Temperature control device for battery module

Abstract

The invention relates to a temperature control device for a battery module (5). In addition to a temperature control circuit (50) having multiple channels in thermal contact with battery cells and a heat exchanger, the temperature control device also includes a pump (1). The pump (1) includes a spindle housing (10) and at least one screw spindle (2a, 2b), which is coupled to a dry rotor type electric motor (3).

Description

Technical Field

[0001] The present invention relates to a temperature control device for a battery storage module, for example, a battery storage module in a power battery of an electric vehicle. Background Art

[0002] The temperature control of the battery storage modules is particularly useful for dissipating the waste heat generated during the charging or consumption process by means of a temperature control medium via a heat exchanger.

[0003] The cooling circuits of pure electric vehicles are very complex with numerous line branches, fluid connections and various pumps and valves. The division of the channel cross section of the entire cooling circuit into line branches, such as a network of cooling channels (possibly capillaries) with correspondingly smaller channel cross sections, requires significantly higher delivery pressures than in the relatively large-volume cooling circuits of internal combustion engines. This structure of branched cooling circuits occurs to an even greater extent in the construction of battery storage modules, in which a large number of battery cells are cooled via small channels. Summary of the invention

[0004] The object of the present invention is to provide an alternative technique for controlling the temperature of a battery storage module having a branched temperature control loop.

[0005] A further aspect of the present object is to provide a corresponding technical solution so that it can also be produced in large quantities and cheaply through large-scale production.

[0006] According to the invention, this object is achieved by a temperature control device for a battery storage module. The temperature control device for a battery storage module is characterized in particular in that a pump of the temperature control device comprises a spindle housing having an inlet opening and an outlet opening; and at least one screw spindle rotatably accommodated in the spindle housing and coupled to an electric motor; wherein the electric motor is in the form of a dry runner and is arranged in a defined manner relative to the spindle housing.

[0007] The temperature control device according to the invention allows a delivery pressure in the temperature control circuit that is higher than that which can be achieved with a centrifugal pump. Compared to a centrifugal pump, the pump of the temperature control device according to the invention can achieve a higher delivery pressure in a cooling circuit or a temperature control circuit with line branching and corresponding restrictions.

[0008] In the case of coolant pumps of the centrifugal type, the axial gap between the impeller and the pump chamber constitutes the greatest weak point for sealing between the suction side and the pressure side of the pump. At higher delivery pressures, leakage at the axial gap and the corresponding loss of delivery performance increase. The adjustment of the gap size for the purpose of effective sealing depends on the dimensional stability of the axial fit between the impeller and the housing after assembly. When producing centrifugal pumps for higher delivery pressures, the expenditure and costs for ensuring a suitable axial sealing gap reach the limit of economic feasibility. If this is not the case, the volumetric efficiency at higher delivery pressures would be adversely affected.

[0009] In the case of the screw spindle mechanism of the temperature control device according to the invention, the effective sealing gap extends over the entire length of the screw spindle between the suction side and the pressure side. Since the screw spindle is pressed against the running surface of the suction side during operation, it is not necessary to maintain the axial gap size.

[0010] Furthermore, compared to a centrifugal pump, the screw spindle mechanism of the temperature control device according to the invention comprises a smaller acoustically active surface relative to the surrounding housing. The rotational movement of the impeller blades generates rotational pressure fluctuations at the chamber wall of the pump chamber that are dependent on the rotational speed, which pressure fluctuations may be within the resonance frequency range of the housing components.

[0011] Alternative types of displacement pumps, such as vane pumps or rotary piston pumps, generate pressure-side pulsations due to the displacement process, which cause considerable oscillations in the inlet of the temperature control circuit. Independently of the acoustic frequency, there is an attempt to keep the vibrations of the battery storage module as low as possible, thereby avoiding fatigue damage at the many contact points and welds of the conductor structure between the individual battery cells.

[0012] In contrast, the rotational movement of the screw spindle produces a relatively simple conveying action. Thus, the pump according to the invention for a temperature control device for a battery storage module ensures a low noise development level, in particular in combination with a cavity in the temperature control device for accommodating battery cells.

[0013] Although screw pumps are known in the prior art, they have hitherto been used in different types of configurations and applications.

[0014] The screw pump consists of a robust rotary piston mechanism which is insensitive to dirt and does not require delicate elements such as shut-off valves for operation. Volume adjustment is not possible relative to the preset rotational speed. Mechanically driven screw pumps are mostly used in large applications, such as oil pumps in stationary installations or ship engines, where they operate at a relatively stable operating point.

[0015] In the field of fuel delivery pumps for vehicles, smaller electrically driven screw pumps have recently become known. The electric drive of such fuel delivery pumps is designed as a wet-running electric motor without a separator tank, so that both the rotor and the stator are in contact with the fuel.

[0016] Thus, US 2018 / 0216614 A1 describes a screw pump which is configured as a fuel pump. A cover with an axial outlet is attached to the housing of the screw pump. The motor is received in an outlet chamber of the cover, through which the fuel flows before leaving the outlet.

[0017] DE 10 2015 101 443 B3 describes a fuel pump having a housing, in which an electric drive motor is coupled to a screw pump. The fuel flows through the drive motor before leaving the pressure-side outlet.

[0018] WO 2014 / 138519 A1 discloses a screw-type electric liquid pump. The liquid flowing through the inlet and the outlet also surrounds the motor. The fuel is referred to as the liquid.

[0019] DE 10 2017 210 771 A1 discloses an electrically driven screw pump as a fuel delivery component. The pump housing and the electric motor are received in the housing. In the illustrated embodiment, the solution does not include a separator pot on the stator of the electric motor, and the electric components of the motor are in direct contact with the fuel in the outlet guide plate on the pressure side of the spindle chamber.

[0020] However, known screw fuel pumps cannot be converted to pumps for use as temperature control devices for battery storage modules according to the present invention. Compared to oil-based fuels, water-based temperature control media or coolants can corrode and damage exposed parts of wet-running electric motors, such as stator coil windings.

[0021] The present invention provides a temperature control device for a battery storage module for the first time, the device having a screw spindle mechanism for conveying a temperature control medium. The present invention further provides a dry-running motor for driving the spindle mechanism. The temperature control device is suitable for conveying corrosive temperature control media.

[0022] Advantageous developments of the invention are provided in the accompanying claims.

[0023] According to one aspect of the invention, the driven screw spindle and the linked screw spindle can be mounted in a floating manner and can be axially moved inside the spindle housing by means of a radial clearance fit. In this way, an effective radial sealing gap is automatically generated between the screw spindle and the spindle housing to prevent leakage. The formation of the axial sealing gap is not affected by manufacturing tolerances. It is not necessary to maintain an axial gap size at the opposite end of the screw spindle. As a result, cost-effective large-scale production is greatly facilitated.

[0024] According to one aspect of the invention, the temperature control device can also include a plug-in connector with axial freedom, which is arranged between the shaft of the electric motor and the driven screw spindle. By using a plug-in connector that allows at least axial play, impairment of the clearance fit for the floating mounting of the driven screw spindle can be minimized. In addition, an interface for the coupling of shafts of different electric motors is created, making a modular drive concept for the temperature control device possible.

[0025] According to one aspect of the present invention, the temperature control device may further include a housing, the housing including an open cavity and a flow delivery pipeline and a return pipeline of the temperature control circuit, both of which are connected to the open cavity. Therefore, the spindle housing can be inserted into the open cavity from the axial end to the housing flange, and the temperature control circuit can be connected to the inlet opening and the outlet opening of the spindle housing.

[0026] This form provides a structural integration between the pump-side housing and the housing part of the temperature control device. Therefore, hose connections or fluid connections at the interface between the pump and the supply flow and return flow of the temperature control circuit can be omitted, and the corresponding installation space for them in the temperature control device can be saved.

[0027] The open cavity surrounding the receiving chamber of the spindle housing is used as the outlet chamber of the pump. During the construction of the receiving housing of the temperature control device, there is thus 360° of freedom for the radial arrangement of the return line of the pump. Thus, an arrangement can be selected that is optimized for the smallest possible installation space.

[0028] On one side, the pump has a pump head that can be inserted into the cavity, which has the same shape as the spindle housing, and on the other side there is a motor housing located outside the cavity. Despite the integrated construction, it is possible to use motors of different sizes.

[0029] According to one aspect of the present invention, the housing flange arranged between the spindle housing and the motor housing may include a bearing seat for a bearing, the bearing seat extending toward one side of the motor housing. This structure makes it possible to use a single shaft bearing and helps to achieve a compact axial size of the pump in the temperature control device.

[0030] According to one aspect of the invention, the spindle housing can be delimited in the region of the inlet opening by a guide key inserted through a radial assembly gap. The installation and insertion of the screw spindle is simplified by the formation of a guide key, which can be formed in a simplified manner as a bearing shield with an inlet opening.

[0031] According to one aspect of the invention, the shaft of the electric motor can be mounted by means of a bearing with a sliding bearing bushing, and the sliding bearing bushing can be surrounded by a sealingly filled lubricant. This formation allows the bearing of the shaft to be compact and durable. The sealing lubrication of the sliding bearing bushing resists any scouring or precipitation of the temperature control medium. Compared with oil-based media to be conveyed, such as lubricating oil or fuel, the contact between the sliding bearing and the temperature control medium can have an adverse effect on the sliding properties of the bearing. In addition, the sealing filling of the lubricant, together with the sliding bearing gap of the sliding bearing bushing, ensures a special sealing function. A good and lasting sealing function is highly relevant to the service life of the pump and the operating safety of the battery storage module to be temperature controlled, especially when operating with higher delivery pressures on the one hand and using dry-running electric motors on the other hand.

[0032] According to one aspect of the invention, the power electronics may be arranged within the interior of the motor housing in thermal contact with the housing flange. The housing flange is in contact and in heat exchange relationship with the spindle housing and the containment housing through which the coolant of the temperature control circuit flows. The arrangement of the power electronics in thermal contact with the housing flange provides an effective structure for transferring waste heat from the power electronics of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of a temperature control loop according to an embodiment of the present invention and a cross-sectional view of a screw spindle mechanism of a temperature control device for a battery storage module are shown. DETAILED DESCRIPTION

[0034] For the purposes of this disclosure, the term "temperature control circuit" is understood to mean a conveying circuit for a temperature-controlled medium. The medium to be conveyed may be a water-based coolant with additives such as glycol or other antifreeze agents. The operating mode of the temperature control circuit is not limited to a cooling function. Thus, for example, during the start-up phase of the system or when the ambient temperature is low, the temperature control circuit may also provide a heating function using a heat source.

[0035] The "supply line" and "return line" of the temperature control loop refer to how the battery storage module whose temperature is to be controlled is viewed. Thus, the supply line of the temperature control loop is connected to the outlet opening of the pump and the return line of the temperature control loop is connected to the inlet opening of the pump.

[0036] In the temperature control loop, multiple battery storage modules can be connected so that the flow passes through them in parallel or in series. In addition, the temperature control loop can connect multiple temperature control devices and multiple pumps.

[0037] The term "temperature control source" for the purposes of the present disclosure relates to the atmosphere or convective airflow of the system environment, to a cold source with a coolant or a hot source, such as an electric heating element. The corresponding temperature control source is in thermal contact with the temperature control medium in the temperature control circuit via a heat exchanger, such as a finned radiator or the like.

[0038] For the purposes of this disclosure, the term "screw pump" is understood to be an oblique rotary piston pump with a pitch for displacement of the medium to be conveyed. Pumps of this type usually include a driven screw spindle and at least one further screw spindle coupled thereto via a toothed engagement.

[0039] exist Figure 1 In the case of the temperature control device shown, the pump 1 is arranged in an integrated manner in the temperature control circuit 50. The temperature control circuit 50 is used to control the temperature of the battery storage module 5, in particular to discharge the waste heat generated during charging or consumption via a heat exchanger (not shown) by means of a temperature control medium delivered by the pump 1. In the following application, the battery storage module 5, which is not shown in detail, is a power battery for a pure electric vehicle. The temperature control circuit 50 includes a plurality of channels with a small cross section, which are in thermal contact with a plurality of battery cells of the battery storage module 5.

[0040] exist Figure 1 In the embodiment of the schematic diagram of the pump 1, in the spindle housing 10, the driven screw spindle 2a and the linked screw spindle 2b are rotatably received in the spindle chamber 12 of the spindle housing 10. The cross-sectional profile of the spindle chamber 12 is formed by two holes in the spindle housing 10, whose radii overlap to ensure the meshing of the screw spindles 2a and 2b. The open side of the spindle chamber 12 is defined by a guide key 18. The guide key 18 is formed flatly as the end surface chamber wall of the spindle chamber 12 and has an inlet opening 16 of the spindle housing 10. The guide key 18 is inserted into the spindle housing 10 through a mounting groove perpendicular to the screw spindles 2a and 2b.

[0041] The screw spindles 2a, 2b are mounted in a floating manner by radial clearance fit relative to the cross-sectional profile of the spindle chamber 12 and axial clearance fit of the spindle chamber 12. During operation of the pump, the spindles are pressed against the guide key 18 by a displacement process. The guide key 18 acts as a bearing shield of the axial sliding bearing relative to the end surface of the screw spindles 2a, 2b.

[0042] The pressure side of the spindle chamber 12, which is connected to the outlet opening 17 of the spindle housing 10, is located on the drive side of the screw spindle 2a, 2b, which side is described as being on the right side. The suction side of the spindle chamber 12 is located on the other side of the screw spindle 2a, 2b, on which the guide key 18 is arranged. The suction side of the spindle chamber 12 is connected to the inlet opening 17 of the spindle housing 10.

[0043] The spindle housing 10 and the screw spindles 2a, 2b form an insertable pump head which is inserted from the axial end of the spindle housing 10 into a housing 15 of the temperature control device, with the inlet opening 16 facing the housing, as far as the housing flange 14 connected to the opposite axial end of the spindle housing 10. The housing 15 is an integral component of the temperature control device, the pump 1 and the temperature control circuit 50. The housing 15 can also be an integral component of the module housing of the battery storage module 5, in which the temperature control circuit 50 continues to exist in the form of an integrated channel.

[0044] The containment housing 15 includes an open cavity 11, which receives the spindle housing 10 up to the housing flange 14. The return flow line 56 and the delivery flow line 57 of the temperature control circuit 50 lead into the cavity 11. The delivery flow line 57 opens to the peripheral surface of the cavity 11. The cavity 11 surrounds the spindle housing 10, so that an annular portion of the cavity 11 is exposed where it overlaps with the outlet opening 17 and the mouth of the delivery flow line 57. The exposed portion of the cavity 11 creates a pressure-side connection between the spindle housing 10 and the temperature control circuit 50.

[0045] The return line 56 leads to the end-face base surface of the open cavity 11 and is distributed in a relative arrangement to the inlet opening 16 of the axial end of the inserted spindle housing 10. The sealing element 4 surrounds the mouth of the return line 56 and the inlet mouth 16, so that a suction-side connection is produced between the temperature control circuit 50 and the spindle housing 10. The sealing element 4 further surrounds the periphery of the spindle housing 10 in the area of ​​the assembly groove, through which the guide key 18 is introduced. Therefore, possible leakage flows are sealed along the insertion fit of the guide key 18. In the exposed cavity 11, the sealing ring 19 is introduced into the groove-shaped radial free space upstream of the housing flange 14 in order to seal the pressure side of the pump 1 to the outside.

[0046] The driven screw spindle 2a is connected to the motor 3. On the pressure side of the spindle chamber 12, the spindle housing 10 includes a hole for a shaft 32, which is driven by the motor 3. On the opposite side of the housing flange 14, the motor housing 13 is connected, and the motor 3 is arranged in the motor housing 13. The inner stator 33 of the motor 3 is located on the protruding ring part of the housing flange 14. The outer barrel rotor 35 surrounds the stator 33 and is connected to one end of the shaft 32. The bearing seat for the bearing 31 is formed internally on the protruding ring part of the housing flange 14. The bearing 31 is a sliding bearing, which is sealed at both axial ends and filled with lubricant. The other end of the shaft 32 is connected to the driven screw spindle 2a by means of an insertion connector 23 that allows axial clearance.

[0047] The motor housing 13 comprises a separate motor chamber in which the dry-running electric motor 3 and the electronic system, in particular the power electronics 34 for switching the electric power at the electric motor 3, are received. The stator 33 comprises field coils which are activated by the power electronics 34 and which are supplied with electric power. The stator 33 is in thermal contact with the peripheral surface of the protruding ring portion of the housing flange 14. Thus, the waste heat from the field coils of the stator 33 is transferred via the housing flange 14 to the containing housing 15 and the spindle housing 10 and is absorbed by the temperature control circuit passing through them. The power electronics 34 are also in thermal contact with the end surface of the housing flange 14, thereby discharging the waste heat of the electronic components into the area of ​​the temperature control circuit through which there is a flow.

[0048] Considered here is the conveying direction of the temperature control device in the temperature control circuit 50 in order to control the temperature of the battery storage module 5. The liquid medium to be conveyed is sucked from the return line 56 of the temperature control circuit 50 through the seal 4 and the inlet opening 16 of the spindle housing 10 on the suction side into the spindle chamber 12. The rotary movement of the meshing screw profiles of the rotating screw spindles 2a, 2b generates a negative pressure on the suction side of the spindle chamber 12 and a positive pressure on the opposite pressure side of the spindle chamber 12. The temperature control medium is conveyed by the continuous displacement of the pitch along the meshing screw profile and is ejected from the spindle chamber 12 through the outlet opening 17 of the spindle housing 10. Downstream of the outlet opening 17, the temperature control medium flows via the cavity 11 into the delivery line 57 of the temperature control circuit 50 and into the battery storage module 5.

[0049] Thereafter, the temperature control medium in the battery storage module 5 flows through the branching arrangement of channels of the temperature control loop 50, which are formed in the housing 15 of the temperature control device and are in thermal contact with the battery cells of the battery storage module 5. The temperature control medium then flows through the heat exchanger, discharges the waste heat absorbed by the battery cells of the battery storage module 5 into a cooler medium, such as ambient air, and is sucked back into the pump 1. The flow can also be in the reverse order through the battery storage module 5 and the heat exchanger in the temperature control loop 50. Furthermore, the temperature control device 50 can also additionally have a further temperature control source, such as a heating element, through which the temperature control loop 50 passes.

[0050] Reference numerals list

[0051] 1 Pump

[0052] 2a Driven screw spindle

[0053] 2b Linked screw spindle

[0054] 3. Electric Motor

[0055] 4 Seals

[0056] 5 Battery storage module

[0057] 10 Spindle housing

[0058] 11 Cavity

[0059] 12 Spindle Room

[0060] 13 Motor housing

[0061] 14 Housing flange

[0062] 15 Housing

[0063] 16 Entrance opening

[0064] 17 Exit opening

[0065] 18 Guide key

[0066] 19 Sealing ring

[0067] 23 Plug-in connector

[0068] 31 Bearings

[0069] 32 Axis

[0070] 33 Stator

[0071] 34 Power electronics

[0072] 35 Rotor

[0073] 50 Temperature control loop

[0074] 56 Return line

[0075] 57 Delivery pipeline

Claims

1. A temperature control device for a battery storage module (5), comprising: A temperature control circuit (50), the temperature control circuit (50) being configured to control the temperature of a plurality of battery cells in the battery storage module (5); in The temperature control circuit (50) transports a temperature control medium and includes a plurality of channels in thermal contact with the battery cells; a heat exchanger establishing thermal contact between the temperature control medium and a temperature control source; It is characterized in that The pump (1) for conveying the temperature control medium of the temperature control device comprises: a spindle housing (10) having an inlet opening (16) and an outlet opening (17); and at least one screw spindle (2a, 2b), the at least one screw spindle (2a, 2b) being rotatably accommodated in the spindle housing (10) and connected to the motor (3); wherein the electric motor (3) is in the form of a dry-running electric motor and is arranged in a defined manner to the spindle housing (10); The temperature control device further comprises a housing (15), the housing (15) comprising an open cavity (11) and a flow delivery pipeline (57) and a return pipeline (56) of the temperature control circuit (50), the flow delivery pipeline (57) and the return pipeline (56) leading into the open cavity (11); wherein the spindle housing (10) is configured to be inserted into the open cavity (11) from the axial end of the spindle housing to the housing flange (14), and the temperature control circuit (50) is configured to be connected to the inlet opening (16) and the outlet opening (17) of the spindle housing (10); wherein the pump has a pump head having the same shape as the spindle housing, the pump head being configured to be inserted into the open cavity; The delivery pipeline leads into the peripheral surface of the open cavity of the accommodating shell, the return pipeline leads into the end base surface of the open cavity of the accommodating shell, and the return pipeline is distributed to the inlet opening at the axial end of the spindle housing.

2. The temperature control device according to claim 1, characterized in that: The driven screw spindle (2a) and the linked screw spindle (2b) are mounted in a floating manner and can move axially inside the spindle housing (10) by means of a radial clearance fit.

3. The temperature control device according to claim 2, characterized in that: Further includes A plug-in connector (23) having an axial degree of freedom is arranged between the shaft (32) of the electric motor (3) and the driven screw spindle (2a).

4. The temperature control device according to claim 1, characterized in that: A housing flange (14) is arranged between the spindle housing (10) and the motor housing (13), wherein the housing flange (14) comprises a bearing seat for a bearing (31), the bearing seat extending toward a side of the motor housing (13).

5. The temperature control device according to claim 1, characterized in that: The spindle housing (10) is delimited in the region of the inlet opening (16) by a guide key (18) which is inserted through a radial assembly gap.

6. The temperature control device according to claim 1, characterized in that: The shaft (32) of the electric motor (3) is mounted in a bearing (31) with a sliding bearing bushing, and the sliding bearing bushing is surrounded by a seal-filled lubricant.

7. The temperature control device according to claim 4, characterized in that: The power electronics (34) are arranged inside the motor housing (13) and are in thermal contact with a housing flange (14) that contacts the spindle housing (10).

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