GB2626585A

GB2626585A - A method for producing an electrode of a battery cell, a corresponding battery cell as well as a corresponding motor vehicle

Info

Publication number: GB2626585A
Application number: GB2301198.4A
Authority: GB
Inventors: Temeche Eleni
Original assignee: Mercedes Benz Group AG
Current assignee: Mercedes Benz Group AG
Priority date: 2023-01-27
Filing date: 2023-01-27
Publication date: 2024-07-31
Also published as: GB202301198D0

Abstract

A method for producing an electrode of a battery cell 14 involves use of an injection nozzle to inject a conductor and a cathode material 20, such as lithium nickel manganese cobalt oxide, into a porous electrolyte scaffold 18. The porous electrolyte scaffold may be provided through a freeze-tape casting 22. The porous electrolyte scaffold may be an oxide, sulfide or halide. After the injection process a heat treatment of the electrode may be performed. After the formation of the catholyte a dense solid electrolyte film may be deposited. A solid state battery may be constructed by combining the cathode 16 with dense solid electrolyte film (30, Figure 3), such as a dense LLZO-layer, and a lithium metal anode (32, Figure 3) A battery cell for a motor vehicle may be produced by this method.

Description

A METHOD FOR PRODUCING AN ELECTRODE OF A BATTERY CELL, A

CORRESPONDING BATTERY CELL AS WELL AS A CORRESPONDING MOTOR

VEHICLE

FIELD OF THE INVENTION

[0001] The present invention relates to the field of automobiles. More specifically, the present invention relates to a method for producing an electrode of a battery cell, in particular for a motor vehicle. Furthermore the invention relates to a corresponding battery cell as well as to a corresponding motor vehicle.

BACKGROUND INFORMATION

[0002] The problem with infiltrating a cathode into a porous solid-state electrolyte of a battery cell, in particular of an at least partially electrically operated motor vehicle, may be the adhesion between the cathode particles and the electrolyte particles. In addition, a typical infiltration process may require the use of solvents and binders to help with the adhesion. These commonly used solvents may not be chemically stable with sulfide-based electrolytes, resulting in poor electro-chemical performance. In addition, during a conventional infiltration process, the cathode loading may be significantly limited by the rate of infiltration, minimizing the energy density of the overall cell.

[0003] US 2019 326625 Al relates to semi-solid electrodes, which are pre-formed prior to inclusion in lithium ion batteries, lithium ion batteries which incorporate the semi-solid electrodes and methods of making the semi-solid electrodes. An electrochemical cell includes a semi-solid anode formed of anode active material injected with an electrolyte and a first electrolyte additive, the semi-solid anode having a first SEI layer; and a semisolid cathode formed of a cathode active material injected with an additional electrolyte and a second electrolyte additive, the semi-solid cathode having a second SEI layer, wherein the first electrolyte additive and the second solid electrolyte additive are different.

SUMMARY OF THE INVENTION

[0004] It is an object of the present invention to provide a method for producing an electrode of the cell, in particular of an at least partially electrically operated motor vehicle, a corresponding battery cell as well as to a corresponding motor vehicle, by which an energy density in the battery cell is increased.

[0005] This object is solved by a method, a corresponding battery cell as well as a corresponding motor vehicle according to the independent claims. Advantageous forms of configurations are presented in the dependent claims.

[0006] One aspect of the present invention relates to a method for producing an electrode of a battery cell, including the steps of providing a porous electrolyte scaffold and injecting a conductor and a cathode material into the porous electrolyte scaffold by an injection nozzle.

[0007] Therefore, a potential goal of 500 Wh/kg by increasing the cathode loading may be reached. Furthermore, the advantage of the present invention may be maximizing the overall energy density of the battery cell by increasing the cathode loading. In addition, dry powder injection process will reduce the cost of production compared to solvent-based infiltration systems. Most importantly, common solvents used for cathode electrode processing may not be environment-friendly, hence, the solvents are recovered, increasing production cost.

[0008] According to an embodiment, the porous electrolyte scaffold may be provided through a freeze-tape casting.

[0009] According to another embodiment, after the injection process, a heat treatment of the electrode of the battery cell may be performed.

[0010] In another embodiment, after the catholyte formation, a dense solid electrolyte thin film may be deposited.

[0011] In another embodiment, lithium as the cathode material may be injected into the porous electrolyte scaffold.

[0012] According to another embodiment, oxides, sulfides, or halides as the porous electrolyte scaffold may be provided.

[0013] Another aspect of the present invention relates to an electrode of a battery cell which is produced according to the method. Furthermore, the present invention relates to a battery cell with the electrode.

[0014] Another aspect of the present invention relates to an electrical energy storage device including at least one battery cell according to the preceding aspect. Furthermore, the present invention relates to a motor vehicle including the electrical energy storage device according to the preceding aspect, wherein the motor vehicle may be configured as an at least partially electrically operated motor vehicle or a fully electrically operated motor vehicle.

[0015] Further advantages, features, and details of the present invention derive from the following description of preferred embodiments as well as from the drawings. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and/or shown in the figures alone can be employed not only in the respectively indicated combination but also in any other combination or taken alone without leaving the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The novel features and characteristic of the disclosure are set forth in the appended claims. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and together with the description, serve to explain the disclosed principles. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system and/or methods in accordance with embodiments of the present subject matter are now described below, by way of example only, and with reference to the accompanying figures.

[0017] The drawings show in: [0018] Fig. 1 a schematic side view according to an embodiment of a motor vehicle; [0019] Fig. 2 a schematic perspective view according to an embodiment of the method; and [0020] Fig. 3 a schematic side view according to an embodiment of an electrode of a battery cell.

[0021] In the figures the same elements or elements having the same function are indicated by the same reference signs.

DETAILED DESCRIPTION

[0022] In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration". Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

[0023] While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will be described in detail below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.

[0024] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion so that a setup, device or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a system or apparatus preceded by "comprises" or "comprise" does not or do not, without more constraints, preclude the existence of other elements or additional elements in the system or method.

[0025] In the following detailed description of an embodiment of the disclosure, reference is made to the accompanying drawings that form part hereof, and in which is shown by way of illustration a specific embodiment in which the disclosure may be practiced. This embodiment is described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.

[0026] Fig. 1 shows a schematic side view according to an embodiment of a motor vehicle 10. The motor vehicle 10 is at least in part electrically operated or fully electrically operated. Therefore, the motor vehicle 10 includes at least one electrical energy storage device 12, wherein the electrical energy storage device 12 includes a plurality of battery cells 14. The battery cells 14 include, for example, an anode as well as a cathode 16 (Fig. 2) as an electrode.

[0027] Fig. 2 shows a schematic respective view according to an embodiment of the present invention. In particular, Fig. 2 shows a method for producing the electrode, in particular a cathode 16, of the battery cell 14. A porous electrolyte scaffold 18 is provided, and ion conductor and a cathode/catholyte material 20 may be injected into the porous electrolyte scaffold 18 by an injection nozzle. In particular, the porous electrolyte scaffold 18 may be provided through a freeze-tape casting 22. Furthermore, after the injection process, a heat treatment of the cathode/catholyte and electrolyte 16 may be performed For example, a porous sulfide electrolyte scaffold may be prepared via freeze tape casting method and a mixture of catholyte (i.e mixture of lithium nickel manganese cobalt oxide cathode and halide electrolyte) may be injected into the porous scaffold. The addition of electrolyte in the cathode mixture prior to injection is mainly to increase the ion conduction pathway. If the ion/electron conductivity of the cathode is sufficient, addition of electrolyte is not required. For example, a porous oxide electrolyte scaffold may be prepared by freeze tape casting method and a cathode (lithium nickel manganese oxide) may be injected into the porous electrolyte. Furthermore, after the catholyte formation, a dense solid electrolyte thin film 30 (Fig. 3) may be deposited. In another embodiment, as the porous electrolyte scaffold 18 oxides or sulfides or halides may be provided.

[0028] Fig. 2 shows further an ice front 24 during the freezing process as well as a so-called doctor blade 26.

[0029] Furthermore, Fig. 2 shows a block 28, wherein this block 28 is shown in an enlarged form in Fig. 3. Fig. 3 shows a schematic side view according to Fig. 2. In particular, Fig. 2 shows the cathode 16 that may be formed by injecting the cathode material 20 into the porous electrolyte scaffold 18 layered with the dense solid electrolyte thin film 30 and a lithium metal anode 32. In particular, it is shown that the porous electrolyte scaffold 18 is produced or characterized through a freeze-tape casting 22. The cathode 16 may include Lithium Nickel Manganese cobalt oxide (NMC), Lithium iron phosphate (LFP), Lithium manganese iron phosphate (LMFP), and Lithium Nickel Manganese oxide (LNMO). For example, the cathode 16 may be built by injecting a conductor and high energy density cathode materials 20 into the porous scaffolds. The injection method may produce better contact between the cathode 16, the porous electrolyte scaffold 18, and/or the dense solid electrolyte thin film 30. The solid-state batteries may be constructed by combining the cathodes 16 with the dense solid electrolyte thin film 30 such as a dense LLZO-layer (lithium-lanthanum-zirconium-oxide) and a lithium metal anode 32.

[0030] In particular, the figures show that the solution to maximize the cathode loading into a porous solid-state electrolyte may be to utilize a powder or ink injection method. In this process, high-energy dense cathode active material such as cathode material 20 may be fed through the ink injection nozzle to deposit the active materials into the porous electrolyte scaffold 18. Depending on the chemistry of the battery cell 14, post heat treatment may be required. The nozzle plate may be a significant component, as it may directly determine the cathode loading. Hence, electro-formed nozzle plate with ultra-high precision and superior chemical and mechanical stability may be ideal for this application. After the cathode formation, a dense solid electrolyte thin film, in particular thinner than 25 mm, may be deposited. In some embodiments, this configuration could enable an anode-free cell configuration so the present invention is not limited to the utilization of lithium metal, silicon, or graphite anodes.

[0031] The nozzles may be optimized to feed different particle sizes cathode active materials Lithium Nickel Manganese cobalt oxide (NMC), Lithium iron phosphate (LFP), Lithium manganese iron phosphate (LMFP), and Lithium Nickel Manganese oxide (LNMO) into the porous electrolyte scaffold 18. Electrolytes that may be used for this application are not limited to, but may include oxides, preferably using ink injection, sulfides, preferably using dry powder injection, and/or halides.

Reference Signs motor vehicle 12 electrical energy storage device 14 battery cell 16 cathode 18 porous electrolyte scaffold cathode material 22 freeze-tape casting 24 ice front 26 doctor blade 28 box dense solid electrolyte 32 lithium metal anode

Claims

SCLAIMS1. A method for producing an electrode of a battery cell (14), comprising the steps of: - providing a porous electrolyte scaffold (18); and - injecting a conductor and a cathode material (20) into the porous electrolyte scaffold (18) by an injection nozzle.
2. The method according to claim 1, characterized in that the porous electrolyte scaffold (18) is provided through a freeze-tape casting (22).
3. The method according to claim 1 or 2, characterized in that after the injection process a heat treatment of the electrode of the battery cell (14) is performed.
4. The method according to any one of claims 1 to 3, characterized in that after the catholyte formation, a dense solid electrolyte thin film is deposited.
5. The method according to any one of claims 1 to 4, characterized in that Lithium nickel manganese cobalt oxide as the cathode material (20) is injected into the porous electrolyte scaffold (18).
6. The method according to any one of claims 1 to 5, characterized in that as the porous electrolyte scaffold (18) oxides or sulfides or halides are provided.
7. A battery cell (14) for a motor vehicle (10), wherein the battery cell (14) is produced with a method according to any of claims 1 to 6.
8. A motor vehicle (10) comprising at least a battery cell (14) according to claim 7.