Device for conditioning a battery pack

Abstract

Device for conditioning a battery pack (2) by cooling and / or heating, - with a plurality of battery modules (3) arranged in at least one conditioning level (4a, 4b), wherein - in each conditioning level (4a, 4b) two or more parallel rows (5a-f) each with two or more battery modules (3) are provided, wherein - each row (5a-f) of battery modules (3) is contacted directly or indirectly via carrier means (10) for the battery modules (3) by at least one separate fluid line (6a-l) through which a liquid or gaseous medium flows, acting as a heat exchanger - the fluid lines (6a-l) are connected in parallel to each other in terms of flow and have a common fluid supply (9a) and a common fluid return (9b), wherein - the fluid lines (6a-l) acting as heat exchangers are themselves geometrically individually designed in such a way that the fluid volume flow penetrating them is adapted to an individual cooling or heating requirement of the respective contacted series (5a-f) battery modules (3), wherein - at least one of the fluid lines (6a-l) in adaptation of the fluid volume flow of the same to an individual cooling or heating requirement of the respective contacted row (5a-f) battery modules (3) has at least one individual partial constriction (11) of a flow cross-section which is constant over its length, and wherein - which has at least one partial constriction (11) in a region of the fluid line (6a-l) between two battery modules (3) contacted by the same.

Description

[0001] The invention relates to a device for conditioning a battery pack by cooling and / or heating according to the combination of features of claim 1 of the invention.

[0002] It is detrimental to a vehicle's energy storage system, such as a high-voltage battery, particularly in electric and hybrid electric vehicles, to be exposed to extreme temperatures for extended periods. Conditioning such a battery, for example by heating it when it is too cold or cooling it when it is too hot, has proven advantageous in ensuring an optimal temperature for the battery's power output and also improving its durability, lifespan, and other aspects. The cooling and / or heating devices are controlled by sensors, specifically based on the current temperature measurement of the battery pack or one or more sections (modules) thereof. The cooling device is, for example, thermally connected to the vehicle's cooling system.The heating device is, for example, thermally connected to a combustion engine of the vehicle and / or electrically operated. The heating and cooling devices can be installed as separate units or combined with each other (see, for example, DE 10 2011 121 245 A1).

[0003] It is known from practical experience that, depending on the geometric arrangement of the battery modules in the battery pack, this arrangement requires either a uniform cooling or heating capacity for the battery modules or individualized cooling or heating capacity to ensure the most identical possible operating temperature of the battery modules and, ideally, of all battery cells arranged within them. For example, DE 10 2010 025 525 A1 discloses a method for cooling battery packs in which at least one battery pack is divided into several battery modules. Each module is assigned a cooling device in the form of a heat exchanger. The coolant connections of the cooling devices are fluidically connected in parallel in a cooling circuit. The coolant flow to each module is regulated by a control valve assigned to that module. Each module has at least one temperature sensor that measures the individual temperature of that module.Depending on the measured temperature, a temperature controller regulates the control valve for the coolant connection of the respective assigned module.

[0004] From DE 10 2010 032 899 A1, a vehicle battery assembly with battery cell groups (battery modules) is further disclosed, wherein each battery cell group is assigned exactly one separate cooling device. The cooling devices are connected to a cooling circuit. The cooling device comprises a cooling base with a flat contact surface for planar contact with the battery cell group. The cooling base has, for example, two U-shaped flat lines with a coolant inlet and a coolant outlet. The flat lines are, for example, formed as extruded aluminum profiles. The flat line has several coolant channels distributed across its width. A restrictor is provided between the coolant inlet connection and each of the two coolant inlets. The restrictors are intended to ensure a desired, and in particular uniform, distribution of the coolant to the two coolant inlets of the U-shaped flat lines.The coolant inlets are designed as distributors to ensure an even distribution of the coolant to the individual coolant channels.

[0005] From DE 10 2009 013 651 A1, a device for conditioning a battery pack by cooling is known, with fluid lines connected in parallel to each other in terms of flow technology and having a common fluid supply and a common fluid return, wherein the fluid lines themselves functioning as heat exchangers are geometrically individually designed, for example having different pipe cross-sections or different throttles with differently constricted cross-sections.

[0006] Further measures for conditioning or cooling a battery pack are known from DE 10 2013 200 362 A1, WO 2009 / 121 613 A1, JP S63- 16 562 A, KR 10 2005 0 007 648 A and WO 2013 / 178 577 A1.

[0007] The object of the invention is to create a device for conditioning a battery pack by cooling and / or heating, which, in the simplest design of the device, nevertheless enables individualization of the cooling and / or heating performance of the cooling and / or heating devices assigned to the battery modules and designed in the manner of a heat exchanger, in order to ensure an optimal, ideally identical temperature of all battery modules of the battery pack.

[0008] The invention is based on the understanding that the cooling and / or heating capacity of a fluid-operated heat exchanger can be adjusted depending on the fluid's volume flow rate. Volume flow rate, as understood in the field, is the volume of a medium that moves through a flow cross-section, in this case the flow cross-section of the fluid line, within a unit of time.

[0009] The problem is therefore solved by a device for conditioning a battery pack by cooling and / or heating, - with a plurality of battery modules arranged in at least one conditioning level, wherein - in each conditioning level, two or more parallel rows, each containing two or more battery modules, are provided, wherein - each row of battery modules is directly or indirectly contacted by at least one separate fluid line through which a liquid or gaseous medium flows, acting as a heat exchanger, via a carrier means for the battery modules, wherein - the fluid lines are connected in parallel to each other in terms of flow technology and have a common fluid supply and a common fluid return, wherein - the fluid lines acting as heat exchangers are themselves geometrically individually designed in such a way that the fluid volume flow penetrating them is adapted to an individual cooling or heating requirement of the respective contacted series of battery modules, wherein - at least one of the fluid lines, in adapting the fluid volume flow rate to an individual cooling or heating requirement of the respective contacted row of battery modules, has at least an individual partial narrowing of a flow cross-section that is otherwise constant over its length, and wherein - which includes at least a partial constriction in an area of ​​the fluid line between two battery modules contacted by the same line.

[0010] A conditioning level is understood to be a level in which multiple battery modules are arranged side by side. Several conditioning levels, each with multiple battery modules, can be arranged one above the other.

[0011] This creates a structurally simple and cost-effective device for conditioning the battery pack through cooling and / or heating. Simply by adjusting the geometry and design, the fluid lines, which function as heat exchangers, can accommodate any varying cooling or heating requirements of the connected row of battery modules, since the flow rate, and thus the cooling or heating capacity, of these fluid lines can be preset through geometric adjustment. Technically complex sensors and control technologies for adjusting the flow rate of the heat exchanger fluid, as favored by current state-of-the-art technology, are advantageously avoided.

[0012] The dependent claims describe preferred further developments or embodiments of the invention.

[0013] It is then provided that the required cooling or heating demand of the connected series of battery modules, and thus the geometric adaptation of the associated fluid line to it, is determined empirically or computationally. This is done in particular depending on certain boundary conditions, which may include, for example, the length of the supply lines to the fluid lines, the length of the fluid lines themselves, their cross-section, their material selection, the choice of heat exchanger fluid used, the preferred operating area of ​​the vehicle (warm climate, such as subtropical or tropical countries, or cold climate, such as Nordic countries), etc. A structurally simple measure for partially narrowing the flow cross-section of the fluid line is achieved by embossing the fluid line, which is preferably made of a highly thermally conductive metal, especially a light metal, such as aluminum.It is further advantageous that the battery modules of each conditioning level are contacted at least on their bottom side by the respective associated fluid line to ensure effective conditioning of the resulting battery pack. To further optimize this conditioning, when the battery modules are arranged in two or more conditioning levels, the battery modules of the lower conditioning level are additionally contacted by the bottom-side fluid line of the battery modules of the conditioning level immediately above, either directly or indirectly via one or more carrier means for the battery modules of the conditioning level immediately above.In a further development of the invention, the support means are / are formed by a thermally conductive surface element, preferably made of metal, in particular a light metal such as aluminum or an aluminum alloy. The support means can have multiple openings to further adapt the heat transfer to the individual cooling or heating requirements of the lower battery modules. As for the fluid lines, these are preferably formed by a flat line, thereby creating a sufficiently large contact area with the battery module. The flat line can be formed, for example, by an elongated hollow profile, such as a continuously cast profile, with one or more flow channels, or by a conventional tube with one or more attached cooling fins that contact the battery modules.

[0014] The invention is explained in more detail below with reference to the exemplary embodiments schematically depicted in the drawings. However, it is not limited to these, but encompasses all embodiments defined by the claims. The drawings show: Fig. 1 a perspective view of a battery pack arranged in a battery tray of a vehicle with several battery modules arranged in two planes and with a device for conditioning the battery pack by cooling and / or heating, which has a plurality of fluid lines connected in parallel in terms of flow, as heat exchangers, which are contacted with the battery modules, Fig. 2 the battery pack including the device without illustration of the battery tray, Fig. 3 a diagram which, with regard to a conventional device for conditioning the battery pack by cooling and / or heating, shows the flow rate of a heat exchanger fluid per unit of time (volume flow) and fluid line, Fig. 4 the device for conditioning the battery pack by cooling and / or heating in a perspective single view with fluid lines according to a first embodiment according to the invention, Fig. 5 the detail “Z” after Fig. 4, Fig. 6 the cut “II” after Fig. 5, Fig. 7. The representation of a device for producing a fluid line of the apparatus, Fig. 8 further development of the device according to Fig. 4, Fig. 9 a diagram which, with regard to the device according to the invention for conditioning the battery pack by cooling and / or heating, shows the flow rate of the heat exchanger fluid per unit of time (volume flow) and fluid line, and Fig. 10 a sectional view of the fluid lines of a device for conditioning the battery pack according to a second embodiment not covered by the invention.

[0015] Fig. Figure 1 shows a battery tray 1, which is used in a vehicle not shown in the drawing, in particular an electric vehicle and hybrid electric vehicle, and which accommodates a battery pack 2, such as a high-voltage battery. Fig. For clarity, Figure 2 shows the aforementioned battery pack 2 without the battery tray 1. The battery pack 2 consists of two or more battery modules 3. A conditioning device is associated with the battery pack 2. Conditioning refers to a measure that ensures that all battery modules 3 of the battery pack 2, and ideally all battery cells arranged within them (not shown in the drawing), have as identical an operating temperature as possible.

[0016] According to this embodiment, a battery pack 2 is provided with twenty-four (24) battery modules 3, which are arranged in two superimposed conditioning levels 4a, 4b, namely a first lower and a second upper conditioning level, each containing twelve (12) battery modules 3. Furthermore, the battery modules 3 in each conditioning level 4a, 4b are arranged in six (6) parallel rows 5a to 5f, each row containing two (2) battery modules 3.

[0017] The device for conditioning the battery pack 2 has fluid lines 6a-l, which are preferably designed as so-called flat lines and function as heat exchangers by contacting the battery modules 3. According to Fig. 5 and Fig. 6. Preferably elongated hollow profiles of the type of a flat box profile. Uses that include or according to Fig. 10 also have several flow channels 7. The flat pipes are, for example, designed as extruded profiles and preferably consist of metal, in particular light metal, such as aluminum or an aluminum alloy, which has high thermal conductivity. However, the invention is not limited to such flat pipes, but also covers flat pipes that are formed, for example, by a conventional pipe with one or more coupled cooling fins that contact the battery modules (not shown in the drawing). The heat exchanger fluid can be liquid or gaseous. For cooling, for example, a mixture of water and glycol can be used.

[0018] Each row 5a-f of battery modules 3 in each conditioning level 4a, 4b is assigned a separate fluid line 6a-f, 6g-I as a heat exchanger with a fluid inlet 8a and a fluid outlet 8b. The fluid lines 6a-l are connected in parallel with each other and have a common fluid supply 9a and a common fluid return 9b. The fluid supply 9a is directly connected to a fluid inlet 8a, designed as a distribution pipe, of the fluid line 6g of the second upper conditioning level 4b. The fluid return 9b is directly connected to a fluid outlet 8b, designed as a distribution pipe, of the fluid line 6l of the second upper conditioning level 4b.

[0019] The remaining fluid lines 6a-f, 6h-k are also fluidically integrated into the common cooling and / or heating circuit in accordance with the parallel connection already mentioned, by the distribution pipes of the fluid inlets 8a and the distribution pipes of the fluid outlets 8b of the battery modules 3 of the second upper conditioning level 4b being arranged axially one behind the other and connected to each other, and the distribution pipes of the fluid inlets 8a and the distribution pipes of the fluid outlets 8b of the battery modules 3 of the first lower conditioning level 4a being fluidically connected to the distribution pipe of the fluid inlet 8a or fluid outlet 8b of the second upper conditioning level 4b directly above them.

[0020] According to a practical embodiment of the invention, the battery modules 3 of the first lower conditioning level 4a are placed directly on their respective associated fluid lines 6a-f (flat lines), the fluid lines 6a-f being supported on the base of the battery trough 1 (not shown in the drawing). Similarly, according to a practical embodiment of the invention, the battery modules 3 of the second upper conditioning level 4b are placed directly on their respective associated fluid lines 6g-I (flat lines), these fluid lines 6g-I being each supported on a support element 10, which in this case acts as an intermediate floor and is in turn supported either directly or indirectly on the battery trough 1 (see in particular the following). Fig. 8) The support means 10 is in this case formed by a surface element (sheet) made preferably of thermally conductive metal, in particular light metal, such as aluminium or an aluminium alloy, or of steel.

[0021] Assuming that it takes place starting from Fig. Four identically designed fluid lines 6a-l functioning as heat exchangers were used, and tests showed that, according to the diagram... Fig. 3. Each fluid line 6a-l has a volume flow rate (fluid throughput per unit of time) such that a high volume flow rate is observed in fluid lines 6a, 6g and 6f, 6l, whereas, moving away from these towards fluid lines 6d, 6j, the volume flow rate of the remaining fluid lines decreases successively with increasing distance. This leads to differential cooling or heating of the series 5a-f fluid lines 6a-l, which must be avoided in order to ensure an optimal, ideally identical, temperature for all battery modules 3 of the battery pack 2.

[0022] In order to counteract this disadvantageous circumstance and, for example, to establish a largely identical volume flow rate in all fluid lines 6a-f, 6g-I, at least in the respective conditioning level 4a, 4b, according to the state of the art (DE 10 2010 025 525 A1), it is possible to achieve an optimal adjustment of the volume flow rate for each fluid line 6a-l by means of costly sensors and control and regulation technologies for associated control valves.

[0023] Exemplary embodiment of the invention ( Fig. 4-9): The applicant, however, takes a different approach. It is intended that the fluid lines 6a-f, 6g-I, which function as heat exchangers, are themselves geometrically individually designed in such a way that the fluid volume flow penetrating them is adapted to the individual cooling or heating requirements of the respective contacted series 5a-f fluid lines 6a-l. Specifically, this means that first, the required cooling or heating requirements of the contacted series 5a-f fluid lines 6a-I, and thus the geometric adaptation of the respective assigned fluid line 6a-I to this requirement, are determined empirically or computationally, and subsequently, the fluid lines 6a-I are designed accordingly or appropriately prepared fluid lines 6a-l are provided.

[0024] With the Fig. Figures 4 to 6 show a first measure for adapting the fluid volume flow of each fluid line 6a-I to the individual cooling or heating requirements of the respective connected series 5a-f battery modules 3. This measure is characterized by the fact that each fluid line 6a-I has, or can have, an individual partial constriction 11 of the otherwise constant flow cross-section along its length. "Individual" in this context means that the constriction 11 is designed specifically for the respective fluid line 6a-I. Of course, a configuration is also possible in which two or more fluid lines 6a-I have an identically designed constriction 11. By means of such a constriction, the respective volume flow can be influenced or adjusted very conveniently.Extensive tests on the subject matter of the application have shown it to be particularly advantageous that at least one constriction 11 is arranged in a region of the fluid line 6a-l between two battery modules 3 contacted by the same (see in particular . Fig. 4).

[0025] Such a narrowing 11 can be represented, for example, by embossing the fluid lines 6a-l which are designed as flat lines in this case. Fig. Figure 7 shows a suitable device 12 for embossing, which by way of example has two embossing rollers 13, by means of which a constriction 11 directed transversely to the flow direction 14 of the volume flow of the cross-section of the fluid line 6a-I which is otherwise constant over the length of the respective fluid line 6a-I can be effected by arranging the fluid line 6a-I in question between said embossing rollers 13 and applying pressure to at least one of the embossing rollers 13.

[0026] Again Fig. As can be seen further in Figure 8, as already explained above, the battery modules 3 of each conditioning level 4a, 4b are contacted at their base by the respective associated fluid line 6a-f, 6g-I. To further optimize said conditioning, in an arrangement of the battery modules 3 in two or more conditioning levels 4a, 4b one above the other, as provided for in this embodiment, the battery modules 3 of the lower conditioning level 4a are additionally contacted by the base-side fluid line 6g-I of the battery modules 3 of the conditioning level 4b directly above, either directly or indirectly via the support means 10 for said battery modules 3 of the conditioning level 4b directly above. The support means 10 have a plurality of openings 15 for this purpose, which allows the heat transfer to be further adapted to the individual cooling or heating requirements of the lower battery modules 3.

[0027] According to the diagram Fig. Figure 9, which shows the flow rate of the heat exchanger fluid per unit of time (volume flow) and per fluid line 6a-l with regard to the device according to the invention for conditioning the battery pack 2 by cooling and / or heating, shows the volume flows of the fluid lines 6a-f of the first lower conditioning level 4a and the volume flows of the fluid lines 6g-I of the second upper conditioning level 4b by geometrically individual adjustment of the fluid lines 6a-f, 6g-I of each conditioning level 4a, 4b to each other as far as possible.Notwithstanding this, the flow rates of the fluid lines 6g-I of the second upper conditioning level 4b are set higher than the flow rates of the fluid lines 6a-f of the first lower conditioning level 4a, since the fluid lines 6g-I of the second upper conditioning level 4b simultaneously serve to condition (cool or heat) the battery modules 3 of the first lower conditioning level 4a. For example, the isolation of the battery modules 3 of the first lower conditioning level 4a from above results in a heat build-up, which is countered by additional cooling via the fluid lines 6g-I of the second upper conditioning level 4b.

[0028] The advantageous measure described above for adapting the fluid volume flow of each fluid line 6a-I to the individual cooling or heating requirements of the respective contacted series 5a-f battery modules 3 is therefore based on at least one individual partial narrowing 11 of the flow cross-section of the respective fluid line 6a-l, which is constant over its length.

[0029] Exemplary embodiment which is not covered by the subject matter of the invention ( Fig. 10);

[0030] In contrast, a second measure for adapting the fluid volume flow of each fluid line 6a-I to the individual cooling or heating requirements of the respective contacted series 5a-f battery modules 3 provides that the fluid lines 6a-l each have an individual flow cross-section in themselves, i.e., a flow cross-section that is constant over the length but individual. Fig.Figure 10 shows, as examples, three different flow cross-sections of fluid lines 6a-l with regard to the respective desired volume flow, from which a choice can be made as required. Reference symbol list 1 battery tray 2 battery packs 3 battery modules 4a first conditioning level 4b second conditioning level 5a-f series (3 battery modules) 6a-l Fluid line 7 Flow channel 8a Fluid inlet (fluid line 6a-l) 8b Fluid outlet (fluid line 6a-l) 9a Fluid supply 9b Fluid return 10 carrier media 11 Narrowing 12. Embossing device 13 embossing rollers 14 Flow direction 15 breaches

Claims

[1] Device for conditioning a battery pack (2) by cooling and / or heating, - with a plurality of battery modules (3) arranged in at least one conditioning level (4a, 4b), wherein - in each conditioning level (4a, 4b) two or more parallel rows (5a-f) each with two or more battery modules (3) are provided, wherein - each row (5a-f) of battery modules (3) is contacted directly or indirectly via carrier means (10) for the battery modules (3) by at least one separate fluid line (6a-l) through which a liquid or gaseous medium flows, acting as a heat exchanger - the fluid lines (6a-l) are connected in parallel to each other in terms of flow and have a common fluid supply (9a) and a common fluid return (9b), wherein - the fluid lines (6a-l) acting as heat exchangers are themselves geometrically individually designed in such a way that the fluid volume flow penetrating them is adapted to an individual cooling or heating requirement of the respective contacted series (5a-f) battery modules (3), wherein - at least one of the fluid lines (6a-l) in adaptation of the fluid volume flow of the same to an individual cooling or heating requirement of the respective contacted row (5a-f) battery modules (3) has at least one individual partial constriction (11) of a flow cross-section which is constant over its length, and wherein - which has at least one partial constriction (11) in a region of the fluid line (6a-l) between two battery modules (3) contacted by the same. [2] Device according to claim 1, characterized by, that the required cooling or heating requirement of the respective contacted series (5a-f) battery modules (3) and thus the geometric adaptation of the respective associated fluid line (6a-l) to the same is determined empirically or computationally or can be determined. [3] Device according to claim 2, characterized by , that at least one partial constriction (11) is formed by deformation of the fluid conduit (6a-l). [4] Device according to any one of claims 1 to 3, characterized by , that the battery modules (3) of each conditioning level (4a, 4b) are contacted at least on the bottom side by the respective associated fluid line (6a-l). [5] Device according to any one of claims 1 to 4, characterized by, that in an arrangement of the battery modules (3) in two or more conditioning levels (4a, 4b) one above the other, the battery modules (3) of the respective lower conditioning level (4a) are additionally contacted by the bottom-side fluid line (6g-I) of the battery modules (3) of the conditioning level (4b) arranged directly or indirectly via one or more carrier means (10) for the said battery modules (3) of the conditioning level (4b) arranged directly above. [6] Device according to claim 5, characterized by , that the carrier means (10) is / are formed by a thermally conductive surface element. [7] Device according to claim 6, characterized by , that the carrier(s) (10) has / have a plurality of perforations (15). [8] Device according to any one of claims 1 to 7, characterized by that the fluid lines (6a-l) are each formed by a flat line.

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