Method for producing a solid electrolyte compound for a Si anode, as well as a solid-state Li-ion battery cell and a solid-state Li-ion battery

Abstract

The present invention relates to a method for manufacturing a flat silicon anode-solid electrolyte compound suitable for use in a solid-state battery, and to a flat silicon anode-solid electrolyte compound thus manufactured. The object of the present invention is to provide a method by which a silicon anode-solid electrolyte compound can be manufactured that ensures consistent good electrical contact between cell layers, and said object is achieved by a method for manufacturing a flat silicon anode-solid electrolyte compound suitable for use in a solid-state battery, wherein a multi-layer structure as an active layer of a Si anode is deposited on a porous solid electrolyte by a dry deposition method, the multi-layer structure is subjected to rapid tempering, and a current collector, preferably made of copper, is deposited on the multi-layer structure.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a planar silicon anode - solid electrolyte conjugate suitable for use in a solid - state battery, and to a planar silicon anode - solid electrolyte conjugate manufactured in such a manner.

[0002] The present invention also relates to a solid - state battery cell comprising a cathode and the planar silicon anode - solid electrolyte conjugate of the present invention, and to a solid - state battery comprising at least one solid - state battery cell.

Background Art

[0003] As an introduction, certain principles regarding batteries as electrochemical energy storage devices are restated and defined, along with the related terms used.

[0004] A battery is an electrochemical energy storage device and is classified into primary and secondary batteries.

[0005] A primary battery is an electrochemical power source in which chemical energy is irreversibly converted into electrical energy. A primary battery is, therefore, not rechargeable. A secondary battery, also called a storage battery, on the other hand, is a rechargeable electrochemical energy storage device in which the chemical reactions that occur are reversible, allowing for multiple uses. During charging, electrical energy is converted into chemical energy, and during discharging, it is converted back from chemical energy to electrical energy.

[0006] A "battery" is a general term for cells connected to each other. A cell is a galvanic unit composed of two electrodes, an electrolyte, a separator, and a cell casing. Figure 1 shows an exemplary construction and function of a lithium-ion cell during discharge. Each Li-ion cell consists of two different electrodes 7, 9, an electrode 9 that is negatively charged in the charged state and an electrode 7 that is positively charged in the charged state. The release of energy, in other words, discharge, involves the movement of ions from the negatively charged electrode to the positively charged electrode, so the positively charged electrode is called the cathode 7 and the negatively charged electrode is called the anode 9. The electrodes are each composed of current collectors 2, 8 and the active material applied thereon. First, an ion-conductive electrolyte 4 that enables the required exchange of charges and a separator 5 that ensures electrical separation of the electrodes are arranged between the electrodes.

[0007] A solid-state battery or cell is different from a conventional battery, particularly in terms of the solid electrolyte. The purpose of the electrolyte solution is the conduction of ions between the anode and the cathode.

[0008] Battery cells can be connected by different means. When two battery cells are connected in series, the anode (negative electrode) of one battery cell is connected to the cathode (positive electrode) of the other (assuming discharge). The series connection of battery cells increases the overall voltage, that is, the voltages of the individual cells are added together. When battery cells are connected in parallel, assuming during discharge, all the cathodes (positive electrodes) are connected to each other, and all the anodes (negative electrodes) are the same. In the parallel connection of cells, the capacitance (Ah) of the battery doubles. The same applies to the parallel connection of batteries to form a battery module.

[0009] In currently available lithium-ion batteries, a liquid electrolyte is used to utilize lithium between electrodes (anode and cathode) for energy storage and release. When the potential window for stable operation using an aqueous electrolyte is low, an organic solvent is used. These solvents are highly flammable, increasing the risk of battery ignition. The use of a solid electrolyte with much lower flammability is considered as a solution. A solid electrolyte having the properties of good ionic conductivity combined with good electrical insulation can replace existing liquid electrolytes and separators. At the same time, when using a solid electrolyte, the volume and weight can be reduced due to an increase in energy density, especially when using metallic lithium, and as a result, the packing density can be significantly increased.

[0010] However, the drawbacks of solid electrolytes are their low flexibility and the difficulty of bringing the anode and cathode into contact for efficient ion conduction. Surface contact of the anode with the solid electrolyte is extremely important for good battery performance. In particular, when the powdered starting material of the ceramic electrolyte consists of sintered powder, for example, having a high surface porosity, limited ion contact in the boundary layer between the cathode - electrolyte or electrolyte - anode can significantly reduce the output of the battery. In the case of a large surface current, furthermore, lithium metal with a solid ceramic electrolyte can form dendrites, which can cause the battery to break down. In addition, lithium reacts with the solid electrolyte at the surface, resulting in a decrease in ionic conductivity during operation. Among the various known possibilities for improving electrical contact, examples include the addition of a liquid electrolyte, softening / mixing of the solid electrolyte using a polymer and / or binder, or the use of a relatively soft sulfur - based solid electrolyte such as lithium argyrodite. Argyrodite is a lithium - rich solid compound. The argyrodite system consists of over 100 crystalline solids and extends to solid compounds where, for example, silver is replaced by copper, germanium is replaced by gallium or phosphorus, and sulfur is replaced by selenium. Alternatively, high compression pressures, which are necessary especially when there is volume expansion during battery operation, are used to ensure consistent contact. In commercial construction, however, the high pressures required for this purpose are associated with high cost and complexity.

[0011] For efficient ion conduction within a solid electrolyte, therefore, a high degree of crystallinity is typically required, with corresponding defects in the crystal lattice. In the case of oxide materials such as lithium lanthanum zirconium oxide (LLZO) garnet crystals, this requires a very high crystallization temperature that greatly exceeds the temperatures that need to be observed for the preservation of other battery components, especially the anode. When constructing a solid electrolyte-anode assembly, therefore, it has hitherto been important that the processing step with the highest required temperature is carried out first and the temperature is then lowered as required. With regard to the construction of a solid electrolyte-anode assembly, it is therefore necessary first to manufacture the solid ceramic electrolyte, then to construct the anode, and finally to deposit the copper current collector. In the case of a graphite-based anode, depositing the graphite of this battery on the anode side of the separator is a practice known from the prior art, but this has mainly been used to confirm / prevent the reciprocating movement of sulfur in a lithium-sulfur battery.

Prior Art Documents

Non-Patent Documents

[0012]

Non-Patent Document 1

Non-Patent Document 2

[0013] Accordingly, an object of the present invention is to identify a method by which a silicon anode-solid electrolyte conjugate can be produced, the silicon anode-solid electrolyte conjugate not having the drawbacks identified above.

[0014] Another object of the present invention is to identify a solid-state battery cell or a solid-state battery not having the drawbacks identified above. [Means for Solving the Problems]

[0015] The object is achieved by the method according to independent claim 1 of the method.

[0016] In a method for manufacturing a planar silicon anode-solid electrolyte conjugate suitable for use in a solid-state battery, a multi-layer structure is deposited as an active layer of a Si anode on a porous solid electrolyte by a dry deposition method, the multi-layer structure is subjected to accelerated annealing, and a current collector preferably composed of copper is deposited on the multi-layer structure.

[0017] The porous solid electrolyte is understood to be a layer of sintered powder. The powder is formed from ceramic, which is compressed and heated to form the layer.

[0018] The multi-layer structure is understood to be a layered structure consisting of two or more layers, but the term "multi-layer structure" in the disclosure of the present invention also includes a single layer.

[0019] The method of the present invention is particularly suitable for manufacturing battery cells for a wide variety of different battery applications because it enables the construction of a particulate, fully planar solid electrolyte-silicon anode using an auxiliary agent to stabilize the multi-layer construction of the active layer of the anode. For example, through the use of dry manufacturing methods such as sputtering or electron beam evaporation, not only can a multi-layer structure be directly deposited planar as the active layer of the anode on the solid electrolyte, but it is also possible to apply an additional intermediate layer for the stabilization of the solid electrolyte / anode interface without additional cost and complexity. Accelerated annealing enables controlled targeting of energy input into the layer.

[0020] In one configuration of the method of the present invention, an intermediate layer for the stabilization between the solid electrolyte and the active layer of the Si anode is deposited between the solid electrolyte and the multi-layer structure.

[0021] In particular, it is advantageous that the silicon anode-solid electrolyte conjugate is manufactured in the reverse order to existing methods. As a result, it becomes possible to directly apply the anode to the solid electrolyte, and thus optimal ionic contact to the solid electrolyte, which is usually difficult to achieve, can be realized.

[0022] When the manufacturing method is initiated using a solid electrolyte, the current collector can be optimized on the anode side such that it no longer necessarily has to perform a load-bearing function. As a result, the thickness of the copper current collector material can be reduced to the current density actually required in the application, and thus the weight and layer thickness can be reduced without any adverse effect on the heat temperature transfer. Generally, a significant weight reduction and thus an increase in the weight energy density can be achieved.

[0023] The planar deposition process in the dry deposition method means that the manufacturing method of the present invention ensures consistent layer construction. The basic processing steps give rise to a wide range of parameters that can be optimized by means appropriate for the corresponding application. In particular, rapid thermal annealing brings extremely important advantages through a targeted energy input. Using rapid thermal annealing, the energy input can be controlled layer by layer so as to enable the realization from a functionalized Si anode to an all-solid-state battery (ASSB).

[0024] In a further configuration of the method of the present invention, therefore, the multi-layer structure is deposited layer by layer and the multi-layer structure is formed from at least one layer of metal and / or silicon, or from a mixed system consisting of silicon mixed with at least one metal.

[0025] The multi-layer structure is formed from at least one layer. A layer refers to a deposited layer of the anode's active material, and depending on the layer thickness, the active layer of the electrode / anode can be constructed from one or more layers. At least one layer can, on the one hand, be formed from at least one metal and / or silicon. In that case, silicon and at least one metal are alternately applied by deposition of separate layers of the materials. A layer is thus formed from at least one layer of at least one applied metal and a layer of silicon, and in order to obtain the target thickness of the anode, a plurality of layers are embodied in the multi-layer structure. Alternatively, at least one layer may also be formed by a mixed system, the mixed system consisting of silicon mixed with at least one metal. This mixture of at least one metal and silicon, usually in powder form, is deposited until the active layer reaches its target thickness.

[0026] Lithium intercalation is accompanied by volume expansion, but the pulverization of the silicon layer of the Si anode does not occur by the mixing of metals and the use of the multi-layer structure. The mixing of metals leads to the formation of an alloy that has a reduced hardness compared to pure silicon. At the same time, a very high electrical conductivity of silicon is brought about compared to graphite. Despite the mixing of metals, a specific overall capacity of more than 2000 mAh / g is ensured.

[0027] The stability and high electrical conductivity of the silicon anode are maintained by performing a heterogeneous construction involving the formation of a conductive matrix of a metal or metal silicide surrounding the amorphous regions of silicon.

[0028] In one configuration of the manufacturing method of the present invention, the metal is formed from at least one of the materials of manganese (Mn), cobalt (Co), iron (Fe), titanium (Ti), nickel (Ni), aluminum (Al), tin (Sn), gold (Au) and / or silver (Ag), and / or a mixture of these materials.

[0029] In different configurations of the manufacturing method of the present invention, the dry deposition method is a PVD process, for example, sputtering. Preferred methods are sputtering and electron beam evaporation. Similarly, CVD (chemical vapor deposition) methods such as plasma-enhanced CVD (PECVD), or PVD (physical vapor deposition) methods such as thermal evaporation or pulsed laser deposition (PLD) are possible.

[0030] In yet another different configuration of the manufacturing method of the present invention, the accelerated annealing controls the deposition layer of the multilayer structure and / or the layer of the Si anode - solid electrolyte junction, or the energy input to other solid-state battery cells and / or solid-state batteries.

[0031] Through the use of accelerated annealing, the planar construction of the Si anode - solid electrolyte junction of the present invention can be carried out first in the order presented above, i.e., solid electrolyte - active layer - current collector, and then in the reverse order starting with the current collector, followed by the active layer of the anode, and further processing and / or construction of the solid electrolyte by PVD methods. Since the contact at the solid electrolyte - anode interface is extremely important for the performance of the battery, a thin layer is sufficient to provide a stable contact. The required crystallinity or ionic conductivity in the solid electrolyte can be brought about by accelerated annealing.

[0032] In other words, in different configurations of the method of the present invention, the steps of the method for manufacturing a planar silicon anode - solid electrolyte junction are specifically such that the multilayer structure is preferably deposited as an active layer on a current collector of a copper Si anode by a dry deposition method, and then accelerated annealing is performed with a controlled and adjustable energy input to the multilayer structure of the Si anode. The intermediate layer is deposited on the multilayer structure for stabilization between the solid electrolyte and the active layer of the Si anode, the solid electrolyte is deposited, and the solid electrolyte is subjected to accelerated annealing for crystallization of the solid electrolyte, in the reverse order.

[0033] In one configuration of the manufacturing method of the present invention, the rapid annealing is flash lamp annealing, and is carried out by a flash lamp having a flash light duration in the range from 0.2 to 20 ms and an energy density in the range from 0.3 to 160 J / cm 2 and also by using preheating or cooling in the range from 4°C to 200°C.

[0034] In a different configuration of the manufacturing method of the present invention, the rapid annealing is laser annealing, and is carried out by a laser having an annealing time in the range from 0.01 ms to 100 ms and an energy density in the range from 0.1 to 100 J / cm 2 established by the scanning speed of the locally heated portion, and also by using preheating or cooling in the range from 4°C to 200°C.

[0035] The temperature range from 4°C to 200°C described above relates to the surface temperature of the substrate or layer to be annealed.

[0036] It has been revealed that the effect of rapid annealing differs depending on the deposition of different materials in the active layer. This cause is considered to be a variety of chemical events related to silicon. As a result, different structures, such as the columnar structure in the case of nickel, can be formed in the generated anode layer. Furthermore, different silicides that also intercalate lithium can be formed, in contrast to Cu silicide in which the ability to intercalate lithium is negligibly small or zero. The advantage of utilizing the described differences is that it can be used to control the volume expansion of silicon in the intercalation of lithium. As a result, the stability of the operation of the battery is significantly improved.

[0037] In the case of titanium, in a proper phase, a Ti silicide that can have a Li intercalation ability is formed (see Xu, J. et al., Preparation of TiSi2 Powders with Enhanced Lithium-Ion Storage via Chemical Oven Self-Propagating High-Temperature Synthesis. Nanomaterials 11, 2279 (2021)). This has the advantage that there is no clear boundary surface between Li-active and Li-inactive, and as a result, there is good electrical contact even during cycling. Furthermore, metals such as aluminum, for example, do not form any compounds with silicon, that is, do not form any silicides. As a result, these metals are mixed in silicon and the electrical conductivity is increased. In the accelerated annealing process, the morphology and hardness of the silicon-metal layer can be further improved compared to hard pure silicon.

[0038] The reaction forced by accelerated annealing between silicon particles and metal particles in the active layer of the Si anode is a non-equilibrium process, which is only achievable in the range of ms and thus requires the use of a flash lamp or laser.

[0039] The heating gradient achieved in accelerated annealing is within the range of 10 4 ~10 7 K / s. For this purpose, flash lamp annealing utilizes the spectrum in the visible light wavelength range, while laser annealing uses discrete wavelengths in the spectral range from infrared (IR) to ultraviolet (UV).

[0040] Regarding the placement surface, the objective is achieved by the planar silicon anode-solid electrolyte junction described in independent claim 10.

[0041] In the case of the planar silicon anode - solid electrolyte junction of the present invention manufactured by the method according to claims 1 to 9 of the foregoing method, the solid electrolyte preferably consists of an oxide material, more particularly a garnet - structured oxide, a NASICON - type phosphate glass - ceramic or an oxynitride.

[0042] Garnet - structured oxides structurally belong to nesosilicates, such as, for example, the widely studied lithium - lanthanum - zirconium oxide (LLZO). NASICON - type phosphate glass - ceramics are named after the chemical structure of NaZr2(PO4)3 and have high ionic conductivity for lithium ions. Examples include LAGP: lithium aluminum germanium phosphate and LATP: lithium aluminum titanium phosphate. Oxynitrides are oxides in which some oxygen atoms are replaced by nitrogen, resulting in a large number of defects in the lattice, thus leading to high ionic conductivity, such as xLi2O:yP2O5:zPON, abbreviated as LiPON. LiPON can be produced by sputtering of Li3PO4 in a reactive N2 plasma.

[0043] The Si anode - solid electrolyte junction of the present invention includes a solid electrolyte realized from an oxide material, particularly, for example, a garnet - structured oxide such as LLZO, a NASICON - type phosphate glass - ceramic such as LATP or LAGP, and an oxynitride such as LiPON. Oxide materials require a high degree of crystallinity for efficient ionic conduction and thus need high processing temperatures. The processing temperatures are in the region of room temperature for the LiPON sputter layer, up to 1230 °C for well - crystalline sintered LLZO ceramics, and about 700 °C for the glass transition temperature of NASICON ceramics.

[0044] The described oxide materials are particularly suitable for use in ASSBs because they have an ionic conductivity exceeding 1 mS / cm (millisiemens per centimeter) and are very stable both thermally and chemically.

[0045] In different configurations of the Si anode - solid electrolyte junction of the present invention, the solid electrolyte has a crystallinity with high ionic conductivity that can be targeted and adjusted by accelerated annealing.

[0046] Accelerated annealing enables the construction of the planar Si anode - solid electrolyte junction as described above. Surface contact enables efficient ionic conduction between the active layer of the Si anode and the solid electrolyte. An artificial SEI as an intermediate layer between the Si anode and the solid electrolyte can additionally improve the contact between the two layers. Otherwise, the contact between the Si anode and the solid electrolyte is insufficient, and in particular, in the case of a Li metal anode, deterioration of the surface of the solid electrolyte occurs.

[0047] An object of the present invention is also a solid - state battery cell comprising a cathode and a planar silicon anode - solid electrolyte junction manufactured by the method according to claims 1 to 9, wherein the silicon anode, the solid electrolyte and the cathode are embodied in a planar construction, which is achieved by the solid - state battery cell.

[0048] The manufacture of a complete solid - state battery cell or solid - state battery by a planar deposition method with a solid electrolyte is particularly advantageous because the planar construction enables the manufacture of the solid electrolyte on a planar Si anode and also enables the direct application of the Si anode and the copper conductor to the solid electrolyte.

[0049] In yet another different configuration of the solid - state battery cell of the present invention, the active layer as the cathode is formed from LiFePO4, LiMnO2 or LiCoO2, and preferably a current collector composed of aluminum is formed on the active layer as the cathode.

[0050] Materials that are particularly suitable for the cathode are those that enable dry deposition. Known techniques from the prior art include those that deposit LiFePO4 layer by layer as the cathode. The specified material can be fabricated in planar form by sputtering (see 1. Bunting, A., Uhlenbruck, S., Sebold, D, Buchkremer, H.P. & Vaßen, R., Three-Dimensional, Fibrous Lithium Iron Phosphate Structures Deposited by Magnetron Sputtering. ACS Appl. Mater. Interfaces 7, 22594-22600 (2015), or 2. Fischer, J. et al., Development of thin film cathodes for lithium-ion batteries in the material system Li-Mn-O by r.f. magnetron sputtering. Thin Solid Films 528, 217-223 (2013), which are particularly suitable for the production of laminates).

[0051] In one configuration of the solid-state battery cell of the present invention, the anode-side construction comprising a Si anode-solid electrolyte junction and a Si anode-copper current collector junction, and also the cathode-side construction comprising a solid electrolyte-cathode-aluminum current collector junction and / or a catholite-aluminum current collector junction can be manufactured and constructed separately from each other, and the Si anode-solid electrolyte junction, the Si anode-copper current collector junction, and also the solid electrolyte-cathode-aluminum current collector junction and / or the catholite-aluminum current collector junction are configured to be connectable to each other in the final fabrication process via their respective bulk contacts.

[0052] As a result of the method of the present invention, first, it is possible to realize the manufacturing order of the layers of a complete solid-state battery cell in a different order of manufacturing, and even to manufacture all parts of the solid-state battery cell separately from each other, with the feature that the transition contact is already completely formed. The transition contact refers to, for example, the interface between the Si anode and the solid electrolyte. Thus, it is only necessary to assemble the materials that are later formed evenly. In the case of the anode-side construction, first, the active layer of the Si anode can be directly applied to the solid electrolyte by a planar construction, and then the copper current collector can be deposited, or else, first, the planar active layer can be deposited on the Cu current collector, and then the solid electrolyte. For the cathode-side construction, there already exist methods for bonding the solid electrolyte and the cathode to each other, i.e., for applying the active layer of the cathode to the solid electrolyte and then the Al current collector, or for depositing the active layer of the cathode on the Al current collector and then the solid electrolyte. The layer configurations, i.e., the Si anode - solid electrolyte and / or Cu current collector - Si anode and / or solid electrolyte - cathode - aluminum current collector, can here be manufactured separately from each other in order to simplify production, and for the production or formation of the solid-state battery cell, these layer configurations are connected / joined to each other via their respective bulk contacts. The bulk contact refers to, for example, the bonding of the active layer part in the context of the connection between the Si anode - solid electrolyte and the Cu current collector - Si anode layer configurations, and the bonding via the solid electrolyte in the context of the connection between the Si anode - solid electrolyte and the solid electrolyte - cathode - aluminum current collector layer configurations. The bonding is optionally maintained by a temperature process.

[0053] The object of the present invention is also achieved by a solid-state battery consisting of two or more solid-state battery cells, wherein the two or more solid-state battery cells are applied to each other in a planar manner and stacked on top of each other by the provided manufacturing method. The contacts can be embodied as being connected to each other in parallel and / or in series.

[0054] The present invention will be described in more detail below with reference to exemplary embodiments.

[0055] The content of the drawings is as follows.

Brief Description of the Drawings

[0056]

Figure 1

Figure 2a

Figure 2b

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0057] The production of the solid electrolyte 11 typically requires a large energy input to produce a crystal structure with high ionic conductivity. The method of the present invention is suitable for this, and in order to achieve a stable anode structure, the anode structure 9 is applied to the solid electrolyte 11 (FIG. 2a), or the solid electrolyte 11 is applied to the current collector 2 using the active layer 9, and the anode 9 is formed together (FIG. 2b). Accelerated annealing, particularly flash lamp annealing, can then be utilized to crystallize the solid electrolyte layer through a targeted energy input without causing significant damage to the anode (from FIG. 2b).

[0058] The method of the present invention advantageously enables the treatment of the silicon anode - solid electrolyte junction 10 to be carried out in two directions. The multi - layer structure 9 as the active layer of the anode is deposited on the solid electrolyte 11 by a dry process, and then the current collector 2 is deposited (FIG. 2a), or first, the multi - layer structure 9 for the active layer of the anode is deposited on the current collector 2, and then the solid electrolyte 11 is deposited, i.e., in the reverse order (FIG. 2b). The layer or layers are stabilized by accelerated annealing. This makes it possible to manufacture the solid - state electrolyte separately from the production of the anode.

[0059] In the first variant (FIG. 2a), during the manufacturing process, a Si anode composed of at least one layer of metal and / or silicon, or a mixed system composed of silicon mixed with at least one metal, is deposited in particulate form together with an additional layer. The direct application of the anode 9 to the solid electrolyte 11 enables optimal ionic contact to the solid electrolyte 11, which is usually difficult to achieve. It is required that the processing parameters necessary for this purpose, and also the annealing treatment by flash lamp annealing, have no substantial impact on the existing solid electrolyte 11. Finally, the current collector 2 can be applied to the "solid electrolyte and Si anode" structure with an appropriate layer thickness.

[0060] As a result of the manufacturing method of the present invention (see Fig. 3), the anode-side current collector 2 in the process can be optimized in terms of electrical conductivity, layer thickness (e.g., 3 μm), and weight since it does not need to perform a load-bearing function. The attachment of the current tap can be realized, for example, by application by rotation of a diverting tab of appropriate thickness directly to the anode 9 or to the anode 9 prepared by surface deposition of metal to reduce resistance, which requires surface contact. Further deposition of the Si anode 9 can be additionally realized independently of the substrate 2. With the solid electrolyte 11, the cathode 7, the current collector 8 of the cathode, and an appropriate method for further deposition of further battery cell construction, any desired overlap (Fig. 6) of cells composed of a plurality of cells 14 can be constructed. Therefore, the capacity of the solid-state battery 15 can also be easily realized and / or adjusted. This stacking of the anode 9 / solid electrolyte 11 / cathode 7 enables a highly integrated implementation method for the assembly of all-solid-state batteries.

[0061] The intermediate layer 16 (see Fig. 4) between the anode 9 and the solid electrolyte 11 plays a role in interface engineering processing and enables the targeted application of the anode 9 to the solid electrolyte 11 without additional cost and complexity.

[0062] Figure 5 shows a manufacturing variant for a solid-state battery cell 14 according to the method of the present invention for manufacturing a Si anode - solid electrolyte junction 10. Using this exemplary embodiment, both the Si anode - solid electrolyte junction 10 and the Si anode - copper current collector junction 20, as well as the solid electrolyte - cathode - aluminum current collector junction and / or the catholite - aluminum current collector junction 19, are manufactured separately from each other. For the manufacture or formation of the solid-state battery cell, the separately manufactured layer configurations 10, 20, 19 are connected to each other via their respective bulk contacts. The bulk contact refers to the active layer 9 in the case of, for example, the Si anode - solid electrolyte junction 10 and the Cu current collector - Si anode junction 20, and to the solid electrolyte 11 in the case of the connection between the Si anode - solid electrolyte 10 and the solid electrolyte - cathode - aluminum current collector 19. The catholite 17 refers to a mixture of the cathode 7 with the solid electrolyte 11.

[0063] The present invention enables the realization of the manufacturing sequence of the layers of a solid-state battery cell in a different order of manufacture, and the manufacture of parts of a solid-state battery cell having defined interfaces even separately from each other, and then simply connecting them to each other in a final process.

[0064] The manufacture of the layer stack represented in Figure 6 for the solid-state battery 15 can be accomplished by a first variant of the manufacturing method of the silicon anode - solid electrolyte junction 10, in which the active layer 9 of the anode and the current collector 2 are applied to the solid electrolyte 11, or by a second variant of the manufacturing method for the silicon anode - solid electrolyte junction 10, in which the active layer 9 as the anode and then the solid electrolyte 11 are applied to the current collector 2, or by a combination of both variants.

[0065] The direct application of the Si anode 9 to the solid electrolyte 11 enables stacking in a single process, rather than in multiple facilities or implementation methods as before. This brings new possibilities for performance improvement by targeting and influencing the interface. The number of manufacturing facilities is reduced.

[0066] Since the solid electrolyte, particularly the solid ceramic electrolyte, is very thick and hard, the stability required for the anode or the solid-state battery cell can be achieved by the solid electrolyte rather than by the current collector of the anode as before. Metal savings can accordingly be achieved. The focus of optimization can thus be directed towards the electrical contact between the interfaces of the individual battery structures.

[0067] Considering that the interface is extremely important in the solid-state battery 15 compared to the bulk properties, the design and production of the interface are of utmost importance.

[0068] The stacking of individual solid-state battery cells 14 is necessary to achieve a sufficient overall capacity for the solid-state battery 15 as shown in Figure 6. Heretofore, this has been impossible because there has been no reversible production means for constructing the Si anode - solid electrolyte junction 10 starting from the solid electrolyte 11. This is only made possible through the planar construction of the solid electrolyte 11 and the planar anode, rapid annealing, and the use of dry deposition processes.

Explanation of Symbols

[0069] 1 Lithium-ion battery 2 Anode-side current collector 3 SEI, solid - electrolyte interphase 4 Electrolyte 5 Separator 6 Conductive interphase 7 Cathode, positive electrode 8 Cathode-side current collector 9 Anode, negative electrode, active layer, or multi-layer structure 10 Silicon anode - solid electrolyte junction 11 Solid electrolyte 12 Fabrication sequence 1 13 Fabrication sequence 2 14 Solid-state battery cell 15 Solid-state battery 16 Intermediate layer, artificial solid electrolyte interface 17 Catholite 19 Solid electrolyte-cathode-aluminum current collector assembly, and / or cathodolite-aluminum current collector assembly 20 Si anode-copper current collector assembly

Claims

1. A method for producing a planar silicon anode-solid electrolyte assembly (10) suitable for use in a solid-state battery (15), comprising: depositing a multi-layer structure as an active layer of a Si anode (9) on a porous solid electrolyte (11) by a dry deposition method, the porous solid electrolyte (11) consisting of an oxide material, or a garnet-structure oxide, a NASICON-type phosphate glass ceramic, or an oxynitride; subjecting the multi-layer structure (9) to accelerated annealing; depositing a current collector (2) consisting of copper on the multi-layer structure (9), the accelerated annealing being flash lamp annealing, with a flash light duration ranging from 0.2 to 20 ms and a current density of 0.3 to 160 J / cm 2 . and / or preheating or cooling in the range of 4°C to 200°C, or the accelerated annealing is laser annealing, characterized in that the accelerated annealing can be performed by a laser having an annealing time in the range of 0.01 ms to 100 ms by establishing a scanning speed of the localized heating point and an energy density in the range of 0.1 to 100 J / cm2, and / or preheating or cooling in the range of 4°C to 200°C.

2. 2. The method for manufacturing a planar silicon anode-solid electrolyte joint (10) according to claim 1, characterized in that an intermediate layer (16) for stabilization between the solid electrolyte (11) and the active layer of the Si anode (9) is deposited between the solid electrolyte (11) and the multi-layer structure (9).

3. 10. The method for manufacturing a planar silicon anode-solid electrolyte assembly (10) according to claim 1, characterized in that the multi-layer structure (9) is deposited layer by layer, the multi-layer structure (9) being formed from at least one layer of metal and / or silicon, or from a mixed system consisting of silicon mixed with at least one metal.

4. 4. The method for manufacturing a planar silicon anode-solid electrolyte joint (10) of claim 3, wherein the metal is formed from at least one of manganese, Mn, cobalt, Co, iron, Fe, magnesium, Mg, titanium, Ti, nickel, Ni, aluminum, Al, tin, Sn, gold, Au, and / or silver, Ag, and / or mixtures of these materials.

5. 2. The method for manufacturing a planar silicon anode-solid electrolyte joint (10) according to claim 1, characterized in that the dry deposition method is a PVD process, such as sputtering or electron beam evaporation.

6. A method for producing a planar silicon anode-solid electrolyte assembly (10) suitable for use in a solid-state battery, comprising: depositing a multilayer structure as an active layer on a current collector (2) of the Si anode (9) of copper by a dry deposition method, and then subjecting the multilayer structure of the Si anode (9) to accelerated annealing with controlled and adjustable energy input; depositing an intermediate layer (16) on the multilayer structure (9) for stabilization between a solid electrolyte (11) and the active layer of the Si anode (9); depositing the solid electrolyte (11) from an oxide material or consisting of a garnet-structure oxide, a NASICON-type phosphate glass ceramic, or an oxynitride; and subjecting the solid electrolyte (11) to accelerated annealing for crystallization of the solid electrolyte (11), the accelerated annealing being a flash lamp annealing with a flash light duration ranging from 0.2 to 20 ms and an energy input of 0.3 to 160 J / cm2. and / or preheating or cooling in the range of 4°C to 200°C, or the accelerated annealing is laser annealing, characterized in that the accelerated annealing can be performed by a laser having an annealing time in the range of 0.01 ms to 100 ms by establishing a scanning speed of the localized heating point and an energy density in the range of 0.1 to 100 J / cm2, and / or preheating or cooling in the range of 4°C to 200°C.

7. 10. The method for producing a planar silicon anode-solid electrolyte joint (10) according to claim 1 or 6, characterized in that the energy input to the deposited layers of the multi-layer structure (9) and / or the layers of the silicon anode-solid electrolyte joint (10) is controlled by the accelerated annealing.

8. A planar silicon anode-solid electrolyte assembly (10), characterized in that the solid electrolyte (11) is made of an oxide material, such as a garnet-structure oxide, a NASICON-type phosphate glass ceramic, or an oxynitride.

9. 9. The planar silicon anode-solid electrolyte assembly (10) of claim 8, wherein the solid electrolyte (11) has a crystallinity with high ionic conductivity that can be targeted and adjusted by the accelerated annealing.

10. A solid-state battery cell (14) comprising a cathode (7) and a planar silicon anode-solid electrolyte assembly (10), characterized in that the silicon anode (9), the solid electrolyte (11) and the cathode (7) are embodied in a planar structure.

11. The cathode (7) is LiFePO ４ , LiMnO ２ or LiCoO ２ 11. A solid-state battery cell (14) according to claim 10, characterized in that the active layer is formed from an active layer of SiO 2 and a current collector (8) made of aluminum is formed on the active layer as a cathode.

12. 11. The solid-state battery cell (14) according to claim 10, characterized in that the anode-side assembly comprising the Si anode-solid electrolyte assembly (10) and the Si anode-copper current collector assembly (20), and also the cathode-side assembly comprising the solid electrolyte-cathode-aluminum current collector assembly and / or the catholyte-aluminum current collector assembly (19) can be manufactured and assembled separately from each other, and the Si anode-solid electrolyte assembly (10) and the Si anode-copper current collector assembly (20), and also the solid electrolyte-cathode-aluminum current collector assembly and / or the catholyte-aluminum current collector assembly (19) are configured to be connectable to each other in a final fabrication step via their respective bulk contacts (9, 11).

13. 11. A solid-state battery (15) comprising two or more solid-state battery cells (14) according to claim 10, wherein the two or more solid-state battery cells (14) are embodied as being stacked on top of each other in a plane, and the contacts are embodied as being connected to each other in parallel and / or in series.

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