Energy storage battery and manufacturing method

Abstract

An energy storage battery (100) is known that includes a composite (104) in the form of a cylindrical winding composed of strip-shaped electrodes and separators and having two end faces (104b, 104c) and a winding casing (104a) disposed therebetween. The electrodes each have a current collector (115, 125) and are arranged in the composite so that they are offset relative to each other, such that the long edge of the negative electrode protrudes from one of the end faces (104b, 104c) and the long edge of the positive electrode protrudes from the other end face. The composite (104) is axially oriented within a housing that includes a tubular metal housing section (101) having a circular opening (101c) at its end, such that the winding casing (104a) rests against the inner surface (101b) of the tubular housing section (101). To electrically contact one of the electrodes, the battery (100) includes a contact element (110) that is in direct contact with one of the long edges (115a, 125a) protruding from one end face and is connected to this long edge, preferably by welding. According to the invention, the contact element (110) used is a contact element with a circular edge (110a), an annular seal (103) made of an electrically insulating material is fitted onto the circular edge (110a) of the contact element (110), and a circular opening (101c) at the end of the tubular housing part (101) is closed by the contact element (110).

Description

[Technical Field]

[0001] The present invention, as described below, relates to an energy storage battery including an electrode-separator assembly. [Background technology]

[0002] Electrochemical cells can convert stored chemical energy into electrical energy through oxidation-reduction reactions. They generally include positive and negative electrodes separated from each other by a separator. During discharge, electrons are released at the negative electrode as a result of the oxidation process. This generates an electron current that can be drawn by an external power-consuming device in which the electrochemical cell acts as an energy supplier. Simultaneously, an ionic current corresponding to the electrode reaction is generated within the cell. This ionic current passes through the separator and is enabled by an ion-conducting electrolyte.

[0003] A battery is called a secondary battery if its discharge is reversible, meaning that the conversion from chemical energy to electrical energy during discharge can be reversed, thus allowing the battery to be recharged. The conventional designations in secondary batteries, the anode (negative electrode) and cathode (positive electrode), refer to the discharge function of the electrochemical cell.

[0004] Secondary lithium-ion batteries are used for many applications today because they can provide high current and stand out for their relatively high energy density. They are based on the use of lithium, which can travel back and forth between the battery electrodes in the form of ions. The negative and positive electrodes of a lithium-ion battery are typically formed from what are known as composite electrodes, which include electrochemically inert components in addition to electrochemically active components.

[0005] Useful electrochemical active materials for secondary lithium-ion batteries are, in principle, any material capable of absorbing and releasing lithium ions. In many cases, carbon-based particles, such as graphitic carbon, are used for the negative electrode. Other non-graphitic carbons suitable for lithium intercalation may also be used. In addition, metallic and metalloid materials that can alloy with lithium are also available. For example, elements such as tin, aluminum, antimony, and silicon can form metallic interphases with lithium. Examples of active materials that can be used for the positive electrode include lithium cobalt oxide (LiCoO2), lithium manganese oxide (LiMn2O4), lithium iron phosphate (LiFePO4), or derivatives thereof. Electrochemical active materials usually exist in the electrode in the form of particles.

[0006] As electrochemically inert components, composite electrodes generally include two-dimensional current collectors and / or band-shaped current collectors, such as metal foils that serve as carriers for their respective active materials. The current collector for the negative electrode (anode current collector) can be formed from, for example, copper or nickel, and the current collector for the positive electrode (cathode current collector) can be formed from, for example, aluminum. In addition, the electrodes may include electrode binders (e.g., polyvinylidene fluoride (PVDF) or other polymers, such as carboxymethylcellulose), conductivity-enhancing additives, and other additives as electrochemically inert components. The electrode binder also ensures the mechanical stability of the electrodes and, in many cases, the adhesion of the active material to the current collector.

[0007] Lithium-ion batteries generally contain a solution of a lithium salt, such as lithium hexafluoride phosphate (LiPF6), in an organic solvent (e.g., ethers and esters of carbonates) as the electrolyte.

[0008] In the manufacture of lithium-ion batteries, composite electrodes are combined with one or more separators to form a composite. In this case, the electrodes and separators are usually joined to each other under pressure, either selectively or by lamination or adhesive bonding. By impregnating the assembly with electrolyte, the basic capability for the battery to function can be established.

[0009] In many embodiments, the composite is formed as a wound body or processed to give a wound body. Generally, it includes the following arrangement: positive electrode / separator / negative electrode. Often, the composite is manufactured as a bicell, having the following possible arrangements: negative electrode / separator / positive electrode / separator / negative electrode or positive electrode / separator / negative electrode / separator / positive electrode.

[0010] Applications in the automotive sector, electric bicycles, or other applications with high energy requirements in vehicles, for example, require lithium-ion batteries with maximum energy density that simultaneously possess the ability to handle high currents during charging and discharging. Often, batteries for the aforementioned applications take the form of a circular cylindrical battery with a shape factor of, for example, 21 × 70 (diameter × height in mm). This type of battery always includes a composite in the form of a wound body. Modern lithium-ion batteries of this form factor can already achieve an energy density of up to 270 Wh / kg. However, this energy density is considered merely an intermediate stage. The market is already demanding batteries with even higher energy densities.

[0011] However, in the development of improved electrochemical cells, energy density is not the only factor to consider. Crucial parameters are the battery's internal resistance and the thermal coupling of the electrodes, which can be important for regulating the battery temperature, and must be kept to a minimum to reduce power loss during charging and discharging. These parameters are also extremely important for circular cylindrical batteries, which involve complexes in the form of wound bodies. During rapid charging of a battery, power loss can lead to heat generation within the battery, which can cause severe thermomechanical stress, and therefore deformation and damage to the battery structure. The risk increases when the electrical coupling of the current collector is via separate electrical output conductor lugs welded to the current collector, emerging axially from the wound complex, because under heavy loads during charging or discharging, heating can occur locally within these output conductor lugs.

[0012] International Publication No. 2017 / 215900A1 describes an electrode-separator assembly and a battery in which the electrodes are band-shaped and in the form of a wound body. Each electrode has a current collector on which the electrode material is mounted. Electrodes of opposite polarity are arranged offset from each other in the electrode-separator assembly such that the longitudinal edge of the current collector of the positive electrode protrudes from the wound body on one side, and the longitudinal edge of the current collector of the negative electrode protrudes on the other side. For electrical contact connection of the current collectors, the battery has at least one contact element lying in contact with one of the longitudinal edges to give rise to a linear contact zone. The contact element is joined to the longitudinal edge along the linear contact zone by welding. This also allows for electrical contact with the current collector and therefore the corresponding electrode along its entire length. This greatly reduces the internal resistance in the battery described above. As a result, the generation of high currents can be managed much better.

[0013] U.S. Patent No. 6,432,574,B1 discloses a cylindrical round cell in which an electrode-separator assembly, similarly in the form of a wound body, is electrically contacted via contact plates welded to the end faces. Figure 2A shows a typical housing for such an electrode-separator assembly. It includes a cup-shaped housing portion in which the wound electrode-separator assembly is axially aligned. The housing is closed by a multi-part cover, on which an annular seal is fitted over its edge. To seal the housing, the end edge of the cup is folded radially inward to cover the edge of the cover and the seal fitted over it. To facilitate this process, a deep circumferential groove is required just beneath the cover. During the sealing operation, a tool is engaged so that axial pressure can be applied from above and below to the edge of the cover and the seal as the end edge is folded back. As a result, the seal is compressed, here between the groove and the lower surface of the edge of the cover and between the periphery of the cup and the upper surface of the edge of the cover, which results in an efficient seal. However, the required groove presents disadvantages. Firstly, it must be introduced into the housing in a separate step after the electrode-separator assembly has been inserted. Secondly, the groove requires wasted volume that must be overcome using a conductor to establish electrical contact with the cover. In the case of the battery shown in Figure 2A, for this purpose, an extra-long contact sheet is welded to the upper end surface, folded over, and welded to the inner surface of the cover.

[0014] European Patent Application Publication No. 2924762A2 discloses a cylindrical circular battery in which the edges of electrodes on a cylindrical electrode-separator assembly in the form of a wound body are contacted using a contact sheet having a 90° folded edge region so that the edges can lie flat against the inner wall of the battery housing. Two perimeter beads are introduced into the battery housing. One bead serves to press the battery housing directly onto the contact sheet. The other bead serves to seal the battery housing, compressing a seal ring fitted over one edge of the contact sheet. [Overview of the project] [Problems that the invention aims to solve]

[0015] The present invention aims to provide an energy storage cell that stands out from the prior art in its improved energy density and uniform current distribution over the maximum area and length of its electrodes, while simultaneously possessing superior characteristics in terms of its internal resistance and passive cooling properties. In addition, the battery may also feature improved manufacturability and safety. [Means for solving the problem]

[0016] This objective is achieved by an energy storage battery having the features of claim 1, as described below, in particular a preferred embodiment of the energy storage battery described below, and by a process having the features of claim 12, as described below, in particular a preferred embodiment of the process described below. Preferred configurations of the battery and process will also become apparent from the dependent claims.

[0017] The energy storage battery of the present invention always has the following features a. to j.: a. The battery includes an electrode-separator assembly having an anode / separator / cathode arrangement. b. The electrode-separator assembly takes the form of a cylindrical winding having two end faces and an intermediate winding shell. c. The battery includes a housing that includes a metal tubular housing portion having a circular opening at the end. d. Within the housing, the electrode-separator assembly, which takes the form of a wound body, is aligned axially such that the wound body shell is adjacent to the inner surface of the tubular housing portion. e. The anode is band-shaped and includes a band-shaped anode current collector having a first longitudinal edge, a second longitudinal edge, and two end portions. f. The anode current collector includes a strip-shaped main region on which a layer of the negative electrode material is placed, and a free-edge strip that extends along the first longitudinal edge and on which no electrode material is placed. g. The cathode is band-shaped and includes a band-shaped cathode current collector having a first longitudinal edge, a second longitudinal edge, and two end portions. h. The cathode current collector includes a strip-shaped main region on which a layer of the positive electrode material is placed, and a free-edge strip that extends along the first longitudinal edge and on which no electrode material is placed. i. The anode and the cathode are arranged in the electrode-separator assembly such that the first longitudinal edge of the anode current collector protrudes from one of the end faces, and the first longitudinal edge of the cathode current collector protrudes from the other of the end faces. j. The battery includes at least a partially metallic contact element that is in direct contact with one of the first longitudinal edges and is preferably connected to this longitudinal edge by welding.

[0018] Selection of Preferred Embodiments of the Electrochemical System In principle, the present invention includes an energy storage battery regardless of their electrochemical configuration. However, in a particularly preferred embodiment, the energy storage battery of the present invention is a lithium-ion battery, particularly a secondary lithium-ion battery. Therefore, in principle, it is possible to use all electrode materials known for secondary lithium-ion batteries for the anode and cathode of the energy storage battery.

[0019] The active material used in the negative electrode of the energy storage battery of the present invention in the form of a lithium-ion battery can preferably be carbon-based particles such as graphite-based carbon or non-graphite-based carbon materials having the ability to intercalate lithium, also in the form of particles. Alternatively or in addition, lithium titanate (Li4Ti5O 12) Or its derivatives can also be present in the negative electrode, preferably also in the form of particles. In addition, the negative electrode can optionally contain, as an active material, at least one material from the group of silicon, aluminum, tin, antimony or lithium, which can reversibly intercalate and deintercalate lithium, in the form of a compound or alloy of these materials, such as silicon oxide, in combination with a carbon-based active material. Tin, aluminum, antimony and silicon can form intermetallic phases with lithium. The capacity for lithium absorption here, especially in the case of silicon, exceeds several times that of graphite or equivalent materials.

[0020] For the positive electrode of the energy storage battery of the present invention in the form of a lithium-ion battery, examples of useful active materials include lithium-metal oxide compounds and lithium-metal phosphate compounds such as LiCoO2 and LiFePO4. Highly suitable is lithium nickel x Mn y Co z O2 (where x + y + z is usually 1), lithium nickel manganese cobalt oxide (NMC), lithium manganese spinel (LMO) having the molecular formula LiMn2O4 or lithium nickel x Co y Al z O2 (where x + y + z is usually 1), lithium nickel cobalt aluminum oxide (NCA). Derivatives of these, such as the empirical formula Li 1.11 (Ni 0.40 Mn 0.39 Co 0.16 Al 0.05 ) 0.89 O2, lithium nickel manganese cobalt aluminum oxide (NMCA) or Li 1+x M-O compounds and / or mixtures of the substances mentioned can also be used. The cathode active material is also preferably used in particulate form.

[0021] In addition, the electrodes of the energy storage battery of the present invention in the form of a lithium-ion battery preferably contain an electrode binder and / or additives for improving conductivity. The active material is preferably incorporated into the matrix of the electrode binder, and adjacent particles within the matrix preferably come into direct contact with each other. The conductive agent plays a role in increasing the conductivity of the electrode. Typical electrode binders are, for example, based on polyvinylidene fluoride (PVDF), polyacrylate, or carboxymethylcellulose. Typical conductive agents are carbon black and metal powders.

[0022] The energy storage battery of the present invention preferably comprises an electrolyte, and in the case of a lithium-ion battery, an electrolyte based on at least one lithium salt, such as lithium hexafluoride phosphate (LiPF6) dissolved in an organic solvent (e.g., a mixture of organic carbonates or a cyclic ether such as THF or a nitrile). Other usable lithium salts include, for example, lithium tetrafluoroborate (LiBF4), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium bis(fluorosulfonyl)imide (LiFSI), and lithium bis(oxalate)borate (LiBOB).

[0023] Selection of separators and preferred embodiments The electrode-separator assembly preferably includes at least one band-shaped separator having or having first and second longitudinal edges and two end portions, preferably two band-shaped separators.

[0024] The separator is preferably formed from an electrically insulating polymer film. It is preferable that the separator be permeable to the electrolyte. For this purpose, the polymer film used may, for example, have micropores. The film may consist of, for example, polyolefin or polyetherketone. Nonwoven or woven fabrics or other electrically insulating sheet-like structures made of polymer materials can also be used as separators. It is preferable to use a separator having a thickness in the range of 5 μm to 50 μm. Depending on the embodiment, the separator of the assembly may also be one or more layers of the solid electrolyte.

[0025] Preferred structure of electrode-separator assembly in the form of a wound body In an electrode-separator assembly in the form of a wound body, the band-shaped anode, band-shaped cathode, and band-shaped separator preferably take the form of a spiral wound body. To manufacture the electrode-separator assembly, the band-shaped electrode is fed together with the band-shaped separator to a winding device and preferably wound spirally around a winding axis inside it. In some embodiments, the electrode and separator are wound for this purpose on a cylindrical or hollow cylindrical winding core placed on a winding mandrel and remain in the wound body after the winding operation. The wound body shell may be formed, for example, from a polymer film or adhesive tape. The wound body shell may also be formed from one or more separator wound bodies.

[0026] Selection of current collector and preferred embodiment The current collector of the energy storage battery plays the role of making electrical contact with the electrochemically active components present in each electrode material over the maximum possible area. The current collector is preferably made of a metal or at least metallized on its surface. In the case of the energy storage battery of the present invention in the form of a lithium-ion battery, suitable metals for the anode current collector are, for example, copper or nickel or other conductive materials, in particular copper alloys and nickel alloys or nickel-plated metals. Stainless steel is also useful in principle. In the case of the energy storage battery of the present invention in the form of a lithium-ion battery, suitable metals for the cathode current collector are, in particular aluminum or other conductive materials, including aluminum alloys.

[0027] The anode current collector and / or cathode current collector are preferably metal foils having a thickness in the range of 4 μm to 30 μm, and more particularly band-shaped metal foils having a thickness in the range of 4 μm to 30 μm.

[0028] However, in addition to foil, the current collector used may also be other band-shaped substrates such as metal, metallized nonwoven fabric, open-pore metal foam, or expanded metal.

[0029] Preferably, the current collector has electrode materials mounted on both sides.

[0030] It is preferable that the longitudinal edge of the separator forms the end face of the electrode-separator assembly in the form of a wound body.

[0031] The longitudinal edges or protrusions from the end faces or surfaces of the edges of the anode current collector and / or cathode current collector that protrude from the end face or surface of the winding body or stack are preferably 5000 μm or less, more preferably 3500 μm or less.

[0032] More preferably, the protrusion of the edge or longitudinal edge of the anode current collector from the stack surface or the end face of the winding is 2500 μm or less, more preferably 1500 μm or less. More preferably, the protrusion of the edge or longitudinal edge of the cathode current collector from the stack surface or the end face of the winding is 3500 μm or less, more preferably 2500 μm or less.

[0033] Solution of the invention The specific characteristics of an energy storage battery are the following three features k., l., and m.: k. The contact element includes a circular edge. l. The battery includes an annular seal made of an electrically insulating material that surrounds the circular edge of the contact element. m. The contact element, together with the seal, closes the circular end opening of the tubular housing portion.

[0034] Therefore, proposed in accordance with the present invention is the use of a contact element having a circular rim, the fitting of an annular seal made of an electrically insulating material onto the circular rim of the contact element, and the closure of the terminal circular opening of the tubular housing portion by the contact element. The contact element serves solely for the electrical contact of the electrodes, instead, it also functions as a housing portion at the same time. This is associated with a great advantage in that a separate electrical connection between the contact element and the housing portion is no longer required. This creates space within the housing and simplifies the battery assembly. Furthermore, the direct connection of the housing portion to the battery's current collector gives it excellent cooling properties.

[0035] The contact element is preferably a disc-shaped contact sheet. More preferably, the disc-shaped contact sheet has either a single-layer edge extending radially outward or an edge that is folded inward, thereby resulting in a two-layer edge region having a U-shaped cross-section.

[0036] Preferred Embodiment of Electrical Connection of Contact Element to Electrode-Separator Assembly in the Form of Contact Element / Wound Body In a first particularly preferred variant of the present invention, the energy storage battery has at least one of the following four features a. to d.: a. The contact element is a metal disk, or includes a metal disk, the edge of which corresponds to or forms a portion of the circular edge of the contact element. b. Contact elements, particularly metal discs, are positioned within the tubular housing portion such that the annular seal extends along the periphery contact zone on the inner surface of the tubular housing portion. c. The annular seal is compressed within the contact zone as a result of pressure applied to it by the edges of the contact elements, particularly the edges of the metal disk and the inner surface of the tubular housing portion. d. One of the first longitudinal edges is directly adjacent to a contact element, particularly to a metal disk, and is preferably joined to the contact element, particularly the disk, by welding.

[0037] It is particularly preferable to implement the preceding features a., b., and d. in combination. In one evolved form, all four preceding features a. to d. are implemented in combination with each other. In the simplest embodiment, the metal disk is a flat part of sheet metal having a circular periphery extending in only one plane. However, more complex forms can often be preferred. For example, the metal disk may be shaped to have one or more circular depressions and / or ridges around its center, preferably concentrically arranged, which may result in a corrugated cross-section, for example. It is also possible that its inner surface has one or more lands. In addition, the disk may have a radially folded edge, thereby having a two-layered edge region, for example, having a U-shaped cross-section.

[0038] The contact element may consist of multiple individual parts, including a metal disc, which does not necessarily have to be made entirely of metal. In a particularly preferred embodiment, the contact element may include, for example, a shaped metal terminal cover which may be welded onto the metal disc and has a circular periphery having approximately or exactly the same diameter as the metal disc, so that the edges of the metal disc and the edges of the terminal cover collectively form the edge of the contact element. In a further embodiment, the edge of the terminal cover may be surrounded by the edges of the metal disc described above which are bent radially inward. In a preferred embodiment, a clamp connection may even be present between the two individual parts.

[0039] To allow the annular seal to extend along the circumferential contact zone on its inner surface, it is preferable that the tubular housing portion has a circular cross-section, at least in the region adjacent to the seal. Preferably, the region is in the form of a hollow cylinder for this purpose. The inner diameter of the tubular housing portion in this region matches the outer diameter of the edge of the contact element, in particular the outer diameter of the metal disk on which the seal is fitted.

[0040] The compression of the seal within the contact zone is a feature not found in the prior art described at the beginning. While the seal in the battery described in U.S. Patent No. 6,432,574,B1 is compressed above and below the edge of the cover, the compression seal region according to the present invention described here preferably extends concentrically around the edge of the cover.

[0041] The seal itself can be a conventional polymer seal that must be chemically resistant to the electrolyte used in each case. Those skilled in the art are aware of suitable sealing materials.

[0042] The concept of welding the edge of a current collector to a contact sheet element is already known from International Publication No. 2017 / 215900A1 or Japanese Patent Publication No. 2004-119330. This technique enables particularly high current endurance and low internal resistance. Therefore, for methods of electrical connection of contact elements, especially disc-shaped contact elements, to the edge of a current collector, refer fully to the contents of International Publication No. 2017 / 215900A1 and Japanese Patent Publication No. 2004-119330.

[0043] In particular, for welding a metal disc to the longitudinal edge of a current collector, which results in an inherently more reliable electrical connection than a simple press-fit contact, it is especially preferable that the metal disc has at least one of the following features a. and b.: a. The metal disc used has a thickness preferably in the range of 50 μm to 600 μm, and preferably in the range of 150 μm to 350 μm. b. The metal disc is made of alloy or non-alloy aluminum, alloy or non-alloy titanium, alloy or non-alloy nickel, or alloy or non-alloy copper, but optionally also made of stainless steel (e.g., of type 1.4303 or 1.4404) or nickel-plated steel. It is particularly preferable if the preceding features a. and b. are implemented in combination.

[0044] When the longitudinal edge directly adjacent to the metal disk is the anode current collector, the anode current collector and the metal disk, particularly the metal disk welded thereto, are preferably both made of the same material or at least chemically related materials, such as copper and copper alloys. In the case of the energy storage battery of the present invention in the form of a lithium-ion battery, it is preferably selected from the group including copper, nickel, titanium, alloys of these three elements, nickel-plated steel, and stainless steel. In the case of a lithium titanate anode, the anode current collector and / or metal disk may also be made of aluminum.

[0045] When the longitudinal edge directly adjacent to the metal disk is the cathode current collector, the cathode current collector and the metal disk, particularly the metal disk welded thereto, are preferably both made of the same material or at least chemically related materials, such as aluminum and aluminum alloys. This is more preferably selected from the group including alloyed or non-alloyed aluminum, titanium, titanium alloys, and stainless steel (e.g., type 1.4404).

[0046] More preferably, one of the first longitudinal edges is directly adjacent to the metal disk with respect to its length. This creates a linear contact zone with a spiral progression in the case of a spirally wound electrode. It is preferable that a very uniform connection of the longitudinal edge to the metal disk exists along this linear, and preferably spiral, contact zone using a suitable weld bond. More preferably, this connection may be configured as follows: The longitudinal edge of the current collector directly adjacent to the metal disk is continuously joined to the metal disk via a welded joint along its entire length. The longitudinal edges of the current collectors directly adjacent to the metal disk include one or more sections that are continuously connected to the metal disk via welded seams along their entire length. More preferably, these sections have a minimum length of 5 mm, preferably 10 mm, and more preferably 20 mm. The longitudinal edge of the current collector directly adjacent to the metal disk is connected to the metal disk via numerous spot welds (called multi-pin bonds). Of course, among these three variations of contact, it is also possible to combine the second and third ones with each other.

[0047] In one possible development of the second variation of contact, the sections bonded to the metal disk over their entire length extend over at least 25%, preferably at least 50%, and more preferably about 75%, of the total length of their respective longitudinal edges.

[0048] In a second particularly preferred variation of the present invention, the energy storage battery has at least one of the following five features a. to e.: a. The contact element includes a metal disk, the edge of which corresponds to or forms a portion of the circular edge of the contact element. b. The metal disc is positioned within the tubular housing portion such that the annular seal extends along the periphery contact zone on the inner surface of the tubular housing portion. c. The annular seal is compressed within the contact zone as a result of the pressure applied to it by the edge of the metal disc and the inner surface of the tubular housing portion. d. The contact element includes a metal contact sheet having two surfaces, one of which faces the direction of the metal disk and is preferably joined to the metal disk by welding. e. One of the first longitudinal edges is directly adjacent to the other surface of the contact sheet and is preferably joined to it by welding. It is particularly preferable to combine the preceding features a., b., c., and d. In one developmental form, all five preceding features a. to e. are combined and implemented.

[0049] With respect to some features, the second particularly preferred modification of the present invention is no different from the first, for example, within the scope of features b. and c., and therefore those features should no longer be implemented separately. However, in contrast to the first particularly preferred modification of the present invention, the contact element and metal disk include a contact sheet as a further component, in which case one of the first longitudinal edges does not directly adjoin the metal disk but instead directly adjoins the contact sheet. The metal disk serves to close the housing while the contact sheet contacts the longitudinal edge of the current collector. The longitudinal edge is preferably connected here to the contact sheet according to one of the three contact modifications described above.

[0050] From a physical standpoint, the contact sheet is preferably formed in the same manner as the metal disc in the first particularly preferred modification of the present invention. In other words, it is preferably made of the same material as the adjacent current collector or a chemically related material. It is preferably in the range of 50 μm to 600 μm, preferably 150 μm to 350 μm.

[0051] In a simple embodiment, the contact sheet is a two-dimensional sheet metal component that extends in only one plane, while in other embodiments, it may be a shaped sheet metal component. Specifically, it may have one or more lands or elongated recesses on the side in contact with the longitudinal edge.

[0052] The contact sheet may have a circular periphery, but this is by no means an absolute requirement. Depending on the circumstances, the contact sheet may be, for example, a metal strip, or may have multiple segments in the form of a strip, for example, arranged in a star shape.

[0053] Depending on the embodiment, a contact sheet having at least one slot and / or at least one perforation may be used. These can serve to counteract the deformation of the contact sheet when forming a weld bond with the first longitudinal edge.

[0054] On the side of the contact sheet facing the metal disk, preferably, when the metal disk is in direct contact with the contact sheet, a two-dimensional contact area exists, i.e., the contact sheet and the metal disk lie flat against each other in at least a portion of the area. The existence of this direct contact and two-dimensional contact surface is preferred.

[0055] The metal disc is preferably formed to complement it. It preferably also has a thickness in the range of 50 μm to 600 μm. When combined with the contact sheet, it may be made of, for example, type 1.4303 or 1.4404 stainless steel.

[0056] The contact sheet and the metal disc are preferably in rigid contact with each other, and more preferably in rigid direct contact. In this case, they are more preferably fixed to each other by welding or soldering.

[0057] In a particularly preferred embodiment, the contact sheet is designed as a contact plate as described in International Publication No. 2017 / 215900A1.

[0058] Closure of the terminal circular opening - Preferred configuration More preferably, the energy storage batteries described in particular the first and second particularly preferred modified embodiments of the present invention have at least one of the following two further features a. and b.: a. The tubular housing portion includes, in the axial direction, a central section adjacent to the inner surface of the wound shell and a contact section adjacent to the inner surface of the annular seal, where - The tubular housing portion has a constant inner diameter within and between the two sections, and / or - The central section is separated from the contact section by a recess that circularly surrounds the outer surface of the tubular housing portion. b. Within the surrounding recessed area, the outer diameter of the tubular housing portion is reduced by no more than 2 to 6 times the wall thickness of the housing within that area. It is particularly preferable that the recess separates the central section from the contact section.

[0059] According to the above description of preferred configurations of the tubular housing portion within the contact zone, the contact section is preferably cylindrical or more precisely hollow cylindrical. The same applies to the configuration of the central section.

[0060] The aforementioned recess is preferably a peripheral bead that may appear as a result of manufacturing, but unlike grooves introduced into the housing in the case of conventional batteries (see the above explanation relating to International Publication No. 2017 / 215900A1), it is by no means a requirement for closing the housing. Therefore, it preferably also has a much smaller depth than the aforementioned groove. In the ideal case, the bead is so negligible that its presence does not affect the inner diameter of the tubular housing portion, thereby it is constant from the central section to the contact section. This has the great advantage that there is no corresponding wasted volume resulting from the groove, and the central section can be closer to the contact section. In other words, it is possible to implement a higher winding body composed of electrodes and separators, and thus increase the energy density of the energy storage battery. In particular, in combination with the features of the first particularly preferred modification of the present invention described above, a further advantage is that it is possible to eliminate a separate current conductor for bridging the distance between the winding body and the housing cover.

[0061] In some embodiments of the present invention, it is even more preferable that the energy storage battery has at least one of the following two further features a. and b.: a. The tubular housing portion includes a circular edge that is surrounded by a seal and is bent radially inward around the edge of the contact element that secures the contact element within the circular opening of the tubular housing portion. b. The contact section extends axially from the recess to the edge that is bent radially inward. Feature a is a preferred development for all the embodiments described above, while feature b is relevant only when the bead described above occurs.

[0062] Modified housing with housing cup In a particularly preferred embodiment of the present invention, the energy storage battery has at least one of the following further features a. and b.: a. The tubular housing portion is the part of the housing cup that includes the circular base. b. The other end of the first longitudinal edge is directly adjacent to the base and preferably joined to the base by welding. It is particularly preferable to combine the features a. and b. described above.

[0063] The use of housing cups has long been known in the construction of battery housings, for example, from the International Publication No. 2017 / 215900A1 quoted at the beginning. In contrast, what is unknown is the direct connection of the longitudinal edge of the current collector to the base of the housing cup, as proposed here. This approach eliminates the separate electrical conductor now located on the base side and allows the use of an axially extended wound electrode-separator assembly, thus contributing to an increase in the energy density and improved cooling characteristics of the battery of the present invention.

[0064] According to the present invention, it is therefore preferable that the current collector edges of the positive and negative electrodes protruding from opposite end faces of the wound electrode-separator assembly be directly coupled to the housing portion, i.e., the base of the cup and the aforementioned contact elements which function as closing elements. Thus, the use of the available internal volume of the battery housing for the active components approaches its theoretical optimality.

[0065] The bonding of the other end of the first longitudinal edge to the base essentially follows the same construction principle as in the case of the contact element. Here again, the longitudinal edge is preferably directly adjacent to the base with respect to its length, thereby creating a linear contact zone having a spiral progression in the case of a spirally wound electrode. Here again, it is even more preferable that a very uniform bonding of the longitudinal edge to the metal disk exists along this linear and preferably spiral contact zone using a suitable weld bond. This bonding is preferably configured according to one of the three modifications of contact described above or a combination of these modifications, i.e., as a multi-pin bond.

[0066] The housing cup, particularly in the area of ​​its base, preferably has a thickness similar to that of the metal disk described above, i.e., specifically in the range of 50 μm to 600 μm, preferably in the range of 150 μm to 350 μm.

[0067] In particular, when the battery of the present invention is configured as a lithium-ion battery, the selection of the material from which the housing cap is made depends on whether the anode current collector or the cathode current collector is connected to the base. In principle, the preferred material is the same as the material from which the current collector itself is made. The materials described above are also useful for the metal disk.

[0068] In principle, as with the contact element, it is also possible that only an indirect connection exists between the other longitudinal edge of the first longitudinal edge and the base of the cup via a contact sheet. In this case, preferably, a weld bond exists between the longitudinal edge and the contact sheet according to one of the three modifications of contact described above, while the contact sheet is preferably joined to the base by direct welding. The contact sheet is preferably configured as its counterpart in the case of the contact element described above.

[0069] Modified housing with two covers In a further particularly preferred embodiment of the present invention, the energy storage battery has at least one of the following three further features a. to c.: a. The tubular housing portion has a further circular opening at the end. b. The battery includes a closure element having a circular rim that closes this further terminal opening. c. A closure element for a further terminal opening is a metal disk, or includes a metal disk, the edge of which corresponds to or forms a portion of the circular edge of the metal closure element. It is particularly preferable to combine the features a. to c. described above.

[0070] In this embodiment, the tubular housing portion replaces the housing cup together with the closing element. Therefore, the housing consists of three housing portions: one is tubular, and the other two (contact element and closing element) act as covers, closing the end opening of the tubular portion. With regard to manufacturing, this offers an advantage because, unlike the case of the housing cup, deep drawing tools are not required for the manufacture of the tubular housing portion. In the case of direct connection of the other end of the first longitudinal edge to the closing element, this offers essentially the same advantages as the aforementioned connection to the base of the housing cup.

[0071] The tubular housing portion in this embodiment is preferably cylindrical or hollow cylindrical. The closing element, similar to the contact element described above, in the simplest embodiment is a shaped metal disk having a circular periphery, for example a metal disk extending only in one plane, or alternatively a corrugated cross section, for example, one or more circular depressions and / or ridges around its center, preferably concentrically arranged. Similarly preferably, the inner surface of the closing element, particularly a metal disk, may have one or more lands. In addition, the closing element, particularly a metal disk, may also have a radially bent edge, thereby having, for example, a two-layered edge region with a U-shaped cross section.

[0072] More preferably, the contact element is a disc-shaped contact sheet. More preferably, the disc-shaped contact sheet has either a single-layer edge extending radially outward or an edge that is folded inward, thereby giving rise to a two-layer edge region having a U-shaped cross-section.

[0073] In selecting the material and preferred thickness of the closing element, particularly the metal disk, it is equally possible to refer to the above description of the metal disk of the closing element. The preferred characteristics specified therein are also applicable to the closing element.

[0074] In this particularly preferred embodiment, the energy storage battery has at least one of the following features a. to c.: a. The metal disc is positioned within the tubular housing portion such that its edge extends along the peripheral contact zone on the inner surface of the tubular housing portion. b. The edge of the metal disc is joined to the tubular housing portion via a surrounding welded joint. c. The tubular housing portion includes a circular edge that is bent radially inward around the edge of the closing element, particularly the edge of the metal disk. More preferably, the preceding features a. and b., and, where appropriate, a. to c., may also be used in combination.

[0075] In this advanced form, it is therefore preferable to fix the closing element within the further terminal opening by welding. In the case of a perimeter welded joint, a separate sealing element is not required.

[0076] The radial folding of the edges of the closing element is an optional measure not required for fixing the closing element, but it can nevertheless be appropriate.

[0077] In one evolutionary form, an energy storage battery in a further particularly preferred embodiment of the present invention has one of the following features a. to c.: a. The other end of the first longitudinal edge is directly adjacent to the metal disk and preferably joined to the metal disk by welding. b. The other end of the first longitudinal edge is welded to a contact sheet directly adjacent to the metal disk.

[0078] In principle, as with the contact element, it is also possible here that only an indirect connection exists between the other longitudinal edge of the first longitudinal edge and the metal disk or closing element via a contact sheet. In this case, preferably, there is a direct welded connection between the contact sheet and the closing element, particularly the metal disk. The contact sheet is preferably configured as its counterpart in the case of the contact element described above. Specifically, the side of the contact sheet facing the metal disk is in direct contact with the metal disk, thereby creating a two-dimensional contact surface, i.e., the contact sheet and the metal disk lie flat against each other in at least some area.

[0079] For the other coupling of the first longitudinal edge of the closing element to the metal disk or contact sheet, the same preferred embodiment, also applicable to the aforementioned coupling of the longitudinal edge to the base of the cup and the contact element, is applicable. To avoid repetition, the corresponding description is referred to in this regard (preferably a linear contact zone having a spiral progression, and maximum uniformity of coupling of the longitudinal edge to the metal disk along this linear contact zone by a preferred weld bond).

[0080] The metal disk of the closing element preferably has the same thickness as the metal disk of the contact element, specifically in the range of 50 μm to 600 μm, preferably in the range of 150 μm to 350 μm.

[0081] In particular, when the battery of the present invention is configured as a lithium-ion battery, the selection of the material from which the metal disk of the closing element is fabricated depends on whether the anode current collector or the cathode current collector is connected to the closing element. In principle, the preferred material is the same as the material from which the current collector itself is fabricated. The materials described above are also useful for the metal disk of the contact element.

[0082] Modified housing with two electrical insulation covers In a further particularly preferred embodiment of the present invention, the energy storage battery has at least one of the following four further features a. to d.: a. The battery includes an annular seal made of an electrically insulating material that surrounds the circular edge of the closure element, particularly the edge of the metal disk. b. The metal disc is positioned within the tubular housing portion such that the annular seal extends along the periphery contact zone on the inner surface of the tubular housing portion. c. The annular seal is compressed within the contact zone as a result of the pressure applied to it by the edge of the metal disc and the inner surface of the tubular housing portion. d. The tubular housing portion includes a circular edge that is surrounded by a seal and is bent radially inward around the edge of the closing element that secures the closing element within a further terminal opening of the tubular housing segment. More preferably, the preceding three features a. to c., and, where appropriate, the preceding four features a. to d., may be combined.

[0083] In one developmental form, the energy storage battery preferably has one of the following features a. and b.: a. The other end of the first longitudinal edge is directly adjacent to the metal disk and is joined to the metal disk by welding. b. The other end of the first longitudinal edge is welded to a contact sheet directly adjacent to the metal disk.

[0084] In these embodiments as well, the tubular housing portion replaces the housing cup together with the closing element. Therefore, the housing here also consists of three housing portions: one tubular portion and two others (contact element and closing element) that act as covers to close the end opening of the tubular portion. However, the contact element and closing element here are electrically insulated from the tubular housing portion. The contact element and closing element form the terminals of the battery.

[0085] For the configuration of the closing element, refer to the above description of the contact element. All preferred embodiments applicable to the contact element are also applicable to the closing element. In particularly preferred embodiments, the closing element and the contact element are, where appropriate, implemented in a mirror-symmetric manner with respect to each other, except for the metallic material selected in each case, which is generally selected according to their respective polarities.

[0086] For the other coupling of the first longitudinal edge of the closing element to the metal disk or contact sheet, the same preferred embodiment, also applicable to the aforementioned coupling of the longitudinal edge to the base of the cup and the contact element, is applicable. To avoid repetition, in this regard, the corresponding description is again referred to (preferably a linear contact zone having a spiral progression, and maximum uniformity of coupling of the longitudinal edge to the metal disk along this linear contact zone by a preferred weld bond).

[0087] Preferred electrode configuration Within the free-edge strip, preferably, the metal of each current collector does not contain the respective electrode material. In a preferred embodiment, the metal of each current collector is not coated therein, so that it is available for electrical contact connections, for example, by welding.

[0088] In further embodiments, the metal of each current collector within the free edge strip may, alternatively, be coated with a support material that is more thermally stable than a current collector coated with a support material, at least in some areas, and is different from the electrode material disposed on each current collector.

[0089] What is meant here by "greater thermal stability" is that the supporting material remains in a solid state at the temperature at which the current collector's metal melts. Therefore, it must have a higher melting point than the metal, or otherwise, it must sublimate or decompose only at the temperature at which the metal has already melted.

[0090] In principle, the support material usable in connection with the present invention may be a metal or a metal alloy, provided that it has a higher melting point than the metal to which the surface coated with the support material is made. However, in many embodiments, the energy storage battery of the present invention preferably has at least one of the following further features a. to d.: a. The supporting material must be a non-metallic material. b. The supporting material must be an electrical insulating material. c. The nonmetallic material is a ceramic material, a glass-ceramic material, or glass. d. The ceramic material is aluminum oxide (Al2O3), titanium oxide (TiO2), titanium nitride (TiN), aluminum titanium nitride (TiAlN), silicon oxide, especially silicon dioxide (SiO2), or titanium carbonitride (TiCN). The support material according to the present invention more preferably conforms to the preceding feature b., and particularly preferably conforms to the preceding feature d.

[0091] The term "nonmetallic materials" particularly includes plastics, glass, and ceramic materials. In this regard, the term "electrical insulating materials" should be interpreted broadly. In principle, it includes any electrical insulating material, particularly the polymers mentioned above. In this regard, the term "ceramic materials" should be interpreted broadly. In particular, it is understood to mean carbides, nitrides, oxides, silicides, or mixtures or derivatives of these compounds. The term "glass-ceramic materials" particularly means materials containing crystalline particles incorporated within an amorphous glass phase. The term "glass" in principle means any inorganic glass that meets the criteria for thermal stability defined above and is chemically stable to any electrolyte present in the battery. More preferably, the anode current collector is made of copper or a copper alloy, while the cathode current collector is made of aluminum or an aluminum alloy, and the supporting material is aluminum oxide or titanium oxide.

[0092] It may be even more preferable that the free edge strips of the anode current collector and / or cathode current collector are covered with a strip of support material.

[0093] The main regions of the anode and cathode current collectors, particularly the strip-shaped main regions, preferably extend parallel to the respective edges or longitudinal edges of the current collectors. Preferably, the strip-shaped main regions extend over at least 90%, more preferably at least 95%, of the areas of the anode and cathode current collectors. In some preferred embodiments, the support material is applied in the form of strips or lines immediately alongside the main regions, which are preferably strip-shaped, but does not completely cover the exposed areas, thereby leaving the metal of each current collector exposed immediately along its longitudinal edge.

[0094] Other preferred configurations of energy storage batteries The energy storage battery of the present invention may be a button cell. The button cell is cylindrical and has a height smaller than its diameter. The height is preferably in the range of 4 mm to 15 mm. It is more preferable that the button cell has a diameter in the range of 5 mm to 25 mm. The button cell is suitable for supplying electrical energy to small electronic devices such as watches, hearing aids, and wireless headphones.

[0095] The nominal capacity of the button battery of the present invention in the form of a lithium-ion battery is generally up to 1500mAh. The nominal capacity is preferably in the range of 100mAh to 1000mAh, and more preferably in the range of 100 to 800mAh.

[0096] However, more preferably, the energy storage battery of the present invention is a cylindrical circular battery. Cylindrical circular batteries have a height greater than their diameter. They are particularly suitable for the first listed applications with high energy requirements, such as in the automotive sector, or for electric bicycles or power tools.

[0097] The height of an energy storage battery in the form of a circular battery is preferably in the range of 15 mm to 150 mm. The diameter of a cylindrical circular battery is preferably in the range of 10 mm to 60 mm. Within these ranges, for example, shape factors of 18 × 65 (diameter × height (in mm)) or 21 × 70 (diameter × height (in mm)) are particularly preferred. Cylindrical circular batteries having these shape factors are particularly suitable for supplying power to electric drive systems in automatic vehicles.

[0098] The nominal capacity of the cylindrical circular battery of the present invention in the form of a lithium-ion battery is preferably up to 90,000 mAh. When having a shape factor of 21 × 70, the battery in one embodiment as a lithium-ion battery preferably has a nominal capacity in the range of 1,500 mAh to 7,000 mAh, more preferably in the range of 3,000 to 5,500 mAh. When having a shape factor of 18 × 65, the battery in one embodiment as a lithium-ion battery preferably has a nominal capacity in the range of 1,000 mAh to 5,000 mAh, more preferably in the range of 2,000 to 4,000 mAh.

[0099] In the European Union, manufacturer information regarding the nominal capacity of secondary batteries is strictly regulated. For example, information regarding the nominal capacity of secondary nickel-cadmium batteries is based on measurements in accordance with standards IEC / EN 61951-1 and IEC / EN 60622, information regarding the nominal capacity of secondary nickel-metal hydride batteries is based on measurements in accordance with standard IEC / EN 61951-2, information regarding the nominal capacity of lithium secondary batteries is based on measurements in accordance with standard IEC / EN 61960, and information regarding the nominal capacity of lead-acid secondary batteries is based on measurements in accordance with standard IEC / EN 61056-1. All numerical values ​​for nominal capacity in this application are preferably similarly based on these standards.

[0100] In embodiments of the present invention where the battery is a cylindrical circular battery, the anode current collector, cathode current collector, and separator are preferably band-shaped and preferably have the following dimensions: - Length within the range of 0.5m to 25m - Width within the range of 30mm to 145mm In these cases, the free-edge strip extending along the first longitudinal edge and not covered with electrode material preferably has a width of 5000 μm or less.

[0101] In the case of a cylindrical circular battery having a shape factor of 18 × 65, the current collector is preferably, - A width of 56mm to 62mm, preferably 60mm, and - Length of 1.5m or less It has.

[0102] In the case of a cylindrical circular battery having a shape factor of 21 × 70, the current collector is preferably, - A width of 56mm to 68mm, preferably 65mm, and - Length of 2.5m or less It has.

[0103] Manufacturing method The present invention's method for manufacturing energy storage batteries always features the following steps: a. Providing an electrode-separator assembly having an array of anodes / separators / cathodes in the form of cylindrical windings having two end faces and an intermediate winding shell, wherein each electrode has a current collector covered with electrode material and having a first longitudinal edge, a second longitudinal edge and two end faces, and one of the longitudinal edges of one electrode protrudes from one of the end faces. In this step, the electrode-separator assembly is provided as described above. Refer to the above description. b. Providing a tubular housing portion having a circular terminal opening. For possible configurations of this portion, refer to the above description relating to the battery of the present invention. c. Providing a contact element having a circular rim that is at least partially metallic. In this regard, refer to the description of the contact element relating to the battery of the present invention. d. The step of applying an annular seal to the circular edge of the contact element. e. A step of welding the longitudinal edge protruding from the end face to the contact element or a metal component of the contact element. The metal component of the contact element is, in particular, the contact sheet described above. The welding can be achieved, for example, by laser. The longitudinal edge is preferably connected here to the contact sheet according to one of the three variations of contact described above. f. A step of pushing the electrode-separator assembly into the tubular housing portion through a circular opening, thereby the wound shell is adjacent to the inner surface of the tubular housing portion, and the annular seal applied to the edge of the contact element extends along the periphery contact zone on the inner surface of the tubular housing portion. g. A step of applying radial pressure to a tubular housing portion, thereby pressing its inner surface against the edge of a contact element and an annular seal disposed between them being subjected to pressure and compression. The detailed steps do not necessarily have to be performed in the specified sequence. For example, the sequences in steps d., e., and f. can be switched.

[0104] In a preferred embodiment, the method further comprises at least one of the immediately following steps and / or one of the immediately following features: a. The tubular housing portion includes, in the axial direction, an essentially cylindrical central section, an end section extending to the edge of a circular opening, and optionally an intermediate transitional region. b. The transition region between the cylindrical central section and the terminal section includes an enlarged portion of the inner diameter of the stepped tubular housing portion. c. The terminal section, starting from the enlarged portion of the stepped shape, has an inner diameter that increases in the direction of the circular opening edge. d. The contact element, on which an annular seal is applied to the edge of the contact element, has an outer diameter smaller than the inner diameter of the tubular housing portion in the terminal section and larger than the inner diameter of the tubular housing portion in the cylindrical central section. e. The electrode-separator assembly is inserted into the tubular housing portion to such an extent that the contact elements rest on the stepped enlargement. More preferably, in one embodiment, the preceding step and / or features a. and b. and d. and e. are combined with each other, and often the preceding step and / or features a. to e. are also combined with each other.

[0105] In addition, in preferred embodiments, the method of the present invention is characterized by at least one of the features a. and b. immediately following: a. After the electrode-separator assembly is inserted, the transition region is radially curved and the seal is compressed so that the outer diameter of the end section matches the outer diameter of the cylindrical central section. b. After the outer diameters of the end sections are matched, the opening edge of the end section is bent radially inward around the edge of the contact element surrounded by the seal. It is particularly preferable to combine the preceding steps a. and b.

[0106] In this embodiment, the radially indented transition region is an extended portion in the form of a step. This operation can result in the bead described above.

[0107] In addition, in preferred embodiments, the method of the present invention is characterized by at least one of the following three features a. to c.: a. The electrode-separator assembly is impregnated with an electrolyte, and the electrolyte is introduced through a contact element or an aperture intended for the purpose within another housing portion. b. After the electrolyte is introduced and impregnated, the aperture is closed, for example, by joining or welding. c. Closure is achieved using a pressure relief device.

[0108] Further features and advantages of the present invention will become apparent from the claims and the following description of preferred embodiments of the invention, in conjunction with the drawings. Each of these features may be implemented individually or in combination with each other. [Brief explanation of the drawing]

[0109] The following are shown in schematic form in the diagrams. [Figure 1] These are various embodiments (cross-sectional views) of the contact element of the energy storage battery of the present invention. [Figure 2] This is a partial diagram (cross-sectional view) of the energy storage battery of the present invention. [Figure 3] This is a preferred embodiment (cross-sectional view) of the energy storage battery of the present invention. [Figure 4] This is a further preferred embodiment (cross-sectional view) of the energy storage battery of the present invention. [Figure 5] This is a further preferred embodiment (cross-sectional view) of the contact element of the energy storage battery of the present invention. [Figure 6] This is a further preferred embodiment (cross-sectional view) of the contact element of the energy storage battery of the present invention. [Figure 7] This is a further preferred embodiment (cross-sectional view) of the contact element of the energy storage battery of the present invention. [Figure 8] This is a visualization (cross-sectional view) of one embodiment of housing closure in the method of the present invention. [Figure 9] This is a diagram (cross-sectional view) of the method of the present invention for manufacturing the battery of the present invention. [Figure 10] This is a diagram (top view) of the weld bond for connecting the longitudinal joint of the current collector to the contact sheet of the contact element. [Modes for carrying out the invention]

[0110] Figure 1 shows cross-sectional views of various embodiments of a contact element 110 suitable for closing the energy storage battery 100 of the present invention. Specifically: A. What is shown herein is the simplest embodiment of the contact element 110 according to the present invention, namely a flat metal disk having a rounded circular periphery that extends on only one plane. The metal disk may be made of, for example, aluminum. The edge of the metal disk extends radially outward. B The contact element 110 shown herein includes a metal disc 111 and a terminal cover 112. The metal disc 111 and the terminal cover 112 each have a circular periphery and the same diameter. The metal disc 111 extends on only one plane, while the terminal cover 112 has a central recess. The two parts 111 and 112 of the contact element 110 are preferably joined to each other by welding (not shown). The two layers of the contact element 110 extend radially outward. C The contact element 110 shown here includes a metal disc 111 and a terminal cover 112. The terminal cover 112 is similar to the terminal cover in B. However, the edge 111a of the metal disc 111 is bent radially inward here, so that the metal disc 111 has a U-shaped cross-section in the edge region. The bent edge 111a surrounds the edge 112a of the terminal cover 112, thus fixing the terminal cover 112 on the metal disc 111. In addition, it is preferable that the metal disc 111 and the terminal cover 112 are welded to each other. D The contact element 110 shown herein includes a metal disc 111 and a contact sheet 113. The contact sheet 113 lies flat on the metal disc 111 and is preferably welded to it. The metal disc 111 may be made of, for example, stainless steel, and the contact sheet 113 may be made of, for example, an aluminum alloy. The edges of the contact element 110 flare outward in a radial direction. E The contact element 110 shown herein comprises only a metal disk. Compared to the metal disk shown in A, it is shaped to have a circular recess 111b on its upper surface and a corresponding ridge on its lower surface. The edges of the contact element 110 flares outward in a radial direction. F The contact element 110 shown here comprises only a metal disk. Compared to the metal disk shown in A, this has a radially folded edge 111a and, as a result, a two-layered edge region. The two-layered edge region has a U-shaped cross-section. G The contact element 110 shown herein includes a metal disc 111 and a terminal cover 112 having a central recess. The edge 111a of the metal disc 111 is here bent radially inward, so that the metal disc 111 has a U-shaped cross section in the edge region. The bent edge 111a surrounds the edge 112a of the terminal cover 112, thus securing the terminal cover 112 on the metal disc 111. The edges 111a and 112a of the metal disc 111 and the terminal cover 112 are preferably additionally joined to each other by circumferential welding (not shown). At the center of the metal disc 111 is a hole 114 that provides access to a cavity 116, which is sealed by the metal disc 111 and the terminal cover 112. Integrated within the terminal cover 112 is a pressure relief device 120 that can be triggered if excessive pressure occurs in the cavity 116. In its simplest form, the pressure relief device 120 could be a point of intentional destruction.

[0111] The energy storage battery 100 shown in Figure 2 features a contact element 110 shown in Figure 1B. The edge 110a of the contact element 110 is formed by the edges 111a and 112a of the metal disk 111 and the terminal cover 112, and the contact element 110 is surrounded by an annular seal 103 made of electrically insulating plastic. The contact element 110 together with the hollow cylindrical housing portion 101 forms the housing of the energy storage battery 100 and closes one of its end openings. The edge 101a of the housing portion 101 is surrounded by the seal 103 and is bent radially inward around the edge 110a of the contact element 100, which secures the contact element 110 within the circular opening of the tubular housing portion 101. Inside the housing, a spirally wound electrode-separator assembly 104 is axially aligned such that its wound shell 104a is adjacent to the inner surface of the tubular housing portion 101. The longitudinal edge 115a of the anode current collector protrudes from the upper end surface 104b of the wound electrode-separator assembly 104. This is welded directly onto the lower surface of the metal disk 111, for example, via a multi-pin bond.

[0112] The energy storage battery 100 shown in Figure 3 is an example of a modification of the housing described above, having a housing cup. Here again, the housing portion 101, which is hollow cylindrical, is a portion of the housing cup 107 that includes a circular base 107a. The housing cup 107 contains an interior in which an electrode-separator assembly 104 in the form of a wound body is axially aligned, along with a contact element 110, which is a flat metal disc having a central hole 114. After the electrolyte is introduced into the housing, the hole 114 is closed by a sheet metal disc 141. Naturally, it could also be introduced into the base 107a of the housing. The housing portion 101, and therefore the housing cup 101, is electrically isolated from the contact element 110 by a seal 103. The edge 101a of the housing portion 101 is surrounded by the seal 103 and is bent radially inward around the edge of the contact element 110, which secures the contact element 110 within the circular opening of the tubular housing portion 101. The tubular housing portion 101 includes, in the axial direction, a central section 130 adjacent to the inner surface 101b of the wound shell 104a and a contact section 135 adjacent to the inner surface 101b of the annular seal 103. The annular seal 103 is compressed within the contact section 135 as a result of the pressure applied to it by the edge of the contact element 110 and the inner surface 101b of the tubular housing portion 101.

[0113] The two sections 130 and 135 are separated from each other by a surrounding bead 133. In particular, where the longitudinal edge 115a of the anode current collector protrudes from the end face 104b of the winding, the bead 133 is not very prominent, and the inward protrusion on the inner surface 101b of the housing portion 101 is less than the thickness of one housing wall. The aforementioned winding is welded directly onto the inner surface of the contact element 110. At the bottom, the longitudinal edge 125a of the cathode current collector, which is welded directly onto the inner surface of the base 107a, emerges from the bottom end face 104c of the electrode-separator assembly 104 in the form of a winding. The use of space within the housing in this embodiment approaches theoretical optimality.

[0114] The energy storage battery 100 shown in Figure 4 is largely identical in design to the battery shown in Figure 3, except that the contact element 110 here includes a contact sheet 113 to which the longitudinal edge 115a of the anode current collector is welded. It additionally includes a terminal cover 112.

[0115] The energy storage battery 100 shown in Figure 5 is, so to speak, largely identical in design to the battery shown in Figure 3. The exception here is formed by a closure at the base. Instead of a cup 107, a hollow cylindrical tube with two end openings instead of one is used as the housing portion 101. The upper opening is closed as described in relation to Figure 3, while the lower opening is closed by a closure element 145. The closure element 145 used is a circular metal disc whose diameter approximately corresponds to the inner diameter of the hollow cylindrical tube. The edge 145a of the metal disc 145 is joined to the tubular housing portion via a periphery welded seam (not shown).

[0116] The energy storage battery 100 shown in Figure 6 differs from the battery in Figure 5 only in terms of the shape of the closure element 145. The latter has a 90° folded periphery that allows the edge region of the closure element to lie flat against the inner wall of the housing portion 101. This facilitates welding of the two portions.

[0117] The energy storage battery 100 shown in Figure 7 includes a hollow cylindrical housing portion 101, which is part of a housing cup 107 including a circular base 107a and a circular opening (defined by a rim 101a). The housing cup 107 is a deep-drawn portion. The housing cup 107 includes an interior 137 in which an electrode-separator assembly 104 in the form of a wound body is axially aligned, along with a contact element 110, which is a flat metal disc having a circular rim and a central hole 114 that closes the circular opening of the housing cup 107. The hole 114 served to introduce electrolyte into the housing and is closed by a sheet metal disc 141. A terminal cover 112 is welded over the latter. The sheet metal disc 141 has one or more elongated recesses that weaken its structure, so it can serve as a pressure relief valve.

[0118] The electrode-separator assembly 104 takes the form of a cylindrical winding, having two end faces, between which an outer winding shell adjacent to the inner surface of a hollow cylindrical housing portion 101 extends. It is formed from a positive electrode and a negative electrode, and separators 118 and 119, each being band-shaped and spirally wound.

[0119] The two end faces of the electrode-separator assembly 104 are formed by the longitudinal edges of the separators 118 and 119. The current collectors 115 and 125 protrude from these end faces. The corresponding extra lengths are identified as d1 and d2.

[0120] The anode current collector 115 protrudes from the upper end face of the electrode-separator assembly 104, and the cathode current collector 125 protrudes from the lower end face. The anode current collector 115 has a layer of negative electrode material 155 within its strip-shaped main region. The cathode current collector 125 has a layer of positive electrode material 123 within its strip-shaped main region. The anode current collector 115 has an edge strip 117 extending along its longitudinal edge 115a that does not have electrode material 155 on it. Instead, a coating 165 of ceramic-supported material is applied here to stabilize the current collector within this region. The cathode current collector 125 has an edge strip 121 extending along its longitudinal edge 125a that does not have electrode material 123 on it. Instead, a coating 165 of ceramic-supported material is applied here as well.

[0121] The edge 115a of the anode current collector 115 is in direct contact with the contact element 110 along its entire length and is connected to it by welding (particularly using a laser) in at least several sections, preferably along its entire length. Alternatively, the multi-pin bond described above may be present here. Thus, the contact element 112 simultaneously serves as both the electrical contact connection for the anode and the housing portion.

[0122] The edge 125a of the cathode current collector 125 is in direct contact with the base 107a along its entire length and is connected to it by welding (particularly using a laser) in at least several sections, preferably along its entire length. Alternatively, the multi-pin bond described above may also be present here. Thus, the base 107a not only serves as part of the housing but also plays a role in the electrical contact connection of the cathode.

[0123] Housing portions 101 and 110 are electrically insulated from each other by a seal 103. The edge 101a of housing portion 101 is surrounded by the seal 103 and is bent radially inward around the edge 110a of the contact element 100, which secures the contact element 110 within the circular opening 101c of the tubular housing portion 101. In the axial direction, the tubular housing portion 101 includes a section adjacent to the inner surface of the outer winding shell 104a and a contact section adjacent to the inner surface of the annular seal 103. The annular seal 103 is compressed within the contact section as a result of the pressure applied to it by the edge 110a of the contact element 110 and the inner surface of the tubular housing portion 101.

[0124] Immediately below the contact section, the housing portion 101 has a surrounding bead 133. The bead 133 is not very prominent, and its inward protrusion on the inner surface of the housing portion 101 is less than the thickness of one housing wall.

[0125] Closure of the end circular opening of the housing cup 107 by the contact element can be carried out according to Figure 8. Closure is achieved in several steps. Specifically: An electrode-separator assembly 104 in the form of a wound body is inserted into a hollow cylindrical housing portion 101, with an anode current collector 115 emerging from its end face. The edge 115a of the anode current collector 115 is in direct contact with a disk-shaped contact element 110 along its entire length, and is connected to it by welding (particularly using a laser) at least several sections, preferably along its entire length. This weld bond is formed before insertion of the electrode-separator assembly 104. An annular seal 103 is fitted onto the edge 110a of the contact element 110. The tubular housing portion 101 includes, in the axial direction, an essentially cylindrical central section 130, an end section 190 extending to a circular opening edge, and an intermediate transition region 180. The transition region 180 between the cylindrical central section 130 and the end section 190 includes a stepped enlargement 170 of the inner diameter of the tubular housing portion 101. The end section 190, starting from the stepped enlargement 170, has an inner diameter that increases in the direction of the circular opening edge 101a. The contact element 110, with the annular seal 130 applied to its edge 110a, has an outer diameter smaller than the inner diameter of the tubular housing portion 101 in the end section 190 and larger than the inner diameter of the tubular housing portion 101 in the cylindrical center section 130. The electrode-separator assembly 104 is inserted into the tubular housing portion 101 to the extent that the contact element 110 rests on the stepped enlargement 170. After the electrode-separator assembly 104 is inserted, the transition region 180 is radially curved and the seal 103 is compressed so that the outer diameter of the end section 190 matches the outer diameter of the cylindrical central section 130. The illustrated bead 133 is formed here. As can be clearly seen, it is directly below the contact element 110. It separates the housing portion 101 from the section adjacent to the seal 101 (contact), and the winding from the section 130 (central section) adjacent to the inner surface of the housing 101. After the outer diameters of the end section 190 are matched, the opening edge 101a of the end section 190 is bent radially inward around the edge 110a of the contact element 110, which is surrounded by the seal 103.

[0126] For the manufacture of the energy storage battery of the present invention, the process can be carried out according to Figure 9, and the individual process steps A to I are described below. First, an electrode-separator assembly 104 is provided, and a metal disc 102, which will serve as a contact plate 110, is placed on its upper end surface. In step B, this is welded to the longitudinal edge 125a of the cathode current collector. In step C, a perimeter seal 103 is fitted onto the edge of the contact plate 110. In step D, this is used to insert the electrode-separator assembly 104 into the housing cup 107 (which is manufactured as a deep-drawn portion, integrally formed, and includes not only a circular base but also a terminal circular opening 101c defined by a hollow cylindrical housing portion 101 and an edge 101a) until the longitudinal edge 115a of the anode current collector is in direct contact with the base of the housing cup 107. In step E, this is welded to the base of the housing cup 107. In step F, the opening edge 101a is folded radially inward. In step G, the housing is filled with electrolyte. The electrolyte is introduced into the housing through the opening 114. In steps H and I, the opening 114 is closed with the sheet metal portion 141, and the sheet metal portion 141 is welded onto the housing portion 110.

[0127] The embodiment shown in Figure 10 illustrates a modified contact connection for connecting the longitudinal edge of a current collector having a spiral structure to a contact sheet. Specifically: A. Here, the longitudinal edge of the current collector is directly adjacent to the contact sheet and is joined to the contact sheet via numerous spot weld bonds (called multi-pin bonds). B. Here, the longitudinal edge of the current collector directly adjacent to the contact sheet is fixed to the contact sheet via a number of sections connected to the contact sheet along its entire length by continuous welded joints.

Claims

1. An energy storage battery (100), having the following features: a. The battery includes an electrode-separator assembly (104) having an anode / separator / cathode arrangement. b. The electrode-separator assembly (104) takes the form of a cylindrical winding having two end faces (104b, 104c) and an intermediate winding shell (104a). c. The battery includes a housing that includes a metal tubular housing portion (101) having a circular end opening (101c), d. Within the housing, the electrode-separator assembly (104), which takes the form of a wound body, is aligned axially such that the wound body shell (104a) is adjacent to the inner surface (101b) of the tubular housing portion (101). e. The anode is band-shaped and includes a band-shaped anode current collector (115) having a first longitudinal edge (115a), a second longitudinal edge, and two end portions. f. The anode current collector (115) includes a strip-shaped main region on which a layer of negative electrode material (155) is placed, and a free edge strip (117) extending along the first longitudinal edge (115a) and on which the electrode material (155) is not placed. g. The cathode is band-shaped and includes a band-shaped cathode current collector (125) having a first longitudinal edge (125a), a second longitudinal edge, and two end portions. h. The cathode current collector (125) includes a strip-shaped main region on which a layer of positive electrode material (123) is placed, and a free edge strip (121) extending along the first longitudinal edge (125a) and on which the electrode material (123) is not placed. i. The anode and the cathode are arranged within the electrode-separator assembly (104) such that the first longitudinal edge (115a) of the anode current collector (115) protrudes from one of the end faces (104b, 104c), and the first longitudinal edge (125a) of the cathode current collector (125) protrudes from the other end face (104b, 104c). j. The battery includes at least a partially metallic contact element (110) that is in direct contact with and connected to one of the first longitudinal edges (115a, 125a). It has the following further distinctive features: k. The contact element (110) includes a circular edge portion (110a), l. The battery includes an annular seal (103) made of an electrically insulating material that surrounds the circular edge (110a) of the contact element (110), m. The contact element (110), together with the annular seal (103), closes the end circular opening (101c) of the tubular housing portion (101). It has, n. The tubular housing portion (101) includes, in the axial direction, a central section (130) adjacent to the inner surface (101b) of the wound shell (104a) and a contact section (135) adjacent to the inner surface (101b) of the annular seal (103), o. The central section (130) is separated from the contact section (135) by a recess (133) that circularly surrounds the outer surface of the tubular housing portion (101). p. The annular seal (103) is compressed within the contact section (135), q. The inner diameter of the contact section (135) of the tubular housing portion (101) is the same as the inner diameter of the central section (130) of the tubular housing portion (101), and r. The contact element (110) is a metal disk, and its edge corresponds to or forms the portion of the circular edge (110a) of the contact element (110), or includes such a metal disk. Energy storage battery (100).

2. Further features include: b. The contact element (110) is positioned within the tubular housing portion (101) such that the annular seal (103) extends along the peripheral contact zone on the inner surface (101b) of the tubular housing portion (101). c. The annular seal (103) is compressed within the contact zone as a result of the pressure applied to it by the edge (110a) of the contact element (110) and the inner surface (101b) of the tubular housing portion (101). d. One of the first longitudinal edges is directly adjacent to the contact element (110) and is joined to the contact element (110). The battery according to claim 1, having at least one of the following.

3. Further features include: b. The contact element (110) is positioned within the tubular housing portion (101) such that the annular seal (103) extends along the peripheral contact zone on the inner surface (101b) of the tubular housing portion (101). c. The annular seal (103) is compressed within the contact zone as a result of the pressure applied to it by the edge (110a) of the contact element (110) and the inner surface (101b) of the tubular housing portion (101). d. The contact element (110) includes a metal contact sheet (113) having two surfaces, one of which faces the direction of the metal disk (111) and is bonded to the metal disk (111). e. One of the first longitudinal edges (115a, 125a) is directly adjacent to and joined to the other surface of the contact sheet (113). The battery according to claim 1, having at least one of the following.

4. Further features include: a. Within the region of the surrounding recess (133), the outer diameter of the tubular housing portion (101) is reduced by 2 to 6 times or less the wall thickness of the housing within the region. The battery according to claim 2 or 3, having the following features.

5. Further features include: a. The tubular housing portion (101) is surrounded by the annular seal (103) and includes a circular edge portion (101a) that is bent radially inward around the edge portion (110a) of the contact element (110) which fixes the contact element (110) within the circular opening (101c) of the tubular housing portion (101). b. The contact section (135) extends axially on the recess (133) to the edge (101a) which is bent radially inward. The battery according to claim 4, having at least one of the following.

6. Further features include: a. The tubular housing portion (101) is the portion of the housing cup (107) that includes the circular base portion (107a). b. The other of the first longitudinal edge portions (115a, 125a) is directly adjacent to the base portion (107a) and is joined to the base portion (107a). A battery according to any one of claims 1 to 5, having at least one of the following:

7. Further features include: a. The tubular housing portion (101) has a further circular end opening. b. The battery (100) includes a closing element (145) having a circular edge (145a) that closes the further end opening, c. The closing element (145) for the further end opening is a metal disk, the edge of which corresponds to or forms the portion of the circular edge (145a) of the metal closing element (145), or includes such a metal disk. A battery according to any one of claims 1 to 5, having at least one of the following:

8. Further features include: a. The metal disk is positioned within the tubular housing portion such that its edge extends along the peripheral contact zone on the inner surface (101b) of the tubular housing portion (101). b. The edge of the metal disc is joined to the tubular housing portion (101) via a surrounding welded joint. c. The tubular housing portion (101) includes a circular edge portion (101a) that is bent radially inward around the edge portion (145a) of the closing element (145). The battery according to claim 7, having at least one of the following.

9. Further features include: a. The other of the first longitudinal edge portions (115a, 125a) is directly adjacent to the metal disk and is joined to the metal disk. b. The other end of the first longitudinal edge is welded to a contact sheet (113) directly adjacent to the metal disk. The battery according to claim 7 or 8, having one of the above.

10. Further features include: a. The battery includes an annular seal (103) made of an electrically insulating material that surrounds the circular edge of the closing element. b. The metal disc is positioned within the tubular housing portion such that the annular seal extends along the peripheral contact zone on the inner surface of the tubular housing portion. c. The annular seal is compressed within the contact zone as a result of the pressure applied to it by the edge of the metal disk and the inner surface of the tubular housing portion. d. The tubular housing portion is surrounded by the annular seal (103) and includes a circular edge that is bent radially inward around the edge of the closing element, which secures the metal closing element within the further terminal opening of the tubular housing segment. The battery according to claim 7, having at least one of the following.

11. Further features include: a. The other end of the first longitudinal edge is directly adjacent to the metal disk and is joined to the metal disk by welding. b. The other end of the first longitudinal edge is welded to a contact sheet directly adjacent to the metal disk. The battery according to claim 10, having one of the above.

12. The battery according to any one of claims 1 to 11, wherein the metal disk is arranged flat on one of the end faces (104b, 104c).

13. A method for manufacturing an energy storage battery (100) according to any one of claims 1 to 12, a. A step of providing an electrode-separator assembly (104) having an anode / separator / cathode array in the form of a cylindrical winding having two end faces (104b, 104c) and an intermediate winding shell (104a), wherein the electrode is covered with electrode material and each has a current collector (115, 125) having a first longitudinal edge (115a, 125a) and a second longitudinal edge and two end faces, and one of the longitudinal edges (115a, 125a) protrudes from one of the end faces (104b, 104c), b. A step of providing a tubular housing portion (101) having a circular end opening (101c), c. Providing a contact element (110) that is at least partially metal and has a circular edge (110a), d. The step of applying the annular seal (103) to the circular edge portion (110a) of the contact element (110), e. The step of welding the longitudinal edge portion protruding from the end face to the contact element (110) or a metal component of the contact element (110), f. A step of inserting the electrode-separator assembly (104) into the tubular housing portion (101) through the circular opening (101c), wherein the wound shell (104a) is adjacent to the inner surface (101b) of the tubular housing portion (101), and the annular seal (103) applied to the edge (110a) extends along the periphery contact zone on the inner surface (101b) of the tubular housing portion (101), g. A step of applying radial pressure to the tubular housing portion (101) such that its inner surface (101b) is pressed against the edge (110a) of the contact element (110), and the annular seal (103) disposed between them is subjected to pressure and compressed. Includes, h. The tubular housing portion (101) includes, in the axial direction, an essentially cylindrical central section (130), an end section (190) extending to a circular opening edge (101a), and an intermediate transition region (180), i. The transition region (180) between the cylindrical central section (130) and the terminal section (190) includes an enlarged portion (170) of the inner diameter of the stepped tubular housing portion (101), j. The contact element (110) to which the annular seal (130) is applied to the edge (110a) of the contact element (110) has an outer diameter smaller than the inner diameter of the tubular housing portion (101) in the end section (190) and larger than the inner diameter of the tubular housing portion (101) in the cylindrical central section (130), and k. The electrode-separator assembly (104) is inserted into the tubular housing portion (101) to such an extent that the contact element (110) rests on the stepped enlargement portion (170).

14. Further features and steps are as follows: a. The end section (190), which begins from the stepped enlarged portion (170), has an inner diameter that increases in the direction of the circular opening edge (101a). b. The electrode-separator assembly (104) is inserted into the tubular housing portion (101) to such an extent that the contact element (110) rests on the stepped enlarged portion (170). The method according to claim 13, characterized by at least one of the following.

15. Further features and steps are as follows: a. After the electrode-separator assembly (104) is inserted, the transition region (180) is curved radially and the annular seal (103) is compressed so that the outer diameter of the end section (190) matches the outer diameter of the cylindrical central section (130). b. After the outer diameters of the end section (190) are matched, the opening edge (101a) of the end section (190) is bent radially inward around the edge (110a) of the contact element (110) surrounded by the annular seal (103). The method according to claim 14, characterized by at least one of the following.

16. The following are further steps: a. The electrode-separator assembly (104) is impregnated with an electrolyte, and the electrolyte is introduced through the contact element (110) or an aperture (114) intended for a specific purpose within another housing portion. b. After the electrolyte is introduced, the aperture (114) is closed. c. The closure is achieved using a pressure relief device (120). The method according to any one of claims 13 to 15, characterized by at least one of the above.

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