Method for producing an electrochemical storage cell, and an electrochemical storage cell

Abstract

A method for producing an electrochemical storage cell is presented. The method comprises the steps of: providing a flat, substantially circular contact disc (200) having at least two contact segments (201, 202), which each form a circular cutout in the contact disc (200) and are arranged symmetrically around the centre point (204) of the contact disc (200), and wherein between the contact segments (201, 202) circular cutouts (205, 206) are removed from the contact disc (200) and are arranged symmetrically around the centre point (204) of the contact disc (204); arranging an electrode coil (190) in a cylindrical cell housing (110), wherein the electrode coil (190) comprises a series of electrode layers (1); contacting the electrode coil (190) by bringing a peripheral region of the series of electrode layers into contact with a first face of the contact segments (201, 202) of the contact disc (200); and welding the electrode coil (190) to the contact disc by applying welding arcs (209) to a second face (208) of the contact segments (201, 202) that is facing away from the first face of the contact disc (200), wherein the welding arcs (209) are arranged at least partially concentrically around the centre point (204).

Description

[0001] METHOD FOR PRODUCING AN ELECTROCHEMICAL STORAGE CELL

[0002] AND ELECTROCHEMICAL STORAGE CELL

[0003] The following description relates to a method for producing an electrochemical storage cell and an electrochemical storage cell.

[0004] State of the art

[0005] Modern electrochemical storage cells, battery cells, or cells for short, are subject to increasingly stringent requirements regarding their space-to-performance ratio. This presents numerous technical challenges. One of these concerns the efficient contacting of the electrodes. Cylindrical battery cells, also called round cells, are a possible design for electrochemical storage cells used in a wide variety of applications such as electric vehicles, electronic devices, energy storage systems, and emergency power supplies. These cells have the advantage of a high energy density ratio compared to flat battery cells, as they offer better heat dissipation and greater mechanical stability. They also have low resistance and are therefore often used for applications requiring a high discharge rate.

[0006] Round cells comprise an electrolyte, a cathode, an anode, and a separator, which are rolled together to form an electrode coil, also known as a jelly roll structure. The electrodes are designed, for example, as metal foils. The electrode coil is then placed in a cylindrical housing made of metal or plastic, which serves as a current collector. One technical challenge lies in establishing contact between the electrodes of the electrode coil and the cell housing. In the prior art, the electrodes are provided, for example, with electrically conductive tabs, which are welded to a contact disk after the electrode coil has been assembled into the housing. The contact disk thus creates an electrically conductive connection between the electrodes or metal foils and the poles or cell housing.

[0007] To date, a variety of electrode coils with different tab designs have been proposed, such as the so-called "variant-distance tab" and "kneading tab" designs for cylindrical cells. However, the conventional design with a flat, disc-shaped contact disc is still used as the current collector for cylindrical cells. This does not sufficiently utilize the advantages of the various tab designs. Therefore, it is necessary to identify the weaknesses of the current design and make appropriate improvements. This also requires the development of optimized welding patterns that correspond to the disc design of current cylindrical battery cells.

[0008] The design of contact discs for cylindrical cells is usually divided into six to eight parts, of which three to four are evenly distributed as current paths. The others serve as reinforcement parts. The shape of the divided contact discs can block the fluid flow due to a boundary layer effect. Since the vent in a cylindrical cell is usually located in the winding core, the structure of the contact discs should account for gas exhaust during thermal events and maintain the current path during regular cell operation. However, state-of-the-art solutions exhibit gas exhaust disturbances, which can often block the exhaust flow, making it difficult to meet safety requirements.

[0009] Typical welding patterns play an important role in sealing the cell. Along with a favorable design for contact discs, appropriate welding patterns should also be developed according to the disc design. The welding patterns in cylindrical electrochemical storage cells depend on the design and size of the cell. Some commonly used welding patterns for cylindrical electrochemical cells are simple butt welding, in which the two ends of the cylinder are welded together to form a complete cell. Double seam welding creates a double seam where the two ends of the cylinder are folded over each other and then welded. Tubular welding uses a tubular electrode to weld the two ends of the cylinder together.Resistance welding is a form of welding in which an electric current is used to heat and then weld the two ends of the cylinder. Laser welding uses laser technology to melt the two ends of the cylinder and then join them together to form the cell. Other welding patterns can also be used depending on the specific requirements of the electrochemical cell. It is an object to propose a method for manufacturing an electrochemical storage cell and an electrochemical storage cell that at least partially overcome the limitations of the prior art discussed above.

[0010] These objects are achieved by a method for producing an electrochemical storage cell and by an electrochemical storage cell having the features of the independent and subordinate patent claims. Advantageous embodiments and further developments of the invention are set forth in the dependent claims.

[0011] Summary

[0012] It is understood below that each feature described with respect to any embodiment may be used alone or in combination with other features described herein, and may be used in combination with one or more features of any other embodiment, or in any combination of any other embodiment, unless explicitly described as an alternative. Furthermore, equivalents and modifications not described below may be used without departing from the scope of the claimed subject matter.

[0013] The following presents a method for producing an electrochemical storage cell. According to one embodiment, a flat, substantially circular contact disk with at least two contact segments is first provided. The contact segments each form a circular section of the contact disk and are arranged symmetrically around the center of the contact disk. Circular sections are cut out of the contact disk between the contact segments and are arranged symmetrically around the center of the contact disk.

[0014] In a further step, an electrode coil is arranged in a cylindrical cell housing, the electrode coil comprising a sequence of electrode layers. The electrode coil is electrically connected to the contact segments by bringing an edge region of the sequence of electrode layers into contact with a first surface of the contact segments of the contact disk. Finally, the electrode coil is welded to the contact disk by applying welding arcs to a second surface of the contact segments facing away from the first surface of the contact disk. The welding arcs are arranged at least partially concentrically around the center point.

[0015] For example, the weld arcs follow the geometric shape of the contact disk. The number of contact segments is not subject to any restrictions here or in the following. The two segments presented here are intended as examples. The number of contact segments can be determined based on considerations of the desired cell design.

[0016] The proposed method allows the production of an electrochemical storage cell with a design that is largely independent of the arrangement and shape of the conductive tabs of the electrode coil. For example, no tabs or different tabs can be used, shaped, and arranged. Examples include, but are not limited to, a relief cut, a variant distance relief cut, and kneading. However, more advantages can be achieved with a relief cut than with kneading. The relief cut and kneading shapes can also be used in combination for combined tab shapes.

[0017] The performance of an electrochemical storage cell depends on effective functional distribution. The tabs on the edge of the contact disc, which serve as a current path, play a key role in this. The shortened current path generates less heat, improving cell performance and enabling greater rapid charging capability. The even current distribution also increases service life, improves FC performance, and reduces fluid resistance. The symmetrical spacing of recessed circular cutouts between the contact segments optimizes the electrolyte and gas paths, leading to reduced disruption when the vents open. This increases safety by reducing short circuits between the positive contact disc and the negatively polarized cell casing in the event of nail pin penetration. The contact discs can also be welded using arc welding in a faster process.

[0018] The improved concept presented here is based in particular on the considerations outlined below. The contact disk for the electrochemical storage cell can be divided into uniform contact segments, for example, two, three, or four contact segments. In this way, a uniform current path can be achieved and limiting effects minimized. The contact segments are arranged symmetrically and designed to be contacted together to ensure sufficient gas outlet path in the event of thermal triggering and, at the same time, to have a uniform current path in the core and outer region of the electrode coil. An advantageous welding path according to this disk design is an arc that can connect all terminals in the welding area and acts as a current path.A larger welding area can ensure that the current path remains uniform regardless of the C-rate, which is associated with rapid charging and vibration and plastic deformation in the vehicle area.

[0019] Further considerations include a contact disk with a current collector design structure featuring a symmetrical current path and a connecting path that can prevent clogging of the vent in the event of thermal tripping. A connecting path can be welded to the terminal, providing a sufficient current path while ensuring uniform current distribution in the electrode coil. An arc welding pattern can connect the terminals (tabs) in the electrode coil and current collector regardless of the tab shape, such as variable spacing, normal relief cut, or "kneading," and can contribute to performance enhancements such as fast charging.

[0020] An energy storage cell here refers to an electrochemical energy storage device, in particular a rechargeable energy storage device, which is suitable for storing electrical energy and delivering it to a consumer, for example, a consumer in a vehicle. The electrochemical energy storage cell is in particular a lithium-ion battery or a sodium-ion battery, so the following description relates in particular to a lithium-ion battery or a sodium-ion battery.

[0021] In the following, the term "lithium-ion battery" is used synonymously for all designations commonly used in the prior art for lithium-containing galvanic elements and cells, such as lithium battery, lithium cell, lithium-ion cell, lithium-polymer cell, lithium-ion battery cell, and lithium-ion accumulator. Furthermore, the term "sodium-ion battery" is used synonymously for all designations commonly used in the prior art for sodium-containing galvanic elements and cells, such as sodium battery, sodium cell, sodium-ion cell, sodium-polymer cell, sodium-ion battery cell, and sodium-ion accumulator. The aspects presented in this description are not limited to specific types of galvanic elements and cells, but can be used for lithium, magnesium, and sodium-ion batteries, among others.For example, types that use SO2 as an electrolyte can be used. This includes, in particular, rechargeable batteries, so-called secondary batteries. The terms "battery" and "electrochemical cell" are also used synonymously with the terms "lithium-ion battery" and "lithium-ion cell," or "sodium-ion battery" and "sodium-ion cell."

[0022] The contact disc is a flat, circular disc with a center point. It consists of at least two interconnected or separate contact segments, each forming a circular section of the disc and arranged symmetrically around the center of the disc. There can also be more than two contact segments, which are also arranged symmetrically around the center of the disc. If the contact segments are interconnected, this means that the contact disc is made from one piece and the contact segments represent parts of the disc. Alternatively, the contact segments can also be separate or consist of several parts. Between the contact segments there are openings or recesses that are arranged symmetrically and form another circular section of the disc.A circular sector (also called a circular segment) is the area of ​​a circle that is at least partially bounded by a circular arc and two circular radii (as opposed to a "circular segment / section" bounded by a circular arc and a chord). A circular sector looks like a slice of a pie viewed from above.

[0023] According to one embodiment, the contact segments of the circular contact disc can be connected to one another or can be separate from one another.

[0024] According to one embodiment, the electrode coil is formed by winding the electrode layer sequence into a cylinder. The electrode layer sequence is brought into contact with a first surface of the contact disk oriented at right angles to the electrode layer sequence. The electrode sequence comprises a contacting region or edge region which is bent (in particular bent by 180°) (for example before winding) such that the contacting region thus bent contacts the first surface and is welded to the contact disk. According to one embodiment, the contact disk is welded to a first end of the electrode coil. Furthermore, a further contact disk is welded to a second end of the electrode coil opposite the first end. The contact disk has an opening in the region of the center point.The further contact disc has a continuous connection area between the contact segments of the contact disc in the area of ​​the center point.

[0025] According to one embodiment, the contacting region comprises electrically conductive tabs, each of which is bent (for example, before winding and in particular bent by 180°) such that the conductive tabs contact the first surface of the contact disk. The thus bent tabs are welded to the contact disk.

[0026] According to one embodiment, the conductive tabs are arranged in the contacting area such that the bent tabs contact the contact disk only in the area of ​​the contact segments.

[0027] Furthermore, an electrochemical storage cell is proposed. According to one embodiment, the storage cell comprises a cylindrical cell housing and an electrode coil arranged in the cylindrical cell housing. The electrode coil comprises an electrode layer sequence.

[0028] The electrochemical storage cell further comprises a flat, substantially circular contact disk with at least two interconnected or separate contact segments. The contact segments each form a circular section of the contact disk and are arranged symmetrically around the center of the contact disk. Between the contact segments, circular sections are cut out of the contact disk and are also arranged symmetrically around the center of the contact disk.

[0029] The electrode coil is in electrically conductive contact with a first surface of the contact segments of the contact disk via an edge region of the electrode layer sequence. Furthermore, the electrode coil with the contact disk is subjected to welding arcs with a second surface of the contact segments facing away from the first surface of the contact disk. The welding arcs are arranged at least partially concentrically around the center point. According to one embodiment, the electrode layer sequence is wound into a cylinder, thus forming a cylindrical electrode coil. The electrode layer sequence is in electrically conductive contact with the first surface of the contact disk, which is oriented at right angles to the electrode layer sequence, and is welded to it.

[0030] According to one embodiment, the contacting area comprises conductive tabs that are bent over. The bent tabs are welded to the contact disk.

[0031] According to one embodiment, the conductive tabs are arranged in the contacting area such that the bent tabs contact the contact disk only in the area of ​​the contact segments.

[0032] According to one embodiment, the contact disc has an opening in the center region. Alternatively, the contact disc has a continuous connecting area between the contact segments of the contact disc in the center region.

[0033] Further aspects of the electrochemical storage cell arise from the process for producing an electrochemical storage cell discussed here, and vice versa.

[0034] Various exemplary embodiments are illustrated and described in the following drawings. Further details, embodiments, and optimizations emerge. To facilitate recognition, identical or similar components are provided with the same reference numerals throughout the drawings. The proportions of the illustrated components are not to scale. If components or parts perform a similar function in different drawings, the description is not necessarily repeated in each drawing.

[0035] In detail:

[0036] Figure 1 shows a section through a cylindrical electrochemical storage cell, Figures 2A to 2D show embodiments of a contact disc for an electrochemical storage cell,

[0037] Figures 3A to 3D show further embodiments of a contact disk for an electrochemical storage cell, and

[0038] Figure 4 shows an embodiment of a cylindrical electrochemical storage cell.

[0039] Detailed description

[0040] Figure 1 shows a cylindrical electrochemical storage cell 100 (hereinafter referred to as a battery cell or round cell) in a schematic sectional view. It can be, for example, a lithium-ion cell or a sodium-ion cell. The round cell 100 shown is suitable, for example, for electric vehicles. Typically, several battery cells 100 are combined to form a battery pack (not shown), forming a battery for an electric vehicle (not shown), in particular a drive battery for an electric motor of the electric vehicle. The battery cell 100 can, for example, have a diameter of 46 mm and a length of 95 mm.

[0041] The battery cell 100 has a housing 110 in the form of a hollow cylinder made of an electrically conductive material. An electrode winding 120 is arranged in the housing 110, which can be formed by winding a sequence of electrode layers around a winding core 190. The sequence of electrode layers typically comprises several electrode layers, for example, an anode and a cathode. An anode of the electrode winding 120 is contacted with a first contact disk 200 (for example, an anode contact disk) by means of current collectors 150, which are designed, for example, as tabs of the anode. The first contact disk 200 is connected to a base plate 130 of the housing 110 via corresponding electrical connections 140. The base plate 130, like the first contact disk 200, can comprise copper or another metal, wherein the battery cell 100 can be electrically connected from outside the battery cell 100 through the base plate 130.

[0042] Similarly, on a side of the hollow cylinder 110 opposite the base plate 130, a contact plate 170 is arranged. The contact plate comprises an electrically conductive material and is electrically connected to a second contact disk 200 (referred to as the cathode contact disk) via electrical connections 180 and further to the cathode via corresponding current collectors 160 (e.g., tabs), so that the battery cell 100 can be electrically connected from outside the battery cell 100 via the second contact disk 200. The contact plate 170 and the electrical connections 180 comprise, for example, aluminum or another metal. The current collectors 160, as well as the previously mentioned current collector 150, are produced, for example, by compression or folding and can thus make electrically conductive contact with the respective contact disks 200. The reverse polarity and arrangement of the battery cell 100 shown is exemplary.Alternatively, the cell can also be reversed so that the anode and cathode are swapped.

[0043] Figures 2A to 2D show exemplary embodiments of a contact disk for an electrochemical storage cell. They each show flat, essentially circular contact disks 200, which can be used to contact the electrode coil 120, for example, a cylindrical round cell 100. The electrode coil 120 typically comprises the electrode layer sequence with one or more anode layers and one or more cathode layers. The contact disks 200 serve to electrically contact the anode or the cathode and thus each provide a current path for the electrodes. In this way, the electrodes can be contacted via the poles of the round cell 100. The contact disks 200 comprise an electrically conductive material, for example, metal.

[0044] The contact disk 200 in Figure 2A is an exemplary embodiment of an anode contact disk. The disk is shown in plan view and comprises two interconnected contact segments 201, 202, each forming a circular section of the contact disk 200 and connected to one another via an arc 203. The contact segments 201, 202 are arranged symmetrically around the center point 204 of the contact disk 200. Between the contact segments 201, 202, regions 205, 206 are cut out of the contact disk 200, which also form circular sections. These regions 205, 206 are also arranged symmetrically around the center point 204 of the contact disk 200. In the embodiment as an anode contact disc, the disc 200 has a central opening 207 around the center point 204, which is partially bordered by the arc 203 and opens towards one of the recessed areas 205.This central opening 207 is preferably larger than the winding core 190 of the electrode winding 120 in order to prevent material from blocking the opening 207 in the event of a thermal safety event and thus to be able to be more easily removed from the central opening 207. The contact disk 200 is configured to contact the electrode winding 120. For this purpose, an edge region of the electrode layer sequence can be brought into contact with a first surface of the contact segments 201, 202 (below the disk in the drawing) of the contact disk 200. The edge region comprises the current collectors 150, 160 and can, for example, have conductive tabs that can be bent over such that the contact disk 200 can be placed on the edge region with the current collectors 150, 160 (for example, the bent over tabs), and the tabs then touch or make electrically conductive contact with the first surface of the contact segments 201, 202.

[0045] Figure 2B shows the anode contact disk from Figure 2A with multiple welding arcs 209. The electrode coil 120 is welded to the contact disk 200 by applying the welding arcs 209 to a second surface 208 of the contact segments 201, 202 facing away from the first surface 208 of the contact disk 200. Due to the partially circular contact segments 201, 202 (circular sections), the welding arcs 209 form partial arcs of a circle and are arranged at least partially concentrically around the center point 204.

[0046] The contact disk 200 in Figure 2C is an exemplary embodiment of a cathode contact disk. The disk 200 is shown in plan view and comprises two interconnected contact segments 201, 202, each forming a circular section of the contact disk 200 and connected to one another via a connected, here circular, connecting region 210. The contact segments 201, 202 are arranged symmetrically around the center point 204 of the contact disk 200. Between the contact segments 201, 202, regions 205, 206 are removed from the contact disk 200, which also form circular sections. These regions 205, 206 are also arranged symmetrically around the center point 204 of the contact disk 200. In the embodiment as a cathode contact disk, the disk 200 does not have a central opening 207 around the center point 204, but rather the connecting region 210.

[0047] The contact disk 200 is configured to contact the electrode coil 120. For this purpose, similar to the anode contact disk, an edge region of the electrode layer sequence 1 can be brought into contact with a first surface of the contact segments 201, 202 of the contact disk 200. The edge region can, for example, have conductive tabs that can be bent over such that the contact disk 200 can be placed onto the second end of the electrode coil with the tabs, and the tabs then touch or electrically contact the first surface of the contact segments.

[0048] Figure 2D shows the cathode contact disk from Figure 2C with multiple welding arcs. The electrode coil 120 is welded to the contact disk 200 by applying the welding arcs 209 to a second surface 208 of the contact segments 201, 202, facing away from the first surface of the contact disk. Due to the partially circular contact segments (circular sections), the welding arcs 209 are partial arcs of a circle and are arranged at least partially concentrically around the center point 204. Furthermore, one or more welding arcs 209 can be closed to form a circle in the circular connection area 211.

[0049] Figures 3A to 3D show further embodiments of a contact disk for an electrochemical storage cell. Shown are flat, substantially circular contact disks 200, which can be used to contact an electrode coil 120, for example, a cylindrical round cell 100. The disks 200 are each shown in plan view and comprise two contact segments 201, 202, each forming a circular section of a contact disk 200. The contact segments 201, 202 are arranged symmetrically around the center point 204 of a contact disk 200. Between the contact segments 201, 202, regions 205, 206 are cut out of the contact disks 200, which also form circular sections. These regions are also arranged symmetrically around the center point of the contact disk.

[0050] The contact disk 200 in Figure 3A is an embodiment that can be used, for example, as an anode contact disk. For use in a cylindrical cell housing 110, the contact disk 200 is arranged, for example, in front of the contact plate 170. A valve (not shown) can be provided in the contact plate 170, which can be arranged in front of the central opening 207 and the winding core 190 to eject material from the cell interior.

[0051] In the embodiment shown in Figure 3A, the contact segments 201, 202 are connected to one another, in particular electrically conductively, by two outer arcs 212, 213. In other words, the contact segments 201, 202 and the outer arcs 212, 213 essentially form the contact disk 200. Furthermore, the contact disk 200 has a substantially circular central opening 207 centered around the center point 204. This central opening 207 is preferably larger than the winding core 190 of the electrode winding 120 to prevent material from blocking the opening in the event of a thermal safety event, thus allowing it to be more easily ejected from the central opening 207.

[0052] Figure 3B shows a similar embodiment, which differs from Figure 3A in that no central opening is provided. Instead, the contact segments 201, 202 are connected to each other by a central connecting region 210. This embodiment can be used, for example, as a cathode contact disk, thus complementing the contact disk of Figure 3A as an anode contact disk.

[0053] Figures 3C and 3D show embodiments corresponding to Figures 3A and 3B. The embodiments differ in that no outer arches are provided.

[0054] The embodiments of Figures 3A to 3D can be arranged on a carrier 211.

[0055] The presented contact disks 200 can be configured such that the contact segments 201, 202 form welding areas that correspond to the edge area of ​​the electrode coil 120. For example, tabs 150, 160 can be arranged on the edge area such that, in the assembled state of the round cell 100, they essentially only lie beneath the contact segments 201, 202. In this way, disk material can only be present in the welding area, and the functions of the contact disk 200 are separated. This creates a current path via the contact segments 201, 202 and a possible gas flow for degassing and ventilation via the recesses, i.e., the areas 205, 206 that are removed from the contact disk 200. Electrolyte filling is also possible via these areas 205, 206.

[0056] The shape of the disc can be interpreted as a BMW logo, thus serving to uniquely identify this company's battery cells. To prevent blockage of the inner material ejection opening of the electrode coil in the event of a thermal event, a central opening 207 of the contact disc 200 can be provided, allowing ventilation. The contact disc 200 can be welded to the cell housing (for example, with an outer edge of the disc). There are also "pizza-shaped" elements that can be connected or separated by the outer or inner edge. Blockage of ventilation can be avoided via the outer edge of the contact disc. For example, the contact segments can be welded to the housing from the outside.

[0057] Figure 4 shows a schematic and not to scale illustration of an electrode layer sequence 1 which, when wound up, forms the electrode coil 120. The drawing shows the layer structure 1 in a plan view. The electrode layer sequence 1 comprises an anode layer, a cathode layer, and a separator layer which electrically separates the anode layer and the cathode layer. The layers are stacked one on top of the other in a sequence which extends into the plane of the drawing and are therefore not shown in the plan view. It is understood that, due to the winding, a further separator layer (not shown) can be provided on the anode layer or on the cathode layer in order to ensure electrical separation of the anode layer and the cathode layer even when wound up in the electrode coil 120.

[0058] The electrode layer sequence 1 has a substantially rectangular basic shape and can be wound, i.e., rolled up, from a first longitudinal end 2 along the longitudinal direction (indicated by the arrow) to a second longitudinal end 3. The first longitudinal end 2 is then located on the winding core 190. The current collectors 150 and 160 each protrude in a transverse direction on opposite sides 4, 5 of the layer structure 1 from the respective electrode, so that the electrical connections described in connection with Figure 1 can be established. The edge region shown comprises a plurality of electrically conductive tabs 150, 160.

[0059] Figure 5 shows an exemplary embodiment of an edge region of the electrode layer sequence. The tabs (depending on the viewing direction of the anode or cathode current collectors 150, 160) are arranged in the electrode layer sequence 1 such that, when bent, they form regions 122 similar to the circular segments 201, 202. For example, the tabs are bent from the inside out so that they overlap. This results in a comparatively small area over which the tabs can be welded to the contact segments 201, 202. For example, an overlap typically results in 0.4 mm of a tab available for contacting and welding to the contact disk 200 (radial direction welding). With arc welding, a longer welding area can be achieved than with radial welding, which means low resistance and a lower chance of unwelded tabs.Although the improved concept has been illustrated and described in detail using exemplary embodiments, it is not limited by the exemplary embodiments. Rather, other variations of the improved concept may be derived therefrom by those skilled in the art without departing from the scope of protection defined by the claims.

[0060]

[0061] 1 Electrode layer sequence

[0062] 2 first longitudinal end

[0063] 3 second longitudinal end

[0064] 4 Page

[0065] 5 Page

[0066] 100 cylindrical electrochemical storage cells (round cells)

[0067] 110 housings

[0068] 120 electrode coils

[0069] 121 Marginal area

[0070] 122 area (with bent tabs)

[0071] 130 base plate

[0072] 140 electrical connection

[0073] 150 current arresters

[0074] 160 current arresters

[0075] 170 contact plate

[0076] 180 electrical connection

[0077] 190 winding core

[0078] 200 contact disc

[0079] 201 contact segment

[0080] 202 Contact segment

[0081] 203 sheets

[0082] 204 Center

[0083] 205 exempt area

[0084] 206 exempt area

[0085] 207 central opening

[0086] 208 area

[0087] 209 welding elbows

[0088] 210 connection area

[0089] 212 outer arch

[0090] 213 Outer arch

Claims

1. A method for producing an electrochemical storage cell, comprising the steps of: - Providing a flat, substantially circular contact disc (200) with at least two contact segments (201, 202), each forming a circular section of the contact disc (200) and arranged symmetrically around the center point (204) of the contact disc (200), and wherein circular sections (205, 206) are cut out of the contact disc (200) between the contact segments (201, 202) and arranged symmetrically around the center point (204) of the contact disc (204), - arranging an electrode coil (190) in a cylindrical cell housing (110), wherein the electrode coil (190) comprises an electrode layer sequence (1), - contacting the electrode winding (190) by bringing an edge region of the electrode layer sequence into contact with a first surface of the contact segments (201, 202) of the contact disc (200), and - welding the electrode coil (190) to the contact disc by applying welding arcs (209) to a second surface (208) of the contact segments (201, 202) facing away from the first surface of the contact disc (200), the welding arcs (209) being arranged at least partially concentrically around the center point (204).

2. The method according to claim 1, wherein - the electrode coil (190) is formed by winding the electrode layer sequence (1) into a cylinder, - the electrode layer sequence (1) with the perpendicular to the electrode layer sequence (1) oriented first surface of the contact disk (200), wherein the electrode layer sequence (1) comprises a contacting region (150, 160) which - for example before winding - is bent, in particular bent by 180°, such that the contacting region (150, 160) thus bent contacts the first surface and is welded to the contact disk (200).

3. The method according to any one of the preceding claims, wherein - the contact disc (200) is welded to a first end of the electrode coil (1) and a further contact disc (200) is welded to a second end of the electrode coil (1) opposite the first end; wherein: - the contact disc (200) has an opening (207) in the region of the center point (204), and - the further contact disc (200) has a continuous connecting region (210) between the contact segments (201, 202) of the contact disc (200) in the region of the center point (204).

4. The method according to any one of the preceding claims, wherein - the contacting area (150, 160) comprises conductive tabs, each of which is bent - for example before winding and in particular by 180° - so that the conductive tabs contact the first surface of the contact disc (200), and - the bent tabs are welded to the contact disc (200).

5. The method according to one of the preceding claims, wherein the conductive tabs are arranged in the contacting region such that the bent tabs contact the contact disk (200) only in the region of the contact segments (201, 202).

6. An electrochemical storage cell comprising: - a cylindrical cell housing (110) and an electrode coil (190) arranged in the cylindrical cell housing, wherein the electrode coil (190) comprises an electrode layer sequence (1), - a flat, substantially circular contact disc (200) with at least two contact segments (201, 202), each forming a circular section of the contact disc (200) and arranged symmetrically around the center point (204) of the contact disc (200), and wherein circular sections (205, 206) are cut out of the contact disc (200) between the contact segments (201, 202) and arranged symmetrically around the center point (204) of the contact disc (200); wherein the electrode coil (190): - is in electrically conductive contact with a first surface of the contact segments (201, 202) of the contact disc (200) via an edge region (150, 160) of the electrode layer sequence (1), and - the contact disc (200) is provided with welding arcs (209) on a second surface (208) of the contact segments (201, 202) facing away from the first surface of the contact disc (200), the welding arcs (209) being arranged at least partially concentrically around the center point (204).

7. The electrochemical storage cell according to claim 6, wherein - the contact segments (201, 202) of the circular contact disc (200) are connected to one another, or - the contact segments (201, 202) of the circular contact disc (200) are each separate from one another.

8. The electrochemical storage cell according to any one of the preceding claims, wherein - the electrode layer sequence (190) is wound into a cylinder and thus forms a cylindrical electrode coil, and - the electrode layer sequence (1) is welded to the first surface of the contact disc (200) oriented at right angles to the electrode layer sequence (1) in an electrically conductive manner in contact with the contact disc (200).

9. The electrochemical storage cell according to any one of the preceding claims, wherein - the electrode layer sequence (1) comprises a contacting region (150, 160), is bent, in particular by 180°, and - the contact area (150, 160) thus bent is welded to the contact disc (200).

10. The electrochemical storage cell according to any one of the preceding claims, wherein - the contacting area (150, 160) comprises conductive tabs which are bent over, and - the bent tabs are welded to the contact disc (200).

11. The electrochemical storage cell according to one of the preceding claims, wherein the conductive tabs are arranged in the contacting region (150, 160) such that the bent tabs contact the contact disk (200) only in the region of the contact segments (201, 202).

12. The electrochemical storage cell according to any one of the preceding claims, wherein - the contact disc (200) has an opening (207) in the region of the center point (204) or - the contact disc (200) has a continuous connection area between the contact segments of the contact disc in the area of ​​the center point (204).

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