Battery with a housing and a gas channel

Abstract

The present invention relates to a battery (1) with a housing (2), wherein the battery has at least one stack pair (3) inside the housing, wherein a stack pair (3) has at least two stacks (4A, 4B), wherein the stacks each have at least one anode sheet (5), at least one cathode sheet (6) and each have a separator (7) separating the anode sheet and the cathode sheet, wherein the stacks each have a width (B), a length (L) and a height (H), wherein the stacks of a stack pair are arranged in a common plane (E), wherein the common plane is spanned by the width and length of the stacks of the respective stack pair and wherein a gas channel (8) is provided between the stacks of a stack pair.

Description

[0001] The present invention relates to a battery with a housing and a gas channel for discharging gases produced.

[0002] A battery is an electrochemical storage device for electrical energy, in which stored chemical energy is converted into electrical energy through an electrochemical redox reaction during discharge. In the context of the invention, the term "battery" refers to both primary batteries, which are designed for a single discharge and not for recharging, and secondary batteries or accumulators, which are designed and intended for multiple charges. Charging a secondary battery represents the electrolytic reversal of the electrochemical redox reaction that occurs during discharge, achieved by applying an electrical voltage.

[0003] A battery comprises one or more galvanic cells, or battery cells, arranged within an enclosure, usually in the form of a foil pouch or casing. Each battery cell includes two electrodes, a separator positioned between the electrodes for electrical separation, and an electrolyte acting as an ion conductor. The two electrodes of a battery cell differ in terms of their active material, making one electrode anodic and the other cathodic (with respect to each cell discharge). Furthermore, a battery typically includes two terminals integrated into the enclosure, which are electrically connected to the electrodes on the inside of the enclosure via current collectors or electrode tabs.In this configuration, all anodically active electrodes are connected to one of the battery poles and the cathodically active electrodes are connected to the other of the battery poles.

[0004] Prismatic cells have become established for the efficient filling of rectangular housings or pouches. In this design, the electrodes are stacked or folded alternately on top of each other in a rectangular shape, with each electrode separated by a separator. A stack of such rectangular electrodes with a separator is called a stack.

[0005] During electrochemical reactions within the battery, gases can be formed under certain extreme conditions. Particularly in prismatic cells, the dense packing can lead to rapid and uncontrolled gas build-up within the battery. In the worst-case scenario, this can result in a battery explosion.

[0006] To remove the gases produced, battery packs or battery modules are known from the prior art, which have gas channels for this purpose. However, corresponding battery packs or battery modules, such as those known from WO 2023 / 146278 A1, US 2023 / 0291068 A1 and US 11316230 B1, relate to gas handling in battery assemblies, not in individual batteries.

[0007] It is therefore the object of the present invention to provide a battery in which a rapid and uncontrolled increase in gas and, in particular, an explosion is counteracted.

[0008] This problem is solved according to the invention by a battery with a housing, wherein the battery has at least one stack pair inside the housing, wherein a stack pair has at least two stacks, wherein the stacks each have at least one anode sheet, at least one cathode sheet and each have a separator separating the anode sheet and the cathode sheet, wherein the stacks each have a width, a length and a height, wherein the stacks of a stack pair are arranged in a common plane, wherein the common plane is spanned by the width and length of the stacks of the respective stack pair and wherein a gas channel is provided between the stacks of a stack pair.

[0009] In this case, a case can be understood to mean either a foil covering in the form of a "pouch" or a "hard case" in the form of a metal or plastic housing.

[0010] The housing typically has cutouts or contact points for bringing the battery terminals to the outside.

[0011] The arrangement of the stacks of a stack pair in a common plane causes the stacks to face each other at their end faces. A gap exists between the respective end faces of the stacks of a stack pair, thus creating the gas channel.

[0012] A stack pair typically consists of two opposing stacks. However, it is also possible for a stack pair to have more than two stacks, with all stacks of a stack pair arranged in the same plane. In the case of more than two stacks per stack pair, this results in outer and inner stacks. In this case, there are multiple parallel gas channels.

[0013] The individual stacks have at least one cathode sheet and at least one anode sheet, preferably in a rectangular shape, alternately stacked or folded on top of each other.

[0014] It is also possible that the stack pair or pairs are rolled up, resulting in a battery in a jelly-roll construction.

[0015] A cathode sheet is formed by a metal layer, preferably comprising aluminum, and at least one active material located thereon. An anode sheet is formed by a metal layer, preferably comprising copper, and at least one active material located thereon, preferably carbon-based. Preferably, the respective active material is arranged on both sides of the metal layers (double-layer design). Typically, the respective metal layers are coated with the respective active material.

[0016] The individual metal layers serve as current collectors. Preferably, areas of the respective metal layers without active material protrude outwards from the stacks to serve as contact points. These protruding areas are called anode tabs and cathode tabs, respectively.

[0017] The dimensions of the stacks are, for example, in the following ranges: Width: 50 mm - 200 mm Length: 80 mm - 300 mm Height: 5 mm - 50 mm.

[0018] The gas channel(s) between the stacks of a stack pair enable controlled and safe gas venting. This prevents rapid and uncontrolled gas build-ups, for example, due to ongoing electrochemical reactions under certain extreme conditions. This also reduces the risk of explosion and increases battery safety.

[0019] According to a first embodiment of the battery, the anode sheets of the stacks of a stack pair are electrically connected to each other and the cathode sheets of the stacks of a stack pair are electrically connected to each other.

[0020] This eliminates the need to contact each individual stack of a stack pair separately from the outside.

[0021] According to a special embodiment of the previously described embodiment of the battery, the electrically conductive connection is made by connecting, preferably welding, anode tabs or cathode tabs in an anode connection area or cathode connection area between the respective stacks of a stack pair.

[0022] The anode tabs and cathode tabs are formed by areas of the respective metal layers that protrude from the individual stacks without any active material on them.

[0023] A stack typically comprises multiple anode sheets, cathode sheets, and separating dividers. Thus, there are multiple anode tabs and cathode tabs per stack. These multiple anode tabs and cathode tabs of one stack are, for example, bundled together and connected to similarly bundled anode tabs and cathode tabs of the opposite stack of the same stack pair. The connection is preferably made by welding, particularly laser welding. The area where the connection is made is the anode connection area and the cathode connection area, respectively.

[0024] The gas channel is created by the distance between the end faces of the stacks of a stack pair and the bundling of the respective anode tabs or cathode tabs.

[0025] According to a special embodiment of the previously described embodiment of the battery, the anode connection area or cathode connection area each extends only over a partial area, preferably half of the interface between the respective stacks of a stack pair, preferably offset from each other.

[0026] The anode and cathode tabs are preferably stacked alternately in planes along the height of the stacks. To avoid having to connect each anode or cathode tab of a plane within a stack individually to an anode or cathode tab in the corresponding plane of the respective stack of the stack pair, the anode and cathode tabs are connected together in bundles. To enable the connection of both the anode and cathode tabs on opposite sides of the stacks of a stack pair, the connection is made only in a partial area, for example, half of the interface between the respective stacks of a stack pair. A subdivision into several partial areas and the provision of multiple anode and cathode connection areas are also conceivable.

[0027] This makes it easy to electrically connect the anode sheets of the stacks in a stack pair. The same applies to the cathode sheets of the stacks in a stack pair.

[0028] According to another embodiment of the battery, the gas channel runs in the direction of the width of the respective stacks of a stack pair.

[0029] If a stack pair has multiple stacks, several parallel gas channels are formed. The gases produced in the center of the battery can be guided along the path of the gas channel(s) to the edges, specifically to the side walls of the casing that define its width.

[0030] According to another embodiment of the battery, the gas channel runs in the direction of the height of the respective stacks of a stack pair.

[0031] In particular, if the anode connection areas or cathode connection areas only fill a partial area, preferably half of the interface between the respective stacks of a stack pair, a gas channel is formed between the stacks of a stack pair which runs in the direction of the height of the respective stack.

[0032] If a stack pair has multiple stacks, several parallel gas channels are formed. The gases produced in the center of the battery can be guided through the gas channel(s) to the edges, specifically to the side walls of the casing that limit the height.

[0033] According to another embodiment of the battery, the gas channels of the several stack pairs form a channel system.

[0034] The aforementioned embodiments can be explicitly combined with one another, so that a channel system is formed which has gas channels which run in the direction of the height of the stacks, as well as gas channels which run in the direction of the width of the stacks.

[0035] A suitable canal system allows for further improved gas removal.

[0036] According to another embodiment of the battery, the width and length of the respective stacks are greater than their height.

[0037] This allows for a flat design of the battery, which in turn enables good stackability of the individual batteries.

[0038] According to another embodiment of the battery, the housing has a degassing opening and the gas channel and / or channel system is / are connected to the degassing opening in a communicative manner.

[0039] The gases produced are routed from the center of the battery through the gas channel and / or channel system and released from the battery through the degassing opening in the housing. In particular, multiple outlet openings may be provided, which may be located on different and / or identical sides of the housing.

[0040] According to another embodiment of the battery, the stacks of a stack pair are positioned opposite each other with end faces, the end faces being spanned by the height and width of the stacks of the respective stack pair.

[0041] This defines the orientation of the stacks within a stack pair relative to each other. This orientation enables a flat battery design, which facilitates easy stacking.

[0042] If a stack pair has more than two stacks, there are outer stacks and inner stacks. The inner stacks are mutually adjacent with two end faces, while the outer stacks are only adjacent with one end face to an inner stack.

[0043] The invention will be explained in more detail below with reference to the accompanying drawings. These show: Fig. 1. An embodiment of a battery, Fig. 2 a partial view of the Fig. 1, Fig. 3A the partial view from Fig. 2 in a first perspective, Fig. 3B a section of the partial view from Fig. 2 in a second perspective, Fig. 3C a section of the partial view from Fig. 2 in a third perspective, Fig. 4 the channel system of the embodiment Fig. 1, Fig. 5A A schematic view of the arrangement of anode sheets and cathode sheets before connecting the stacks of a stack pair, Fig. 5B a schematic view of the arrangement of anode sheets and cathode sheets after connecting the stacks of a stack pair.

[0044] Fig. Figure 1 shows an embodiment of a battery 1 with a housing 2. The illustrated battery 1 has a prismatic shape with battery terminals 18 and a gassing opening 16. The housing 2 is preferably made of metal and / or plastic.

[0045] Fig. 2 shows the interior of the Fig. The battery 1 shown in Figure 1 has two stack pairs 3A and 3B, each stack pair 3A, 3B comprising two stacks 4A, 4B. It is also possible to provide further stack pairs 3. The stack pairs 3 can also each have more than two stacks.

[0046] Stacks 4A and 4B also have a height H. A stack 4A or 4B typically comprises a multitude of stacked anode sheets 5 and cathode sheets 6, each separated by separators 7 (see figure). Fig. 5A, Fig. 5B). Stacking is preferably carried out in the direction of height H.

[0047] The stacks 4A, 4B of a stack pair 3A and 3B are arranged in a common plane E, wherein the respective common plane E is spanned by the width B and the length L of the stacks 4A, 4B of the respective stack pair 3A and 3B.

[0048] A gas channel 8 forms between the opposing end faces 17A, 17B of stacks 4A, 4B. The gas channel 8 extends in the direction of the width B of the respective stacks 4A, 4B. The common plane E of stacks 4A, 4B of stack pair 3A runs parallel to the common plane E of stacks 4A, 4B of stack pair 3B.

[0049] The gas channel 8 between the respective stacks 4A and 4B of a stack pair 3A and 3B enables controlled and safe gas venting. This prevents rapid and uncontrolled gas increases, for example, due to ongoing electrochemical reactions under certain extreme conditions. This also reduces the risk of explosion and increases the safety of battery 1.

[0050] Fig. 3A shows the interior of the Fig. The battery 1 shown in Figure 1 is depicted in a top view, with identical reference numerals. In particular, the course of the gas channel 8 in the direction of width B (into the plane of the paper) is visible.

[0051] Fig. 3B shows a partial section of the interior of the Fig. The battery 1 shown in Figure 1 is shown from a different perspective. The electrically conductive connections between the anode sheets 5 and the cathode sheets 6 are shown (see Figure 1). Fig. 5A, Fig. 5B). The anode sheets 5 and cathode sheets 6 have anode tabs 9 and cathode tabs 10, respectively, in an anode connection area 11 and cathode connection area 12 between the respective stacks 4A and 4B of a respective stack pair 3A and 3B. The connection is preferably made by welding, in particular laser welding. The gas channel 8 is formed between the end plates 17A and 17B of the stacks 4A and 4B and the anode tabs 10 and cathode tabs 11, respectively.

[0052] In the Fig. The anode tabs 10 and cathode tabs 11 shown in Figure 3B are either anode tabs 10 or cathode tabs 11, and their relative positions are interchangeable. The same applies to the anode connection area 11 and the cathode connection area. The exact positioning of anode tabs 10 and cathode tabs 11 is shown in Figure 3B. Fig. 5A and Fig. 5B described.

[0053] Fig. 3C shows a partial section of the interior of the Fig. The battery 1 shown in Figure 1 is depicted from a different perspective. In particular, the anode connection areas 11 and cathode connection areas 12 of stacks 4A and 4B of the respective stack pairs 3A and 3B are shown. The anode connection areas 11 and cathode connection areas 12 each extend only over a partial area 13, which constitutes less than half of the interface 14 between the respective stacks 4A and 4B of the respective stack pair 3A and 3B.

[0054] Furthermore, it shows Fig. 3C, that on the one hand a gas channel 8 runs in the direction of width B and on the other hand a gas channel 8 runs in the direction of height H. The gas channels 8 of the several stack pairs 3A, 3B form a channel system 15. By forming a channel system 15, additional possibilities for the controlled and safe removal of gases are created, thus further increasing the safety of battery 1.

[0055] Further details of canal system 15 are in Fig. Figure 4 shows the channel system 15. All arrows represent channels through which gases can be extracted. The channel system 15 is connected to the outgassing opening 16, thus enabling controlled and safe extraction of gases from inside the battery 1.

[0056] Fig. 5A and Fig. Figure 5B shows the positioning of the anode sheets 5, cathode sheets 6 and the separating separator 7 in detail. Fig. 5A shows the state before connecting stacks 4A, 4B of a stack pair 3, while Fig. Figure 5B shows the state after connection. Both the anode sheets 5 and the cathode sheets 6 have anode tabs 9 and cathode tabs 10, respectively.

[0057] The anode sheets 5 and cathode sheets 6 are stacked alternately on top of each other in stack 4A and 4B respectively, with a separator 7 arranged between the anode sheets 5 and cathode sheets 6.

[0058] Stack 4A has an anode tab 9 on the left side, which serves for electrical contact with one of the battery terminals. Stack 4A also has an anode tab 9 on the right side, which serves for electrical contact in the anode connection area 11 with the left anode tab 9 of Stack 4B.

[0059] Stack 4A has a cathode tab 10, which serves for electrical contact in the cathode connection area 12 with the left cathode tab 10 of stack 4B. Stack 4B further has a right cathode tab 10, which serves for electrical contact with the other battery terminal.

[0060] The anode connection area 11 and the cathode connection area 12 extend only over a partial area 13 of the interface 14 between the stacks 4A and 4B. In particular, the partial areas 13 comprise less than half of the interface 14. This results in the formation of a gas channel 8 in the direction of the height H of the stacks 4A and 4B (into the plane of the paper), in addition to the gas channel 8 in the direction of the width B of the stacks 4A and 4B, thus forming a channel system 15. Reference symbol (part of the description) 1 battery 2 cases 3, 3A, 3B Stack pair 4A, 4B Stacks 5 anode sheets 6 cathode sheets 7 Separator 8 Gas channel 9 anode tabs 10 cathode tabs 11 Anode connection area 12 Cathode connection area 13 Sub-area 14 Interface between stacks 4A, 4B 15-channel system 16 Degassing opening 17A, 17B End faces of stacks 4A, 4B 18 battery poles B Width, direction of width L Length, direction of length H height, direction of height E plane spanned by B and L QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] WO 2023 / 146278 A1

[0006] US 2023 / 0291068 A1

[0006] US 11316230 B1

[0006]

Claims

[1] Battery (1) with a housing (2), wherein the battery (1) has at least one stack pair (3, 3A, 3B) inside the housing (2), wherein a stack pair (3, 3A, 3B) has at least two stacks (4A, 4B), wherein the stacks (4a, 4B) each have at least one anode sheet (5), at least one cathode sheet (6) and each have a separator (7) separating the anode sheet (5) and the cathode sheet (6), where the stacks (4A, 4B) each have a width (B), a length (L) and a height (H), characterized by , that the stacks (4A, 4B) of a stack pair (3, 3A, 3B) are arranged in a common plane (E), wherein the common plane (E) is spanned by the width (B) and the length (L) of the stacks (4A, 4B) of the respective stack pair (3, 3A, 3B) and that a gas channel (8) exists between the stacks (4A, 4B) of a stack pair (3, 3A, 3B). [2] Battery according to claim 1, characterized by, that the anode sheets (5) of the stacks (4A, 4B) of a stack pair (3) are electrically connected to each other and that the cathode sheets (6) of the stacks (4A, 4B) of a stack pair (3) are electrically connected to each other. [3] Battery according to claim 2, characterized by , that the electrically conductive connection is made by connecting, preferably welding, anode tabs (9) or cathode tabs (10) in an anode connection area (11) or cathode connection area (12) between the respective stacks (4A, 4B) of a stack pair (3). [4] Battery according to claim 3, characterized by , that the anode connection area (11) or cathode connection area (12) each extends only over a partial area (13), preferably half of the interface (14) between the respective stacks (4A, 4B) of a stack pair (3), preferably offset from each other. [5] Battery according to any one of the preceding claims, characterized by, that the gas channel (8) runs in the direction of the width (B) of the respective stacks (4A, 4B) of a stack pair (3). [6] Battery according to any one of the preceding claims, characterized by , that the gas channel (8) runs in the direction of the height (H) of the respective stacks (4A, 4B) of a stack pair (3). [7] Battery according to any one of the preceding claims, characterized by , that the battery has multiple stack pairs (3A, 3B) wherein the common planes (E) of the respective stack pairs (3A, 3B) are parallel to each other. [8] Battery according to claim 7, characterized by , that the gas channels (8) of the several stack pairs (3A, 3B) form a channel system (15). [9] Battery according to any one of the preceding claims, characterized by , that the width (B) and length (L) of the respective stacks (4A, 4B) is greater than their height (H). [10] Battery according to any one of the preceding claims, characterized by, that the housing (2) has a degassing opening (16) and the gas channel (8) and / or the channel system (15) is / are connected to the degassing opening (16) in a communicating manner. [11] Battery according to any one of the preceding claims, characterized by , that the stacks (4A, 4B) of a stack pair (3) are opposite each other with end faces (17A, 17B), wherein the end faces (17A, 17B) are spanned by the height (H) and the width (B) of the stacks (4A, 4B) of the respective stack pair (3).

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