DE102012208314A1 - Electrochemical energy storage - Google Patents

Abstract

The present invention relates to an electrochemical energy store, in particular a lithium-ion battery, comprising a cell space (1) in which at least one anode, at least one cathode and an arranged between the anode and cathode electrolyte is disposed, wherein at least one with the at least one Anode connected to the current collector (2) and at least one connected to the at least one cathode current conductor (3) for tapping electrical energy is provided, and wherein at least one current collector (2, 3) a fluidisierbares material (5) is disposed between the and Inside the cell space (1) is provided a fluidic connection, and which fluidizes at a temperature which is at a defined limit, wherein the limit in a defined distance above an operating temperature of the at least one Stromableiters (2, 3). In such an energy storage thermal runaway can be particularly efficiently prevented, with no significant conversions of a conventional energy storage are necessary.

Description

The present invention relates to an electrochemical energy storage, in particular a lithium-ion battery.

State of the art

For lithium-ion batteries, such as lithium-sulfur batteries, as energy storage, it is known that they have very high energy content. This is advantageous for high power applications, however, it may result in thermal runaway in the event of an accident, for example. Such an event may occur, for example, when the temperature within the cell is so high that internal exothermic reactions further accelerate the formation of heat. This can lead to a dangerous condition of the battery. The safety of lithium-ion batteries can be particularly important in electric vehicles, which have particularly high capacities and thus high energy densities, which could lead to a high, in the event of an accident possibly released energy. To counteract this risk, it has hitherto been known to provide robust housings, safety valves, special separators, or flame-retardant additives in the electrolyte.

From the document DE 10 2008 008 483 A1 For example, a solid polymer electrolyte material for an electrochemical battery device is known. According to this document, thermal runaway is to be addressed by having the solid polymer electrolyte material at least one polymer having a microporous structure and a metal salt. In this case, a liquid-like lithium salt component is arranged at least in part of the microporous structure. According to this document, thermal runaway should thus be counteracted by the provision of a specially designed electrolyte.

The same applies to the document US 2009/0104523 A1 , Also in this document, a polymer electrolyte is described, which is intended to counteract thermal runaway. For this purpose, such a polymer electrolyte comprises a linear block copolymer, which is characterized by a block of a lithium-ion-conductive layer and another block with a specific elastic modulus.

From the document DE 10 2009 051 216 A1 Furthermore, an electrochemical energy store and a method for thermal stabilization of an electrochemical energy store, in particular a lithium-ion accumulator, known. Such an electrochemical energy store has at least one galvanic cell which contains a component or device which, at least locally exceeding a limit temperature in the interior of the galvanic cell, at least temporarily reduces the heat production inside the galvanic cell and / or at least temporarily increases the temperature Heat dissipation causes this cell to its environment. This can be realized, for example, by arranging a substance which disturbs the intended cell reaction within the galvanic cell.

Disclosure of the invention

The present invention is an electrochemical energy storage, in particular a lithium-ion battery, comprising a cell space in which at least one anode, at least one cathode and disposed between the anode and cathode electrolyte is disposed, wherein at least one connected to the at least one anode Current diverter and at least one connected to the at least one cathode current collector for tapping electrical energy is provided, and wherein at least one Stromableiter a fluidisable material is arranged, wherein between the fluidizable material and the interior of the cell space, a fluidic connection is provided, wherein the fluidisierbre material fluidized at a temperature which is at a defined limit, the limit being within a defined distance above an operating temperature of at least one of the current conductors.

In the context of the present invention, a lithium-ion battery can be understood as meaning, in particular, an at least partially lithium-based battery which uses lithium or lithium ions in the electrochemical process of its charging or discharging cycle. By way of example, a lithium-sulfur battery may be mentioned as a lithium-ion battery. Furthermore, the term battery can be understood in particular to mean a primary cell as well as a secondary cell, that is to say in particular a rechargeable accumulator.

Furthermore, in the context of the present invention, a cell space can be understood as meaning, in particular, an area of a particularly galvanic cell that is at least partially closed off from the external environment. In other words, in particular the actual electrochemical reaction of the energy store can take place in the cell space. For example, a cell space can be understood as the interior or the active areas of a cell coil.

Furthermore, a current conductor can be understood as meaning, in particular, an electrically conductive element connected to at least one electrode which can extend, for example, from the interior of the cell space into an area outside the cell space and optionally into a region outside a housing surrounding the cell space, and thus in particular for picking up electrical power Energy of the energy store can serve.

In the context of the present invention, a fluidisable material can furthermore be, in particular, a material or a substance that can be solid at room temperature or the operating temperature of the energy store or the current conductor, but can in particular form a fluid under temperature control. For example, such a material or such a substance may have a suitable melting point, for example in the case of at least partially crystalline polymers, or glass point, for example in the case of completely amorphous polymers, above which the material can form a fluid or become liquid. For the purposes of the present invention, the fluidization temperature, that is to say, for example, the melting point or the glass transition point, can be in particular in a range above the operating temperature of the energy store or of the current conductor. Thus, the fluidizable material, for example, be solid at the operating temperature and fluidize at a defined limit or form a fluid. A fluid may in particular be a substance which may be flowable.

An energy store according to the invention can in particular make it possible, for example, to be able to safely handle high energy contents, such as those which occur in a lithium-ion battery by providing highly energetic materials, at any time. In the case of such energy stores, for example at elevated temperatures, for example due to exothermic reactions of the high-energy substances, thermal runaway and further ignition of the battery may occur if no suitable countermeasures are taken. Such countermeasures can be realized in an energy storage device according to the invention in the case of heating of the cell or a short circuit in a particularly advantageous manner, in particular by a rapid suppression of the electrochemical reactions.

This can be achieved according to the invention in a prescribed energy storage, that at least one current collector a fluidizable material is disposed, between which and the interior of the cell space, a fluidic connection is provided, and which is fluidized at a temperature and therefore liquid or flowable, the at a defined limit value is, wherein the limit value lies within a defined distance above an operating temperature of the at least one Stromableiters.

In detail, can be exploited according to the invention, that in an energy storage, such as a lithium-ion battery, the current collector belong to the hottest positions, which are also heated very quickly. Therefore, the current conductors are suitable for detecting temperature peaks or an elevated temperature, which can indicate, for example, an impending thermal runaway, can be determined particularly well at a current conductor. According to the invention, a fluidizable material can be arranged on at least one current conductor, between which and the interior of the cell space, at least at a fluidization temperature of the fluidizable material, a fluidic connection is formed. The connection can be designed, for example, as an approximately lateral opening of the cell space towards the current conductors or to a region of the current conductors outside the cell space. As a result, the fluidisable material has free access to the interior of the cell space and, by fluidizing the fluidizable material in response to a defined elevated temperature, can further facilitate thermal stabilization of the energy store, as will be explained in detail later. For this purpose, the fluidization point of the fluidizable material, such as the melting point or the glass point, in particular at a temperature which is at a defined limit. This limit value can be above a working temperature of the at least one current conductor at a defined suitable distance. In other words, the fluidization point or the fluidization temperature of the fluidizable material is selected such that it is solid in a normal, intentional operation of the energy store and the usual heat generated in the interior of the energy storage, or not yet forms fluid. Only when a defined limit value of the temperature of the current collector is reached, which lies at a suitable distance from the operating temperature, the fluidisable material will fluidize and thus cause a thermal stabilization of the energy storage. The exact limit value or the exact fluidization temperature of the fluidizable material can be chosen in a suitable manner depending on the selected energy storage or the application of the energy storage. As a result, a thermal stabilization by fluidizing the fluidizable material can only take place in a suitable manner if it is ensured that a thermal runaway would take place or be safely imminent, with a suitable Temperature overhang or temperature buffer can be advantageous.

There are various ways to accomplish this task of thermal stabilization of the energy storage, as will be explained below. Basically, by fluidizing the fluidizable material allows a particular chemically inert material enters the cell space and there attenuates the running in the interior of the cell space electrochemical reaction or completely prevented, whereby the resulting temperature is lowered and thermal runaway can be prevented. For example, the fluidizable material in the fluid state itself flow into the cell space and thus prevent, for example, a flow of material or ion flow, which can bring the electrochemical reaction to a halt.

In this case, thermal stabilization can in particular mean a measure which can prevent, reduce or limit destruction or a different type of negative influence on the energy store, in particular by thermal runaway. Furthermore, thermal stabilization can be understood as the prevention of negative consequences of temperature peaks.

Within the scope of an embodiment, the fluidisable material can fluidize at a temperature which is in a range of greater than or equal to 100 ° C. to less than or equal to 200 ° C., in particular in a range of greater than or equal to 100 ° C. to less than or equal to 160 ° C. , lies. In this embodiment, it can be particularly ensured that, in particular for lithium-ion batteries, fluidization of the fluidizable material and thus initiation of the thermal stabilization during normal operation of the energy store does not take place, which can cause particularly reliable operation of the energy store. In addition, the fluidization temperature is low enough to initiate a thermal stabilization at a first sure sign of thermal runaway, so that the thermal stabilization is particularly safe and reliable possible. Thus, it can be ensured in this embodiment, in particular, that the energy storage operates safely and reliably in a normal operation, however, the risk to the environment can be safely reduced in a thermal runaway. In addition, a large number of materials are known which can be used as fluidizable materials in the context of this embodiment or in this temperature range.

Therefore, an energy store in this embodiment can also be produced particularly inexpensively.

In the context of a further embodiment, the fluidisable material can be arranged outside the cell space. In particular, the fluidisable material can be arranged completely outside the cell space. In this embodiment, the fluidizable material can thus be arranged such that a consequent influence on the electrochemical processes in the interior of the energy storage or in the cell space can be safely avoided. For example, neither the properties of the electrodes nor those of the electrolyte are adversely affected. Furthermore, the energy storage can be configured in a conventional manner, without requiring significant modifications, which also enables a particularly cost-effective production of the energy storage in this embodiment. Arranging outside the cell space may mean in particular that the fluidisable material from the interior of the cell space, such as from the electrodes, the electrolyte or the separator, may be at least partially separated by a suitable housing, wherein a fluidic connection between the fluidizable material and the interior of the cell space should be present. Furthermore, out-of-cell ordering may, in principle, mean local spacing from the active region of the cell, such as the active region of a cell coil.

Thus, it can be seen that in this embodiment can be brought as a further advantage that the fluidizable material, for example, when a corresponding, the cell coil and the current conductor surrounding housing is opened, can be visible and analyzable. As a result, it can be ensured at all times that the fluidisable material is not subject to age-related effects, so that safe working of the fluidizable material can always be present or can be checked. Furthermore, the fluidisable material can optionally be exchanged in a simple manner so as to be able to adapt the energy store to another field of application by adjusting the fluidization temperature of the fluidizable material. Therefore, a particularly large variety of applications of the energy storage is possible in this embodiment. As a further advantage, it can be seen that the fluidisable material is not exposed to the electrochemical processes during normal operation of the energy store. As a result, the fluidizable material can be particularly durable, which can make the energy storage even after prolonged use even more secure.

In a further embodiment, the fluidizable material may comprise an ionic liquid or a polymer. In this embodiment, the fluidizable material itself already be chemically inert and thus reach even into the interior of the cell space, so as to prevent, for example, the running inside the cell space exothermic electrochemical reaction. As a result, such a reaction or a transport of substances and / or ions necessary for such a reaction can be at least partly or at least locally suppressed, limited or completely prevented in the interior of the cell space or in the galvanic cell. Thereby, the release of further heat can be prevented, which causes a thermal stabilization of the energy storage. In this embodiment, therefore, the fluidizable material can be arranged in sufficient quantity on the current collector in order to thermally stabilize the energy storage can. The exact mass or amount of the fluidizable material can be easily selected by the person skilled in the art as a function of the exact design of the energy store, in particular the cell size or cell geometry. For example only, the selected amount or mass of the fluidizable material may be less than or equal to the amount or mass of the electrolyte. Examples of suitable ionic liquids include, for example, 1,2,3-trimethylimidazolium methyl sulfate, which has a melting point of 113 ° C. Examples of suitable polymers include, for example, thermoplastics. Specifically, polyethylene, polypropylene, polystyrene, polyacrylates or polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) or similar, in particular, chemically inert substances can be used purely by way of example. In principle, the fluidization temperature of polymers can be controlled in a manner understandable to the person skilled in the art via the molecular weight and / or the crystallinity.

In the context of the present invention, chemically inert can mean in particular a reaction inertness or inactivity towards components participating within the cell space and, in particular, in the electrochemical reaction of the energy store, preferably under the conditions possible in the interior of the cell space.

Within the scope of a further embodiment, the fluidisable material can be present embedded in a binder material. In this embodiment, influence can be taken on the flow behavior by a suitable choice of materials in a particularly simple and advantageous manner. Furthermore, in this embodiment, the adhesion of the fluid to the current conductor can be improved in a particularly advantageous manner. For example, the mixture may be applied by lamination. In this embodiment, suitable fluidisable materials may in particular comprise solids which are solid at room temperature, such as, for example, powders or ionic liquids, while suitable binder materials may in particular comprise polymers, such as polyethylene, polypropylene or other, in particular, thermoplastic polymers which are at a fluidization temperature or in a range of the latter can also be fluid or be. Embedding the fluidizable material in a binder material may in particular mean that the fluidisable material is at least partially surrounded by the binder material or adheres to it.

In a further embodiment, the fluidizable material may be formed as a coating of the current conductor. A coating is particularly simple and can be applied to the current collector by conventional methods, such as lamination, so that producing an energy store in this embodiment can be particularly simple. In addition, by a coating in particular a good and surface contact between the current collector and the fluidizable material can be prepared, so that when the occurrence of unwanted temperature peaks quickly and safely the fluidizable material can be liquid, especially in the cell space can pass, and so on can cause thermal stabilization. Furthermore, by varying the layer thickness of the coating or its extent, the existing fluidizable material or its quantity can be adapted to the corresponding energy store in a particularly simple manner, so that it can be ensured that a sufficient amount of fluidizable material for thermal stabilization can be present , Suitable layer thicknesses are in particular dependent on the energy store used and the size or geometry of the current conductor, wherein the coating thickness can essentially depend on the mass of the fluidizable material used. Particularly suitable fluidisable materials that can be used particularly advantageously as a coating include polyethylene and polypropylene or other thermoplastic polymers, as already explained above.

Within the scope of a further embodiment, the fluidisable material can form a container arranged on the current collector, in which a chemically inert fluid is arranged. In this embodiment, the fluidizable material can thus serve only as a casing or as an enclosure, which has or encloses a material that can enter the cell space and thus effect a thermal stabilization. In this embodiment, therefore, the fluidisable material will fluidize when a limit value of the temperature of the Stromableiters and thus the fluidization temperature of the fluidizable material is reached, and thus released the content. Particularly advantageously usable as a container are fluidisable materials, such as polyethylene or polypropylene or other thermoplastic materials, for example as described above. For example, the container may be formed as a plastic bag, which is mounted on the current conductor. In this embodiment, a particularly free choice of fluids flowing into the cell space can be selected. It can be seen that the substance arranged in the container can already be fluid or flow-shaped at room temperature or operating temperature of the current conductor, or only at elevated temperature, which may be the same or lower or possibly higher than the fluidization temperature of the container, fluid or can form a fluid. The term fluid with respect to the substance arranged in the container thus relates in particular to its state at the temperature of the fluidizing of the container or the desired activation temperature of the fluid. Furthermore, the container can completely or partially surround the fluid.

Furthermore, such a container can adhere to the current conductor in various ways. Non-limiting examples include, for example, mechanical bonding to a bonding agent, such as a staple or a plurality of staples, providing an adhesion promoter, such as carboxylic acid modified or anhydride modified polyolefins, between the container and the current collector or a bonding agent disposed on the underside of the receptacle. Depending on the material used for the container may already have the material of the container in itself sufficient adhesion properties.

In a further embodiment, the fluid arranged in the container may comprise an ionic liquid, an oil or a powder. Such substances can be particularly easily filled into a container, and can also safely cause a thermal stabilization, since they can easily enter the cell space and so reduce or prevent an electrochemical reaction by their chemical inertness. Examples of suitable ionic liquids include, purely by way of example, 1-butyl-3-methylimidazolium trifluoromethanesulfonate (BMIM Otf) having a melting point of 16 ° C. or 1-butyl-1-methylpyrrolidinium-bis (trifluoromethylsulfonyl) -imide (BMPyrr NTf2) having a melting point of -18 ° C, whereas examples of an oil may include, in particular, high melting or high boiling oils, such as silicone oils or paraffin oils, such as paraffin oils containing chlorine. Suitable powders further include, for example, silica, alumina or titania. For example, the fluids or even the fluid which is arranged in the container can have a fluidization point corresponding to the fluidisable material of the container. As a result, even if the container is damaged, it can be prevented that the fluid, in particular if it is a fusible fluid which is solid at room temperature or the operating temperature of the energy store, or which significantly changes its viscosity at elevated temperature, moves away from the current conductor, and then no longer available for thermal stabilization. For the purely exemplary case, that the fluid arranged in the container is also a fluidisable substance, which fluidizes above the operating temperature of the current collector, can, as stated above, be dispensed with the provision of the container.

In the context of a further embodiment, at least one fluid polymerizable monomer can be arranged in the container. In this embodiment, therefore, a substantially fluid monomer can reach the interior of the cell space and polymerize there, for example, by the resulting heat. By means of a polymerization step directly in the interior of the cell space, a material flow or an ion flow can be reduced particularly effectively and thus a thermal runaway can be prevented particularly reliably. In this embodiment, it is obvious to the person skilled in the art that chemically inert sense of the present invention, as already described, can in particular mean a reaction inertness to components participating within the cell space and in particular to the electrochemical reaction of the energy store. A reaction of the monomer with one another, optionally in addition to an approximately necessary polymerization catalyst, is included in the meaning of the invention of the term chemically inert. Examples of fluid polymerizable monomers include, for example, styrene, divinylbenzene or acrylates.

In the context of a further embodiment, at least one guide device for guiding a fluid into the interior of the cell space can be provided on at least one current conductor. The guide device can serve, for example, to direct the fluidizable material and / or the fluid arranged in a container into the interior of the cell space. For this purpose, the fluid can for example be directed or guided to an opening of the cell space. In this embodiment, it can be realized with particular certainty that the fluid reaches the interior of the cell space in order to effect a thermal stabilization. A loss of fluid due to a flow to an unintentional Position outside of the cell space can thus be avoided.

In this case, the at least one guide device can be configured in particular as a guide rail. This can for example be designed in one piece with the current conductor or be attached by suitable fastening means or by gluing on the current conductor. This is a particularly simple and cost-effective embodiment, in order to effect a safe guiding of the fluid into the interior of the cell space. A guide such as a guide rail can be configured for example from a plastic or metal, wherein the guide should be fixed above the fluidization temperature of the fluidizable material.

In a further embodiment, the fluidizable material may be present together with at least one flame-retardant substance. In this embodiment, thus not only the electrochemical reaction can be prevented, and thus a further thermal runaway be prevented, but it can also be responded to that possibly even negative consequences, such as in particular flame formation has occurred. Furthermore, the flame formation can be suppressed, so that even when reaching very high temperatures, flame formation is reduced or prevented, which offers a further safety advantage. The flame-retardant substances may, for example, be finely distributed in the chemically inert fluid arranged in the container. Suitable examples of flame retardant substances include, for example, phosphorus compounds such as trimethyl phosphate, triethyl phosphate.

Drawings and examples

Further advantages and advantageous embodiments of the subject invention are illustrated by the drawings and explained in the following description. It should be noted that the drawings have only descriptive character and are not intended to limit the invention in any way. Show it

1 a schematic representation of an embodiment of an energy storage device according to the invention;

2 a schematic representation of the embodiment of 1 in an embodiment;

3 a schematic representation of the embodiment of 1 in a further embodiment;

4 a schematic representation of the embodiment of 1 in a further embodiment;

5a a schematic representation of the embodiment of 1 in a further embodiment;

5b the embodiment according to 5a in a 90 ° offset side view;

6 a schematic representation of the embodiment of 1 in a further embodiment

7 a schematic representation of another embodiment of an energy storage device according to the invention;

8th a schematic representation of another embodiment of an energy storage device according to the invention;

9 a further schematic representation of the embodiment of 8th ;

10 a schematic representation of another embodiment of an energy storage device according to the invention;

11 a schematic representation of another embodiment of an energy storage device according to the invention; and

12 a schematic representation of an embodiment of the energy storage device with a housing.

In 1 an embodiment of an electrochemical energy storage device according to the invention is shown. Such an energy storage device can be used, for example, as a battery for, in particular, portable computers, mobile telephones and other consumer applications. Other application areas include, for example, power tools, garden tools and electrically powered vehicles, such as hybrid or plug-in hybrid vehicles or fully electrically powered vehicles.

Such an electrochemical energy store may in particular be a lithium-ion battery. He can do a cell space 1 in which at least one anode, at least one cathode and an arranged between the anode and cathode electrolyte is arranged. Furthermore, can be arranged between the anode and cathode, a separator. The cell space 1 according to 1 For example, it can be configured as a cell coil in a manner known per se and be open approximately at its lateral areas. Furthermore, the cell space 1 be surrounded by a housing at least partially or may optionally in an area outside the cell space 1 run this surrounding housing.

In the context of the present invention, an anode of a lithium-sulfur battery may, in particular, be an electrode which is made entirely of lithium or at least partially comprises lithium. Furthermore, an anode in the context of the present invention may be understood to mean an electrode which, in particular, can reversibly intercalate lithium ions. For example, a cathode may include sulfur or sulfur-containing composites as the active material, a conduction improver such as carbon black, and a binder when the energy storage is about a lithium-sulfur battery. As separators known from the conventional lithium-ion technology separators, such as Celgard can be used and as the electrolyte may further conductive salts such as LiPF ₆ or Li-bis (trifluoromethyl) sulfonimide in ethers, such as 1,2-dimethoxyethane or 1, 3-dioxolane, or find in carbonated solvents use.

It is furthermore at least one current conductor connected to the at least one anode 2 and at least one current collector connected to the at least one cathode 3 provided for tapping electrical energy. The current collector 2 . 3 For example, metallic sheets such as copper may be used. It is at least one current conductor 2 . 3 , preferably at several or at all Stromableitern 2 . 3 , a fluidizable material 5 arranged between and the interior of the cell space 1 a fluidic connection is provided. Preferably, this may be the fluidizable material 5 especially completely outside the cell space 1 be arranged. In this case, the fluidizable material 5 fluidize at a temperature that is at a defined limit, wherein the limit at a defined distance above an operating temperature of the at least one Stromableiters 2 . 3 lies. For example, the fluidizable material 5 Fluidize at a temperature or form a fluid that is in a range of greater than or equal to 100 ° C to less than or equal to 200 ° C, in particular in a range of greater than or equal to 100 ° C to less than or equal to 160 ° C.

In the embodiment according to 1 forms the fluidizable material 5 one on the current collector 2 . 3 arranged container 4 , In detail are according to 1 four containers 4 provided, which refers to the two current conductors 2 . 3 to distribute. In the containers 4 is a chemically inert fluid 6 arranged, which in fluidizing the fluidizable material 5 in the cell space 1 can reach and so can perform a thermal stabilization.

For example, this can be done in the container 4 or in the containers 4 arranged fluid 6 an ionic liquid, an oil or a powder or include. It can do this in the container 4 or in the containers 4 arranged fluid 6 at room temperature or at an operating temperature, in particular of the current conductor 2 . 3 be firm and form a fluid only at a defined limit, or even at room temperature or at an operating temperature in particular of the current conductor 2 . 3 form a fluid. Alternatively or additionally, in the container 4 or in the containers 4 at least one fluid polymerizable monomer can be arranged.

In addition, in order not only to reduce thermal runaway but also to reduce its consequences or prevent it altogether, for example in the container 4 or in the containers 4 , at least one flame-retardant substance be provided.

Furthermore, in 1 Guiding devices shown which, for example, in the containers 4 arranged fluid in the interior of the cell space 1 lead or lead. According to 1 are four guardrails 11 provided, which by a suitable orientation, the fluid in the interior of the cell space 1 For example, by guiding to a corresponding opening, can lead. In detail, the fluid will flow down through gravity and through the baffles into the cell space 1 directed. It will be apparent to those skilled in the art that for the exemplary case, for example, when the energy store is rotated 90 degrees, and a current collector 2 . 3 above the cell space 1 located, as in other cases on Leiteinrichtungen 11 may be waived if necessary.

In 2 is a side view of the current collector 2 . 3 shown on a container 4 is arranged. In 2 it can be seen that the container 4 by a between the container 4 and the current collector 2 . 3 arranged liability mediator 7 may have improved adhesion. Additionally or alternatively, an adhesive element or fastening means may be provided, which is about a mechanical connection between the container 4 and the current collector 2 . 3 can produce or improve.

An example of this embodiment is in 3 shown. In 3 it can be seen that the container 4 for example, by two in particular U-shaped brackets 8th at the current conductor 2 . 3 can be attached. The brackets 8th For example, from one side to the current collector 2 . 3 be pushed so that they are the current conductor 2 . 3 together with a part of the container 4 embrace and the container 4 so at the current conductor 2 . 3 fasten or clamp.

Another example of a mechanical connection between the container 4 and the current collector 2 . 3 or for a connection between the container 4 and the current collector 2 . 3 by a mechanical connecting means is in 4 shown. According to 4 can the container 4 by the introduction of a connecting means, such as a connecting pin 12 , from above through one or a plurality of edge regions of the container 4 in or on the current conductor 2 . 3 be attached. In detail, the connecting means above the container and / or below the Stromableiters 2 . 3 be bent or other, known in the art, a mechanical connection between the container 4 and the current collector 2 . 3 provide. For example, the connecting means or the connecting pin can be designed screw or nail-like.

Another example of a mechanical connection between the container 4 and the current collector 2 . 3 or for a connection between the container 4 and the current collector 2 . 3 by a mechanical connecting means is in 5a and 5b shown, where 5a and 5b each offset by 90 ° side views on a current conductor 2 . 3 show an energy storage device according to the invention. According to the 5a and 5b is the container 4 on a plug-on body 13 attached to the current collector 2 . 3 is deferrable and the latter embraces. In this case, the slip body 13 the current conductor 2 . 3 fully embrace this as in 5b is shown, or designed for example U-shaped and partially embrace the current conductor.

In particular, for the latter embodiment, it may be advantageous if a plug-on body 14 by providing mechanical connection means such as connection pins 15 as described above, as described with reference to FIG 4 described and in 6 is shown.

In 7 a further embodiment is shown. According to 7 is the fluidisable material 5 as a coating 9 of the current conductor 2 . 3 educated. In this case, the coating 9 For example, include only the fluidizable material and be applied as by lamination.

A corresponding embodiment according to 7 with a guide is in the 10 shown. In 10 It can be seen that localized and separate coatings 9 of the fluidizable material 5 are provided. Below the individual coatings 9 again is a baffle 11 as a guide on the current conductors 2 . 3 shown.

In a further embodiment, in the 8th and 9 is shown, wherein the 9 a side view of the current conductor 2 . 3 shows is the fluidizable material 5 embedded in a binder material 10 or lies in a matrix of a binder material 10 in front.

A corresponding embodiment according to 8th . 9 with a guide is in the 11 shown. In 11 can be seen, the localized and separate areas of binder material 10 with embedded fluidizable material 5 are provided. Below the individual areas is in turn each a baffle 11 as a guide on the current conductors 2 . 3 shown.

The 12 shows a further embodiment of the energy storage device according to the invention. In this embodiment, the current conductors 2 . 3 lengthened designed so that they come out of a housing 16 can project. As a result, in particular the cell winding together with current conductors 2 . 3 or the fluidizable material 5 be protected and also a trouble tapping electrical energy to the current conductors 2 . 3 to be possible. In this case, the material of the current collector 2 . 3 outside the case, be the same or the same as the current conductor 2 . 3 inside the case.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008008483 A1 [0003]
• US 2009/0104523 A1 [0004]
• DE 102009051216 A1 [0005]

Claims (13)

Electrochemical energy store, in particular lithium-ion battery, comprising a cell space ( 1 in which at least one anode, at least one cathode and an electrolyte arranged between the anode and the cathode is arranged, at least one current conductor connected to the at least one anode ( 2 ) and at least one connected to the at least one cathode current conductor ( 3 ) is provided for tapping electrical energy, and wherein at least one current conductor ( 2 . 3 ) a fluidizable material ( 5 ), wherein between the fluidizable material ( 5 ) and the interior of the cell space ( 1 ) a fluidic connection is provided, and wherein the fluidisable material ( 5 ) is fluidized at a temperature which is at a defined limit value, the limit value being at a defined distance above an operating temperature of at least one of the current conductors ( 2 . 3 ) lies. Energy store according to claim 1, wherein the fluidisable material ( 5 ) is fluidized at a temperature ranging from greater than or equal to 100 ° C to less than or equal to 200 ° C. Energy store according to one of claims 1 or 2, wherein the fluidisable material ( 5 ) outside the cell space ( 1 ) is arranged. Energy store according to one of claims 1 to 3, wherein the fluidisable material ( 5 ) comprises an ionic liquid or a polymer. Energy store according to one of claims 1 to 4, wherein the fluidisable material ( 5 ) embedded in a binder material ( 10 ) is present. Energy store according to one of claims 1 to 5, wherein the fluidisable material ( 5 ) as a coating ( 9 ) of the current conductor ( 2 . 3 ) is trained. Energy store according to one of claims 1 to 4, wherein the fluidisable material ( 5 ) on the current conductor ( 2 . 3 ) arranged container ( 4 ), in which a chemically inert fluid ( 6 ) is arranged. Energy storage according to claim 7, wherein the container ( 4 ) by a bonding agent ( 7 ) or by a mechanical fastener on the current conductor ( 2 . 3 ) is attached. Energy store according to claim 7 or 8, wherein in the container ( 4 ) arranged fluid ( 6 ) comprises an ionic liquid, an oil or a powder. Energy store according to one of claims 7 to 9, wherein in the container ( 4 ) at least one fluid polymerizable monomer is arranged. Energy store according to one of claims 1 to 10, wherein on at least one current conductor ( 2 . 3 ) at least one guide device for guiding a fluid into the interior of the cell space ( 1 ) is provided. Energy store according to claim 11, wherein the at least one guide device as a guide rail ( 11 ) is configured. Energy store according to one of claims 1 to 12, wherein the fluidisable material ( 5 ) is present together with at least one flame retardant substance.

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