Recording and reversible fixation of battery cells

Abstract

A device for receiving and reversibly securing individual battery cells in a high-voltage storage device is provided. It comprises at least one first connecting element and at least one second connecting element, wherein the first and second connecting elements are complementary to one another, and the combination of the two connecting elements forms a detachable force-locking and form-locking connection.

Description

The present disclosure relates to a device for receiving and reversibly fixing individual battery cells in a high-voltage accumulator, to a method for producing a high-voltage accumulator for a vehicle, to a high-voltage accumulator which contains the device, and to a vehicle having the high-voltage accumulator.In the current prior art, plastic is cast around battery cells in a high-voltage accumulator for motor vehicles in order to achieve a secure fixing of the battery cells. In order to fix battery cells in high-voltage storage devices for motor vehicles, these are partially encapsulated by plastic material, or the high-voltage storage device is foamed with plastic material, in order to thus achieve reliable fixing of the battery cells in the high-voltage storage device.When the individual battery cells are encapsulated with plastic, a form-fit connection is produced. The replacement of individual battery cells is then no longer possible. In the event of a defect in individual battery cells, a power loss of the high-voltage accumulator must therefore be accepted, or the entire high-voltage accumulator must be replaced, since it is not possible to replace only individual defective battery cells. In the case of a used vehicle, replacement can be so costly that replacement does not renounce and thus economic total damage arises to the customer or vehicle user. A further challenge is the difficult, if not impossible, recycling of the high-voltage accumulator on account of the cured plastic during foaming / casting. In addition, the individual battery cells and the raw materials installed therein can no longer be recycled. This hinders the circular use of valuable raw materials.Against this background, it is an object of the invention to provide a device which enables replacement of the battery cells if the high-voltage accumulator is not foamed. Individual battery cells can thus be exchanged, and the re-useability of the high-voltage accumulator with exchanged battery cells can be ensured. This results in a high-voltage accumulator which can be removed from battery cell bees with little effort. This type of high-voltage accumulator offers the advantage that it can be serviced at the cell level. Defective battery cells can thereby be corrected or aged battery cells can be replaced and used further for other applications, for example stationary storage devices such as "home storage".The object is achieved by the features of the independent patent claims. Advantageous further developments of the invention are the subject matter of the dependent patent claims and of the description and drawings.The object is then achieved by a device for receiving and reversibly fixing individual battery cells in a high-voltage accumulator. The device can comprise at least one first connecting element and at least one second connecting element. The two connecting elements can be formed complementary to each other and the connection of the two connecting elements can form a releasable force-fit and form-fit connection.In the sense of the present disclosure, battery cell is a specific type of battery cell, preferably a cylindrical battery cell. This has a cylindrical design. These battery cells may be formed of a metal case, which may be made of, for example, aluminum or steel and includes a cathode, anode, and electrolyte. The anode and cathode are mounted within the battery cell in a spiral form or a flat, rolled-up "lamella" while the electrolyte lies between them. They are frequently used in portable devices such as laptops, mobile phones, power tools, flashlights and e-bikes. They are also used in larger energy storage systems, such as electric vehicles and stationary energy stores. The most common sizes of cylindrical battery cells are 18650 (18 mm in diameter and 65 mm in length) and 21700 (21 mm in diameter and 70 mm in length). However, there are also a large number of other sizes, for example 4680 (46 mm in diameter and 80 mm in length) or 4695 (46 mm in diameter and 95 mm in length), depending on the application requirements and manufacturer.In the sense of the present disclosure, reversible fixing is a method for temporarily connecting objects, which makes it possible to easily release the connection again without permanent damage to the objects. The fixation can be achieved by various methods such as Velcro fasteners, pushbuttons, screw connections or by special adhesives. This type of fixation has the advantage of enabling quick and repeated connections of objects.For the purposes of the present disclosure, a releasable force- and form-fit connection can be a push-button connection. A push-button connection consists of two elements, a so-called "nub" and a "bowl". The first connection element may be the knob and may be described as a type of button or pin having a round base and a protruding shoulder. The base of the stud is usually fastened to a surface to be connected, while the protruding shoulder points upward or outward, i.e. away from the surface. The second connecting element may be the bowl and may be described as a kind of lid with a recess in the middle. In this case, the second connecting element can be attached to the respective end of the battery cell and can circumferentially engage around the battery cell and thereby hold it.For the purposes of the present disclosure, the cutout of the second connecting element can be shaped such that it fits on the protruding shoulder of the knob. When the two elements are placed on top of each other, the first connecting element fits into the recess of the bowl and fixes it in place. The first connecting element and the second connecting element of the push button have a resilient action allowing them to snap-lock together. To release the connection, the first connecting element can be pressed to remove the second connecting element from it.The advantage of the releasable force-fit and form-fit connection, preferably the pushbutton connection, is to promote a fast and simple assembly and disassembly processes and at the same time to ensure a secure mechanical connection. This enables a quick and secure accommodation of battery cells in a high-voltage accumulator, wherein the releasable force-fit and form-fit connection is a reversible fixing. Foaming of the high-voltage accumulator can be dispensed with here, and the replacement of defective battery cells and the re-useability of aged battery cells and of the high-voltage accumulator with new battery cells is made possible.Possible refinements of the above-described device are explained in detail below.It can be provided that the at least first connecting element is arranged on a strip in a form-fitting manner.For the purposes of the disclosure, "positive locking" and "non-positive locking" can be understood as terms from the field of mechanical engineering in order to describe the manner in which two mechanical parts are connected to one another. Positive connections result from the geometric shape of the parts, i.e. they are shaped so that they fit perfectly into each other. An example of a positive connection is a pin that fits into a hole. When the pin is pushed into the hole, the geometric features of the pin prevent it from moving. Force-fit connections, on the other hand, result from forces exerted on the parts. The parts are not necessarily geometrically matched but pressure, tension or friction create a connection between them. An example of a force-fit connection is a screw which is guided through a nut. By turning the screw into the nut, a force-fit connection is created between the two parts.In the sense of the present disclosure, a strip can be a fastening and / or power distribution strip. This can be arranged at the upper and lower end of the battery cell, preferably the cylindrical battery cell. Negative and positive polarities can be connected to the power distribution strip. For this purpose, the power distribution strip can form conductor tracks. The power distribution strip can preferably be the cell contacting system of a high-voltage accumulator. Furthermore, the form-fit arrangement of the first connecting element can be effected mechanically, so that an arrangement is produced which resembles a snap-fastener band made of metal and / or plastic. It can also be that the battery cells are combined in groups to form so-called modules, each module being connected to its own strip. Thus, replacement and repair can be carried out without problems at the module level, i.e. not the entire high-voltage accumulator but only one module has to be replaced. This facilitates the re-useability and the battery cells can also be recycled and used further after their original use in a high-voltage accumulator. By omitting a cohesive fixing, as is produced when using plastic due to the encapsulation or foaming, secure fixing can nevertheless be made possible. Exchanged, aged battery cells can be used further, for example, in a stationary memory, for example for use in private households as "home storage".It can be provided that the first connecting element and / or the second connecting element is electrically conductive. Thus, individual battery cells may be electrically connected and still remain replaceable. This makes it possible to avoid a complete high-voltage accumulator having to be replaced on the basis of individual battery cells and even having to be disposed of. Depending on the state of the individual battery cells, these can be used further in stationary storage devices.It can be provided that the first connecting element and the strip are formed from a plastic and the strip is coated with an electrically conductive material.For the purposes of the present disclosure, the synthetic strip can be produced from various materials, for example from polypropylene (PP) or polyethylene (PE). It is important that the material have high strength and resistance to chemicals and UV light in order to securely hold and protect the battery cells together. This enables the individual cells to be removed safely and further operated in a stationary storage.It can be provided that the second connecting element is designed to receive and hold in a force-fit manner at least one battery cell. As a result, it is possible to dispense with the plastic foam which is harmful to the environment and which prevents recycling of the high-voltage accumulator and replacement of individual battery cells during the encapsulation, since the second connecting element detachably connects the battery cell to the first connecting element and thus enables a secure and stable arrangement and connection to the strip.It can be provided that the second connecting element forms a battery contact surface on an inner side.For purposes of the present disclosure, a battery contact surface may be a particular surface used in connection elements such as pushbuttons to firmly and securely hold the battery cell. It is designed to form a force fit connection with the battery and often has a profile such as a saw tooth profile to produce a higher clamping effect. This prevents the battery cell from unintentionally becoming detached from the connection and at the same time ensures a stable connection.It can be provided that the second connecting element is designed to receive a plurality of battery cells in a modular manner and to hold them in a force-fitting manner.In the sense of the present disclosure, modular can mean that the second connecting element forms a module when it simultaneously holds more than one battery cell in a force-fit manner. A modular battery arrangement makes it possible to better use the battery cells and to optimize the energy consumption. Resource efficiency increases through the use of a modular system because the battery cells are better reused and recycled. This may result in more efficient use of resources and reduce the need for new battery cells. A modular battery system provides the ability to more efficiently handle and mount the battery cells during the production process. This can lead to a reduction of wastes and energy consumption, which contributes to more durable production. A force-fit connection of the battery cells in a modular system reduces the risk of loosening or damage. This can minimize the risk of malfunctions and potential safety issues.It can be provided that a high-voltage accumulator for a vehicle contains the device within the meaning of the disclosure. A vehicle may be provided that contains a high-voltage accumulator within the meaning of the disclosure, wherein the high-voltage accumulator contains the device for receiving and reversibly fixing individual battery cells within the meaning of the disclosure.Such a high-voltage accumulator and vehicle with this high-voltage accumulator lead to more efficient use of resources because the need for new battery cells is reduced by only individual defective batteries being able to be replaced by the reversible fixing instead of having to avoid an entire high-voltage accumulator which is not recyclable when foaming due to the cured plastic.It can be provided that a method for producing a device for receiving and reversibly fixing individual battery cells is provided. Here, a first connecting element and a second connecting element are formed to be complementary to one another, and the connection of the two connecting elements forms a releasable force-fit and form-fit connection.By a force-fit and form-fit connection of the battery cells by means of the first and second connecting elements, the risk of loosening or damage is reduced. This can minimize the risk of malfunctions and potential safety issues. In addition, fast and simple assembly and disassembly processes are thus facilitated and a secure mechanical connection of the battery cells is ensured. This enables a quick and secure accommodation of battery cells in a high-voltage accumulator, wherein the releasable force-fit and form-fit connection represents a reversible fixing. Foaming of the high-voltage accumulator with plastic can be dispensed with here, and the replacement of individual defective battery cells and the re-useability of aged battery cells and of the high-voltage accumulator with new battery cells is made possible. Thus, the battery cells can be better utilized by being reused and recycled, which increases the resource efficiency. This may result in more efficient use of resources and reduce the need for new battery cells.The above description can be summarized in other words and on a possible more specific configuration of the disclosure as described below, wherein the following description is to be interpreted as not restrictive for the disclosure.The battery cells in the high-voltage storage devices for motor vehicles are encapsulated with plastic by casting, in order to achieve secure fixing of the battery cells in this way. In order to fix battery cells, in particular round cells, in high-voltage accumulators for motor vehicles, these are partially encapsulated by plastic, in order to thus achieve reliable fixing of the battery cells in the high-voltage accumulator.When the individual battery cells are encapsulated with plastic, it is not possible to exchange individual battery cells. In the event of a defect in individual battery cells, a power loss of the high-voltage accumulator must therefore be accepted, or the entire high-voltage accumulator must be replaced. In a used vehicle, this means the total economic damage. A further disadvantage is the difficult, if not impossible, recycling of the raw materials installed in the high-voltage accumulator or the battery cells. This hinders the circular use of valuable raw materials.The present disclosure is based on achieving the fixing of the individual battery cells not in a form-fitting manner with plastic, but in a combination of force-fitting and form-fitting manner by a mechanical path.The present disclosure is to attach a push-button connection to commercially available round cell battery cells. The key bowl of the push button, the second connection element, may enclose the battery cell. The knob of the pushbutton, the first connecting element, is fastened in a form-fitting manner to a strip, preferably to the current-carrying conductor track. The push button comprising the first and second connecting elements and the strip can also be made of plastic. For power guidance, the power distributor and the pushbutton can be coated. A snap fastener strip made of metal or plastic could be provided, on which the knobs are applied mechanically, positively.The above with respect to the device also applies analogously to the method for producing and the high-voltage spoke and to the vehicle and vice versa.An optional embodiment will be described below with reference to FIGS. 1 and 2. FIG. 1 schematically shows a cross section of a device according to the disclosure FIG. 2 schematically shows a cross section and section of a high-voltage accumulatorFor the sake of clarity, identical features are not provided with reference symbols throughout the figures. It is obvious that these are the same structural elements.FIG. 1 shows a schematic and cross-section of a battery cell 1 It is not shown how the first connecting element 3 is arranged on a strip 4, 5, this being shown in FIG. 2. The battery cell 1 is at least partially surrounded by the second connecting element 2. The second connecting element 2 forms a battery contact surface 6. This is arranged on an inner side of the second connecting element 2. The battery cell 1 is held even more firmly and securely by the battery contact surface 6. The second connecting element 2 encloses the first connecting element 3 at least partially. In addition, the first and second connecting elements 3, 2 are formed to be complementary to one another and form a connection which forms a releasable force-fit and form-fit connection. The second connecting element 2 surrounds the battery cell 1 on the circumferential side.FIG. 2 shows a cross section and section of a high-voltage accumulator. Two strips 4 are provided, on which both at least one first connecting element 3 is arranged in a form-fitting manner. The upper strip 4 in FIG. 2 can be used as a power distribution strip. The first connecting element 3 can be fastened to this strip 4. As shown in FIG. 2, the strip 4 can also be arranged at the bottom at the end of the battery cell 1. In this case, it can assume the function of a fastening strip without current conduction. Depending on the exact structure and the internal electrical wiring of the high-voltage accumulator, the strip 4 can also each assume the function of the other strip or, in combination, both strips can also be current distribution strips. Furthermore, it is shown how the second connecting element 2 is designed to receive a plurality of battery cells 1 in a modular manner and to hold them in a force-fit manner. In FIG. 2, this is shown by way of example on the basis of two battery cells 1, which are clamped in a modular connecting element 2 with a module spacer 5 in each case between the battery cells 1 in order to ensure secure retention. It can also be seen here that nevertheless one associated first connecting element 3 is arranged on the strip 4 per battery cell 1. This can be used for stability and electrical connection.Reference numerals denote reference numerals1 Battery cell 2 Second connection element 3 First connection element 4 Strip 5 Module spacer 6 Battery contact surface

Claims

Device for receiving and reversibly fixing individual battery cells (1) in a high-voltage accumulator, comprising: - at least one first connecting element (3); and - at least one second connecting element (2); wherein the first and second connecting elements (3, 2) are formed complementary to one another and the connection of the two connecting elements (3, 2) forms a releasable force-fit and form-fit connection.Device according to claim 1, wherein the at least first connecting element (3) is arranged in a form-fitting manner on a strip (4).Device according to one of the preceding patent claims, wherein the first connecting element (3) and / or second connecting element (2) is electrically conductive.Device according to one of the preceding patent claims, wherein the first connecting element (3) and the strip (4) are formed from a plastic; and the strip (4) is coated with an electrically conductive material.Device according to one of the preceding patent claims, wherein the second connecting element (2) is designed to receive and hold in a force-fit manner at least one battery cell (1).Device according to one of the preceding patent claims, wherein the second connecting element (2) forms a battery contact surface on an inner side.Device according to one of the preceding patent claims, wherein the second connecting element (2) is designed to receive a plurality of battery cells (1) in a modular manner and to hold them in a force-fitting manner.High-voltage accumulator for a vehicle, which contains the device according to Patent Claim 1.Vehicle with high-voltage accumulator according to Patent Claim 8.Method for producing a device for receiving and reversibly fixing individual battery cells (1), in which a first connecting element (3) and a second connecting element (2) are formed to be complementary to one another and the connection of the two connecting elements (3, 2) forms a releasable force-fit and form-fit connection.

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