BIPOLAR SOLID BATTERY PACK WITH BIFUNCTIONAL CAPACITOR CONSTRUCTIONS AND METHOD FOR PRODUCE A BATTERY CATHOD OR ANODE WITH A CAPACITOR WALL

Abstract

A bipolar solid-state battery cell comprises a plurality of battery cells, each cell comprising a separator, an anode arranged on a first side of the separator, and a cathode arranged on a second side of the separator, the second side being opposite the first side. The anode is electrically connected to an anode current collector, and the cathode is electrically connected to a cathode current collector. A capacitor wall is arranged parallel to at least one outer surface of the anode or the cathode, the capacitor wall comprising a capacitor-active material.

Description

INTRODUCTION

[0001] The present invention relates to bifunctional capacitor electrode constructions for a gel-backed bipolar battery and, in particular, to a bipolar solid-state battery pack according to the preamble of claim 1, as is known essentially from US 2021 / 0021009 A1.

[0002] Further details of the state of the art can also be found in the publications DE 10 2014 220 953 A1 and DE 10 2015 210 806 A1.

[0003] Furthermore, the invention relates to a method for manufacturing a battery cathode or anode with a capacitor wall according to the preamble of claim 9.

[0004] Polymer blockers are used in gel-backed bipolar solid-state batteries to prevent potential leakage of gel electrolytes, especially at high temperatures. The polymer blocker is a passive component of these solid-state batteries and, as such, occupies valuable space within the battery without performing any active function.

[0005] Fig. Figure 1 is a representation of a bipolar solid-state battery cell 100, comprising a plurality of individual cells 101A, 101B, 101C, 101D, ..., 100n-1, and so on. Each cell of the plurality of individual cells 101A, 101B, 101C, 101D, ..., 100n-1, and so on, comprises anodes 104A, 104B, 104C, 104D, ..., 104n-1, cathodes 108A, 108B, 108C, 108D, ..., 108n-1, and solid-state electrolyte 106A, 106B, 106C, 106D, ..., 106n-1. Each individual cell has an anode current collector and a cathode current collector 102A, 102B, 102C, 102D, 102E, ..., 102n, which detect the current generated in each individual cell. The solid electrolyte 106A, 106B, 106C, 106D, ..., 106n-1 is a gelled electrolyte. Each cell of the plurality of individual cells 101A, 101B, 101C, 101D, ..., 101n-1, etc., has a blocker 202 and 204 that prevents the gel from leaking out of the individual cell. The blocker 202 and 204 comprises a polymer and prevents the gel electrolyte from leaking out of the individual cells.

[0006] As mentioned above, the polymer blockers 202 and 204 are passive components. While they take up space, they do not perform any positive energy-generating function and thus reduce the cell's energy generation capacity. It is therefore desirable to replace the polymer blocker with a component that generates energy and improves the battery cell's capacity. SUMMARY

[0007] According to the invention, a bipolar solid-state battery cell is presented. The bipolar solid-state battery cell comprises a plurality of battery cells, each cell having a separator, an anode arranged on a first side of the separator, and a cathode arranged on a second side of the separator, the second side being opposite the first side. The anode is in electrical connection with an anode current collector, and the cathode is in electrical connection with a cathode current collector. A capacitor wall is arranged parallel to at least one outer surface of the anode or the cathode, the capacitor wall comprising a capacitor-active material. According to the invention, the capacitor wall is separated from the at least one outer surface of the anode or the cathode by an air gap.

[0008] In another embodiment, the air gap is up to 0.1 millimeters thick.

[0009] In yet another embodiment, the capacitor wall has a wall thickness of 3 to 100 millimeters.

[0010] In yet another embodiment, the capacitor wall touches an outer surface of the anode or the cathode.

[0011] In yet another embodiment, the capacitor wall touches an outer surface of the anode or the cathode, which is adjacent to a current collector.

[0012] In yet another embodiment, the capacitor wall touches every surface of the anode or the cathode except for a surface that touches the separator.

[0013] In yet another embodiment, the capacitor wall is arranged parallel to at least two outer surfaces of the anode or the cathode, with the air gap arranged between each of the two outer surfaces of the anode or the cathode and the capacitor wall.

[0014] In yet another embodiment, the capacitor walls are arranged symmetrically around the separator.

[0015] In yet another embodiment, the capacitor walls are arranged asymmetrically around the separator.

[0016] In yet another embodiment, the capacitor wall further comprises an electrically conductive additive, a polymeric binder and a solid electrolyte.

[0017] Furthermore, according to the invention, a method for producing a battery cathode or anode with a capacitor wall is presented, characterized by the features of claim 9.

[0018] In one embodiment, the capacitor wall further comprises a conductive additive, a polymeric binder and a solid electrolyte.

[0019] In yet another embodiment, the active capacitor material is present in an amount of 50 to 99 wt.%, the conductive additive in an amount of up to 30 wt.%, the polymeric binder in an amount of up to 20 wt.% and the solid electrolyte in an amount of up to 30 wt.%, based on the total weight of the capacitor wall.

[0020] In yet another embodiment, the manufacturing process comprises unwinding the separator from a first roll and winding it onto a second roll. The sludge is disposed of between the unwinding and winding processes.

[0021] In yet another embodiment, the slurry is applied to the separator film continuously.

[0022] The above-mentioned features and advantages, as well as other features and advantages of the disclosure, are readily apparent from the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Further features, advantages and details are included only as examples in the following detailed description, which refers to the drawings in which: Fig. 1 a schematic representation of a prior art battery cell comprising polymer blockers to prevent electrolyte leakage; Fig. 2A - 2C Top views of various exemplary embodiments of the bipolar solid-state battery cell are; Fig. 2D is a top view of a non-inventive embodiment of a bipolar solid-state battery cell; Fig. 3A is a side view of the features of the cathode in a single cell of the bipolar solid-state battery cell; Fig. 3B is a side view of the features of the anode in a single cell of the bipolar solid-state battery cell; Fig. 4A is a schematic representation of the formation of a capacitor wall during a continuous process; and Fig. Figure 4B is a top view of the bipolar electrode before and after the formation of the capacitor wall during a continuous process. DETAILED DESCRIPTION

[0024] The following description is merely an example. It is understood that identical or corresponding parts and features are identified by appropriate reference numerals in the drawings.

[0025] This document discloses bifunctional bipolar electrodes used in a gel-based solid-state bipolar battery. In this battery, a capacitor material is used for the bifunctional bipolar electrode. Due to its excellent responsiveness and high electrolyte adsorption capacity, it acts both as a performance-enhancing element and as a "sealing blocker" at the electrode edges. The capacitor material facilitates current pickup from the anode and cathode and can improve current transfer to and from the current collector. The capacitor material and the capacitor walls formed from it are electrically conductive. It can also absorb the solid-state gel electrolyte, especially at high temperatures, thus preventing leakage if the stabilized gel electrolyte structure breaks down or begins to flow.This design eliminates the need for passive polymer blockers, which, as described above, merely take up space in the solid-state battery to prevent leakage.

[0026] The capacitor material is used as a wall (hereinafter referred to as the "capacitor wall") to surround the electrodes in the battery cells in a variety of configurations, which are explained in more detail in the following figures.

[0027] Fig. 2A - 2D are sectional views from above, illustrating exemplary embodiments in which the capacitor wall surrounds the electrode materials. While Fig. 2A - 2D, described as top-down sectional views, could also be side views of the battery cells. In other words, those described in Fig. The battery shown in Figure 2A - 2D could be rotated on its side, and the cross-sectional view would be essentially the same. In some embodiments, the capacitor wall does not directly contact the electrode materials (the anode or the cathode) and is separated from a side surface of these electrode materials by an air gap. In this arrangement, the capacitor wall lies only parallel to the side surface of the electrode materials and is separated from the side surface by the air gap. It does not contact the electrode materials at any point on its surface.

[0028] In some other embodiments, the capacitor wall does not directly contact the electrode materials (the anode or the cathode) and is separated from one side surface of these electrode materials by an air gap, but does contact the electrode materials along its base surface. In other embodiments, the capacitor wall directly contacts the electrode material (the anode or the cathode) at its side surfaces as well as along its base surfaces.

[0029] In one embodiment, each individual cell of the bipolar solid-state battery cell has a capacitor wall arranged parallel to at least one outer surface of an anode or a cathode and separated from that outer surface by an air gap. In another embodiment, each individual cell of the bipolar solid-state battery cell has at least two capacitor walls, each arranged parallel to at least one outer surface of an anode or a cathode and separated from that outer surface by an air gap.

[0030] In yet another embodiment, there are at least two capacitor walls, each arranged parallel to an outer surface of the anode in each individual cell, and at least two capacitor walls, each arranged parallel to an outer surface of the cathode in each cell. The at least two capacitor walls can each be in contact with an outer surface of the anode or separated from an outer surface of the anode by an air gap. The at least two capacitor walls can each be in contact with an outer surface of the cathode or separated from an outer surface of the cathode by an air gap.

[0031] In yet another embodiment, a capacitor wall is provided that contacts at least every outer surface of the anode or the cathode, except for the surface of the anode or the cathode that contacts the separator. In one embodiment, the capacitor walls can be distributed symmetrically around the separator. In another embodiment, the capacitor walls can be distributed asymmetrically around the separator.

[0032] Fig. Figure 2A shows a top view of an exemplary bipolar solid-state battery cell 300, comprising a plurality of individual cells 301A, 301B, 301C, 301C, ..., 300n-1, and so on. Each cell of the plurality of individual cells 301A, 301B, 301C, ..., 301n-1, and so on, comprises anodes 303A, 303B, 303C, ..., 303n, cathodes 305A, 305B, 305C, 305D, ..., 305n-1, and separators 304A, 304B, 304C, ..., 304n-1. Each individual cell has an associated current collector 302A, 302B, 302C, 302D, ..., 302n, which captures the current generated in that individual cell. Each current collector comprises an anode current collector and a cathode current collector. For example, current collector 302A (which contacts anode 303A) comprises an anode current collector 302A2 and a cathode current collector 302A1. Current collectors 302B, 302C, 302D, ..., 302n similarly each have an anode current collector and a cathode current collector.The anode current collector and the cathode current collector are usually in contact with each other. In one embodiment, the anode current collector and the cathode current collector are directly connected. In another embodiment, the anode current collector and the cathode current collector form a single unit during the manufacture of the current collector. A single unit with a cathode and an anode current collector is called a plated current collector. In some embodiments, the anode current collector and the cathode current collector are connected to each other via a thin (e.g., less than 5 micrometers thick) electrically conductive layer that comprises a different material than the anode current collector and the cathode current collector.

[0033] The separators 304A, 304B, 304C, 304D, ..., 304n-1 prevent contact between the anode and cathode materials. Each cell of the plurality of cells 301A, 301B, 301C, ..., 301n-1, etc., has capacitor walls 306 and 308 arranged on opposite sides, preventing the gel from leaking out of the individual cell. The capacitor walls 306 and 308 are made of a capacitor material composition that will be described in detail later.

[0034] Fig. Figures 2A-2D are sectional views from above, showing different arrangements of the capacitor walls 306 and 308 in cell 301A, and the details of these different arrangements are explained using only a single cell 301A (in each figure) for reference. In each of the Fig. The remaining individual cells 301B, 301C, etc., from 2A to 2D each have the same structure as the individual cell 301A, so a detailed description of their respective structures is omitted for the sake of brevity. Reference is made to the structures in the remaining individual cells 301B, 301C, etc., only if there is a significant difference that requires explanation.

[0035] With the following renewed reference to Fig. In cell 301A, the individual cell comprises two groups of capacitor walls 306 and 308, arranged on opposite sides parallel to the side faces of the anode 303A and the cathode 305A. Capacitor wall 306 is divided into two parts 306A and 306B, separated by the separator 304A, while capacitor wall 308, arranged along the opposite side face (of the anode 303A and the cathode 305A), is also divided into two parts 308A and 308B, separated by the separator 304A. Air gaps 310 and 312 separate the capacitor walls 306 and 308 from the side faces of the anode 303A and the cathode 305A, respectively. The air gaps 310 and 312 are described with reference to Fig. 3A and Fig. 3B is described in further detail. Fig. 3A and Fig. 3B are isolated sectional views from above along sections MM' and NN' in Fig. 2A.

[0036] Fig. Figure 3A shows a side view of the cathode 305A along section MM'. The cathode 305A is separated from the capacitor walls 306B, 306B1, 308B, and 308B1 by air gaps 310, 311, 312, and 313. The cathode 305A directly contacts the cathode current collector 302B1 and is electrically connected to it. The cathode current collector 302B1 is electrically connected to a cathode tongue 402, which is located outside the cell 301A. The cathode tongues of each cell in the battery can be connected to a common terminal (not shown). The cathode 305A is thus surrounded on all sides by the capacitor walls 306B, 306B1, 308B, and 308B1, but does not directly contact the capacitor walls. It should be noted that the capacitor walls 306B1 and 308B1 and the air gaps 311 and 313 are only visible in the sectional view of Fig. 3A can be seen (since it is a complete cross-sectional side view of the individual cell 301A, while Fig. 2A only shows a sectional view from above). A circular section LL' shows an extended view of the air gaps 310 and 311 between the cathode 305A and the capacitor walls 306B and 306B1.

[0037] Out of Fig. Figure 3A shows that the cathode 305A has circumferential dimensions D1 and D2 (i.e., the sides of the cathode 305A have lengths D1 and D2). In one embodiment, D1 can be equal to D2, in which case the cross-sectional area of ​​the cathode 305A is square. In another embodiment, D1 is not equal to D2; in this case, the cross-sectional area of ​​the cathode 305A is rectangular. D1 and D2 are independent of each other. It is desirable that D1 and D2 be between 50 and 500 millimeters in size. The air gaps 310 and 311, with thicknesses d1 and d2, can have a thickness of up to 0.1 millimeters, preferably from 0.01 to 0.1 millimeters. The thicknesses d1 and d2 are independent of each other and can be equal or different.

[0038] The opposing capacitor walls 306B and 308B each have a thickness represented by D3, while the opposing capacitor walls 306B1 and 308B1 each have a thickness represented by D4. D3 and D4 can be the same or different from each other. It should be noted that the thicknesses D3 and D4 are independent of each other and have values ​​from 3 to 100 millimeters. In one embodiment, it is desirable that d1 and d2 are the same. In another embodiment, it is desirable that D3 and D4 are the same.

[0039] Fig. Figure 3B shows a side view of anode 303A along section NN'. Anode 303A is separated from capacitor walls 306A, 306A1, 308A, and 308A1 by air gaps in a similar manner to that described above with respect to the cathode. The size of the air gaps, the size of the sides of anode 303A, and the thickness of the capacitor walls are shown in Figure 3B. Fig. 3B, as seen, resemble those used for cathode 305A in Fig. The components described in section 3A are not discussed further here. The anode 303A contacts an anode current collector 302A2. The anode current collector 302A2 is electrically connected to an anode tongue 403. The anode tongue 403 of each cell of the battery can be connected to a terminal (not shown).

[0040] Fig. Figure 2B shows a top view of an exemplary bipolar solid-state battery cell 300, comprising a plurality of individual cells 301A, 301B, 301C, ..., 300n-1, etc., wherein the capacitor wall 312A1 is arranged between the anode 303A and the current collector pair 302A, and the capacitor wall 312A2 is arranged between the cathode 305A and the current collector pair 302B. In the Fig. In the arrangement shown in Figure 2B, the capacitor walls surround the anode and the cathode by a) being in direct contact with one side face of the anode and one side of the cathode; and b) being separated from another side face of the anode and the cathode by an air gap. The remaining arrangement of the bipolar solid-state battery cell 300 is the same as that shown in Figure 2B. Fig. 2A and will not be discussed further here.

[0041] With the following reference to Fig. 2B, the capacitor walls 312A1 and 312A2 directly touch the anode 303A and the cathode 305A along a surface perpendicular to the in Fig. The capacitor walls 306 and 308 shown in Figure 2A are separated from the anode 303A and cathode 305A by an air gap 310, while the capacitor walls 308A and 308B are separated from the anode 303A and cathode 305A by an air gap 312. The capacitor walls 312A1 and 312A2 are separated from the capacitor walls 306A, 306B, 308A, and 308B by air gaps 310 and 312.

[0042] Fig. Figure 2C shows a top view of an exemplary bipolar solid-state battery cell 300, comprising a plurality of cells 301A, 301B, 301C, ..., 300n-1, etc., wherein the capacitor wall 312A1 is arranged between the anode 303A and the current collector pair 302A, and the capacitor wall 312A2 is arranged between the cathode 305A and the current collector pair 302B. In this embodiment, the capacitor walls 312A1 and 312A2 are in direct contact with the capacitor walls 306A, 306B, 308A, and 308B. The capacitor wall 312A1 contacts the capacitor wall 306A at a first end 314A1 of the capacitor wall 312A1. It touches the capacitor wall 308A at a second end 314A2 of the capacitor wall 312A1, the second end 314A2 being opposite the first end 314A1. The capacitor wall 312A2 touches the capacitor wall 306B at a first end 316A1 of the capacitor wall 312A2.It touches the capacitor wall 308B at a second end 316A2 of the capacitor wall 312A2, with the second end 316A2 being opposite the first end 316A1. In the case of... Fig. In the arrangements shown in Figure 2C, the capacitor walls 306A and 306B are separated from the anode 303A and the cathode 305A by an air gap 310. The capacitor walls 308A and 308B are separated from the anode 303A and the cathode 305A by an air gap 312.

[0043] Fig. Figure 2D shows another top view of an exemplary bipolar solid-state battery cell 300, comprising a plurality of individual cells 301A, 301B, 301C, ..., 300n-1, etc., wherein the capacitor wall 312A1 is arranged between the anode 303A and the current collector pair 302A, and the capacitor wall 312A2 is arranged between the cathode 305A and the current collector pair 302B. In this embodiment, the capacitor wall 312A1 contacts the capacitor walls 306A and 308A at their ends, while the capacitor wall 312A2 contacts the capacitor walls 306B and 308B at their ends, as previously shown in Figure 2D. Fig. 2C described. In this embodiment, contrary to the invention, there is no air gap between the capacitor walls 306A and 306B and the anode 303A or between the capacitor walls 308A and 308B and the cathode 305A. The capacitor wall therefore partially surrounds the anode and the cathode and directly contacts the anode and the cathode on three sides each.

[0044] In one variant of the in Fig. 2B, Fig. 2C or Fig. In the embodiments described in Figure 2D, the capacitor walls 312A1 and 312A2 can be present only at the anode or the cathode, and not simultaneously at both the anode and the cathode, for each cell in the bipolar solid-state battery cell 300. In other words, the capacitor walls can be arranged symmetrically or asymmetrically around the separator. This embodiment is not shown here, but can be easily understood by a person skilled in the art. For example, cell 301A in the Fig. 2B, Fig. 2C and Fig. 2D have the capacitor wall 312A1, 306A, 306B, 308A and 308B, but not the capacitor wall 312A2, while cell 301B can have all the capacitor walls as described in the embodiments of Fig. 2B, Fig. 2C or Fig. are represented in 2D.

[0045] In another, asymmetrical embodiment, the capacitor walls on opposite sides of the separator can have different thicknesses. For example, all capacitor walls on one side of the separator can have a greater thickness than those on the other side. In yet another embodiment, the capacitor walls on opposite sides of the separator can have different compositions. For example, the capacitor walls on one side of the separator can have a first composition, while the walls on the other side can have a second composition, the second composition being different from the first.

[0046] The following sections describe the materials used in the different structures of the 300 series bipolar solid-state battery cells. Fig. 2A, Fig. 2B, Fig. 2C or Fig. The 2D images show the materials in relation to the 300-cell bipolar solid-state battery, which is used in Fig. 2A is shown and described in detail, but can also be used for the ones in Fig. 2B, Fig. 2C or Fig. 2D representation of battery cells applies.

[0047] With the following renewed reference to Fig. The anode current collector of capacitor 2A comprises copper (302A2), while the cathode current collector of capacitor 302A1 comprises aluminum. The capacitor walls of capacitors 306A, 306B, 308A, and 308B comprise a capacitor-active material, a conductive additive, a polymeric binder, and a solid electrolyte.

[0048] The active capacitor material used in the capacitor wall comprises carbon-containing materials (e.g., activated carbon, graphene, single-walled carbon nanotubes, multi-walled carbon nanotubes, or a combination thereof), metal oxides, e.g., MOx (where M is a metal and M = Co, Ni, Nb, or a combination thereof), metal sulfides (e.g., TiS₂, CuS, NiS, or a combination thereof), intrinsically conductive polymers (e.g., polyaniline, polyacetylene, polythiophene, polypyrrole, or a combination thereof), or a combination thereof. The active capacitor material is present in an amount of 50 to 99, preferably 55 to 95, and more preferably 60 to 90 wt%, based on the total weight of the capacitor wall. Some of the carbon-containing materials mentioned above are described in more detail below. They are also used as conductive additives in the capacitor wall.

[0049] The conductive additive used in the capacitor wall comprises an electrically conductive additive. The electrically conductive additive preferably comprises an electrically conductive carbon-containing material. Examples of electrically conductive carbon-containing materials are carbon nanotubes, carbon black, activated carbon, graphene, graphite, graphite oxide, carbon fibers, or similar materials, or a combination thereof.

[0050] Carbon nanotubes include single-walled carbon nanotubes (SWNT), double-walled carbon nanotubes (DWNT), multi-walled carbon nanotubes (MWNT), or a combination thereof, with diameters of 2 to 100 nanometers, preferably 10 to 50 nanometers. They have a length of 20 to 10,000 nanometers, preferably 200 to 5,000 nanometers. Stretch ratios of more than 10, preferably more than 50, and further preferably more than 100 are desirable.

[0051] For use in the electrode, carbon black with a large surface area is preferred. Carbon black (subtypes include acetylene black, sewer black, furnace black, lamp black, and thermal black) is a material produced by the incomplete combustion of coal and coal tar, vegetable matter, or petroleum products, including fuel oil, tar for catalytic fluidized bed cracking, and ethylene cracking, under limited air supply. Carbon black is a form of paracrystalline carbon with a high surface area to volume ratio, though lower than that of activated carbon. In the slurry used to manufacture the electrode, carbon black with a surface area of ​​50 to 1000 m² can be used. 2 / gm should be used.

[0052] Activated carbon, also known as activated coal, is a form of carbon with a surface area of ​​more than 3,000 m². 2 / gm, which is determined by gas adsorption. It may be used in conjunction with other electrically conductive carbon-containing elements listed here. Examples of carbon black or activated carbon that may be used in the electrode-forming slurry are Keltjen™ Black or Super P.

[0053] Graphene is an allotrope of carbon, consisting of a single layer of atoms arranged in a hexagonal lattice nanostructure. Graphene added to the slurry can be in the form of individual graphene sheets or as a multitude of loosely connected graphene sheets. Each atom in a graphene sheet is connected to its three nearest neighbors by σ-bonds and a delocalized π-bond, which contributes to a valence band that extends across the entire sheet. This is the same type of bonding found in carbon nanotubes and polycyclic aromatic hydrocarbons, as well as in fullerenes and glassy carbon. The valence band is touched by a conduction band, making graphene a semimetal with unusual electronic properties best described by theories of massless relativistic particles.

[0054] Graphite particles can also be used in the electrically conductive composition. Graphite is a natural form of pure carbon with a hexagonal crystal structure arranged in multiple parallel planes, known as graphene sheets. In short, graphite particles comprise a multitude of graphene sheets arranged parallel to one another. This anisotropic structure gives graphite special properties, such as electrical conductivity and exceptional strength along the individual layers. It is extremely heat-resistant, with a sublimation point exceeding 3,800 °C, highly thermally conductive, and chemically inert.

[0055] Graphite oxide (GO), sometimes called graphene oxide, graphitic oxide, or graphitic acid, is a compound of carbon, oxygen, and hydrogen in varying ratios, obtained by treating graphite with strong oxidizing agents and acids to dissolve additional metals. The maximally oxidized bulk material is a yellow solid with a C:O ratio between 2.1:1 and 2.9:1, retaining the layered structure of graphite, but with much larger and irregular intervals. The bulk material disperses spontaneously in basic solutions or can be dispersed by sonication in polar solvents to obtain monomolecular sheets, which, by analogy to graphene, the single-layer form of graphite, are called graphene oxide.Graphene oxide sheets are available in the form of strong paper-like materials, membranes, thin films and composite materials, and can be used in electrode-forming slurries for the manufacture of electrodes.

[0056] Carbon fibers have a diameter of 5 to 10 micrometers and consist mainly of carbon atoms. They can have a length of more than 1000 micrometers, preferably more than 10,000 micrometers. They are produced by drawing pitch or polyacrylonitrile polymer fibers under high pressure and at temperatures above 1500 °C, preferably at temperatures above 2200 °C. Carbon fibers differ from carbon nanotubes and do not have concentrically arranged cylindrical graphene sheets. The carbon fibers typically consist of high-aspect-ratio graphene sheets arranged parallel to each other.

[0057] The carbon nanotubes, carbon black, activated carbon, graphene sheets, graphite particles, graphite oxide particles, or a combination thereof mentioned above can be used individually or in any combination to form an electrically conductive network in the capacitor wall. In one exemplary embodiment, the carbon nanotubes are typically used in the largest quantity compared to the other carbon-containing components.

[0058] The capacitor walls 306A, 306B, 308A and 308B can comprise the electrically conductive additive in an amount of up to 30 wt.%, preferably less than 20 wt.% and further preferably less than 10 wt.%, based on the total weight of the capacitor wall. If the electrically conductive additive is present, the capacitor wall can, in one embodiment, comprise it in an amount of 1 wt.% or, more preferably, 2 wt.% or more.

[0059] The capacitor walls 306A, 306B, 308A, and 308B may include a binder that facilitates maintaining the capacitor wall in a monolithic form and prevents the materials used in the capacitor wall from dispersing during the manufacturing process. The binder is preferably a polymeric binder that facilitates the binding of particles of the active capacitor material, the electrically conductive additive, and the optional solid electrolyte. The polymeric binder facilitates the dimensional stability of the capacitor walls. The polymeric binder generally comprises an organic polymer.Examples of organic polymers include poly(tetrafluoroethylene) (PTFE), styrene-ethylene-butylene-styrene copolymer (SEBS), styrene-butadiene-styrene copolymer (SBS), acrylonitrile butadiene rubber (NBR), styrene-butadiene rubber (SBR), poly(propylene carbonate) PPC, sodium carboxymethyl cellulose (CMC), poly(vinylidene fluoride) (PVDF), poly(vinylidene fluoride-cohexafluoropropylene) (PVdF-HFP), polyacrylonitrile (PAN), poly(vinylidene fluoride-cochlorotrifluoroethylene) (P(VDF-CTFE)), poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TeFE)), poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer (P(VDF-TrFE-CFE)), or a combination thereof. In a preferred embodiment, the polymeric binder used in the active layer is a poly(vinylidene fluoride-hexafluoropropylene) copolymer. The polymeric binder has a weight-average molecular weight of 5,000 to 1,000,000 grams per mole, preferably 50,000 to 750,000 grams per mole, and more preferably 75,000 to 500,000 grams per mole.000 grams per mole, measured by gel permeation chromatography with a polystyrene standard.

[0060] The polymeric binder is present in an amount of up to 20 wt.%, preferably up to 10 wt.% and further preferably up to 1 wt.%, based on the total weight of the capacitor wall.

[0061] The capacitor walls 306A, 306B, 308A, and 308B may also include a solid electrolyte. The solid electrolyte may be a sulfide solid electrolyte, an oxide-based solid electrolyte, a metal-doped or aliovalently substituted oxide solid electrolyte, a nitride-based solid electrolyte, a halide-based solid electrolyte, a hydride-based solid electrolyte, or a combination thereof.

[0062] The solid electrolyte generally comprises a pseudobinary sulfide, a pseudoternary sulfide, a pseudoquaternary sulfide, or a combination thereof. Examples of pseudobinary sulfides include the Li₂S-P₂S₅ system (e.g., Li₃PS₄, Li₇P₃S₅). 11 and Li 9,6 P3S 12 ), the Li₂S-SnS₂ system (e.g., Li₄SnS₄), the Li₂S-SiS₂ system, the Li₂S-GeS₂ system, the Li₂S-B₂S₃ system, the Li₂S-Ga₂S₃ system, the Li₂S-P₂S₃ system, the Li₂S-Al₂S₃ system, or a combination thereof. Examples of pseudoternary sulfides are the Li₂O-Li₂S-P₂S₅ system, the Li₂S-P₂S₅-P₂O₅ system, the Li₂S-P₂S₅-GeS₂ system (e.g., Li₂S-Ga₂S₃ ... 3,25 Ge 0,25 P 0,75 S4 and Li 10 GeP2S 12 ), the Li2S-P2S5-LiX system (with X = F, Cl, Br or I, examples of which are Li6PS5Br, Li6PS5Cl, L7P2S8I and Li4PS4I), the Li2S-As2S5-SnS2 system (e.g., Li 3,833 Sn 0,833 As 0,166S4), the Li2S-P2S5-Al2S3 system, Li2S-LiX-SiS2 (with X = F, Cl, Br or I, which includes the examples 0.4LiI-0.6Li4SnS4 and Li 11 Si2PS 12 This includes sulfide-based solid electrolytes such as Li₂S-P₂S₅ systems and Li₂S-P₂S₅ MO systems. X -systems, Li2S-P2S5-MS x -systems, LGPS (Li 10 GeP2S 12 ), Thio-LISICONs (Li 3,25 Ge 0,25 P 0,75 S4), Li 3,4 Si 0,4 P 0,6 S4, Li 10 GeP2S 11,7 O 0,3 , lithium argyrodite (e.g. Li6PS5X (X = Cl, Br or I), Li 9,54 Si 1,74 P 1,44 S 11,7 Cl 0,3 ), Li 9,6 P3S 12 , Li7P3S 11 , Li9P3S9O3, Li 10,35 Ge 1,35 P 1,65 S 12 , Li 10,35 Si 1,35 P 1,65 S 12 , Li 9,81 Sn 0,81 P 2,19 S 12 , Li 10 (Si 0,5 Ge 0,5 )P2S 12 , Li 10 (Ge 0,5 Sn 0,5 )P2S 12, Li 10 (Si 0,5 Sn 0,5 )P2S 12 Li 3,833 Sn 0,833 As 0,166 S4),Lil-Li4SnS4, Li4SnS4, or a combination thereof.

[0063] Solid oxide-based electrolytes include garnets (e.g., Li7La3Zr2O). 12 ), perovskites (e.g. Li 3x La 2 / 3-x TiO3), NASICONs (e.g., Li 1,4 Al 0,4 Ti 1,6 (PO4)3 and Li 1+x Al x Ge 2-x (PO4)3), LISICONs (e.g. Li 2+2x Zn 1-x GeO4) or a combination thereof.

[0064] Metal-doped or aliovalently substituted oxide solid-state electrolytes can also be used in the capacitor walls. Examples include Al (or Nb)-doped Li7La3Zr2O. 12 , Sb-doped Li7La3Zr2O 12 , Ga-substituted Li7La3Zr2O 12 , Cr- and V-substituted LiSn2P3O 12 , Al-substituted perovskite, Li 1+x+y Al x Ti 2-x Si y P 3-y O 12or a combination thereof.

[0065] Solid-state electrolytes based on nitrides, such as Li3N, Li7PN4, LiSi2N3 or a combination thereof, can also be used in the capacitor wall.

[0066] Solid-state electrolytes based on hydrides such as LiBH4, LiBH4-LiX(X = Cl, Br or I), LiNH2, Li2NH, LiBH4-LiNH2, Li3AlH6 or a combination thereof may also be used in the capacitor wall.

[0067] Solid-state electrolytes based on halides, such as Li1, Li3InCl6, Li2CdCl4, Li2MgCl4, Li2CdI4, Li2Zn14, Li3OCl or a combination thereof, can also be used in the capacitor wall.

[0068] Solid-state electrolytes based on borates, such as Li₂B₄O₇, Li₂O-B₂O₃-P₂O₅, or a combination thereof, can also be used in the capacitor wall. The solid electrolyte can be used in the capacitor wall in an amount of up to 50 wt.%, preferably less than 30 wt.%, and more preferably less than 15 wt.%, based on the total weight of the cathode-active layer 108. In one embodiment, the solid electrolyte can be used in the active cathode layer in an amount of 1 wt.% or more, preferably 2 wt.% or more, based on the total weight of the cathode-active layer 108.

[0069] The cathode 305A (see Fig. 2A, Fig. 2B, Fig. 2C or Fig. 2D) comprises a cathode-active material, a conductive additive, a binder and a solid electrolyte.

[0070] The cathode-active material comprises lithium cobalt oxide (LCO, sometimes also called "lithium cobaltate" or "lithium cobaltite", a variant of which is LiCoO2); lithium nickel manganese cobalt oxide (NMC, with a different formula of Li-NiMnCo); lithium manganese oxide (LMO, with different formulas of LiMn2O4, Li2MnO3 and others); lithium nickel cobalt aluminum oxide (LiNiCoAlO2 and variants thereof as NCA); and lithium titanate oxide (LTO, with a variant formula of Li4Ti5O). 12 ); Lithium iron phosphate oxide (LFP, with a variant formula LiFePO4), lithium nickel cobalt aluminum oxide (and variants thereof as NCA) and other similar materials, spinel (LiMn2O4, LiNi 0,5 Mn 1,5O4), polyanion cathode (LiV2(PO4)3), and other lithium transition metal oxides. The surface-coated and / or doped cathode materials mentioned above, e.g., LiNbO3-coated LiMn2O4 and Al-doped LiMn2O4, may also be used. Low-voltage cathode materials, e.g., lithiated metal oxide / sulfide (e.g., LiTiS2), lithium sulfide, and sulfur, may also be used.

[0071] Other variations of the above may be included. In some embodiments where NMC is used as the active material, nickel-rich NMC may be employed. In some embodiments, the NMC variant may, for example, be LiNi. x Mn y Co (1-x-y) O2, LiNi x Mn y Al( 1-x-y )O2, LiNi x Mn (1-x) O2, Li 1+xMO2, where x is equal to or greater than approximately 0.7, 0.75, 0.80, 0.85 or more, and where y is less than 0.15, preferably less than 0.1. In some embodiments, NMC811 may be used, where in the above formula x is approximately 0.8 and y is approximately 0.1.

[0072] The active cathode material is present in the cathode in an amount of 30 to 95 wt.%, preferably 40 to 80 wt.% and more preferably 45 to 75 wt.%, based on the total weight of the cathode.

[0073] The cathode can comprise a conductive additive in amounts of up to 30 wt.%, preferably up to 20 wt.%, and preferably up to 10 wt.%, based on the total weight of the cathode. The conductive additive can also be present, if any, in amounts of 1 wt.% or more, preferably 2 wt.% or more, based on the total weight of the cathode. The conductive additives listed above can also be used in the cathode and are therefore not listed again for the sake of brevity.

[0074] The cathode may also comprise a polymeric binder in amounts of up to 20 wt.%, preferably up to 15 wt.%, and preferably up to 10 wt.%, based on the total weight of the cathode. The polymeric binder, if present, may also be present in amounts of 1 wt.% or more, preferably 2 wt.% or more, based on the total weight of the cathode. The cathode may also comprise a solid electrolyte in amounts of up to 30 wt.%, preferably up to 25 wt.%, and preferably up to 10 wt.%, based on the total weight of the cathode. The solid electrolyte, if present, may also be present in amounts of 1 wt.% or more, preferably 2 wt.% or more, based on the total weight of the cathode. Both the polymeric binder and the solid electrolyte used in the cathode may be the same as those listed above for the capacitor wall and are therefore not repeated here.

[0075] The anode 303A (see Fig. 2A, Fig. 2B, Fig. 2C or Fig. 2D) comprises an anode-active material, an electrically conductive additive, a binder and a solid electrolyte.

[0076] Active anode materials include some of the carbon-containing materials mentioned above, hard carbon, silicon, silicon mixed with graphite, silicon particles encapsulated in carbon, and Li4Ti5O. 12 Transition metals such as tin, metal oxides, metal sulfides (e.g., TiO2, FeS, and the like), lithium metal and alloys, or a combination thereof. Examples of active materials include graphite, hard carbon, activated carbon, nano-shaped carbon, silicon, silicon oxides, silicon nanoparticles encapsulated in carbon, or a combination thereof. In some of these embodiments, the anode-active material can be intercalated with lithium (e.g., using pre-lithization methods known in the art).

[0077] Hard carbon is a solid form of carbon that cannot be converted to graphite by heat treatment, even at temperatures up to 3000 °C. It is also known as charcoal or non-graphitizing carbon. Hard carbon is produced by heating carbon-containing starting materials to approximately 1000 °C in the absence of oxygen. Starting materials for hard carbon include polyvinylidene chloride (PVDC), lignin, and sucrose. Other starting materials, such as polyvinyl chloride (PVC) and petroleum coke, produce soft carbon or graphitizing carbon. Soft carbon can be readily converted to graphite by heating to 3000 °C.

[0078] The active anode material is present in the anode in an amount of 30 to 95 wt.%, preferably 40 to 80 wt.% and more preferably 45 to 75 wt.%, based on the total weight of the anode.

[0079] The anode may comprise a conductive additive in amounts of up to 30 wt.%, preferably up to 20 wt.%, and preferably up to 10 wt.%, based on the total weight of the anode. The conductive additive, if present, may also be present in amounts of 1 wt.% or more, preferably 2 wt.% or more, based on the total weight of the anode. The conductive additives listed above (for the capacitor wall and the cathode) may also be used in the anode and are therefore not listed again for brevity.

[0080] The anode may also comprise a polymeric binder in amounts of up to 20 wt.%, preferably up to 15 wt.%, and preferably up to 10 wt.%, based on the total weight of the anode. The polymeric binder, if present, may also be present in amounts of 1 wt.% or more, preferably 2 wt.% or more, based on the total weight of the anode. The anode may also comprise a solid electrolyte in amounts of up to 30 wt.%, preferably up to 25 wt.%, and preferably up to 10 wt.%, based on the total weight of the anode. The solid electrolyte, if present, may also be present in amounts of 1 wt.% or more, preferably 2 wt.% or more, based on the total weight of the anode. Both the polymeric binder and the solid electrolyte used in the anode may be the same as those listed above for the capacitor wall and are therefore not repeated here.

[0081] The separator 304A (see Fig. 2A, Fig. 2B, Fig. 2C or Fig. 2D) comprises a polymer material and / or a ceramic material that is electrically insulating. The separator 304A can be a polymer-based separator embedded with gel electrolytes, a freestanding gel membrane, or a solid electrolyte layer with or without gel electrolytes. Polymer sheets with or without a ceramic coating can be used as the separator. Examples of polymer sheets are polypropylene or polyethylene sheets. Examples of ceramics that can be used to coat the polymer sheets are silicon dioxide (SiO2), aluminum oxide (Al2O3), zirconium dioxide (ZrO2), titanium dioxide (TiO2), or a combination thereof.

[0082] Examples of other high-temperature separators include a nonwoven membrane based on polyimide (PI) nanofibers, a nanoscale polyethylene membrane coated with aluminum oxide and poly(lithium-4-styrenesulfonate), a silicon dioxide-coated polyethylene membrane, a co-polyimide-coated polyethylene membrane, a polyetherimide (PEI) membrane, a membrane made of bisphenol acetone diphthalic anhydride (BPADA) and para-phenylenediamine, an expanded polytetrafluoroethylene membrane reinforced with polyvinylidene fluoride hexafluoropropylene, a sandwich-structured polyvinylidene fluoride / poly(m-phenylene isophthalamide) / polyvinylidene fluoride (PVdF / PMIA / PVdF) membrane, or a combination thereof. These separators can have thicknesses ranging from 1 to 50 micrometers.

[0083] In another embodiment, the separator 306A can be a freestanding gel membrane with a thickness of 10 to 100 micrometers, comprising up to 30 wt.% polymer (e.g. polyacrylonitrile, polyethylene oxide or polyacrylic acid) mixed with 70 to 90 wt.% of a liquid electrolyte. The liquid electrolyte comprises carbonate-based solvents (e.g., ethylene carbonate (EC), γ-butyrolactone (GBL), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), propylene carbonate (PC), or a combination thereof) with a dissolved concentration of lithium salts of more than 0.8 M (e.g., LiTFSI, LiBOB, LiDFOB, LiFSi, LiBeTi, LiPF6, LiBF4, LiAsF6, LiClO4, LiTfO, or a combination thereof) and further comprises at least one of the additives vinylene carbonate (VC), vinylethylene carbonate (VEC), butylene carbonate (BC), fluoroethylene carbonate (FEC), InCl3 ZnCl2, or a combination thereof.

[0084] In another embodiment, a gel electrolyte can be distributed in the electrodes (the anode 303A or the cathode 305A) and / or in the separating layer 304A. In addition to a liquid electrolyte in an amount of 50 to 99.9 wt.%, the gel electrolyte can comprise a polymer host in an amount of 0.1 to 50 wt.%. The polymer host can comprise polyvinylidene fluoride (PVDF), polyvinylidene fluoride hexafluoropropylene (PVDF-HFP), polyethylene oxide (PEO), polypropylene oxide (PPO), polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), polymethyl methacrylate (PMMA), or a combination thereof. Other polymers listed above, used as polymeric binders, can also be used. The liquid electrolytes are listed above and are not repeated here.

[0085] In a process for manufacturing the bipolar solid-state battery cell, a separator film is printed with a material that can act as an anode on one surface and with a material that can act as a cathode on an opposite surface, forming the capacitor wall. Fig. 4A represents an exemplary process for the fabrication of the bipolar solid-state battery cell, in which a bipolar electrode (a separator 304A with the anode 303A and the cathode 305A arranged on opposite surfaces) is coated with a starting material slurry that forms the capacitor wall 306A, 306A1, 308A and 308A1 (see the Fig. 3A and Fig. 3B for a cell of a bipolar solid-state battery with the same structure). In the Fig. 4A A sheet with the bipolar electrode is mounted on a first roller 502 and unwound during the application of a capacitor electrode slurry. The bipolar electrode is unwound from the first roller 502 and wound onto a second roller 508 after the capacitor electrode slurry has been applied to it. On its way from the first roller 502 to the second roller 508, the bipolar electrode passes over rollers 504 and 506, which guide it (hold it in the correct position) so that the nozzles 602 and 604 can deposit the capacitor electrode slurry onto it. The nozzles 602 discharge the slurry for the capacitor walls 306B and 308B, while the nozzle 604 moves back and forth over the bipolar electrode to deposit the slurry for the capacitor walls 306B1 and 308B1. Fig.Figure 4B shows a top view of a bipolar electrode before and after the application of the slurry for the capacitor walls. After the slurry is applied to form the capacitor, the bipolar electrode can be dried to remove any remaining solvent. After solvent removal, the bipolar electrode comprises capacitor walls arranged around the anode and cathode, thus forming the bipolar solid-state battery cell.

[0086] The composition for forming a capacitor wall is described above. To form a capacitor wall slurry, the composition described above can be mixed with one of the carbonate-based solvents mentioned above to form the slurry. The slurry is then filled into nozzles 602 and 604, from where it is directed into the bipolar electrode to form the capacitor walls.

Claims

[1] A bipolar solid-state battery pack comprising a plurality of battery cells, each cell having: a separator; an anode disposed on a first side of the separator; an anode current collector electrically connected to the anode; a cathode disposed on a second side of the separator, the second side being opposite the first side; a cathode current collector in electrical connection with the cathode; a capacitor wall arranged parallel to at least one outer surface of the anode or the cathode, the capacitor wall comprising a capacitor-active material; characterized by , that the capacitor wall is separated from at least one outer surface of the anode or the cathode by an air gap. [2] A bipolar solid-state battery pack according to claim 1, wherein the air gap is up to 0.1 mm thick and the capacitor wall has a wall thickness of 3 to 100 mm. [3] The bipolar solid-state battery pack of claim 1, wherein the capacitor wall contacts an outer surface of the anode or the cathode. [4] A bipolar solid-state battery pack according to claim 1, wherein the capacitor wall contacts an outer surface of the anode or the cathode adjacent to a current collector. [5] A bipolar solid-state battery pack according to claim 1, wherein the capacitor wall is arranged parallel to at least two outer surfaces of the anode or the cathode. [6] A bipolar solid-state battery pack according to claim 1, wherein the capacitor walls are arranged symmetrically around the separator. [7] A bipolar solid-state battery pack according to claim 1, wherein the capacitor walls are arranged asymmetrically around the separator. [8] A method of manufacturing a battery cathode or anode having a capacitor wall, the method comprising: Placing a slurry comprising an active capacitor material on a separator such that a slurry surface is parallel to at least one outer surface of the anode or the cathode; and Drying the slurry to form the condenser wall; characterized by , that the capacitor wall is separated from at least one outer surface of the anode or the cathode by an air gap.

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