Cell module with multi-part housing

Abstract

A cell module (100) for storing electrical energy in a motor vehicle, comprising a multi-part housing (110) and cells (150) arranged within the housing (110), wherein the housing (110) is formed from a housing center part (120) and two end plates (130), and at least one of the end plates (130) is connected to the housing center part (120) by a plug connection, for which purpose the end plate (130) has several pins (131) and the housing center part (120) is formed with corresponding recesses (121) into which the pins (131) are pressed, characterized in that the end plate (130) is formed on its inner side with a circumferential projection (135) which bears circumferentially against the inner walls of the housing center part (120), wherein an adhesive bond between the end plate (130) and the housing center part (120) also takes place at the projection (135), and the adhesive used at the same time acts as a seal between the end plate (130) and the housing middle part (120).

Description

[0001] According to the preamble of claim 1, the invention relates to a cell module for storing electrical energy in a motor vehicle, comprising a multi-part housing and cells arranged within the housing.

[0002] Electrically rechargeable cells (battery cells) can be grouped into so-called cell modules. Such cell modules can then be installed individually or together with other cell modules (e.g., within a traction battery) in the vehicle. A cell module comprises a number of cells arranged in a housing, which may also include means for their mechanical fixation, electrical contact, and, if necessary, temperature control. The cells can be individual cells (e.g., lithium-ion cells) or cell arrays comprising several individual cells.

[0003] DE 10 2015 220 196 A1 describes a cell module for storing electrical energy, comprising a housing and cells arranged within the housing (i.e., inside the housing). The housing can be made of metal, for example, an aluminum sheet. In this case, the metal housing preferably consists of a container with a rectangular base and four side walls arranged at right angles to it, as well as a lid that has essentially the same shape and size as the base. The housing is therefore preferably cuboid in shape. The metal housing is usually closed by welding the edges of the lid to the opening edge of the container.

[0004] German patent DE 10 2013 021 332 A1 also describes a cell module comprising a housing and a number of cells arranged within the housing. The housing has two end-faced end elements. The connection between the housing and an end element is achieved by means of a material bond, e.g., gluing, welding, and / or a form-fit connection, e.g., crimping, and / or a force-fit connection, e.g., with pressed-in round, flat, or shaped gaskets.

[0005] From the nearest patent, US 2015 / 0221905 A1, a multi-part housing for a lithium-ion cell is known, consisting of a housing center section and two end plates. One of the end plates is equipped with pins and is snapped to the housing center section by means of these pins.

[0006] For the state of the art, reference is also made to JP 2012-248520 A, DE 10 2013 200 560 A1, DE 10 2016 001 145 A1, DE 10 2016 125 395 A1, US 7,479,758 B2 and EP 2 438 640 B1.

[0007] The invention is based on the objective of providing an improved cell module of this type for motor vehicle applications which does not have, or at least only has to a lesser extent, at least one disadvantage associated with the closest prior art.

[0008] The problem is solved by a cell module according to the invention with the features of claim 1. Further developments and embodiments of the cell module according to the invention are set out in the dependent claims, the following description of the invention and the figures.

[0009] The cell module according to the invention comprises a multi-part housing and cells (or at least one cell) arranged within this housing, the housing being formed from a housing center section and two end plates. According to the invention, at least one of the end plates, preferably both end plates, is connected to the housing center section by a plug connection or is attached to the housing center section by means of a plug-in fastening, for which purpose this end plate has several pins and the housing center section is designed with corresponding recesses into which the pins (of the end plate) are pressed.

[0010] A pin is understood in particular to be a projecting or protruding connecting element that has an excess in relation to the complementary or corresponding recess in the middle part of the housing, so that a press fit and thus a form-fit and force-fit connection is established.

[0011] During assembly of the cell module, the end plate can be attached or pressed onto the housing center section after the cells have been arranged inside the housing, enabling simple and cost-effective manufacturing of the cell module. Preferably, the pins are designed with chamfered edges or are conical to simplify pressing them into the recesses.

[0012] The press fits between the pins and the recesses are preferably designed to create a stable, firm, and, in particular, inseparable or very difficult-to-separate connection. (Tensile forces occurring during operation are so low that they can be easily withstood.) This eliminates the need for complex welding and / or bolting; that is, the fastening is weld- and / or bolt-free. Typical problems associated with welding (e.g., heat distortion and resulting tolerance errors, damage to seals and electrical insulation, electrical short circuits and / or ground faults due to weld spatter, etc.) cannot occur with the cell module according to the invention. Furthermore, a hybrid construction is possible; that is, the housing center section and the end plates can be made of different materials.

[0013] Preferably, the housing center section is cuboid in shape with a completely closed wall and can be manufactured in one piece from a hollow profile, in particular a multi-chamber hollow profile, or in multiple pieces from individual flat profiles, in particular multi-chamber flat profiles (which are joined together in a suitable manner, e.g., by bonding). The at least one end plate, connected to the housing center section by means of a plug connection, preferably has four pins arranged in its corners, and the wall of the housing center section is formed at least at the relevant axial ends or on the relevant end face with corresponding recesses or depressions into which the pins are pressed. Preferably, the housing center section is made of steel or aluminum, e.g., from at least one extruded aluminum profile, or of fiber-reinforced plastic (FRP), e.g., from at least one pultruded profile.Extruded and pultruded profiles can be supplied as semi-finished products by the meter and cut to the desired length.

[0014] Preferably, the end plate, including the pins, which is connected to the housing center part by means of a plug connection, is manufactured or formed in one piece and is in particular a die-cast part, e.g. made of aluminum or cast iron, or an injection-molded part made of plastic or fiber-reinforced plastic.

[0015] The end plate, connected to the housing's central section via a plug connection, can be equipped with at least one connection, at least one distributor or collector, and / or at least one overflow channel for cooling channels integrated into the housing's central section for cooling the cells. The cooling channels, through which coolant (or other cooling fluid) flows, are preferably integrated into the wall, for example, in the form of chambers (cavities) of a multi-chamber hollow profile. This can significantly simplify assembly.

[0016] The end plate, connected to the housing center section by means of a plug connection, can have at least one fastening element for securing the cell module (e.g., in a battery box). Such a fastening element is, for example, a screw hole or a threaded bore. Preferably, the cell module according to the invention is only attached to the end plates.

[0017] According to the invention, the end plate, which is connected to the housing center section by means of a plug connection, is formed on its inner side with a circumferential projection or similar feature that bears against the inner walls of the housing center section, preferably in an overlap area of ​​up to 10 mm. Transverse forces can also be transmitted via the projection, thereby supporting the end plate on the housing center section. Furthermore, the projection provides a bonding and sealing connection between the end plate and the housing center section, with the adhesive used simultaneously acting as a seal between the end plate and the housing center section.

[0018] The invention is explained in more detail below with reference to the figures. Fig. Figure 1 shows a cell module. Fig. Figure 2 schematically illustrates the connection according to the invention of an end plate with the housing middle part during the assembly of the cell module. Fig. Figure 3 shows a sectional view according to the one in Fig. 2 specified section path (AA).

[0019] The in Fig. 1. The cell module 100 shown has a dense and stable housing 110 and cells 150 arranged inside this housing (see figure). Fig. 3) The housing 110 consists of a cuboid housing center section 120 with a completely enclosed wall and two lid-like end plates 130. The housing center section 120 and the end plates 130 can be made of metal or plastic. The cells 150, which are protected inside the housing 110, are electrically interconnected and connected to external terminals 140.

[0020] According to the invention, both end plates 130, which can be identically designed, are firmly connected to the housing center part 120 via plug connections. This is shown in Fig. Figure 2 illustrates this. Each end plate 130 has four conically shaped pins or studs 131 arranged in its corners and projecting essentially perpendicularly from the top surface. When the end plate 130 is axially placed onto the respective end face of the housing center section 120, these pins or studs are pressed into corresponding recesses 121 in the corners of the housing wall. The pins 131 shown have a rectangular cross-section, but can also be designed with a different cross-section.

[0021] The housing center section 120 shown is constructed from several interconnected multi-chamber flat profiles, wherein the recesses 121 for receiving the oversized pins 131 are chambers (cavities) of these multi-chamber profiles. The housing center section 120 can also be manufactured in one piece from an extruded or pultruded profile, or from sheet metal and / or plastic parts, or a combination of profile, sheet metal, and plastic parts. The cover-like end plates 130 are manufactured in one piece from plastic or metal and are, in particular, die-cast or injection-molded parts.

[0022] The end plates 130 are equipped with one screw hole 132 or, if necessary, with several screw holes (see right end plate 130 in Fig. 1) designed to enable the cell module 100 to be attached or held in place on the end plates 130. The end plates 130 may also have other fastening elements, such as threaded holes, fastening grooves, screw-on tabs or flanges, and the like.

[0023] The central chambers 123 of the wall section 122 of the housing middle part 120, which serves as the housing base, are used as cooling channels for cooling the cells 150 and are designed to allow coolant flow. The end plates 130 can have integrated connections 133 as well as distributors or collectors and / or overflow channels 134 for the coolant, as shown in the figure. Fig. 2 and Fig. 3. Similarly, other wall sections of the housing center part 120 can also be designed with cooling channels.

[0024] Optionally, the base 122 can be reinforced, for example, as an underride guard (UGS). The end plates 130 can have additional pins or similar features, which, analogous to the preceding explanations, are pressed into recesses formed in this reinforcement. This creates a particularly stable and robust housing.

[0025] As from Fig. As can be seen in Figure 3, the end plates 130 are formed on their inner sides with a molded projection 135 or the like, which rests against the inner walls of the housing center section 120. These projections 135 are additionally bonded. The adhesive used also acts as a seal between the end plate 130 and the housing center section 120.

[0026] During assembly, the end plates 130 are pushed onto the end faces of the housing center section 120 until they reach their stop, thus forming full-surface contact with the housing center section 120. This allows operating forces, and especially crash forces, acting on the end plates 130 to be transferred directly into the housing center section 120 without affecting the press-fit connections on the pins 131 or the adhesive bonds on the projections 135. This significantly improves safety, particularly crash safety.

Claims

[1] Cell module (100) for storing electrical energy in a motor vehicle, comprising a multi-part housing (110) and cells (150) arranged within the housing (110), wherein the housing (110) is formed from a housing center part (120) and two end plates (130) and at least one of the end plates (130) is connected to the housing center part (120) by a plug connection, for which purpose the end plate (130) has several pins (131) and the housing center part (120) is formed with corresponding recesses (121) into which the pins (131) are pressed, characterized by , that the end plate (130) is formed on the inside with a circumferential projection (135) which rests circumferentially against the inner walls of the housing middle part (120), wherein an adhesive bond also takes place between the end plate (130) and the housing middle part (120) at the projection (135) and the adhesive used simultaneously acts as a seal between the end plate (130) and the housing middle part (120). [2] Cell module (100) according to claim 1, characterized by , that the pins (131) are designed with insertion chamfers or are conical. [3] Cell module (100) according to claim 1 or 2, characterized by , that the housing center part (120) is cuboid in shape with a completely closed wall and is made from a hollow profile or from individual flat profiles. [4] Cell module (100) according to any one of the preceding claims, characterized by , that the end plate (130), including the pins (131), is manufactured in one piece and is in particular a die-cast or injection-molded part. [5] Cell module (100) according to any one of the preceding claims, characterized by , that the end plate (130) is designed with at least one connection (133), at least one distributor (134) and / or at least one overflow channel (134) for cooling channels (123) integrated in the housing middle part (120) for cooling the cells (150). [6] Cell module (100) according to any one of the preceding claims, characterized by , that the end plate (130) is designed with at least one fastening element (132) for fastening the cell module (100).

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