temperatures between cells 130, and since the consequence of even a single cell overheating is that the power draw from the battery pack 300 as a whole has to be reduced until the overheated condition ends, the likelihood of having to reduce power draw is reduced, and thereby the battery pack 300 is able to be used at its maximum power rating for more of the time. This in turn may allow a lower rated battery pack 300 to be used (e.g. one constructed from fewer cells 130), which in turn assists with packaging of the battery pack 300 within the vehicle 400 envelope, and other advantages follow such as improved handling by virtue of a lowered mass and / or centre of gravity. The above-described arrangement also reduces the quantity of coolant fluid 120 that is required to be held in the battery pack 300, since the heat dissipated by the cells 130 is more evenly absorbed by the coolant fluid 120. This reduction in coolant fluid volume in turn reduces the size and weight of the battery pack 300. This in turn enables a reduction in the required strength and weight of the battery pack 300, in particular of the housing 110. By way of example, a coolant fluid 120 volume of approximately 7 litres can be used to completely surround the cells 130 in use by the coolant fluid 120. Preferably, but not essentially, the housing 110 when in use is substantially filled with battery cells 130, meaning that there is no remaining space inside the housing 110 large enough to add further cells 130. This results in increased energy storage capacity for a given battery assembly weight and volume (i.e. an increased energy storage density), and also permits more flexibility in the design of the shape of the housing 110, thereby permitting a battery pack 300 with greater storage capacity to be fitted to a given vehicle 400. An example battery pack 300 weight according to the described embodiments is around 110kg, including coolant fluid and associated components.

[0072] As shown in Figures 5 and 6, in certain embodiments a pump 170 is preferably provided for circulating coolant fluid 120 around the battery cells 130, thereby cooling and / or pre-heating the cells 130, and assisting with minimising the temperature difference between cells 130, with the above-described benefits. In such embodiments, a portion of the housing 110 is provided with an opening for connection to the pump 170. Preferably the inlet side of the pump 170 is connected to the opening such that in use the pump 170 receives relatively hot coolant fluid 120 that has risen into an upper portion of the housing 110 (e.g. preferably assisted by gravitational action), and the outlet side of the pump 170 is connected to the coolant inlet gallery 211 so as to form a coolant circuit such that the received coolant fluid 120 is circulated around the battery cells 130. A contrary flow direction can optionally alternatively be employed, without benefiting from gravitational assistance to the flow. The action of the circulating fluid helps to minimise temperature differences between the cells 130, and thereby helps to avoid de-rating of the battery pack 300. Optionally, a filter (not illustrated) can be included in the coolant circuit for filtering out any debris in the coolant fluid 120. Optionally, a cooler unit (or heat exchanger) 171 can be included in the coolant circuit for reducing the temperature of the coolant fluid 120 before it is returned to the battery pack 300, which further reduces the likelihood of any cells 130 overheating and necessitating de-rating of the battery pack 300. When a pump 170 is provided, a sufficient flow rate can be employed in operation such that any air / gas is eventually swept by the flow into an upper portion of the housing where it can be removed or handled appropriately.

[0073] Also shown in Figure 6, the battery pack 300 further optionally comprises an enclosure 180 that is attached to the housing 110, and which is provided for enclosing electronic components 185 that are associated with the battery pack 300. By way of example, the electronic components 185 are high voltage components involved in the conversion of power from the battery cells 130. Preferably, the enclosure 180 is sealed from the interior of the housing 110, such that the enclosure 180 can be dry (i.e. not containing coolant fluid 120). Since the components in this enclosure 180 are high voltage components, they operate at lower currents, and therefore resistive heating losses are lower than in the lower voltage components (e.g. the battery cells 130) of the battery pack 300, therefore liquid cooling is not required. By keeping the high voltage enclosure 180 free of coolant fluid 120, weight is further reduced, as well as environmental impact being reduced, and safety being improved. Further, with reference to Figures 5-8, the high voltage enclosure 180 can be provided with an electrical disconnection point 196 (e.g. a manual service disconnect switch), which when the battery pack 300 is located in a vehicle 400 can be conveniently placed for operation by service personnel from inside or from underneath the vehicle 400. The high voltage enclosure 180 further comprises at least one high voltage connector 186 for connecting the battery pack 300 to various components on a vehicle 400 that require power supply / storage provided by the battery pack 300 (e.g. a Power Distribution Unit can be connected to the battery pack 300 via a high voltage connector 186, which Power Distribution Unit feeds one or more electric drive units, or alternatively the Power Distribution Unit can be housed inside the high voltage enclosure 180 in which case multiple high voltage connectors 186 can be included on the high voltage enclosure 180).

[0074] As shown in Figures 6 and 7, such a battery pack 300 can be provided with housing 110 dimensions suitable for installation into a vehicle 400 in a position behind a seating area 420 and in front of the rear wheels 410 of the vehicle 400. This location is assisted by the illustrated relatively low and wide aspect ratio of the housing 110, which is assisted by virtue of the above-described features which tend to ensure that each battery cell 130 is equally cooled even under heavy mechanical forces. Thus, a vehicle 400 can be provided comprising a battery pack 300 as described herein.

[0075] Optionally, as shown in Figures 5 to 7, the battery pack 300 can also comprise a mounting portion 190 upon which various components associated with the battery pack 300 can be mounted, and which can also be used to provide mechanical mounting of the battery pack 300 to the vehicle 400. Such components can include, but are not limited to, the coolant pump 170, the coolant filter (not shown), the heat exchanger 171 for cooling coolant fluid 120, a fuse 195 (with fuse access 194), a battery management system, a shunt 198, a current sensor 199, a high voltage contactor 188, a gas venting port, a high voltage connector 186, and an electrical disconnection point 196. Thus, the components are easily accessible for servicing. As shown in Figures 6 and 7, a cover can be provided over the mounting portion 190. As shown in particular in Figure 6, the mounting portion further provides a mounting location for components such as low voltage components 191 and access to a battery management system 197, and also cooperates with a longitudinal (service or “transmission”) tunnel space in the vehicle 400 floor, to assist with safe routing of high voltage cables 187. Access can also be provided from underneath the vehicle, e.g. on the underside of the housing 110, for removing / replacing cells 130 or cell modules, e.g. via a removable panel.

[0076] The mounting portion 190 further provides a position for mounting such components which is in a safer location in a crash scenario. For example, said gas venting port (which may be one of one or more high pressure gas venting ports of e.g. 30mm diameter for emergency venting gas from the housing 110 in the event of a cell failure) can thus be mounted away from sources of ignition such as hot exhaust pipes or high voltage cables or components, thereby increasing safety in the event of an emergency.

[0077] Additionally, the position of the high voltage component enclosure 180 on the housing 110 behind the seating area 420, provides a safe and compact packaging option, which also assists with minimising the length of electrical busbars from the cells to the high voltage components inside the enclosure 180. The location of the electrical disconnection point (manual service disconnect) 196 on top of the high voltage enclosure 180 provides for convenient access by service personnel from inside the vehicle, enabling the vehicle to be made safe before raising it on a lift or jack. Also shown in Figure 6 is a chassis crossmember (or cross-car load path, labelled “X-Car load path” in the Figure) 192 of the vehicle 400, which crossmember 192 can be arranged in cooperation with the shape of the mounting portion 190 for maximally efficient packaging and maximum strength.

[0078] As shown in the example electrical schematic diagram of Figure 8, an array of battery cells 130 are arranged in circuit, with the positive side of the array being connected to a main fuse 195 for protecting against over-current situations, and in turn to an electrical disconnection point (manual service disconnect) 196 for operation by servicing personnel to isolate electrical battery power from the vehicle 400, a shunt resistor 198 (e.g. for sensing current by producing a measurable voltage drop when current flows through it), via a current sensor 199 (e.g. a hall-effect current sensor), and a first high voltage contactor (e.g. a relay) 188 for selectively connecting that series of components to the positive terminal of the high voltage connector 186. From the negative terminal of the high voltage connector 186, a further high voltage contactor (relay) 188 can be provided for selectively connecting the negative terminal to the negative side of the array of battery cells 130. A battery management system 197 is connected to, and between, the cells 130, to perform monitoring and failsafe fall-back configuration / operation of the battery cell array, based on monitoring at least one or more parameters including voltage, current and temperature. Thus, if one or more cells 130 are found to have parameters which are out of specification, the battery management system can detect an error, and / or take action such as opening contactors or limiting current flow to prevent damage.

[0079] The battery assembly 200 described above can be provided with or without the housing 110, and with or without battery cells 130 and / or coolant fluid 120 inside the housing 110. It will be understood that the battery assembly 200, even if provided without housing 110, cells 130 and / or fluid 120, is nevertheless provided with features which provide for more effective cooling of battery cells 130, once installed and in operation, submerged in coolant fluid 120.

[0080] Further, a method of manufacturing a battery assembly 200 for a vehicle 400 can comprise: assembling a plurality of support members 100 together (e.g. by stacking them next to each other such that their walls are parallel and adjacent) to form the assembly 200; and optionally inserting a plurality of cells 130 into the support members 100 of the assembly 200; and further optionally providing a housing 110 for containing a coolant fluid 120 and the assembly 200; and further optionally inserting the assembly 200 into the housing and / or substantially filling the housing 110 with coolant fluid 120. Optionally, filling the housing 110 with coolant fluid 120 is achieved by first evacuating those components and then filling them with coolant fluid 120. Optionally, a divider plate 201 is joined to a first major (planar) side of the support member 100, e.g. by adhesive bonding or by ultrasonic welding. Optionally, a gasket such as an elastomeric gasket 205 is provided on the other major (planar) side of the support member 100, said gasket comprising holes corresponding to openings 112 in the support member 100 for supporting cells 130, said holes in said gasket for receiving cells 130 and for sealing around cells 130 for preventing leakage of coolant fluid 120 around cells 130. Optionally, said gasket 205 is provided with a perimeter arranged for sealing against the rim of the support member 100. Optionally, said divider plate 201, support member 100 and gasket 205 are assembled into a sub-assembly, and said gasket 205 is arranged for sealing against an adjacent similar sub-assembly or end plate 202.

[0081] Optionally, the method further comprises providing the housing 110 with an opening for fluid connection with a pump 170 to enable coolant fluid 120 to be circulated around the at least one battery cell 130. Optionally, the method further comprises mounting a battery pack 300 comprising the housing 110 to a vehicle 400, in front of the rear wheels 410 of the vehicle and behind a seating area 420 of the vehicle, wherein a longest horizontal dimension 113 of the housing 110 is aligned transversely relative to the vehicle 400. Further optionally, the method comprises fitting a mounting portion 190 of the battery pack 300, that extends forwards from a central portion of the housing 110, into a longitudinal tunnel area of the vehicle 400, wherein the mounting portion 190 is provided for mounting components associated with the battery pack 300, said components including one or more of a coolant pump 170, a coolant filter, a heat exchanger 171 for cooling coolant fluid 120, a fuse 195 mounting area, and an electrical disconnection point 196. Further optionally, the method comprises attaching an enclosure 180 to the battery pack 300, wherein said enclosure 180 is for enclosing electronic components that are associated with the battery pack 300 including at least one of a high voltage electronic component 185 and a high voltage connector 186, and providing that the enclosure 180 is sealed from the interior of the housing 110.

[0082] By virtue of the above-described features it can be avoided that thermal runaway of a particular cell 130 causes pack de-rating and / or damage to other cells 130, or at least the amount of such potential effects can be reduced. By way of a further optional embodiment, one or more temperature and / or pressure sensors can be installed in one or more of: a battery cell 130 or module cavity; the housing 110; and / or an area and / or chamber of the support member 100. By monitoring said sensors, a cell thermal / venting event can be detected, e.g. by triggering a detection when a temperature and / or pressure threshold is exceeded, and / or when a temperature and / or pressure change in a predetermined time interval is exceeded. Further, the housing 110 can be made of aluminium, and to aid containment of hot gases / flames within the housing 110, the housing 110 can be provided with a heat shield and / or a heat protective coating in vulnerable areas close to cells 130. Such features can help to give a sufficiently timely warning to vehicle occupants that they can leave the vehicle safely.

[0083] Various modifications may be made to the preferred embodiments described herein without departing from the scope of the invention as defined by the accompanying claims. Many combinations, modifications, or alterations to the features of the above embodiments will be readily apparent and are intended to form part of the disclosure. Any of the features described specifically relating to one embodiment or example may be used in any other embodiment by making appropriate changes as apparent in the light of the above disclosure.

Claims

CLAIMS1. A support member for a fluid-cooled battery, said support member arranged for supporting battery cells, the support member comprising: a generally planar wall; a rim extending at least partially around the wall and extending in a normal direction from a first side of the wall so as to at least partially bound a first area for containing a fluid; an inlet for admitting fluid into the first area; and one or more outlets for allowing fluid to outflow; wherein the first area is divided into at least a first chamber and a second chamber, each chamber arranged for housing at least a part of each cell of a respective plurality of cells, wherein the inlet is arranged in fluid communication with the first chamber, the second chamber is in fluid communication with the one or more outlets, and wherein a respective divider between each successive pair of chambers comprises a plurality of channels for fluid communication therebetween.

2. The support member of claim 1 , wherein the inlet is in direct fluid communication with the first chamber.

3. The support member of any preceding claim, wherein at least a portion of the first chamber is located proximate to the inlet and at least a portion of the second chamber is located distal from the inlet.

4. The support member of any preceding claim, wherein the inlet and at least a portion of the first chamber is located at a region of the support member that is intended to be uppermost when in use, and at least a portion of the second chamber is located at a region of the support member that is intended to be lowermost in use.

5. The support member of any preceding claim, further comprising one or more additional chambers interposed between the first and second chambers on the first side.

6. The support member of any preceding claim, wherein each divider is arranged generally perpendicular to a mean direction of fluid flow from the first chamber to the second chamber.

7. The support member of any preceding claim, wherein the channels are substantially evenly spaced along the divider in a direction that is perpendicular to the mean direction of fluid flow from the first chamber to the second chamber.

8. The support member of any preceding claim, wherein each channel is aligned with a cell position, and optionally wherein the number of channels is equal to the number of cells along the length of the respective divider.

9. The support member of any preceding claim, wherein the wall is arranged for supporting the cells, and optionally wherein the wall further comprises a plurality of openings, each opening provided for receiving and supporting a respective cell, and optionally wherein the diameter of each opening is matched to the diameter of the cells so as to prevent leakage through an opening when a cell is present in an opening.

10. The support member of any preceding claim, wherein the rim also extends in an opposite normal direction from a second side of the wall so as to at least partially bound a second area for containing fluid.

11. The support member of claim 10, wherein the second area comprises at least a third chamber, wherein at least a portion of the third chamber is located adjacent the second chamber.

12. The support member of claim 11, wherein the wall portion comprises a plurality of orifices in a region distal from the inlet such that the second chamber is in fluid communication with the third chamber, and optionally wherein the orifices are provided at positions between cells, and optionally wherein the number of orifices is equal to the number of cells minus one, counted along the length of a divider.

14. The support member of any preceding claim, wherein the first chamber further comprises a space for receiving fluid from the inlet, the space arranged for facilitating fluid flow in a crosswise direction that is substantially parallel to the wall and perpendicular to the mean direction of fluid flow from the first chamber to the second chamber, and the space having a cross-section that is arranged for balancing respective flows of fluid between respective cells from the space in the first chamber towards the second chamber via the plurality of channels, and optionally wherein the cross-section varies along the crosswise direction.

15. The support member of any preceding claim, wherein the inlet comprises a tubular inlet hole through the wall of the support member, and the support member further comprises an inlet passage connecting the inlet hole to the first chamber.

16. The support member of claim 15 when dependent upon claim 14, wherein the inlet hole is provided in the support member at a position adjacent to the first chamber such that a resulting angle, at which the inlet passage leads from the inlet hole to the space of the first chamber, is optimised to equalise respective flows of fluid passing between respective cells in the first chamber, thereby aiding equalisation of respective flows of fluid passing through each respective one of the plurality of channels.

17. The support member of any preceding claim, wherein the support member comprises two adjacent halves, each half comprising the features of any of the preceding claims.

18. The support member of claim 17, wherein both halves share a common inlet wherein an axis of symmetry passes through a centre of the common inlet, which axis lies in the plane of the wall and is generally parallel to the mean direction of fluid flow from the first chamber to the second chamber, wherein: each half is mirrored with respect to the other half about the axis of symmetry; or each half is rotationally symmetric about the axis of symmetry.

19. The support member of any of claims 12 to 18, wherein in use the fluid flows in a first mean direction from the first chamber to the second chamber, then through the wall from the second chamber to the third chamber, and then in a second mean direction from the third chamber to the one or more outlets, wherein the second mean direction is substantially opposite to the first mean direction.

20. A sub-assembly comprising a support member of any of claims 1 to 19, a dividing plate joined to at least one major side of the support member, and a gasket provided at the dividing plate to seal around the periphery of a cell located through an opening in the dividing plate.

21. An assembly comprising a plurality of the support members of any of claims 1 to 19.

22. The assembly of claim 21, wherein the assembly further comprises respective dividing plates interposed between adjacent support members, each dividing plate for inhibiting fluid flow between chambers of adjacent support members, and optionally wherein each dividing plate is joined to a side of a respective support member.

23. The assembly of claim 22, wherein one or more of the dividing plates comprises respective openings corresponding to at least some of the openings in the walls of each of the support members, and optionally wherein the respective openings correspond to at least the inlet opening and / or the openings for supporting the cells.

24. The assembly of any of claims 21 to 23, further comprising respective gaskets provided at the dividing plates, each gasket provided at the dividing plate to seal around the periphery of a cell located through an opening in the dividing plate.

25. The assembly of any of claims 21 to 24 when dependent upon claim 15, wherein the tubular inlet holes of each of the support members of the assembly are aligned with each other so as to form an integral inlet gallery, and optionally wherein the assembly comprises, at an end, an end plate comprising a coolant feed passage for supplying coolant to the inlet gallery.

26. A method of producing a battery for a vehicle, comprising assembling a plurality of the support members of any of claims 1 to 19 into an assembly according to any of claims 21 to 25.

27. A battery assembly for a vehicle, comprising: a housing, for containing a coolant fluid and at least one battery cell to be cooled by said coolant fluid; and the assembly of any of claims 21 to 25.

28. The battery assembly of claim 27 wherein the housing contains at least one battery cell.

29. The battery assembly of any of claims 27 to 28, further comprising: one or more pressure or temperature sensors; and a monitoring device that monitors said sensors to determine based upon their outputs whether or not a cell thermal event has occurred, and upon such determination trigger a warning to a vehicle occupant.The battery assembly of any of claims 27 to 28, wherein the housing is completely filled or substantially completely filled with coolant fluid surrounding at least one battery cell, and preferably wherein the coolant fluid is a dielectric oil. The battery assembly of any of claims 27 to 30, wherein the housing has an opening therein for fluid connection with a pump to enable coolant fluid to be circulated around the at least one battery cell, and optionally arranged such that when in operation with said pump, fluid that has been heated by one or more battery cells is withdrawn from the housing and is returned to the array of cells after having been cooled by passing through a cooler unit. The battery assembly of any of claims 27 to 31 , wherein the housing has a first horizontal dimension that is transverse when mounted in a vehicle, and which is greater than a second horizontal dimension that is orthogonal to the first horizontal dimension, wherein a plurality of the support members of any of claims 1 to 19 are stacked in parallel along a direction of the first horizontal dimension. The battery assembly of any of claims 27 to 32, wherein the battery assembly further comprises a mounting portion extending forwards from a central portion of the housing, for mounting components associated with the battery assembly including at least one of a coolant pump, a coolant filter, a heat exchanger for cooling coolant fluid, a fuse, a manual switch, a high voltage contactor, a gas venting port, a high voltage connector, and an electrical disconnection point. The battery assembly of any of claims 27 to 33, further comprising an attached enclosure for enclosing electronic components that are associated with the battery pack including at least one of a high voltage electronic component, a fuse, a high voltage contactor, a current sensor, a high voltage connector, and an electrical disconnection point, wherein the enclosure is sealed from the interior of the housing. A motor vehicle including apparatus as defined in any preceding claim.

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