METHOD FOR MANUFACTURING AN ELECTRODE, ELECTRODE, ALKALI BATTERY AND USES OF THE ALKALI BATTERY

Description

[0001] A method for manufacturing an electrode for a galvanic cell, an electrode for a galvanic cell, a galvanic cell, and uses of the galvanic cell are presented. The method comprises applying a separator membrane to a flat electrode, creating a space between the flat electrode and the separator membrane, followed by applying a liquid containing a specific material to the separator membrane. The liquid containing the material penetrates, via capillary action, at least the pores of the separator membrane, the space between the flat electrode and the separator membrane, and the pores of the flat electrode. The liquid is then evaporated.The method makes it possible to provide an electrode in a simple and cost-effective way that has a high energy density at the cell level as well as high chemical, electrochemical and mechanical stability, thus exhibiting high cycle stability and enabling high operating currents.

[0002] Commercial alkaline batteries (e.g., lithium-ion batteries with a graphite anode) have reached a material-related limit in terms of possible energy density. In addition to increasing performance requirements, high material costs due to processing and supply necessitate alternative anode designs.

[0003] To improve the energy density of galvanic cells, the literature has suggested using lithium metal, lithium metal alloys, or sodium metal alloys (e.g., a LiAl alloy or a NaAl alloy) instead of a commercially available graphite-based negative electrode (anode). However, the use of pure metallic lithium or metal alloys results in insufficient cycle stability and is associated with high manufacturing and material costs. Therefore, pretreatment measures at the electrode-electrolyte interface are essential for the accessibility and stabilization of these promising high-capacity electrode materials.

[0004] CN 112670673 A discloses a separator coated with an active layer, wherein the active layer contains an organic binder, inorganic particles, and a lithium conducting salt. To produce an electrode, the finished separator is applied to a conductive substrate, resulting in an electrode whose mechanical stability and possible operating currents or achievable energy density could be further improved. The use of inorganic particles, particularly when using a lithium foil as the conductive substrate, makes the electrode production complex and costly.

[0005] Based on this, the object of the present invention was to provide a method for producing an electrode for a galvanic cell, an electrode for a galvanic cell, and a galvanic cell itself, which does not exhibit the disadvantages of the prior art. In particular, the method was to be simple and provide, in a cost-effective manner, an electrode which, when used in a galvanic cell, exhibits high energy density at the cell level, high chemical, electrochemical, and mechanical stability, and thus high cycle stability and enables high operating currents. Furthermore, uses of the galvanic cell were to be proposed.

[0006] The problem is solved by the method with the features of claim 1, the electrode with the features of claim 10, the galvanic cell with the features of claim 17, and the use with the features of claim 18. The dependent claims describe advantageous embodiments.

[0007] According to the invention, a method for manufacturing an electrode for a galvanic cell is provided, comprising a) Providing a planar electrode, wherein the planar electrode has a surface; b) Applying a first surface of a separator membrane to the surface of the planar electrode, such that a space is formed between the surface of the planar electrode and the first surface of the separator membrane; c) Applying a liquid to a second surface of the separator membrane, which is opposite the first surface, wherein the liquid contains a solvent and a material selected from the group consisting of polymers, inorganic particles, organic particles and combinations thereof, wherein the liquid, with its solvent and its material, penetrates by capillary action at least into the pores of the separator membrane, into the space between the surface of the electrode and the first surface of the separator membrane and into pores of the surface of the planar electrode;and d) evaporation of the solvent of the liquid, forming an electrode which contains the material of the liquid in the space between the surface of the electrode and the first surface of the separator membrane and in at least part of the pores, wherein the material makes planar contact with the surface of the electrode and the first surface of the separator membrane.

[0008] The method according to the invention can be carried out in a simple and cost-effective manner. Furthermore, the method according to the invention can be used to produce an electrode that exhibits a high energy density at the cell level, high chemical, electrochemical, and mechanical stability, and thus high cycle stability and enables high operating currents. This is because, after the liquid evaporates, the liquid material is present in the pores of the separator membrane, in the space between the surface of the electrode and the first surface of the separator membrane, and in the pores of the surface of the planar electrode. This penetration of the liquid material creates an enriched material layer in the pores of the separator membrane, in the space, and in the pores of the planar electrode.This enriched material layer, upon addition of a liquid electrolyte, ensures optimal electrolyte distribution at the interface and within the pores of the planar electrode by creating a concentration gradient. Additionally, the enriched material layer provides a porous support structure that promotes the formation of an immobilized, stable protective layer (solid electrolyte interface, SEI) between the electrolyte and the electrode surface. Furthermore, the material of the layer mediates strong adhesion between the separator membrane and the planar electrode. These aspects give the electrode high cycle stability, enabling the use of electrode materials with high specific capacitance (such as a LiAl alloy), which are critical to stability. In this way, high energy densities at the cell level can be achieved.

[0009] The material is suitable for swelling into a gel with a liquid electrolyte. This leads to improved electrolyte distribution and thus ion conductivity at the surface of the planar electrode. Since the material is also present in the pores of the separator membrane and in the pores of the surface of the planar electrode, the liquid electrolyte is also present in the pores of the separator membrane and the surface of the planar electrode after the swelling process. This leads to improved ion transport from the secondary surface of the separator membrane to the surface of the planar electrode, which increases the energy density compared to known electrodes for galvanic cells. After swelling of the material with the liquid electrolyte, a so-called gel forms in the space between the separator membrane and the planar electrode and in the pores of the separator membrane and the surface of the electrode.The "solid electrolyte interface" (SEI) is strongly fixed and immobilized to the respective surfaces. The resulting stable protective layer increases the chemical and electrochemical stability of the electrode and provides a mechanical barrier that slows down potential dendrite growth. This gives the electrode higher cycle stability and operational reliability compared to similar electrodes for galvanic cells.

[0010] The planar electrode used in the process can contain or consist of an alkali metal, optionally coated with a metal selected from the group consisting of stainless steel, nickel, copper, indium, aluminum, and combinations thereof. The alkali metal is preferably selected from the group consisting of lithium, sodium, and combinations thereof. The advantage of lithium is its high specific capacity of > 3000 Ah / kg (10 times that of commercial graphite anodes), its low anode potential of 0 V vs. Li / Li+, and the resulting very high energy density at the cell level.

[0011] The planar electrode used in the process may furthermore contain or consist of carbon, preferably a carbon selected from the group consisting of graphite, graphene and combinations thereof.

[0012] Apart from that, the planar electrode used in the process may contain or consist of silicon, a silicon alloy and / or a silicon composite.

[0013] Furthermore, the planar electrode used in the process can contain or consist of a metal selected from the group consisting of stainless steel, nickel, copper, indium, and aluminum, preferably aluminum. One advantage of aluminum is that it is less expensive than other suitable alloying elements such as indium or silicon. Further advantages of aluminum lie in its low anode potential (U_anode), which, in a LiAl alloy, is approximately 0.3 V vs. Li / Li +< (comparable to the potential of the commercially used graphite anode) and maximizes the cell voltage U = U_cathode - U_anode. Moreover, aluminum can provide a high specific capacity (e.g., in the LiAl alloy form, approximately 993 Ah / kg, which is about three times that of graphite). Thus, the available energy density E at the cell level (E = C * U) is very high in the case of an aluminum-based anode.The aluminium is optionally alloyed, preferably with at least one element selected from Group II of the periodic table, Group III of the periodic table, Group IV of the periodic table, a transition group of the periodic table and combinations thereof, wherein the at least one element is preferably selected from the group consisting of magnesium, indium, zinc, tin, silicon, manganese and combinations thereof.

[0014] The planar electrode used in the process may furthermore contain or consist of a cathode material, preferably selected from the group consisting of nickel-manganese-cobalt oxide, lithium iron phosphate, lithium manganese oxide, lithium-nickel-manganese oxide, lithium nickel oxide, lithium cobalt oxide, lithium aluminum nickel oxide, lithium manganese phosphate, lithium iron manganese phosphate and combinations thereof.

[0015] The planar electrode used in the process can have a thickness, in a direction perpendicular to the surface of the planar electrode, in the range of 5 to 100 µm, preferably 10 to 50 µm, particularly preferably 20 to 40 µm.

[0016] Furthermore, the planar electrode used in the process can have a surface structure on its surface. The surface structure preferably has a structure depth in the range of 1 nm to 100 µm, wherein the surface structure is particularly preferably selected from the group consisting of embossed surface structures, brushed surface structures, patterned surface structures, grooved surface structures and combinations thereof.

[0017] The separator membrane used in the process can consist of at least one layer, optionally at least one further layer (i.e. at least two layers).

[0018] The at least one layer (optionally also at least one further layer) can contain or consist of an electrically insulating material, wherein the material preferably has a specific electrical resistance of ≥ 10 10< Ω·mm 2< / m, particularly preferably ≥ 10 11< Ω·mm 2< / m.

[0019] Furthermore, the at least one layer (optionally also at least one further layer) can contain or consist of an organic material, preferably containing or consisting of a polymeric plastic. The polymeric plastic is particularly preferably selected from the group consisting of polyolefin, fluoropolymer, polyamide, polyimide and combinations thereof, wherein the polymeric plastic is particularly selected from the group consisting of polyethylene, polypropylene, polytetrafluoroethylene, polyamide, para-aramid, polyimide and combinations thereof.

[0020] Furthermore, at least one layer (optionally at least one additional layer) can contain or consist of an inorganic material, preferably a ceramic material. The ceramic material is specifically selected from the group consisting of oxide ceramics, carbide ceramics, nitride ceramics, and phosphate ceramics. The oxide ceramic can be aluminum oxide (Al₂O₃). Al₂O₃ has the advantage of being cost-effective compared to solid electrolyte salts such as lithium phosphorus sulfide. Furthermore, Al₂O₃ forms an inert protective layer and thus prevents undesirable side reactions. In addition, Al₂O₃ (in particle form) provides a porous structure, which improves electrolyte distribution and creates a SEI precursor effect.

[0021] Apart from that, at least one layer (optionally at least one further layer) can contain or consist of an ion-conducting material.

[0022] Furthermore, the at least one layer (optionally also at least one further layer) can have a thickness, in a direction perpendicular to the surface of the planar electrode, in the range of 1 µm to 300 µm, preferably in the range of 1 µm to 100 µm.

[0023] Furthermore, the at least one layer (optionally also at least one further layer) can have a porosity in the range of 30% to 70%, preferably in the range of 40% to 60%, particularly preferably in the range of 45% to 50%.

[0024] The liquid used in the process can contain a solvent having a boiling point of ≤ 156 °C, preferably ≤ 80 °C, and particularly preferably ≤ 56 °C, at atmospheric pressure. Furthermore, the liquid used in the process can contain a solvent having a vapor pressure of ≥ 3 hPa, preferably ≥ 58 hPa, and particularly preferably ≥ 246 hPa, at 20 °C. The solvent can be selected from the group consisting of acetone, DEC, DMAC, 3-hexanone, THF, butanone, 3-pentanone, toluene, p-xylene, ethanol, and mixtures thereof, wherein the solvent is particularly acetone. An advantage of a solvent with a low boiling point or a high vapor pressure is that the process is less energy-intensive and can therefore be carried out more economically.

[0025] The liquid material used in the process may contain or consist of a polymer dissolved in the solvent.

[0026] The polymer can contain or consist of a non-ion-conducting polymer and / or an ion-conducting polymer. For example, the polymer can contain or consist of a fluoropolymer and / or a polyethylene oxide, wherein the fluoropolymer is preferably selected from the group consisting of PVDF-HFP, PVDF, and combinations thereof. The advantage of PVDF-HFP is that it dissolves very well in acetone and forms a network polymer, i.e., a support matrix that provides improved electrolyte distribution and serves as a fixative for a SEI.

[0027] The polymer can be present in the liquid at a concentration of 60 wt.% to 80 wt.%, preferably 65 wt.% to 75 wt.%, particularly 70 wt.%, with respect to the total weight of the liquid.

[0028] The liquid material used in the process may contain or consist of inorganic particles dispersed in the solvent.

[0029] The inorganic particles can be non-electrically conductive inorganic particles, particularly preferably non-electrically conductive ceramic particles.

[0030] The particles can furthermore be ion-conducting inorganic particles, particularly preferably ion-conducting inorganic particles containing or consisting of a sulfide salt, wherein the sulfide salt is particularly selected from the group consisting of lithium phosphorus sulfide (Li₃PS₄), lithium germanium phosphorus sulfide (Li₁₀GeP₂S₁₂), lithium silicon phosphorus sulfide (Li₁₁Si₂PS₁₂), Li₆PS₅Cl, Li₆PS₅Br, and combinations thereof. The advantage of sulfide salts is that a high ionic conductivity, competitive with that of commercially available liquid electrolytes, is achieved.

[0031] In this process, the solvent can be evaporated from the liquid at a temperature in the range of 20 to 30 °C, preferably at 25 °C. This is particularly energy-efficient, as evaporation can take place at ambient temperature and no additional heat energy needs to be supplied for the evaporation process.

[0032] The method can further comprise, after step d), the application of a liquid electrolyte for a galvanic cell to the second surface of the separator membrane, wherein the liquid electrolyte penetrates via capillary forces at least into a part of the pores of the separator membrane, into the space between the surface of the planar electrode and the first surface of the separator membrane and into the pores of the surface of the planar electrode, wherein the liquid electrolyte in particular contacts the surface of the planar electrode and the first surface of the separator membrane.

[0033] The liquid electrolyte used for this purpose can contain a liquid selected from the group consisting of EC, PC, DMC, EMC, DEC, VEC, VC, FEC, TBAC (acetyl tributyl citrate), GTB (glyceryl trityrate), GTA (glyceryl triacetate), γ-buthyrolactone, and combinations thereof, wherein the liquid is preferably selected from the group consisting of PC, FEC, EC, VEC, TBAC, GTB, GTA, and combinations thereof. The advantage of PC, FEC, EC, VEC, TBAC, GTB, and GTA lies in their high boiling point and temperature resistance, which reduces the risk of fire and increases operational safety.

[0034] Furthermore, the liquid electrolyte used for this purpose can contain a lithium conducting salt, wherein the lithium conducting salt is preferably selected from the group consisting of LiPF 6 , LiClO 4 , LiNO 3 , C 6 H 18 LiNSi 2 , F 2 LiNO 4 S 2 , C 2 F 6 LiNO 4 S 2 , LiB[C 2 O 4 ] 2 , LiBF 4 and combinations thereof.

[0035] Apart from this, the liquid electrolyte used for this purpose may contain a sodium conducting salt, wherein the sodium conducting salt is preferably selected from the group consisting of NaPF 6 , NaBF 4 , NaTF, NaTFSI, NaClO 4 and combinations thereof.

[0036] Furthermore, according to the invention, an electrode for a galvanic cell is provided, containing or consisting of a) a planar electrode, wherein the planar electrode has a surface; b) a separator membrane having a first surface, a second surface opposite the first surface, and pores, wherein the first surface of the separator membrane is applied to the surface of the planar electrode, and there is a space between the surface of the planar electrode and the first surface of the separator membrane;and c) at least one material selected from the group consisting of polymer, inorganic particles, organic particles and combinations thereof, wherein the material is arranged at least in a part of the pores of the separator membrane, in the space between the surface of the planar electrode and the first surface of the separator membrane and in pores of the surface of the planar electrode, and wherein the material makes planar contact with the first surface of the separator membrane and the surface of the planar electrode.

[0037] The electrode according to the invention exhibits a high energy density at the cell level as well as high chemical, electrochemical and mechanical stability.

[0038] Consequently, the electrode according to the invention exhibits high cycle stability and enables high operating currents.

[0039] The planar electrode can contain or consist of an alkali metal, optionally coated with a metal selected from the group consisting of stainless steel, nickel, copper, indium, aluminum, and combinations thereof. The alkali metal is preferably selected from the group consisting of lithium, sodium, and combinations thereof. The advantage of lithium is its high specific capacity of > 3000 Ah / kg (10 times that of commercial graphite anodes), its low anode potential of 0 V vs. Li / Li+, and its very high energy density.

[0040] Furthermore, the planar electrode can contain or consist of carbon, preferably a carbon selected from the group consisting of graphite, graphene and combinations thereof.

[0041] Furthermore, the planar electrode can contain or consist of silicon, a silicon alloy and / or a silicon composite.

[0042] Apart from that, the planar electrode can contain or consist of a metal selected from the group consisting of stainless steel, nickel, copper, indium, and aluminum, preferably aluminum. One advantage of aluminum is that it is less expensive than other suitable alloying elements such as indium or silicon. Further advantages of aluminum lie in its low anode potential U, which is approximately 0.3 V for a LiAl alloy vs. Li / Li (comparable to graphite). Furthermore, aluminum can provide a high specific capacitance C (C of a LiAl is approximately 993 Ah / kg, which is about three times that of graphite). In addition, the available energy density E = C * U is very high in the case of aluminum. The aluminum can be alloyed, preferably with at least one element selected from group II, group III, or group IV of the periodic table.Main group of the periodic table, a subgroup of the periodic table and combinations thereof, wherein the at least one element is preferably selected from the group consisting of magnesium, indium, zinc, tin, silicon, manganese and combinations thereof.

[0043] Furthermore, the planar electrode may contain or consist of a cathode material preferably selected from the group consisting of nickel-manganese-cobalt oxide, lithium iron phosphate, lithium manganese oxide, lithium-nickel-manganese oxide, lithium nickel oxide, lithium cobalt oxide, lithium aluminum nickel oxide, lithium manganese phosphate, lithium iron manganese phosphate and combinations thereof.

[0044] The planar electrode can have a thickness, in a direction perpendicular to the surface of the planar electrode, in the range of 5 to 100 µm, preferably 10 to 50 µm, particularly preferably 20 to 40 µm.

[0045] Furthermore, the planar electrode can have a surface texture on its surface. The surface texture preferably has a structure depth in the range of 1 nm to 100 µm, wherein the surface texture is particularly preferably selected from the group consisting of embossed surface texture, brushed surface texture, grooved surface texture, patterned surface texture, and combinations thereof.

[0046] The separator membrane can consist of at least one layer, optionally at least one further layer (i.e., at least two layers).

[0047] The at least one layer, optionally also the at least one further layer, can contain or consist of an electrically insulating material, wherein the material preferably has a specific electrical resistance of ≥ 10 10< Ω·mm 2< / m, particularly preferably ≥ 10 11< Ω·mm 2< / m.

[0048] Furthermore, the at least one layer, and optionally the at least one further layer, can contain or consist of an organic material, preferably a polymeric plastic. The polymeric plastic is particularly preferably selected from the group consisting of polyolefin, fluoropolymer, polyamide, polyimide and combinations thereof, wherein the polymeric plastic is particularly selected from the group consisting of polyethylene, polypropylene, polytetrafluoroethylene, polyamide, para-aramid, polyimide and combinations thereof.

[0049] Furthermore, the at least one layer, and optionally the at least one further layer, can contain or consist of an inorganic material, preferably a ceramic material, wherein the ceramic material is selected in particular from the group consisting of oxide ceramics, carbide ceramics, nitride ceramics, and phosphate ceramics. The oxide ceramic can be aluminum oxide (Al₂O₃). Al₂O₃ has the advantage of being cost-effective compared to solid electrolyte salts such as lithium phosphorus sulfide. Furthermore, Al₂O₃ forms an inert protective layer and thus prevents undesirable side reactions. In addition, Al₂O₃ (in particle form) provides a porous structure, which improves electrolyte distribution and creates a SEI precursor effect.

[0050] Furthermore, at least one layer, and optionally at least one additional layer, can contain or consist of an ion-conducting material.

[0051] The at least one layer, optionally also the at least one further layer, can have a thickness, in a direction perpendicular to the surface of the planar electrode, in the range of 1 µm to 300 µm, preferably in the range of 1 µm to 100 µm.

[0052] Furthermore, the at least one layer, optionally also the at least one further layer, can have a porosity in the range of 30% to 70%, preferably in the range of 40% to 60%, particularly preferably in the range of 45% to 50%.

[0053] The material, which is arranged in at least part of the pores of the separator membrane, in the space between the surface of the planar electrode and the first surface of the separator membrane, and in the pores of the surface of the planar electrode, may contain or consist of a polymer.

[0054] The polymer can contain or consist of a non-ion-conducting polymer and / or an ion-conducting polymer. For example, the polymer can contain or consist of a fluoropolymer and / or a polyethylene oxide, wherein the fluoropolymer is preferably selected from the group consisting of PVDF-HFP, PVDF, and combinations thereof. The advantage of PVDF-HFP is that it dissolves very well in acetone and forms a network polymer, i.e., a support matrix that provides improved electrolyte distribution and serves as a fixative for a SEI.

[0055] The material, which is arranged in at least part of the pores of the separator membrane, in the space between the surface of the planar electrode and the first surface of the separator membrane, and in the pores of the surface of the planar electrode, may contain or consist of inorganic particles.

[0056] The inorganic particles can be non-electrically conductive inorganic particles, particularly preferably non-electrically conductive ceramic particles.

[0057] Furthermore, the inorganic particles can be ion-conducting inorganic particles, particularly preferably ion-conducting inorganic particles containing or consisting of a sulfide salt, wherein the sulfide salt is selected in particular from the group consisting of lithium phosphorus sulfide (Li₃PS₄), lithium germanium phosphorus sulfide (Li₁₀GeP₂S₁₂), lithium silicon phosphorus sulfide (Li₁₁Si₂PS₁₂), Li₆PS₅Cl, Li₆PS₅Br, and combinations thereof. The advantage of sulfide salts is that a high ionic conductivity, competitive with that of commercially available liquid electrolytes, is achieved.

[0058] The electrode can contain a liquid electrolyte at least in part of the pores of the separator membrane, in the space between the surface of the planar electrode and the first surface of the separator membrane, and in the pores of the surface of the planar electrode, wherein the liquid electrolyte in particular contacts the surface of the planar electrode and the first surface of the separator membrane.

[0059] The liquid electrolyte may contain a liquid selected from the group consisting of EC, PC, DMC, EMC, DEC, VEC, VC, FEC, TBAC (acetyl tributyl citrate), GTB (glyceryl triethylate), GTA (glyceryl triacetate), γ-buthyrolactone, and combinations thereof, wherein the liquid is preferably selected from the group consisting of PC, FEC, EC, VEC, TBAC, GTB, GTA, and combinations thereof. The advantage of PC, FEC, EC, VEC, TBAC, GTB, and GTA lies in their high boiling point and temperature resistance, which reduces the risk of fire and increases operational safety.

[0060] Furthermore, the liquid electrolyte can contain a lithium conducting salt, wherein the lithium conducting salt is preferably selected from the group consisting of LiPF 6 , LiClO 4 , LiNO 3 , C 6 H 18 LiNSi 2 , F 2 LiNO 4 S 2 , C 2 F 6 LiNO 4 S 2 , LiB[C 2 O 4 ] 2 , LiBF 4 and combinations thereof.

[0061] Apart from that, the liquid electrolyte may contain a sodium conducting salt, wherein the sodium conducting salt is preferably selected from the group consisting of NaPF 6 , NaBF 4 , NaTF, NaTFSI, NaClO 4 and combinations thereof.

[0062] The electrode according to the invention can be produced using the method according to the invention.

[0063] According to the invention, a galvanic cell is also provided, comprising an electrode according to the invention, a counter electrode and an electrolyte.

[0064] The use of the galvanic cell according to the invention for the energy supply of i) a mobile device, preferably a mobile phone, a vehicle, an aircraft and / or a ship; and / or ii) a stationary device, preferably a building, is proposed.

[0065] The following figure and example will be used to explain the subject matter of the invention in more detail, without limiting it to the specific embodiments shown here.

[0066] The figure schematically shows an electrode according to the invention, its production, and its treatment with a liquid electrolyte. A planar electrode 4 is provided, and a separator membrane 2 is arranged on its surface. A liquid 1, containing or consisting of a polymer (e.g., PVDF-HFP) dissolved in an organic solvent (e.g., acetone), is applied to the separator membrane 2, causing the liquid to penetrate the pores of the separator membrane 2, the space between the separator membrane 2 and the planar electrode 4, and the pores of the surface of the planar electrode 4. The liquid evaporates, leaving the material in the pores of the separator membrane 2, in the space between the separator membrane and the planar electrode 4, and in the pores of the surface of the planar electrode 4, thus forming an enriched material layer 3.In a further step 5, a liquid electrolyte 6 is then applied to the separator membrane 2, creating a composite 9 consisting of a separator membrane 7 impregnated with liquid electrolyte and a material layer 8 impregnated with liquid electrolyte 6. The material located in the pores of the separator membrane 7, in the material layer 8, and in the pores of the surface of the planar electrode 4 may have swollen due to the liquid electrolyte. Example - Manufacturing an electrode for a galvanic cell

[0067] A polyolefin membrane is applied to a current collector foil. A liquid containing an organic solvent and a dissolved polymer is prepared. This liquid is pipetted onto the polyolefin membrane, allowing it to penetrate to the interface between the current collector and the polyolefin membrane (the space between the membrane and the current collector foil). The organic solvent is then evaporated, causing the polymer, now located in the pores of the polyolefin membrane, in the space between the polyolefin membrane and the current collector foil, and in the pores on the surface of the current collector foil, to harden.

[0068] A liquid electrolyte can now be applied to the polyolefin membrane, allowing the liquid electrolyte to penetrate into the areas where the polymer is located. The polymer can then swell (or gel) due to the liquid electrolyte. This step can also occur when the electrode is used in a galvanic cell. Reference symbol list

[0069] 1: Liquid containing material, for example, an organic solvent (e.g., acetone) with a dissolved polymer (e.g., PVDF-HFP); 2: Separator membrane (without liquid electrolyte); 3: Enriched material layer formed from the enrichment of material (e.g., polymer) in the pores of the separator membrane, the space between the membranes, and the pores of the planar electrode after evaporation of the organic solvent (e.g., acetone); 4: Planar electrode (e.g., aluminum foil); 5: Step of applying liquid electrolyte; 6: Liquid electrolyte; 7: Separator membrane saturated with liquid electrolyte; 8: Enriched material layer saturated with liquid electrolyte; and 9: Composite of separator membrane saturated with liquid electrolyte and material layer saturated with liquid electrolyte.

Claims

1. A method for producing an electrode for a galvanic cell, comprising the steps of a) providing a areal electrode, wherein the areal electrode has a surface; b) applying a first surface of a separator membrane to the surface of the areal electrode so that an intermediate space is formed between the surface of the areal electrode and the first surface of the separator membrane; c) applying a liquid to a second surface of the separator membrane opposite the first surface, wherein the liquid comprises a solvent and a material selected from the group consisting of polymer, inorganic particles, organic particles and combinations thereof, wherein the liquid comprising its solvent and its material penetrates, by way of capillary forces, at least into the pores of the separator membrane, into the intermediate space between the surface of the areal electrode and the first surface of the separator membrane, and into pores of the surface of the areal electrode; and d) evaporating the solvent of the liquid, wherein an electrode is created, which comprises the material of the liquid in the intermediate space between the surface of the electrode and the first surface of the separator membrane and in at least a proportion of the pores, wherein the material contacts the surface of the electrode and the first surface of the separator membrane extensively.

2. The method according to the preceding claim, characterized in that the areal electrode i) comprises or consists of an alkali metal, optionally coated on a metal selected from the group consisting of stainless steel, nickel, copper, indium, aluminium and combinations thereof, wherein the alkali metal is preferably selected from the group consisting of lithium, sodium and combinations thereof; and / or ii) comprises or consists of carbon, preferably a carbon selected from the group consisting of graphite, graphene and combinations thereof; and / or iii) comprises or consists of silicon, a silicon alloy and / or a silicon composite; and / or iv) comprises or consists of a metal selected from the group consisting of stainless steel, nickel, copper, indium, aluminium, preferably aluminium, wherein the aluminium is optionally alloyed, preferably with at least one element selected from the II. main group of the periodic table, the III. main group of the periodic table, the IV. main group of the periodic table, a subgroup of the periodic table and combinations thereof, wherein the at least one element is preferably selected from the group consisting of magnesium, indium, zinc, tin, silicon, manganese and combinations thereof; and / or v) comprises or consists of a cathode material, which is preferably selected from the group consisting of nickel manganese cobalt oxide, lithium iron phosphate, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel oxide, lithium cobalt oxide, lithium aluminum nickel oxide, lithium manganese phosphate, lithium iron manganese phosphate, and combinations thereof; and / or vi) has a thickness, in a direction perpendicular to the surface of the areal electrode, in the range from 5 to 100 µm, preferably 10 to 50 µm, particularly preferably 20 to 40 µm; and / or vii) has a surface structuring on its surface, wherein the surface structuring preferably has a structure depth in the range from 1 nm to 100 µm, wherein the surface structuring is particularly preferably selected from the group consisting of embossed surface structuring, brushed surface structuring, patterned surface structuring, corrugated surface structuring and combinations thereof.

3. The method according to any one of the preceding claims, characterized in that the separator membrane consists of at least one layer, optionally also at least one further layer, wherein the at least one layer, optionally also the at least one further layer i) comprises or consists of an electrically insulating material, wherein the material preferably has a specific electrical resistance of ≥ 1010 Ω·mm2 / m, particularly preferably ≥ 1011 Ω·mm2 / m; and / or ii) comprises or consists of an organic material, preferably comprises or consists of a polymeric plastic, wherein the polymeric plastic is particularly preferably selected from the group consisting of polyolefin, fluoropolymer, polyamide, polyimide and combinations thereof, wherein the polymeric plastic is in particular selected from the group consisting of polyethylene, polypropylene, polytetrafluoroethylene, polyamide, para-aramide, polyimide and combinations thereof; and / or iii) comprises or consists of an inorganic material, preferably comprises or consists of a ceramic material, wherein the ceramic material is selected in particular from the group consisting of oxide ceramics, carbide ceramics, nitride ceramics and phosphate ceramics; and / or iv) has a thickness, in a direction perpendicular to the surface of the areal electrode, in the range from 1 µm to 300 µm, preferably in the range from 1 µm to 100 µm; and / or v) has a porosity in the range of from 30% to 70%, preferably in the range from 40% to 60%, particularly preferably in the range from 45% to 50%.

4. The method according to any one of the preceding claims, characterized in that the liquid comprises a solvent which has a boiling point at atmospheric pressure of ≤ 156°C, preferably ≤ 80°C, particularly preferably ≤ 56°C, and / or has a vapour pressure at 20°C of ≥ 3 hPa, preferably ≥ 58 hPa, particularly preferably ≥ 246 hPa, wherein the solvent is optionally selected from the group consisting of acetone, DEC, DMAC, 3-hexanone, THF, butanone, 3-pentanone, toluene, p-xylene, ethanol and mixtures thereof, wherein the solvent is particularly acetone.

5. The method according to any one of the preceding claims, characterized in that the material of the liquid comprises or consists of a polymer dissolved in the solvent, wherein the polymer preferably i) comprises or consists of a non-ion-conducting polymer and / or an ion-conducting polymer; and / or ii) comprises or consists of a fluoropolymer and / or a polyethylene oxide, wherein the fluoropolymer is preferably selected from the group consisting of PVDF-HFP, PVDF and combinations thereof; and / or iii) is present in the liquid in a concentration from 60 wt.% to 80 wt.%, preferably 65 wt.% to 75 wt., in particular 70 wt.%, in relation to the total weight of the liquid.

6. The method according to any one of the preceding claims, characterized in that the material of the liquid comprises or consists of inorganic particles which are dispersed in the solvent, wherein the inorganic particles preferably i) are non-electrically conductive inorganic particles, particularly preferably non-electrically conductive ceramic particles; and / or ii) are ion-conducting inorganic particles, particularly preferably ion-conducting inorganic particles comprising or consisting of a sulfidic salt, wherein the sulfidic salt is particularly selected from the group consisting of lithium phosphorus sulfide, lithium germanium phosphorus sulfide, lithium silicon phosphorus sulfide, Li6PS5Cl, Li6PS5Br and combinations thereof.

7. The method according to any one of the preceding claims, characterized in that the method further comprises after step d): applying a liquid electrolyte for a galvanic cell to the second surface of the separator membrane, wherein the liquid electrolyte penetrates, by way of capillary forces, at least in a proportion of the pores of the separator membrane, into the intermediate space between the surface of the areal electrode and the first surface of the separator membrane, and into the pores of the surface of the areal electrode, wherein the liquid electrolyte contacts in particular the surface of the areal electrode and the first surface of the separator membrane.

8. An electrode for a galvanic cell, comprising or consisting of a) a areal electrode, wherein the areal electrode has a surface; b) a separator membrane having a first surface, a second surface opposite the first surface, and pores, wherein the first surface of the separator membrane is applied to the surface of the areal electrode, and there is an intermediate space between the surface of the areal electrode and the first surface of the separator membrane; c) a material selected from the group consisting of polymer, inorganic particles, organic particles, and combinations thereof, wherein the material is arranged in at least a proportion of the pores of the separator membrane, is arranged in the intermediate space between the surface of the areal electrode and the first surface of the separator membrane, and is arranged in pores of the surface of the areal electrode, and wherein the material contacts the first surface of the separator membrane and the surface of the areal electrode extensively.

9. The electrode according to claim 8, characterized in that the areal electrode i) comprises or consists of an alkali metal, optionally coated on a metal selected from the group consisting of stainless steel, nickel, copper, indium, aluminium and combinations thereof, wherein the alkali metal is preferably selected from the group consisting of lithium, sodium and combinations thereof; and / or ii) comprises or consists of carbon, preferably a carbon selected from the group consisting of graphite, graphene and combinations thereof; and / or iii) comprises or consists of silicon, a silicon alloy and / or a silicon composite; and / or iv) comprises or consists of a metal selected from the group consisting of stainless steel, nickel, copper, indium, aluminium, preferably aluminium, wherein the aluminium is optionally alloyed, preferably with at least one element selected from the II. main group of the periodic table, the III. main group of the periodic table, the IV. main group of the periodic table, a subgroup of the periodic table and combinations thereof, wherein the at least one element is preferably selected from the group consisting of magnesium, indium, zinc, tin, silicon, manganese and combinations thereof; and / or v) comprises or consists of a cathode material, which is preferably selected from the group consisting of nickel manganese cobalt oxide, lithium iron phosphate, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel oxide, lithium cobalt oxide, lithium aluminum nickel oxide, lithium manganese phosphate, lithium iron manganese phosphate, and combinations thereof; and / or vi) has a thickness, in a direction perpendicular to the surface of the areal electrode, in the range from 5 to 100 µm, preferably 10 to 50 µm, particularly preferably 20 to 40 µm; and / or vii) has a surface structuring on the surface of the areal electrode, wherein the surface structuring preferably has a structure depth in the range from 1 nm to 100 µm, wherein the surface structuring is particularly preferably selected from the group consisting of embossed surface structuring, brushed surface structuring, corrugated surface structuring, patterned surface structuring and combinations thereof.

10. The electrode according to any one of claims 8 or 9, characterized in that the separator membrane consists of at least one layer, optionally also at least one further layer, wherein the at least one layer, optionally also the at least one further layer, i) comprises or consists of an electrically insulating material, wherein the material preferably has a specific electrical resistance of ≥ 1010 Ω·mm2 / m, particularly preferably ≥ 1011 Ω·mm2 / m; and / or ii) comprises or consists of an organic material, preferably comprises or consists of a polymeric plastic, wherein the polymeric plastic is particularly preferably selected from the group consisting of polyolefin, fluoropolymer, polyamide, polyimide and combinations thereof, wherein the polymeric plastic is in particular selected from the group consisting of polyethylene, polypropylene, polytetrafluoroethylene, polyamide, para-aramide, polyimide and combinations thereof; and / or iii) comprises or consists of an inorganic material, preferably comprises or consists of a ceramic material, wherein the ceramic material is selected in particular from the group consisting of oxide ceramics, carbide ceramics, nitride ceramics and phosphate ceramics; and / or iv) has a thickness, in a direction perpendicular to the surface of the areal electrode, in the range from 1 µm to 300 µm, preferably in the range from 1 µm to 100 µm; and / or v) has a porosity in the range of from 30% to 70%, preferably in the range from 40% to 60%, particularly preferably in the range from 45% to 50%.

11. The electrode according to any one of claims 8 to 10, characterized in that the material, which is arranged in at least a proportion of the pores of the separator membrane, is arranged in the intermediate space between the surface of the areal electrode and the first surface of the separator membrane and is arranged in the pores of the surface of the areal electrode, comprises or consists of a polymer, wherein the polymer preferably i) comprises or consists of a non-ion-conducting polymer and / or an ion-conducting polymer; and / or ii) comprises or consists of a fluoropolymer and / or a polyethylene oxide, wherein the fluoropolymer is preferably selected from the group consisting of PVDF-HFP, PVDF and combinations thereof.

12. The electrode according to any one of claims 8 to 11, characterized in that the material, which is arranged in at least a proportion of the pores of the separator membrane, is arranged in the intermediate space between the surface of the areal electrode and the first surface of the separator membrane and is arranged in the pores of the surface of the areal electrode, comprises or consists of inorganic particles, wherein the inorganic particles preferably i) are non-electrically conductive inorganic particles, particularly preferably non-electrically conductive ceramic particles; and / or ii) are ion-conducting inorganic particles, particularly preferably ion-conducting inorganic particles comprising or consisting of a sulfidic salt, wherein the sulfidic salt is particularly selected from the group consisting of lithium phosphorus sulfide, lithium germanium phosphorus sulfide, lithium silicon phosphorus sulfide, Li6PS5Cl, Li6PS5Br and combinations thereof.

13. The electrode according to any one of claims 8 to 12, characterized in that a liquid electrolyte is arranged at least in a proportion of the pores of the separator membrane, in the intermediate space between the surface of the areal electrode and the first surface of the separator membrane and in the pores of the surface of the areal electrode, wherein the liquid electrolyte contacts in particular the surface of the areal electrode and the first surface of the separator membrane.

14. A galvanic cell comprising an electrode according to any one of claims 8 to 13, a counter electrode and an electrolyte.

15. Use of the galvanic cell according to claim 14 for power supply i) of a mobile device, preferably a mobile phone, a vehicle, an aircraft and / or a ship; and / or ii) of a stationary device, preferably a building.