A battery module for an electrical energy storage device for a motor vehicle, an electrical energy storage device, and a method

Abstract

A battery module 10, for an electrical energy storage device 12 of a motor vehicle, comprises several energy storage elements 14, a pressure supply device 28, by which the energy storage elements 14 a

Description

FIELD OF THE INVENTION

[0001] The present invention relates to the field of automobiles. More specifically, the present invention relates to a battery module for an electrical energy storage device of a motor vehicle. Furthermore, the present invention relates to a corresponding energy storage device for a motor vehicle and a method for operating a corresponding battery module. BACKGROUND INFORMATION

[0002] In the state of the art, a battery module, which might be designed as a battery pack, comprises several battery cells. The said battery cells may expand and contract upon charge or discharge and may be integrated in the battery pack using some sort of mechanical mechanism to accommodate the volume change. At the same time, a relatively high stack pressure, for example between 50 kilopascal and 3 megapascal, may be applied as it usually may be beneficial for cell performance. In a thermal event, for example triggered by damage of a cell from the outside, this set-up known from the state of the art may not be beneficial because heat may travel easily from the battery cell with the thermal event to the next battery cell. SUMMARY OF THE INVENTION

[0003] It is an object of the present invention to provide a battery module for an electrical energy storage device of a motor vehicle, a corresponding electrical energy storage device for a motor vehicle, as well as a method for operating a battery module for an electrical energy storage device of a motor vehicle, by which safety of the battery module can be particularly increased.

[0004] This object is solved by a battery module for an electrical energy storage device of a motor vehicle, a corresponding electrical energy storage device for a motor vehicle, as well as a method for operating a battery module for an electrical energy storage device of a motor vehicle according to the independent claims. Advantageous embodiments are presented in the dependent claims.

[0005] One aspect of the present invention relates to a battery module for an electrical energy storage device of a motor vehicle. Preferably, the motor vehicle is designed as a passenger car or a commercial vehicle. Preferably, the motor vehicle is a battery electric vehicle (BEV) or a hybrid vehicle, in particular a plug-in hybrid vehicle (PHEV). The energy storage device may be understood as an accumulator or a battery respectively, which may be referred to as storage battery.

[0006] The battery module comprises several energy storage elements, which are preferably designed as storage cells. The said storage cells may be referred to as battery cells. Therefore, the battery module may be referred to as cell module or cell pack. Preferably, the battery module is designed as a cell array.

[0007] Furthermore, the battery module comprises at least one pressure supply device, by which the energy storage elements are capable of being pressurized or are pressurized. The said pressurization of the energy storage elements may be referred to as stack pressure. This means that the pressure supply device is capable of generating the stack pressure.

[0008] In particular, to increase safety of the battery module, for example safety against the thermal event, the battery module comprises at least one spring element, which is arranged between two adjacent energy storage elements. In other words, a distance is provided between at least two adjacent energy storage elements, wherein the spring element is arranged at the said distance. This means that the intermediate distance between the energy storage elements is at least partially filled by the spring element. The said respective distance may be referred to as spacing, gap or clearance. Moreover, the respective spring element is capable of being displaced from a normal position to a safety position by a reduction of the pressurization of the energy storage elements caused by the pressure supply device. This means that the pressure supply device is capable of reducing the stack pressure, whereby the spring element is moved from the normal position to the safety position. In other words, decreasing the said pressurization by the pressure supply device is accompanied by the movement of the spring element from the normal position to the safety position. In the normal position the spring element is in a compressed state. This means that the movement of the spring element from the normal position to the safety position is accompanied by an expansion of the spring element. When the spring element is displaced from the normal position to the safety position, the adjacent energy storage elements, between which the spring element is arranged, are capable of being impacted by the spring element in order to increase a distance at least between the said adjacent energy storage elements. As a result, the said distance in the safety position is larger than in the normal position. This means that the said distance in a first state of the battery module comprises a first value and in a second state of the battery module comprises a second value that is larger than the first value, wherein a change from the first state to the second state is effected by the displacement from the spring element from the normal position to the safety position. So, the spring is capable of separating the energy storage elements, in particular in the safety position.

[0009] In the present invention, it may be possible to actively create the said spacing, in particular to increase the said spacing, between the energy storage elements due to the expansion of the spring elements, in particular by a method, which depends on moving the spring element from its compressed state to the safety position. This may be triggered by a high temperature condition detected by an electronic computing device or automatically triggered by an independent mechanism. The electronic computing device may be designed as a battery management system. For example, the battery management system may detect a battery condition that may indicate a thermal event such as a thermal runaway event. The battery management system may utilize artificial intelligence and / or other processes to determine a thermal event such as a high temperature after detecting an abnormal pressure or another battery condition. The invention is based in particular on the recognition that the material between cells does not need to be a thermal barrier, which may require more space and may lead to inferior thermal properties during normal operation. Only in the event of a problem, for example, the said thermal event, the battery cells may be put in a thermally much more separated configuration, in particular in the said second state for the safety position. As soon as the stack pressure is removed the energy storage elements may be pushed apart by the spring element. Due to the increase of the distance between the storage elements, heat transfer between the storage elements may be reduced, for example in case of the thermal event. Therefore, an unsafe chain reaction between the storage elements may be avoided securely. In other words, thermal propagation between the storage elements may be avoided securely. Benefits of the present invention may be its simplicity and durability.

[0010] It is therefore clear that with the present invention in case of a safety problem, the energy storage elements may be placed in a beneficial state in terms of thermal propagation. This could apply for any battery assembly even with cylindrical cells, prismatic or pouch cells, and it may not depend on the set up described. Overall, it is recognizable that an on-event battery cell spacing with at least one elastic spring is provided. With the present invention for the on-event battery cell spacing with the spring element, the storage elements may normally be packed denser but moved to a less dense packaging in case of emergency.

[0011] According to an embodiment, the battery module comprises at least one temperature sensor and an electronic computing device by which the pressure supply device is capable of being controlled as a function of a temperature detected by the temperature sensor in order to effect the said displacement of the spring element, in particular from the normal position, to the safety position.

[0012] In another embodiment, the energy storage elements are arranged between two end plates, wherein the energy storage elements are capable of being pressurized or are pressurized by the pressure supply device via at least one of the end plates.

[0013] In another embodiment, the spring element is designed as a mechanical spring.

[0014] In another embodiment, the spring element is made of metal.

[0015] In another embodiment, the pressure supply device comprises a pneumatic system being capable of the said reduction of the pressurization of the energy storage elements in order to move the spring element to the safety position.

[0016] In another embodiment, the pressure supply device comprises a linear motor being capable of the said reduction of the pressurization of the energy storage elements in order to move the spring element to the safety position.

[0017] In another embodiment, the battery module comprises several of the said spring elements.

[0018] Another aspect of the present invention relates to an energy storage device for a motor vehicle, comprising at least the battery module according to the first aspect of the invention. Advantageous embodiments of the electrical energy storage device are to be regarded as advantageous embodiments of the battery module and vice versa.

[0019] Another aspect of the present invention relates to a method for operating a battery module, in particular according to the first aspect of the invention, for an energy storage device, in particular according to the second aspect of the invention, of a motor vehicle. Advantageous embodiments of the method are to be regarded as advantageous embodiments of the battery module and the electrical energy storage device and vice versa.

[0020] The battery module comprises several energy storage elements and at least one pressure supply device, by which the energy storage elements are pressurized. Furthermore, the battery module comprises at least one spring element, which is arranged between two adjacent energy storage elements.

[0021] A still further aspect of the present invention relates to a computer program product comprising program code means for performing a method according to the preceding aspect.

[0022] Furthermore, the present invention relates to a non-transitory computer-readable storage medium comprising at least the computer program product according to the preceding aspect.

[0023] A computing unit / electronic computing device may in particular be understood as a data processing device, which comprises processing circuitry. The computing unit can therefore in particular process data to perform computing operations. This may also include operations to perform indexed accesses to a data structure, for example a look-up table, LUT.

[0024] In particular, the computing unit may include one or more computers, one or more microcontrollers, and / or one or more integrated circuits, for example, one or more application-specific integrated circuits, ASIC, one or more field-programmable gate arrays, FPGA, and / or one or more systems on a chip, SoC. The computing unit may also include one or more processors, for example one or more microprocessors, one or more central processing units, CPU, one or more graphics processing units, GPU, and / or one or more signal processors, in particular one or more digital signal processors, DSP. The computing unit may also include a physical or a virtual cluster of computers or other of said units.

[0025] In various embodiments, the computing unit includes one or more hardware and / or software interfaces and / or one or more memory units.

[0026] A memory unit may be implemented as a volatile data memory, for example a dynamic random access memory, DRAM, or a static random access memory, SRAM, or as a non-volatile data memory, for example a read-only memory, ROM, a programmable read-only memory, PROM, an erasable programmable read-only memory, EPROM, an electrically erasable programmable read-only memory, EEPROM, a flash memory or flash EEPROM, a ferroelectric random access memory, FRAM, a magnetoresistive random access memory, MRAM, or a phase-change random access memory, PCRAM.

[0027] In order to increase safety of the battery module, in particular against the thermal event, the spring element is displaced from a normal position, in which the spring element is in a compressed state, to a safety position by a reduction of the pressurization of the energy storage elements caused by the pressure supply device. As a result, the adjacent energy storage elements, between which the spring element is arranged, are impacted by the spring element in order to increase a distance at least between the said adjacent energy storage elements.

[0028] Further advantages, features, and details of the present invention derive from the following description of preferred embodiments as well as from the drawings. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and / or shown in the figures alone can be employed not only in the respectively indicated combination but also in any other combination or taken alone without leaving the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The novel features and characteristic of the present disclosure are set forth in the appended claims. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and together with the description, serve to explain the disclosed principles. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system and / or methods in accordance with embodiments of the present subject matter are now described below, by way of example only, and with reference to the accompanying figures.

[0030] The drawings show in:

[0031] Fig. 1 a schematic side view of an embodiment of a battery module, wherein a spring element is in a normal position.

[0032] Fig. 2 a schematic side view of an embodiment of a battery module, wherein a spring element is in a safety position.

[0033] Fig. 3 a schematic perspective view of a spring element according to an embodiment of a battery module.

[0034] In the figures the same elements or elements having the same function are indicated by the same reference signs. DETAILED DESCRIPTION

[0035] In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration". Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

[0036] While the present disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawing and will be described in detail below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.

[0037] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion so that a setup, device or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a system or apparatus preceded by “comprises” or “comprise” does not or do not, without more constraints, preclude the existence of other elements or additional elements in the system or method.

[0038] In the following detailed description of the embodiment of the present disclosure, reference is made to the accompanying drawing that forms part hereof, and in which is shown by way of illustration a specific embodiment in which the disclosure may be practiced. This embodiment is described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.

[0039] Fig. 1 shows a schematic side view according to an embodiment of a battery module 10 for an electrical energy storage device 12 of a motor vehicle. The said side view in Fig. 1 may be a sectional view. The motor vehicle is preferably at least in part electrically operated or full electrically operated. Therefore, the motor vehicle may comprise at least one electric motor. Preferably, the electric motor is supplied with energy by the electrical energy storage device 12, in particular by the battery module 10. For example, the electrical energy storage device 12 is designed as a battery, in particular, a low voltage or high voltage battery. A high voltage battery may be 60V to 1500V. battery module 10 comprises several energy storage elements 14. Preferably, the energy storage elements 14 are cells, which may be referred to as battery cells. The battery module 10 is capable of executing a method for operating the battery module 10. For example, the respective battery cell is designed as a cylindrical cell, a prismatic cell, or a pouch cell,

[0040] Furthermore, the battery module 10 comprises a pressure supply device 28 by which the energy storage elements 14, are capable of being pressurized or are pressurized. In other words, the said pressure supply device 28 is capable of applying a force in order to effect the said pressurization of the storage elements 14. The pressure supply device 28 may be referred to as pressure generating device or stack pressure generating device.

[0041] In order to increase safety of the battery module 10, preferably safety against the thermal event, the battery module 10 comprises at least one spring element 16. In the example shown in Fig. 1 the battery module comprises several spring elements 16. The respective spring element 16 may be understood as spring-like device. As shown in Fig. 1, the respective spring element 16 is arranged between two respective adjacent energy storage elements 14. Therefore, the respective spring 16 element may be referred to as intercell spring. The respective energy storage elements 14 are coupled, in particular directly, to each other via the respective spring element 16.

[0042] The respective spring element 16 is capable of being displaced from a normal position 18, in which the spring element 16 is in a compressed state, to a safety position 20 by a reduction of the pressurization of the energy storage elements 14 caused by the pressure supply device 28. Fig. 1 shows the respective spring element 16 in the normal position 18. Fig. 2 shows a schematic side view of the battery module 10 or the storage device 12 respectively, wherein the respective spring element 16 in Fig. 2 is shown in the safety position 20. When the respective spring element 16 is displaced from the normal position 18 to the safety position 20, the adjacent energy storage elements 14, between which the respective spring element 16 is arranged, are capable of being impacted by the respective spring element 16, in particular directly, in order to increase a respective distance between the said respective adjacent energy storage elements 14. This means that the reduction of the pressurization of the energy storage elements 14 is effected by the pressure supply device 28, whereby the respective spring element16 is displaced from the normal position 18 to the safety position 20, in which the respective distance between the respective energy storage elements 14 is increased. Therefore, for example in case of a thermal event, the respective distance between the storage elements 14 may be increased by the respective spring element 16. As a result, heat transfer of the storage elements 14 may be reduced. As shown in Fig. 1, the storage elements 14 and the respective spring elements 16 are formed separately from each other.

[0043] Fig. 1 shows the battery module 10 in a first state, in particular before the said increase of the respective distance between the energy storage elements 14. In the said first state, the respective spring element 16 is in its normal position 18. Fig. 2 shows the battery module 10 in a second state, in which the said increase of the distance between the storage elements 14 has already taken place. This means that the said increase of the distance is illustrated in Fig. 2. In the second state, the respective spring element16 is in its safety position 20. For example, the spring elements 16 do not have to be placed between all energy storage elements 14. It may depend on how many spaces are needed to keep the system in a managed state.

[0044] The pressure supply device 28 may be designed as an activation device which is capable of effecting, in particular initiating, the said displacement of the respective spring element 16 from the normal position 18 to the safety position 20. This means the pressure supply device 28 effects, in particular initiates, the said displacement of the respective spring element 16 to the safety position 20. So, a first step to effect the said displacement may be the reduction of the said pressurization or pressure of the energy storage elements 14, respectively. “Reduction” may be understood as a removal of the pressure 30 at least partially or completely. So, it is possible that the said pressurization of the storage elements 14 by the pressure supply device 28 is omitted during the said displacement of the respective spring element 16 to the safety position 20. Then, the spring elements 16 between the energy storage elements 14 may produce sufficient pressure to separate the cells. In other words, the said pressure 30 is removed while the spring elements 16 are moved to the safety position 20. When the stack pressure 30 generated by the pressure supply device 28 is applied to the spring elements 16, the spring elements 16 are for example compressed to a flat material. This is due to the fact that the stack pressure 30 is a much higher pressure which is capable of deforming the spring elements 16, and in particular keeping the spring elements 16 in the normal position 18. So the pressure supply device 28 is capable of moving the respective spring element 16, in particular from the safety position 20, to the normal position 18 by pressurization of the respective spring element 16.

[0045] In the embodiment shown in Fig. 1 and 2, the energy storage device 12, in particular the battery module 10, comprises at least one temperature sensor 24 and an electronic computing device 26 by which the pressure supply device 28 is capable of being controlled as a function of a temperature detected by the temperature sensor 24 in order to effect the said displacement of the respective spring element 16 to the safety position 20. This means that the temperature sensor 24 may detect the said temperature, and the said electronic computing device 26 may control the pressure supply device 28 as a function of the detected temperature in order to effect the said displacement of the respective spring element 16 to the safety position 20. As a result, it may be possible to move the respective spring element 16 as a function of the detected temperature.

[0046] The electronic computing device 26 may be understood as a data processing device, which comprises processing circuitry. Therefore, the electronic computing device 26 may be referred to as a computing unit. The electronic computing device 26 may, in particular, process data to perform computing operations. This may also include operations to perform indexed accesses to a data structure.

[0047] In particular, the electronic computing device 26 may include one or more computers, one or more microcontrollers, and / or one or more integrated circuits, for example, one or more application-specific integrated circuits, ASIC, one or more field-programmable gate arrays, FPGA, and / or one or more systems-on-a-chip, SoC. The electronic computing device may also include one or more processors, for example one or more microprocessors, one or more central processing units, CPU, one or more graphics processing units, GPU, and / or one or more signal processors, in particular one or more digital signal processors, DSP. The electronic computing device 26 may also include a physical or a virtual cluster of computers or other ones of said units.

[0048] In various embodiments, the electronic computing device 26 includes one or more hardware and / or software interfaces and / or one or more memory units. A memory unit may be implemented as a volatile data memory, for example a dynamic random access memory, DRAM, or a static random access memory, SRAM, or as a non-volatile data memory, for example a read-only memory, ROM, a programmable read-only memory, PROM, an erasable programmable read-only memory, EPROM, an electrically erasable programmable read-only memory, EEPROM, a flash memory or flash EEPROM, a ferroelectric random access memory, FRAM, a magnetoresistive random access memory, MRAM, or a phase-change random access memory, PCRAM.

[0049] In the embodiment shown in Fig. 1 and Fig. 2, the storage elements 14 are arranged between two end plates 32, 34, wherein the storage elements 14 are capable of being pressurized or pressurized by the pressure supply device 28 via at least one of the end plates 32, 34. This means that the storage elements 14, and in particular the spring elements 16, are force loaded, in particular pressure 30 loaded, by the pressure supply device 28 via at least one of the said end plates 32, 34. This is illustrated in Fig. 1 and Fig. 2 by respective pressure 30 arrows. In other words, the said pressure supply device 28 is capable of applying a force to at least one of the end plates 32, 34, in order to generate the said pressure 30. In the example in Fig. 1 and Fig. 2, a first one of the end plates 32 is designed as a mechanical support, and the second one of the end plates 34 is capable of being moved and is force loaded by the pressure supply device 28.

[0050] Fig. 3 shows the spring element 16 in a schematic perspective view according to an embodiment of the battery module 10 of the energy storage device 12, respectively. In the example shown in Fig. 3, the respective spring element 16 is designed as a mechanical spring, which may be referred to as spring. The movement between the normal position and the safety position of the respective spring element 16 is accompanied by an elastic deformation of the respective spring element 16. Preferably, the respective spring element 16 is made of metal. If metal is used, the springs can be designed to last very long without loss of function, even if heated to high temperatures in a thermal event.

[0051] For example, the pressure supply device 28 may include a pneumatic system which is being capable of the said reduction of the pressurization of the energy storage elements 14 in order to move the respective spring element 16 to the safety position. Alternatively, it is possible that the pressure supply device 28 comprises a linear motor being capable of the said reduction of the pressurization of the energy storage elements 14 in order to move the respective spring element 16 to the safety position. In other words, the said pressure removal may be executed by the pneumatic system and / or the linear motor. List of reference signs 10 battery module 12 energy storage device 14 energy storage element 16 spring element 18 normal position 20 safety position 24 temperature sensor 26 electronic computing device 28 pressure supply device 30 pressure 32 first end plate 34 second end plate

Claims

1. A battery module (10) for an electrical energy storage device (12) of a motor vehicle, comprising several energy storage elements (14), a pressure supply device (28), by which the energy storage elements (14) are capable of being pressurized or are pressurized, and at least one spring element (16), which is arranged between two adjacent ones of the energy storage elements (14) and is capable of being displaced from a normal position (18), in which the spring element (16) is in a compressed state, to a safety position (20) by a reduction of the pressurization of the energy storage elements (14) caused by the pressure supply device (28), wherein, when the spring element (16) is displaced from the normal position (18) to the safety position (20), the adjacent energy storage elements (14), between which the spring element (16) is arranged, are capable of being impacted by the spring element (16) in order to increase a distance at least between the said adjacent energy storage elements (14).

2. The battery module (10) according to claim 1, characterized in that the battery module (10) comprises at least one temperature sensor (24) and an electronic computing device (26) by which the pressure supply device (28) is capable of being controlled as a function of a temperature detected by the temperature sensor (24) in order to effect the said displacement of the spring element (16) to the safety position (20).

3. The battery module (10) according to claim 1 or 2, characterized in that the energystorage elements (14) are arranged between two end plates (32, 34), wherein the storage elements (14) are capable of being pressurized by the pressure supply device (28) via at least one of the end plates (32, 34).

4. The battery module (10) according to any one of claims 1 to 3, characterized in that the spring element is designed as a mechanical spring.

5. The battery module (10) according to claim 4, characterized in that the spring element (16) is made of metal.

6. The battery module (10) according to any one of claims 1 to 5, characterized in that the pressure supply device (28) comprises a pneumatic system being capable of the said reduction of the pressurization of the energy storage elements (14) in order to move the spring element (16) to the safety position.

7. The battery module (10) according to any one of claims 1 to 6, characterized in that the pressure supply device (28) comprises a linear motor being capable of the said reduction of the pressurization of the energy storage elements (14) in order to move the spring element (16) to the safety position (20).

8. The battery module (10) according to any one of claims 1 to 7, characterized in that the battery module (10) comprises several of the said spring elements (16).

9. An electrical energy storage device (12) for a motor vehicle, comprising at least the battery module (10) according to any one of claims 1 to 8.

10. A method for operating a battery module (10) for an electrical energy storage device (12) of a motor vehicle, wherein the battery module (10) comprises several storage elements (14), a pressure supply device (28), by which the energy storage elements (14) are pressurized, and at least one spring element (16), which is arranged between two adjacent ones of the energy storage elements (14), wherein the spring element (16) is displaced from a normal position (18), in which the spring element(16) is in a compressed state, to a safety position (20) by a reduction of the pressurization of the energy storage elements (14) caused by the pressure supply device (28), whereby the adjacent energy storage elements (14), between which the spring element (16) is arranged, are impacted by the spring element (16) in order to increase a distance at least between the said adjacent energy storage elements (14).Application No: GB2410948.0Examiner:Dr Steven ChadwellClaims searched: 1-10Date of search: 20 December 2024Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance A - US 2018 / 0301765 Al (KNAPEetal.) A - CN 205609622 U (CONTEMPORARY AMPEREX TECHNOLOGY LTD) also see the English abstracts, including WP1 Abstract Accession No. 2016-643060 A - CN 220753630 U (JIANGSU ZHENGLI XINNENG BATTERY TECHNOLOGY CO LTD) also see the English abstracts, including WPI Abstract Accession No. 2024-389626Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of same category. before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:International Classification:Subclass Subgroup Valid From HO IM 0050 / 289 01 / 01 / 2021 HO IM 0010 / 48 01 / 01 / 2006 HO IM 0050 / 209 01 / 01 / 2021 HO IM 0050 / 211 01 / 01 / 2021 HO IM 0050 / 242 01 / 01 / 2021 HO IM 0050 / 244 01 / 01 / 2021 HO IM 0050 / 249 01 / 01 / 2021 HO IM 0050 / 293 01 / 01 / 2021

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