Method for manufacturing a battery storage system, battery storage system and vehicle

Abstract

The invention relates to a method for manufacturing a battery storage device, comprising a housing with a receiving chamber, at least one battery cell arranged in the receiving chamber, and a temperature control system for supplying and / or removing heat from the at least one battery cell. In the method according to the invention, in a first step, the at least one battery cell is heated by means of the temperature control system. In a second step, an expandable potting compound is poured into the receiving chamber. In a third step, the potting compound is expanded to fill the receiving chamber with the potting compound. The invention further relates to a battery storage device (12) manufactured using such a method and to a vehicle with such a battery storage device (12).

Description

[0001] The invention relates to a method for manufacturing a battery storage device, in particular a battery storage device for a vehicle, comprising a housing with a receiving space, at least one battery cell arranged in the receiving space, and a temperature control system for supplying and / or removing heat from the at least one battery cell. The invention further relates to a battery storage device manufactured using such a method and to a vehicle with such a battery storage device.

[0002] Vehicle battery storage systems contain a large number of unit cells or battery cells arranged in a housing. To ensure these are securely connected, it is common practice to fill the volume around the battery cells, for example with polyurethane (PU) foam.

[0003] From DE 10 2018 209 026 A1, a method for manufacturing a battery module with a plurality of battery cells is known, in which, in a first step, a plurality of battery cells are arranged in a housing of the battery module. In a second step, the housing of the battery module is foamed with a polymer, the foaming being started by heating or radiation after the polymer has been completely introduced into the housing of the battery module.

[0004] An alternative method for manufacturing a battery module is shown in EP 4 167 362 A1. In this method, in a first step, at least one cell holder is provided. In a second step, a battery cell is inserted into each through-hole of the cell holder. In a third step, potting compound is poured along the upper and / or lower surface of the cell holder body. In a third step, at least one cooling channel is provided above or below the body of the at least one cell holder.

[0005] To ensure the foam cures reliably and evenly, the battery storage system must first be heated to a temperature that is as homogeneous as possible. To accelerate cycle times and the curing process, this temperature should be as high as possible, but still low enough that the permitted operating temperature of the battery cell, including heat input from the typically exothermic reaction of the PU foam, is not exceeded. The battery storage system is usually heated using a convection oven, which is either permanently integrated into the assembly line or serves as a kind of intermediate storage unit.

[0006] The integrated battery cells have the highest thermal mass and require the largest possible surface area exposed to the airflow for rapid heating. Depending on the assembly, this is generally not guaranteed, resulting in a very long warm-up phase. The airflow increases the risk of an electrical short circuit due to the greater likelihood of airborne particles. Due to the heterogeneous airflow patterns in the convection oven, achieving a uniform temperature distribution after heating is difficult. Depending on the foam system, this can lead to varying structural properties after curing.

[0007] The present invention is based on the objective of creating a method, a battery storage system and a vehicle that feature improved structural-mechanical bonding of a potting compound to the components of the battery storage system and a reduced production time.

[0008] To solve the problem, we propose a method with the features of claim 1, a battery storage device with the features of claim 7 and a vehicle with the features of claim 8.

[0009] Advantageous variations of the process are the subject of the dependent claims.

[0010] According to a first aspect of the invention, a method for manufacturing a battery storage device is proposed, comprising a housing with a receiving chamber, at least one battery cell arranged in the receiving chamber, and a temperature control system for supplying and / or removing heat from the at least one battery cell. In the method according to the invention, in a first step, the at least one battery cell is heated by means of the temperature control system. In a second step, an expandable potting compound is poured into the receiving chamber. In a third step, the potting compound is expanded to fill the receiving chamber with the potting compound.

[0011] The process is characterized by the use of the integrated temperature control system to preheat the battery storage unit before the infusion of the expandable potting compound. This system is typically designed for ideal thermal bonding to the battery cells. Consequently, it ensures that the battery cell is brought to a uniform and controlled temperature level, resulting in a homogeneous temperature distribution within the housing during expansion. This leads to a defined and uniform structural bond between the potting compound and the battery storage unit components, particularly the battery cell and the housing. Since temperature is a critical factor in the speed of the expansion reaction, which in this case is exothermic, the preheating phase is reduced by a factor of two to four. This short preheating phase can eliminate the need for an intermediate storage tank.The process allows for a shorter production time.

[0012] The battery storage system can contain a large number of battery cells arranged within the storage compartment. A homogeneous temperature distribution for all battery cells is ensured by the temperature control system. The battery cells are advantageously designed as cylindrical cells.

[0013] The housing can have an upper and a lower part. Advantageously, the expandable potting compound is poured into the upper part and then sealed with a foam tool. In this case, the battery is manufactured upside down. Therefore, the upper part of the housing is at the bottom during the relevant manufacturing steps.

[0014] Due to the heat generated by the heating process, the potting compound begins to expand, filling any gap between the housing top and the battery cell(s). After the expanded potting compound has hardened, the battery cell(s) and all other components are bonded to each other and to the housing, particularly the housing top. Alternatively, the expansion can be regulated by the application of heat and / or radiation.

[0015] The temperature control system can be used during operation of the battery storage system to dissipate heat from the battery cell(s) and thus cool the battery storage system. The temperature control system can also be referred to as a cooling system or cooler.

[0016] In an advantageous embodiment, the temperature control system comprises at least one conduit through which a fluid flows to heat the at least one battery cell. By allowing a hot fluid to flow through the temperature control system, the battery cell is brought to a uniform and controlled temperature level, resulting in improved structural bonding of the potting compound to the components, particularly the housing and the battery cell, of the battery storage system. The conduit can be routed past the battery cell or cells. Advantageously, the conduit is routed in a meandering pattern past the battery cells.

[0017] In an advantageous embodiment, the temperature of the fluid is higher than a necessary target temperature of the battery cell for the expansion of the potting compound and lower than a maximum operating temperature of the battery cell.

[0018] In an advantageous embodiment, the fluid is a water-glycol mixture, which is also used to fill the temperature control system in later process steps.

[0019] In an advantageous embodiment, the temperature of at least one battery cell, the housing, and / or the temperature control system is recorded during expansion using a thermal imaging camera. This makes it possible to perform quality control during the manufacturing process and to ensure that the heat conduction paths, particularly between the temperature control system and the battery cell, meet the requirements. The thermal imaging camera can be designed as an infrared camera.

[0020] In an advantageous embodiment, the potting compound is a foamable and curable plastic. The foamable and curable plastic can be a thermoplastic or a thermoset. A polyurethane (PU) foam is also advantageously used.

[0021] According to a further aspect of the invention, a battery storage device is proposed which has a housing with a receiving space, at least one battery cell arranged in the receiving space, and a temperature control system for supplying and / or removing heat from the at least one battery cell, wherein a free space located between the housing and the at least one battery cell is filled with an expandable potting compound, and wherein the battery storage device is manufactured using a method according to the invention.

[0022] According to another aspect of the invention, a vehicle with at least one battery storage system according to the invention is proposed.

[0023] The following section explains in more detail a vehicle, a battery storage system, a method for manufacturing the battery storage system, and other features and advantages using an exemplary embodiment, which is schematically depicted in the figures. These figures show: Fig. 1 a vehicle with a battery storage system; Fig. 2 a perspective view of a housing base, a temperature control system and battery cells of the battery storage system; and Fig. 3 A schematic representation of a method for manufacturing the battery storage device.

[0024] In Fig. Figure 1 shows a vehicle 10 which has a drive machine designed as an electric motor, not shown.

[0025] To supply the electric motor with electricity, the vehicle 10 has a schematically represented battery storage system 12.

[0026] As in Fig. As shown in Figure 2, the electrical battery storage system 12 has a housing 14, a cell contacting system (not shown) and an energy cluster 15.

[0027] The housing 14 has a housing upper part (not shown) and a housing lower part 20, which together form a receiving space 22 in which the cell contacting system and the energy cluster 15 are arranged.

[0028] The energy cluster 15 has a large number of battery cells 16 and a temperature control system 18.

[0029] The battery cells 16 are designed as cylindrical cells 24, in particular as lithium cylindrical cells.

[0030] The temperature control system 18 serves to supply and / or remove heat from the battery cells 16. For this purpose, the temperature control system 18 has at least one line 26 which is routed past the battery cells 16 and through which a fluid serving as a coolant, for example water or a water-glycol mixture, flows.

[0031] As in Fig. As can be seen in Figure 2, the temperature control system 18 has a supply and return valve 28 for supplying the fluid to the line 26 and for removing the fluid from the line 26.

[0032] The battery cells 16 are connected to the housing 14 by means of an expandable potting compound (not shown), which is a foamable and curable plastic, in particular a foamable and curable polyurethane (PU) foam, by the potting compound filling a free space 30 between the battery cells 16 and the housing 14.

[0033] The battery storage unit 12 is manufactured using the method described below, which is in Fig. 3 is shown schematically.

[0034] In a first step S1, the battery cells 16 are heated by means of the temperature control system 18 by passing the fluid serving as a coolant through line 26 at the highest possible supply temperature. The supply temperature is higher than a target temperature of the battery cells 16 for the expansion of the potting compound and lower than a maximum operating temperature of the battery cells 16.

[0035] In a second step S2, the expandable potting compound, in particular the foamable and curable PU foam, is poured into the receiving chamber 22. The receiving chamber 22 is closed with a foam tool during expansion and curing.

[0036] In a third step S3, the expansion of the potting compound, in particular the foaming of the foam, is controlled by supplying, distributing and removing heat.

[0037] During the execution of the first step S1, the heating of the line 26, the battery cells 16, and the housing 14, particularly the battery cells 16, can be measured and monitored inline using a thermal imaging camera (not shown), for example, an infrared camera. This allows the required thermal connection of the battery cells 16 to the line 26 to be verified during the manufacturing process.

[0038] The process and the battery storage system 12 are characterized by the use of the integrated temperature control system 18 to preheat the battery storage system 12 before the expandable potting compound is poured into the receiving chamber 22. This brings the battery cells 16 to a uniform and controlled temperature level, ensuring a homogeneous temperature distribution within the housing 14 during the expansion of the potting compound. Thus, the process and the battery storage system 12 exhibit improved structural-mechanical bonding of the potting compound to the components of the battery storage system 12, particularly the battery cells 16 and the housing 14. Since the temperature is a critical factor in the speed of the expansion reaction, which in this case is an exothermic reaction, the preheating phase is reduced by a factor of two to four. Furthermore, preheating the battery storage system 12 within a single cycle time eliminates the need for an intermediate storage area for preheating.As a result, the process and the battery storage system 12 have a shortened production time. The process ensures the required thermal connection of the battery cells to the cooling circuit during the manufacturing process. Reference symbol list 10 vehicles 12 battery storage units 14 cases 15 energy clusters 16 battery cells 18 Temperature control system 20 Housing base 22 Recording room 24 round cells 26 Management 28 Flow and return valve 30 free space S1 first step S2 second step S3 third step QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2018 209 026 A1

[0003] EP 4 167 362 A1

[0004]

Claims

[1] Method for manufacturing a battery storage device (12) comprising a housing (14) with a receiving space (22), at least one battery cell (16) arranged in the receiving space (22), and a temperature control system (18) for supplying and / or removing heat from the at least one battery cell (16), comprising the following steps: a. Heating at least one battery cell (16) by means of the temperature control system (18); b. Pouring an expandable potting compound into the receiving chamber (22); and c. Expansion of the potting compound to fill the receiving space (22) with the potting compound. [2] Method according to claim 1, characterized by , that the temperature control system (18) has at least one line (26) through which a fluid flows to heat the at least one battery cell (16). [3] Method according to claim 2, characterized by, that the temperature of the fluid is greater than a necessary setpoint temperature of the battery cell (16) for the expansion of the potting compound and lower than a maximum operating temperature of the battery cell (16). [4] Method according to claim 2 or 3, characterized by , that the fluid is a water-glycol mixture, which is also used to fill the temperature control system (18) in later process steps. [5] Method according to any one of the preceding claims, characterized by , that during the expansion a temperature of at least one battery cell (16), the housing (14) and / or the temperature control system (18) is recorded by means of a thermal imaging camera. [6] Method according to any one of the preceding claims, characterized by that the potting compound is a foamable and curable plastic. [7] Battery storage device (12) comprising a housing (14) with a receiving space (22), at least one battery cell (16) arranged in the receiving space (22), and a temperature control system (18) for supplying and / or removing heat from the at least one battery cell (16), wherein a free space between the housing (14) and the at least one battery cell (16) is filled with an expandable potting compound, wherein the battery storage device is manufactured by a method according to any one of claims 1 to 6. [8] Vehicle (10) comprising at least one battery storage device (12) according to claim 7.

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