Arrester element of an electrode arrangement of a plurality of electrochemical cells

Abstract

A protector element for an electrode configuration of a plurality of electrochemical cell units includes a first conductive region and a second conductive region, wherein each of the second conductive regions includes at least two conductive finger elements, wherein in each case, one electrode of the electrochemical cell unit of the electrode configuration, particularly an anode or cathode, is electrically connected to at least two of the finger elements of one of the second conductive regions, wherein the first conductive region is electrically connected to the second conductive region, and the conductive connection between the first conductive region and the second conductive region is at least partially interrupted in a non-conductive manner, wherein the protector element is formed of nickel-plated steel.

Description

Technical Field

[0001] The present invention, as described in the preamble of the independent claims, relates to a protector element based on an electrode configuration of a plurality of electrochemical cell units, a method for manufacturing a battery system having the protector element, and the use of the protector element in an energy storage device. Prior Technology

[0002] The starting point of this invention is document EP 3631882, which was filed by the applicant and published on November 29, 2018, which discloses a protector element for the electrode configuration of a plurality of electrochemical cell units. Summary of the Invention

[0003] [Advantages of this invention] []

[0004] The process according to the invention includes: a protector element comprising a first conductive region and a second conductive region, wherein each of the second conductive regions comprises at least two conductive finger elements, wherein in each case, one electrode of the electrochemical cell unit of the electrode configuration, particularly the anode or cathode, is electrically connected to at least two of the finger elements of one of the second conductive regions, wherein the first conductive region is electrically connected to the second conductive region, and the conductive connection between the first conductive region and the second conductive region is at least partially interrupted in a non-conductive manner. Furthermore, according to the invention, the protector element is formed of nickel-plated steel.

[0005] Thus, the electrochemical cell units can be electrically connected to each other, and the current, especially the rated current, can flow between the first and second regions without any substantial voltage loss.

[0006] Here, it will be noted that nickel-plated steel, especially high-purity nickel-plated steel, is also known by the name "Hilumin".

[0007] This nickel-plated steel has relatively high corrosion resistance and relatively good electrical conductivity. Furthermore, this significantly improves the tripping speed of the fuse; for example, the tripping time is reduced by approximately 40% compared to pure nickel.

[0008] This accelerated breakout significantly reduces the risk of heat propagation, thereby improving overall safety. Furthermore, the accelerated breakout also allows for an increase in the material thickness of the protector element. Compared to pure nickel, the material thickness can be increased, for example, from 0.2 mm to 0.3 mm. Protector elements with greater material thickness are generally more robust in terms of vibration and shock resistance. In addition, protector elements with greater material thickness have relatively better solderability and allow for the formation of stronger and more reliable connections in the process.

[0009] In addition, nickel-plated steel is relatively inexpensive, for example, compared to nickel.

[0010] Further advantageous embodiments are described in the appendices of the claims in this application.

[0011] The fusible region is formed by a non-conductive interruption, thereby reducing the current-carrying capacity of the conductive connection between the first conductive region and the second conductive region.

[0012] Advantageously, the fusible region can be manufactured in a process-safe manner using conventional stamping and bending methods, and has sufficiently high mechanical load tolerance, such as vibration and temperature changes.

[0013] When the critical current flowing between the first and second regions is exceeded, the electrical connection between one of the second regions and the first region is interrupted. Due to the fusible region, the current-carrying capacity of the electrical connection between the first and second regions is reduced, resulting in a fuse forming a web-like connection. For example, the interruption of the electrical connection can occur independently by fusing the fusible region of the electrical connection between the first and second regions in the event of a fault.

[0014] As a result, for example during abnormal operating conditions, at least one short-circuited electrochemical cell can be disconnected from the circuit, thereby reliably preventing further heating. Consequently, cascading reactions are substantially prevented with high reliability compared to prior art.

[0015] By appropriately selecting the geometry of the fusible region, the current-carrying capacity can be matched to individual applications; that is, a critical value for the maximum permissible current flowing between the first and second regions can be defined.

[0016] The finger-like element has at least a third conductive region that is electrically connected to the second conductive region.

[0017] Advantageously, the second conductive region allows for safe process contact between the electrochemical cell unit, particularly the electrodes, and the third conductive region. The third conductive region is also advantageously suited for resistance welding methods.

[0018] Advantageously, the width of the fusible region is between 0.3 mm and 2 mm, particularly 0.5 mm, and / or the length is between 1 mm and 5 mm, particularly 1 mm.

[0019] Advantageously, the width of the fusible region is between 0.3 mm and 2 mm, particularly 0.75 mm, and / or the length is between 0.5 mm and 5 mm, particularly 1 mm.

[0020] Advantageously, the protector element has a material thickness between 0.1 mm and 5 mm, particularly between 0.2 mm and 0.5 mm.

[0021] Advantageously, the third conductive region has a convex or concave shape. As a result, a sufficiently small contact area is achieved for the welding current during the resistance welding method. In one embodiment, the third region includes a protrusion that substantially recovers its shape during resistance welding.

[0022] A method for manufacturing a battery system having a plurality of electrochemical battery cells and a protection element according to the present invention includes the following steps: Protector components are manufactured using the following methods: A conductive blank is rolled from nickel-plated steel, thereby forming the first region of the protector element; The first region, which has been stamped and rolled, is thereby forming a second region that specifically includes two conductive finger-like elements, and / or a plurality of non-conductive interruptions; A plurality of battery cells are inserted into a battery cell holder, particularly in an alternating configuration of the electrodes of the plurality of battery cells; A plurality of protective elements are inserted to make mechanical contact with the electrodes; By resistance welding at least two conductive finger elements in each of the second regions to make contact between the finger elements and the electrodes of the battery cell, a series circuit and / or parallel circuit of the plurality of battery cells is formed; An electrical contact is established between the protector element and the terminal rod of the battery system.

[0023] In an alternative embodiment, the stamped second region is bent to form a third region electrically connected to the second region, and contact is established between each region of the second region of the finger element and at least two third regions of the conductive finger element and the electrodes of the battery cell by resistance welding to form a series circuit and / or parallel circuit of the plurality of battery cells.

[0024] Advantageously, the battery system according to the invention, having a plurality of electrochemical cell units and protection elements, can be manufactured using conventional manufacturing methods. Furthermore, a highly automated production process is feasible.

[0025] The adjustment of the series and / or parallel circuits of the plurality of battery cells can be achieved by simple geometric changes to the protector elements.

[0026] Advantageously, the protective element according to the invention is used in the energy storage of electric vehicles, hybrid vehicles, plug-in hybrid vehicles, electric-assisted bicycles or electric bicycles, portable devices for telecommunications or data processing, handheld power tools or food processors, and stationary storage for storing, in particular, renewable energy. Simple Explanation of the Diagram

[0027] Exemplary embodiments of the present invention are illustrated in the drawings and will be explained in more detail in the following description.

[0028] In the diagram: [Figure 1] shows a battery system with a protector element according to a first embodiment of the present invention; and [Figure 2] shows a schematic detailed view of a first embodiment of the protector element; and [Figure 3] shows a second embodiment of the protector element according to the present invention; and [Figure 4] shows a schematic diagram of the fuse-breaking behavior of a first embodiment of the protector element according to the present invention. Implementation

[0029] In all the diagrams, the same element symbols refer to the same device elements.

[0030] Figure 1 shows a battery system with a protector element according to a first embodiment of the present invention. The battery system 100 includes a plurality of electrochemical battery cells 109, 110, 111, 112, 113 inserted into a battery cell holder 106, and a protector element 101 having a first conductive region 101(1), a second conductive region 101(2), and a third conductive region 101(3). In the illustrated embodiment, the second region 101(2) includes a first conductive finger 101(2a) and a second conductive finger 101(2b). The first third region 101(3a) is present on the first finger 101(2a), and the second third region 101(3b) is present on the second finger 101(2b). Furthermore, the second region 101(2) includes an extended region 105, which, for example, can compensate for movement of the electrochemical battery cells in the battery cell holder 106, and / or can ensure physical spacing between the protector element 101 and the housings of the battery cell holder 106 and / or the electrochemical battery cells 109, 110, 111, 112, 113.

[0031] The first region 101(1) and the second region 101(2) are electrically connected, wherein a non-conductive interruption is provided, for example, in the form of a notch 132, which reduces the current-carrying capacity of the conductive connection. In the illustrated embodiment, the notch 132 is stamped out, i.e., non-conductive. The first, second, and third fusible regions 130(1), 130(2), 130(3) and the further fusible regions 131(1), 131(2) are formed by the notch 132.

[0032] In the illustrated embodiment, the first battery cell 109, the third battery cell 111, and the fifth battery cell 113 have been inserted into the battery cell holder 106 with their cathodes oriented toward the battery cell holder 106. The second battery cell 110 and the fourth battery cell 112 have been inserted into the battery cell holder 106 with their anodes oriented toward the battery cell holder 106.

[0033] The first and second finger portions 101(2a) and 101(2b) are electrically connected to the electrodes of the electrochemical cell units 109, 110, 111, 112, and 113, preferably through a connection produced by a resistance welding method.

[0034] In the illustrated embodiment, the second and fourth battery cells 110, 112 are connected in parallel, or the first, third, and fifth battery cells 109, 111, 113 are connected in parallel. The second and fourth battery cells 110, 112 are electrically connected in series with the first, third, and fifth battery cells 109, 111, 113 via a protector element 101.

[0035] Typical rated current flows through the fusible regions 130(1), 130(2), 130(3) or 131(1), 131(2) without any substantial voltage drop. If a short circuit occurs in any of the battery cells 109, 110, 111, 112, 113, the first, second, and third fusible regions 130(1), 130(2), 130(3) or the first and second fusible regions 131(1), 131(2) will be heated to the point of melting within a short time, and each battery cell 109, 110, 111, 112, 113 will be electrically disconnected from the first region 101(1) of the protector element 101.

[0036] This isolation occurs in the series direction. Electrical monitoring of the voltage level on each individual protector element 101 is performed by the battery management system on connected measuring lines, which are soldered to a lateral end of each protector element. Isolation in the series direction has a substantial advantage over disconnection in the parallel direction according to the prior art because it results in all battery cells “downstream” of the disconnection area being similarly disconnected relative to the measuring lines, and as a result, the battery management system is no longer able to monitor the state of those battery cells.

[0037] Figure 2 shows a first schematic detail of a first embodiment of the protector element. The electrochemical cell 410 is electrically contacted with the protector element 401 via a second region 401(2). The protector element 401 is electromechanically connected to the electrodes of the cell 410 via third regions 401(3a) and 401(3b), for example, by a connection created by resistance welding.

[0038] During resistance welding, a considerable portion of the current may flow from the electrode of cell 410 through the protector element 401 through the second finger of the second region 401(2) and back to the electrode from there through the first finger of the second region 401(2). This undesirable current is indicated by element symbol 441 in FIG. 2. This unavoidable boundary condition needs to be considered in the geometry of the finger of the second region 401(2) of the protector element 401 so that adjacent fusible areas are not damaged by heating or by heat input that reduces current carrying capacity.

[0039] In the illustrated embodiment, the length 442 of the finger portion of the second region 401(2), for example between 3 mm and 10 mm, is selected in such a way that the resistance is adjusted such that during resistance welding, the current 440 flows substantially entirely from the third region 401(3b) of the second finger portion of the second region 401(2) through the electrode of the battery cell 410 to the third region 401(3a) of the first finger portion of the second region 401(2) of the protector element 401.

[0040] The resistance of the first and second fingers of the second region 401(2) of the protector element 401 can be further increased by selecting the geometry 443 and 445, resulting in a further reduction of the undesirable current 441 and substantially eliminating damage caused by resistance welding during the production process.

[0041] Figure 3 shows a second embodiment of the protector element according to the invention in the form of a battery cell connector 501 for an electrochemical battery cell. Fifteen battery cells can be electrically connected in parallel to form a so-called column via the battery cell connector 501, and two of these columns can be connected in series.

[0042] The battery cell connector 501 includes a first region 501(1) and a second region 501(2), wherein the second region 501(2) includes a first finger portion 501(2a) and a second finger portion 501(2b). Furthermore, the first finger portion 501(2a) includes a first third region 501(3a), and the second finger portion 501(2b) includes a second third region 501(3b).

[0043] The conductive connection between the first region 501(1) and the second region 501(2) includes a plurality of non-conductive interruptions, for example having cutouts 532a, 532b, thereby advantageously forming fusible regions 530a, 530b, 530c or 530d, 530e according to the invention.

[0044] In the illustrated embodiment, the three fusible regions 530a, 530b, 530c or the two fusible regions 530d, 530e are advantageously 0.5 mm and 0.75 mm wide, respectively. The battery cell connector 501 has a material thickness of substantially 0.3 mm. As a result, a total cross-sectional area of ​​0.45 mm² is generated for both the three fusible regions 530a, 530b, 530c and the two fusible regions 530d, 530e.

[0045] The battery cell connector 501 shown in Figure 3 is manufactured by, for example, rolling a conductive blank, stamping the rolled blank, and then bending it.

[0046] If the battery cell connector 501 is used in an energy storage system, a short circuit event in the electrochemical battery cell causes the fusible regions 530a, 530b, and 530c of the corresponding battery cell connector 501 to be rapidly heated to temperatures above the melting point of the material. The fusible regions 530a, 530b, and 530c actually have currents of different magnitudes flowing through them, which advantageously leads to a cascading effect.

[0047] In the case of three fusible regions 530a, 530b, and 530c, this means that the first fusible region among the three fusible regions 530a, 530b, and 530c will melt, resulting in current distribution among the remaining fusible regions. In fact, the current flowing through one of the fusible regions in the two mesh connections is greater than the current flowing through the other fusible region, resulting in the first of the two fusible regions melting again. Therefore, after a certain time span, all the current now flows through only one of the three fusible regions 530a, 530b, and 530c, resulting in this region also melting. As a result, the electrical connection between the first region 501(1) and the second region 501(2) is electrically isolated. Due to the fusible regions, a faster tripping time than in the prior art can be achieved, especially a tripping time of less than 5 seconds.

[0048] Figure 4 shows a schematic diagram of the fusing behavior of a first embodiment of a protector element according to the present invention. The protector element 601 includes a first region 601(1) electrically connected to a second region 601(2), wherein the conductive connection is at least partially interrupted in a non-conductive manner, for example by cuts 632a, 632b. Due to the fusible regions 630a, 630b, 630c, the current-carrying capacity of the electrical connection between the first region 601(1) and the second region 601(2) is reduced, resulting in the formation of a fuse by means of an electrical connection having a mesh-like structure. When a critical current flowing between the first region 601(1) and the second region 601(2) is exceeded, the electrical connection between one of the second regions 601(2) and the first region 601(1) is interrupted. By fusing the fusible regions 630a, 630b, and 630c of the electrical connection between the first region 601(1) and the second region 601(2), the electrical connection can be independently interrupted in the event of a fault.

[0049] Before time t0, the protector element 601 is in normal operating mode, where the typical rated current can flow through all fuseable regions 603a, 630b, and 630c.

[0050] At time t0, due to a battery cell malfunction, such as a short circuit in the battery cell, the second region 601(2) of the battery cell and the protector element 601 is rapidly heated in a short time, and the first fusible region 630c melts at time t1 due to an abnormal current flowing through it exceeding the rated current.

[0051] Therefore, after time t1, the abnormal current now flows only through the fusing regions 630a and 630b. Since the cross-section of the fusing region 630b is smaller than that of the fusing region 630a, the fusing region 630b melts at time t2, where, in particular, it can be expected that the difference between the time spans t2 and t1 will be smaller than the difference between the time spans t1 and t0.

[0052] After time t2, all abnormal currents now flow through the fusible region 630a, which fuses at time t3, where it is particularly expected that the difference between the time spans t3 and t2 will be smaller than the difference between the time spans t2 and t1.

[0053] After time t3, the battery cell is irreversibly isolated from the protector element 601, thus achieving a safe state and reliably preventing the heating caused by the discharge current from spreading to other battery cells.

[0054] 100: Battery System 101: Protector Components 101(1): First conductive region / First region 101(2): Second conductive region / Second region 101(2a): Conductive finger portion / finger portion 101(2b): Conductive finger portion / finger portion 101(3): Third conductive region 101(3a): First and Third Regions 101(3b): Second and Third Regions 105: Extended Area 106: Battery cell retainer 109: Electrochemical cell unit / First cell unit 110: Electrochemical cell unit / second cell unit 111: Electrochemical cell unit / Third cell unit 112: Electrochemical cell unit / Fourth cell unit 113: Electrochemical cell unit / Fifth cell unit 130(1): Fuseable area / First fuseable area 130(2): Fuseable area / Second fuseable area 130(3): Fuseable area / Third fuseable area 131(1): Fuseable area / First fuseable area 131(2): Fuseable area / Second fuseable area 132: Incision 401: Protector Components 401(2): Second Region 401(3a): Third Region 401(3b): Third Region 410: Electrochemical cell unit / cell 440: Current 441: Undesirable Current 442: Length 443: Geometric Shapes 445: Geometric Shapes 501: Battery cell connector 501(1): First area 501(2): Second Region 501(2a): First finger-like part 501(2b): Second finger-like part 501(3a): First and Third Regions 501(3b): Second and Third Regions 530a: Fuseable area 530b: Fuseable area 530c: Fusible area 530d: Fuseable area 530e: Fuseable area 532a: Incision 532b: Incision 601: Protector Components 601(1): First conductive region / First region 601(2): Second conductive region / Second region 630a: Fuseable area 630b: Fuseable area 630c: Fusible area 632a: Incision 632b: Incision t0: Time t1: Time t2: Time t3: Time t4: Time

Claims

1. A protector element (101, 401, 501, 601) for an electrode configuration of a plurality of electrochemical cell units (109, 110, 111, 112, 113, 410), comprising a first conductive region (101(1), 501(1), 601(1)) and a second conductive region (101(2), 401(2), 501(2), 601(2)), wherein each of the second conductive regions (101(2), 401(2), 501(2), 601(2)) comprises at least two conductive finger elements (101(2a), 101(2b), 501(2a), 501(2b), 601(2a), 601(2b)), wherein in each case, the electrode configuration of the plurality of electrochemical cell units (109, 110, 111, 112, 113, 410) The finger elements (101(2a), 101(2b), 501(2a), 501(2b), 601(2a), 601(2b)) of one of the second conductive regions (101(2), 401(2), 501(2), 601(2)) are electrically connected to at least two of the first conductive regions (101(1), 601(1)) and the second conductive regions (101(2), 401(2), 501(2), 601(2)), and the conductive connection between the first conductive region (101(1), 501(1), 601(1)) and the second conductive region (101(2), 401(2), 501(2), 601(2)) is at least partially interrupted in a non-conductive manner, characterized in that the protector element is made of nickel-plated steel.

2. The protector element (101, 401, 501, 601) as described in claim 1, wherein, The fusible regions (130(1), 130(2), 130(3)) are formed by non-conductive interruptions (132, 532a, 532b, 632a, 632b), wherein the fusible regions reduce the current-carrying capacity of the conductive connection between the first conductive region (101(1), 501(1), 601(1)) and the second conductive region (101(2), 401(2), 501(2), 601(2)).

3. The protector element (101, 401, 501, 601) as described in claim 1 or 2, wherein, When the critical value of the current flowing between the first conductive region (101(1), 501(1), 601(1)) and the second conductive region (101(2), 401(2), 501(2), 601(2)) is exceeded, the conductive connection between one of the second conductive regions (101(2), 401(2), 501(2), 601(2)) and the first conductive region (101(1), 501(1), 601(1)) is interrupted.

4. The protector element (101, 401, 501, 601) as described in claim 1 or 2, wherein, The finger elements (101(2a), 101(2b), 501(2a), 501(2b), 601(2a), 601(2b)) have a third conductive region (101(3)) that is electrically connected to the second conductive region (101(2), 401(2), 501(2), 601(2)).

5. The protector element (101, 401, 501, 601) as described in claim 2, wherein, The width of the fusing region (130(1), 130(2), 130(3), 131(1), 131(2)) is between 0.3 mm and 2 mm and / or the length is between 1 mm and 5 mm.

6. The protector element (101, 401, 501, 601) as described in claim 1 or 2, wherein, The protector elements (101, 401, 501, 601) have a material thickness between 0.1 mm and 5 mm.

7. The protector element (101, 401, 501, 601) as described in claim 4, wherein, The third conductive region (101(3)) has a convex or concave shape.

8. A method for manufacturing a battery system having a plurality of electrochemical battery cells (109, 110, 111, 112, 113, 410) and protector elements (101, 401, 501, 601), comprising the following steps: The protector elements (101, 401, 501, 601) are manufactured by rolling a conductive blank from nickel-plated steel, thereby forming a first region (101(1), 601(1)) of the protector elements (101, 401, 501, 601), such that the protector elements are composed of the nickel-plated steel; and stamping the rolled first region (101(1), 501(1), 601(1)) to form a second region (101(2), 401(2), 501(2), 601(2)) including two conductive finger elements (101(2a), 101(2b), 501(2a), 501(2b), 601(2a), 601(2b)), and / or a plurality of non-conductive interruptions (132, 532a, 532b, 632a, 632b). The plurality of battery cells (109, 110, 111, 112, 113, 410) are inserted into a battery cell holder in an alternating arrangement of their electrodes; a plurality of protector elements (101, 401, 501, 601) are inserted and make mechanical contact with the electrodes; By resistance welding at least two conductive finger elements (101(2a), 101(2b), 501(2a), 501(2b), 601(2b)) in each of at least two third regions (101(3), 101(3a), 101(3b)) electrically connected to the second region (101(2), 401(2), 501(2), 601(2b)) to provide the finger elements with the second region (101(2), 401(2), 501(2b), 601(2a), 601(2b)) for resistance welding. Contact is made between the electrodes of the components (101(2a), 101(2b), 501(2a), 501(2b), 601(2a), 601(2b)) and the battery cells (109, 110, 111, 112, 113, 410) to form a series and / or parallel circuit of the plurality of battery cells (109, 110, 111, 112, 113, 410); and an electrical contact is established between the protector elements (101, 401, 501, 601) and the terminal rods of the battery system (100).

9. Use of a protector element (101, 401, 501, 601) as claimed in any one of claims 1 to 7 for use in an energy storage device, the energy storage device being used in an electric vehicle, a hybrid vehicle, an electric-assisted bicycle or electric bicycle, a portable device for telecommunications or data processing, a handheld power tool or a food processor, or a stationary storage device for storing renewable electrical energy.

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