Battery device with improved thermal isolation

Abstract

The present invention relates to a battery device (10), particularly a battery device for use in electric vehicles, comprising two or more battery cells (12a, 12b), wherein a planar separating element (14) is arranged between at least two adjacent battery cells (12a, 12b), the planar separating element separating the battery cells (12a, 12b) at least partially separating them from each other, wherein the planar separating element (14) comprises: i) a core (16) comprising a first core layer (18), wherein 70% or more of the mass of the first core layer (18) is composed of porous amorphous silica relative to the mass of the core layer (18), and ii) a plastic casing (20) enclosing the core (16), the plastic casing comprising a plastic material.

Description

Technical Field

[0001] This invention relates to a battery device, particularly a battery device for use in electric vehicles, a method for manufacturing such a battery device, and a vehicle including the corresponding battery device. The use of specific planar separating elements for thermally is also disclosed. Background Technology

[0002] With increasing awareness of the need for sustainable management of fossil resources and the avoidance of greenhouse gas emissions, improving electric vehicles and developing new solutions for electric mobility have become increasingly important in many industrial sectors in recent years.

[0003] In many cases, a crucial component that significantly impacts the range of electric vehicles is the battery system used to store electrical energy; consequently, considerable research and development expenditure is invested in this area. Modern battery devices for electric vehicles mostly consist of multiple battery cells electrically connected to each other, in the form of so-called zellites or prismatic cells.

[0004] These battery cells include components of corresponding electrochemical cells within them, which are used for the electrochemical storage of energy.

[0005] For example, a single battery cell, which can be implemented in the form of a lithium-ion battery, is a chemically complex and relatively fault-prone system in which at least part of an exothermic reaction occurs during cycling. These battery cells are prone to failure, especially because they often contain flammable materials, particularly electrolytes, and can reach high temperatures during operation. Therefore, in the worst-case scenario, so-called thermal runaway can occur within a battery cell. During such thermal runaway, in addition to the potential pressure buildup within the battery cell, a significant temperature rise is often observed, which can even lead to fire.

[0006] Thermal runaway in a battery cell can potentially trigger a chain reaction, where the temperature rise of the failed cell disrupts the fragile balance of adjacent cells, also initiating thermal runaway in those adjacent cells. For these reasons, battery cells in corresponding battery devices are often separated from each other by separators, which in particular need to ensure the best possible thermal insulation between the cells in order to minimize or at least delay the chain reaction of thermal runaway in such situations.

[0007] However, because fire can also occur during thermal runaway, the separation element must, in most cases, also be fire-resistant so that it does not itself act as a combustible material and further promote a chain reaction in the event of a failure. Accordingly, the separation element should also be capable of providing fire-fighting isolation.

[0008] The requirements for the separator elements used vary depending on the construction method of the battery cell.

[0009] The challenge with pouch cells lies in their inherent volumetric changes, which are transmitted to the environment through the largely flexible casing of the cell. Many currently commercially available battery cells undergo this volumetric change in their pouch cell construction, particularly during charging and discharging—a process that occurs very frequently throughout the battery's lifespan, and especially during charging, on a relatively short timescale. This situation correspondingly places particular demands on the deformability of the separating elements or their ability to undergo reversible volumetric changes.

[0010] For prismatic cells, the volume change of the battery cell due to the cell casing is not a critical criterion in most cases, but this criterion must be considered when designing separator elements. However, prismatic cells are often more difficult to cool than pouch cells. Simultaneously, the casing of prismatic cells already occupies some structural space and increases their weight, which may negatively impact the energy density of the battery cell, but may also lead to higher manufacturing costs. Correspondingly, the following requirements are mainly placed on separator elements used for prismatic cells: these separator elements should have the best possible thermal insulation properties in the smallest possible construction space and allow for reliable fireproofing even with small thickness and low weight. Ideally, the cost of manufacturing the separator elements should be kept as low as possible to avoid excessively increasing the overall cost.

[0011] According to the inventors' estimates, the existing separators available for prismatic cells cannot satisfactorily resolve the existing conflicting objectives of: i) adequate isolation in terms of good thermal insulation and fire protection technology, ii) low weight and small space requirements, and iii) simple, rapid and cost-effective fabrication.

[0012] Furthermore, for many of the insulating elements known from the prior art, while attractive insulating effects have been measured at relatively low temperatures, significant and undesirable decreases in insulating effect have sometimes been observed at higher temperatures (i.e., even at those temperatures where thermal runaway may occur). Summary of the Invention

[0013] The purpose of this invention is to eliminate or at least mitigate the disadvantages of the prior art.

[0014] In particular, the present invention aims to provide a battery device in which battery cells are protected as well as possible from the effects of thermal runaway propagation by a separating element.

[0015] The object of this invention is to provide a battery device in which battery cells are thermally isolated from each other as well as possible by separating elements and protected from the effects of flames formed by surrounding battery cells by excellent fire-resistant isolation.

[0016] The premise of this invention in this respect is that the separator used can achieve an advantageous protective effect with a small thickness and a small weight, so as to realize the construction of a battery device with advantageous construction space requirements and a small weight.

[0017] In principle, an important objective of this invention is that the battery device and the separator used in this invention should be able to be manufactured in a particularly time-efficient and cost-effective manner.

[0018] Another object of the present invention is to provide a means of transportation that includes the battery device provided by the present invention.

[0019] Finally, a secondary objective of the present invention is to provide a use for thermally isolating two or more battery cells in a battery device.

[0020] The inventors of this invention have discovered that the aforementioned objective can be surprisingly achieved by providing a specific multilayer planar hybrid separator element in a battery device having two or more battery cells electrically connected to each other, as defined in the claims, wherein the separator element is implemented as a hybrid material, wherein a core element having a planar core layer based on amorphous silica is encased in a plastic shell. Here, a particularly advantageous result is achieved when a negative pressure is applied inside the plastic shell.

[0021] Surprisingly, the use of these planar separators in battery devices can advantageously resolve the conflict between, on the one hand, excellent thermal and fire-resistant technical isolation and on the other hand, low weight and minimal space requirements. Particularly advantageous is the quality of the solution to this conflict of objectives relative to advantageously low manufacturing costs, high availability of the required materials, and the time efficiency available for manufacturing the corresponding planar separators. In particular, the desired core layer can be obtained in a time- and cost-effective manner via pressing, whether by individual fabrication or by forming larger presses and subsequently separating the desired core layer into individual units. The desired encapsulation can also be produced efficiently, where, advantageously, simple equipment can be used for plastic lamination to achieve the desired encapsulation.

[0022] The aforementioned objectives are thus achieved by the subject matter of the invention as defined in the claims. Preferred embodiments of the invention are derived from the dependent claims and the detailed description below.

[0023] In particularly preferred embodiments, these embodiments (hereinafter referred to as preferred) are combined with features of other embodiments referred to as preferred embodiments. Therefore, combinations of two or more embodiments hereinafter referred to as particularly preferred are very particularly preferred. It is also preferred that an embodiment in which a feature referred to to a certain extent as preferred is combined with one or more other features referred to to a certain extent as preferred in other embodiments. The features of preferred vehicles, methods, and uses are derived from the features of preferred battery devices.

[0024] This invention relates to a battery device, particularly a battery device for use in electric vehicles, comprising two or more battery cells.

[0025] A planar separator element is arranged between at least two adjacent battery cells, the planar separator element at least partially separating the battery cells from each other, wherein the planar separator element comprises:

[0026] i) A component core, said component core comprising a first core layer, wherein, relative to the mass of said core layer, 70% or more by mass is composed of porous amorphous silicon dioxide.

[0027] ii) A plastic housing enclosing the component core, the plastic housing comprising a plastic material.

[0028] The battery device itself is generally well known in the art to those skilled in the art. The battery device according to the invention is particularly suitable for use in electric vehicles or their battery systems.

[0029] The significant advantages of the battery device according to the invention arise particularly from the specific design of the separating element. Accordingly, the battery device according to the invention is, in principle, unrestricted in terms of cell chemistry within the battery cell, wherein lithium-ion batteries are preferred due to their industrial importance.

[0030] In order to provide the necessary energy for electric vehicles, battery cells are often electrically connected to each other in the corresponding battery device, and the charging and discharging of the resulting cell stacks are often controlled by a battery control unit. Typically, for example, is a battery device according to the invention, in which battery cells are connected in parallel and / or series.

[0031] A typical battery device according to the invention is wherein the battery device is arranged in a housing, and / or wherein the battery device is surrounded by a protective cover.

[0032] Consistent with the understanding of those skilled in the art, the battery cells of the battery device according to the invention can be individual battery cells separated by separators, or battery packs consisting of multiple individual battery cells that are either not separated from each other or separated only by optional separators (e.g., made of silicone foam). However, for the safety of the resulting battery device, the inventors of the invention consider it particularly advantageous to use appropriate separators to separate individual battery cells or only battery cell pairs in each case. Thus, by way of example, in a battery device according to the invention, the battery cell comprises one battery cell or two or more battery cells electrically connected to each other, preferably comprising one battery cell.

[0033] In practice, the specific separating element of the present invention is particularly suitable for separating prismatic cells from one another. Correspondingly, a battery device according to the invention is preferred, wherein the battery cell is a prismatic cell or comprises prismatic cells, preferably prismatic cells. However, the inventors have found that when multilayer core layers are used in the separating element, especially when a structural material formed of thermoplastic elastomer is incorporated, as disclosed below, the separating element used according to the invention is also particularly suitable for use with pouch cells.

[0034] In practice, corresponding battery devices typically have multiple battery cells and a complementary number of separating elements. Therefore, the battery devices according to the present invention described below are also typical, wherein the battery device comprises four or more, preferably six or more battery cells electrically connected to each other, and / or wherein the battery device comprises three or more, preferably five or more planar separating elements.

[0035] Within the scope of this invention, the core layer is the main component of the planar hybrid material used as a separating element. This core layer comprises porous amorphous silica. Here, in the inventors' experiments, in addition to precipitated silica, also known as precipitated silica, fumed silica has proven to be particularly suitable. Correspondingly, a battery device according to the invention is preferred, wherein the porous amorphous silica is selected from the group consisting of precipitated silica, fumed silica, and silicate nanogels, preferably from the group consisting of precipitated silica and fumed silica, and particularly preferably fumed silica. Additionally or alternatively, a battery device according to the invention is preferred, wherein the porous amorphous silica is selected from the group consisting of particulate silica.

[0036] To optimize the isolation effect, the inventors suggest the use of particularly porous silica with a particularly large nitrogen surface area, which has proven to be especially efficient when acting with reduced pressure within the planar separator element. Therefore, a battery device according to the invention is preferred, wherein the porous amorphous silica has a surface area of ​​50 to 1200 μm. 2 Within the range of / g, preferably between 100 and 800 m 2 Within the range of / g, particularly preferred is 140 to 600m 2 Nitrogen surface area (BET) within the range of / g according to DIN ISO 9277:2014-01.

[0037] According to the inventors' estimates, besides porous amorphous silica, small amounts of other materials could theoretically be used in the core layer to adapt, for example, the physicochemical or mechanical properties of the core layer to the corresponding application requirements. However, in terms of cost-effective fabrication and simultaneously excellent insulation performance, the inventors believe it is preferable that the core layer be formed as substantially as possible from porous amorphous silica. For advantageous insulation performance and for fire-resistant properties, it is particularly advantageous to keep the proportion of any binder as low as possible. Accordingly, a battery device according to the invention is preferred in which 70% or more, preferably 80% or more, particularly preferably 90% or more, very particularly preferably 95% or more by mass of the first core layer is composed of porous amorphous silica. Additionally or alternatively, a battery device according to the invention is also preferred in which, relative to the mass of the first core layer, the first core layer comprises less than 5%, preferably less than 2%, particularly preferably less than 1%, very particularly preferably less than 0.5% by mass of binder, and especially no binder at all.

[0038] To further optimize the protection against thermal radiation, the inventors propose to provide a light-shielding agent in one layer of the element core, preferably in the first core layer, which can optimize optical absorption characteristics.

[0039] The inventors have achieved particularly advantageous results using a core layer with a specifically set thickness. Specifically, a preferred battery device according to the invention has a first core layer with a thickness of 200 to 450 kg / m³. 3 Within the range, preferably between 250 and 425 kg / m 3 Within a range, particularly preferred, is 300 to 400 kg / m³. 3 Average density within the range.

[0040] The first core layer significantly contributes to the overall insulation effect in the separator element to be used according to the invention, wherein, due to the inorganic material used, the first core layer advantageously possesses not only fire-resistant properties but also favorable thermal conductivity. Preferably, a battery device according to the invention is provided, wherein the planar separator element has an average total thermal conductivity of 0.050 W / mK or less, preferably 0.030 W / mK or less, particularly preferably 0.022 W / mK or less through the first core layer at 23°C, wherein the total thermal conductivity is determined according to DIN EN ISO 22007 2018. Additionally or alternatively, a battery device according to the invention is also preferred, wherein the planar separator element has an average total thermal conductivity of 0.060 W / mK or less, preferably 0.035 W / mK or less, particularly preferably 0.026 W / mK or less through the first core layer at 250°C, wherein the total thermal conductivity is determined according to DIN EN ISO 22007 2018.

[0041] The corresponding core layer can be advantageously obtained by pressing granular porous amorphous silica, wherein the use of binders can be advantageously omitted, which is particularly aided by the encapsulation with plastic material according to the invention, taking into account durability and stability. Therefore, a battery device according to the invention is preferred, wherein the first core layer is preferably prepared or can be prepared by pressing granular porous amorphous silica without the use of binders.

[0042] According to the invention, the element core and thus the first core layer are encased in a plastic shell. This encapsulation can be, for example, done with a curable plastic to obtain a thermosetting encapsulation. However, it is particularly preferred to use a thermoplastic material, taking into account the preparation of the separating element. In this context, a battery device according to the invention is preferred, wherein the plastic material comprises one or more thermoplastic and / or thermosetting plastics, preferably thermoplastic. In this respect, a battery device according to the invention is particularly preferred, wherein the plastic material comprises one or more plastics selected from the group consisting of silicone, polyolefins (especially polyethylene), polyamide, polyesters (especially polyethylene terephthalate), polyvinyl chloride, poly(meth)acrylates (especially polymethyl methacrylate), and melamine resin.

[0043] Even though it is at least theoretically conceivable to partially enclose the core element with the plastic material, it is preferred in almost all cases that the plastic casing be implemented as a substantially closed enclosure. Particularly preferred is that the core element be substantially form-fitted by the plastic casing, as can be done, for example, using a laminating apparatus. Therefore, for the vast majority of applications, a battery device according to the invention is preferred in which the plastic casing completely, preferably substantially form-fitted, encloses the core element. Additionally or alternatively, a battery device according to the invention is preferred in which the plastic casing forms an internal space in which the core element is preferably arranged substantially form-fittedly.

[0044] Starting from the aforementioned basic apparatus (which has already yielded excellent results in many cases and can be manufactured particularly efficiently in terms of time and cost), the inventors have identified two particularly preferred improvements that can further improve efficiency, especially under strong thermal loads, wherein these measures are combined with each other in a particularly advantageous design.

[0045] The first approach involves using a plastic casing with a highly porous filler to reduce internal pressure or even flush out the internal space. Smaller pressure reductions can be achieved, for example, by compressing the core element during thermal lamination and subsequently partially expanding it again, thereby achieving reduced internal pressure through cooling. Alternatively, the casing can be directly encapsulated under reduced pressure to ensure the lowest possible pressure within the internal space. According to the inventors, the appropriate pressure depends primarily on the intended application and the expected conditions. However, in general, the inventors consider these designs with relatively small negative pressures to be economically interesting, where, for example, a negative pressure of approximately 60 kPa can be achieved using conventional desktop vacuum equipment, as is known in part from the home sector. Accordingly, a battery device according to the invention is particularly preferred, wherein the separating element inside the plastic casing has a pressure of less than 100 kPa, preferably less than 75 kPa, particularly preferably less than 50 kPa, and very particularly preferably less than 25 kPa at 23°C. However, especially for demanding applications, a battery device according to the invention is preferred, wherein the separating element inside the plastic casing has a pressure of less than 100 Pa, preferably less than 10 Pa, particularly preferably less than 1 Pa, very particularly preferably less than 0.1 kPa, and particularly preferably less than 0.01 Pa at 23°C. As a particularly advantageous trade-off between isolation effect and manufacturing and handling costs, a battery device according to the invention is preferred, wherein the separating element inside the plastic casing has a pressure in the range of 1 to 95 kPa, preferably in the range of 5 to 90 kPa, particularly preferably in the range of 10 to 85 kPa, and very particularly preferably in the range of 20 to 80 kPa at 23°C.

[0046] A second advantageous measure is that, in addition to the first core layer, one or more, particularly preferably at least two, additional core layers are provided in the core element. This not only improves the overall isolation effect but also optimizes the deformation and damping characteristics, especially by using flexible materials, such as textile planar articles or structured elastomer materials, making the separating element more easily and reversibly deformable without damage and further protecting the prismatic cells in the battery compound against mechanical loads. Therefore, a battery device according to the invention is preferred, wherein the element core includes at least one second core layer, preferably a second core layer in contact with the first core layer, wherein the second core layer is selected from the group consisting of: elastomer planar materials, especially macroscopically structured elastomer planar materials, plastic foam, especially silicone foam, textile planar articles and textile spacer knitted fabrics, preferably textile planar articles, especially felt or nonwoven materials, and macroscopically structured planar materials formed of thermoplastic elastomers, especially silicone-based thermoplastic elastomers.

[0047] Regarding the thickness of the two core layers, a preferred battery device according to the invention is wherein the textile planar article has an average thickness in the range of 0.2 to 5.0 mm, preferably in the range of 0.5 to 3.0 mm, and particularly preferably in the range of 0.8 to 2.0 mm.

[0048] When selecting the textile planar article, the inventors considered certain design options to be particularly advantageous. First, a battery device according to the invention is preferred, wherein the textile planar article is a nonwoven material, preferably a mechanically bonded nonwoven material, particularly preferably a nonwoven material bonded by a combination of friction fits and form fits, particularly preferably a needle-punched nonwoven or a spunlace nonwoven, and especially preferably a needle-punched nonwoven.

[0049] Additionally or alternatively, a battery device according to the invention is preferred, wherein the textile flat article comprises one or more material fibers selected from non-flammable materials. A battery device according to the invention is particularly preferred, wherein the textile flat article comprises one or more material fibers selected from phenolic resin fibers, melamine resin fibers, and polyamide fibers, preferably from the group consisting of phenol-formaldehyde resin fibers and aromatic polyamide fibers, particularly preferably from the group consisting of phenol-formaldehyde resin fibers and para-aromatic polyamide fibers, wherein each of the respective fibers comprises 80% or more, preferably 90% or more, particularly preferably 95% or more by mass of the respective plastic.

[0050] In addition to the first core layer and particularly deformable materials, foil materials can also be used, which in particular provide additional fire resistance and shield against radiant heat. In this case, a battery device according to the invention is preferred, wherein the element core includes at least one third core layer, preferably a third core layer in contact with the first core layer, wherein the third core layer is selected from the group consisting of inorganic foils, preferably metal foils and mineral foils that optionally include a binder, preferably aluminum foils and layered silicate foils, especially clay silicate (sikalisilkat) foils.

[0051] The inventors have successfully identified particularly advantageous dimensions that allow for the acquisition of a separating element that can particularly advantageously resolve the conflict between the desired construction space and weight as one aspect and the desired isolation and fire-resistant properties as another. Specifically, a preferred embodiment of the battery device according to the invention is wherein the planar separating element has a size of 100 to 1000 cm on one of its planar sides. 2 Within the range, preferably between 120 and 650 cm 2 The area within the range. Additionally or alternatively, a battery device according to the invention is preferred, wherein the planar separator element has an average thickness in the range of 0.5 to 8.0 mm, preferably in the range of 1.0 to 6.0 mm. Additionally or alternatively, a battery device according to the invention is preferred, wherein the planar separator element has a thickness in the range of 50 to 2400 g / m². 2 Within the range, preferably between 100 and 1500 g / m 2 Within the range, and particularly preferred, is 200 to 1200 g / m³. 2 Average weight per unit area within the range.

[0052] Those skilled in the art will understand that in practice, the encapsulation is, in most cases, a relatively thin shell layer, and in many cases, also relatively thin compared to the core element. Therefore, a battery device according to the invention is particularly relevant to practice, wherein, relative to the volume of the planar separator element, the core element has a volume proportion of 50% or more, preferably 60% or more, particularly preferably 70% or more, very particularly preferably 80% or more, and / or wherein, relative to the volume of the planar separator element, the plastic shell has a volume proportion of 50% or less, preferably 40% or less, particularly preferably 30% or less, very particularly preferably 20% or less, in the planar separator element.

[0053] Those skilled in the art will understand that the core element, and especially the first core layer, in practice in most cases extends largely through the planar core element in order to achieve the desired isolation effect over most of the plane. Therefore, a battery device according to the invention is particularly relevant to practice, wherein the planar first core layer has an area on one of the planar sides corresponding to 80% or more, preferably 90% or more, particularly preferably 95% or more of the corresponding planar side of the entire planar separating element.

[0054] Relatedly, the use of a planar separator element for thermally is also disclosed, the planar separator element comprising:

[0055] i) A component core, said component core comprising a first core layer, wherein, relative to the mass of said core layer, 70% or more by mass is composed of porous amorphous silicon dioxide.

[0056] ii) A plastic housing enclosing the component core, the plastic housing comprising a plastic material.

[0057] As would be expected by those skilled in the art, the present invention also relates to a means of transportation comprising a battery device according to the invention.

[0058] The present invention also relates to an advantageous method for preparing the battery device according to claim 1, the method comprising the following steps:

[0059] a) Fabricating or providing the component core, the component core comprising the first core layer, and

[0060] b) Wrap the component core with plastic material to obtain the plastic casing.

[0061] The corresponding separator elements can then be arranged between the battery cells of the battery device.

[0062] Here, it is particularly preferred to prepare the element core or its first core layer by pressing silicon dioxide, wherein commonly used pressing molds can be used, provided that they can generate sufficient pressing pressure for pressing. Suitable pressing molds can be purchased from various suppliers. Correspondingly, a method according to the invention is particularly preferred, wherein, preferably in the case of using one or more binders, the preparation of the element core in step a) comprises pressing granular porous amorphous silicon dioxide.

[0063] The first core layer can, for example, be pressed directly in a mold, where it is intended for use in a later separator layer. However, alternatively, and in many cases more preferably in terms of process, a larger block can be prepared in advance, particularly by pressing as described above, from which the core layer of desired thickness is then separated into individual pieces. The corresponding original block can, for example, be a high-pressure pressed core layer with a thickness of 140 to 12000 cm. 2 A sheet of material of a certain area from which up to 100 individual core layers can then be prepared, for example. Therefore, in addition to or instead of preparation by means of pressing, a method according to the invention is particularly preferred, wherein preparing the element core in step a) of the method includes separating the first core layer from the original block material, preferably by means of a sawing unit or a cutting unit.

[0064] The method according to the invention is preferably used to prepare a separator element for preferred use in a preferred battery device. In addition to arranging other core layers on the first core layer before encasing the element core in plastic material, it is particularly preferred that the encasing is performed such that a negative pressure exists inside the casing.

[0065] Therefore, a method according to the invention is preferred in the first place, wherein preparing the element core in step a) comprises arranging the first core layer relative to a second core layer, wherein the second core layer is selected from the group consisting of: planar elastomeric materials, especially macrostructured planar elastomeric materials, plastic foams, especially silicone foams and planar textile articles, preferably planar textile articles, especially felt or nonwoven materials, and macrostructured planar materials formed of thermoplastic elastomers, especially silicone-based thermoplastic elastomers. Additionally or alternatively in this regard, a method according to the invention is preferred, wherein preparing the element core in step a) comprises arranging the first core layer relative to a third core layer, wherein the third core layer is selected from inorganic foils, preferably metal foils and mineral foils, optionally including an adhesive, preferably aluminum foil and layered silicate foils, especially clay silicate foils.

[0066] Additionally or alternatively, a method according to the invention is preferred, wherein the plastic material is wrapped around the element core under a pressure of less than 100 kPa, preferably less than 75 kPa, particularly preferably less than 50 kPa, and very particularly preferably less than 25 kPa. Additionally or alternatively, a method according to the invention is preferred, wherein the plastic material is wrapped around the element core under a pressure of less than 100 Pa, preferably less than 10 Pa, particularly preferably less than 1 Pa, very particularly preferably less than 0.1 Pa, and especially preferably less than 0.01 Pa. Here, a method according to the invention is particularly preferred, wherein the plastic material is wrapped around the element core in a laminating apparatus or sealing apparatus, preferably in a vacuum laminator.

[0067] The present invention and its preferred embodiments are illustrated and described in detail below with reference to the accompanying drawings. Attached Figure Description

[0068] Here, in the diagram:

[0069] Figure 1 A schematic cross-sectional view of a preferred battery device according to the invention is shown;

[0070] Figure 2 A schematic cross-sectional view is shown of a first particularly preferred planar separating element for a preferred battery device according to the invention;

[0071] Figure 3 A schematic cross-sectional view is shown of a second particularly preferred planar separating element for a preferred battery device according to the invention; and

[0072] Figure 4 A schematic cross-sectional view is shown of a third particularly preferred planar separating element for a preferred battery device according to the invention. Detailed Implementation

[0073] Figure 1 A simplified schematic cross-sectional view of a preferred battery device 10 according to the invention is shown. In the illustrated embodiment, two battery cells 12a, 12b are electrically connected to each other, wherein via... Figure 1 The battery control unit 24, schematically shown, performs battery management.

[0074] In the illustrated embodiment, battery cells 12a and 12b are lithium-ion battery cells, which are implemented in the form of prismatic cells. A planar separator 14 is arranged between battery cells 12a and 12b, which completely separates the two battery cells 12a and 12b from each other, so that there is no direct contact between the battery cells 12a and 12b.

[0075] Here, Figure 1 An exemplary segment is shown, which may be part of a larger battery device 10, which may include, for example, other battery cells 12a, 12b separated by planar separating elements 14, which are arranged together in a battery housing.

[0076] exist Figure 1 In the illustrated embodiment, the planar separator element 14 consists of an element core 16 and a plastic housing 20 that completely surrounds the element core 16, wherein the element core 16 occupies about 80% of the volume of the planar separator element 14 and extends over about 95% of the area of ​​the planar separator element 14.

[0077] exist Figure 1 In this embodiment, the component core 16 comprises a first core layer 18, which is composed of more than 98% by mass of fumed amorphous silica. The first core layer 18 is obtained beforehand from larger raw materials having the same basic composition, separated into individual units using a cutting device, together with other planar core layers. This raw material is prepared beforehand from powdered granular initial material by pressing in a high-pressure press without the use of a binder. In the illustrated embodiment, the first core layer 18 has approximately 350 kg / m³. 3 The average density.

[0078] Figure 1 The plastic casing 20 shown is composed of thermoplastic plastic, such as polyethylene terephthalate (PET). It is encapsulated using lamination equipment, wherein the element core 16 or the first core layer 18 is laminated between the PET foils, such that the element core 16 is substantially form-fitted and surrounded. Lamination is performed using a commercially available vacuum laminator, wherein a pressure of approximately 60 kPa is provided within the internal space of the plastic casing 20.

[0079] Figure 2 A simplified schematic cross-sectional view is shown through an alternative, particularly preferred planar dividing element 14, which can be used in... Figure 1 The battery device 10.

[0080] Figure 2 The planar separating element 14 is fabricated in principle as previously described; however, here a second core layer 22 is arranged on the first core layer before lamination. Figure 2 In the illustrated embodiment, the second core layer 22 is implemented as a macrostructured planar material formed of a silicone-based thermoplastic elastomer, which achieves enhanced deformability and improved absolute isolation properties through the planar separating element 14 through its structure and material properties. In addition to the second core layer 22, the first core layer (not shown) is covered on the opposite side with a thin layered silicate foil.

[0081] Figure 3 Showing from Figure 2 The planar separator element 14, based on the preferred construction, is particularly preferred and can also be particularly preferred for pouch cells. Figure 3 In the planar separator element 14, the element core includes two second core layers 22, which are located on both sides of the first core layer 18 to form side wings.

[0082] As Figure 3 Variations of the embodiments shown, Figure 4 It shows Figure 2 The alternative construction, namely the particularly preferred alternative planar separating element 14. In Figure 4In the planar separator element 14, the element core includes two first core layers 18, which are located on both sides of the second core layer 22 to form side wings.

[0083] Figure Labels

[0084] 10 Battery Device

[0085] 12a-b battery cell

[0086] 14 Planar Separating Elements

[0087] 16 component cores

[0088] 18 First Core Layer

[0089] 20 Plastic casing

[0090] 22 Second Core Layer

[0091] 24 Battery Control Unit

Claims

1. A battery device (10), particularly a battery device for use in electric vehicles, comprising two or more battery cells (12a, 12b). A planar separator (14) is arranged between at least two adjacent battery cells (12a, 12b), the planar separator separating the battery cells (12a, 12b) at least partially from each other, wherein the planar separator (14) comprises: i) Component core (16), the component core comprising a first core layer (18), wherein, relative to the mass of the core layer (18), the first core layer (18) comprises 70% or more of porous amorphous silicon dioxide. ii) A plastic casing (20) enclosing the component core (16), the plastic casing comprising a plastic material.

2. The battery device (10) according to claim 1, wherein the battery cell (12a, 12b) is a prismatic cell or includes prismatic cells.

3. The battery device (10) according to any one of claims 1 or 2, wherein the porous amorphous silica is selected from the group consisting of precipitated silica, fumed silica and silicate nanogels.

4. The battery device (10) according to any one of claims 1 to 3, wherein 80% or more by mass of the first core layer (18) is composed of porous amorphous silicon dioxide.

5. The battery device (10) according to any one of claims 1 to 4, wherein the plastic material comprises one or more thermoplastics.

6. The battery device (10) according to any one of claims 1 to 5, wherein the plastic housing (20) forms an internal space, and wherein the component core (16) is arranged in the internal space.

7. The battery device (10) according to any one of claims 1 to 6, wherein the separating element has a pressure of less than 100 kPa inside the plastic housing (20) at 23°C.

8. The battery device (10) according to any one of claims 1 to 7, wherein the element core (16) comprises at least one second core layer (22), wherein the second core layer (22) is selected from the group consisting of elastomeric planar materials, plastic foam, textile planar articles and spacer textiles.

9. A vehicle comprising an electric motor and at least one battery device (10) according to any one of claims 1 to 8.

10. A method for preparing a battery device (10) according to any one of claims 1 to 8, the method comprising the following steps: a) Prepare or provide the component core (16), the component core comprising the first core layer (18), and b) Wrap the component core (16) with plastic material to obtain the plastic casing (20).

11. The method according to claim 10, wherein preparing the element core (16) in step a) comprises pressing granular porous amorphous silicon dioxide.

12. The method according to any one of claims 10 or 11, wherein preparing the element core (16) in step a) of the method comprises separating a first core layer (18) from the original bulk material.

13. The method according to any one of claims 10 to 12, wherein preparing the element core (16) in step a) of the method comprises arranging the first core layer (18) relative to the second core layer (22), wherein the second core layer (22) is selected from the group consisting of elastomeric planar materials, plastic foams and textile planar articles.

14. The method according to any one of claims 10 to 13, wherein the encapsulation of the element core (16) with the plastic material is carried out in a laminating apparatus or a sealing apparatus.

15. The method according to any one of claims 10 to 14, wherein the element core is wrapped with the plastic material under a pressure of less than 100 kPa.

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