SE2350291A1 - Thermal management of a liquid cooled module - Google Patents

Abstract

Described is among other things a liquid cooled module (1). The liquid cooled module provides improved heat dissipation and improved flow in the liquid cooled module (1).

Description

Technical fieid The present invention reiates to a liquid cooled module comprising a housing, a plurality of heat generating components arranged in the housing, and a iiquid for thermal management of the heat generating components.

Background There is an increased use of heat generating devices such as electric components and rechargeable batteries. Appiications include for example, energy storage, energy transformation to powering electric equipment and vehicles or as a power back up in stationary applications. During operation, the heat generating components generate heat which needs to be dissipated effectively to allow safe functioning of the components and prevent faiiure of the module in which such heat generating components are housed. The performance of the heat generating component is to a iarge extent limited by the avaiiable thermal management techniques for keeping the component within an appropriate temperature range. ln for example battery applications, it is known to have thermal management systems employed within the battery moduie to control the operational temperature of the battery celis within an optimal temperature range. increased energy storage capacity and reduced charging times have led to a strive for more efficient thermai management in general, and dissipation of generated heat in particuiar. One commonly empioyed thermal management method is known as immersion cooling, which also referred to as iiquid submersion Cooling. This is the practice of submerging components, such as e.g., battery celis, in a thermally conductive liquid. Thus, the heat may be transferred directly from the heat source, e.g., battery cell, electronics, printed circuit board, to the working fluid and dissipated through a heat exchanger located elsewhere.

With the ever-increasing performance requirements regarding storage capacity and strive for more space efficient systems, there is a need for improved and more efficient thermal management techniques.

US2020266506 discloses a battery module including a housing and a plurality of battery ceils arranged in a battery stack received within the housing. The battery celis are rectangular and has two parallel main surfaces. The battery modules in the stack are arranged so that the main surfaces of neighboring cells in the stack is in close contact with each other. The battery module further inciudes an inner cover disposed between the housing and the plurality of battery ceils. The inner cover includes a top surface facing the housing and a bottom surface facing the plurality of battery ceils. The inner cover aiso includes a pluraiity of fluid channeis defined on the bottom surface and extending along a length of the inner cover. Each of the piurality of fluid channels is configured to receive a fluid, such as a thermal management liquid. The fiuid channeis lead the fluid from one side of the battery ceil to the opposite side of battery celi in a direction perpendicuiar to the main surfaces of the battery celis and by that improve the circulation of the fiuid within the battery moduie. The inner cover is also provided with openings disposed above the battery ceils for letting out gases generated by the battery celis.

US4522898 discloses a battery with a housing containing a plurality of battery celi as weil as a cooling medium. The battery cells are cylindrical and arranged adjacent to each other with their iongitudinal axes in parallei so that elongated spaces for housing the cooling medium are formed between the battery cells. The battery comprises a distributor plate provided in the interior of the housing for feeding and distributing the cooling medium to the battery celis. The distributor plate is provided with openings through which the cooling medium can be fecl to the spaces between the battery celis. The distributor plate is disposed either above the upper ends of the battery ceils or below the lower ends of the battery cells. The cooling medium is iniet to an open space above the battery cells. The cooiing medium flows through the openings in the distributor plate and in the elongated spaces between the battery cells. This battery is mainly intended with air as a medium.

There is a constant desire to improve the thermal management of iiquid cooled modules and to thereby increase the performance of the heat generating components housed inside the module. Hence there is a need for an improved liquid cooled module.

Summary lt is an aim of the present invention to at least partly overcome the above problems, and to provide an improved thermai management of a liquid cooled module.

This aim is achieved by a liquid cooled module in accordance with the appended claims. ln accordance with one aspect a liquid cooled module comprising a plurality of heat generating components arranged so that spaces for housing a moving fluid are formed around the heat generating components is provided. The liquid cooled module has a liquid seaied casing enclosing the heat generating components. At least one restricting member is located in the flow path the moving fluid. The restricting member can be placed in the spaces. By placing a member/element in the flow path the fiow around the heat generating components such as battery cells can be improved. Restricting members can typicaily be placed in a plurality or all of the spaces. ln another embodiment a manifoid is used as a restricting member to aid in improving the distribution of the moving fluid. Other types of restricting members can also be used. The use of a restricting member leads to an improved heat transport and the heat generating components can be cooled more efficiently. The plurality of heat generating components can advantageously be cyiindrical in shape to allow for an efficient space use, but other shapes such as prism shapes are also possible. ln accordance with some embodirnents a pump for pumping the fluid is located inside the liquid sealed casing. Hereby the liquid cooled module can be self-contained and no parts external to the casing are required. For example, the liquid cooled module can then be used as a liquid cooled (stand-alone) battery pack that can easily be moved around and used as a power back-up in a car or at a home. The pump can for example be an Eiectrohydrodynamic (EHD) pump. Typically, the fluid is moved in an axial direction of the heat generating components in fluid channels formed in the spaces and the length of the fluid channels correspond to the axial length ofthe heat generating components or at least almost the length of the heat generating components such as at least 80% of the length of the heat generating components. ln accordance with some embodiments, the pump is cylindrical in shape. Hereby the use of space inside the casing of the liquid cooled module can be improved when other components such as battery cells also are cylindrical. ln accordance with some embodiments, the restricting members are pin shaped and located in the spaces between the heat generating components. Hereby a good flow restriction can be achieved and the restricting members can be designed to have additional functions such as to allow thermai expansion of the heat generating components. ln accordance with some embodiments, the liquid cooled module comprises a distributor plate disposed between the casing and the heat generating components. The distributor plate is provided with a piurality of openings for distributing the fluid to the spaces between the heat generating components and a manifoicl structure comprising a plurality of fluid channels arranged between the at least one fluid entrance and a distributor plate to guide the fluid from the at least one fluid entrance to the openings in the distributor plate. The manifold can act as a restricting member to improve the distribution of the moving fluid. Hereby a more even and thereby improved distribution of liquid over all heat generating components can be obtained. Further, when a manifold structure is provided, the manifold structure can be integrated in some part of the casing. Hereby manufacturing and assembly is facilitated. ln accordance with some embodiments, each of the fluid channels has an open side facing the distributor plate, and the distributor piate is tightiy attached to the manifold structure so that the open sides of the channels are partly seaied by the distributor piate. Hereby the cooling can be improved. ln accordance with some embodiments, the distributor plate is made of an electricaliy conducting material and is configured to act as an electricai connector. Hereby the distributor piate can be made to have multiple functions and there is need for a separate electrical connector. ln accordance with some embodiments, at least one at least partly cylindricai shaped thermai expansion compensating structure is provided. This can be a separate part or it can be formed by the restricting members, or both. For example, the restricting members can be formed by an eiastic material to allow for thermal expansion. ln accordance with some embodiments, the restricting members are formed by an electric conductive material to allow for electric connection. ln accordance with some embodiments, the iiquid sealed casing comprises flanges and or at least one corrugated section. Hereby thermal dissipation can be improved and heat can be let out via the casing. This is particularly useful when there is no liquid inlet/outlet from the liquid cooled module in that heat then can be efficientiy let out from the liquid cooled module. ln accordance with some embodiments, at least one partly cylindricai heat sink member located on a wali of the casing or at the bottom of the casing, and where at least one partly cylindrical heat sini< member is provided with at least one flange. Hereby heat dissipation can be improved by using space not used inside the iiquid cooled casing to facilitate heat dissipation. ln accordance with some embodiments, the restricting members comprise a hollow section allowing compression of the restricting members. Hereby compression of the restricting members is eased. ln accordance with some embodiments, the restricting members are formed by an electrically isoiating material. Hereby efficient isoiation between heat generating components can be obtained. ln accordance with one aspect of the invention a iiquid cooied module, in particular a battery module comprises a plurality of battery cells arranged so that spaces for housing a fluid are formed between the battery cells, a casing enclosing the battery cells, wherein the casing is provided with at least one fluid entrance, and a distributor plate disposed between the casing and the battery cells and provided with a piurality of openings for distributing the fluid to the spaces between the battery cells. According to this aspect, the module comprises a manifold structure comprising a plurality of fluid Channels arranged between the at least one fluid entrance and the distributor plate to guide the fluid from the at least one fluid entrance to the openings in the ciistributor plate.

The channels in the manifold structure and the distributor plate make it possible distribute the fluid from the at least one fluid inlet evenly to the spaces between the battery cells. The fluid channels mal The fluid channels are arranged in the manifold structure which serves as a mechanical structure housing the fluid channels. The manifold structure makes it easy to manufacture the channels.

The openings in the distributor plate are arranged to correspond to the positions of the spaces between the battery cells so that the flow of fluid is guided towards the spaces between the battery cells. Thus, the flow of fluid can be evenly distributed between the battery cells.

According to one aspect, the battery cells are elongated and arranged with their longitudinal axes in parallel. Thus, the spaces between the battery cells are elongated and arranged in parallel.

According to an aspect, the battery cells are cylindrical and arranged with their symmetry axes in parallel.

According to an aspect, the fluid channels are elongated and extend in a plane perpendicular to the axes of the battery cells.

According to an aspect, the distributor plate and accordingly the plurality of openings in the distributor plate is arranged below or above the spaces between the battery cells.

According to an aspect of the invention, the manifold structure is plate shaped and defines a piane. The plurality of fluid channels is arranged so that they extend in the plane defined by the manifold structure.

According to an aspect of the invention, each of the fluid channels has an open side facing the distributor plate, and the distributor plate is tightly attached to the manifold structure so that the open sides of the channels are partly sealed by the distributor plate. ln one aspect, each of the fluid channels extend over one or more of the openings in the distributor plate or ends in one of the openings in the distributor plate so that the openings in the distributor plate are in fluid communication with the fluid channels.

According to an aspect of the invention, the distributor plate is made of an electrically conducting materiai, and the distributor plate has an additional function as electrical connector. The distributor plate is electrically connected to at least some of the battery cells.

According to an aspect of the invention, the manifold structure has a bottom surface facing the distributor plate, the plurality of fluid channels defines elongated openings in the bottom surface of the manifold structure, and the distributor plate is tightly attached to the manifoid structure so that the eiongated openings in the bottom surface of the manifold structure are partly sealed by the distributor plate. The elongated openings in the manifold structure are arranged so that they face the openings in the distributor plate so that the fluid in the fluid channels can leave the channels through the openings in the distributor plate. Each eiorigated opening in the manifold structure faces one or more of the openings in the distributor plate. Thus, one fiuid channel may suppiy fluid to one or more openings in the distributor plate. The parts of the elongated openings, which do not face the openings in the distributor plate, are sealed by the distributor plate. Thus, the distributor plate forms the bottoms of the fluid channels. This aspect makes it easy to manufacture the fluid channels.

According to an aspect ofthe invention, the distributor plate is made of a flexible material and the distributor plate is pressed against the manifoid structure.

According to an aspect of the invention, the casing comprises a first vvali arranged on one side of the battery cells, and the manifold structure is attached to the first wall. To have a separate manifold structure makes it easy to manufacture the manifold structure.

According to an aspect of the invention, the fluid channels have an upper side facing the first wall and a lower side facing the distributor plate. The upper sides of the fluid channels are opened and form elongated openings in an upper surface of the manifold structure, which elongated openings are facing the first wail. The lower sides of the fiuid channels are opened and form elongated openings in a bottom surface of the manifold structure, which elongated openings are facing the distributor plate. The distributor plate is tightly attached to the manifold structure so that the elongated openings in the bottom surface of the manifold structure are partly sealed by the distributor plate. The fluid channels are defined by the first wall, the manifold structure, and the distributor plate. The upper surface of the manifoid structure is tightly attached to the first Wall so that the eiongated openings in the upper surface of the manifoid structure are sealed by the first wall. Thus, the first wall and the distributor plate seal the fluid channeis in the manifoid structure. This aspect facilities the manufacturing of the fluid channels.

According to an aspect of the invention, the battery cells are elongated and arranged in parallel, and the first Wall is arranged perpendicular to the iongitudinal axes of the battery celis.

According to an aspect of the invention, the at ieast one flow entrance is arranged in the first wall.

According to an aspect of the invention, the at ieast one fiow entrance is arranged between the first wali and the manifoid structure.

According to an aspect of the invention, the casing comprises a second wail arranged on an opposite side ofthe battery celis, and the second wall is provided with at least one fiuid outlet. ln this embodiment, the flow entrance and the flow outiet are arranged above and beiow the battery ceils, respectively. Thus, the fiow of fiuid in the spaces between the battery ceils is parallel to the axial direction ofthe battery ceils, and in direct contact with the envelop surface of the individual battery cells. This will provide an efficient cooling of the batteries.

According to an aspect of the invention, the manifold structure is integrated into the first wail. Thus, the fluid channels are arranged in a wall of the casing. This will reduce the number of parts of the battery module.

According to an aspect of the invention, the at least one fluid entrance is arranged at a distance from the edges of the first wali, and the first wall is provided with an inlet channei arranged between one edge of the first wall, and the fluid entrance for supplying the fluid to the fluid entrance. Preferabiy, the fiuid entrance is arranged in a centra! part of the first wall. Thus, the distance the fluid needs to travel from the fluid entrance to the spaces between the battery cells is reduced, which leads to a controlled temperature raise of the fluid.

According to an aspect of the invention, the cross-section areas of the fluid channels are clecreasing further away from the fluid entrance. The fluid channels become narrower further away from the fluid entrance. Thus, the cross-section areas of the fluid channels are decreasing towards the ends of the channels. This aspect will decrease the pressure in the channels. Aiso, the liquid fiow wili be better balanced and distributed.

According to an aspect of the invention, at least some ofthe channel's branches into a plurality of narrower channels passing at least one of the opening of the distributor piate.

According to an aspect of the invention, the channels are smoothly bent. Sharp bents are avoided. The shapes of the channels are baianced through smooth bends to avoid turbulence and to control the pressure. This aspect provides a reduced flow disturbance and minimizes the fiow resistance.

According to an aspect of the invention, the casing is provided with at least one fluid outlet, the battery comprises a coilector plate disposed between the casing and the battery cells on an opposite side of the battery cells with respect to the distributor plate, the coilector plate is provided with a plurality of openings for receiving the fluid from the spaces between the battery cells, and the battery module comprises a second manifold structure arranged between the collector plate and the at least one fiuid outlet, and the second manifoid structure comprises a plurality of second fluid channeis arranged to guide the fiuid from the openings in the coliector plate to the at least one fluid outlet.

According to an aspect of the invention, the battery comprises at least one cell holder for holding and supporting the battery ceils, and the cell hoider comprises a plurality of through holes for hoiding the battery celis and a plurality of openings disposed between the through holes to allow the fluid to pass through the cell holder. ln one aspect, the openings in the ceil holder are aiigned with the openings in the distributor plate. The cell holder ensures a minimum distance between battery cells and the openings in the ceil holder allow for fluid flow in the axial direction of the battery cells. This aspect allows the fluid to pass through the celi holder. The flow of fiuid in the spaces between the battery celis is improved and accordingiy the cooling of the battery cells is improved.

According to an aspect of the invention, the at least one cell holder is arranged at upper and/or lower ends of the battery cells. This location of the cell holders is advantageous since the cell holder will not disturb the fiuid flow along the surfaces of the battery celis. Accordingly, a laminar flow of fluid between the battery cells is achieved.

According to an aspect of the invention, the battery module comprises at least one electrical conductor adapted to provide electrical connection between a plurality of neighbouring battery cells, the electrical conductor comprise a plurality of openings aligned with the openings in the distributor plate to allow the fluid to pass through the electricai conductor.

According to an aspect, the electricaf connectors are busbars. This aspect allows the fluid to pass through the eiectrical conductor improves the cooling of the battery cells.

According to an aspect, the eiectrical connectors are a metal sheet with a plurality of openings aligned with the openings in the distributor piate to allow the fluid to pass through the electrical conductor.

According to an aspect, the eiectrical connectors are a flexifilm with printed circuits or a Printed Circuity Board with a plurality of openings aligned with the openings in the distributor piate to allow the fluid to pass through the electrical conductor.

According to an aspect, the electrical connector with a plurality of openings has a multiple function as distributor plate and the openings are aligned with the volumes between the battery cells.

According to an aspect of the invention, the first wail is a lid of the casing. Thus, the fluid channels are a part of the iid of the casing.

Brief description of the drawings The invention will now be explained more ciosely by the description of different embodiments of the invention and with reference to the appended figures.

Fig. 1 shows an example of battery module in a perspective view.

Fig. 2a shows a perspective view of an example of a stack of battery cells.

Fig. 2b shows the stack of battery cells in figure 2a from above.

Fig. 3 shows an example of a iiquid cooled module in the form of a battery module in an exploded view.

Fig. 4 shows an example of a distributor piate.

Fig. 5a-c show examples of a manifold structures inciuding channeis for distributing a fluid in views from below.

Fig. 6 shows an example of a battery module including the manifold structure shown in figure Sa.

Fig. 7 shows another example of a battery module including any of the manifold structure shown in figures 5b and 5c.

Fig. 8 shows the battery module in figure 7 from above.

Fig. 9 shows yet another example of a battery module in an expioded view.

Fig. 10 shows an example of a a celi holder for hoiding the battery cells.

Fig. 11 shows an example of an eiectrical conductors connected to the battery celis.

Figs. 12 and 13 iliustrate a restricting member.

Fig. 14 illustrates a pump inside the casing of a liquid cooled module Fig. 15 illustrates a heat sink member.

Fig. 16 is a top cross-sectional view of a iiquid cooled module.

Figs. 17 - 19 illustrate different air bubble trap arrangements.

Detailed description Aspects of the present disclosure wiil be described more fully hereinafter with reference to the accompanying drawings. ln the foilowing description a liquid cooied module with heat generating components is described. The heat generating components are in some of the exemplary embodiments set out to be battery cells. However, the heat generating components can be other types of heat generating components such as motors, electrical components, micro-processors, printed circuit boards etc. Further it is appreciated that different aspects of thermal management are described herein. it is to be understood that the different aspects can be used one by one, but also, preferably, in different combinations so as to achieve a good thermai management for the appiication at hand. Thus, even if some aspects are described in combination, the aspects can be appiied without being combined. Likewise, aspects from different examples can be combined to improve the thermal management. Like numbers in the drawings refer to like elements throughout.

Figure 1 shows an example of a iiquid cooled module 1. The liquid cooled module in the example of Figure 1 is a battery module 1 in a perspective view. A battery may include one or more battery modules electricaily and fluidicaliy connected to each other. The battery modules can be eiectrically connected to each other in series or in parailel. The battery module 1 can be used for storing and supplying electrical power to any electrical system, such as an electric vehicle, an industrial electrical system, and a stationary energy storage system. For explanatory purposes, a single battery module 1 will be explained in detaii in the description provided below.

The battery module comprises a casing 2 enclosing a stack of heat generating components 5. ln this example al! of the heat generating components are battery ceils 5. However, it is also envisaged that some or all of the beat generating components 5 could be other types of heat generating components 5. Also, not all components in the stack of heat generating components need to be heat generating, but could be of other types. ln the iliustrated embodiment, the casing 2 has a substantiaily hoilow, and rectangular configuration. The casing 2 defines a first end 2a and a second end 2b disposed opposite the first end 2a. The casing 2 may have other configurations depending on appiication requirements. The casing also defines a length extending between the first end 2a and the second end 2b. The casing comprises a plurality of walis 3a-f, such as a first wall 3a, a second wall 3b disposed opposite the first wali 3a, a first end wall 3c disposed at the first end 2a of the housing 2, a second end wail 3d disposed at the second end 2b of the housing, and a front walš 3e, and a rear wali 3f. The first and second walls 3a-b are arranged in parallel and extends between the end walis 3c-d. Tbe first wall 3a can, for example, be a lid of the casing, and the other wails defines a box-like bottom part of the casing 2. ln such case, the first wail 3a can be removably attached to the bottom part of the casing or to an end wali thereof. The casing 2 can be made of any suitable material, such as a polymer, a metal for example Aluminum an alioy (such as an Aluminum-ailoy), and the iike. The casing 2 is sealed to hold a fluid inside the casing. ln the exemplary embodiment of Figure 1, the casing 2 comprises at least one a fluid entrance 8 and at least one a fluid outlet 9. The fluid entrance 8 is an opening in the casing adapted to receive a flow of fluid into the housing 2. The fluid entrance 8 can be connected to an inlet port for the fluid. The fluid entrance is positioned between the first wall and the top level of battery cells. The casing can be provided with more than one fluid entrance 8 and more than one fluid outšet 9. The fluid outiet 9 is an opening in the casing 2 to aliow tbe fiuid to leave the casing 2. The fluid outlet 9 can be connected to an outiet port for the fluid. The fluid outlet is positioned between the second wali and the bottom level of battery celšs. The fluid entrance and outlet can be switched, so that is the liquid is entering between the second wall and the bottom ievel of battery celis and leaving between the first wašl and tbe top levei of battery celis. The fluid may be any tbermal management fluid, such as a dielectric liquid, a gas, or a combination of a liquid and a gas. ln the illustrated embodiment, the fluid entrance 8 and the fluid outiet 9 are disposed in the front wall Se. However, tbe fluid entrance 8 and the fluid 11 outlet 9 can be arranged in any of the walls 3a-e, such as in the first wall 3a and the second wall 3b respectively, or in the first and second end walls 3c-d respectively. The fluid outlet 9 is disposed spaced apart from the fluid entrance 8. ln alternative embodiments, the casing can have more than one fluid entrance 8 and more than one the fluid outlet 9 so that a plurality of battery cells can be fluidly connected to each other. The casing is also provided with two or more electric ports 10 to allow the battery module to be electrically connected to an external Circuit and/or to other battery modules. ln accordance with an alternative embodiment, no fluid entrance/inlet or outlet is provided. ln such an embodiment liquid can be pumped inside the casing and heat can be dissipated via the casing 2.

Figure 2a shows a perspective view of an example of a stack 5 of components, in this example battery cells 11. With a stack 5 is meant a plurality of components arranged in a defined configuration. ln the illustrated example, the components, here battery cells, are arranged in a hexagonal configuration. This configuration can for example be used for hexagonal battery cells. However, the components battery cells can be arranged in other configurations, such as a square configuration. This configuration can for example be used for prismatic battery cells. Figure 2b shows the stack 5 of battery cells in figure 2a from above. The battery cells 11 are arranged so that spaces 12 for housing a fluid are formed between the battery cells 11. These spaces 12 form smooth fluid volumes without inflicting structures in the way for the fluid. The spaces 12 are typically formed between envelop surfaces of the battery cells. The spaces 12 then form elongated and parallel volumes between the battery cells, without inflicting structures in the way for the liquid/fluid used to cool the battery cells. The volumes can be seen as channels running in an axial direction from one side of the battery cells to the other side of the battery cells. The liquid /fluid used to cool the battery cells can be supplied to the spaces from a direction parallel to the orientation of the spaces 12. Thus, when the cooling fluid/liquid is supplied into the spaces 12, the feed of cooling liquid/fluid is in a direction parallel to the spaces. ln Fig. 2a the liquid /fluid can be fed from above down into the elongated spaces 12 as will be described in more detail later. ln the illustrated embodiment, the battery cells 11 are cylindrical. Each of the battery cells 11 have an axis of symmetry, an envelope surface facing the spaces 12, and upper and lower ends. ln the illustratecl embodiment, the battery cells 11 are elongated and the longitudinal axes of the battery cells coincides with the axes of symmetry. The battery cells 11 are arranged with their axis of symmetry in parallel. The spaces 12 form elongated and parallel channels between the battery cells, without disturbing Structures. ln alternative embodiments, the battery cells can have other shapes, such as rectangular, e. g. prismatic cells. The battery cells can be arranged in close vicinity to each other, or at a distance from each other so that the spaces 12 surround the battery cells. The spaces 12 form elongated and parallel volumes between the battery cells, without disturbing Structures. ln one aspect, the battery cells 11 are arranged perpendicular to the first and second walls 3a-b. Also, the number or battery cells 11 shown 12 in the accompanying figure is merely exemplary and may vary based on application requirements. Thus, the Cooling liquid /fluid can run freely aiong the sides of the battery ceils 11 in the spaces 12 without any obstructing element in the way. The flow can also be in the opposite direction. For example, the flow can be from the bottom up. Thus, a fiow in the axial direction of the battery cells 12 is achieved where the flow is unobstructed. ln yet another embodiment the battery celis are iocated on both sides of the inlet/outlet of the Cooling liquid /fluid. For exampie, one or two layers of battery cells can be located above the iniet/outlet of the Cooling liquid /fiuid and one or two layers of battery cells can be iocated below the inlet/outlet of the Cooling liquid /fluid. ln other embodiments further layers can be arranged, but the Cooling efficiency wili decrease the more battery celis the Cooling liquid /fluid needs to cool before being cooled itself.

The battery cell 11 also includes one or more electric terminais to allow the battery cells to be electrically connected to each other. For exampie, the eiectric terminals are disposed at the upper ends of the battery cells. ln the illustrated example, every second of the battery cells is turned upside down so that the some of the eiectrical terminals points downwards and some of the electrical terminals points upwards. This facilitates the electricai connection of the battery celis. The battery cells 11 may be any electrochemical cell, such as a Lithium-lon type electrochemicai cell, a Lithium-Poiymer type eiectrochemicai cell, solid state batteries, and the like. ln an alternative embodiment, the battery moduie may include two or more layers of battery cells.

Figure 3 shows an example of a battery module 1 according to an embodiment in an expioded view. The battery module 1 comprises a stack 5 including a piurality of Cylindrical battery ceils 11 arranged adjacent each other so that spaces 12 for housing a fluid is formed between the battery cells. The battery module 1 further comprises a distributor plate 14 provided with a piurality of openings 15 spaced apart from each other for distributing the fluid to the spaces 12 between the battery cells 11, and a manifold structure 17 comprising a plurality of fluid channels 18 arranged to guide the fluid between the at least one fluid entrance 8 in the casing 2 and the openings 15 in the distributor plate. The distributor plate 14 can to improve the flow path of the fluid moving in the liquid cooled module. Aiso, the manifold structure 17 can act as a restricting member to improve the fiow path of the fluid moving in the liquid cooied module. The openings 15 in the distributor plate 14 are arranged to place the openings above or below regions in which the spaces 12 between the battery cells are iocated. The manifold structure 17 is arranged between the at least one fluid entrance 8 of the casing and the distributor plate 14. ln one aspect of the invention, the manifold structure 17 is integrated into the first wail 3a. ln another aspect, the manifold structure 17 is attached to the first wall 3a. Each of the fluid Channels 18 in the manifold structure 17 is in fluid communication with the one or more fluid entrances 8 of the casing 2. The openings 15 in the distributor piate are in fiuid communication with the at least one fluid entrance 8 via the fluid Channels 18. When fluid/ liquid flows in the spaces 12, the celis can be arranged so that the flow only cools one layer of cells and not muitiple serially arranged ceils. For example, one iayer of battery celis 13 11 can be arranged above the inflow of fluid/liquid and one layer of battery cells can be arranged below the inflow of fluid/liquid. Hereby, the fluid will only flow a distance of about the axial length of the battery cells before being cooled. ln this way all battery cells will be cooled equally.

The distributor plate 14 defines a plane arranged perpendicular to axes the battery cells 11. The distributor plate 14 is disposed either above the upper ends of the battery cells 11 and/or below the lower ends of the battery cells. Thus, the openings 15 in the distributor plate are either above and/or below the spaces between the battery cells so that the fluid will flow in parallel with the envelop surfaces of the battery cell in the axial directions of the battery cells 11. The positions of the plurality of openings 15 in the distributor plate 14 correspond to positions of the spaces 12. The openings 15 in the distributor plate 14 are preferably aligned with the spaces 12 between the battery cells so that the fluid enters the spaces 12 between the battery cells 11 and flows along the surfaces of the battery cells. There may also be openings aligned above the battery cell poles. ln one aspect, the manifold structure 17 comprises a plate shaped body, and the fluid channels 18 are formed in the plate shaped body. The manifold structure 17 then defines a plane perpendicular to the axes of the battery cells 11, and the plurality of fluid channels 18 are arranged so that they extend in the plane defined by the manifold structure. The manifold structure 17 can be made of any suitable material, such as a polymer, a metal, an alloy, and the lil The distributor plate 14 is disposed between the manifold structure 17 and the stack 5 of battery cells 11. ln one aspect, the distributor plate 14 is attached to the manifold structure 17. ln another aspect, the distributor plate can be integrated into the manifold structure. ln another aspect the distributor plate is combined with an electrical connector. ln one aspect, a cell holder can be arranged between the stack of battery cells and the distributor plate.

The casing 2 encloses the stack 5 of battery cells 11 and the distributor plate 14. The manifold structure 17 can be integrated in one of the first and second walls 3a-b of the casing 2. The manifold structure 17 can be integrated into a lid of the casing. The lid can, for example, be the first wall 3a. Alternatively, the manifold structure 17 can be disposed between one of the first and second walls 3a-b and the distributor plate 14. ln such case, the manifold structure 14 17 has an upper surface facing the wall 3a-b of the casing, and the manifold structure 17 can be attached to one of the first and second Walås 3a-b.

Figure 4 shows an example of a distributor piate 14 including a plurality of openings 15. The openings 15 in the distributor plate are arranged above and beiow the spaces 12 so that the flow of fluid is guided towards the spaces 12 between the battery celis. Thus, the position of the openings depehds oh the configuration of the battery cells. Preferably, the openings 15 are substantiaily eveniy spread over the distributor plate. Thus, the fluid can be evenly distributed between the battery cells. The number of openings 15 may vary in dependence of the number of battery celis 11 in the battery module. The location of the openings 15 varies in dependence of the shape and location of the battery cells and the space between them. The size and shape of the openings 15 may vary in dependence on the size and shape of the spaces 12 between the battery ceils. ln the illustrated embodiment, the openings are circular. However, the openings 15 may have other shapes, such as rectangular, triangular, or Y- shaped. The distributor plate 14 can be flexible, rigid, or semirigid. ln another aspect a combination of at least two distributor plates can be used, where one distributor plate is made of rigid material and the other(s) of flexible or semi-rigid materiai. The distributor plate 14 can be made of any suitable material, such as a polymer, a metai, an alloy, and the like. Preferably, the distributor plate is made of a fiexible material, such as EPDlVl, Neoprene, Poiyamide. ln one aspect, the distributor plate can be made of an electrically conducting material, such metal or metal alloy, flexifilm or PCB and has an additional function as electricai connector.

The manifold structure 17 including the fluid channels 18 can be designs in different ways. Figures 5a-c show three examples of different manifoid structures 17a-c. The figures 5a-c show the bottom surfaces 19 of the manifoid structures 17a-c.

Figure 5a shows a first exampie of a manifoid structure 17a in a view from below. The manifold structure 17a comprises a piurality of straight fluid channels 18a extending from the first end 2a to the second end Zb of the casing 2. Each of the fluid channels 18a has an open side facing the distributor plate 14. The open sides of the fluid channels 18a define elongated openings 20a in the bottom surface 19a of the manifold structure 17a. The elongated openings 20a are facing the distributor plate 14 and the openings 15 in the distributor plate. The elongated openings 20a extend over the openings 15 in the distributor plate from the first end 2a to the second end Zb of the casing 2 so that the openings 15 in the distributor plate are in fluid communication with the channels 18a. The distributor piate 14 can be tightly attached to the manifold structure 17a so that the parts of the elongated openings Za, which do not face the openings 15 in the distributor plate, are sealed by the distributor plate 14. The distributor piate 14 forms the bottoms of the fluid channels 18a. The elongated openings 20a in the manifold structure 18a are arranged so that they face the openings 15 in the distributor plate so that the fluid in the fluid channels 18a can leave the channels through the openings 15 in the distributor plate. ln this example, each of the elongated opening 20a in the manifold structure faces more than one of the openings 15 in the distributor plate. Thus, one fluid channel 18a supplies fluid to a plurality ofopenings 15 in the distributor píate. The upper sides of the fluid Channels 18a can be closed or open. lf the upper sides of the fluid channeis 18a are closed, the manifold structure 17a can be integrated into one of the first and second walis 3a-b. The manifoid structure 17a comprises an iniet channel 21 arranged perpendicular to the fluid channels 18a and in fluid communication with the fluid Channels 18a for supplying the fluid channels with fluid. The inlet channei 21 has an inlet opening arranged in fluid communication with the inlet entrance 8 of the casing for receiving the fluid. Alternatively, if the manifold structure is integrated into one of the walls of the casing, the inlet opening of the inlet channel 21 is the inlet entrance 8.

Figure 5b shows a second example of a manifold structure 17b in a view from below. The manifold structure 17b Comprises a plurality of fluid channels 18b. in this example, the fluid channels 18b branches into a plurality of narrower fluid Channels 18b'. The fiuid Channels 18b will become narrower closer to the ends of the fluid channels. The cross-section areas of the fluid channels 18b are decreasing further away from the fluid entrance. Each of the fluid Channels 18a has an open side facing the distributor plate 14. The open sides the fiuid Channels 18b define elongated openings 20b in the bottom surface 19b of the manifold structure 17b. The elongated openings 20b in the fluid Channels 18b faces the openings 15 in the distributor piate so that the openings 15 in the distributor plate are in fluid communication with the Channels 18b. The distributor plate 14 is attached to the manifold structure 17b so that the elongated openings 20b in the bottom surface 19 of the manifoid structure are partly seaied by the distributor plate. Each elongated opening 20b in the manifold structure faces one or more of the openings 15 in the distributor plate. The upper sides of the fiuid Channels 18b Can be closed or opened. lf the upper sides of the fluid Channels 18b are closed, the manifold structure 17b Can be integrated into one of the first and second walls 3a-b. if the upper sides of the fluid Channels 18b are opened, the manifold structure 17b can be attached to any of the first and second walls 3a-b so that the upper sides of the fluid channeis 18b are sealed by the walí of the casing. ln this example, the fluid is suppiied to a fluid channel 18b in a centra! portion of the manifold structure 17b.

Figure 5c shows a third example of a manifold structure 17c in a view from below. The manifold structure 17c Comprises a plurality of fluid channeis 18C. ln this example, the fluid channels 18C branches into a plurality of narrower fiuid channels 18c'. The fluid Channels 18b will become thinner Closer to the end of the channels. The cross-section areas of the fluid channels 18C are decreasing further away from the fluid entrance. The fluid channels 18C are smoothly bent, as seen in figure SC. The shape of the Channeis 18C is balanced through the smooth bends to avoid turbulence and to control the pressure. Sharp bents of the channels 18C are avoided. The fluid channels 18C may extend over one or more of the openings 15 in the distributor piate so that the openings 15 in the distributor plate are in fluid communication with the Channels 18c. ln one aspect, each of the branches of the fluid Channels 18C ends in one of the openings 15 in the distributor piate. 16 Each of the fluid channels 18c has an upper side facing the first wall 3a and a lower side facing the distributor plate 14. ln this example, the upper sides as well as the lower sides of the fluid channels 18c are opened. Thus, the fluid channels 18c define elongated openings 20c in the manifold structure. The upper sides of the channels 18c form elongatecl openings in a top surface of the manifold structure. The lower sides of the channels 18c are opened and form elongated openings 20c in the bottom surface 19c of the manifold structure 17c. ln one example, the manifold structure 17c is arrangecl between the distributor plate 14 and the first wall 3a. The distributor plate 14 is tightly attached to the bottom surface 19 of the manifold structure 17c so that the elongated openings 20c in the bottom surface of the manifold structure are partly sealed by the distributor plate 14. The upper surface of the manifold structure 17c is tightly attached to the first wall 3a so that the elongated openings in the top surface of the manifold structure are sealed by the first wall 3a. Thus, the first wall 3a and the distributor plate 14 seal the fluid channels 18c in the manifold structure. Thus, the fluid channels 18c are defined by the first wall 3a, the manifold structure, and the distributor plate 14. This aspect facilities manufacturing of the fluid channels.

Figure 6 shows an example of a battery module 1a including the manifold structure 17a shown in figure Sa. ln this example, the manifold structure 17a is integrated into the first walls 3a of the casing. ln this example, the fluid entrance 8 is disposed in the front wall 3e of the casing in the vicinity of the first end 2a of the casing 2. The distributor plate 14 is attached to the manifold structure 17a. The fluid enters the casing 2 through the fluid entrance 8 and is guided by the fluid channels 18a to the openings 15 in the distributor plate 14. The fluid enters the spaces 12 between the battery cells 11 and flows parallel to the axis of the battery cells along the envelop surfaces of the battery cells. The fluid exits the casing through the fluid outlet 9 at an opposite side of the stack 5 of battery cells. ln this example, the fluid outlet 9 is disposed in the front wall 3e of the casing in the vicinity of the second encl Zb of the casing.

Figure 7 shows another example of a battery module 1b including any of the manifold structure 17b-c shown in figures 5b and 5c.

Figure 8 shows the battery module lb in figure 7 from above. ln this example, the manifold structure 17l3-c is arranged between the distributor plate 14 and the first wall 3a. The distributor plate 14 is attached to the manifold structure 17b-c, and the manifold structure 17b-c is attached to the first wall 3a. ln this example, the fluid entrance 8' is arranged in a central portion of the first wall 3a at a distance from the edges 4 of the first Wall 3a, and the first wall 3a is provided with an inlet channel 22 arranged between one edge 4a of the first wall 3a and the fluid entrance 8' for supplying the fluid to the fluid entrance 8', as shown in figure 8. An inlet port 23 is connected to the fluid entrance 8'. The second wall 3b of the casing is provided with a fluid outlet 9' for the fluid. The second fluid outlet 9' is arranged in a central portion of the second wall Bb at a distance from the edges of the second wall 3b. The fluid enters the casing 2 through the fluid entrance 8' and is guided by the fluid channels 18b-c to 17 the openings 15 in the distributor plate 14. The fluid enters the spaces 12 between the battery cells and flows parallel to the axis of the battery cells 11 along the envelop surfaces of the battery cells. The fluid exits the casing 2 through the fluid outlet 9' at the opposite side of the stack 5 of battery cells 11, as shown in figure 7.

Figure 9 shows yet another example of a battery module 1c. The battery module 1c differs from the battery module lb disclosed in figure 3 and 7 in that the battery comprises a collector plate 24 disposed between the second wall 3b and the stack 5 of battery cells on an opposite side of the stack 5 of battery cells with respect to the distributor plate 14. The collector plate 24 is provided with a plurality of openings 15' for receiving the fluid from the spaces 12 between the battery cells 11. The openings 15' ofthe collector plate 24 are preferably aligned with the openings 15 of the distributor plate 14. Preferably, the collector plate 24 is designed in the same way as the distributor plate 14. The battery module lc further comprises a second manifold structure 17' arranged between the collector plate 24 and the fluid outlet 9. The second manifold structure 17' comprises a plurality of second fluid channels 12' arranged for guiding the fluid from the openings 15' in the collector plate 24 to the fluid outlet 9 in the second wall 3b. The second manifold structure 17' is, for example, any of the manifold structures 17a-c shown in figures 5a-c.

The battery module may also comprise one or more cell holders for holding the battery cells 11 in their positions relative each other. The cell holder ensures a minimum distance between battery cells allowing a fluid flow along the envelop surfaces of the battery cells 11 in a direction parallel with the symmetry axes of the battery cells. The holder also ensures a minimum distance to avoid short circuit.

Figure 10 shows an example of a cell holder 26. The cell holder 26 comprises a plurality of through holes 28 for receiving the battery cells 11 and a plurality of openings 30 disposed between the through holes 28 to allow the fluid to pass through the cell holder 26. Preferably, the plurality of openings 30 are aligned with the openings 15 in the distributor plate 14. Suitably, the openings 30 correspond to and have the same shape and positions as the openings 15 in the distributor plate. The cell holder 26 is disposed in the casing 2 and is adapted to receive and support the battery cells 11 in the stack 5 within the casing. ln one embodiment, the battery module comprises two cell holders 26. One of the cell holders 26 is disposed at the top of the stacl< of battery cells, and the other cell holder is disposed at the bottom of the stack 5 of battery cells. This location of the cell holders is advantageous since the cell holders will not disturb the fluid flow along the surfaces of the battery cells. Accordingly, a laminar flow of fluid between the battery cells is achieved. The cell holder 26 can be made of any suitable material, such as a polymer, a metal, an alloy, and the like. Also, in some embodiments the cell holder 26 can be formed by the distributor plate 14. 18 The battery cells 11 in the stack 5 are electrically connected to each other. ln one embodiment, each of the battery cells may be electrically connected to each other in a series configuration. ln yet other embodiments, each of the battery cells may be electrically connected to each other in a parallel configuration, based on application requirements. The battery module comprises one or more electrical conductors, such as busbars, adapted to provide electrical connection between adjacent battery cells. Each of the battery cells is provided with poles for connection to the electrical conductor.

Figure 11 shows an example of battery cells 11 electrically connected to each other by means of an electrical conductor 32 connected to the battery cells. ln the illustrated example, the electrical conductor 32 is a busbar. The electrical conductor 32 is adapted to provide electrical connection between a plurality of neighbouring battery cells. The electrical conductor 32 is in electrical contact with the poles ofthe plurality of neighbouring battery cells 11. The electrical conductor 32 comprise a plurality of openings 43 to allow the fluid to pass through the electrical conductor. Preferably, the openings 43 in the electricals connector 32 are aligned with the openings 15 in the distributor plate. The battery module may comprise one or more electrical conductors 32. The electrical conductor 32 can be arranged on top of and/or below the battery cells 11. The electrical conductor 32 may be made of any electrically conductive material, such as a metal, an alloy, and the like. For example, the electrical conductor 32 is a metal foil, or a laminate of polymer and electric wirings. The electrical conductor 32 can also be connected to the one or more electric ports 10. For example, the distributor plate 14 can be made of an electrically conducting material and be used as the electrical conductor 32. lh one aspect, the electrical conductor 32 is the distributor plate 14. ln order to improve the liquid cooling, the liquid flow inside the liquid cooled module 1;1a;1b;1c can comprise restricting members in the spaces 12 formed between the heat generating components 11. This is shown in Fig. 12. ln Fig. 12 restricting members in the form of elongated elements 160 are shown located in the spaces 12 formed between cylindrical heat generating components 11. The restricting members in the spaces 12 can have multiple purposes. For example, by locating a restricting member 160 between cylindrical heat generating components 11, the liquid flow around the cylindrical heat generating components can be improved in that the liquid is forced to have its main flow closer to the heat generating component 11 and thereby improve the heat dissipation from the heat generating component. While the restricting members 160 are located in the spaces 12 they are not obstructing the axial flow along the sides of the battery cells 12. The restricting members will instead re-distribute the flow around the heat generating components 12. ln other words, the restricting members 160 will re-configure the shape of the spaces 12 so the flow Channels formed in the spaces 12 will have another shape. There will still be an axial path that is unobstructed to support a free flow of the colling liquid/fluid used to cool the heat generating components 12. Thus, the shape of the flow 19 channels in the spaces 12 can in this way be changed. The fiuid is then moved in an axial direction in fluid channels formed in the spaces (12). The length of the fiuid channels then corresponds to the axial length of the heat generating components. ln other embodiments the fluid channeis extend almost the length of the heat generating components such as at least 80% of the length of the heat generating components.

The restricting members 160 can also serve as an electric isolator and be made from an isoiating material. The restricting member can also serve as a distance member to keep the heat generating components in piace at a desired iocation.

Further, the restricting members 160 can serve as a compensatíng member to enable thermal expansion of the heat generating components 11. ln Fig. 13 an exemplary restricting member 160 is shown. The restricting member 160 of Fig. 13 is generally cyiindrical in shape and can be said to be pin shaped. By providing a hollow section inside the restricting member 160 the restricting member 160 can be made to at least partialiy coliapse to compensate for thermal expansion of the heat generating components 11 when the restricting member 160 is iocated in the spaces 12 between the heat generating components. Fig. 13 shows such a collapsed restricting member 161.

As shown in Fig. 13, the restricting members 160 can be generally cylindrical in shape. This can be particuiarly advantageous when the restricting members are located in spaces between cylindrical heat generating components. However, other shapes of the restricting members 160 can also be used. For example, semi-cylindricai shapes of the restricting members 160 can be used or prismatic shaped restricting members can be used. ln other embodiments partiai cylinders other than semi-cylinders can be used such as quarter cylinders or other types of cut cylinders or prisms. The restricting members can advantageously have the same axial length as the heat generating components 11.

Depending on the purpose of the restricting member 160 the material can be selected accordingiy. For example, in accordance with some embodiments, the restricting members are formed by an elastic material. This can be useful when the restricting member should serve as a thermal expansion compensator. The restricting members can also be formed by an electric conductive materiai to aid in conducting electricity or the restricting members can be formed by an electrically isolating material to form an isolating member. ln accordance with some embodiments the pump for generating a flow inside the liquid cooled module can be located inside the liquid cooied module. ln particular the pump for pumping the fluid is iocated inside the liquid sealed casing. The pump can advantageously be an Electrohydrodynamic (EHD) pump. However other types of pumps are also envisaged such as a mechanical pump, a magnetohydrodynamic pump, a centrifugal pump, an osmotic pump, a sound wave pump, a diaphragm pump, a piezoelectric pump, a peristaltic pump, a nozzle-diffuser pump, a tesla pump, a capillary pump or similar. The pump can be cylindrical in shape. ln Fig. 14 a pump 111 is shown located inside a liquid sealed casing 2. The pump can pump liquid towards or away from a heat absorbing structure. The heat absorbing structure can be a wall in the liquid cooled module. ln particular the heat absorbing structure can be side wall of the liquid sealed casing 2 as is shown in Flg. 14. The side wall can be provided with fins or flanges or can have some other irregular shape or protrusions to enhance heat transfer. For example, the side wall can have a wicl ln accordance with some embodiments at least one partiy cylindrical, in particular a semi cylindrical heat sink member 118 is provided located on a side wall of the casing 2 or at the bottom of the casing 2. Such an at least one partly cylindrical heat sink member 118 can be provided with a flange or flanges or some other type of protrudlng member. An exemplary heat sink member 118 is shown in a cross-sectional view in Fig. 15.

Other modifications to improve the working of the liquid cooled module as described herein can also be made. For example, the liquid cooled module can comprise at least one at least heater element. The heater element can be made to generate heat during for example a start phase. The heater element can be cylindrical or semi cylindrical. ln Flg. 16 a cross-sectional top view of a liquid cooled module 1 a described above is shown. The heat generating components 11 can house different kinds of components including but not limited to battery cells, motors, pumps heat generators. ln the spaces between the heat generating components flow restricting members 160 can be located. The heat generatlng components 11 can be cylindrical as shown in Fig. 16, but could have other shapes such as a prismatic shape. There can also be components not having a cylindrical or prismatic shape. in some embodiments cut elements such as cut cylinders or prisms are located inside the liquid cooled module 1. The elements can for example be semi or quarter cylinders or prisms. The cut elements can house different components such as motor or heaters, but could also be heat sink members or thermaliy compensating structures. ln Fig. 16 cut elements are exemplified by heat sink members 118, but they could form other types of elements as described above. The cut elements 118 can typicaliy be located at the rim of the liquid cooled casing 2 to mal 21 Also, the cut elements 118 can be used to improve the flow inside the casing 2. The cut elements can then be part ofthe casing and shaped to improve the liquid flow inside the casing 2. ln order to further improve the efficiency of the liquid cooled module 1 as described herein a bubble trap arrangement can be added to remove air from the liquid flowing inside the liquid cooled module. ln Fig. 17, a bubble trap arrangement 170 is shown for a liquid cooled module 1 without an inlet/outlet. The bubble trap arrangement can also be used when the liquid cooled module 1 is provided with a liquid inlet and a liquid outlet as is shown in Fig. 18.

The bubble trap arrangement 170 can be of different types. ln Fig. 19, a bubble trap arrangernent 180 of a different l While the module as described herein is typically liquid cooled, it is also envisaged that a gas is used instead of a liquid to transport heat within the module. ln such an embodiment where the fluid is gas instead of a liquid, the fluid is in gas form and moved by at least one silent ion- wind-based pump. The module can then comprise at least one silent ion-wind enhanced flanged heat sink structure on the external casing walls.

The present invention is not limited to the embodiments disclosed but may be varied and modified within the scope of the following claims. For example, the flow channels can be designed in different ways. The liquid cooled module is advantageous for cooling many types of heat generating components. Also, different embodiments can be combined to enhance the cooling capacity of the liquid cooled module or to meet other needs such as making the liquid cooled module lighter or smaller. For example, the liquid cooled module may comprise two or more distributor plates arranged on top of each other. Different aspects of the embodiments disclosed can be combined with each other. For example, the distributor plate can be an integrated in the manifold structure so that the manifold structure and the distributor plate can be manufactured in one piece. For example, the electrical conductor may function as distributor plate. Also, the distributor plate can have flanges or funnels to increase Cooling and or to enhance distribution of liquid.

Claims (19)

1. A liquid cooled moduie (1;1a;1b;1c) comprising: - a plurality of heat generating components (11) arranged so that spaces (12) for housing a moving fluid are formed around the heat generating components, - a liquid sealed casing (2) enciosing the heat generating components (11), wherein at least one restricting member (14, 17,160) located in the flow path of the moving fluid.

2. The liquid cooied module according to claim 1, wherein the fluid is moved in an axial direction in fluid channels formed in the spaces (12) and where no inflicting structures are located in the way for the axial flow of the fluid.

3. The liquid cooled module according to claim 1 or 2, wherein a pump for pumping the fluid is iocated inside the iiquid sealed casing.

4. The Electrohydrodynamic (EHD) pump. liquid cooled module according to ciaim 3, wherein the pump is an

5. The liquid cooled module according to claim 3 or 4, wherein the pump is cylindrical in shape.

6. The liquid cooled moduie according to any one of claims 1 - 5, wherein the at least one restricting member is pin shaped and located in said spaces (12).

7. The iiquid cooled module according to any one of claims 1 - 6, further comprising a distributor plate (14) disposed between the casing (2) and the heat generating components (11) the distributor plate being provided with a plurality of openings (15) for clistributing the fluid to the spaces (12) between the heat generating components and a manifold structure (17;17a;17b;17c) comprising a plurality of fluid channels (18;18a;18b;18c) arranged between the at least one fluid entrance (8;8') and a distributor plate (14) to guide the fluid from the at least one fluid entrance (8;8') to the openings (15) in the distributor plate.

8. The liquid cooled module according to claim 7, wherein each of the fluid channels (18;18a;18b;18c) has an open side facing the distributor piate (14), and the distributor plate is tightly attached to the manifold structure (17;l7a;17b;17c) so that the open sides of the channels are partly sealed by the distributor piate.

9. The liquid cooled module according to claim 7 or 8, wherein the distributor plate is made of an electricaily conducting material and is configured to act as an eiectrical connector.

10. The liquid cooled module according to any one of ciaims 1 - 9, further comprisihg at least one at least partly cylindrical shaped thermal expansion compensating structure.

11. The liquid cooled module according to any one of ciaims 1 - 10, wherein the restricting members are formed by an elastic material.

12. The liquid cooled module according to any one of claims 1 - 11, wherein the restricting members are formed by an electric conductive material.

13. The liquid cooled module according to any one of claims 1 - 12, wherein the liquid sealed casing comprises flanges and or at least one corrugated section.

14.The liquid cooied module according to any one of ciaims 1 - 13, further comprising at least one partly cylindrical heat sink member located on a wall of the casing or at the bottom of the casing, wherein the at least one partly cylindrical heat sink member is provided with at least one flange.

15. The liquid cooled module according to any one of claims 1 - 14, wherein the at least one restricting member comprise a hollow section allowing compression of the restricting members.

16. The liquid cooled module according to any one of claims 1 - 15, wherein the at least one restricting member is formed by an electrically isolating material.

17. The iiquid cooied moduie according to any one of ciaims 1 - 16, wherein the plurality of heat generating components (11) are cylindrical in shape.

18.The liquid cooled module according to any one of claims 1 - 17, when a manifold structure (17;17a;17b;17c) is provided and where the manifold (17;17a;17b;17c) is an integrated part of the casing (2).

19. The liquid cooled module according to any one of claims 1 - 19, wherein the fluid is moved in an axial direction in fluid channels formed in the spaces (12) and where the length of the fluid channels correspond to the axial length of the heat generating components.