Electrochemical sodium metal halide secondary cell, battery module and systems comprising these

Abstract

The invention relates to an electrochemical sodium metal halide secondary cell (0) comprising a housing (1) and a current collector that is resistant to long-term mechanical and / or chemical stresses and alternating thermal loads, with a cavity (14) containing a reservoir for receiving the secondary electrolyte, as well as a battery module, system comprising the battery module, as well as an energy storage system and its use.

Description

[0001] The invention relates to an electrochemical sodium metal halide secondary cell comprising a housing and a current collector that is mechanically and / or chemically resistant and able to withstand fluctuating thermal loads over the long term, with a cavity containing a reservoir for receiving the secondary electrolyte, as well as a battery module, system comprising the battery module, a battery kit, an energy storage system, and its use. The sodium metal halide secondary cell according to the invention is preferably used as a sodium metal halide cell, in particular as a sodium nickel chloride cell, in demanding stationary applications and / or high-performance batteries.

[0002] The aforementioned electrochemical cells contain an anode, consisting of at least one metal in the charged state, and a cathode, usually in porous form, consisting of at least one transition metal and at least one metal halide (e.g., of the metals sodium, nickel, iron, aluminum, and / or copper), which is impregnated with a molten salt, at least in the operating state, for ion conduction, and a metallic current collector for electrical contacting the cathode. The molten salt is considered here to be the matrix in which the cathode, in particular the porous cathode, is embedded in the cathode compartment. Depending on the operating temperature, the matrix is ​​solid or exists as a liquid molten salt, in particular as a sodium aluminum chloride molten salt. Preferably, the matrix penetrates into intragranular and intergranular cavities or interparticle and intraparticle pores.

[0003] It is known from the prior art of accumulators and secondary batteries that electrochemical cells based on sodium metal halide chemistry are used, particularly for high-performance batteries in electric vehicles and demanding stationary applications, because they exhibit high specific power and energy densities and a long cycle life. These are thermal batteries in which the anode is formed by a thermally liquefied alkali metal, in this case sodium, and the cathode by a liquid salt melt that impregnates a porous material made of metals and metal halides, e.g., nickel chloride and sodium chloride. The two electrodes are separated by an electrically insulating separator that acts as a solid electrolyte, e.g., sodium β-aluminate (sodium beta-aluminate) with the largest possible β'' phase, which conducts sodium ions very well above 270°C, i.e., is permeable to sodium ions.

[0004] Such batteries do not exhibit electrochemical self-discharge and have an energy efficiency of approximately 90% and a coulomb efficiency of 100%.

[0005] US2014 / 0295237A1 discloses a current collector consisting of a grid with grid openings or mesh sizes of 2 to 4 mm, made of a wire mesh of 0.1 to 1 mm. A disadvantage of this current collector is the reduced durability of the grid due to potential charges up to 100% SoC or overcharging of the cell over a long period, which can become problematic depending on the thickness of the wire mesh. Furthermore, such a current collector exhibits varying current densities at the grid due to different geometries of the grid, particularly at the contact points of the overlapping wires that form the grid mesh. The grid electrode is designed such that cathode material and secondary electrolyte are present both inside and outside the grid after filling. The cathode grid has through-holes (258) extending into the cathode. The grid is also open at the bottom.Furthermore, the mesh size of the grid is specified as 2 to 4 mm. The geometry of the grid disrupts the ion flow. There is no cathode in the normally most efficient area of ​​the cathode compartment (small distance to the solid electrolyte). No reservoir for NaAlCl4 is provided to ensure complete cathode wetting during cell charging and the associated volume reduction.

[0006] From GB 2,281,436 B, filed in 1994, it is known to add aluminum, in particular up to 1 wt%, to an electrode to create porosity in the cathode, as it forms sodium tetrachloroaluminate [NaAlCl4] and thus promotes full charging on the first charge. Furthermore, a small amount of sodium is generated to wet the anode side of the solid electrolyte separator, and a certain amount of over-discharge capacity is also provided. From EP 2306580 A1, the use of metallic aluminum in the cathode composition is also known from comparative tests.

[0007] US Patent 2015 / 0004456 A1 describes a current collector for a sodium metal halide cell in which a lamellar design of the current collector is intended to enable high performance and cost savings of the electrochemical cells. The current collector has at least one flat, elongated fin made of electrically conductive material, is curved with respect to its dominant longitudinal axis, and is welded or soldered at its curved upper end to a flat metal ring. This ring allows the current collector to be attached to the cell lid with the fin(s) precisely centered on the cell axis. In a preferred embodiment, two complementarily slotted lamellae with a center section open for a carbon felt are arranged in a crossed configuration.However, a disadvantage of all the different designs of the current collector is twofold: firstly, the lamellae must be bonded to the metal ring in a material-bonded and precisely aligned manner; and secondly, a carbon felt of considerable dimensions must be positioned between the metal plates to store the molten salt, and this felt is only partially fixed in place. Since the carbon felt itself occupies space, the electrical storage capacity of the sodium / metal chloride cell is reduced. Furthermore, an imprecisely positioned carbon felt results in locally varying current densities due to differing thicknesses of the cathode sections, and thus the cell properties can vary from cell to cell.

[0008] DE10 2019 135 752 A1 relates to an electrochemical sodium metal halide cell with a current collector with elements for increasing the surface area.

[0009] The invention was based on the objective of providing an improved current collector, synonymous with a current collector, that delivers very homogeneous current densities while simultaneously reducing the amount of carbon felt required. A further objective was to provide a current collector for a separator, in particular a cylindrical tubular separator, that delivers very homogeneous current densities while also addressing the situation where the volume of the cathode, especially the cathode granules, decreases during charging of the secondary cell. To ensure a high current density, it is necessary, and therefore also an objective, to compensate for this decreasing volume, which in the prior art is compensated for by using carbon felt impregnated with secondary electrolyte, with an improved technical solution.Furthermore, the invention aimed to provide a solution in which the cathode, in particular the cathode granules, is preferably completely and permanently surrounded by a matrix comprising sodium metal halide, and in particular, reservoir(s) for sodium metal halide can be provided. Therefore, the invention also aimed to achieve volume equalization through the secondary electrolyte in a substantially different way. Furthermore, the invention aimed to minimize the free path that the electrons must travel from the separator while simultaneously ensuring a very homogeneous result. Finally, the invention aimed to provide a current collector and / or separator, each exhibiting high cycle stability both chemically and mechanically, thus advantageously providing a very low-maintenance secondary cell.Furthermore, the task was to provide a secondary cell that could be filled in an automated process with reduced time expenditure. Additionally, the current collector should achieve the largest possible surface-to-cross-sectional area ratio, with its alignment along the axis of symmetry of the electrochemical cell to ensure a uniform current density distribution in the electrode. This alignment should facilitate the current collector's design, its simple fixation in manufacturing, and the simplified assembly of the sodium metal halide electrochemical cell for filling with electrode components. Finally, the task involved developing a battery module, a system comprising battery modules, a battery kit, and an energy storage system based on such a current collector and the corresponding secondary cell.

[0010] Surprisingly, the tasks could be solved with an electrochemical sodium metal halide secondary cell according to claim 1, a battery module according to claim 16, a system according to claim 19, and a battery kit for energy storage with an energy storage capacity according to claim 20, in particular of greater than or equal to 60 kWh, in particular of greater than or equal to 100 kWh up to 500 kWh, as well as a battery, in particular with an energy storage capacity of greater than or equal to 550 kWh up to less than or equal to 10 MWh, in particular of greater than or equal to 1 MWh up to less than or equal to 4 MWh, as well as an energy storage system according to claim 24 and the use according to claim 25.

[0011] Surprisingly, the problems of the invention were solved by enabling intermediate storage of the secondary electrolyte in the current collector according to claim 1, without the cathode, in particular cathode granules, entering the interior of the current collector in one variant. In a preferred embodiment, the geometric design of the current collector allows for an identical distance to the current collector to be set along the entire cylindrical height of the separator, while simultaneously optimizing and reducing the distance between the current collector and the separator. In alternative preferred embodiments, the separator can be configured at a variable distance from the current collector.

[0012] According to the invention, the current collector can be easily and automatically filled with cathode granules without the granules entering inactive areas of the secondary cell. Furthermore, the current collector itself can be used as an intermediate storage medium for the secondary electrolyte, while simultaneously reducing the amount of carbon felt required. In this way, the amount of cathode material could be further optimized with respect to the achievable current density. In a preferred embodiment of the current collector, only one carbon felt plug is required to close the cavity, particularly at the lower end of the current collector cavity, in order to prevent the ingress of cathode material, especially cathode granules.The carbon felt according to the invention is used as a substrate, filter, or membrane and has a volume over 95% smaller than that of a carbon felt required to store an analogous amount of sodium metal halide. The carbon felt is thus primarily used as a barrier and less frequently, if at all, as an intermediate storage medium. Alternatively, the lower end of the current collector can be sealed with an inert membrane, such as a perforated film or mesh, in particular a perforated metal foil and / or metallic mesh, to prevent the ingress of the cathode, preferably allowing secondary electrolyte to penetrate the cavity of the current collector. Likewise, the lower end of the current collector can be partially or completely welded shut or sealed with a cover, whereby it may be necessary to ensure that the secondary electrolyte can penetrate the inner cavity in the region of the cathode in order to utilize the cavity as a reservoir.

[0013] Micro-CT scans (micro-computed tomography for component analysis) demonstrate that, with the electrode according to the invention, the NaAlCl4 fill level within the NaAlCl4 matrix decreases in the cold state before initialization and at 100% SoC (State of Charge, i.e., the charge level of the secondary cell). This decrease occurs because the NaAlCl4 is absorbed by the porous cathode and surrounds it as a matrix. However, the cathode remains completely surrounded by the NaAlCl4 matrix. "Surrounded" in this context means that the NaAlCl4 matrix embeds the metal and metal halide powder mixture, particularly the granules, externally and / or internally as a matrix. Thus, NaAlCl4 can be present as a matrix within the intergranular porosity and in the internal pores of the powders and / or granules. Electrochemically, 100% of the theoretical capacity could be achieved, thus demonstrating that the entire cathode was wetted with NaAlCl4.This ensures optimal ion conduction in all charging states of the secondary cell.

[0014] The current collector with a cavity according to the invention allows the surface area of ​​the current collector to be increased while simultaneously reducing material usage compared to a rod-shaped current collector. At the same time, the path to the separator across the cylindrical surface of a preferred current collector remains identical, and a large, flexibly usable reservoir for the secondary electrolyte can be provided in the cavity of the current collector, particularly in an inactive area. Furthermore, it prevents the cathode granules from penetrating an inactive area of ​​the current collector. In this way, the required amount of cathode granules can be further optimized. The secondary electrolyte can penetrate the cavity of the current collector.

[0015] According to the invention, the problem is solved in a preferred alternative by an electrochemical sodium metal halide secondary cell comprising a housing and a separator permeable to sodium ions arranged in the housing; in particular, the secondary cell comprises a housing with a central axis and a separator permeable to sodium ions spaced apart from the central axis of the housing and from the housing. - wherein the separator has a separator wall, in particular an integral separator wall, and a longitudinal central axis, wherein the separator, in particular the separator wall, as a solid primary electrolyte separates an anode compartment of an anode from a cathode compartment of a cathode, and - comprising a cathode that at least partially or completely fills the cathode space, consisting of a mixture of metal powder and / or metal halide powder and / or of granules containing these, as well as - comprising a secondary electrolyte of a sodium metal halide and / or a mixture of sodium metal halides, in particular the secondary electrolyte comprising a mixture of sodium metal halides in the form of a molten salt, preferably as a liquid or as a solidified molten salt, wherein the secondary electrolyte partially or completely fills the cathode space and surrounds, in particular embeds, the mixture, in particular a porous mixture, of the cathode as a matrix, and - a metallic, cathode-side current collector arranged in the cathode space, in particular a metallic cathode-side current collector extending along the longitudinal central axis of the separator, preferably a partially to completely cylindrical current collector, - wherein the current collector has an upper filling area, in particular a cylindrical filling area, with a current collector side wall and inner cavity, and optionally has a contacting area of ​​the cathode-side current collector adjoining the filling area at the top, and - the current collector has a lower area extending into the cathode with a current collector side wall containing a cavity, in particular with a cylindrically shaped area, preferably with a partially to completely cylindrically shaped area with a current collector side wall containing a cavity, in particular an inner cavity, preferably a cylindrical cavity, - and has a defined separation area between the upper filling area and the lower area, in particular a current collector side wall designed as a separation area, wherein the separation area is arranged in particular above the cathode, - wherein the separating area has at least one through-hole, in particular with at least one through-hole in the current collector side wall, preferably with two to four through-holes, and below the separating area with at least one through-hole, in particular with two to more, preferably two to four through-holes, arranged a separating area, - wherein the at least one through-hole connects the inner cavity of the filling area with the cathode space, - optionally, such that the cathode to be filled or filled through the filling area consists of a mixture, in particular a porous mixture, of metal powder and metal halide powder and / or a granulate containing these, at least partially to completely fills the cathode space; preferably, the cathode space is completely filled. - wherein the separation area of ​​the current collector for the cathode, in particular the metal and metal halide powder and / or the granules containing these, is not passable, and, - wherein the current collector in the lower area extending into the cathode is designed with a current collector side wall with a cavity such that the cathode cannot penetrate into the cavity, in particular not as granules and / or powder, and optionally preferably the cavity is accessible to the secondary electrolyte, wherein the cavity in the lower area has a shell which is permeable to the secondary electrolyte and not permeable to the cathode.

[0016] In particular, the cavity for the secondary electrolyte is accessible as a liquid salt melt.

[0017] Preferably, the cavity in the lower region of the current collector side wall, extending into the cathode, is configured such that the cathode cannot penetrate the cavity, particularly not as granules and / or powder, and the cavity is accessible to the secondary electrolyte, or the secondary electrolyte, particularly as a liquid molten salt, can penetrate the cavity. A sodium metal halide secondary cell is defined as a cell comprising as its cathode a cathode material consisting of sodium metal halide and optionally metal. The cathode material may include other conventional metals and / or salts; in particular, it may include the cathode material defined below.

[0018] The invention also relates to a current collector according to the invention. The separating area can comprise a cavity, in particular an inner cavity, which forms a common cavity with the cavity of the filling area.

[0019] It is particularly preferred if the cavity, especially the cavity in the lower region, preferably the secondary electrolyte reservoir, comprises a shell and / or at least partially to completely a substrate, each of which is independently permeable to the secondary electrolyte and impermeable to the cathode, especially the granules and / or powder. Furthermore, or alternatively, the current collector side wall can be formed from a sheet metal shell such that the cavity is accessible to the secondary electrolyte at butt joints or overlapping butt joints. Additionally, the current collector or the shell can be formed in multiple parts. For example, in one alternative, the shell can be formed in multiple parts from formed sheets. In one embodiment, the lower region can be formed as a shell, especially a formed sheet metal shell.The upper section can be formed from a tube and constitute the filling, separating, and dividing area, and optionally the transition area, in particular the first area. Alternatively, the transition area can also be assigned to the second area, comprising the lower area of ​​the current collector. In yet another alternative, the second area comprises only the lower area. In the first case, for example, the filling, separating, and dividing area can be formed from a tube, and the transition area and the lower area, particularly as the second area, can be formed from a sheet metal tube with a transition area and be electrically connected to the dividing area of ​​the first area.Alternatively, the filling, separating, and transition area can be formed from a shaped tube, particularly as the first area, and the lower area, particularly as the second area, can be formed from a sheet metal tube and electrically connected to the transition area of ​​the first area. This electrically conductive connection can be achieved by pressing, bonding, and / or other methods known to those skilled in the art.

[0020] The ratio of the length of the longitudinal center axis or the height of the filling area and the separation area to the length of the longitudinal center axis or the height of the separation area is preferably 10:1 to 1.5:1. The ratio of the length of the longitudinal center axis or the height of the lower area to the length of the longitudinal center axis or the height of a) the separation area or b) the filling, separation, and separation area is preferably 250:1 to 2:1, in particular 100:1 to 5:1, in particular 100:1 to 10:1. The respective ratio of the longitudinal center axes of i) filling area and separation area to ii) separation area and iii) to the lower area is preferably i) : ii) : iii) from 1 : 1 : 5 to 1 : 1 : 100, in particular from 5 : 1 : 5 to 5 : 1 : 75.Furthermore, it is preferred if the ratio of the longitudinal center axis or height of the first area, in particular comprising the transition area, to the second area, in particular comprising the lower area, is from 50 : 1 to 2 : 1, in particular 20 : 1 to 5 : 1, preferably from 10 : 1 to 5 : 1.

[0021] The sheet metal preferably has a thickness of 3 mm or less, in particular 2.5 mm or less, and most preferably 0.3 to 1.5 mm. Furthermore, it is preferred that the current collector side wall, in particular made of a hollow tube, has a wall thickness of 3 mm or less, in particular 0.3 mm or greater, preferably 0.5 to 2.5 mm, and more preferably 0.5 to 1 mm. A side wall thickness of 0.5 to 0.9 mm with a tolerance of ±0.01 mm is further preferred, and a thickness of 0.75 to 0.9 mm with a tolerance of ±0.01 mm is particularly preferred.

[0022] The casing can comprise the current collector side wall, and optionally a bottom part which partially or completely closes a lower opening of the current collector side wall, and / or the casing can comprise the current collector side wall and a substrate, wherein the substrate closes the cavity, in particular a lower opening of the current collector side wall, opposite the cathode but is permeable to the secondary electrolyte.

[0023] In preferred alternatives, i) the current collector side wall can be reshaped in the region of its end so that no cathode can penetrate the cavity, e.g., by pressing the side walls, and / or ii) a lower opening of the current collector side wall can be closed with a bottom part, and / or iii) a lower opening of the current collector side wall can be closed by a substrate serving as a filter or membrane. In all alternatives, it is provided that the secondary electrolyte can penetrate the cavity in the lower region of the cathode, while the cathode itself cannot penetrate the cavity.If the lower opening is closed with a base part, micro-holes may be formed in the base part and / or in the current collector side wall, which allow the secondary electrolyte to penetrate into the cavity and prevent the cathode from penetrating, especially in the areas that are immersed in the secondary electrolyte.

[0024] It is further preferred that the cavity in the lower region of the current collector side wall extending into the cathode, particularly at the lower end of this region, comprises a substrate i) as a filter or membrane and / or a substrate that is permeable to the liquid secondary electrolyte and seals the cavity for the cathode, particularly the granules. Preferably, the substrate seals the lower end of the cavity or the cavity itself against ingress of the cathode and allows ingress of the secondary electrolyte from the sodium metal halide salt melt, and / or the cavity in the lower region of the current collector side wall extending into the cathode is preferably sealed against the cathode by means of a bottom section, particularly as a filter or membrane.

[0025] It is preferred that the cathode comprises a mixture of metal powder and metal halide powder and / or granules containing these, and is particularly preferably composed of these. Particularly preferably, the cathode comprises a mixture of metal powder and metal halide powder as a composition comprising nickel, sodium halide(s), in particular sodium chloride, and optionally sodium fluoride and / or sodium iodide or a mixture of sodium chloride, sodium iodide, and sodium fluoride, and iron(II)S and optionally aluminum. The metal powders may in particular comprise nickel and / or aluminum and / or, as metal halides, alkali metal halides, such preferably sodium halide(s), in particular sodium chloride, and optionally sodium fluoride and / or sodium iodide or a mixture of sodium chloride, sodium iodide, and sodium fluoride. Furthermore, the cathode may comprise other metallic compounds, such as compounds containing sulfur, such as preferably iron(II)S.

[0026] The cathode most preferably consists of a composition selected from nickel, sodium halide(s), in particular sodium chloride, and optionally sodium fluoride and / or sodium iodide or a mixture of sodium chloride, sodium iodide and sodium fluoride, and iron(II)S, and optionally aluminum. Advantageously, the cathode is a granulate comprising this composition, wherein the granulate has a particle size of 400 to 1500 micrometers, in particular 450 to 1400 micrometers. The particle size of the granulate can be determined by sieve analysis.

[0027] The cathode of the secondary cell comprises a substantial excess of nickel as an electrically conductive, metallic network. Theoretically, the secondary cell can be overcharged to 200% SoC. This is ensured by the selected molar nickel-sodium chloride ratio of the cathode. Since the sodium chloride is consumed when charging to 100% SoC, the secondary electrolyte, here NaAlCl₄, decomposes under an applied overcharge voltage, particularly the NaCl-saturated molten salt, which provides further NaCl for the overcharge reaction. This causes the NaAlCl₄ level in the secondary cell to decrease as secondary electrolyte is consumed. Without the reservoir according to the invention, here the lower cavity, the secondary electrolyte level would drop too drastically due to consumption. This can result in the cathode no longer being completely embedded in a matrix of secondary electrolyte.The invention aims to avoid this situation, because if the cathode is not completely embedded in a matrix of secondary electrolyte, ionic conductivity is reduced. The reservoir according to the invention allows for improved ionic conductivity in different operating modes.

[0028] The current collector can be formed from a hollow tube, in particular as a one-piece current collector made of an integral material. Alternatively, the current collector, in particular a multi-part current collector, can be formed from at least one sheet by forming and / or from at least one tube and one sheet by forming. The side edges of the sheet can abut or overlap, with the cavity in particular serving as a secondary electrolyte reservoir, being inaccessible to the cathode but accessible to the secondary electrolyte. The filling area of ​​the current collector has an upper opening, in particular for filling the cathode and / or the secondary electrolyte into the housing of the secondary cell.Alternatively, the cavity is provided in the lower region of the current collector side wall, extending into the cathode. In particular, the cavity is designed as a secondary electrolyte reservoir and is inaccessible to the cathode but accessible to the secondary electrolyte. Specifically, the separation zone of the current collector is not passable for the cathode in the direction of the cavity in the lower region.

[0029] In general, the geometry of the current collector can be optimally adapted to the geometry of the separator, aiming for the most uniform cathode thickness and current density distribution possible. Theoretically, all conceivable geometric shapes are possible; preferably, the current collector and separator are designed as mathematical cylinders whose respective surfaces are parallel to the longitudinal center axis of the current collector and / or separator, and preferably equidistant from each other. A cloverleaf-shaped base is also conceivable. The limiting factors here are the manufacturing of such a solid electrolyte or the sintering process and its structural integrity under pressure.

[0030] In a particularly preferred embodiment, the current collector is formed in multiple parts, in particular comprising a first area, preferably a multi-part or one-piece first area, which includes the filling area, separation area, and cutting area, and optionally a transition area adjoining the cutting area below, and a second area, in particular a multi-part or one-piece second area, comprising the lower area with the current collector side wall and optionally an upper transition area to the cutting area of ​​the first area. The first and second areas, in particular preferably one-piece first area and / or one-piece second area, are electrically conductively connected to each other, in particular by a metallurgical bond.Particularly preferably, these are electrically connected by means of a nickel alloy and / or the first and second regions are coated with a nickel alloy. In a preferred embodiment, the first and second regions are each formed in one piece. Each region can be formed independently from a formed sheet, in particular a sheet formed into a tube, or from a tube. The tube can be further formed to create the respective regions.

[0031] Advantageously, the first section can be formed from a formed sheet metal part, to which the second section, also formed from a formed sheet metal part, is attached. Alternatively, the first and second sections can each be formed independently from a sheet metal part or a tube, wherein a formed sheet metal part can be connected to a tube. It is further preferred that the first section, formed from a sheet metal part, comprises the filling area, separation area, and divider area, and optionally includes the transition area adjoining the divider area below, and that the second section preferably adjoins the divider area below. Preferably, the second section and the transition area are arranged overlapping. Particularly preferred is the first section located within the divider area, especially the transition area, and overlapping the second section. It is also expedient for the first section to be arranged overlapping the outside of the second section.

[0032] Advantageously, all areas of the current collector and the separator wall are independently of one another, preferably coordinated with each other, and each cylindrically designed. It may be advantageous if a section, particularly a cylindrical one, of the current collector side wall extends to the lower end of the current collector side wall.

[0033] The separator, comprising a separator wall and a longitudinal center axis, is preferably formed from an integral separator wall. Particularly preferably, the separator is formed from a rotationally symmetrical separator wall, most preferably from a U-shaped or V-shaped separator wall in the form of a 3D molded body. Advantageously, the separator can also have a polygonal, elliptical, circular, or combination thereof cross-section. Furthermore, the separator can have different cross-sections along its longitudinal center axis. A circular cylindrical shape for the side walls is particularly preferred.

[0034] A preferred electrochemical sodium metal halide secondary cell comprises a housing and a sodium-ion-permeable separator arranged within the housing. It is preferred that the secondary cell has a housing with a central axis and optionally a permeable separator spaced about and from the central axis of the housing. Particularly preferably, the separator is spaced extensively about the central axis of the housing, surrounding and intersecting it, preferably like a rotationally symmetrical U-shaped 3D body. Therefore, the sodium-ion-permeable separator is particularly equidistant from the central axis and / or equidistant from the housing, and especially spaced from both.

[0035] Furthermore, it is preferred if the separator has a longitudinal center axis. The longitudinal center axis of the separator is synonymous with the central axis of the separator. It may also be preferred if the current collector is elongated along the longitudinal center axis, synonymous with the central axis of the separator. The current collector may also have a longitudinal center axis. Preferably, the longitudinal center axes of the housing, the separator, and the current collector coincide.

[0036] The cathode is preferably formed from a porous mixture of metal powder and metal halide powder and / or from a granulate containing these, particularly preferably from a granulate of a mixture of metal powder and metal halide powder.

[0037] The secondary electrolyte is preferably present as a molten salt, more preferably as a liquid and / or solid molten salt and / or in all intermediate states. In particular, the secondary electrolyte forms a matrix that embeds the cathode and preferably partially, and especially preferably completely, surrounds it in all operating modes of the secondary cell, particularly up to 200% SoCc.

[0038] The invention also relates to a current collector in which the lower, cavity-extending region of the current collector side wall of the current collector has an opening at the lower end of the region of the current collector side wall (A), wherein the opening and / or the cavity has a substrate as a filter or membrane in at least one region, wherein the substrate closes the lower end of the cavity or the cavity against penetration of the cathode and allows penetration of the secondary electrolyte from the sodium metal halide salt melt, or (B) has a cover part closing the cavity at the lower end of the region of the current collector side wall, optionally the cover part has at least one microhole, wherein the at least one microhole is dimensioned such that penetration of secondary electrolyte into the cavity is possible and penetration of the cathode is prevented.and / or (C) the pantograph side wall has no openings except for the at least one through-hole in the separating area, and / or the pantograph side wall is formed from a sheet metal part, the edges of which may abut each other, and / or the pantograph side wall has in its lower area i) at least one microhole and / or ii) at least one hole, if the cavity comprises the substrate and covers the at least one hole in the pantograph side wall. The at least one microhole, in particular microholes, preferably has a diameter of less than or equal to 0.4 mm and is in particular arranged at the lower end of the area of ​​the pantograph side wall. The at least one microhole has in particular a diameter of 1 micrometer to 450 micrometers, in particular 100 to 450 micrometers. The opening may be a circular opening, an elliptical opening,The opening can be a polygonal opening or an opening with a perimeter of any area. Optionally, the opening(s) can be formed by reshaping the current collector side wall and / or by metallurgical bonding to a cover part. The opening and / or the cavity can have a substrate as a filter or membrane in at least one region, wherein the substrate seals the lower end of the cavity or the cavity itself against cathode ingress and allows the secondary electrolyte from the sodium metal halide salt melt to enter.

[0039] According to the invention, the problem is solved in a preferred alternative by an electrochemical sodium metal halide secondary cell comprising a housing and a separator permeable to sodium ions arranged in the housing; in particular, the secondary cell comprises a housing with a central axis and a separator permeable to sodium ions extending equidistant to the housing around the central axis of the housing. - wherein the separator comprises a separator wall, in particular an integral separator wall, wherein the separator, in particular the separator wall, as a solid primary electrolyte separates an anode compartment of an anode from a cathode compartment of a cathode, and with - a metallic, cathode-side current collector arranged in the cathode space, in particular a metallic cathode-side current collector extending along the central axis of the separator, in particular an elongated current collector extending along greater than or equal to 50% of the central axis of the separator, in particular a elongated current collector extending along greater than or equal to 80% of the central axis, - wherein the current collector has an upper cylindrical filling area with current collector side wall and inner cavity, in particular a cylindrical cavity, and optionally a contacting area of ​​the cathode-side current collector adjoining the filling area at the top, and the electricity consumer - has a lower cavity extending into the cathode with a cylindrically shaped area with a current collector side wall, in particular a cylindrical cavity, wherein the cavity extends partially to completely to the separation area or optionally to the transition area, and has a formed separation area, in particular the current collector side wall, between the upper filling area and the lower area, wherein the separation area is preferably arranged above the cathode, - wherein the separating area has at least one through-hole, in particular in the pantograph side wall, preferably two to four through-holes, and a separating area arranged below the separating area with at least one through-hole, - wherein at least one through-hole connects the inner cavity of the filling area with the cathode space, optional - so that the cathode to be filled or filled through the filling area, consisting of a mixture, in particular a porous mixture, of metal powder and metal halide powder and / or a granulate containing these, at least partially to completely fills the cathode space, preferably the cathode space is completely filled, - wherein the separation zone for the cathode, in particular the metal and metal halide powder and / or the granules containing these, is not passable.

[0040] The lower area extending into the cathode, having a cavity, in particular as a secondary electrolyte reservoir, preferably cylindrically shaped area of ​​the current collector side wall of the current collector, can be located at the lower end of the cylindrically shaped area of ​​the current collector side wall. (A) have an opening, in particular a circular opening, elliptical opening, polygonal opening or an opening with a perimeter of any area, optionally wherein the opening(s) may be obtained by reshaping the current collector side wall and / or by metallurgical bonding with a cover part. Alternatively or additionally, the opening and / or the cavity may have a substrate as a filter or membrane in at least one region, wherein the substrate seals the lower end of the cavity or the cavity against ingress of the cathode and allows ingress of the secondary electrolyte from the sodium metal halide salt melt.

[0041] The aforementioned opening at the lower end of the cylindrical lower section of the current collector sidewall can also be modified by forming. For example, the opening can be pressed into a slot, star, or cross shape by pressing the current collector sidewall, whereby a substrate is inserted before pressing, or the opening is reduced by pressing in such a way that secondary electrolyte can penetrate but not the cathode. The substrate preferably acts as a barrier for the cathode.

[0042] Furthermore, it may be preferred if a) the pantograph side wall has no openings except for the at least one through-hole in the separating area, in particular in the pantograph side end wall.

[0043] According to a particularly preferred embodiment, the problem is solved by an electrochemical sodium metal halide secondary cell comprising a housing with a central axis and a separator permeable to sodium ions extending equidistantly to the housing around the central axis of the housing, which has a separator wall, in particular an integral separator wall.

[0044] It is preferred that, in an alternative design, the current collector has no external elements that increase the surface area. Preferably, in this alternative, the current collector has no additional external structures such as waves, grooves, slots, or slots, and / or no relief-forming structures such as crimp edges, metal tufts, folded sheets, and / or fins.In a further alternative, it may be preferred that the current collector has, as an external element for increasing the surface area, a lower region with a current collector side wall with a cavity, the inner diameter of which is larger than the outer diameter of the filling region and / or the outer diameter of the transition region adjoining the separation region below, in particular a cylindrically shaped lower region of the transition region, which is surrounded and / or contacted by the lower region with a current collector side wall with a cavity, in particular a cylindrical lower region with a current collector side wall.

[0045] In an alternative, particularly preferred embodiment, the current collector has a lower hollow, cylindrical section extending into the cathode and a separating section located above the cathode. A separation zone is arranged between the hollow, cylindrical section and the separating section. The separation zone is impassable to the cathode. The separation zone can be a hollow section containing a further substrate with a barrier function, e.g., as a filter or membrane, which is, for example, positioned between one or more inwardly projecting grooves into the current collector, and / or the separation zone corresponds to a cross-sectional narrowing of the current collector side wall, with an optional transition zone to the cross-sectional narrowing of the separation zone located between the separation zone and the hollow, cylindrical section.The transition area is formed in its lower area, preferably partially to completely, complementary, in particular to the upper area, of the lower area with current collector side wall with cavity, wherein the lower area of ​​the transition area is electrically conductively contacted with the lower area with current collector side wall, preferably the upper area thereof, preferably mechanically and / or materially bonded.

[0046] The aforementioned at least one microhole preferably has an inner diameter of less than 0.5 mm, independent of other microholes. The microholes can be arranged regularly and / or irregularly distributed over the entire surface of the cylindrical side wall and may optionally be arranged in groups or form patterns. A regular arrangement of the microholes is preferred. The microholes are preferably dimensioned such that the penetration of secondary electrolyte into the cavity is possible while preventing the penetration of the cathode, in particular the cathode granules.In another alternative, the current collector side wall can have holes larger than the microholes, preferably holes with an opening greater than or equal to 0.5 mm, wherein in this alternative a substrate, in particular a carbon felt, is arranged inside the cavity that covers the holes inside the cavity so that the cathode, in particular cathode granules, cannot penetrate and / or the secondary electrolyte, in particular liquid secondary electrolyte, cannot penetrate into the cavity.

[0047] In a preferred embodiment, the current collector side wall can be completely closed except for the opening(s) in the separator area. In alternative embodiments, the current collector side wall can have micro-holes or holes in the lower cylindrical area, these holes being sealed on the cavity side with a substrate as defined above. In a further alternative, the current collector side wall can be formed from a formed sheet metal and optionally have abutting or overlapping side edges. Advantageously, the current collector side wall is designed and / or formed such that the cavity in the lower area of ​​the current collector is accessible to the secondary electrolyte but not accessible to the cathode granules, i.e., it can be used as a reservoir for the secondary electrolyte.

[0048] The cover part can include a current collector wall, a film, membrane, grid and / or mesh, wherein the film, membrane, grid and / or mesh are permeable to the secondary electrolyte and impermeable to the cathode.

[0049] According to an alternative embodiment, the lower, cylindrically shaped area of ​​the current collector side wall extending into the cathode and containing a cavity can have an opening at the lower end of the cylindrically shaped area, which has a substrate as a filter or membrane that closes the lower end of the cavity against penetration of the cathode and allows penetration of the secondary electrolyte from the sodium metal halide salt melt, in particular as a salt melt, or the lower end of the cylindrically shaped area has a current collector wall, a film, membrane, grid and / or mesh permeable to the secondary electrolyte, wherein the current collector side wall, except for the at least one through-hole, in particular in the separation area, a) has no openings and / or b) has at least one microhole with a diameter of less than or equal to 0.5 mm.

[0050] Furthermore, it is preferred that the current collector, in particular the current collector side wall, is made of a nickel alloy with a nickel content of 30 wt.% or more, preferably 45 wt.% or more, and most preferably 99 wt.% or more, particularly 99.2 wt.% nickel, in the overall composition. Nickel alloy 2.4068 is preferred. The high nickel content in the nickel alloy also contributes to high corrosion resistance, which further improves the cycle life of the secondary cell.

[0051] Furthermore, it is preferred if the current collector, in particular the current collector side wall, and especially preferably the outer current collector side wall, has a surface without surface-enlarging elements and / or a smooth surface. A surface with a roughness greater than or equal to 17 micrometers Ra, and particularly greater than 12.5 micrometers, is considered to have a surface roughness. Preferably, the current collector is made of at least one untreated tube or at least one sheet, particularly with a surface roughness less than or equal to Ra 6.0 micrometers to 0.2 micrometers. Most preferably, the current collector does not include any relief-forming structures, such as crimp edges, metal tufts, fins, or folded sheets, on the outer current collector side wall.Alternatively, the pantograph can have a relief-forming structure, such as grooves, whereby in particular the surface can have an Ra value of 0.1 to less than or equal to 12.5 micrometers, in particular less than or equal to 10 micrometers, in addition to the relief-forming structure.

[0052] A secondary cell according to the invention, the battery module, the system (AA), the battery kit and / or the energy storage system comprising these, have a longevity of greater than or equal to 5 years, preferably greater than or equal to 10 years, more preferably greater than or equal to 15 years, preferably greater than or equal to 20 years, particularly due to the coordinated components and parts as well as their specific composition and / or configuration of the modules as well as the processor orchestration level.

[0053] Likewise, a secondary cell, battery module, system (AA), battery kit, and / or energy storage system can have one or more, two or more, and in particular at least three charge / discharge cycles per day, i.e., within 24 hours. A charge / discharge cycle is defined as 80% of the usable electricity or the electrical charge of the battery in ampere-hours (Ah). With multiple charge / discharge cycles per day, partial capacities, for example, three times 60 Ah, can be present in a state of charge (SoC) range of 20% to 80%. Three to five charge cycles per 24 hours are preferred, and three to four charge cycles per 24 hours are particularly preferred.Preferably, due to the synergistically matched components and compositions, more than 80%, preferably more than 95%, of the secondary cells, battery modules, systems (AA), and / or energy storage systems comprising these exhibit 3 to 5 charge / discharge cycles per 24 hours, particularly coupled with a service life of 5 years or more, preferably 15 years or more. Furthermore, it is more preferred that a secondary cell, battery module, system (AA), battery kit, and / or energy storage system comprising these exhibit a cycle life of 3000 or more, preferably 3500 or more, and particularly preferably 4000 or more, wherein the capacity is preferably 100 Ah and a charge / discharge cycle is limited to 80% of the extractable amount of electricity or the electrical charge of the battery in ampere-hours (Ah).

[0054] It is particularly preferred if the center point of the current collector opening, especially the circular opening, is preferably located on the central axis of the housing. Furthermore, it is preferred if the separator has a central axis that lies on the central axis of the housing, and the current collector has a central axis that also lies on the central axis of the housing. Therefore, it is preferred if these axes have an identical trajectory.

[0055] Advantageously, the at least one through-hole, and in particular the two to four through-holes, each have an independent diameter of 5 to 15 mm, preferably 9 mm, optimally ± 0.5 mm. The through-holes preferably serve exclusively for filling the cathode with cathode material, while simultaneously preventing any cathode material from penetrating the cavity, particularly the lower cavity, of the current collector below the separation zone. The through-holes can be produced by punching or laser cutting.

[0056] The aforementioned micro-holes can be created in the pantograph sidewall using methods such as lasers or punching. The use of micro-holes is an alternative, although it is preferred not to include any micro-holes. If micro-holes are used, it is preferred that the diameter be less than 0.4 mm, preferably less than 0.3 mm, more preferably less than or equal to 0.2 mm, and particularly preferably less than 0.1 mm. The micro-holes can be created as a plurality of holes in the pantograph sidewall. Alternatively, the micro-holes are created in the lower region of the pantograph sidewall, preferably in the lower region corresponding to 1 to 50% of the height of the lower cavity, more preferably 1 to 10% of the height of the lower cavity, wherein the height of the lower cavity is measured at the lower region, particularly the cylindrical region, of the cavity.Likewise, the pantograph side wall, in particular as a shell, may have micro-holes formed from u- or v-shaped slots that are introduced into the pantograph side wall and whose inner area has been bent outwards towards the separator, in particular the separator inner wall.

[0057] According to the invention, it is also preferred that the separation area is arranged above the cathode compartment and thus above the cathode. An integral separator wall is understood to be a separator wall that is integrally formed with the separator. A secondary electrolyte, which embeds the cathode, in particular the cathode granules, as a matrix, and especially completely embeds it, enables sodium ion transport. The secondary electrolyte can preferably penetrate the intraparticle porosity and / or the interspace porosity as a matrix; in particular, the secondary electrolyte can penetrate the total porosity of both the intraparticle and interspace porosity.

[0058] According to a preferred embodiment, the separator is a tubular body open at one end with two opposite ends, preferably having a sac-like or hemispherical shape at one of its two ends, particularly at the lower end, such that the separator separates the anode compartment of an anode from the cathode compartment of a cathode, particularly in the area below the current collector. Preferably, the second end of the separator is arranged at the upper end of the secondary cell in the inactive area.

[0059] Furthermore, it is particularly preferred that the separator, being electrically insulating and preferably a solid primary electrolyte, separates the anode compartment from the cathode compartment, yet is permeable to sodium ions, particularly at temperatures above 200 to 350 °C, preferably at 250 to 350 °C or higher, and especially preferably at 270 °C with a deviation of ±15 °C. Above a temperature of 255 °C or higher, the resistance of sodium ion conduction decreases. Thus, above a temperature of 255 °C or higher, a sodium ion conductivity of 0.19 S / cm or higher, and particularly 0.2 S / cm or higher, can be achieved in the secondary cell at temperatures above 265 °C or higher, preferably at temperatures above 270 °C or higher (measured by impedance spectroscopy on prismatic samples with gold or molten salt contacts). In particular, the separation of the anode from the cathode is electrically insulating and hermetically gas-tight.The gas tightness can be determined by means of a helium leakage measurement.

[0060] Generally, the larger the surface area of ​​the current collector, the better the performance of the secondary cell. Furthermore, the resistance decreases as the ratio of the current collector's diameter to the separator's internal surface area increases. Additionally, the internal resistance of the secondary cell decreases with an increasing diameter of the current collector's side wall, i.e., when the active surface area of ​​the current collector is increased and, in particular, the cathode thickness decreases. It is advantageous to choose the largest possible active surface area of ​​the separator to minimize the internal resistance.

[0061] Furthermore, it may be particularly preferred if, for a separator with a height of 350 mm and a diameter of 45 mm, the cylindrically shaped area of ​​the current collector has an aspect ratio of the height of the area to the inner diameter of the current collector side wall of the area of ​​5 to 70, preferably of 14 to 28, and particularly preferably of 23. The separator side wall preferably has a thickness of 1 to 3 mm, more preferably of 1 to 2.5 mm.

[0062] In an alternative embodiment, it is particularly preferred that, for a separator with a height of 500 mm and a diameter of 45 mm, the cylindrically shaped area of ​​the current collector has an aspect ratio of the height of the area to the inner diameter of the current collector side wall of the area of ​​11.6 to 100, particularly 12 to 100, preferably 20 to 40, and most preferably 30. Consequently, according to an alternative embodiment of the invention, the separators can have a height of 350 mm to 500 mm, including the limit values, wherein the inner diameter of the separator is preferably 45 mm.

[0063] According to a further embodiment, a secondary cell is preferred in which the cylindrically designed area, in particular the circular cylindrical area, of the current collector has an inner wall and an outer wall, and wherein the separator wall of the separator, which is extended equidistantly around the central axis of the housing, has a separator inner wall and a separator outer wall, and wherein the distance of the outer wall of the current collector to the separator inner wall is greater than or equal to 4 mm, in particular from 7 mm to 15.5 mm, in particular from 10 mm to 15.1 mm, preferably + / - 0.05 mm.

[0064] The current collector according to the invention, with nearly identical distances between the separator's inner wall and the current collector's outer wall, exhibits an ideal ratio of enlarged current collector surface area to distance to the separator's inner wall, in order to reduce the contact resistance to metallic components of the cathode. This optimized ratio reduces the internal resistance and power loss of the secondary cell and increases the secondary cell's efficiency.

[0065] In principle, the cavity in the lower cylindrical section of the current collector is adapted to the volume of the cathode in such a way that sodium aluminum chloride can enter the cavity for storage. The cathode is preferably completely embedded in a matrix of secondary electrolyte. During discharge of the secondary cell, the volume of the cathode increases, allowing the secondary electrolyte to compensate for this increase by penetrating the cavity of the lower section. Nevertheless, the cathode remains embedded in the secondary electrolyte.

[0066] According to one embodiment, the current collector can be formed from one or more sheet metal parts as described above, in particular each independently formed into a cylinder, which optionally each was further formed independently, preferably into a first area comprising a separating and / or transition area, and a second area, in particular a second cylindrical area, and optionally the sheets are arranged overlapping at the butt edges and / or joined by material bonding or formed from one or more tubes and formed accordingly, wherein in particular the at least one through hole was punched or laser-cut.

[0067] According to one embodiment, a current collector is preferably formed from a tube, in particular a cylindrical tube, preferably a circular cylindrical tube, and formed, in particular, according to the definition of the current collector's geometry. Alternatively, it may be preferred if the current collector is formed from a sheet metal part into a tube, in particular a cylindrical tube, and in particular, the side edges may abut, overlap, or the abutting or overlapping side edges may be joined by a material bond. This is done, in particular, by laser welding, especially without welding wire, and optionally by subsequent polishing.

[0068] On average, it is preferred if the current collector has a large surface area relative to the inner surface of the separator; preferably, the surface area of ​​the current collector is greater than or equal to 20% of the inner surface of the separator up to 120% of the inner surface of the separator. Particularly large surface areas for a current collector can be achieved if a sheet with a plurality of holes, especially homogeneously distributed over the surface of the sheet, is provided, and optionally, at least one wire or pin, possibly with a head located on the back of the sheet, is inserted into each hole, and the sheet is then formed, especially into a cylinder.The invention therefore also relates to a current collector which in the lower area consists of at least one formed sheet metal, in particular with a cylindrical cross-section and a plurality of holes, which are provided with wire and / or pin protruding from the sheet metal in the direction of the inner separator surface and which are preferably fixed in the holes.

[0069] Furthermore, a preferred embodiment is one in which the current collector is made of a sheet metal part formed into a cylinder, in particular a circular cylinder, and optionally bonded at the butt joints, or of a tube, in particular a hollow tube, wherein in particular the at least one through-hole is punched or laser-cut. Preferably, the current collector is a metal tube or a sheet metal part formed into a metal tube and optionally bonded, in particular joined, with an electrical conductivity of s > 10 6S / m, at 0 °C, preferably an electrical conductivity of s > 1.210 6 S / m at 0 °C, especially greater than 15.10 6 S / m at 0 °C, preferably greater than or equal to 20·10 6 S / m at 0 °C, particularly preferably greater than or equal to 50·10 6 S / m at 0 °C, preferably greater than or equal to 60·10 6 S / at 0 °C. Preferably, the aforementioned cycle strength is achieved. Such a sheet is preferably welded by laser using a material-bonded process without welding material.

[0070] The current collector of the invention preferably has a cavity as a reversible reservoir for the secondary electrolyte, wherein the cavity can be partially or completely filled with secondary electrolyte in a reversible manner.

[0071] Furthermore, it is preferred if the upper filling area, in particular the cylindrical filling area, of the current collector, especially after filling with the cathode and the secondary electrolyte, particularly the porous mixture of the cathode and the secondary electrolyte, is closed with a sheet metal disc or a deep-drawn part bonded to the metal. It may be further preferred if the upper cylindrical filling area of ​​the current collector, especially after filling with the cathode and the secondary electrolyte, particularly the porous mixture of the cathode and the secondary electrolyte, is crimped at the upper end of the cylindrical filling area of ​​the current collector or hermetically sealed with a soldered or welded seam.

[0072] According to the invention, a cylindrical region or cylindrical is understood to mean a geometry of a general cylinder according to the mathematical definition. Examples of such cylindrical regions or cylinders include circular cylinders, elliptical cylinders or prisms, and generally polygonal cross-sections. Preferably, according to the invention, a cylindrical region is circular-cylindrical.

[0073] Furthermore, it is preferred that the separation zone is arranged above the cathode in the secondary cell within the separator. It is also preferred that the separation zone is a pressed section of the current collector, which is in the form of a hollow tube or a cylindrically shaped sheet, and is particularly flattened from two collinear directions.

[0074] According to another alternative, it is preferred that a pressed section of the lower part of the current collector is compressed by force such that a cavity forming as a secondary electrolyte reservoir is exactly the same size as the volume of secondary electrolyte required in the fully charged state of the cell for complete wetting of the current collector and / or the cathode, in particular the cathode granules, in the electrochemically active area. The cross-section of the lower part and the cavity can be of any desired shape. Furthermore, the electrochemically active area is located below the separation zone.Thus, the volume of the lower cavity, in particular the lower inner cavity, of the current collector is adapted to a volume of secondary electrolyte required in the fully charged state of the secondary cell for complete wetting of the current collector and / or the cathode, particularly in the electrochemically active area.

[0075] However, a lower cavity, in particular of the cylindrical area, preferably a cylindrical cavity, preferably a circular cylindrical cavity, which is preferably located below the separation area and extends to the lower end of the cylindrically shaped area to the opening or to the cover part or in particular to the film, membrane, grid and / or mesh, is particularly preferred.

[0076] Furthermore, a preferred aspect of the invention is a substrate that is in the form of a filter or membrane and has a pore size of less than or equal to 0.5 mm, preferably from 1 micrometer to 450 micrometers, more preferably from 50 micrometers to 450 micrometers, and particularly preferably less than or equal to 0.1 mm. The substrate preferably serves as a barrier to the cathode, in particular the cathode material, more preferably the porous mixture. The substrate can preferably be a textile material, such as fiber-based textile materials, more preferably a felt, in particular carbon and / or graphite felt. Advantageously, the substrate consists of or comprises carbon, in particular amorphous carbon and / or graphitized carbon, graphene and / or carbon black, such as conductive carbon black.It is further preferred that the porosity, in particular the open porosity, of the substrate, especially the felt, is preferably greater than or equal to 60%, more preferably greater than 90%, and most preferably greater than or equal to 93%. The substrate can also be in the form of a pressed formulation, a tablet, an extrudate, or a textile structure that seals the opening against cathode penetration and is permeable to the secondary electrolyte. Alternatively, the substrate can also be made of other porous and inert materials, such as a ceramic, metal membrane, etc., or aluminum oxide. The substrate can be arranged in the opening, the cavity, and / or the separation zone. In particular, it can be inserted into the separation zone, which can be a pressed tube section, prior to pressing.

[0077] In a further embodiment, the substrate can be a carbon felt plug, measured to be oversized with respect to the inner diameter of the cylindrical lower cavity of the current collector. Preferably, the diameter of the substrate is larger than the inner diameter of the cavity, in particular 1 mm larger than the inner diameter. The height of the substrate, in particular of the carbon felt plug, can preferably be from 1 to 10 mm, more preferably from 2.5 to 5 mm. With an inner diameter of 15 mm for the current collector, here a high-performance electrode, and a preferred thickness of the current collector side wall of 0.8 mm, the substrate, in particular a carbon felt, preferably has a height of 4 to 5 mm, in particular 4.6 mm, with the diameter preferably being 14.4 to 14.5 mm. Furthermore, the carbon felt can be rolled with a gap of less than 0.1 to 0.5 mm, in particular with a gap of 0.1 mm.

[0078] The invention also relates to a metallic, cathode-side current collector, wherein the cathode-side current collector (3.2) has an upper filling area (3.5) with current collector side wall (3.8) and inner cavity (3.5.1) and optionally has a contacting area (3.6) of the cathode-side current collector (3.2) adjoining the filling area at the top, and - the current collector (3.2) has a lower area (3.4), in particular an area (3.4) extending into a cathode, with a current collector side wall (3.8) with a cavity (14), and - has a separation area (3.3) between the upper filling area (3.5) and the lower area (3.4), in particular wherein the separation area (3.3) will be or is arranged above a cathode (3), and - wherein the separation area (3.3) has at least one through-hole (3.3.1) connecting the inner cavity (3.5.1) of the filling area with the cathode space (3.1), and - below the separating area (3.3) with at least one through-hole (3.3.1) the pantograph (3.2) has a separating area (3.7), - wherein the separation area (3.7) separates the inner cavity (3.5.1) in the filling and separating area from the lower cavity (14) in the lower area, in particular the separation area is not passable for cathode, secondary electrolyte and / or anode, particularly preferably the separation area is not passable for the cathode (3), and, - wherein the current collector (3.2) in the lower area (3.4) with current collector side wall (3.8) with cavity (14), in particular in the area (3.4) extending into the cathode with current collector side wall (3.8) with cavity (14) is designed such that the cathode does not penetrate into the cavity (14) and optionally the cavity (14) is accessible to the secondary electrolyte (7).

[0079] According to a preferred alternative, it is preferred that the cavity, particularly in the lower region, has a shell which is permeable to the secondary electrolyte and not permeable to the cathode, and / or that the cavity, particularly in the lower region, has partially or completely a substrate which is permeable to the secondary electrolyte and not permeable to the cathode.

[0080] According to another alternative, the current collector can have a substrate as a filter or membrane in the cavity in the lower region (3.4) of the current collector side wall (3.8) extending into the cathode (3), in particular in the lower end of the region (3.4) of the current collector side wall (3.8), in particular wherein the substrate (6) closes the lower end of the cavity (14) or the cavity (14) against penetration of the cathode (3) and allows penetration of the secondary electrolyte (7), preferably molten secondary electrolyte, from the sodium metal halide salt melt.

[0081] According to another alternative, the current collector (3.2) can be designed in multiple parts, in particular the current collector comprises a first area (11.1) which includes the filling area, separation area (3.3) and separation area and optionally a transition area (15) adjoining the separation area below, and a second area (11.2) comprising the lower area (3.4) with current collector side wall and optionally with transition area (15), wherein the first and second areas are electrically conductively connected to each other, in particular by means of a material bond, especially preferably by means of a nickel alloy and / or the first and second areas are coated with a nickel alloy.

[0082] A multi-section pantograph can comprise a first section consisting of a single component comprising the filling, separating, and disconnecting area, and optionally a transition area. Furthermore, the multi-section pantograph can comprise a second section consisting of a second component comprising the lower section with a cavity and optionally a transition area located at the top of the lower section. The pantograph can include further components.

[0083] According to a particularly preferred alternative, the current collector is elongated and designed as a hollow tube or formed from a hollow tube and optionally a sheet metal part. The current collector is preferably a metallic cathode-side current collector (3.2), particularly wherein the current collector is formed in one piece or in multiple parts. - wherein the current collector (3.2) has an upper cylindrical filling area (3.5) with current collector side wall (3.8) and inner cavity (3.5.1) and optionally a contacting area (3.6) of the cathode-side current collector (3.2) adjoining the filling area at the top, and the current collector has a lower cylindrical area (3.4) of the current collector side wall (3.8) extending in particular into the cathode (3) and having a cavity (14), as well as a separating area (3.3) of the current collector side wall (3.8) formed between the upper filling area (3.5) and the lower area (3.4), - in particular wherein the separation area (3.3) is arranged above the cathode (3), - wherein the separation area (3.3) has at least one through-hole (3.3.1) and a separation area (3.7) is arranged below the separation area with at least one through-hole (3.3.1), wherein the at least one through-hole (3.3.1) connects the inner cavity of the filling area (3.5) with the cathode space (3.1), - wherein the separation area (3.7) in particular separates the inner cavity in the filling and separation area from the lower cavity in the lower area, in particular the separation area is not passable for cathode, secondary electrolyte and / or anode, in particular preferably the separation area is passable for secondary electrolyte, and optionally the lower, in particular extending into the cathode (3), cylindrically shaped area (3.4) of the current collector side wall has a substrate, in particular a substrate permeable to the liquid secondary electrolyte.

[0084] According to an alternative, the current collector (3.2) is made of a nickel alloy, in particular a nickel-iron alloy, with a nickel content of greater than or equal to 50 wt.%, in particular greater than 70 wt.%, and most preferably greater than or equal to 90 wt.% in relation to the total composition of 100 wt.% of the nickel-iron alloy.

[0085] A substrate is arranged in the separation area, in particular the substrate is clamped and fixed in the separation area.

[0086] An insertion aid for filling the cathode into the cell, in particular an insertion aid with a funnel-shaped lower and upper region, wherein the lower region can be inserted into the filling area of ​​the current collector or placed on the current collector, in particular placed congruently, and the upper region widens in a funnel shape. The invention also relates to a kit comprising at least one current collector and at least one insertion aid.

[0087] According to another alternative, a current collector, synonymous with current collector, is made of a nickel alloy, in particular a nickel-iron alloy, with a nickel content of greater than or equal to 90 wt.%, particularly preferably greater than or equal to 99 wt.% nickel, particularly preferably greater than or equal to 99.2 wt.% nickel, further preferably greater than or equal to 99.6 wt.%, preferably greater than or equal to 99.9 wt.% nickel in relation to the total composition of 100 wt.% of the nickel-iron alloy. A nickel alloy Ni2O1 is particularly preferred. A further preferred option is the current collector made of a nickel alloy comprising greater than or equal to 98.5 wt.% nickel, in particular greater than or equal to 99 wt.%, preferably greater than or equal to 99.2 wt.% nickel, alternatively preferably greater than or equal to 99.6 wt.% nickel, and less than or equal to 0.4 wt.% iron, less than or equal to 0.35 wt.% manganese, and less than or equal to 0.35 wt.% silicon, in particular less than 0.15 wt.%, less than or equal to 0.25 wt.% copper, and less than or equal to 0.020 wt.% copper.-% carbon and / or less than or equal to 0.010 wt.%, in particular less than 0.005 wt.% sulfur, and optionally less than or equal to 0.15 wt.% titanium and optionally less than or equal to 0.15 wt.% magnesium, wherein the total composition is 100 wt.%.

[0088] The current collector is preferably made of, or coated with, a nickel alloy exhibiting an electrical resistance (µΩ*cm) of 19 to 33 (µΩ*cm) in the temperature range of 200 to 400 °C. Furthermore, it is preferred that the electrical contacts consist of, or are coated with, this nickel alloy; the coating should preferably have a layer thickness of 10 to 100 micrometers, more preferably 10 to 50 micrometers. The nickel alloy layer should preferably be defect-free and / or homogeneous.

[0089] In a preferred alternative, the current collector has a core made of a copper alloy, an aluminum alloy, iron, an iron alloy, gold, silver, or an alloy comprising at least one of these metals, with a coating of a nickel alloy, in particular a nickel-iron alloy, and / or molybdenum alloy, wherein the coating has a thickness of 10 to 100 micrometers, preferably 10 to 50 micrometers. In a further alternative, the current collector may consist of gold or a gold alloy. The coating preferably completely encases the current collector. Preferably, the coating is homogeneous. The coating can be deposited in an immersion bath or electrochemically. Nickel-plated copper, iron, or aluminum alloys are less preferred for permanent electrochemical applications if a defect in the nickel coating cannot be ruled out.

[0090] According to another alternative, a current collector, synonymous with current collector, is preferably made of a molybdenum alloy with a molybdenum content of 30 wt.% or greater, and in particular 40 wt.% or greater, optionally comprising titanium dioxide, in relation to the total composition of 100 wt.% of the molybdenum alloy. Alternatively, alloys containing gold and / or platinum may also be used instead of a molybdenum alloy.

[0091] According to another alternative, a current collector, synonymous with current collector, is made of a nickel alloy with a nickel content of 40 wt.% or greater, particularly 45 to 50 wt.% nickel, and optionally a molybdenum content, particularly a molybdenum content of 40 wt.% or greater, and optionally an iron content of 100 wt.% of the total composition of the nickel alloy, preferably as a coating on a molybdenum alloy. An exemplary alloy is Ni-Mo-Fe alloys, such as Hastelloy 2.4617. Alternatively, alloys containing gold and / or platinum can also be used instead of a molybdenum alloy.

[0092] For example, if a cathode with ZnCl₂ or FeC granules is used, the current collector can be made of copper if the cell voltage is chosen to be lower than the voltage at which the copper (approx. 2.6 V) reacts with the salt via the secondary electrolyte to form CuCl₂ or CuCl₂. The use of nickel or molybdenum as a protective layer is also a reliable way to protect the current collector from disintegration, so aluminum can also be used as a current collector material, especially as a tube or sheet, provided the protective layer is free of defects. However, depending on the cell chemistry (e.g., CuCl, CoCl₂, CrCl₂, or ZnCl₂), other material combinations can also be chosen. Using molybdenum instead of nickel can further increase the cell's performance.

[0093] According to a further alternative, it is preferred that the separator is made of a sodium β-aluminate, in particular comprising sodium β'-aluminate and / or sodium β''-aluminate in the mixture, and especially preferably comprising zirconium dioxide, optionally comprising Y₂O₃, and optionally titanium dioxide. Preferably, the zirconium dioxide content in the sodium β-aluminate is 5 to 15 wt.%, and optionally the titanium dioxide content is 0.1 to 2.5 wt.%, based on the total composition of 100 wt.% of the separator. Zirconium dioxide, particularly in the cubic phase, imparts sufficient hardness, toughness, and wear resistance to the separator, especially without negatively affecting the sodium ion conductivity. A particularly preferred zirconium dioxide is stabilized Y2O3, preferably 85 to 95 wt.% ZrO2 and 5 to 15 wt.% Y2O3, particularly preferably 85 to 90 wt.% ZrO2 and 10 to 15 wt.% Y2O3.-% Y₂O₃ in relation to the total composition of 100 wt% zirconium dioxide and Y₂O₃, particularly with cubic phase. A defined titanium dioxide content serves to adjust the sintering temperature. The green compact can be sintered at 1400 to 1600 °C for approximately 26 to 36 hours, including a heating phase from cold to hot to cold. This heating phase can take place within minutes to days. Most preferably, the separator comprises zirconium dioxide, particularly cubic zirconium dioxide. This cubic zirconium dioxide can be transformed into tetragonal zirconium dioxide by phase transformation upon mechanical stress on the separator. This phase transformation leads to a volume expansion. Likewise, the structure can absorb energy through the phase transformation, thereby reducing or stopping crack formation. A so-called transformation strengthening takes place in the separator.Furthermore, the zirconium dioxide particularly preferably contains Y₂O₃, which stabilizes the cubic high-temperature phase of ZrO₂ at room temperature. In addition, the presence of zirconium dioxide controls the grain size distribution; in particular, small zirconium dioxide particles reduce crack propagation by absorbing crack energy.

[0094] Preferably, the separator is free of Na₂ZrO₃; more preferably, the proportion of Na₂ZrO₃ in the separator is less than or equal to 0.5 wt%, and further preferably less than or equal to 0.01 wt%. The separator should be free of Na₂ZrO₃ because this compound does not conduct sodium ions and does not exhibit the mechanical properties of ZrO₂. Furthermore, the formation or proportion of Na₂ZrO₃ in the separator can be reduced by selecting the correct molar ratio of Al₂O₃.

[0095] In a particularly preferred embodiment, the separator consists of sodium β-aluminate phase(s) to a greater than 85 wt.%, in particular greater than 90 wt.%, preferably greater than 95 wt.%, and preferably has a sodium β''-aluminate content of 70 to 99.9 wt.%, in particular greater than 85 to 95 wt.%, in relation to 100 wt.% of the total composition of the sodium β-aluminate phase(s) of the separator, in particular the total composition of the separator comprises 5 to 15 wt.%, preferably 5 to 10 wt.% zirconium dioxide or 5 to 10 wt.% of a zirconium dioxide stabilized with Y2O3. Where the 5 to 10 wt.% zirconium dioxide preferably comprises 85 to 95 wt.% ZrO2 and 5 to 15 wt.% Y2O3, particularly preferably 85 to 90 wt.% ZrO2 and 10 to 15 wt.% Y2O3 in relation to the total composition of 100 wt.% zirconium dioxide stabilized with Y2O3.

[0096] Furthermore, it is preferred that the separator comprises sodium β-aluminate phase(s) comprising sodium β'-aluminate and sodium β''-aluminate, wherein the proportion of sodium β''-aluminate in this phase(s) is greater than 95 wt% of the total 100 wt% sodium β-aluminate phase(s). Optionally, the sodium β-aluminate phase(s) contain 0.2 to 0.39 wt% lithium, particularly as a spinel stabilizer, in relation to the total 100 wt% composition of the separator. Preferably, the separators contain less than or equal to 0.001 to 0.01 wt% Na₂ZrO₃ in relation to the total 100 wt% composition.

[0097] According to another alternative, the separator is obtainable by sintering, in particular reactive sintering, from a pressed white compact or pressed green compact, preferably green compact, comprising a powdered composition of: The separator comprises 60 to 70 wt% Al₂O₃, 10 to 20 wt% Na₂CO₃, 8 to 15 wt% LiAl₅O₈, 5 to 10 wt% ZrO₂, and 0.01 to 5 wt% TiO₂, based on a total composition of 100 wt% of the separator. In both the powdered and aqueous formulations, the aforementioned inorganic components preferably have a particle size of 0.1 to 125 micrometers. The presence of lithium in the composition can positively influence the surface tension of the separator. Furthermore, lithium can lower the firing temperature compared to a composition without lithium, thus contributing to energy savings and improved surface tension of the ceramic. Additionally, lithium stabilizes the crystal phase, maximizing the formation of the β''-phase, which conducts sodium ions.

[0098] Alternatively, the separator is available in an aqueous composition comprising the aforementioned powdered composition, including water and optionally a film former, wherein the total composition of the aqueous composition is 100 wt.%. The water content in the aqueous composition (100 wt.%) can range from 10 to 150 wt.% relative to the aforementioned content of the components in the powdered composition. The powdered composition can preferably be mixed with water and film former in a ratio of 10:1 to 1:2. Optionally, the composition is mixed with water and optionally a film former in a ratio of 1:1 to 1:1.5 to form an aqueous composition for the production of granules, in particular spray-dried granules, wherein the green compact is produced from the granules by pressing, in particular by means of isostatic dry die pressing.Preferably, the granules have a particle size of 10 to 150 micrometers.

[0099] The film former is preferably selected from a cellulose, in particular a high-purity cellulose. Preferably, the film former comprises carboxymethylcellulose and / or sodium carboxymethylcellulose, in particular high-purity sodium carboxymethylcellulose with impurities of less than or equal to 3 ppm wt%, and particularly preferably less than or equal to 0.1 ppm wt%. The separator is then obtainable by reactive sintering of a pressed white and / or green compact. Alternative film formers may include polyvinyl alcohol, optionally mixed with surfactants such as organic carboxylic acids or their alkali and / or alkaline earth salts.

[0100] Furthermore, it is preferred that the separator wall has a wall thickness of 0.5 to 2.5 mm, in particular 0.5 to 2.5 mm or alternatively 0.9 to 1.8 mm, preferably 1.0 to 1.8 mm. At a temperature of 270 °C or above, the sodium ions on the sodium β-aluminate lattice sites become sufficiently mobile to develop adequate ionic conductivity. It is also preferred that the separator wall has a sodium ionic conductivity of greater than or equal to 0.2 S / cm at temperatures above 270 °C, in particular greater than or equal to 0.224 S / cm (from 280.0 °C), and most preferably greater than or equal to 0.262 S / cm (from 310 °C).

[0101] The separator, especially its side wall, exhibits very high radial bending strength as a hollow cylinder. Thus, the bending moment at point F with M is FThe flexural strength (σ) is preferably greater than 180 MPa at point F, and greater than 180 MPa at point 0, and greater than 100 MPa at point 0, particularly with a wall thickness of approximately 1.7 to 2 mm, an outer diameter of 42 to 46 mm, and a length of 20 to 60 cm. The tensile strength (σ) is preferably greater than 180 MPa at point F, and greater than 110 MPa at point 0. The separator material can exhibit significantly higher flexural strengths.

[0102] Also related to the invention is preferably an electrochemical sodium metal halide secondary cell comprising a cathode, wherein the cathode preferably comprises the following composition as components: 50 to 65 wt.% nickel, in particular 55 to 60 wt.%, 25 to 45 wt.% NaCl, in particular 30 to 40 wt.% NaCl, up to 0.45 wt.%, in particular 0.1 to 0.4 wt.% aluminum, in particular an aluminum content of up to 0.45 wt.%, a content of up to 2.5 wt.% Fe(II)S, in particular up to 2 wt.% Fe(II)S, a content of up to 5 wt.% Nal (sodium iodide, NaI; narium iodide (Nal)), in particular up to 2 wt.%, particularly preferably less than or equal to 1 wt.%, and / or a content of up to 6 wt.% NaF, in particular up to 3.5 wt.% NaF, wherein the total composition is 100 wt.%. A composition of the cathode in which the aforementioned components exhibit the preferred amounts is particularly preferred.It is further preferred if the composition, in particular as a powdered mixture, is more preferably in the form of granules, wherein the granules comprise the powdered components or the powdered components with a particle size of 450 micrometers to 2400 micrometers, preferably 450 to 1500 micrometers, more preferably 450 to 1400 micrometers, or 450 to 1300 micrometers.

[0103] Furthermore, it is preferred if the granules do not contain any particles with a particle size greater than or equal to 2 mm, in particular if the proportion of particles with a particle size greater than or equal to 1.5 mm is less than 1 wt.% and / or the proportion of particles with a particle size less than or equal to 200 micrometers is less than 1 wt.%. It is further preferred if the powdered components have a particle size of 1 micrometer to 150 micrometers. It is further preferred if the powdered components have a bimodal particle size distribution, such as nickel with a particle size of 1 micrometer to 10 micrometers, particularly 2 to 5 micrometers, and sodium halides, particularly sodium chloride, sodium fluoride, and / or sodium iodide, with a particle size of 1 to 125 micrometers, particularly 10 to 125 micrometers. Aluminum and / or Fe(II)S may be present with a particle size of 1 to 150 micrometers.Preferably, the granules are obtained by mixing the powdered components for 2 to 20 minutes or even for 20 to 60 hours, followed by granulation in a dry granulator. Aluminum is preferably added as a pore-forming agent.

[0104] Alternatively or additionally, the cathode can be a mixture of metal powders or granulated metal powders, which may include nickel, iron, and / or aluminum, and optionally copper, cobalt, chromium, and / or zinc. The metals preferably form into metal halides only during the subsequent charging of the secondary cell. In addition to the metal powders or granules, the cathode can also include sodium halide(s), in particular sodium chloride, iodide, bromide, or fluoride.

[0105] The secondary cell according to the invention can preferably be designed such that charging to 200% SoC (State of Charge, i.e., the state of charge of the secondary cell), and in particular to 100% SoC, or overcharging, is possible. Therefore, it is preferred if the molar ratio of sodium to metallic nickel (Ni) 0 ) in the overall composition of cathode and secondary electrolyte is from 1 : 1.8 to 1 : 10, in particular from 1 : 1.9 to 1 : 5, especially preferably from 1 : 1.95 to 1 : 2.5.

[0106] In the event of an overcharge of the secondary cell, a higher voltage of at least approximately 3.05 volts is required compared to a charging voltage of 2.58 V, especially 2.8 V, whereby the following charging reaction takes place under normal charging conditions: Ni 0 Überschuss + 2 NaCl ↔ NiCl 2Überschuss + 2 Na 0

[0107] In the event of over-discharge of the secondary cell, especially at a voltage of < 1.58 V, after the complete reduction of NiCl2, the reversible reduction of NaAlCl4 in the catholyte occurs, e.g., in a portion of the secondary electrolyte near the cathode: 3Na 0 + NaAlCl4 ↔ 4 NaCl + Al 0

[0108] During the overcharging reaction, additional sodium is formed from the secondary electrolyte and nickel: 2 NaAlCl4 + Ni 0 ↔ NiCl2 + 2 Na + 2 AlCl3

[0109] Deep discharge protection is achieved by maintaining a voltage limit during discharge of 1.58 V or higher, since at 1.58 V or lower the NaAICI4 is also decomposed as described above.

[0110] Furthermore, a separator preferably relates to a carbon-containing paste, in particular a carbon-containing paste comprising graphite, conductive carbon black, graphene and / or carbon black, especially graphite and carbon black, and a binder, as well as mixtures thereof comprising further components. A binder comprising sodium ions is preferred; more preferably, the binder is a mixture of sodium salts of polyphosphates, in particular with a chain length of 4 to 15, more preferably of 4 to 8, and most preferably sodium hexametaphosphate. The separator is further preferably coated with a carbon-containing paste comprising 40 to 95 wt., in particular 60 to 80 wt., a mixture of sodium salts of polyphosphates and 5 to 60 wt., in particular 20 to 40 wt., a mixture of graphite and carbon black and / or optionally graphene, wherein the total composition of the paste comprises 100 wt.-%, in particular the paste contains a mixture of graphite and carbon black in a ratio of 1 : 10 to 10 : 1, preferably 1 : 1 with + / - 5 %.

[0111] A preferred electrochemical sodium metal halide secondary cell includes a flexible metallic planar element, such as a shim, in particular a metal sheet, preferably a metallic foil, located between the housing and the separator on the outer surface of the separator sidewall. The metallic planar element, in particular the metal sheet, is preferably a flexible metallic element, such as a metal foil, in particular steel, preferably a nickel-plated steel sheet, especially with an electrolytic nickel coating, located on the outer surface of the separator sidewall. The layer thickness can be from 1 µm (micrometer) to 1 mm, preferably from 2 µm (micrometer) to 1 mm, particularly preferably from 0.001 to 0.02 mm, alternatively preferably up to approximately 0.1 mm, designed to hold a film of liquid or solid sodium with variable film thickness in contact with the outer surface of the separator sidewall.The planar element preferably rests against the outer wall of the separator under mechanical tension. In both the discharged and charged states, the element ensures that a sodium ion layer lies flat against the outer wall of the separator, particularly liquid sodium at elevated temperatures, preferably above approximately 100 °C. The planar element may have a fold, especially a closed fold, and may completely surround the separator radially.Furthermore, it is preferred if the planar element has angled fins formed by shaping, in particular vertical fins or fins parallel to the central axis of the housing, which in particular regulate the tension of the planar element and ensure permanent contact of the sodium ions with the separator's outer wall when the anode's volume changes due to incoming sodium, while simultaneously maintaining the sodium film on the separator, in particular over its entire height. The metallic planar element can at least partially rest on a groove, i.e., an inwardly curved, at least partially to fully formed, channel-shaped depression in the housing. In this way, the planar metallic element can bear against the outer side wall of the separator along its entire height, preferably over its entire height.

[0112] Another preferred embodiment comprises an electrochemical sodium metal halide secondary cell, in which the housing is made of a metallic, electrically conductive material and the housing has an anode closure at its top, and the secondary cell has a contact area for the cathode-side current collector. A ceramic insulator ring with an electrically conductive contact, in particular a cylindrical contact, for the contact area of ​​the cathode-side current collector separates the cathode and anode from each other in a non-conductive manner (metal-ceramic composite). Preferably, the ceramic insulator ring is made of Al₂O₃, synonymous with an insulator ring, and can preferably be coated with molybdenum or a molybdenum-containing alloy, particularly for the production of a metal-ceramic composite.

[0113] A zirconium dioxide-free joining glass is preferably used as the joining glass for connecting the insulator ring to the separator (ceramic-ceramic composite). A particularly preferred joining glass is preferably free of zirconium dioxide and comprises, in wt.%, 40 to 50 wt.% silicon dioxide, greater than 25 to 30 wt.% B₂O₃, 5 to 15 wt.% NaO₂, 17 to 25 wt.% Al₂O₃, and from 0 to less than or equal to 2 wt.% metal oxides selected from MgO and / or CaO and / or SrO and / or BaO, as well as mixtures comprising at least two of the metal oxides.

[0114] According to a further embodiment, it is preferred that the secondary electrolyte comprises a sodium metal halide or a mixture of sodium metal halides, wherein sodium aluminum chloride or the mixture of sodium metal halides comprising sodium aluminum chloride is preferred. Particularly preferably, the secondary electrolyte consists of sodium aluminum chloride and optionally sodium halides selected from iodine and fluorine; more preferably, the secondary electrolyte consists of sodium aluminum chloride.The secondary electrolyte is preferably introduced in liquid form as a molten salt into the electrochemical sodium metal halide secondary cell via the contacting area of ​​the cathode-side current collector and the adjoining separation area through the at least one through-hole and / or through the separation area arranged below the at least one through-hole into the cathode compartment, particularly wherein the separation area optionally has an internal opening of less than or equal to 0.5 mm, preferably 0.1 mm, and wherein the molten secondary electrolyte penetrates the cathode compartment and / or the cavity of the lower area, particularly the cylindrically shaped area with the current collector side wall. The aforementioned opening is elongated, in particular a slot, and was formed by pressing the hollow tube or the cylindrically shaped sheet metal.

[0115] The weight ratio of cathode, in particular of a cathode of the aforementioned composition, to secondary electrolyte is 5:1 to 1:1, preferably less than or equal to 2.5:1, and particularly preferably 2.0:1 to 1.5:1. In particular, the cathode has an intergranular porosity of 30 to 50%, preferably 35 to 50%, or a total porosity comprising the internal surface area of ​​the granules of 45 to 75%, particularly 50% to 65%, including the intergranular porosity and the intraparticle porosity (pores in particles of the granules). The intraparticle porosity is preferably 6 to 29%, and particularly 10 to 20%.

[0116] The cathode mixture, in particular the porous mixture, can include the total porosity as well as the interstitial porosity and optionally the intraparticle porosity. The bulk density of the cathode can preferably be from 1 to 4 g / cm³. 3The concentration should be, preferably, 1.5 to 3 g / cm³ 3 .

[0117] According to a further preferred embodiment, one battery module (A) to a plurality of battery modules (A) is claimed.Preferably, a battery module (A) comprises an arrangement of at least two electrochemical sodium metal halide secondary cells, in particular 20 to 500 secondary cells, preferably 48 to 340 secondary cells, which are electrically connected at the respective contact areas of the cathode-side current collectors and the respective contact area of ​​the anodes by electrically conductive conductors. In particular, the secondary cells are connected in series at the contact areas of the cathode-side current collectors and the contact area of ​​the anodes, or the secondary cells are connected in parallel and / or in series in groups, wherein the groups of secondary cells can in turn be connected in series and / or in parallel. Preferably, the battery module has at least one power connection and / or at least one power cable. The power connection and / or the power cable are preferably thermally insulated.The power cables are preferably equipped with contactors, either individually or in groups.

[0118] Preferably, the secondary cells at the contacting areas of the cathode-side current collectors and the contacting area of ​​the anodes are each connected in series with electrically conductive conductors; in particular, all secondary cells are connected in series with electrically conductive conductors.

[0119] Electrical conductors can be connected by plugging, soldering, printing solder paste, welding, or a combination of at least one of these methods. Electrical conductors can be either a conductive cable or a sheet of metal.

[0120] The electrical conductors are preferably copper conductors coated with nickel or a nickel alloy. The conductor is preferably designed as an elongated flat element with a thickness of 0.02 mm to 1 mm, preferably 0.5 mm, and preferably coated with a homogeneous layer of nickel or a nickel alloy, in particular with a thickness of at least 0.1 mm.

[0121] Preferably, at least one electrically conductive conductor of the arrangement of at least two secondary cells, in particular each electrically conductive conductor or at least one electrical conductor of each group of secondary cells, is optionally preferably connected to at least one sensor cable, and the battery module has at least one power connection. The sensor cables are electrically insulated and preferably thermally insulated. The sensor cable taps the cell voltage. A battery module can preferably have a voltage of at least 120 V.

[0122] The secondary cells according to the invention can have an energy density of approximately 80 to 150 Wh / kg, in particular 110 to 130 Wh / kg. Furthermore, discharge rates of 0.25 to a maximum of 1 C (ampere-second (As)) per secondary cell can be achieved.

[0123] The at least one electrical connection is preferably a plug comprising electrical contacts for the power line when the electrical connection is connected to another electrical connection, wherein the electrical contacts of the electrical connection and optionally of the other electrical connection are each embedded in an inorganic, electrically insulating material, in particular in a non-porous and / or hydrophobic material. Suitable inorganic, electrically insulating materials include, in particular, glass, ceramics and / or mixtures thereof, as well as hybrid materials comprising glass and / or ceramics.

[0124] Furthermore, it is preferred if the electrically conductive conductors are arranged as an arrangement of electrically conductive conductors, preferably as an arrangement on a connector plate, and in particular if they are fixed in place, and wherein preferably at least one electrically conductive conductor, in particular each electrically conductive conductor, is connected to at least one sensor cable, or at least one electrically conductive conductor of each group of secondary cells is connected to a sensor cable. It is further preferred that the electrically conductive conductors on the connector plate are pluggable and / or lockable in a reversible manner with respect to the contact areas of the cathode-side current collectors and the contact areas of the anodes.

[0125] Furthermore, it is preferred if the battery module has at least one to three thermal starting systems. A battery module particularly preferably has at least one side wall into which at least one thermal starting system is preferably integrated. Advantageously, the battery module has at least two opposing side walls, each into which at least one thermal starting system is integrated. The thermal starting system can preferably be used generally for supplying thermal energy, in particular for heating the battery module. Thus, the thermal starting system is synonymous with a heating system. The heating system can also serve to maintain and / or adjust or regulate a defined temperature of the battery modules, in particular the secondary cells.

[0126] The thermal starting system, synonymous with heating system, can comprise at least one resistance heater, such as at least one heating element, heating wire, heating mat, or similar device. A heating mat can comprise, as a carrier material, an inorganic fabric, in particular an inorganic textile, especially glass textile, preferably glass fiber fabric. Alternatively, a mica plate may be advantageous. According to the invention, at least one resistance heater is sewn or embroidered onto the inorganic textile. In embroidery, the carrier material is provided with a pattern of the heating wire or wires by drawing or sewing threads through it, in this case, one or more heating wires of the resistance heater. In a particularly preferred embodiment, the carrier material is provided with at least one heating wire of a resistance heater with a defined pattern; in particular, at least one defined pattern of a heating wire is applied.The defined pattern preferably ensures a homogeneous and / or optimal temperature distribution within the battery module and optionally within the system (AA). It is further preferred that two opposing side walls of a battery module each comprise at least one heating system, synonymous with a thermal start system. It is also preferred that each thermal start system, synonymous with a heating system, can be controlled individually or in groups. For example, it may be preferred that the heating systems in each battery module are connected in parallel. Furthermore, each heating system can have one or more heating circuits that are individually controllable. Preferably, one or two processors or controllers in the BMS control a heating system of a battery module, in particular comprising at least one resistance heater. Furthermore, the battery module preferably has at least one thermally insulated power connection.Optionally, the battery module or at least one secondary cell has temperature sensor(s) with cable(s).

[0127] According to a particularly preferred alternative, the invention also relates to a battery module (A) comprising an arrangement of electrochemical sodium metal halide secondary cells, in particular 20 to 500, preferably 20 to 340 secondary cells, preferably 48 to 300 secondary cells, wherein the secondary cells are connected in series at the contact areas of the respective cathode-side current collectors and the contact areas of the respective anodes with electrically conductive conductors, wherein the electrically conductive conductors are arranged as an arrangement of electrically conductive conductors on, in particular on, a connector plate, and are in particular fixed. Optionally, each electrically conductive conductor can be connected to at least one sensor cable.

[0128] In a series circuit, a cathode-side current collector of one secondary cell is electrically connected to an anode-side current collector of another secondary cell via an electrically conductive conductor. According to a further alternative, it may be preferred if one or more groups of secondary cells in a battery module are electrically conductive. Preferably, each secondary cell, in particular its contact area, in a battery module is connected in series to electrically conductive conductors, especially to two other cells. Preferably, at least one sensor cable per battery module is connected to the series circuit. A series connection of the cells, in particular at least one to all battery modules, is particularly preferred. A battery module can preferably comprise two to 340 secondary cells; more preferably, a module comprises 40 to 60 secondary cells, and more preferably, 48 secondary cells.

[0129] The secondary cells can be arranged individually in one or more levels within a module, or in at least two levels within a module. Similarly, arrangements of secondary cells can also be configured.

[0130] In a particularly preferred embodiment, each electrically conductive conductor has a sensor cable, and preferably, each of the respective power terminals of the battery module also has a sensor cable. The individual cell voltage of a secondary cell can be measured and / or monitored via a sensor cable, and in particular via the arrangement of the aforementioned sensor cables. Theoretically, only selected secondary cells can have sensor cables, or only defined sensor cables can be addressed by the BMS, in which case groups of secondary cells can be monitored and / or measured. Individual monitoring is preferred. The battery module is preferably an intermediate product for the manufacture of a system (A) and an energy storage system.

[0131] According to an alternative embodiment of the invention, the invention also relates to a system (AA) comprising a thermally insulated housing (AA.1) with a support (B) as a base, and comprising at least one battery module which is arranged on the support as a base, in particular comprising a thermally insulated base, wherein the housing can be reversibly fixed to the support (B) or is reversibly fixed. In a further alternative embodiment, the housing is screwed to the support, inserted into groove(s) on the support, and / or snapped into place. The system (AA) can preferably be used as a stationary system. The base of the support is suitable as the base of the support and is different from the base of the current collector side wall.

[0132] Furthermore, the invention relates to a system (AA) comprising a thermally insulated housing (AA.1) and at least one battery module arranged in the housing, in particular at least two battery modules, wherein the thermally insulated housing completely encloses the at least one battery module in a thermally insulating manner, and - optionally, the system comprising temperature sensor(s) with cable(s), in particular arranged in the space between the housing and battery module and / or on the outside of the thermally insulated housing, - comprising at least one wiring harness including power cables of the at least one battery module or power cables connected to the power terminals of the battery modules, as well as the sensor cables, wherein the wiring harness is preferably passable through or is routed through the housing. The wiring harness can be routed through thermally insulated bushings. The insulation can be provided, for example, by silicone sealant, glass sealant, hybrid sealant, or combinations thereof. Preferably, the housing is double-walled, particularly as described below. The housing is preferably cuboid in shape and comprises six rectangular side surfaces or four rectangular side surfaces and a bottom surface and a top surface, which are preferably designed as double-walled side walls, a top surface, and a bottom surface and are thermally insulated. The housing is preferably hermetically sealed.

[0133] According to an alternative, the invention relates to a system (AA) comprising a thermally insulated housing, wherein the thermally insulated housing (AA.1) i) is lockable with a support (B), preferably the support is a base part, and comprising at least one battery module, in particular at least two battery modules, according to one of claims 16 to 18, which is arranged on the support, in particular comprising a thermally insulated base part, wherein the housing is reversibly fixed on or to the support or is reversibly fixed, and, wherein the thermally insulated housing and the support completely enclose the at least one battery module in a thermally insulating manner, and / or ii) is closable with at least one thermally insulated element, in particular at least one side wall and / or bottom part and / or lid part or part of at least one of the parts, wherein the housing and the at least one element or part thereof completely enclose the at least one battery module and provide thermal insulation, and - optionally, the system comprising temperature sensor(s) with cable(s), in particular arranged in the space between the housing and battery module and / or on the outside of the thermally insulated housing, - comprising at least one wiring harness comprising power cables of the battery modules or power cables connected to the power terminals of the battery modules and comprising the sensor cables, wherein the wiring harness is preferably passable through or is passed through the support (B) as a base part.

[0134] The thermally insulated element is preferably identically thermally insulated to the housing. Furthermore, the thermally insulated element can be a flat, thermally insulated side wall and / or a thermally insulated cover section, or a thermally insulated part thereof. The housing and the at least one thermally insulated element and / or the thermally insulated support can each be sealed independently of one another, preferably hermetically. Hermetically sealed means that no atmosphere, such as moisture and / or air, in particular oxygen and / or air containing humidity, can enter or escape from the housing. If necessary, atmospheric venting from the housing is possible via a one-way valve.Sealing is possible by means of sealant and screwing, or sealant and welding, or sealant and clamping, or sealant and fixing, in particular releasable or non-destructively releasable fixing.

[0135] According to an alternative embodiment of the invention, the invention also relates to a system (AA) comprising a thermally insulated housing (AA.1) with a support (B) as a base, and comprising at least one battery module, in particular two battery modules, in particular 2 to 10, preferably 5 battery modules, which are arranged on the support as a base, in particular comprising a thermally insulated base, wherein the housing can be reversibly fixed to the support (B) or is reversibly fixed. In a further alternative embodiment, the housing is screwed to the support, inserted into groove(s) on the support and / or snapped into place. The system (AA) can preferably be used as a stationary system.

[0136] According to a further alternative, the invention relates to a system (AA) comprising a thermally insulated housing (AA.1) with a support (B) as a base part, in particular as a stationary system (AA), and comprising at least one battery module, preferably at least two battery modules, which are arranged on the support as a base part, in particular comprising a thermally insulated base part, and wherein the thermally insulated housing and the support completely enclose the at least two battery modules, in particular 2 to 10, preferably 5 battery modules, in a thermally insulating manner, and optionally wherein the system comprises temperature sensor(s) with cable(s), in particular arranged in the space between the housing and the battery modules and / or on the outside of the thermally insulated housing, and, wherein the system (AA) comprises at least one wiring harness comprising power cables of the battery modules or power cables connected to the power terminals of the battery modules and optionally comprising the sensor cables and optionally comprising the cables of the temperature sensors, wherein the wiring harness is preferably passable through or routed through the support (B) as a base part, and, in particular, wherein the wiring harness preferably has at least one analog connection or at least one data connection and at least one charging connection or a common analog and / or charging connection or charging and / or data connection, which is preferably passable through or routed out of the support (B). Alternatively, the respective cables may have analog connections and / or charging and / or data connections in groups or individually.

[0137] In particular, power cables, sensor cables, and cables for temperature and / or humidity sensors are routed separately or within a cable harness to an analog port and a separate charging port, or to a common analog port and charging port, or a charging and / or data port. Preferably, the respective cables are provided with high-temperature-resistant insulation, and in particular, the insulation is equipped with flame retardants. Examples of flame retardants include phosphorus-containing polymers, inorganic flame retardants (aluminum hydroxide), and CO2-releasing additives. The cable harness is preferably passable through the support (B) as the base section, so that the common charging and / or data port can be routed out of the support (B).The insulation can consist of a glass sizing, glass textile, ceramic textile and / or hybrid material comprising a textile comprising metals, metallic alloys, glass or ceramic fibers, wires, nonwovens or yarns, or other textile structures known to those skilled in the art, which are in particular equipped with flame retardants and optionally contain inorganic particles. The insulation can be in the form of a multilayer textile.

[0138] An analog port, synonymous with analog interface, is an electrical connection that transmits analog electrical signals for processing in downstream electrical and electronic devices or components.

[0139] The support, comprising a thermally insulated base section, is designed, together with the thermal housing, to form a thermally insulated enclosure, in particular a complete enclosure, for at least two battery modules, and in particular up to 10 battery modules. The support can be made of an inorganic material, preferably concrete, metal, in particular structural steel, alloy, and / or a sandwich construction, optionally including vacuum-sealed inner areas. The support comprises a thermally insulated base section arranged on the top and a lower base section, in particular made of structural steel. Silicone, in particular as a sheet element, can serve as a seal between the support, in particular the thermally insulated base section, and the housing. The seal is preferably arranged on top of the support to seal the transition to the housing.The support can be designed as a thermally insulated base on the top side and have at least one opening and / or cavity for accommodating cables, sensor cables, electrically conductive conductors, and / or wiring harnesses. The support can also have openings and / or cavities on its underside and / or at least one lateral surface for accommodating and routing optional electronic components and electronic control systems and / or wiring harnesses, such as a BMS, and at least one battery balancer or state machine for monitoring, charging, and / or discharging control.

[0140] Furthermore, it is preferred that the system (AA) comprising battery modules has at least one charging and / or analog connection or one charging and / or data connection; optionally, the system (AA) comprising the battery modules has temperature sensor(s) with cables and preferably an analog interface or data connection; more preferably, the system has at least one analog interface or a data interface and at least one common power connection. The system (AA) is preferably an intermediate product for manufacturing a battery kit for energy storage comprising an arrangement of systems (AA) and an energy storage system.

[0141] Furthermore, the system (AA) or the battery kit comprising the system (AA) preferably includes at least one BMS (Battery Management System), in particular the BMS is arranged in or under the support as a base part or is assigned to the energy storage system mentioned below, wherein at least one first processor is assigned to the at least one BMS or the at least one BMS includes at least one first processor which is adapted to functionally control, analyze, signal forwarding and / or regulate the respective BMS and the respective modules of the BMS, wherein the respective BMS includes at least one analog interface and / or at least one data interface, in particular a bus system, as well as at least one charge state balancing module (Battery Balancer or State Machine) for monitoring, charging and / or discharging control, in particular of the secondary cells, preferably of the secondary cells in the battery module.The charge state balancing module is preferably connected to one or all secondary cells of one or more battery modules.

[0142] The system (AA), a battery module, and / or the battery kit also comprise at least one to a plurality of contactors, which are electronically or electromagnetically actuated switches for switching the secondary cells to enable or prevent charging or discharging. The contactors are designed as electrical switches to be used electronically and / or electromagnetically in the battery module and / or in the system (AA), and / or in the battery kit, in particular to be functionally controlled and / or regulated. According to one embodiment, each contactor, individually, or all contactors in groups or collectively, is assigned at least one contactor processor, which is adapted to functionally control and / or regulate the contactors individually, in groups, or collectively.

[0143] Preferably, a BMS comprises an analog interface, in particular for connecting the battery modules and / or secondary cells, and a data interface, in particular for connecting to an energy storage system. Furthermore, the BMS includes a power connection.

[0144] The charge-state balancing module for monitoring, charging, and / or discharging the secondary cells is preferably assigned at least one first processor, or the charge-state balancing module preferably comprises at least one first processor adapted for functional analysis, signal forwarding, functional control, and / or regulation of the monitoring, charging, and / or discharging control of the charge-state balancing module. The BMS sends signals to the inverter / the EMS (energy management system), in particular to provide information on the state of the secondary cells or the battery module. The BMS can control the secondary cells or the battery modules by means of the contactors in the system (AA) or in the battery modules, in particular by switching them. The control of the secondary cells takes place in the EMS.

[0145] The BMS sends signals to the inverter / EMS to inform it of the current capacity of the cells or battery. One active function of the BMS is its ability to disconnect the secondary cells or battery module using contactors, thus preventing discharge. This occurs, for example, if the inverter / EMS has not responded to previous warnings. The BMS monitors individual voltages, current, and temperatures (in particular, the total voltage of the secondary cells and / or battery modules, transmitted by temperature sensors), as well as the state of charge of the secondary cells, battery modules, and / or the system (AA). When defined limits are reached, signals are forwarded to the inverter / EMS. The more intelligent the BMS, the more information it provides to the inverter. This can also include a prediction of the available power input and / or output.

[0146] Furthermore, the BMS can also include at least one state machine comprising software, optionally a clock generator, analog-to-digital converters and multiplexers, optional module(s) for monitoring cell voltage, and optionally individual cell voltage taps from the sensor cables. The system can include one BMS per battery module, especially if the secondary cells are connected in series.

[0147] Preferably, a state machine is assigned at least one first processor, or the state machine preferably comprises at least one first processor adapted for the functional control and regulation of the state machine. Furthermore, it is preferred if the real-time clock is assigned at least one first processor, or the real-time clock preferably comprises at least one first processor adapted for analysis, signal forwarding, functional control, and / or regulation of the real-time clock. It is also preferred if each of the module(s) for monitoring the cell voltage is assigned at least one first processor, or the module(s) for monitoring the cell voltage preferably comprise at least one first processor adapted for analysis, signal forwarding, functional control, and / or regulation of these modules. For example, a module for monitoring the cell voltage analyzes and monitors...the state of charge (SOC) of the secondary cells, their individual cell voltage, the temperature, especially of the secondary cells or a battery module, the current, the total voltage of the secondary cells or a group of secondary cells and optionally whether there are any defective secondary cells.

[0148] A clock generator serves to generate a system clock in a computer or processor and to control and synchronize the data flow within a computer system. The individual components align themselves to the system clock to ensure that signals are valid at a specific time or within a specific time period. The clock generator can be located within the processor. A multiplexer is an electronic device, processor, or software component that accepts multiple input signals and can transmit them on a single output channel.

[0149] The state machine defines and stores various operating states, such as commissioning, heating, charging, discharging, fast charging, cooling, cold standby, hot standby, service mode, error mode, etc. The target / actual comparison parameters and action instructions can each be defined independently. The measuring range of the module(s) for measuring cell voltage is preferably between 0 and 3 volts. A voltage of 1.7 to 2.8 volts, particularly 2.3 to 2.8 V, is preferred for each charged secondary cell.

[0150] The monitoring of the secondary cell voltage is carried out via individual cell voltage taps on the sensor cables. These signals are converted into digital signals by analog-to-digital converters in the BMS (Battery Management System). The BMS includes at least one primary processor, which is adapted to functionally control the respective BMS and its modules, etc., and to compare and regulate the target / actual parameters and action instructions. For example, if the cell voltage exceeds 2.8 volts, the BMS sends a warning to the inverter / EMS requesting a current reduction. If shutdown limits are exceeded, the BMS opens the contactors and disconnects the system (AA) or a battery module under load, i.e., disconnects the electronic connection.

[0151] Preferably, at least one first processor is assigned to a group or each of the heating systems, synonymous with thermal start systems, or a thermal start system or heating system comprises at least one first processor that is not necessarily located in the start system, but is, for example, assigned to a control unit of the start system, which may be located in the battery kit or externally of the battery module, in particular in system (A), in a BMS or an energy storage system, connected via an analog interface or data interface, such as data cable, radio, WLAN and / or Bluetooth. Preferably, the at least one processor of a thermal start system or heating system is located in an EMS or a BMS. The at least one processor is adapted to functionally control and / or regulate the at least one thermal start system or heating system.The heating system includes at least one analog interface or data interface, in particular a bus system.

[0152] Each thermal start system can be assigned at least one temperature sensor with an analog or data connection. This sensor allows the thermal start system to analyze the temperature in each battery module, particularly each secondary cell and / or group of secondary cells, specifically to determine the temperature in a target / actual comparison and transmit this information to the processor orchestration level. The target temperature is in the range of 270 to 350 °C. If the actual temperature, particularly during standard operation, is below 270 °C, the heating system or thermal start system is activated, and at least one heating element, such as a resistance heater, is switched on until the target temperature of 270 °C or higher is reached. Above 350 °C, passive cooling is used. Alternatively, an active cooling system can be activated.

[0153] If a temperature deviating from the setpoint temperature is detected in a battery module and / or a secondary cell and / or group of secondary cells and transmitted to the processor orchestration level (POL), the POL can perform a setpoint / actual temperature comparison and send a control signal to the thermal start system for its regulation, specifically to the processor of the thermal start system, thereby activating a heating element. Alternatively or additionally, as a safety measure, a humidity sensor can be used to measure the humidity of one or all battery modules and / or batteries, internally and / or externally. If the humidity deviates from a setpoint value, an alarm can be triggered, or the control signal can be transmitted to the POL.

[0154] Furthermore, the system (AA) preferably includes at least one hotbox and a BMS network. The hotbox can monitor and regulate humidity and temperature for the system (AA).

[0155] The thermally insulated housing preferably comprises double-walled hollow side walls that are at least partially or completely filled with an insulating material and / or the double-walled side walls are vacuum-insulated. The thermally insulated housing is preferably hood-shaped and consists of five side walls, in particular four lateral side walls and a top side wall. The hood-shaped housing can preferably be thermally insulated, in particular with an intermediate seal, preferably a silicone seal, and mounted on the support and fixed reversibly or permanently. Side walls with a sandwich construction are also considered double-walled.It is particularly preferred if the double-walled, hollow side walls, in particular side walls made of steel, preferably stainless steel, are partially or completely filled with an insulating material, wherein the material comprises or is selected from pyrogenic silica, in particular aerogel or Aerosil®, in particular Aerosil® 200 with a very low specific density of 2.2 g / cm³. 3 Preferred materials are porous plates made of silica, glass wool, rock wool, glass foam, silicate foam, such as foamed glass gravel, hollow glass spheres, such as micro hollow glass spheres, especially with a density of 0.15 g / cm³. 3 up to 0.60 g / cm² 3Fiberboards, foamed polymers, in particular foamed carbon-containing polymers as a hybrid material comprising O, N and / or S atoms, especially with a high temperature resistance of greater than 370 °C, particularly comprising PIR (polyisocyanurate) with EPDM (ethylene propylene diene monomer rubber), PAEKs such as PEEK-PEDEK, PEDEK, preferably foamed PAEKs, particularly preferably PAEK with a high proportion of intraparticle porosity, wherein the PAEKs can be in the form of polymer sheets formed from particles that are metallurgically bonded at the contact points of the particles, e.g. by chemically dissolving and solidifying the contact points, and / or as a bed of particles. The insulating material can preferably be in the form of granules or sheets made of granules, foam, fibers and / or a combination thereof.Preferably, a plate has mechanically supporting and thermally insulating properties and is optionally porous, so that in the event of a failure the cathode and / or anode can be accommodated in the porous plate.

[0156] The aforementioned inorganic materials, such as pyrogenic silica, glass wool, rock wool, or foamed carbon-containing polymers as hybrid materials, preferably include flame retardants and retain their respective insulating properties in the event of battery or battery kit failure. They can also accommodate cathode and anode components, in particular absorbing and advantageously binding them as a solid. Liquid materials are preferably avoided as insulating materials because their insulating capacity is significantly lower than that of vacuum and / or solid materials with or without cavities.

[0157] Particularly preferred is insulating material comprising, in particular selected from porous sheets of silica, glass wool, rock wool, foam glass, silicate foam, hollow glass spheres and / or fiberboards with a thermal conductivity at 300 °C of less than or equal to 8 mW / mK, preferably less than or equal to 5 mW / mK, and particularly preferably less than or equal to 3 mW / mK. In particular, the thermally insulated housing, comprising preferably double-walled hollow side walls which are at least partially to completely filled with one of the aforementioned insulating materials, has a vacuum of less than or equal to 0.1 mbar, and in particular a residual gas pressure of less than or equal to 0.1 mbar. More preferably, the residual gas pressure may be less than 0.05 mbar, and more preferably less than or equal to 0.001 mbar or less than 0.0001 mbar. It is further preferred if the aforementioned materials are formed as sheets which partially to preferably completely fill the hollow side walls.

[0158] Silica plates are preferred due to the very low specific gravity of silica. Furthermore, the thermal conductivity of the thermally insulated housing can be reduced to a value of less than or equal to 0.0059 W / mK, preferably to less than or equal to 0.005 W / mK up to 0.0045 W / mK, and more preferably to 0.005 W / mK. The thermal conductivity is preferably determined using the laser or light-flash method (LFA) or, more preferably, with a heat flow meter (plate apparatus). The laser or light-flash method can be applied over a very wide temperature range (-125 to 2800°C).

[0159] The double-walled, hollow side walls of the thermally insulating housing are hermetically sealed after the insulating material has been applied and / or a vacuum has been created. The inner distance between the double-walled side walls is preferably 15 to 70 mm, more preferably 15 to 65 mm, and particularly preferably 55 to 65 mm. With the aforementioned thermally insulated housing with double-walled hollow side walls, which are provided with insulating material and / or a vacuum, a heat loss of less than 900 watts (270 °C inside, 20 °C outside), preferably 500 watts, and more preferably less than or equal to 300 watts (270 °C inside, 20 °C outside) can be achieved for a system (AA). The outer wall of the system (AA) preferably has a temperature only 4 to 15 °C higher than the ambient temperature at room temperature (20 to 23 °C), preferably less than 8 °C.Basically, the heat loss for the system (AA) can be adjusted to the number of charging and discharging cycles (full cycles: 20 to 80%) in order to always maintain the desired temperature inside the system.

[0160] The side walls are defined as all walls of the insulated enclosure, including the top and optionally excluding the bottom, so that the insulated enclosure can be reversibly fixed to a support. The support is preferably also thermally insulated and seals the interior of the thermally insulated enclosure airtight and moisture-tight from the environment. The support may preferably have double-walled side walls, analogous to the insulated enclosure, and optionally include an inorganic base, particularly made of concrete. A circumferential silicone and / or Teflon seal is preferably arranged between the enclosure and the support.

[0161] The vacuum can preferably be in the range of 0.1 bar. abs down to 0.001 bar absAlternatively, a getter material can be arranged as an insulating material in the thermally insulated housing. The thermally insulated housing can also have three or more side walls instead of being double-walled, specifically two outer side walls with at least one inner side wall, forming two cavities. Preferably, different insulating materials can be present in the two cavities.The outer of the two cavities can contain an insulating material comprising fibers, in particular metal, carbon, or metallized fibers, preferably graphite fibers and / or aluminum fibers, or air at a total pressure of 0.01 bar to 0.5 bar. The inner of the two cavities can contain a different insulating material, in particular granulated insulating material, plate-shaped porous material, hydrogen gas, and an electrically heated getter material for the absorption and desorption of hydrogen, wherein the inner of the two cavities has switchable thermal conductivity. According to a further alternative, the internal pressure, in particular the vacuum, of at least one cavity of the thermally insulated housing can be adjusted to the temperature conditions of the external environment by means of a vacuum device and / or a compressor device.

[0162] Preferably, a thermally insulated housing comprising internal cavities, in particular the inner of the two cavities, with switchable thermal conductivity is associated with a thermal conductivity system comprising at least one processor, wherein the processor is adapted to functionally control and / or regulate the at least one switchable thermal conductivity system, wherein the switchable thermal conductivity system comprises at least one data interface, in particular a bus system. Furthermore, the processor is adapted to functionally control and / or regulate the absorption and / or desorption of a fluid, in particular hydrogen, on a getter material, in particular an electrically heated getter material.

[0163] In another variant, the system includes at least one humidity sensor with a data and / or charging port for monitoring housing leaks. Preferably, the humidity sensor is not required, as the system is designed to be extremely robust against mechanical stress and weather-related influences.

[0164] In one embodiment, the thermally insulated housing (AA.1) is designed as a hood which is placed from above over an arrangement of modules (A) onto an insulating base plate (AA.2) and is reversibly connected to the base plate (AA.2) or to a support (B) arranged below the base plate.

[0165] The support (B) incorporates a cavity and / or cable entry for accommodating at least one cable harness as an arrangement of cables for the at least two battery modules, preferably the five battery modules. On the underside or in the middle area of ​​the support, particularly on the underside, a structure of the support is adapted to allow the support to be picked up by a fork (C) of a forklift.

[0166] The invention further relates to a battery kit, in particular a battery kit comprising battery modules and / or systems (AA) as a grid arrangement, for energy storage with an energy storage capacity of 60 kWh or greater, particularly for use in the power grid, wherein the battery kit preferably comprises an arrangement of at least two systems (AA), particularly as an arrangement in a container or a grid-shaped support. In a further preferred embodiment, the battery kit comprises 5 to 20 systems (AA), in particular 10 to 20, each with 150 to 300 electrochemical sodium metal halide secondary cells, wherein the battery kit preferably has an energy storage capacity of 1 MWh or greater, in particular nominally 1.08 MWh, and in particular less than or equal to 2 MWh. Energy storage capacities of the battery kit of 550 kWh or greater than or equal to 10 MWh, and preferably of 1 MWh or greater than or equal to 4 MWh, are also preferred.Alternatively, the battery kit can comprise 3,000 to 10,000 secondary cells, preferably 4,000 to 5,000. The nominal voltage of the battery kit and / or the system is preferably between 410 V DC and 670 V DC. The nominal voltage is 600 V DC. The nominal current (amperage (US, current-carrying capacity)) is preferably greater than or equal to 100 Ah (nominal), preferably 25 A or temporarily 33 A. The C-rate (C-rate: charging or discharging current relative to the nominal capacity of the battery in ampere-hours (Ah)) is at least 0.16 C to 0.33 C (bidirectional) during discharge and less than or equal to 0.5 C for 15 minutes during discharge. The nominal cell capacity can be 100 Ah, but it can also be greater or less. The C-rate will also change in this case.

[0167] A battery module preferably has an energy storage capacity of 80 kWh or greater, and in particular 100 kWh or greater up to 500 kWh.

[0168] The invention also relates to an energy storage system, in particular a stationary energy storage system, comprising at least one battery kit, in particular a battery kit with an energy storage capacity of greater than or equal to 60 kWh, in particular greater than or equal to 1 MWh, in particular greater than or equal to a nominal capacity of 1.08 MWh, and / or comprising at least one secondary cell up to a plurality of secondary cells, in particular 5 to 5000, and / or at least two battery modules (A), in particular 50 to 250, and / or comprising at least one system (AA), in particular 5 to 50, and - comprising a processor orchestration level (POL) for the integration and functional control and regulation of the at least one BMS, which is assigned to the at least one battery kit, one or more secondary cells, a group of secondary cells, at least one battery module and / or at least one system (AA), and optionally for the functional control and / or regulation of at least one thermal conductivity system, and in particular for the functional control and regulation of AC / DC rectifiers, especially for charging the at least one battery kit, and / or DC / AC inverters, especially for discharging the at least one battery, each of which is independently assigned at least one first processor or each independently of the AC / DC rectifiers and / or the DC / AC inverters comprises at least one first processor adapted for the functional control and regulation of the AC / DC rectifier and / or the DC / AC inverter,and / or for the functional control and regulation of DC / DC converters, in particular for charging and / or discharging the at least one battery, wherein the DC / DC converter is assigned at least one first processor and / or the DC / DC converter comprises at least one first processor adapted for the functional control and regulation of the DC / DC converter, wherein the energy storage system can be coupled or uncoupled and / or connected to a network, in particular a transmission network and / or distribution network, for the transmission and distribution of electrical energy, and - where, when coupling the energy storage system with the network, the processor orchestration layer (POL) - functionally controls, monitors and / or regulates the feed-in of electrical energy from the energy storage system into the network for the transmission and distribution of electrical energy and / or - the extraction of electrical energy from a network for the transmission and distribution of electrical energy for the storage of electrical energy in which at least one energy storage system is functionally controlled, monitored and / or regulated.

[0169] Furthermore, the Process Orchestration Layer (POL) functionally controls, monitors and / or regulates the coupling and / or decoupling of the energy storage system with the network.

[0170] The power-on-loose (POL) is preferably part of an energy management system (EMS). The energy storage system preferably comprises at least one of the aforementioned AC / DC rectifiers, in particular for charging the at least one battery kit, and / or DC / AC inverters, in particular for discharging the at least one battery, each of which is independently assigned at least one first processor, or each of the AC / DC rectifiers and / or the DC / AC inverters independently comprises at least one first processor adapted for the functional control and regulation of the AC / DC rectifier and / or the DC / AC inverter, and / or at least one DC / DC converter, in particular for charging and / or discharging the at least one battery, wherein the DC / DC converter is assigned at least one first processor and / or the DC / DC converter comprises at least one first processor adapted for the functional control and regulation of the DC / DC converter.The energy storage system includes, in particular, analog interfaces, analog connections, power connections, especially DC power connections and / or AC mains connections, and / or data interfaces.

[0171] The processor orchestration level (POL), especially as part of an EMS, regulates and controls which electrical powers are fed in or out based on target / actual information from a network for the transmission and distribution of electrical energy.

[0172] The at least one BMS assigned to the POL is preferably designated as the master BMS for all other BMS in the battery kits, particularly for the integration, functional control, and regulation of these BMS within the energy storage system. The master BMS can be one of the BMS within a battery kit.

[0173] The processor orchestration level preferably comprises processor orchestration software. This processor orchestration software can execute the orchestration process and serves in particular for the integration and functional control and / or regulation of at least one to all of the subsequent systems (AA) or modules. The systems (AA) and / or modules preferably have their own control software, which is controlled by the processor orchestration software.

[0174] Furthermore, it may be preferred if the processor orchestration level (POL) serves for the integration and functional control and regulation of at least one to all of the following systems (AA) or modules, which include: at least one thermal start system (synonymous with heating system), at least one state machine, at least one real-time clock, temperature sensor(s), humidity sensor(s), level indicator(s), and / or optionally module(s) for monitoring the cell voltage and / or DC / AC inverter(s) and / or DC / DC converter(s). The systems (AA) and / or modules preferably have their own software, in particular for controlling the systems (AA) and / or modules.

[0175] A data interface, or computer interface, is a connection point between two interrelated information processing systems or system components, through which data or control information is exchanged. A processor typically performs calculations, executes instructions, and controls other components that process the information. A processor is also frequently referred to as a "CPU" (Central Processing Unit).

[0176] Furthermore, the invention relates to the use of the electrochemical sodium metal halide secondary cell, the battery module, the system (AA), the battery kit and the energy storage system as a stationary energy storage system in or associated with charging stations for electric passenger cars and / or trucks and / or electric vehicles, electric aircraft and / or for storing volatile energy from wind turbines and / or solar cells and / or in military facilities or as an energy storage system in / on ships and / or military vehicles, such as tanks and / or aircraft carriers, vehicles, in particular rail vehicles, and / or electric trucks and / or electric vehicles and / or electric aircraft.

[0177] The invention is explained in more detail with reference to the following figures, without limiting the invention to these embodiments. Fig.1: Schematic diagram of a sodium nickel chloride secondary cell Fig. 2a.1, 2a.2, 2b.1, 2b2 and 2b.3: Representation of a secondary cell comprising the pantograph 3.2 as well as pantograph in cross-section, section AA and section BB Fig. 3a, Fig. 3b: Coupling of a container or filling aid 22 comprising secondary electrolyte with the filling area of ​​the current collector 3.2. Fig. 4a / 4b: Multi-part current collector 3.2 with substrate 6 and with holes 31 in the second area 11.2 and upper filling area with through hole 3.3.1 in the one-piece first area 11.1 and electrically conductive connection 11.3 Fig. 5: Battery module (A) with thermal start system 19 and connector plate 17 Fig. 6: System (AA) including support (B) as base part Fig. 7a and Fig. 7b: System (AA) with thermally insulated housing Fig.8: Mounting bracket for transporting the system (AA) Examples of implementation:

[0178] Determination of porosity: Methodology Mercury porosimetry: Test temperature: 23 °C (20 to 25 °C), start test pressure: 0.01 MPa (minimum), end test pressure: 400 MPa (maximum); pressure increase: 5 to 17 MPa / min, increase time: 80 min, pressure decrease: 8 to 35 MPa / min, decrease time: 50 min, total time: 130 min.

[0179] The porosity of the cathode granules is determined using the aforementioned method and is in the range of 11 to 14% for the aforementioned cathode granules.

[0180] The intergranular porosity can be determined using various methods: The density of the granules (toluene) is approximately 3.93 g / cm³. 3 The bulk density of the granules is 1.75 g / cm³. 3 The calculated open porosity according to DIN ISO 697 and EN ISO 60 is approximately 44.57%.

[0181] Determination of particle sizes: Device LS 13, Beckmann Coulter, USA, liquid dispersion in water or ethanol (depending on the solubility of the material), dispersion using ultrasound before measurement, evaluation model according to the Fraunhofer optical model.

[0182] β''-phase content: The Na-β''-aluminate phase content was determined by X-ray diffractometry. Sintered samples were milled (ball mill: 5 min at 30 Hz in MM 400 Retsch, Germany). Instrument: D8 Advance (Bruker (USA)): CuKα radiation; measurement in the angular range (2θ) from 5 to 80°. Measurements are generally performed at room temperature (23 °C). Quantitative evaluation of the measured values ​​was carried out using the Rietveld refinement method (software: Autoquan 2.8.0.2, XRD Eigenmann GmbH, Germany).

[0183] A separator according to the invention has a sodium β''-aluminate content of 87.56% ± 0.42% in the total sample. Other phases are sodium β-aluminate: 1.84% ± 0.30%, NaAlO2: 2.89% ± 0.33% and ZrO2 (cubic): 7.68% ± 0.17%.

[0184] Determination of ionic conductivity: Measurement using impedance spectroscopy (SP-420 instrument, Biologic, France, or 3000 AR, Gamry, USA). An amplitude of 10 mV is measured in a frequency range of 1 MHz to 9 Hz. Segments of sintered separator are cut for the measurement. Approximate dimensions: sample thickness (separator wall thickness) 1.7 mm, width 5.5 cm, and length 20 mm. The cross-sectional area was measured with a calibrated reflected-light microscope. The sample holder (an aluminum block) contains a glass fleece impregnated with a eutectic mixture of KNO3, NaNO3, and NaNO2 for contact purposes. The measurement is performed at a constant temperature in a drying oven. Table 1: Exemplary ionic sodium ion conductivity of a separator according to the invention: T [°C] 330 320 310 300 280,0 260 240 Ohm*cm 3,5 3,6 3,8 4,0 4,5 5,1 5,9 S / cm 0,288 0,276 0,262 0,249 0,224 0,197 0,168

[0185] Determination of thermal conductivity: Heat Flow Meter: Plate-based device typically used for quality control of insulation materials (FI-174-01 10 / 15) Fraunhofer for determining thermal conductivity (λ). Samples are positioned between heating and cooling plates. Under steady-state temperature conditions, a constant heat flow passes through the sample. The thermal conductivity is calculated from the electrical power, the mean temperature difference between the sample surfaces, and the sample dimensions. Samples are dried to constant mass before measurement. Measuring area 500 mm x 500 mm to 900 mm x 900 mm, DIN EN 12664, DIN EN 12667, DIN EN 674, and DIN 52612.

[0186] Determination of radial bending strength (Table 2): Device (Zwick 100, measuring head 2kN), load speed 1 mm / min, intermediate layer of the printing plates: paper Table 2: Mechanical properties of a hollow cylinder made of electrolyte (separator) Tensile strength σ[MPa] Bending moment [Nmm] Voltage [MPa] M F M0 M F M0 s F σ0 Outer diameter dA [mm] Length L [mm] Wall thickness dW [mm] (6 pieces, sodium β-aluminate, sintered: greater than 1550 °C) 44,7044,911,88 199 113 4923 to 6079 2810 to 3470 174.8 to 228.7 99.8 to 130.5 Outer diameter dA [mm] Length L [mm] Wall thickness dW [mm] (6 pieces, sodium β-aluminate, sintered: greater than 1550 °C) 44,5044,831,80 184 105 43834 to 4660 2188 to 2661

[0187] The mechanical strength of the electrolytes according to the radial bending pressure test on original sections sawn from an electrolyte tube, expressed as strength with a fracture probability of 63.21% due to brittle fracture behavior, is 208 MPa.

[0188] Fig.Figure 1 shows the schematic structure of a state-of-the-art sodium-nickel chloride secondary cell. The secondary cell has a negative electrode (-), a positive electrode (+), and a ceramic separator within a cell housing. The cathode comprises a salt and nickel. In the discharged state, virtually no metallic sodium is present (left secondary cell). In the charged state of the sodium-nickel chloride secondary cell, an anode of metallic sodium is formed, as shown in the right-hand secondary cell.

[0189] The Fig. Figures 2a.1, 2a.2 (enlarged section of 2a.1), 2b.1, 2b.2 to 2b.3 show a current collector 3.2 according to the invention in a secondary cell 0 with housing 1 and central axis of the housing 1.1. The separator 2 is located in the housing 1 ( Fig. 2a.2, 2c.1 / 2) having a separator wall 2.1 ( Fig.2a.1, 2c.3). Furthermore, the secondary cell 0 has a cathode 3, a cathode compartment 3.1 and the cathode-side current collector 3.2 in the cathode 3. The current collector is filled with cathode 12 ( Fig. 2a.1, 2a.2, 2c.1) comprising the cathode 3 and secondary electrolytes 7 (NaAlCl4).

[0190] Fig. Figures 2a.1 to 2c.3 show a secondary cell 0 with housing 1 in which a separator 2 ( Fig. 2a.2, 2c.2) with pantograph 3.2 is shown. In Fig. 2c.2 is in opening 3.9 is a substrate 6 ( Fig. 2a.1 / 2c). A planar element 8 is arranged around the outside of the separator 2 ( Fig. 2a.1, 2a.2, 2c.3) arranged, the diameter of which is flexible when the sodium anode 4 (anode, ) is charged during the charging of the secondary cell 0. Fig.2a.1, 2c.2, 2c.3) forms the element 8, allowing it to expand and form the anode space. The contact area 5.1 of the anode 5 in the anode space is hermetically sealed by an anode closure part 9 ( Fig. 2a.1, 2c.3). To position the planar element 8, a partially or fully circumferential groove 8.1 is introduced into the housing 0 ( Fig. 2a.1, 2c.3). Each secondary cell is hermetically sealed, in particular by means of an anode closure part 9 and cathode closure part 10, against moisture and gas ingress, especially air ingress ( Fig. 2a.1, 2c.2, 2c.3). A ceramic insulator ring, in particular an insulator joining ring, 13 ( Fig. 2a.1, 2c.3) is arranged electrically insulating between the cathode and anode on the separator.

[0191] The cathode-side current collector 3.2 has a lower cavity 14 extending into the cathode 3 ( Fig. 2a.1, 2c.1, 2c.3) having cylindrical area 3.4 ( Fig. 2b.1, 2b.2, 2c.3). The current collector 3.2 has a filling area 3.5 at the top and a contacting area 3.6 provided above the filling area. Below the filling area 3.5, a separation area 3.3 is provided, in particular comprising a pressed area as a separation area 3.7. The separation area 3.3 also has, according to Fig. 2b.5 / 6, and 2c.1 have two through-holes 3.3.1 through which the cathode 3 can be filled into the cathode chamber 3.1. Furthermore, the current collector 3.2 has a current collector side wall 3.8 and an opening 3.9 at the lower end of the current collector. The opening 3.9 of the current collector 3.2 can be provided at the lower end of the current collector 3.2 with a substrate 6, in particular a carbon-containing substrate 6, so that only liquid secondary electrolyte 7 can penetrate into the cavity 14 through the substrate 6 ( Fig. 2a.1, 2c.2, 2c.3).

[0192] In one embodiment, see Fig.In 2c.1, 2c.2, 2c.3, 3a, 3b, 4a and 4b, a current collector 3.2 is manufactured from two or more components, in this case a tube and a sheet bent into a tube. The components of the multi-part current collector are subsequently joined, in particular by a material bond, or the components are partially or completely coated. The components can be referred to as the first section, second section, or further section. This current collector is referred to as a multi-part current collector even if it is formed in one piece by the subsequent electrically conductive connection, in particular a material bond, and / or coating. A current collector formed from a tube by forming is a one-piece current collector 3.2, i.e., integrally formed from a single piece of material. Thus, the current collector can comprise a first section 11.1, which includes the filling section 3.5, the separating section 3.3, and the separation section 3.7 and optionally a transition area 15 adjoining the separation area below, and a second area 11.2 comprising the lower area 3.4 with current collector side wall, wherein the first and second areas are electrically connected to each other 11.3, in particular an electrically conductive connection 11.3 is formed between the first and second areas. In particular, the connection 11.3 is formed by material bonding, especially preferably by means of a nickel alloy and / or the first and second areas are coated with a nickel alloy.

[0193] In the filling area 3.5, the current collector has two through-holes 3.3.1 through which the cathode can be filled into the cathode compartment of the secondary cell without the cathode 3 entering the cavity 14 of the current collector 3.2. The cathode filling 12, comprising NaAlCl4, Ni / NiCl2, etc., is located in the cathode compartment 3.1.

[0194] After filling, the filling area 3.5 ( Fig. 2b.2, 2b.4, 2c.1) of the current collector 3.2 hermetically sealed, the secondary cell 0 is hermetically sealed gas- and moisture-tight by being fitted with a ceramic insulator connecting ring 13 ( Fig. 2a.1, 2c.3), which is provided with electrical insulation between the cathode and anode at the separator. The cathode is hermetically sealed with a cathode closure element 10. The anode is provided with a contact area 5.1, in particular comprising a metal disc, and is also sealed gas- and moisture-tight.

[0195] The electrical storage capacity of the secondary cell 0 is determined by the cathode space 3.1, filled with porous cathode 3, located between the outer wall of the current collector side wall 3.8 of the current collector 3.2 and the inner wall of the separator wall 2.1. Therefore, the diameter of the current collector 3.2 is particularly advantageously chosen to be between 8 mm and 20 mm when the diameter of the separator 2 is between 405 mm and 60 mm. The separator 2 has an integral separator wall 2.1 with an inner separator wall and an outer separator wall. The inner surface is considered the separator wall, and the outer surface of the separator 2 is considered the separator wall.

[0196] For high current withstand capability, the wall thickness of the current collector side wall 3.8 was adjusted to 5 mm to 10 mm, preferably from 0.5 to 3 mm. The most uniform current density distribution within the cathode chamber 3.2, which can be generated in a rotationally symmetrical separator 2, is achieved in this case by a current collector 3.2, which is also circular cylindrical and arranged centrally in the cathode chamber 3.1, in the form of a circular cylindrical tube or sheet metal formed into a tube, in particular a metal tube.

[0197] This current collector 3.2, in the form of a tube, can have a pressed separation zone of 0.1 to 5 mm in length as a pressed tube section, so that the filling area 3.5 remains above it. The cavity 14 formed below the separation zone 3.7 can remain free as a reservoir for the secondary electrolyte 7 below the pressed tube section 3.7.

[0198] The current collector 3.2, especially in tubular form, can optionally be pressed closed at the opening 3.9 at the lower end of the lowest section 3.4 either to such an extent that only the molten salt of the secondary electrolyte 7 can penetrate into the secondary electrolyte reservoir of the cavity 14, or the current collector in the metal tube is slightly pressed a few millimeters to centimeters above the opening 3.9 at the lower end of the lower section 3.4, so that a carbon felt 6 can be inserted as a substrate up to this stop and prevents the penetration of, for example, the cathode 3 filled in as granules.

[0199] In another embodiment, the carbon felt 6 is positioned up to the pressed tube section of the separation area 3.7, which is a few millimeters long, in the cavity 14 inside the pantograph 3.2, so that the carbon felt 6 protrudes from the cavity of the pantograph or is flush with it.

[0200] The lower section 3.4 of the current collector, in particular as a circular cylindrical lower section 3.4, preferably as a metal tube, must not have a closed surface. Instead, it must be ensured that the cavity 14, acting as a reservoir, is infiltrable with the secondary electrolyte 7 and that no granules of the cathode 3 can penetrate it. Therefore, micro-holes, as defined above, are also permissible, as long as no cathode can penetrate the cavity 14. These micro-holes can be round or slot-shaped holes in the current collector side wall 3.8, which prevent the cathode from penetrating the cavity 14. Micro-holes must not be formed in the filling area, as the secondary cell must be hermetically sealed to the outside against the ingress of air and / or moisture.

[0201] The current collector 3.2 can, in a further embodiment, be fitted with a substrate 6, in particular rolled-up carbon felt, before pressing the separation area 3.7, see below. Fig. 4.a and 4.b are filled to the point where they extend into the separation zone 3.7. Alternatively, the current collector can have a substrate 6 in the opening 3.9 at the lower end of the current collector 3.2. Optionally, the substrate 6 extends to the separation zone or terminates at any point within the cavity 14, particularly if the lower area extending into the cathode has no holes 31 or only microholes, and preferably the separation zone 3.7 is closed. The separation zone is considered closed if secondary electrolyte or components of the cathode or anode cannot pass through the separation zone. The cathode-side current collector 3.2 is preferably a nickel-plated copper tube and aligned collinearly with the axis of the separator 2.

[0202] The separator 2 divides the internal volume of the housing 1, which acts as an anode-side current collector, into an outer anode compartment 5.1, which in the charged state is filled with metallic sodium as the anode 5, and the inner cathode compartment 3.1, which is filled with granules of nickel / NaCl (uncharged state) or nickel / NiCl2 (fully charged state). The granules were filled into the cathode through the through-holes 11 of the filling area 3.5.

[0203] Furthermore, the cathode compartment 3.1 within the separator 2, which is a solid primary electrolyte made of sodium β-aluminate and has a high content of sodium β''-aluminate, is filled with a liquid secondary electrolyte, here consisting of sodium tetrachloroaluminate (NaAlCl4).

[0204] Fig.Figures 2a.1, 2c.1 to 2c.3, 3a, 3b, 4a and 4b also show a multi-part current collector 3.2 of the invention, which in the present case comprises a high-performance electrode comprising at least two sheets with different sheet thicknesses or at least one sheet and a tube. The current collector is filled with cathode 12 ( Fig.Figures 2a.1, 2a.2, and 2c.1 show the cathode 3 and secondary electrolytes 7 (NaAlCl4). The cathode fills the space between the separator and the current collector (electrode). The outer shape of the cathode 3 therefore corresponds to the inner shape of the separator 2, and the inner shape of the cathode corresponds to the outer shape of the current collector 3.2. It is variable and depends on these geometries of the separator. The current collector 3.2 comprises a filling area, a separation area 3.3, a cut-off area 3.7, and may have a transition area 15 and a lower area. The current collector 3.2 is multi-part; in particular, it comprises at least two sheets or, for example, a sheet and a tube, which are shown as the first area 11.1 and the second area 11.2. One sheet is, for example, formed to create the filling area, separation area, cut-off area, and optionally the transition area.This sheet can, for example, have a greater thickness of 0.5 to 33 mm, preferably 0.8 mm, optionally + / - 0.05 mm. The sheet thickness can be greater here because the cross-section of the electrode is reduced, firstly, by the through holes 3.3.1 (here called filling holes) introduced above the separation zone in the separation area, and secondly, the electrode cross-section can be reduced in the cathode area because the cathode contains a significant excess of nickel as an electronically conductive network and can take over part of the electron conduction.

[0205] The current collector 3.2, in particular in the form of a hollow body (in any conceivable cross-sectional geometry), especially a tube, can be manufactured from at least one sheet or from a monolithic component, e.g., extruded or seamless drawn. The area of ​​the formed sheet, in particular formed into a tube arranged within the cathode, can also deviate partially from a cylindrical or circular cylindrical tube shape by means of forming processes. Since a second sheet (11.2), in the form of, for example, a tube, is attached externally to the first sheet (11.1) of the current collector, in particular as part of the electrode, within the electrochemically active area, preferably in the area of ​​the cathode, an increase in surface area results compared to a one-piece tubular electrode, starting from the cross-section of the filling area 3.5 of the current collector 3.2. The second sheet advantageously has a homogeneous thickness.In another embodiment, the current collector can be manufactured from a homogeneous sheet thickness and widened in the area of ​​the cathodes, particularly the cathode chamber. This measure increases the diameter and reduces the sheet thickness, thus also increasing the electrode surface area. A reduction in the electrode sheet thickness due to an increase in the cross-section of the current collector compared to the filling area therefore leads to an increase in surface area. The current collector side wall can then advantageously have a thickness, particularly a sheet thickness, of 0.5 mm in the lower area of ​​the current collector, while the current collector side wall has a thickness of approximately 0.8 mm in the filling area, separation area, separation area, and optionally in the transition area. This can be achieved, for example, by a material-bonded connection such as welding, pressing, or soldering (if necessary).Also, as a single-step joining process during the glazing of the separator to the metal-ceramic composite, specifically encompassing the insulator joining ring and the contacting of the cathode-side current collector, crimped, fuel-locked connection of the current collector sections made of sheets and / or tubes, electron conduction can occur without significant contact resistance if appropriately designed. Additional elements that further increase the surface area of ​​the current collector are possible. The use of, for example, nickel-plated copper as a current collector, here the electrode, presents a challenge in welding and joining processes, insofar as the protective nickel layer is damaged by the joining process and oxygen from the air comes into contact with the copper, causing it to corrode.This effect can be counteracted by adapted joining processes or the subsequent application of protective layers, optionally under inert gas. When using at least two sheets to manufacture the current collector, the upper section exposed to air (which enables a hermetic seal of the Na-NiCl₂ cell) can be made of nickel, while the lower section of the current collector, located in the electrochemically active area (e.g., a pipe segment), can be made of nickel-plated copper, especially if the cell chemistry and charging voltages are adapted to these requirements. The charging voltage should then be chosen to be lower than the reaction potentials of the materials used. Furthermore, the welded copper tube or the tube formed from a copper sheet, which serves as the lower section of the current collector, can be provided with a protective layer, such as a nickel plating, after joining.Nickel coatings, or in general, should have a protective layer of at least 10 µm, preferably ≥ 50 µm, thickness.

[0206] Fig. 3a and Fig. Figure 3b shows a filling aid 22 mounted on a cathode-side current collector 3.2. The filling aid can contain the cathode, in particular in the form of granules, to facilitate filling it into the cathode compartment of the secondary cell (not shown, see Figure 3b). Fig. 2a) to be filled.

[0207] After an alternative ( Fig. 4a, Fig.4b) The current collector 3.2 can have at least one hole 31 below the separation area 3.7, in particular with a diameter larger than that of the microholes, if the cavity 14 is completely filled with substrate 6 and prevents the ingress of cathode 3. However, an alternative is preferred in which microholes as defined above can be present in the current collector side wall. The current collector has a first area 11.1, a second area 11.2, and an electrically conductive connection 11.3, in particular a metallurgical connection, between the first and second areas.

[0208] Fig.Figure 5 shows a battery module A with module frame 20 with power connections 21 and analog connections 24. Visible are the housings of the secondary cells 1 onto which a connector plate 17 with electrically conductive conductors 16 as cell connectors and with sensor cables 18 is mounted. A heating system 19, synonymous with thermal starting system 19, is arranged in the side wall of battery module A.

[0209] Fig. Figure 6 shows a system AA comprising five battery modules A on a support B as a carrier system. The lower structure C is shown. Fig. 7) of the support adapted so that the AA system can be picked up by a forklift. The support comprises a thermally insulated base with seal 26 onto which a thermally insulated housing 25 (see figure) is mounted. Fig.6a, sectional view) is mounted and forms a thermally insulated enclosure. The charging and / or data cable 23 is led out of an opening in the lower base part of the support B, in particular as a cable harness 27. The cables are preferably individually thermally insulated, as described above.

[0210] Fig. 7a and Fig. Figure 7b shows a thermally insulated housing 25 in the form of a hood (see Fig. 7a). In Fig. Figure 7b shows an arrangement 28 of systems AA in a holder 29. The holder has the dimensions of a standardized container, here referred to as a "Twenty-foot Equivalent Unit". The base structure 30 of the holder 29 is designed so that it can be picked up by the forks of a forklift truck (see Figure 7b). Fig. 8). Reference sign AA system comprising at least one battery module (A) A battery module (A) comprising an arrangement of electrochemical sodium metal halide secondary cells (0) B Support (carrier system) The structure of the support is adapted so that the support can be picked up by the forks of a forklift truck. 0 Electrochemical sodium metal halide secondary cell 1 Secondary cell housing 1.1 central axis of the housing 2 Separator 2.1 Separator wall, in particular comprising an inner separator wall and an outer separator wall 3 Cathode, in particular at least partially to completely filled cathode (3) made of a porous mixture of metal powder and metal halide powder or of granules containing these as well as cathode filling 3.3.1 Through hole(s) 3.1 Cathode space 3.2 Cathode-side current collector 3.3 Separation area, in particular the area above the pressed area (separation area) 3.4 lower area extending into the cathode (3), having a cavity, in particular a cylindrically shaped area, of the current collector side wall with inner wall and outer wall 3.5 Filling area 3.5.1 inner cavity in the upper filling area (3.5) with current collector side wall (3.8) of the current collector (3.2) 3.5.2 Filling opening Filling area 3.6 Contact area of ​​the cathode-side current collector 3.7 Separation zone, especially pressed zone 3.8 Current collector side wall 3.9 Opening at the lower end of the pantograph 4 Sodium (anode) 5 anode with anode compartment 5.1 Contact area of ​​the anode 6. Substrate, in particular carbon matrix, carbon felt 7 Secondary electrolyte 8 Shim or planar element 8.1 groove 9 Anode closure part 10 Cathode closure part 11.1 first area, 11.2 second area 11.3 electrically conductive connection, in particular material-bonded connection or material-bonded connection, 12 Cathode filling, in particular with secondary electrolyte (NaAlCl4, Ni, NiCl2, Ni / NaCl, NaF, Nal, etc.) 13. Ceramic insulator ring, in particular ceramic insulator joining ring 14 Cavity, in particular secondary electrolyte reservoir 15 Transition area 16 electrically conductive conductors (cell connectors) 17 Connector plate 18 sensor cables 19 thermal starting systems 20 module frames 21 Power connection 22 Filling aid 23 Charging and / or data port 24 analog connections 25 thermally insulated housing 26 Seal 27 Wiring harness 28 Arrangement of AA systems in a holder 29 29 Bracket, in particular with the dimensions of a standardized freight / sea container, such as a “Twenty-foot Equivalent Unit” 30 Base structure of the bracket 29 31 Hole, in particular with a diameter which is larger than that of the microholes, when substrate fills the cathode cavity.

Claims

[1] Electrochemical sodium metal halide secondary cell (0) comprising a housing (1) and a separator (2) arranged in the housing, which is permeable to sodium ions, wherein the separator has a separator wall (2.1) and a longitudinal central axis, wherein the separator (2) as a solid primary electrolyte separates an anode compartment (5.1) of an anode (5) from a cathode compartment (3.1) of a cathode (3), and - comprising a cathode (3) which at least partially or completely fills the cathode space (3.1) and is made of a mixture of metal powder and metal halide powder and / or of granules containing these, as well as - comprising a secondary electrolyte (7) of a sodium metal halide and / or a mixture of sodium metal halides, in particular as a liquid or as a solidified molten salt, wherein the secondary electrolyte (7) partially or completely fills the cathode compartment (3.1) and surrounds the cathode mixture as a matrix, and - has a metallic, cathode-side current collector (3.2) arranged in the cathode space (3.1), wherein the cathode-side current collector (3.2) has an upper filling area (3.5) with current collector side wall (3.8) and inner cavity (3.5.1) and optionally has a contacting area (3.6) of the cathode-side current collector (3.2) adjoining the filling area at the top, and - the current collector (3.2) has a lower cylindrical area (3.4) extending into the cathode with a current collector side wall (3.8) with a cavity (14), as well as - has a separation area (3.3) between the upper filling area (3.5) and the lower area (3.4), in particular wherein the separation area (3.3) is arranged above the cathode (3), and - wherein the separation area (3.3) has at least one through-hole (3.3.1), which connects the inner cavity (3.5.1) of the filling area with the cathode space (3.1), and - below the separating area (3.3) with at least one through-hole (3.3.1) the pantograph (3.2) has a separating area (3.7), - wherein the separation area (3.7) is not passable for the cathode (3), and, - wherein the current collector (3.2) in the lower area (3.4) extending into the cathode is designed with current collector side wall (3.8) with cavity (14) such that the cathode does not penetrate into the cavity (14) and the cavity (14) is accessible to the secondary electrolyte (7), characterized by , that the cavity in the lower area has a shell which is permeable to the secondary electrolyte and impermeable to the cathode. [2] Electrochemical sodium metal halide secondary cell (0) according to claim 1, characterized by, the cavity in the lower region, partially to completely contains a substrate (6) which is permeable to the secondary electrolyte and not permeable to the cathode. [3] Electrochemical sodium metal halide secondary cell (0) according to claim 1 or 2, characterized by , that the cathode consists of a mixture of metal powder and metal halide powder and / or of granules containing a composition selected from nickel, sodium halide(s), in particular sodium chloride and optionally sodium fluoride and / or sodium iodide or a mixture of sodium chloride, sodium iodide and sodium fluoride, and iron(II)S and optionally aluminium. [4] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 3, characterized by , that the cathode comprises a granulate, wherein the granulate has a particle size of 400 to 1500 micrometers. [5] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 4, characterized by , that the cavity in the lower region (3.4) of the current collector side wall (3.8) extending into the cathode (3), in particular in the lower end of the region (3.4) of the current collector side wall (3.8), has a substrate as a filter or membrane, in particular wherein the substrate closes the lower end of the cavity (14) or the cavity (14) against penetration of the cathode (3) and allows penetration of the secondary electrolyte (7), preferably molten secondary electrolyte, from the sodium metal halide salt melt. [6] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 5, characterized bythat the current collector (3.2) is multi-part, in particular the current collector comprises a first area (11.1) which includes the filling area, separation area (3.3) and separation area and optionally a transition area (15) adjoining the separation area below, and a second area (11.2) comprising the lower area (3.4) with current collector side wall, wherein the first and second areas of the multi-part current collector are electrically conductively connected to each other, in particular by means of a material bond, especially preferably by means of a nickel alloy, and / or the first and second areas are coated with a nickel alloy. [7] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 6, characterized by, comprising a housing (1) with a central axis (1.1), a sodium-ion-permeable separator (2) extending equidistantly to the housing (1) about the central axis (1.1) of the housing (1), which has an integral separator wall (2.1), wherein the separator, as a solid primary electrolyte, separates an anode compartment (5.1) of an anode (5) from a cathode compartment (3.1) of a cathode (3), and - a metallic cathode-side current collector (3.2) extending elongated in the cathode space (3.1) along the central axis (1.1) of the housing, in particular wherein the current collector is formed in one piece or in multiple parts, - wherein the current collector (3.2) has an upper cylindrical filling area (3.5) with current collector side wall (3.8) and inner cavity (3.5.1) and optionally a contacting area (3.6) of the cathode-side current collector (3.2) adjoining the filling area at the top, and the current collector has a lower cylindrical area (3.4) of the current collector side wall (3.8) extending into the cathode (3) and having a cavity (14), as well as a separating area (3.3) of the current collector side wall (3.8) formed between the upper filling area (3.5) and the lower area (3.4), - in particular wherein the separation area (3.3) is arranged above the cathode (3), - wherein the separating area (3.3) has at least one through-hole (3.3.1) and below the separating area with at least one through-hole (3.3.1) a separation area (3.7) is arranged which connects the inner cavity of the filling area (3.5) with the cathode space (3.1) via at least one through-hole (3.3.1), - wherein the separation area (3.7) is not passable for the cathode (3) and optionally the lower cylindrical area (3.4) of the current collector side wall extending into the cathode (3), which has a cavity (14), has a substrate, in particular a substrate permeable to the liquid secondary electrolyte. [8] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 7, characterized by, that the current collector (3.2) is made of a nickel alloy, in particular a nickel-iron alloy, with a nickel content of greater than or equal to 40 wt.%, in particular greater than or equal to 90 wt.% in relation to the total composition of 100 wt.% of the nickel-iron alloy. [9] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 8, characterized by , that the separator is made of a sodium β-aluminate, in particular comprising a content of zirconium dioxide and optionally a content of titanium dioxide, or is obtainable by reactive sintering from a pressed green compact comprising a powdered composition of 60 to 70 wt.% Al2O3, 10 to 20 wt% Na2CO3, 8 to 15 wt% LiAl5O8, 5 to 10 wt.% ZrO2 and optionally 0.01 to 5 wt.% TiO2 in relation to the total composition of 100 wt.% or from an aqueous composition of the aforementioned composition comprising water and optionally a film former, wherein the total composition of the aqueous composition is 100 wt.%. [10] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 9, characterized by , that the separator wall (2.1) has a sodium ion conductivity of greater than or equal to 0.2 S / cm at a temperature above 270 °C. [11] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 10, characterized by , that the cathode (3) a composition comprising as components 50 to 60 wt.% nickel, 30 to 40 wt% NaCl, up to 0.45 wt% aluminium, a content of up to 2.5 wt.% Fe(II)S, a content of up to 5 wt% nal and / or includes a content of up to 6 wt% NaF, the total composition is 100% by weight. [12] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 11, characterized by , that the molar ratio of sodium ions to metallic nickel in the overall composition of cathode and secondary electrolyte is from 1 : 1.8 to 1 : 10, in particular from 1 : 1.9 to 1 :

5. [13] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 12, characterized by that the separator is coated with a carbon-containing paste, in particular with a carbon-containing paste comprising graphite and carbon black and a binder, as well as mixtures thereof comprising further components, in particular a binder comprising sodium ions, preferably the binder is a mixture of sodium salts of polyphosphates. [14] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 13, characterized by , that the housing (1) is made of a metallic electrically conductive material and the housing has an anode closure part (9) on the top side and the sodium metal halide secondary cell has a contacting area (3.6) of the cathode-side current collector (3.2), wherein a ceramic insulator ring (13), in particular an insulator joining ring (13) with an electrically conductive contacting, in particular cylindrical contacting, for the contacting area (3.6) of the cathode-side current collector (3.2), electrically separates the cathode (3) and anode (5) from each other in a non-conductive manner. [15] Electrochemical sodium metal halide secondary cell (0) according to any one of claims 1 to 14, characterized by, that the secondary electrolyte (7) comprises a sodium metal halide comprising sodium aluminum chloride, in particular consisting of sodium aluminum chloride, in particular the secondary electrolyte is filled in liquid form into the electrochemical sodium metal halide secondary cell (0) via the contacting area (3.6) of the cathode-side current collector (3.2) and the subsequent separation area (3.3) through the at least one through-hole (3.3.1) and / or through the separation area (3.7) arranged below the at least one through-hole into the cathode compartment, - wherein the molten secondary electrolyte (7) penetrates into the cathode space (3.1) and / or into the cavity (14) of the lower area (3.4), in particular the cylindrically shaped area (3.4) with current collector side wall (3.8). [16] Battery module (A) comprising an arrangement of electrochemical sodium metal halide secondary cells (0) according to any one of claims 1 to 15, characterized by , that the secondary cells are electrically connected to electrically conductive conductors (16) at the respective contact areas (3.6) of the cathode-side current collectors and the respective contact area of ​​the anodes, in particular the secondary cells are connected in series at the contact areas (3.6) of the cathode-side current collectors and the contact area of ​​the anodes, or the secondary cells are connected in parallel and / or in series in groups, wherein the groups of secondary cells may in turn be connected in series and / or in parallel, and, wherein at least one electrically conductive conductor (16), in particular each electrically conductive conductor (16) or at least one electrical conductor (16) of each group of secondary cells, is connected to at least one sensor cable (18), and, wherein the battery module has at least one power connection. [17] Battery module (A) according to claim 16, characterized by, that the secondary cells at the contacting areas (3.6) of the cathode-side current collectors and the contacting area of ​​the anodes are each connected in series with electrically conductive conductors (16). [18] Battery module (A) according to claim 16 or 17, characterized by , that the electrically conductive conductors (16) are arranged as an arrangement of electrically conductive conductors (16), preferably as an arrangement on a connector plate (17), in particular are fixed, and in particular wherein at least one electrical conductor (16), preferably each electrically conductive conductor (16) or at least one electrical conductor (16) of each group of secondary cells is connected to at least one sensor cable (18). [19] System (AA) comprising a thermally insulated housing (25, AA.1) and at least one battery module arranged in the housing, in particular at least two battery modules, according to any one of claims 16 to 18, wherein the thermally insulated housing completely encloses the at least one battery module in a thermally insulating manner, and - optionally, the system comprising temperature sensor(s) with cable(s), in particular arranged in the space between the housing and battery module and / or on the outside of the thermally insulated housing, - comprising at least one wiring harness comprising power cables of the at least one battery module or power cables connected to the power terminals of the battery modules, and comprising the sensor cables, wherein preferably the wiring harness can be passed through or is passed through the housing. [20] System (AA) comprising a thermally insulated housing, characterized by , that the thermally insulated housing (25, AA.1) i) is closable with a support (B), preferably the support is a base part, and comprising at least one battery module, in particular at least two battery modules, according to one of claims 16 to 18, which is arranged on the support, in particular comprising a thermally insulated base part, wherein the housing is reversibly fixed on or to the support or is reversibly fixed, and, wherein the thermally insulated housing and the support completely enclose the at least one battery module in a thermally insulating manner, and / or ii) is closable with at least one thermally insulated element, in particular at least one side wall and / or bottom part and / or lid part or part of at least one of the parts, wherein the housing and the at least one element or part thereof completely enclose the at least one battery module and provide thermal insulation, and - optionally, the system comprising temperature sensor(s) with cable(s), in particular arranged in the space between the housing and battery module and / or on the outside of the thermally insulated housing, - comprising at least one wiring harness comprising power cables of the battery modules or power cables connected to the power terminals of the battery modules and comprising the sensor cables, wherein the wiring harness is preferably passable through or is passed through the support (B) as a base part. [21] Battery kit for energy storage, characterized by , that it comprises an arrangement of at least two systems (AA) according to claim 19 or 20, in particular as an arrangement in a container or a grid-shaped support. [22] Battery kit according to claim 21, characterized by that it serves to store electricity with an energy storage capacity of greater than or equal to 40 kWh, particularly in the electricity grid. [23] Battery kit according to one of claims 21 or 22, characterized by that the battery kit includes - at least one BMS (Battery Management System) optionally comprising modules, wherein the BMS is assigned at least one first processor or the BMS includes at least one first processor that is adapted to functionally control, analyze, transmit signals and / or regulate the BMS and modules of the BMS, - wherein the BMS includes at least one analog interface and / or at least one data interface, as well as at least one charge state balancing module for monitoring, charging and / or discharging control, which is connected to one to all secondary cells of one or more battery modules, - wherein the charge state balancing module is assigned at least one first processor for monitoring, charging and / or discharging control of the secondary cells, or the charge state balancing module includes at least one first processor adapted for functional analysis, signal forwarding, functional control and / or regulation of the monitoring, charging and / or discharging control of the charge state balancing module; optionally, the BMS also includes at least one state machine, clock generator, module(s) for monitoring the cell voltage and / or at least one multiplex. [24] Energy storage system comprising at least one battery kit according to any one of claims 21 to 23 and / or comprising at least one secondary cell according to any one of claims 1 to 15 and / or at least two battery modules (A) according to any one of claims 16 to 18 and / or comprising at least one system (AA) according to claim 19 or 20, and comprising - a processor orchestration level (POL) for the integration and functional control and regulation of the at least one BMS according to claim 23, which is assigned to the at least one battery kit, one or more secondary cells, a group of secondary cells, at least one battery module and / or at least one system (AA), and - for the functional control and regulation of AC / DC rectifier(s) and / or DC / AC inverter(s), each of which is independently assigned at least one first processor, or each independently comprising an AC / DC rectifier and / or a DC / AC inverter, which is adapted for the functional control and regulation of the AC / DC rectifier and / or the DC / AC inverter, and / or - for the functional control and regulation of DC / DC converter(s), in particular for charging and / or discharging the at least one battery kit, wherein at least one first processor is assigned to a DC / DC converter and / or a DC / DC converter comprises at least one first processor adapted for the functional control and regulation of the DC / DC converter, wherein the energy storage system is connectable or disconnectable and / or coupled to a network for the transmission and distribution of electronic energy, and - wherein, when the energy storage system is coupled with the network, the processor orchestration level (POL) functionally controls, monitors and / or regulates the injection of electrical energy from the energy storage system into the network for the transmission and distribution of electrical energy and / or functionally controls, monitors and / or regulates the extraction of electrical energy from a network for the transmission and distribution of electrical energy for the storage of electrical energy in the at least one energy storage system, or the processor orchestration level (POL) functionally controls, monitors and / or regulates the coupling and / or decoupling of the energy storage system with the network. [25] Use of the electrochemical sodium metal halide secondary cell according to any one of claims 1 to 15, the battery module according to any one of claims 16 to 18, the system according to claim 19 or 20, the battery kit according to any one of claims 21 to 23 and the energy storage system according to claim 24 as a stationary energy storage system, in particular as a stationary energy storage system in or in connection with charging stations for electric passenger cars, electrical industrial plants, electrical military plants and / or for storing volatile energy from wind turbines and / or solar cells or as an energy storage system in electric trucks, electric industrial trucks, electric vehicles, in particular industrial trucks and / or rail vehicles and / or on ships.

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