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EP-3972037-B1 - ENERGY STORAGE CELL

EP3972037B1EP 3972037 B1EP3972037 B1EP 3972037B1EP-3972037-B1

Inventors

  • ENSLING, David
  • PYTLIK, EDWARD

Dates

Publication Date
20260513
Application Date
20200922

Claims (14)

  1. Energy storage cell (100) designed as a cylindrical round cell with an outer diameter of at least 30 mm, having the features a. The energy storage cell comprises an electrode-separator assembly (104) with the sequence anode / separator / cathode, b. the electrode-separator assembly (104) is in the form of a hollow cylindrical winding with two terminal end faces and a winding shell between them, c. The energy storage cell comprises a housing, d. the housing encloses a hollow cylindrical interior space, e. in the interior space of the housing, the electrode-separator assembly (104) formed as a winding is axially aligned, f. to delimit the interior space, the housing comprises - a first annular closure member (1010) having an outer diameter and an inner diameter, - a second annular closure member (1020) having an outer diameter and an inner diameter, - a first tubular housing part (1030) having two terminal circular openings, the diameter of the first tubular housing part (1030) being matched to the outer diameters of the first annular closure member (1010) and the second annular closure member (1020), - a second tubular housing part (1040) having two terminal circular openings, the diameter of the second tubular housing part (1040) being matched to the inner diameters of the first annular closure member (1010) and the second annular closure member (1020), g. the anode of the electrode-separator assembly is ribbon-shaped and comprises a ribbon-shaped anode current collector (115) having a first longitudinal edge (115a) and a second longitudinal edge, h. the anode current collector (115) comprises a strip-shaped main region loaded with a layer of negative electrode material (155) and a free edge strip (117) extending along the first longitudinal edge (115a) which is not loaded with the electrode material (155), i. the cathode of the electrode-separator assembly is ribbon-shaped and comprises a ribbon-shaped cathode current collector (125) having a first longitudinal edge (125a) and a second longitudinal edge, j. the cathode current collector (125) comprises a strip-shaped main region loaded with a layer of positive electrode material (123) and a free edge strip (121) extending along the first longitudinal edge (125a) which is not loaded with the electrode material (123), k. the anode and the cathode are formed and/or arranged within the electrode-separator assembly (104) relative to each other such that the first longitudinal edge (115a) of the anode current collector (115) protrudes from one of the terminal faces and the first longitudinal edge (125a) of the cathode current collector (125) protrudes from the other of the terminal faces; and l. the energy storage cell comprises an at least partially metallic contact element which is in direct contact with one of the first longitudinal edges (115a, 125a) and which is connected to this longitudinal edge by welding, as well as the additional features m. the first or the second annular closure member (1010, 1020) functions as the contact member, and n. the second tubular housing part (1040) defines a channel (1500) open at both ends and extending axially through the energy storage cell.
  2. The energy storage cell of claim 1, having the following additional feature: a. The channel (1500) open on both sides is set up for temperature control of the energy storage cell.
  3. The energy storage cell of claim 1 or claim 2, having the following additional feature: a. The channel (1500), which is open on both sides, is provided for the flow of a temperature control medium, in particular a gas or a liquid.
  4. An energy storage cell according to any one of the preceding claims, having the following additional feature: a. A metallic rod or tube is inserted into the channel (1500), which is open on both sides, as a tempering agent.
  5. An energy storage cell according to any one of the preceding claims, having the following additional feature: a. the cylindrical energy storage cell (100) has an outer diameter of at least 32 mm.
  6. An energy storage cell according to any one of the preceding claims, having the following additional feature: a. the energy storage cell (100) is a lithium-ion cell.
  7. A battery comprising at least two energy storage cells (100) according to any one of claims 1 to 6, and a device for tempering the energy storage cells via the channels (1500) of the energy storage cells that are open on both sides.
  8. The battery of claim 7, having the following additional feature: a. The battery energy storage cells (100) are arranged within battery modules (500) that are interconnected to form a battery.
  9. The battery of claim 7 or claim 8 having the following additional feature: a. The device for temperature control of the energy storage cells comprises means for introducing a temperature control medium into the channels (1500) of the energy storage cells, which are open on both sides.
  10. The battery of any one of claims 7 to 9, having at least one of the following additional features: a. The device for temperature control of the energy storage cells comprises means for driving a gaseous temperature control medium, in particular an air flow. b. The device for tempering the energy storage cell comprises means for directing a gaseous tempering medium, in particular an air flow, through the channels (1500) of the energy storage cells, which are open on both sides.
  11. The battery of any one of claims 7 to 9, having at least one of the following additional features: a. The device for tempering the energy storage cells comprises pumping means for moving a liquid temperature control medium. b. The device for tempering the energy storage cells comprises means for directing a liquid temperature control medium through the channels (1500) of the energy storage cells, which are open on both sides.
  12. A battery according to any one of claims 7 to 11, having the following additional features: a. Metal rods or tubes are inserted into the channels (1500) of the energy storage cells, which are open on both sides, as a temperature control agent. b. The metallic rods or tubes are coupled to cooling and/or heating means.
  13. A method of manufacturing an energy storage cell according to any one of claims 1 to 6 comprising the following steps: a. Providing an electrode-separator assembly (104) having at least the anode/separator/cathode sequence, said assembly being in the form of a hollow cylindrical winding having two terminal end faces and a winding shell therebetween, said electrodes each comprising a current collector (115, 125) having a first longitudinal edge (115a, 125a) and a second longitudinal edge, one of said longitudinal edges (115a, 125a) protruding from one of said terminal end faces and the other of said longitudinal edges protruding from the other of said terminal end faces, b. Providing the components of a housing, namely. - of a first annular closure member (1010) having an outer diameter and an inner diameter, - of a second annular closure member (1020) having an outer diameter and an inner diameter, - of a first tubular housing part (1030) having two terminal circular openings, the diameter of the first tubular housing part (1030) being matched to the outer diameter of the first annular closure member (1010) and the second annular closure member (1020), - of a second tubular housing part (1040) having two terminal circular openings, the diameter of the second tubular housing part (1040) being matched to the inner diameter of the first annular closure member (1010) and the second annular closure member (1020), c. Assembly of the housing under arrangement of the electrode-separator assembly (104) in the housing, d. Electrical contacting of the electrode-separator assembly with the annular closing elements of the housing by welding and e. Closing and/or sealing the housing.
  14. Method according to claim 13 comprising the following steps: a. The electrode-separator assembly being in the form of a hollow cylindrical winding is manufactured by winding the electrodes and the separator onto the second tubular housing part (1040).

Description

The present invention relates to an energy storage cell with an electrode-separator assembly in the form of a hollow cylindrical winding, a battery with several such energy storage cells, and a method for manufacturing such energy storage cells. SCOPE OF APPLICATION AND STATE OF THE ART Electrochemical cells are capable of converting stored chemical energy into electrical energy through a redox reaction. They typically comprise a positive and a negative electrode, separated by a separator. During discharge, electrons are released at the negative electrode through an oxidation process. This results in an electron current that can be drawn from an external electrical device, for which the electrochemical cell serves as an energy source. Simultaneously, an ion current corresponding to the electrode reaction occurs within the cell. This ion current passes through the separator and is facilitated by an ion-conducting electrolyte. If the discharge is reversible, meaning it's possible to reverse the conversion of chemical energy into electrical energy during discharge and thus recharge the cell, it's called a secondary cell. The common designation of the negative electrode as the anode and the positive electrode as the cathode for secondary cells refers to the discharge function of the electrochemical cell. Secondary lithium-ion cells are used in many applications today because they can provide high currents and are characterized by a comparatively high energy density. They are based on the use of lithium, which can migrate back and forth between the cell's electrodes in the form of ions. The negative and positive electrodes of a lithium-ion cell are typically formed by so-called composite electrodes, which include both electrochemically active and electrochemically inactive components. In principle, any material capable of absorbing and releasing lithium ions can be used as electrochemically active components (active materials) for secondary lithium-ion cells. Carbon-based particles, particularly graphitic carbon, are often used for the negative electrode. Other non-graphitic carbon materials capable of lithium intercalation can also be used. Furthermore... Metallic and semi-metallic materials that can be alloyed with lithium can also be used. For example, the elements tin, aluminum , antimony, and silicon are able to form intermetallic phases with lithium. Lithium cobalt oxide ( LiCoO₂ ), lithium manganese oxide ( LiMn₂O₄ ), lithium iron phosphate ( LiFePO₄ ), or derivatives thereof can be used as active materials for the positive electrode. The electrochemically active materials are usually contained in the electrodes in particle form. As electrochemically inactive components, composite electrodes generally comprise a planar and/or ribbon-shaped current collector, for example, a metallic foil, which serves as a support for the respective active material. The current collector for the negative electrode (anode current collector) can be made of copper or nickel, for example, and the current collector for the positive electrode (cathode current collector) of aluminum, for example. Furthermore, the electrodes can include, as electrochemically inactive components, an electrode binder (e.g., polyvinylidene fluoride (PVDF) or another polymer, such as carboxymethylcellulose), conductivity-enhancing additives, and other admixtures. The electrode binder ensures the mechanical stability of the electrodes and often also the adhesion of the active material to the current collectors. Lithium-ion cells typically use electrolytes consisting of solutions of lithium salts such as lithium hexafluorophosphate ( LiPF6 ) in organic solvents (e.g., ethers and esters of carbonic acid). In the production of a lithium-ion cell, the composite electrodes are combined with one or more separators to form a composite body. The electrodes and separators are usually bonded together under pressure, and sometimes also by lamination or bonding. The cell's basic functionality can then be achieved by impregnating the composite with the electrolyte. In many embodiments, the composite body is formed or processed into a coil. It typically comprises the sequence positive electrode / separator / negative electrode. Composite bodies are frequently manufactured as so-called bicells with the possible sequences negative electrode / separator / positive electrode / separator / negative electrode or positive electrode / separator / negative electrode / separator / positive electrode. For applications in the automotive sector, for e-bikes or for other applications with high energy demands such as in tools, lithium-ion cells with the highest possible energy density are needed, which are also able to withstand high currents during charging and discharging. Cells for the aforementioned applications are often designed as cylindrical cells, for example, with a form factor of 21 x 70 (diameter times height in mm). Cells of this type always comprise a composite body