ELECTRICAL ENERGY STORAGE SYSTEM AND A VEHICLE COMPRISING SUCH AN ELECTRICAL ENERGY STORAGE SYSTEM

Abstract

An electrical energy storage system includes electrochemical energy storage cells for collecting, supplying and storing electrical energy, a contacting device for contacting the energy storage cells, and temperature sensors for monitoring temperature of individual energy storage cells. The electrochemical energy storage cells include a first and second electrical terminal, the contacting device including conductors. A first contacting element connects the first electrical terminal of each cell and a first conductor of the contacting device. A second contacting element connects the second electrical terminal of each cell and a second conductor of the contacting device. The temperature sensors include a thermocouple having a first element from a first metal material and a second element from a second metal material. The first element is connected to one of the terminals or the body of the energy storage cell and the second element is connected to the first element or the body of the energy storage cell.

Claims

1. An electrical energy storage system, comprising: a plurality of electrochemical energy storage cells for collecting, supplying, and storing electrical energy; a contacting device for contacting the energy storage cells; and a plurality of temperature sensors for monitoring a temperature of individual energy storage cells; wherein the electrochemical energy storage cells each comprise a first electrical terminal and a second electrical terminal, wherein the contacting device comprises conductors, wherein a first contacting element connects the first electrical terminal of each cell and a first conductor of the contacting device, and wherein a second contacting element connects the second electrical terminal of each cell and a second conductor of the contacting device, wherein the temperature sensors each comprise a thermocouple having a first element from a first metal material and a second element from a second metal material, and wherein the first element is directly connected to one of the terminals or a body of the energy storage cell and wherein the second element is directly connected to the first element or the body of the energy storage cell.

2. The electrical energy storage system according to claim 1, wherein the contacting device comprises a plurality of openings, wherein head sides of the energy storage cells are disposed in individual openings of the contacting device, and wherein the first contacting element and the second contacting element reach above the openings.

3. The electrical energy storage system according to claim 1, wherein the first element is realized by one of the first contacting element and the second contacting element, and wherein the second element is directly attached to the first element.

4. The electrical energy storage system according to claim 3, wherein the first element is sandwiched between a respective electrical terminal and the second element directly on the respective electrical terminal.

5. The electrical energy storage system according to claim 1, wherein the first element and the second element are attached to the body of the energy storage cell in a distance to each other, and wherein the body of the energy storage cell is electrically conductive and constitutes a third element of the temperature sensor made from a third metal material.

6. The electrical energy storage system according to claim 5, wherein the body comprises the second electrical terminal.

7. The electrical energy storage system according to claim 6, wherein the energy storage cells comprise a plurality of groups, each of the groups having a multitude of energy storage cells, wherein the groups are interconnected in a serial connection, wherein the energy storage cells inside the groups are interconnected in a parallel connection, and wherein one measuring module is provided for each group and is connected to temperature sensors of a respective group.

8. The electrical energy storage system according to claim 7, wherein each measuring module comprises a signal coupler, and wherein the signal couplers of a plurality of measuring modules are connected to an evaluation unit or readout unit.

9. The electrical energy storage system according to claim 2, wherein the contacting device comprises at least one printed circuit board, and wherein the conductors comprise at least one conducting layer on at least one insulation layer.

10. The electrical energy storage system according to claim 7, wherein the contacting device comprises at least one printed circuit board, wherein the conductors comprise at least one conducting layer on at least one insulation layer, wherein the contacting device comprises a printed circuit board for each group, and wherein the measuring module comprises an SMD component attached to or integrated into the respective printed circuit board.

11. The electrical energy storage system according to claim 6, wherein the measuring modules are directly connected to respective second elements of the temperature sensors through individual conductors and to a common electric potential of all first elements.

12. The electrical energy storage system according to claim 1, wherein the second element comprises an electrically insulating substrate having a coating of the second metal material.

13. The electrical energy storage system according to claim 1, wherein the first metal material and the second metal are distinct and selected from a group of materials consisting of copper (Cu), CuNi alloys, iron (Fe), steel, aluminum, cerium (Ce), NiCr alloys, and PtRh alloys.

14. The electrical energy storage system according to claim 1, wherein the electrical energy storage system is configured to conduct a self-test by checking a connecting state between the first elements and respective second elements, or by evaluating a connecting state between the first element and a respective electrical terminal, or by comparing a temporal behavior of measured temperatures of at least a part of all temperature sensors to identify implausible results from a detached temperature sensor.

15. A vehicle comprising an electrical energy storage system according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In the following, the attached drawings are used to illustrate example embodiments in more detail. The illustrations are schematic and not to scale. Identical reference numerals refer to identical or similar elements.

[0045] FIG. 1 shows a part of a contacting device with a temperature sensor in a sectional view;

[0046] FIG. 2 shows the part of the contacting device in another view;

[0047] FIG. 3 shows a part of the contacting device with another temperature sensor;

[0048] FIG. 4 shows an electrical energy storage device in a wiring diagram;

[0049] FIGS. 5-7 show manufacturing of a contacting device;

[0050] FIG. 8 shows an aircraft; and

[0051] FIG. 9 shows a pouch-type storage cell.

DETAILED DESCRIPTION

[0052] FIG. 1 shows a part of an electrical storage system 2 in a sectional view. Here, one of a plurality of interconnected electrochemical storage cells 4 is shown, having a bottom side 6 and a head side 8. On the head site 8, a first electrical terminal 10 is placed. Exemplarily, it protrudes from a substantially cylindrical housing 12. A contacting device 14 is provided, above the head side 8 and comprises a printed circuit board 16 having an opening 18, into which the head side 8 of the storage cell 4 protrudes. A first contacting element in the form of a first tongue 20, which is attached to a conductor track 22 of the printed circuit board 16, is connected to the first electrical terminal 10. A second contacting element in the form of a second tongue is connected to a second electrical terminal, both of which are not shown in FIG. 1.

[0053] A temperature sensor 24 is provided, which comprises a second element 26 that is connected to a through-contact 28, which in turn is coupled with a measuring module 29 explained further below. The second element 26 reaches above the opening 18, overlaps with the first tongue 20 and is attached to an end of the first tongue 20 directly above the first electrical terminal 10. The first tongue 20 is realized from copper, while the second element 26 comprises a CuNi alloy. Consequently, the first tongue 20 and the second element 26 constitute a thermocouple, which generates a thermoelectric voltage directly depending on the temperature of the joint above the first electrical terminal 10. Thus, the first tongue 20 is a first element of the thermocouple. The design of the temperature sensor 24 is thus very simple and only requires the second element 26 and the measuring module 29, which is connected to both the first element, i.e. the first tongue 20, and the second element 26.

[0054] The connection of both the first element 20 and the second element 26 can be done in a single step when connecting the first element, i.e. the first tongue 20, to the first electrical terminal 10 through welding. Thus, the effort for providing a plurality of temperature sensors on the contacting device 14 is clearly reduced.

[0055] FIG. 2 shows the arrangement of the storage cell and the temperature sensor 24 in a different view. The measuring module 29 may comprise an integrated circuit and may be connected to further temperature sensors 24 as shown in FIG. 4.

[0056] FIG. 3 shows a modified system 30, where a first element 32 and a second element 34 are attached to an upper surface 36 of the storage cell 4, wherein free ends of the first element 32 and of the second element 34 are arranged in a distance to each other. The first element 32 may be made from copper, while the second element 34 may comprise CuNi. The housing 12 of the storage cell 4 may in turn be made from aluminum or steel. The housing 12 thus creates a thermocouple pair with each of the first element 32 and the second element 34 and consequently, a kind of three-material thermocouple temperature sensor 38 is created.

[0057] The region, where the ends of the first element 32 and the second element 34 are placed, may comprise the second electrical terminal. Thus, the first element 32 or the second element 34 may also be the first tongue 20 or a second tongue.

[0058] FIG. 4 shows the system 2 in the form of a wiring diagram. Here, three groups 40 of storage cells 4 are connected in a serial connection. Inside each of the groups 40, four storage cells 4 are connected in parallel to each other. Temperature sensors 24 are provided by combining a second element 26 and a first tongue 20, which are attached to a first electrical terminal 10, as shown in FIG. 1. Here, the first electrical terminal 10 is a negative pole of the respective storage cell 4.

[0059] A second electrical terminal 42, which represents a positive pole of the respective cell 4, is connected to a second tongue 44. The second element 24 of each storage cell 4 of each group 40 is connected to a measuring module 29 through one of a plurality of inputs 46. A common potential of the storage cells 4 of each group 40 is connected to a common potential input 48 of the measuring module. Hence, only single inputs are required for measuring each individual temperatures.

[0060] The measuring module 29 is supplied with an operating voltage through a supply unit 50. Each group 40 comprises a single measuring module 29, which is connected to all temperature sensors 24 of the respective storage cells 4. Consequently, three measuring modules 29 are provided for measuring the temperatures of twelve storage cells 4.

[0061] A common signal line 52 is provided for coupling in measurement signals representing the individual temperatures through signal couplers 54. For example, the common signal line 52 delivers a modulated bus or network signal comprising information of all temperature sensors 24.

[0062] FIG. 5 shows an example for manufacturing a part of the contacting device 14 for integrating the temperature sensors 24. Here, the multilayer printed circuit board 16 is provided, into which the first tongue 20 and the second element 26 are integrated through a local metallization, as indicated in partial figure I. In the second partial figure II, the opening 18 is created, e.g. by a laser, to locally remove the material of the printed circuit board 16, which may be a plastic material. Residual glass fibers 56 are then removed afterwards. As a result, the arrangement shown in partial figure III is created. The first tongue 20 and the second element 26 may then be connected to the respective storage cell 4 as shown in FIG. 1.

[0063] FIG. 6 shows an alternative way of manufacturing a part of the contacting device 14. First partial figure I shows a carrier film 58 being locally metallized to form the second element 26. In the partial figure II, through-contacts 28 to the second element 26 are provided. In partial figure III, an opening 18 is provided into the carrier film 58, in analogy to partial figure II of FIG. 5. Still further, the first tongue 20 overlapping the opening 18 is provided in partial figure IV. Afterwards, both sections from partial figures III and IV are laminated onto each other.

[0064] If required, this arrangement may be attached to a mechanical carrier 60 as shown in partial figure I of FIG. 7. As depicted in partial figure II the storage cell 4 will then be assembled as shown in FIG. 1.

[0065] FIG. 8 shows an aircraft 62, into which an electrical energy storage system 2 is integrated.

[0066] FIG. 9 shows an energy storage cell 64 in the form of a pouch. Here, a first contacting element 66 and a second contacting element 68 are connected to a first electrical terminal 70 and a second electrical terminal 72. The electrical terminals 70 and 72 are provided in the form of tabs made from a metal material and are usually thermally well coupled with the interior.

[0067] The first contacting device 66 constitutes the first element of a thermocouple-based temperature sensor 74, while a separate second element 76 is connected to the first contacting device 66 directly on the first electrical terminal 70. A measuring module 78 is connected to the second element 76 and a power source (not shown). It is conceivable that a pack having a plurality of these storage cells 64 is equipped with a plurality of temperature sensors 74. For contacting the cells 64, a contacting device 80 is used, which may simply include a set of conductors in the form of the first and second contacting elements as well as individual second elements 76 branching off a laminated bus bar or similar.

[0068] While at least one example embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the example embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a”, “an” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.

REFERENCE NUMERALS

[0069] 2 electrical storage system [0070] 4 electrochemical storage cell [0071] 6 bottom side [0072] 8 head side [0073] 10 first electrical terminal [0074] 12 housing/body [0075] 14 contacting device [0076] 16 circuit board [0077] 18 opening [0078] 20 first contacting element/first tongue/first element [0079] 22 conductor track [0080] 24 temperature sensor [0081] 26 second element [0082] 28 through-contact [0083] 29 measuring module [0084] 30 electrical storage system [0085] 32 first element [0086] 34 second element [0087] 36 upper surface [0088] 38 temperature sensor [0089] 40 group [0090] 42 second electrical terminal [0091] 44 second contacting element/second tongue [0092] 46 input [0093] 48 common potential input [0094] 50 supply unit [0095] 52 common signal line [0096] 54 signal coupler [0097] 56 residual glass fiber [0098] 58 carrier film [0099] 60 mechanical carrier [0100] 62 aircraft [0101] 64 storage cell [0102] 66 first contacting element/first element [0103] 68 second contacting element [0104] 70 first electrical terminal [0105] 72 second electrical terminal [0106] 74 temperature sensor [0107] 76 second element [0108] 78 measuring module [0109] 80 contacting device