Structural battery enclosure

Abstract

The invention relates to a structural battery housing. A battery having multiple layers, comprising: a first conductive layer; a second layer substantially made of carbon fiber reinforced plastic; a third layer made of glass fiber reinforced plastic; a fourth layer made of carbon fiber reinforced plastic and LiFePO4, wherein the weight ratio of LiFePO4 to carbon fiber is 2:1 to 2.5:1; and a fifth conductive layer, characterized in that the battery is substantially surrounded by a layer made of glass fiber filled polyester.

Description

Technical Field

[0001] The present invention relates to a structural battery, in particular a structural battery for vehicle manufacturing, in particular a structural battery for aircraft manufacturing or aviation, or a structural battery used in a vehicle, in particular in an aircraft or spacecraft. In addition, the present invention also relates to a method for manufacturing a structural battery. Background Art

[0002] In many vehicles, in particular in spacecraft or aircraft, high requirements are placed on the energy storage density of the energy storage, that is, as much electrical energy as possible should be stored per unit of weight of the energy storage. Energy storage can be understood, for example, as a battery, and preferably as a rechargeable battery, such as is used in electric vehicles or hybrid vehicles. The energy storage density (or energy density, in English "energy density") is measured, for example, in Watt hours per kilogram (Wh / kg).

[0003] A battery comprises an anode, a cathode and an electrolyte, in which both electrodes are immersed. Together they form a battery cell. There are also batteries consisting of multiple battery cells connected to each other. The anode and cathode are often separated from each other by a barrier, the so-called separator. The battery can contain solid, liquid or polymer electrolytes. In addition, the battery can be designed as a rechargeable battery. What most batteries have in common is that they have a relatively low specific charge capacity, that is, in order to transport a larger amount of current, a heavier battery is required. Therefore, there is no shortage of attempts to design batteries to be as light and miniaturized as possible, for example by using lightweight polymer-based electrodes. Another idea is to develop batteries with additional functions, so-called multifunctional batteries. Such additional functions are, for example, that the battery also has a supporting function. Such batteries with additional load-bearing properties are also called structural batteries. In some cases, such batteries are also called stacked energy storage systems.

[0004] Document US Pat. No. 9,276,240 B2 describes a flat stacked cell arrangement whose side surfaces are smaller than their front surface.

[0005] Starting from the known prior art, the object of the present invention is to provide an improved stacked energy storage system, in particular an energy storage system with a higher energy density. Summary of the invention

[0006] Now, surprisingly for a person skilled in the art, it has been proposed that a battery having a plurality of layers compensates for the disadvantages of the prior art, the layers comprising: a first electrically conductive layer; a second layer substantially made of carbon fiber reinforced plastic; a third layer made of glass fiber reinforced plastic; a third layer made of carbon fiber reinforced plastic and LiFePO 4The fourth layer is made of LiFePO 4 The cell has a weight ratio of 2:1 to 2.5:1 to carbon fiber; and a conductive fifth layer, characterized in that the cell is essentially surrounded by a layer made of glass-fiber-filled polyester. Such cells have load-bearing properties and are also referred to as structural cells. PET, PBT or PEI can preferably be used as glass-fiber-filled polyester. In addition, 15% CF 3 SO 3 Li(LiTriflat). Preferably, the conductive material of the first and / or fifth layer is selected from metal or graphite. Preferably, the encapsulation layer made of glass-fiber-filled polyester is substantially coated with metal and / or ceramic on the side facing away from the battery. This ceramic layer is waterproof and is particularly suitable for thermoplastics filled with clay minerals, preferably polypropylene. This material is also called clay-polymer composites or clay-PP composites. Preferably, the encapsulation layer made of glass-fiber-filled polyester contains glass fiber fabric. Preferably, the encapsulation layer made of glass-fiber-filled polyester is substantially coated with SiO on the side facing away from the structural battery. 2 .SiO 2 The coating can be carried out by plasma spraying, CVD or PVD. Preferably, the edges of the first to fifth layers are arranged in a stepped manner. As a result, individual structural cells can be connected to each other. At the same time, short-side designs in the form of tongues and grooves can also be used. The invention also includes a method for manufacturing a battery according to one of the above claims, characterized in that the first and fifth layers and the encapsulating layer are positioned by AFP or ATL and reinforced by laser or ultrasonic welding, as well as a plane provided with a plurality of structural cells according to the invention, at which the individual cells are connected to each other at their edges. Preferably, the connected structural cells are connected by means of a heated press.

[0007] The above-mentioned and other aspects, features and advantages of the present invention are described in detail below with reference to the accompanying drawings, with reference to examples of implementation forms. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A common battery structure is shown. Figure 2 A structural battery and its housing according to the present invention are shown. Figure 3 It is shown how a battery structure can be coated with an encapsulation layer according to the invention using a laying device. Figure 4 It shows how multiple structural cells can be positioned on an existing surface and connected to each other.

[0009] The same reference numerals are used in the drawings for the same or at least similar elements, components or aspects.It should be noted that embodiments will be described in detail below, which are only illustrative and not restrictive. DETAILED DESCRIPTION

[0010] Figure 1 A common structural battery 1 is shown. The structural battery is characterized by its layered structure. An anode made of a carbon fiber composite material 3 is installed flat on a planar collector 2. A separator layer made of glass fiber reinforced plastic, i.e. a separator 4, is connected to the anode, and behind the separator is a cathode 5. The cathode 5 is made of carbon fiber reinforced plastic, and lithium iron phosphate is added to its surface. This is followed by another collector layer 6. An interface 7 is fixed to the cathode collector layer 6, and an interface 8 is also installed on the anode collector layer 2. The interface allows current to be taken from the structural battery and connected to an electrical appliance.

[0011] Figure 2 A structural battery and a housing thereof according to the present invention are shown.

[0012] The upper and lower ends of the anode and cathode collectors in the form of a conductive medium are printed on the conventionally stacked anode, cathode and separator layers. The collectors are connected to an interface that allows the battery to be connected to an electrical consumer and to extract charge. The battery is wrapped by a first layer 16 made of glass fiber reinforced thermoplastic. Polyethylene terephthalate, polybutylene terephthalate or polyesterimide can be used as thermoplastics. The embedded glass fibers can be short fibers, long fibers, fabrics or fiber meshes. The first layer 16 protects the battery from mechanical influences and achieves electrical insulation from the surrounding environment. A second layer 17 is connected around the first layer, the purpose of which is to protect the battery from moisture or chemical environment. In addition, a plastic and clay mineral mixture is used. The mixture has thermoplastic properties, allowing it to be protected from such media by the clay minerals that swell when exposed to water. Another coating 18 made of silicon dioxide is coated on the surface of the second layer 17. The coating can be applied by plasma adsorption or CVD and makes the structural battery scratch-resistant and corrosion-resistant. The composite body made of layers 16 , 17 and 18 protects the battery from mechanical shocks, electrical current and thermal loads.

[0013] Figure 3 It is shown how a wrapping layer 23 according to the present invention is applied to a structural cell 21 using a laying device 22 .

[0014] The laying device 22 can be, for example, a tape laying machine or a wire laying machine. The tape laying machine allows the tape to be laid on the surface as specified. The tape can have a width of 5 to 50 cm, for example. The tape can be processed into a coil and has adhesive properties that can prevent the laid tape from sliding. The basic difference of the wire laying machine is that it lays tapes with a lower width of 5 mm to 5 cm. The wrapping layer 23 can be laid on the actual structural battery by the laying device 22. The laying device 22 has a manipulator 24, which allows the laying head to be placed in the desired direction and position and moved in the desired direction. In addition, the laying device 22 also includes a roller with a thermoplastic protective film 25. Using the thermoplastic protective film 25, the conductor circuit printed on the protective film can also be applied to the structural battery 21, and the conductor circuit constitutes the cathode or anode collector 26 of the structural battery. This laying device 22 allows the wrapping layer 23 according to the present invention to be applied to the structural battery 21 at a higher speed.

[0015] Figure 4 It is shown that a plurality of structural batteries 31 are placed on an existing surface 30 and connected to one another. For this purpose, the short edges 33 of the structural batteries 31 are stepped or tongue-and-groove shaped. In this way, a plurality of battery cells 31 can be connected to one another in a form-fitting manner. The thermoplastic housing of the battery is melted by a heated press 32 arranged along the connection points 34 of the different batteries 31, so that the battery cells can be connected to one another. Thus, a plurality of connected battery cells 35 are formed, each of which is electrically insulated from one another. Thus, for example, the surface of the connection device and the structural batteries are arranged in a planar manner.

[0016] Although the present invention is shown and described in detail in the drawings and the above description, it is intended that such showing and description are only illustrative and exemplary, not restrictive, and therefore the present invention is not limited by the disclosed embodiments. In the claims, the word "having" does not exclude other elements and the indefinite article "a (ein)" does not exclude a plurality.

[0017] The mere mention of certain features in different dependent claims does not limit the subject matter of the invention. Combinations of these features can also be used to advantage. Reference signs in the claims should not limit the scope of the claims.

[0018] List of Reference Numerals

[0019] 1 Structural battery

[0020] 2 Anode collector

[0021] 3 Anode

[0022] 4 Partition

[0023] 5 Cathode

[0024] 6 Cathode collector

[0025] 7, 8 Interface

[0026] 12 Anode

[0027] 13. Partition

[0028] 14 Cathode

[0029] 15 Collector

[0030] 16 Layers made of glass-fiber reinforced thermoplastic

[0031] 17 Layer made of thermoplastic with clay minerals

[0032] 18 Silica coating

[0033] 21 Structural battery

[0034] 22 Laying equipment

[0035] 23. Shell

[0036] 24 Robot

[0037] 25 Roller with thermoplastic protective film

[0038] 26 Collector

[0039] 30 Surface

[0040] 31 Multiple structural batteries

[0041] 32 Heated press

[0042] 33 Short side of structural battery

[0043] 34 Connection points

[0044] 35 connected battery cells

Claims

1. A battery having a plurality of layers, the battery comprising, in sequence: a conductive planar first layer comprising a conductive material; a second layer made of carbon fiber-reinforced plastic; a third layer made of fiberglass-reinforced plastic; a fourth layer made of carbon fiber reinforced plastic and LiFePO4, wherein the weight ratio of LiFePO4 to carbon fiber is 2:1 to 2.5:1; a conductive fifth layer comprising a conductive material, Characterized in that the battery has a layered structure and is wrapped by a wrapping layer made of glass fiber-filled polyester, The invention is characterized in that the encapsulating layer is coated with a ceramic layer on the side facing away from the battery, and the ceramic layer is made of polypropylene filled with clay minerals, and The feature of the invention is that the wrapping layer is further coated with SiO2 on the side facing away from the battery.

2. The battery according to claim 1, characterized in that The conductive material of the first and / or fifth layer is selected from metal or graphite.

3. The battery according to claim 1 or 2, characterized in that: The wrap made of glass-filled polyester contains glass fiber fabric.

4. The battery according to claim 1 or 2, characterized in that: The edges of the first to fifth layers are arranged in a stepped manner.

5. A method for producing a battery according to any one of the preceding claims, characterized in that The first and fifth layers and the wrapping layer are positioned by AFP or ATL and reinforced by laser or ultrasonic welding.

6. A component having a plurality of batteries according to any one of claims 1 to 4 arranged in a plane, characterized in that: The individual cells are connected to one another at their edges.

7. The component according to claim 6, characterized in that The batteries according to claim 1 are connected to one another by means of a heated press.

Images