Power storage cell with adapted in-plane electrolyte pore flow resistance between anode and cathode

Abstract

The invention relates to a power storage cell designed as a lithium-ion storage cell or sodium-ion storage cell, comprising an anode, a cathode, a separator located between the anode and the cathode, and an electrolyte solution which is situated in pores of the anode, cathode and separator, wherein the ratio Rp,anode,in-plane / Rp,cathode,in-plane has a value in the range from 0.5 to 1.1, preferably in the range from 0.8 to 1.0, wherein Rp,anode,in-plane is the in-plane pore flow resistance for the electrolyte solution in the anode and corresponds to the quotient of the porosity of the anode and the in-plane permeability for the electrolyte solution in the anode, and Rp,cathode,in-plane is the in-plane pore flow resistance for the electrolyte solution in the cathode and corresponds to the quotient of the porosity of the cathode and the in-plane permeability for the electrolyte solution in the cathode. Such a power storage cell exhibits reduced aging compared to conventional power storage cells.

Description

[0001] Power storage cell with in-plane electrolyte pore flow resistance adjusted between anode and cathode

[0002] The present invention relates to a power storage cell with an in-plane electrolyte pore flow resistance adjusted between the anode and cathode. The present invention further relates to a use of the power storage cell and a method for selectively adjusting the ratio of the in-plane pore flow resistance for the electrolyte solution in the anode to the in-plane pore flow resistance for the electrolyte solution in the cathode.

[0003] In a power storage cell designed as a lithium-ion storage cell or a sodium-ion storage cell, ion transport between the anode and the cathode is enabled by an electrolyte solution comprising a lithium conducting salt or a sodium conducting salt and at least one solvent. This electrolyte solution is present in the pores of the anode and cathode, as well as in the pores of the separator located between the anode and the cathode. When filling a power storage cell with an electrolyte solution, the electrolyte solution is usually added in excess of the available pore volume in the power storage cell in order to obtain a power storage cell with high capacity and a long service life.A known mechanism for the aging of energy storage cells is the deposition of lithium at the anode, known as "lithium plating" in lithium-ion storage cells, or the deposition of sodium at the anode, known as "sodium plating" in sodium-ion storage cells. This deposition of metal at the anode leads to a rapid loss of the capacity of the energy storage cell. To prevent metal deposition at the anode, it is desirable to ensure, as best as possible, that the anode potential is not less than or equal to 0 volts compared to a Li / Li potential, especially during the charging process. + or Na / Na + Reference electrode becomes.

[0004] The object of the present invention is to provide a power storage cell, designed as a lithium-ion storage cell or sodium-ion storage cell, which is improved with respect to the above-mentioned disadvantages. A further object of the present invention is to specify a use of the power storage cell according to the invention for a rapid charging method. The present invention also relates to a method for the targeted adjustment of the ratio of in-plane pore flow resistance for the electrolyte solution in the anode R p , anode, in- P iane to in-plane pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- P iane .

[0005] One aspect of the present invention provides a power storage cell configured as a lithium-ion storage cell or as a sodium-ion storage cell. The power storage cell comprises an anode, a cathode, a separator located between the anode and the cathode, and an electrolyte solution present in the pores of the anode, cathode, and separator. The anode and the cathode have a ratio of in-plane pore flow resistance for the electrolyte solution in the anode Rp,anode,in-plane to in-plane pore flow resistance for the electrolyte solution in the cathode R P , cathode, in-piane in the range of 0.5 to 1.1, preferably in the range of 0.8 to 1.0.

[0006] The in-plane pore flow resistance for the electrolyte solution in the anode R p, anode, in-plane corresponds to the quotient of the anode porosity and the in-plane permeability for the electrolyte solution in the anode. Analogously, the in-plane pore flow resistance for the electrolyte solution in the cathode corresponds to R P , cathode, in-plane the quotient of porosity of the cathode and in-plane permeability for the electrolyte solution in the cathode.

[0007] The porosity n of the anode and the cathode can be calculated from the ratio of bulk volume Vbuik to skeleton volume V S kei can be calculated using the following formula:

[0008] The bulk volume can be determined based on the layer thickness and the electrode area. The layer thickness can be determined by measuring the thickness with a thickness gauge. The skeletal volume of the anode and cathode can be determined, for example, using helium pycnometry. To determine the skeletal volume, three independent measurements can be performed, and the average value calculated. To determine the bulk volume, three independent regions of the electrode with an area of, for example, 2 cm x 2 cm can be selected. Thickness measurements can be performed at 10 different points within each region, and the average value calculated.

[0009] The porosity of the anode and cathode refers to a formed storage cell, preferably at the time of delivery (“beginning of life” (BoL)), in which the storage cell has already been charged and discharged once after production, so that boundary layers form particularly on the anode and, to a lesser extent, also on the cathode. On the anode, this boundary layer is referred to in particular as SEI (solid electrolyte interphase) and on the cathode as CEI (cathode electrolyte interphase). During formation, an irreversible volume expansion of the electrodes occurs, in particular through the formation of the SEI or CEI and through a partial rearrangement of the particles, particularly in highly compressed electrodes. The porosity is determined at a state of charge (SOG) of the storage cell of 50%.

[0010] The permeability of the anode and cathode can be determined, for example, using flow simulation: Three-dimensional micro-computed tomography (CT) scans of the anode and cathode test volumes are taken. The particle geometries thus detected are subtracted from the test volume (the volume measured by the CT), thereby obtaining the geometry of the pore network. In a flow simulation, different flow velocities are applied, and the pressure increase across the test volume is calculated.

[0011] The relationship between flow velocity and pressure increase per length is described by Darcy's law:

[0012] Here, q is the flow velocity determined from the volume flow Q per cross-sectional area A, p is the dynamic viscosity of the fluid and k is the permeability.

[0013] With the permeability k and porosity n, the average pore flow velocity v can now be calculated. p of the fluid: q = nv p k Ap Vn

[0014] 1 ~ - np L

[0015] Expressed in terms of a pore flow resistance R p .

[0016] 1 Ap « -

[0017] PR p L

[0018] The pore flow resistance R p for a given fluid we then get:

[0019] The electrochemically active materials in the anode and the electrochemically active materials in the cathode do not expand evenly during the charging process. Rather, the electrochemically active materials in the anode often expand significantly more during the charging process than the electrochemically active materials in the cathode contract.

[0020] The porosity of the respective electrode changes due to the expansion of the electrochemically active materials in the anode and the contraction of the electrochemically active materials in the cathode during charging. When the electrochemically active materials of the anode and cathode expand together during the charging process, electrolyte is displaced from an electrode coil (jelly roll) or an electrode stack (stack). This occurs through electrolyte flow in the plane of the electrodes (in-plane).

[0021] The electrochemically active materials of the anode often have a rather flat, platelet-like particle shape, while the electrochemically active materials of the cathode generally have a more round, spherical particle shape. To achieve the high energy density required for the electrodes, the electrochemically active materials are usually compacted by calendering during electrode production. As outlined in Figure 12a, this compaction leads to an in-plane alignment of the platelet-shaped electrochemically active materials in the anode 2 due to the particle shape, and consequently to a comparatively low in-plane pore flow resistance for the electrolyte solution in the anode (R p, anode, in-plane). In contrast, the compaction at cathode 3 leads to an extension of the in-plane path length due to the round particle shape of the electrochemically active materials in the cathode and consequently to a comparatively high in-plane pore flow resistance for the electrolyte solution in the cathode (R p , cathode, in-plane). The inventors have determined with the aid of the flow simulation described herein that Rp, anode, in-plane, for example, has values ​​in the order of about 5 10 10 m -2 can have, whereas for R p , cathode, m- P For example, values ​​in the order of about 6 10 11 m -2This means that an anode can exhibit a pore flow resistance for the electrolyte solution that is approximately one order of magnitude lower than that of a cathode. This results in the electrolyte flow primarily occurring in the anode, and during the charging process, the electrolyte solution in the anode's pores is preferentially displaced.

[0022] During the charging process, cations of a conducting salt, i.e. lithium ions or sodium ions, are deposited in the electrochemically active materials of the anode. The deposition of the ions results in the electrolyte solution present in the pores of the anode having a conducting salt concentration that is lower than the originally used conducting salt concentration. As the inventors have discovered, this leads to the electrolyte solution displaced from the pores of the anode also having a conducting salt concentration that is lower than the originally used conducting salt concentration. As a result, different concentrations of the conducting salt can form in different areas of an electrode during extended operation of the storage cell after several charging and discharging processes.These different concentrations of conducting salt in the electrodes can lead to premature aging of the storage cell and, in particular, in the case of a lithium-ion storage cell, to the deposition of lithium and, in the case of a sodium-ion storage cell, to the deposition of sodium on the anodes.

[0023] These different concentrations of conducting salt can develop particularly when an excess of electrolyte solution is added compared to the available pore volume of the electrodes and separator, as is normally the case. In the case of an excess of electrolyte solution, particularly large amounts of electrolyte solution with reduced conducting salt concentrations compared to the original concentrations can be displaced from the anode during charging of the storage cell, as the inventors have discovered.

[0024] In order to reduce or prevent this, the Rp , anode, in- P iane and the R p , cathode, in- P iane are aligned. The ratio of R P , anode, in- P iane / R P , cathode, in- P iane is adjusted so that it has a value in the range of 0.5 to 1.1, preferably in the range of 0.8 to 1.0.

[0025] By reducing the difference between R P , anode, in- P iane and the R P , cathode, in- P This can ensure that, during the charging process of the storage cell, a similar amount of electrolyte solution with a reduced conducting salt concentration is displaced from the anode as electrolyte solution with an increased conducting salt concentration is displaced from the cathode. This reduces or prevents the formation of different conducting salt concentrations in different areas of the electrode.

[0026] The power storage cell can comprise an electrode coil or an electrode stack. The electrode coil or the electrode stack can be housed in a housing, wherein the electrode coil and the electrode stack comprise the above-described anode, cathode, and separator. The electrode coil or the electrode stack can extend in the housing along a longitudinal axis of the power storage cell. In an electrode coil, in particular a strip-shaped anode, a strip-shaped cathode, and a first strip-shaped separator located between the strip-shaped anode and the strip-shaped cathode, together with a second further strip-shaped separator, can be wound in layers around a winding core. In an electrode stack, individual anodes, cathodes, and separators located therebetween can be layered one on top of the other as plate-shaped elements.

[0027] Such power storage cells can achieve particularly high capacities.

[0028] Preferably, the electrode coil or the electrode stack has an extension of at least 3 cm along the longitudinal axis of the power storage cell. Power storage cells with such extensions along their longitudinal axis have particularly high capacities due to their size. Due to the ratio of R p , anode, in- P iane / R PIn the case of the cathode, the formation of different regions in the electrode with different concentrations of conductive salt along the longitudinal axis of the power storage cell occurs only to a minor extent or not at all. Due to the large extension of at least 3 cm along the main axis of the power storage cell, different concentrations of conductive salt along this main axis cannot normally be compensated by diffusion within a very short time during operation of the power storage cell and therefore lead to premature aging of the power storage cell.

[0029] Examples of energy storage cells with a length of at least 3 cm along the longitudinal axis include 18650 round cells with a length of 6.5 cm along the longitudinal axis. Other examples of energy storage cells with such a length are 4680 round cells with a length of 8 cm along the longitudinal axis, 4695 round cells with a length of 9.5 cm along the longitudinal axis, and 46120 round cells with a length of 12 cm along the longitudinal axis. Such energy storage cells can be used particularly in battery-electric vehicles.

[0030] The housing of the energy storage cell can be arranged circumferentially along the longitudinal axis around the circumference of the electrode coil or electrode stack. The housing can contact the main surfaces of the anode and cathode all the way around. The housing can circumferentially delimit the electrode stack or electrode coil. The housing can span the electrode stack or electrode coil. In particular, a separator layer can be present between the housing and the respective electrodes for electrical insulation. Such a housing, in which the electrodes or separators of the electrode coil or electrode stack are contacted by the housing, allows for a particularly compact design of the energy storage cells.

[0031] The housing can, in particular, comprise a metallic outer shell or a plastic outer shell. The housing can, in particular, be cylindrical, with poles for electrically contacting the power storage cell located at the opposite ends of the cylinder. The housing can also comprise a flexible foil, for example, made of aluminum, in which the electrode stack is firmly clamped. Such housings are used, for example, in pouch cells.

[0032] Since the electrode stack or the electrode coil is clamped in the housing, there is no room for the electrodes perpendicular to the longitudinal axis of the power storage cells to expand during charging of the power storage cell. In such power storage cells, conventional charging of the power storage cell with an excess of electrolyte solution therefore particularly easily leads to a displacement of the electrolyte solution from the electrode stack or electrode coil, thus leading to the formation of regions with different conducting salt concentrations during operation of the power storage cell. This problem can be avoided due to the ratio VOn R set according to the invention. p , anode, in-plane / Rp, cathode, in-plane P lane can be reduced or prevented.

[0033] In the power storage cell, the anode, the separator, and the cathode can have a first and a second edge region extending along the longitudinal axis, and a central region extending between the first and second edge regions along the longitudinal axis. The first edge region, the second edge region, and the central region located therebetween can each have the same extent along the longitudinal axis. Furthermore, the first edge region, the second edge region, and the central region located therebetween each have equal areas. The inventors have discovered that in conventional power storage cells, after several charging and discharging processes, the electrolyte solution in the pores of the first edge region, in the pores of the second edge region, and in the pores of the central region, for example the anode, have different concentrations of conductive salt.This can be achieved by adjusting the ratio of R according to the invention. P , anode, in- P iane / R P , cathode, in- P iane can be reduced or prevented.

[0034] In one embodiment of the power storage cell according to the invention, the power storage cell has, after at least 50 charging and discharging processes (C-rate during charging and discharging at least C / 2, SOC range 0-100% each, temperature 25 °C), after discharging to the cut-off voltage and resting for about 24 hours, an average concentration of Li in both the first and second edge regions. + or Na + in the electrolyte solution, which differs by a maximum of 30%, preferably by a maximum of 20%, more preferably by a maximum of 10% with respect to the original concentration of Li + or Na +in the electrolyte solution, ie at the point of delivery (BOL). The average C-rate can be determined in particular by the average values ​​of the C-rates occurring during charging over a period of 1 hour. Preferably, the power storage cell can be charged with the above-mentioned concentrations of Li + or Na + after at least 130 charging and discharging cycles.

[0035] In a further embodiment of the power storage cell according to the invention, the power storage cell has, after at least 50 charging and discharging processes (C-rate during charging and discharging at least C / 2, SOC range 0-100% each, temperature 25 °C), after discharging to the cut-off voltage and resting for about 24 hours, an average concentration of Li in both the first and the second edge region. + or Na +in the electrolyte solution, which differs by a maximum of 50%, preferably by a maximum of 40%, more preferably by a maximum of 20% in relation to the concentration of Li + or Na + in the electrolyte solution in the middle range. Preferably, the power storage cell can contain the above-mentioned concentrations of Li + or Na + after at least 130 charging and discharging cycles.

[0036] The anode can, in particular, comprise an electrochemically active anode material. An electrochemically active anode material is understood, in particular, to be a material capable of absorbing and releasing lithium ions if the power storage device is a lithium-ion power storage device, or of absorbing and releasing sodium ions if the power storage device is a sodium-ion power storage device. The electrochemically active material of the anode of the power storage cell can expand, in particular during the charging process, depending on the state of charge. This can be attributed, in particular, to the fact that the volume of the electrochemically active anode material increases during the charging process due to intercalation or alloying of lithium or sodium with the electrochemically active anode material, for example, graphite or silicon oxides, silicon, or mixtures thereof.In one embodiment, the volume of the electrochemically active anode material increases by 5% or more, by 10% or more, by 20% or more, by 40% or more, or by 100% or more during a charging process from 0% SOC to 50% SOC.

[0037] In particular, the electrochemically active anode material can be selected from a group consisting of: synthetic graphite, natural graphite, graphene, mesocarbon, doped carbon, hard carbon, soft carbon, fullerene, silicon-carbon composites, silicon, surface-coated silicon, silicon suboxide, silicon alloys, aluminum alloys, indium, tin alloys, cobalt alloys, and mixtures thereof. Preferably, the electrochemically active anode material can be selected from a group consisting of: graphite, silicon oxides, and silicon, or mixtures thereof. Such electrochemically active anode materials are particularly suitable for providing lithium-ion storage cells with high capacity.

[0038] In a sodium-ion storage cell, the anode can comprise an electrochemically active anode material. The electrochemically active anode material in a sodium-ion storage cell can be designed to absorb and release sodium ions during charging and discharging. The electrochemically active anode material in a sodium-ion storage cell can, in particular, comprise hard carbon, carbon, for example in the form of graphite, which, similar to a lithium-ion storage cell, can absorb and release sodium ions through intercalation. This can lead to an expansion of the electrochemically active anode material in the sodium-ion storage cell, similar to the lithium-ion storage cell.

[0039] The cathode can, in particular, comprise an electrochemically active cathode material. In a lithium-ion power storage cell, an electrochemically active cathode material is understood to mean, in particular, a cathode material capable of releasing and reabsorbing lithium ions during charging or discharging. In a lithium-ion power storage cell, the electrochemically active cathode material can be selected from a group consisting of: lithium transition metal oxides such as lithium cobalt oxide (UCOO2), lithium nickel cobalt manganese compounds (NCM or NCM),NMC), for example LiCoO2, LiNio,33Coo,33Mno,33O2, lithium nickel cobalt aluminum oxides (NCA), lithium olivines such as lithium iron phosphate (LFP), lithium spinels such as lithium manganese oxide spinel (LMO), lithium manganese nickel spinel (LNMO) or combinations thereof, further preferably wherein the electrochemically active cathode material is selected from a group consisting of: lithium nickel cobalt manganese compounds.

[0040] As cathode material, for example, materials containing sodium ions such as phosphates and diphosphates, for example sodium iron phosphates or compounds such as Na2 / 3Fei / 2Mni / 2O2 can be used in a sodium ion power storage cell.

[0041] In addition to the electrochemically active anode and cathode materials, the materials for the anode and cathode can also contain other materials, such as binders and conductive additives. Binders can include, for example, carboxymethylcellulose, polyvinylidene fluoride (PVDF), and / or polytetrafluoroethylene (PTFE).

[0042] The electrolyte solution for a power storage cell may comprise a lithium salt as a conductive salt and at least one organic solvent.

[0043] The electrolyte solution for a power storage cell may comprise a sodium salt as a conductive salt and at least one organic solvent.

[0044] In a lithium-ion power storage cell, the lithium salt can preferably be selected from a group consisting of: LiPFe, LiAsFe, UCIO4, ÜCF3SO3, lithium bis(trifluoromethylsulfonyl)amide or combinations thereof.

[0045] In a sodium ion power storage cell, the sodium salt may preferably be selected from a group consisting of: NaPFe, NaCIO4, Na-bis(trifluoromethane)sulfonimide, Na-bis(fluorosulfonyl)imide, Na-difluoro(oxalato)borate, Na-bis(oxalato)borate or combinations thereof.

[0046] The organic solvent may, in particular, comprise an organic polar solvent. The organic solvent may, in particular, be selected from a group consisting of: C2 to C4 cyclic esters of carbonic acid, for example propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, lactones, for example γ-, δ-, and ε-lactone, or combinations thereof.

[0047] The present invention also relates to a power storage cell designed as a lithium-ion storage cell or sodium-ion storage cell. The power storage cell comprises an anode, a cathode, a separator located between the anode and the cathode, and an electrolyte solution present in the pores of the anode, cathode, and separator. The anode contains an electrochemically active material that expands by at least 5%, preferably by at least 10%, more preferably by at least 40%, during a charging process from 0% SOC to 50% SOC, for example graphite, silicon oxide, silicon, or mixtures thereof. The power storage cell comprises an electrode coil or an electrode stack. The electrode coil or the electrode stack can be accommodated in a housing, wherein the electrode coil and the electrode stack comprise the above-described anode, cathode, and separator.The electrode coil or the electrode stack can extend in the housing along a longitudinal axis of the power storage cell. In the power storage cell, the anode, the separator and the cathode can have a first and a second edge region extending along the longitudinal axis and a central region extending between the first and the second edge region along the longitudinal axis. The first edge region, the second edge region and the central region located therebetween can each have the same extent along the longitudinal axis. After at least 50 charging and discharging processes (C rate during charging and discharging at least C / 2, SOC swing in each case 0-100%, temperature 25 °C), after discharging to the cut-off voltage and resting for approximately 24 hours, the power storage cell has an average concentration of Li+ or Li+ in both the first and second edge regions.Na+ in the electrolyte solution, which differs by a maximum of 50%, preferably by a maximum of 40%, more preferably by a maximum of 20%, with respect to the average concentration of Li+ or Na+ in the electrolyte solution in the middle range.

[0048] The present invention also relates to the use of an inventive power storage cell, as described above, for rapid charging. Rapid charging is defined as charging at an average C-rate of at least 1C. The C-rate is the ratio of the charging current of a power storage cell in amperes (A) to the capacity of the power storage cell in ampere-hours (Ah). Due to the ratio VOn R set according to the invention, p , anode, in-plane / Rp, cathode, in-plane P lane can inventive

[0049] Power storage cells can be charged particularly quickly using rapid charging methods without causing excessive aging of the power storage cells.

[0050] The present invention also relates to a method for adjusting a ratio of R p , anode, in- P iane / R P , cathode, in- P iane in the range of 0.5 to 1.1, preferably in the range of 0.8 to 1.0, in a current storage cell, wherein the adjustment of the ratio of R p , anode, in-plane / Rp, cathode, in-plane P lane PREFERABLY carried out by

[0051] (a) Increasing the pore flow resistance for the electrolyte solution in the anode R p , anode, in-plane and / or

[0052] (b) Reduction of the pore flow resistance for the electrolyte solution in the cathode R p , cathode, in-plane-

[0053] In the following, aspects of the present invention will be explained in more detail with reference to figures and exemplary embodiments. They show:

[0054] Figures 1a) to 1e) are schematic cross-sectional drawings of an anode and a cathode with exemplary conducting salt concentrations in the electrolyte solution during a charging process and a discharging process with the formation of regions of different conducting salt concentrations in the electrodes,

[0055] Figure 2 shows a graph with the different conducting salt concentrations in the edge regions and in a central region of the anode flanked by the edge regions,

[0056] Figure 3 shows a schematic top view of an unrolled anode after opening a current storage cell with the positioning of the samples in the first edge region, second edge region and in the middle region of the anode to determine a spatially resolved conductive salt concentration within the anode.

[0057] Figure 4 shows a graph with different courses of the conducting salt concentration in an edge region of the anode with a temporal course over a large number of charging and discharging cycles depending on the ratio of R p , anode, in- P iane / Rp, cathode, in-plane, Figure 5 shows a graph with different courses of the anode potential over a large number of charge and discharge cycles depending on the ratio of Rp, anode, in-plane / Rp, cathode, in-plane,

[0058] Figure 6 is a schematic cross-sectional drawing of a power storage cell with an electrode coil and electrolyte solution pressed out of the electrode coil,

[0059] Figure 7 shows a schematic cross-sectional drawing of an anode and a cathode with the flow direction “in-plane” and “through-plane”,

[0060] Figure 8 is a schematic plan view of an anode with barrier layers generated perpendicular to the in-plane axis,

[0061] Figure 9 is a schematic representation of an embodiment of the creation of barrier layers in the anode by locally applying a volume of barrier medium,

[0062] Figures 10a and 10b show a schematic representation of an embodiment of the production of barrier layers in the anode by locally applying a higher amount of anode material,

[0063] Figure 11a is a schematic plan view and Figure 11b is a schematic enlarged cross-sectional drawing of a cathode with microchannels generated in the direction of the in-plane axis,

[0064] Figure 12a is a schematic cross-sectional drawing of a conventional anode and cathode with in-plane aligned platelet-shaped electrochemically active anode material and spherical electrochemically active cathode material, Figure 12b is a schematic cross-sectional drawing of an anode and cathode according to the invention with platelet-shaped electrochemically active anode material and spherical electrochemically active cathode material aligned transversely to the in-plane direction, and Figure 12c is a schematic cross-sectional drawing of an anode and cathode according to the invention with in-plane aligned platelet-shaped electrochemically active anode material and in-plane aligned platelet-shaped electrochemically active cathode material.

[0065] In the following, elements with the same function are given the same reference symbols.

[0066] Figures 1a) to 1e) show schematic cross-sectional drawings of exemplary concentrations of the conducting salt in the electrolyte solution in the pores of the anode 2 and the pores of the cathode 3 of an electrode coil of a conventional lithium-ion energy storage cell prior to charging at a state of charge of 0%. The anode 2 and the cathode 3 are separated from each other by a separator layer 4. An excess of electrolyte solution containing a conducting salt was introduced into the lithium-ion energy storage cell compared to the available pore volume of the anode, the cathode, and the separator layer. Due to the excess of electrolyte solution, a small portion 27 of the electrolyte solution is already located outside the electrode coil. As shown in Figure 1a), the concentration of the conducting salt is 1 mol / l.The anode 2 has a first edge region 2A and a second edge region 2C at the respective poles of the lithium-ion storage cell, which flank a central region of the anode 2B located in the middle (poles not shown in Figures 1a) to 1e)). Analogously, the cathode 3 has a first edge region of the cathode 3A and a second edge region of the cathode 3C, which flank a central region of the cathode 3B. The respective edge regions and the central regions extend along a longitudinal axis 7 of the power storage cell 1. Before the start of the charging process, the concentration of the lithium conducting salt is 1 mol / l in all regions of the electrodes of the electrode coil and in the part 27 of the electrolyte solution located outside the electrode coil. A distance 26 perpendicular to the longitudinal axis 7 between the anode 2 and the cathode 3 across the separator layer 4 is normally a few hundred pm, for example 200 pm.In contrast, the anode 2, the cathode 3 and the separator 4 extend along the longitudinal axis 7 over a greater distance 25, which is usually at least a few centimeters, for example at least 3 cm.

[0067] During the rapid charging process, which is shown in Figure 1b), the volume of the electrochemically active anode material, for example, graphite, expands, as lithium is intercalated into the anode during the charging process. This expansion of the volume of the electrochemically active anode material causes the electrolyte solution contained in the pores of the anode to be displaced from the anode 2, as indicated by the arrows 5. Since Li is intercalated at the anode during the charging process, +is taken up from the electrolyte solution into the anode, the electrolyte solution present there is depleted in lithium conducting salt, the concentration being, for example, 0.5 mol / l, as shown in Figure 1b). As the inventors of the present invention were able to show, the electrolyte solution 6 displaced from the anode is therefore also depleted in lithium conducting salt and has a concentration of, for example, 0.5 mol / l. In particular, the electrolyte solution depleted in lithium conducting salt can be displaced from the electrode coil at both ends of the anode 2, so that the electrolyte solution 6 displaced at both ends of the electrode coil collects outside the electrode coil. In contrast, at the cathode 3, lithium ions are released from the electrochemically active cathode material, resulting in an increased concentration of lithium conducting salt in the electrolyte solution adjacent to the cathode.The concentration of lithium conducting salt there, for example, is 1.5 mol / l. Since the in-plane pore flow resistance for the electrolyte solution along the longitudinal axis 7 is smaller for the anode than for the cathode, and since the volume of the electrochemically active anode material increases first, the electrolyte solution 6 depleted of lithium conducting salt is predominantly displaced from the anode.

[0068] Figure 1c) shows the electrode coil with the anode 2 and the cathode 3 after completion of the charging process shown in Figure 1b) and after a rest period of at least one hour at a charge state of 100%. The concentration of lithium conducting salt in the anode 2 and in the cathode 3 has equalized again over the short distance 26 between the anode and cathode through diffusion and is slightly higher than the original lithium conducting salt concentration and is, for example, 1.1 mol / l. In contrast, the concentration of lithium conducting salt in the electrolyte solution 6 displaced from the electrode coil, as described in Figure 1b), is lower than the original conducting salt concentration and is, for example, approximately 0.5 mol / l.

[0069] Figure 1d) shows the discharge process of the lithium-ion storage cell after the rest period shown in Figure 1c). During the discharge process, the reverse processes occur compared to the charging process. In particular, the anode releases 2 Li + so that the concentration of lithium conducting salt increases adjacent to anode 2, while Li +from the electrolyte solution at the cathode 3 into the cathode, so that the lithium conducting salt concentration adjacent to the cathode 3 decreases. Since the volume of the electrochemically active anode material decreases during the discharge process, electrolyte 6 located outside the electrode coil can be drawn into the anode 2 at the same time during discharge, as indicated by the arrows 8. Since this electrolyte 6 located outside the electrode coil has only a low lithium conducting salt concentration, regions with different lithium conducting salt concentrations form along the longitudinal axis 7 over the distance 25. For example, the lithium conducting salt concentration in the first edge region 2A and in the second edge region 2B of the anode can be 1.2 mol / l, while in the central region 20 of the anode 2 it is 1.5 mol / l.

[0070] Figure 1e) shows the discharged lithium-ion power storage cell after at least 1 hour of rest at a state of charge of 0%. Due to the short distance 26 between the anode and cathode, the different lithium conducting salt concentrations have equalized horizontally to the longitudinal axis 7 through diffusion. However, due to the significantly larger distance 25, a conducting salt gradient exists along the longitudinal axis 7, with the first and second edge regions of the anode 2 and the cathode 3 each having lower conducting salt concentrations of, for example, 0.85 mol / l, while the central regions of the anode and cathode have increased conducting salt concentrations of, for example, 1.15 mol / l.

[0071] Depending on the size of the distance 25, the conducting salt concentration gradient built up along the longitudinal axis 7 may only equalize through diffusion after several days, or, at greater distances of 8 or 9 cm, as is the case with larger round cells, only within months. The uncharged lithium-ion power storage cell of Figure 1e) is then subjected to a charging process during normal operation, for example, a rapid charging process as shown in Figure 1b). As a result, with an increasing number of charge and discharge cycles, an increasing gradient of conducting salt concentration builds up along the longitudinal axis 7 in the conventional power storage cell. This increasing gradient of conducting salt concentration leads to accelerated aging of the power storage cell and can, in particular, also lead to lithium plating.

[0072] Figure 2 shows a graph with the experimentally determined lithium conducting salt concentrations along the longitudinal axis of a lithium-ion power storage cell in the anode of conventional power storage cells. The two graphs 12 and 13 show significantly different electrolyte concentrations in conventional power storage cells. The values ​​for graphs 12 and 13, designated by reference numerals 14 and 16, respectively, show the conducting salt concentrations in the first and second edge regions of the anode, while the values ​​designated by reference numeral 15 show the lithium conducting salt concentrations in the central region of the anode.

[0073] Figure 3 shows a schematic plan view of an unrolled anode 2 or cathode 3 after opening a power storage cell. The unrolled anode 2 can have a length of up to 2.5 m in the electrode coil of the power storage cell. Figure 3 also shows the distance 25 over which the first edge region 2A, the second edge region 2C, and the central region 2B of the anode 2 located therebetween extend. The width of the anode 2, the distance 25, can in particular be approximately 8 cm. In order to determine the different concentrations of the conductive salt, for example LiPFe, with spatial resolution along the distance 25, round samples 130A can be punched out from the first edge region 2A, as well as round samples 30B from the central region 2B, and round samples 130C of the anode from the second edge region 2C. Samples 130A, 130B, and 130C each have the same area.The solvent of the electrolyte solution, for example ethylene carbonate, can be determined from these samples using liquid chromatography / mass spectrometry (LC-MS). The amount of conducting salt can also be determined from the samples using ion chromatography. For the spatially resolved determination of the amount of conducting salt in the electrode coil, the cell is discharged to its lower cut-off voltage after cycling and left to rest for one day. The cell is then opened in an argon-filled glove box, the electrode coil is removed and unrolled approximately halfway. Round electrode samples (called "coins") are then taken using a hole punch (diameter e.g. 12 mm). Coins are taken from the outer areas in the first and second edge areas at a distance of approximately 1 to 2 mm from the edge of the electrode coating and from the middle of the electrode coating in the central area.Fifteen coins are taken from each area and each placed together in previously dried glass vessels. In principle, sampling can be performed in either the anode or the cathode, but sampling in the cathode is preferable as no falsification of the result due to SEI formation is to be expected. 5 mL of dried dimethyl carbonate (DMC) or acetonitrile (ACN) is then added to each coin as an extraction agent, and the glass vessels are tightly closed. The coins are left in the extraction agent for at least 16 hours, ideally on a shaker plate, to ensure complete extraction of the conducting salt. The conducting salt concentration in the extraction agent is then determined. The mean value of the conducting salt concentrations determined for the 15 individual coins is taken. For a relative comparison of the conducting salt amounts in the various positions, the ion chromatography results can be directly compared.

[0074] Figure 6 shows a schematic cross-section of a conventional lithium-ion storage cell 1 with a housing 20 that contacts the anodes 2 and the cathodes 3 of the electrode coil around the circumference. A mandrel 24 is located in the center of the electrode coil. The separator layer 4 is arranged between the anodes 2 and the cathodes 3. Due to the mechanically rigid housing 20, the electrode coil cannot expand perpendicular to the longitudinal axis 7 during charging of the storage cell 1. Due to this tension of the electrode coil in the housing, electrolyte solution 23 with a depleted concentration of lithium conducting salt is displaced from the electrode stack, particularly from the edge regions of the anodes, and collects above and below the electrode stack.The lithium-ion storage cell 1 further comprises poles 21 and 22, which are each electrically contacted by the current collector foils 18 of the anodes 2 or the current collector foils 19 of the cathodes 3.

[0075] Figure 7 shows a schematic cross-section of the sequence of layers in a conventional power storage cell, with anode current collector 29, anode 2, separator 4, cathode 3, and cathode current collector 34. “Through-plane” refers to the plane perpendicular to the main axis 7 and “in-plane” refers to the plane parallel to the main axis 7.

[0076] According to the invention, by specifically adjusting the ratio R P , anode, in- P iane / R P , cathode, in- PThis ensures that, during the charging process of the storage cell, a similar amount of electrolyte solution with reduced conducting salt concentrations is displaced from the anode as electrolyte solution with increased conducting salt concentrations is displaced from the cathode. This reduces or prevents the formation of different conducting salt concentrations in different areas of the electrode.

[0077] The ratio of R p , anode, in- P iane / R P , cathode, in-piane can be influenced by various measures, in particular by increasing the pore flow resistance for the electrolyte solution in the anode R P , anode, in- P iane, a reduction of the pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- P iane, or a combination of both measures.

[0078] The present invention therefore further relates to a method for adjusting the ratio of in-plane pore flow resistance for the electrolyte solution in the anode to in-plane pore flow resistance for the electrolyte solution in the cathode in a range from 0.5 to 1.1, preferably in the range from 0.8 to 1.0.

[0079] According to the invention, the ratio of R p , anode, in- P ia ne / R P , cathode, in- P lane is achieved by (a) increasing the pore flow resistance for the electrolyte solution in the anode R p , anode, in- P iane and / or (b) lowering the pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- P iane.

[0080] Increasing the pore flow resistance for the electrolyte solution in the anode R P ,anode,in- Plane can be achieved by creating one or more barrier layers in the anode vertically to the in-plane axis of the anode. Figure 8 shows an anode 2 with several barrier layers 28 and 28d vertically to the in-plane axis of the anode 2. The dashed line shows the center 28c of the anode 2 and the arrows show the flow direction of the electrolyte solution during the charging process. The barrier layer(s) 28 can be located at any position along the in-plane axis of the anode. The barrier layer(s) 28 can be located near the outer edges 28a, 28b and / or near the center 28c of the anode. In one embodiment, two barrier layers 28d are created, which are applied directly to the top and bottom edges of the anode. The barrier layers serve to reduce the pore flow resistance for the electrolyte solution in the anode R P ,anode,in- P lane and thus complicate the in-plane electrolyte flow in the anode.

[0081] The creation of barrier layers 28 can be achieved by various technical measures.

[0082] One possibility of creating barrier layers is shown in Figure 9. After

[0083] To coat a current collector 29 with an anode material mixture containing an electrochemically active anode material 30 to obtain a coated anode, a liquid mixture 31a is applied in stripes to the coated anode 2, which can seep into pores of the anode 2 and then harden to obtain barrier layers 28. The liquid mixture 31a can contain a sealing material and a liquid. The sealing material can, for example, be a polymer that is dissolved or dispersed in the liquid. The polymer can be a conventional binder, such as cellulose, cellulose derivatives, rubber, or thermoplastic fluoroplastics. The polymer can, in particular, be the same or a similar polymer to that which serves as a binder in the anode material. The liquid can, in particular, be water or an organic solvent.The application of the liquid mixture 31a to the coated anode 2 can take place before or after calendering the electrode. The application of the liquid mixture 31a to the coated anode 2 can be carried out, for example, using suitable nozzles.

[0084] If the barrier layer is applied directly to the upper and / or lower edge of the anode, ceramic materials, such as Al2O3, can also be used to create the barrier layers in addition to the polymer materials mentioned. Suitable materials include, in particular, those that can be used to produce coated separators and are described, for example, in US Pat. No. 9,647,254 B2.

[0085] Another possibility for producing barrier layers is shown in Figure 10. The application of barrier layers can be achieved by coating a current collector 29 with an anode material mixture containing an electrochemically active anode material 30, wherein the coating is carried out in such a way that an increased amount of anode material mixture is applied in stripes in regions 32a, compared to the surrounding regions. This leads to a higher loading (in mg / cm 2 After calendering 32b, the region 32c has a higher loading than the surrounding regions, while maintaining the same thickness. The resulting barrier layer 28 has a lower porosity than the surrounding regions. This leads to the desired increase in the pore flow resistance for the electrolyte solution in the anode Rp,anode,in-plane.

[0086] Alternatively, an anode material mixture with an increased binder content can be applied in areas 32a compared to the surrounding areas. After drying and calendering, the increased binder content leads locally to an increased pore flow resistance for the electrolyte solution in the anode R P , anode, in-plane. This option is advantageous because binders are already used in the anode production process. For the described creation of barrier layers during coating, multi-channel nozzles can be used, for example, which are capable of applying different materials and / or different amounts of material across the width of the nozzle. Alternatively, the desired strip-by-strip application of material can also be achieved using additional, separate individual nozzles.

[0087] Another possibility for producing barrier layers is shown in Figures 12a and 12b. As outlined in Figure 12a, the conventional manufacturing process for anodes 2 leads to an in-plane alignment of the platelet-shaped electrochemically active materials 30 and, consequently, to a short in-plane path length, indicated by arrow 40a. In contrast, the conventional manufacturing process for cathodes 3 leads to an extension of the in-plane path length, indicated by arrow 40b, due to the round particle shape of the electrochemically active materials 38a in the cathode. This results in a high flow in the anode, indicated by arrow 39a, and a lower in-plane pore flow resistance for the electrolyte solution in the anode (R P , anode, in- P iane) compared to a low flow in the cathode, indicated by arrow 39b and a higher in-plane pore flow resistance for the electrolyte solution in the cathode (R P, cathode, in- P iane). In comparison, Figure 12b shows an anode 2 in which the platelet-shaped electrochemically active materials 30 are not aligned in-plane, but rather have an angle in the range of approximately 70° to 110° relative to the in-plane direction. The rotated alignment leads to an increase in the in-plane path length, indicated by arrow 40c. This results in an equalization of the flux in the anode, indicated by arrows 39a, and an inventively optimized ratio of R P ,anode,in- P lane to R P , cathode, in- PAn advantageous rotated alignment of the platelet-shaped electrochemically active materials 30 in the anode can be achieved, for example, by a method in which a current collector is coated with an anode material containing platelet-shaped electrochemically active material to obtain a coated anode. After coating, the coated anode is exposed to a force field, so that the platelet-shaped electrochemically active material experiences a force through interaction with the force field, by which the platelet-shaped electrochemically active material is aligned relative to the field lines of the force field. This allows a partial alignment of the platelet-shaped electrochemically active materials 30 in the anode transverse to the main axis 7. Such a method is described, for example, in WO 2021 / 122348 A1. The platelet-shaped electrochemically active material 30 is preferably graphite.

[0088] Regardless of the method of their production, the width of the barrier layer(s) can have values ​​in

[0089] Range between 50 pm and 1 mm. The inventive reduction of the pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- P This can be achieved by creating one or more microchannels in the in-plane material. Figure 11a shows a cathode 3 with several in-plane microchannels 33. The dashed line shows the center 28e of the cathode 3 and the arrows indicate the flow direction of the electrolyte solution during the charging process. The microchannels serve to reduce the pore flow resistance for the electrolyte solution in the cathode R p , cathode, in- P iane and thus facilitate the in-plane electrolyte flow in the cathode.

[0090] The creation of microchannels can be achieved through various technical measures.

[0091] The microchannels can be created by mechanical ablation of cathode material. Alternatively, the microchannels can also be created by ablation of cathode material using a laser, as described, for example, in JB Habedank, Int. J. Adv. Manuf. Tech. 2019, 102, 2769-2778, doi: 10.1007 / s00170-019-03347-4.

[0092] The width 37b of a microchannel 33 is preferably as small as possible to lose as little active material as possible, and as large as necessary to achieve the desired effect on the pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- Pians. The microchannels 33 can have a width in the range of 10 pm to 40 pm, preferably in the range of 15 pm to 30 pm. The distance 37a between the microchannels is preferably as large as possible in order to lose as little active material as possible and as small as necessary to achieve the desired effect on the pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- P iane. The distance 37a between two parallel microchannels can be in the range of 1 mm to 10 mm, preferably in the range of 3 mm to 5 mm. The microchannels 33 can have a depth 36 corresponding to the thickness 35 of the cathode 3 without the current collector 34. Alternatively, the microchannels 33 can also have a shallow depth 37c.

[0093] Another possibility to reduce the pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- Piane is shown in Figure 12c. If platelet-shaped electrochemically active materials 38b are used for the production of the cathode instead of the conventionally used round electrochemically active materials 38a in the cathode 3 (Figure 12a), this leads to an in-plane alignment of the platelet-shaped electrochemically active materials 38b during the usual calendering. This results in a short in-plane path, indicated by the arrow 40a. This results in a reduction of the pore flow resistance for the electrolyte solution in the cathode R P , cathode, in- P iane, and thus an equalization of the flow in the anode and in the cathode, indicated by arrows 39a, and an inventively optimized

[0094] Ratio of R p , anode, in -plane / Rp, cathode, in-plane-

[0095] Example

[0096] The influence of in-plane pore flow resistance on the formation of an in-plane salt concentration gradient and the anode potential during battery cycling was derived using computer-aided simulations.

[0097] First, a flow simulation was carried out. For this purpose, a three-dimensional micro-CT scan was made of a conventional anode and a cathode, each covering an area of ​​approximately 70 pm 2The particle geometries thus detected were subtracted from the test volume (the volume measured by the CT). The result was the geometry of a pore network. From this, the in-plane permeability of the individual layers (anode, cathode) could be determined, taking into account the fluid dynamic properties of the electrolyte. For this purpose, different flow velocities were applied as part of the microstructure flow simulation, and the pressure increase across the test volume was calculated.

[0098] The in-plane permeability determined by flow simulation and the porosity values ​​measured by He-pycnometry resulted in the following values ​​for the in-plane pore flow resistance for the electrolyte solution in the anode and cathode, respectively:

[0099] In this case, the anode therefore has a pore flow resistance that is approximately one order of magnitude lower.

[0100] The subsequent battery cell simulations were performed in the Abaqus software (Dassault Systemes) using the Doyle-Fuller-Newman (DFN) approach on two-dimensional FEM models of the battery cell with coupling of electrochemistry and electrolyte flow (hereinafter referred to as DFN / electrolyte flow simulations). The battery cell was represented as a simplified "single layer" 2D model (i.e., a single sequence of the layers anode current collector 29, anode 2, separator 4, cathode 3, cathode current collector 34) (see Figure 7). Abaqus used the "fully coupled thermal-electrochemical-structural-pore pressure analysis."

[0101] During cell charging, the electrolyte is forced out at the top and bottom edges of the electrode coil and collects in a free volume between the current collectors, acting like an overflow reservoir (see Figure 6). During cell discharging, the electrolyte is drawn back into the electrode coil. It was assumed that all nodes of the model, with the exception of the aforementioned reservoir, are in fixed positions. This assumption is based on the fact that Li-ion cells are typically housed in a rigid housing or are subject to high external mechanical pressure, which is why the cell cannot deform outward. The volume change of the anode particles is therefore accompanied by a change in porosity and concomitant electrolyte movement.

[0102] The simulation was based on the following parameters:

[0103] Layer thickness:

[0104] • Anode: 70 pm

[0105] • Cathode: 50 pm

[0106] • Separator: 12 pm

[0107] Porosity (discharged cell):

[0108] • Anode: 0.3

[0109] • Cathode: 0.25

[0110] • Separator: 0.45

[0111] Volume expansion of the electrochemically active electrode materials:

[0112] • Anode particles: 13% volume change.

[0113] • Cathode particles: volume change assumed to be negligible.

[0114] Salt concentration in the electrolyte:

[0115] • 0.9 mol / l LiPF6

[0116] The results of the DFN / electrolyte flow simulations of the battery cell are shown in Figures 4 and 5.

[0117] Figure 4 shows, as a result of the DFN / electrolyte flow simulation, the course of the conducting salt concentration in an edge region of the anode over a period of more than 60 hours with a large number of charge and discharge cycles for ratios RP , anode, in- P iane / R P , cathode, in- P iane of 1.0 (solid line), 0.5 (dashed line) and 0.1 (dotted line). At the beginning of the charge and discharge cycles, in all three cases, an initial drop in the lithium conducting salt concentration is observed during charging of the power storage cell, followed by a rapid increase in the lithium conducting salt concentration in the anode during discharging of the power storage cell. It can be observed that for a ratio

[0118] R P ,Anode,in-plane / Rp, Cathode, in-plane of 0.1 (dotted line) with each charge and discharge cycle, the concentration of the lithium conducting salt in the edge area of ​​the anode successively from a concentration to below 200 mol / m 3 On the other hand, it can be seen that for a ratio R P,Anode,in-plane / Rp, Cathode, in-plane of 0.5 (dashed line) the concentration of the lithium conducting salt in the edge area of ​​the anode only to a concentration of about 500 mol / m 3 decreases. For a ratio R P , anode, in- P iane / R P , cathode, in-piane of 1 .0 (solid line) the concentration of the lithium conducting salt in the edge area of ​​the anode even remains constant.

[0119] Figure 5 shows the result of the DFN simulation with coupled fluid flow, the course of the anode potential over a large number of charge and discharge cycles for ratios R P , anode, in-plane / Rp, cathode, in-plane of 1.0 (solid line), 0.5 (dashed line) and 0.1 (dotted line). It can be observed that for a ratio

[0120] R P,Anode,in-plane / Rp, Cathode,in-plane of 0.1 (dotted line) with each charge and discharge cycle, the anode potential decreases from about 43 mV to about 35 mV. On the other hand, it can be seen that for a ratio R p , anode, in-plane / Rp, cathode, in-plane of 0.5 (dashed line) the anode potential only drops to a value of about 42 mV mol / m 3 decreases. For a ratio

[0121] Rp, anode, in-plane / Rp, cathode, in-plane of 1.0 (solid line) the anode potential even remains constant.

[0122] This shows that an undesirable decrease in the lithium conducting salt concentration in the edge region of the anode or an undesirable decrease in the anode potential can be prevented by adjusting the ratio R P , anode, in-piane / Rp, cathode, in-piane can be reduced or prevented.

[0123] The invention is not limited by the description based on the exemplary embodiments. Rather, the invention encompasses any novel feature and any combination of features, including, in particular, any combination of features in the patent claims, even if this feature or combination itself is not explicitly stated in the patent claims or exemplary embodiments.

Claims

Patent claims 1. A power storage cell, designed as a lithium-ion storage cell or sodium-ion storage cell, comprising an anode, a cathode, a separator located between the anode and the cathode, and an electrolyte solution arranged in pores of the anode, cathode, and separator, wherein the ratio of R p , anode, in- P iane / Rp, cathode, in-piane has a value in the range of 0.5 to 1.1, preferably in the range of 0.8 to 1.0, wherein R P , anode, in-piane is the in-plane pore flow resistance for the electrolyte solution in the anode and corresponds to the quotient of porosity of the anode and in-plane permeability for the electrolyte solution in the anode, and Rp, cathode, in-plane is the in-plane pore flow resistance for the electrolyte solution in the cathode and corresponds to the quotient of the porosity of the cathode and the in-plane permeability for the electrolyte solution in the cathode.

2. Power storage cell according to the preceding claim, wherein the anode comprises an electrochemically active anode material selected from a group consisting of: synthetic graphite, natural graphite, graphene, mesocarbon, doped carbon, hard carbon, soft carbon, fullerene, silicon-carbon composites, silicon, surface-coated silicon, silicon suboxide, silicon alloys, aluminum alloys, indium, tin alloys, cobalt alloys and mixtures thereof, further preferably wherein the electrochemically active anode material is selected from a group consisting of: graphite, silicon oxide and silicon and mixtures thereof.

3. Power storage cell according to one of the preceding claims, wherein the cathode comprises an electrochemically active cathode material selected from a group consisting of: lithium transition metal oxides such as lithium cobalt oxide (LiCoO2), lithium nickel cobalt manganese compounds (known by the abbreviation NCM or NMC), for example LiCoO2, LiNiO,33Coo,33Mno,33Q2, lithium nickel cobalt aluminum oxides (NCA), lithium olivines such as lithium iron phosphate (LFP), lithium spinels such as lithium manganese oxide spinel (LMO) or combinations thereof, further preferably wherein the electrochemically active cathode material is selected from a group consisting of: lithium nickel cobalt manganese compounds.

4. Power storage cell according to one of the preceding claims, wherein the electrolyte solution for a lithium-ion storage cell comprises a lithium salt as a conducting salt and at least one organic solvent and for a sodium-ion storage cell comprises a sodium salt as a conducting salt and at least one organic solvent, wherein the lithium salt is preferably selected from a group consisting of: LiPFe, LiAsFe, LiClCu, UCF3SO3, lithium bis(trifluoromethylsulfonyl)amide or combinations thereof, or the sodium salt is preferably selected from a group consisting of: NaPFe, NaClO4, Na bis(trifluoromethane)sulfonimide), Na bis(fluorosulfonyl)imide, Na difluoro(oxalato)borate), Na bis(oxalato)borate or combinations thereof;and / or wherein the organic solvent comprises an organic polar solvent, preferably wherein the organic solvent is selected from a group consisting of: C2 to C4 cyclic esters of carbonic acid, for example propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate lactones, for example γ-, δ- and ε-lactone or combinations thereof; 5. A power storage cell according to any one of the preceding claims, comprising an electrode coil or an electrode stack, wherein the electrode coil or the electrode stack is housed in a housing and comprises the anode, the cathode, the separator and the electrolyte solution, wherein the electrode coil or the electrode stack extends in the housing along a longitudinal axis of the power storage cell.

6. Power storage cell according to the preceding claim, wherein the electrode coil or the electrode stack has an extension of at least 3 cm along the longitudinal axis.

7. A power storage cell according to any one of the preceding claims, wherein the porosity of the anode and the cathode is determined by means of He pycnometry.

8. A power storage cell designed as a lithium-ion storage cell or sodium-ion storage cell, comprising an anode, a cathode, a separator located between the anode and the cathode, and an electrolyte solution arranged in pores of the anode, cathode, and separator, wherein the anode is a electrochemically active material that expands by at least 5% during a charging process from 0% SOC to 50% SOC, wherein the power storage cell comprises an electrode coil or an electrode stack, the electrode coil or the electrode stack is housed in a housing and comprises the anode, the cathode, the separator, and the electrolyte solution, wherein the electrode coil or the electrode stack extends in the housing along a longitudinal axis of the power storage cell, and the anode, the separator, and the cathode have a first and a second edge region extending along the longitudinal axis and a central region extending between the first and second edge regions along the longitudinal axis, characterized in that after at least 50 charging and discharging processes, after discharging to the cut-off voltage and resting for approximately 24 hours, the average concentration of Li in both the first and second edge regions.+ or Na + in the electrolyte solution by a maximum of 50%, preferably by a maximum of 40%, more preferably by a maximum of 20%, with respect to the average concentration of Li + or Na + in the electrolyte solution in the middle range.

9. Use of a power storage cell according to one of the preceding claims for rapid charging, wherein rapid charging is charging at an average C-rate of at least 1C, wherein C-rate is the ratio of the charging current of a power storage cell in amperes (A) to the capacity of the power storage cell in ampere-hours (Ah).

10. Procedure for setting a ratio of R p, anode, in-plane / Rp, cathode, in-plane in the range of 0.5 to 1.1, preferably in the range of 0.8 to 1.0, in a power storage cell, designed as a lithium-ion storage cell or sodium-ion storage cell, comprising an anode, a cathode, a separator located between the anode and the cathode and an electrolyte solution arranged in pores of the anode, cathode and separator, wherein R p , anode, in-piane is the in-plane pore flow resistance for the electrolyte solution in the anode and corresponds to the quotient of porosity of the anode and in-plane permeability for the electrolyte solution in the anode, and R P , cathode, in-piane is the in-plane pore flow resistance for the electrolyte solution in the cathode and corresponds to the quotient of the porosity of the cathode and the in-plane permeability for the electrolyte solution in the cathode.

11. Method according to the preceding claim, wherein the adjustment of the ratio of Rp, anode, in-plane / Rp, cathode, in-plane is carried out by (a) Increasing the pore flow resistance for the electrolyte solution in the anode Rp, anode, in-plane and / or (b) Reduction of the pore flow resistance for the electrolyte solution in the cathode Rp, cathode, in-plane- 12. Method according to the preceding claim, wherein increasing the pore flow resistance for the electrolyte solution in the anode R p , anode, m-piane is achieved by producing one or more barrier layers in the anode perpendicular to the main axis of the anode, wherein the one or more barrier layers are preferably produced by at least one measure selected from (a) coating a current collector with an anode material mixture containing an electrochemically active anode material, wherein the coating is carried out in such a way that (i) an increased amount of anode material mixture is applied in strips in selected areas compared to the surrounding areas, and / or (ii) an anode material mixture with an increased binder content is applied in strips in selected areas compared to the surrounding areas, (b) coating a current collector with an anode material mixture containing an electrochemically active anode material to obtain a coated anode, applying a liquid mixture comprising a sealing material and a liquid in strips and allowing it to seep into the coated anode, and then curing the sealing material by removing at least part of the solvent and / or by crosslinking the sealing material to obtain barrier layers in the anode, and (c) coating a current collector with an anode material containing platelet-shaped electrochemically active material, preferably platelet-shaped graphite, to obtain a coated anode, and at least partially aligning the platelet-shaped electrochemically active material in the coated anode transversely to the main axis of the anode by subjecting the coated anode to a force field.

13. Method according to the preceding claim, wherein the one or more barrier layers have a width in the range of 50 pm and 1 mm.

14. Method according to one of the preceding claims 11 to 13, wherein the reduction of the pore flow resistance for the electrolyte solution in the cathode R p , cathode, in-piane is achieved in which (1) one or more microchannels are created in-plane in the cathode, wherein the one or more microchannels are preferably created (a) by mechanical ablation of material of the cathode or (b) by ablation of material of the cathode using a laser and / or (2) Coating a current collector with a cathode material containing platelet-shaped electrochemically active material and subsequent calendering, wherein the platelet-shaped electrochemically active material is aligned in the cathode in the direction of the main axis of the cathode.

15. Method according to the preceding claim, wherein the microchannels have a width in the range of 10 pm to 40 pm and / or wherein the distance between two adjacent microchannels is in the range of 1 mm to 10 mm and / or wherein the microchannels have a depth which is in the range of 1 / 10 to 1 / 1 of the thickness of the cathode.

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