阅读说明：本技术 用于可拆卸地接触电池单元的装置 (Device for detachably contacting a battery cell ) 是由 G.瓦尔德舒茨 W.施穆德梅尔 F.德雷克斯勒 P.多布施 于 2020-02-25 设计创作，主要内容包括：在此描述了一种用于将电池单元(4)与反向于连接方向(2)敞开的单元容纳部可拆卸地相接触的装置,所述单元容纳部由接触弹簧底座(1)限定边界,用于在外壳侧围绕电池单元(4)的接触舌片(3)反向于连接方向(2)地从所述接触弹簧底座突伸出。为了提供一种用于可拆卸地接触电池单元(4)的装置,即使在周期性的机械负荷下,该装置也能够与所安装的电池单元的相对位置无关地并且尽可能与电池单元的直径无关地实现可靠的电连接,而不使组装过程变难,在此建议,所述接触舌片(3)具有沿径向突出到单元容纳部中的切割的卵形形式的接触体(5)。(A device for detachably contacting a battery unit (4) with a unit receptacle which is open opposite a connecting direction (2) and is delimited by a contact spring base (1) from which a contact tongue (3) which surrounds the battery unit (4) on the housing side projects opposite the connecting direction (2) is described. In order to provide a device for detachably contacting a battery unit (4), which, even under cyclic mechanical loading, makes it possible to achieve a reliable electrical connection independently of the relative position of the installed battery unit and as far as possible independently of the diameter of the battery unit, without making the assembly process difficult, it is proposed that the contact tongues (3) have contact bodies (5) in the form of cut ovals which project radially into the unit receptacles.)

1. A device for detachably contacting a battery unit (4) with a unit receptacle which is open opposite a connecting direction (2), the unit receptacle being delimited by a contact spring base (1) for a contact tongue (3) which protrudes from the contact spring base opposite the connecting direction (2) on the housing side around the battery unit (4), characterized in that the contact tongue (3) has a contact body (5) in the form of a cut oval which protrudes radially into the unit receptacle.

2. Device according to claim 1, characterized in that the contact body (5) is extruded from the contact tongue (3).

3. Device according to one of claims 1 or 2, characterized in that the edge of the contact spring base (1) is bent up to form a standing seam (10) with which the contact tongue (3) is connected.

4. Device according to one of claims 1 to 3, characterized in that the contact tongues (3) are convexly curved away from the unit receptacle, wherein the contact bodies (5) are arranged in the region of the apex of the curve in each case.

Technical Field

The invention relates to a device for detachably contacting a battery unit with a unit receptacle which is open opposite to a connecting direction and is delimited by a contact spring base for protruding from the contact spring base on the housing side, opposite to the connecting direction, around a contact tongue of the battery unit.

Background

A contact spring for contacting two battery cells in series is known from EP 3096372 a 1. The contact springs have contact tongues which surround the first battery cell and connect the first battery cell to the second battery cell in a bonded manner. In particular for large, unevenly designed battery cells or battery cells poorly mounted in contact springs, the contact tongues cannot exert a sufficiently large clamping force on the housing of the battery cell, which is why a sufficiently reliable contact of a high-capacity battery cell with a large diameter, for example a circular battery cell of the 21700 type, cannot be ensured under dynamic mechanical loading. A further disadvantage is that, due to the sharp-edged design of the contact tongues, when the battery cell is inserted into the cell receptacle delimited by the contact tongues and in the event of possible relative displacement of the battery cell in precisely this cell receptacle, progressive damage to the possibly present oxidation protection coating of the battery cell housing and/or the contact tongues themselves results. Furthermore, variable contact resistances occur due to the varying contact surface between the contact tongues and the cell housing, which leads to unfavorable electrical operating conditions. A material-bonded connection between the contact spring and the battery cell is therefore generally preferred.

In order to achieve a bonded connection even in the case of contact locations which can only be accessed with difficulty, (US 6120564, EP 2087554 a1, EP 2048723 a1, JP 2003077453 a) have therefore already proposed that solder points be provided on the contact springs, which enable a bonded connection when a correspondingly high current is applied. However, it is understandably disadvantageous that the current and temperature occurring at the time of welding may cause damage to the battery cell, in addition to limitations on assembly and lack of replaceability of the damaged battery cell.

Disclosure of Invention

The object of the invention is therefore to propose a device for detachably contacting battery cells, which device, even under cyclic mechanical loading, makes it possible to achieve reliable electrical connections regardless of the relative position of the installed battery cells and, as far as possible, regardless of the diameter of the battery cells, without the assembly process becoming difficult.

The object is achieved according to the invention in that the contact tongues have contact bodies in the form of cut ovals which project radially into the cell receptacles. In contrast to contact springs known from the prior art, which have an undefined contact surface with the battery cell surrounded by the opening, the contact surface between the contact tongue and the housing is provided in advance by a cut oval, preferably hemispherical contact body provided according to the invention, so that a defined contact resistance is produced between the contact body or the contact tongue and the battery cell. The contact resistance is largely constant even if the device undergoes periodic mechanical deformation due to vibration. Furthermore, owing to the rounded surfaces of the contact bodies, surface damage can be avoided, in particular because the contact bodies separate the sharp-edged contact tongues from the corresponding housing surface of the battery cell.

The contact body is extruded from the contact tongue, thereby resulting in an improved electrical contact and at the same time simple production conditions. The contact body can thus be produced in one working step, wherein a rounded surface for avoiding surface damage can be achieved without separate reworking. In order to reduce the electrical resistance caused by electrical contamination, the contact body may be provided with an oxidation-resistant coating. Such a coating is produced in a particularly advantageous embodiment of the invention in that the contact tongues are already provided with a coating thickness which is sufficient for the person skilled in the art before the contact body is extruded, so that the contact body surfaces which project into the cell receptacles after deformation have a complete oxidation-protection coating. Nickel or gold, for example, may be used as a coating for oxidation protection to reduce electrical resistance due to electrical contamination.

In order to be able to use the device according to the invention even for battery cells degassed at the bottom of the battery cell and to improve at the same time a secure mounting of the battery cell in the cell receptacle, it is proposed that the edge of the contact spring base is bent up to a standing seam (Stehfalz) to which the contact tongues are connected. The standing seam surrounds the end section of the cell housing, so that gas flowing out of the bottom side of the cell is prevented from flowing out laterally between the contact tongues and can be guided to a degassing channel provided for this purpose, which is connected to an opening provided for this purpose in the contact spring seat. At the same time, the standing seam reinforces the contact spring base and the contact tongues connected thereto, so that the clamping force of the contact tongues on the cell housing can be increased despite possible openings for discharging hot gases flowing out of the cell. The electrical conductivity is thus also increased, which increases in proportion to the normal contact force delivered by the contact body. The openings for discharging the hot gases flowing out of the battery cells can also be formed, for example, by meandering or spiral-shaped connecting conductors connected to the contact spring base, which enable a series connection to further battery cells.

In order to be able to insert the battery cell gently into the device even in the case of large clamping forces exerted by the contact tongues, it is expedient in a particularly useful embodiment of the device according to the invention for the contact tongues to be curved convexly away from the cell receptacle, wherein the contact bodies are each arranged in the region of the apex of the curve. As a result of these measures, a particularly efficient transmission of the clamping force generated by the contact tongues can be achieved, since the normal contact force acting on the battery cell housing is maximized and the shrinkage resistance (engewanderstand) is minimized. Although the rigidity of the contact tongues is increased by the bending according to the invention, the insertion process of the battery cell is facilitated by the cross section of the cell holder enclosed by the contact tongues widening behind the apex opposite to the connecting direction.

Drawings

The technical solution of the invention is exemplarily shown in the drawings. In the drawings:

fig. 1 shows a side view of a device according to the invention, which electrically connects two battery cells to one another; and

fig. 2 shows an enlarged perspective view of an embodiment of the device according to the invention.

Detailed Description

The device according to the invention has a contact spring base 1 with a contact tongue 3 projecting from the contact spring base 1 counter to the connecting direction 2. In order to surround and electrically connect the first battery cells 4 shown in fig. 1, the contact tongues 3 are arranged on the circumferential side of the contact spring base 1 and thus form cell receptacles which are open opposite the connection direction 2. The first battery unit 4 is detachably connected to the device via the contact tongues 3, whereby on the one hand a tolerance compensation is obtained under periodic mechanical operating conditions, which can be achieved by a relative movement of the battery unit 4 with respect to the unit receptacle, and on the other hand the assembly process is facilitated when the battery unit 4 is inserted into the unit receptacle. In order to ensure reliable and uniform contact in operation despite the detachable connection, the contact tongue 3, as can be seen preferably from fig. 2, has contact bodies 5, which are oval in shape, on the battery housing side and are arranged in the region of the apex of the curve of the contact tongue 3. This special geometry results in an approximately uniform contact surface on all contact tongues 3, regardless of the relative position of the battery cell 4 with respect to the cell holder. Since the oval contact body 5 is produced by a pressure forming process, for example by stamping, damage to possible pre-coatings can be prevented, so that the life cycle of the battery 4 is significantly extended.

If the device is used to contact two battery cells 4, 6 in series, a meandering connecting conductor 7 can be sprung from the contact spring base 1, which has an electrode receptacle 9 that surrounds the electrode 8 of the battery cell 6 on the circumferential side in order to achieve a bonded connection to the second battery cell 6. Due to the meandering configuration of the connecting conductor 7, which is visible in particular in fig. 2, a mechanical tolerance compensation can be achieved along and against the connecting direction 2, wherein the narrower webs of the connecting conductor 7 simultaneously serve as fuses in the event of an overcurrent.

If the contact tongues 3 have a rounded narrowing counter to the connecting direction 2 and a convex curvature with respect to the battery cells 4 toward the cell receptacle, so that in particular the edges of the contact spring base 1 are bent upwards into standing seams 10, a sufficiently high clamping force for reliable contacting can be generated even for battery cells of large dimensions, as a result of which particularly gentle connecting conditions result. The standing seam 10 advantageously connects to the battery cell 4 in a form-fitting manner, so that possible degassing flows escaping from the bottom side of the battery cell 4 can be prevented from escaping from the side. In order to also be able to achieve a material-bonded connection between the electrode 8 and the electrode receptacle 9 of the battery cell 6 that is as process-reliable as possible, the electrode receptacle 9 has calibration tabs 11 arranged on the circumferential side, which can be used, for example, as stop surfaces for a soldering iron (Schwei β kolben) for adjustment purposes.