Battery terminal

Abstract

The invention relates to a terminal (1) for a starter battery (3) of a vehicle, comprising a terminal dome (5) and a terminal pin (7), wherein the terminal pin (7) is arranged in a concave recess of the terminal dome (5) and is electrically connected to the terminal dome (5) at its end face, characterized in that an electrical insulator element (9) is arranged in a gap between a lateral surface of the terminal pin (7) and the terminal dome (5).

Description

[0001] The invention relates to a connection terminal for a starter battery of a vehicle, a starter battery for a vehicle having at least one such connection terminal, a first method for producing such a connection terminal for a starter battery of a vehicle, and an alternative method for producing such a connection terminal for a starter battery of a vehicle.

[0002] A vehicle's starter battery, especially one that functions as a voltage source in the 12 V or 24 V range, typically has terminals that are designed in two parts. An outer part typically forms a terminal dome for connecting a vehicle's electrical cable, while an inner part is a terminal stud that leads to a battery terminal plate. The terminal stud is sometimes also called a socket pin.

[0003] In the state of the art, various designs of connection terminals for a battery are known: EP 3 701 577 A1 relates to a terminal for a rechargeable battery, wherein the terminal has a connection area for attaching a terminal clamp to the terminal, and a fastening area for attaching the terminal to a housing part of the rechargeable battery. In an end area of ​​the fastening area facing the connection area, a circumferential projection is provided, which has at least substantially a ring shape and is provided with teeth on its outer circumference for the purpose of securing the terminal against rotation.In order to ensure that no capillary gaps or gaps in the pm range occur between the connection pole and the material of the battery cover when the connection pole is pressed or injected into a battery cover of the accumulator, the invention provides that in the end region of the fastening region facing the connection region, between the circumferential projection provided with the toothing and the connection region, a circumferential sealing projection is provided, which is at least substantially circular in shape.

[0004] EP 3 133 674 B1 also relates to a battery sleeve for a battery, comprising a hollow body having an outer wall and an inner wall, wherein a fastening portion, a contact portion and a torque ring are provided on the outer wall between the fastening portion and the contact portion, wherein the outer wall preferably has at least one circumferential projection on the fastening portion, which forms a labyrinth, wherein the inner wall has at least an upper portion surrounded by the contact portion, and a lower portion surrounded by the fastening portion and has a widening diameter towards an underside of the battery sleeve, wherein the torque ring has a first portion which is aligned with a first circular planar support surface towards the contact portion, a third portion which is aligned with a second circular planar surface towards the fastening portion,and a second section between the first section and the third section having an outer contour with recesses, wherein the first section, the second section and the third section have the same diameter.,

[0005] EP 2 814 088 B1 also relates to a battery terminal with a hollow body having an outer wall and an inner wall, further comprising a mounting portion, a contact portion and a torque ring between the mounting portion and the contact portion, wherein the outer wall preferably has at least one labyrinth ring on the mounting portion, which forms a labyrinth, wherein the inner wall has at least an upper portion surrounded by the contact portion, a lower portion surrounded by the mounting portion and which, in a side sectional view, has a concave shape, and an edge between the upper portion and the one lower portion.

[0006] While the terminal dome is typically mounted on the terminal stud, one end of the terminal stud and one cover of the terminal dome are soldered (e.g., with lead) to create an electrically conductive connection from the terminal stud via the terminal dome to a vehicle's electrical line, a gap can be provided along a peripheral surface of the terminal stud to a peripheral shell of the terminal dome to compensate for manufacturing tolerances. The terminal dome is typically tightly connected to a housing during starter battery manufacturing.

[0007] If the terminal dome is subjected to excessive mechanical stress, for example, when applying an excessively high clamping force or tightening torque when attaching a vehicle's electrical cable, the gap can narrow. While such mechanical stress alone can deform the terminal dome to such an extent that the tight seal with the housing is damaged, the narrowing of the gap between the terminal dome and the terminal pin can, in particular, cause electrical flashover and thus electrically induced sparking. This, along with hydrogen escaping from the battery, can lead to local oxyhydrogen explosions. This can further damage the battery terminal pool and the tight connection between the terminal dome and the housing, even leading to electrolyte leakage from the battery.

[0008] The object of the invention is therefore to improve a battery connection terminal.

[0009] The invention is based on the features of the independent claims. Advantageous developments and refinements are the subject of the dependent claims.

[0010] A first aspect of the invention relates to a connection pole for a starter battery of a vehicle, comprising a connection dome and a pole pin, wherein the pole pin is arranged in a concave recess of the connection dome and is electrically connected to the connection dome at the end face, characterized in that an electrical insulator element is arranged in a gap between a lateral surface of the pole pin and the connection dome.

[0011] In contrast to a high-voltage battery in a battery-electric vehicle, the starter battery serves to supply the vehicle's subsystems, and in some cases, in a hybrid vehicle, to temporarily power the vehicle. For example, a vehicle with an internal combustion engine requires initial energy to start, which is typically obtained from such a starter battery. Typical starter batteries in passenger cars have a supply voltage of 12 V.

[0012] The terminal stud and the terminal dome together form the starter battery's terminal post. When installing the terminal post, the terminal stud is inserted into the cup-shaped opening of the terminal dome. The two-part design of the terminal post is convenient for assembly during battery manufacture, allowing the terminal dome to be sealed to a starter battery housing cover, while the terminal stud leads into the interior of the battery, particularly to a galvanic cell. When an electrical current flows under direct voltage, a charge flows from the interior of the battery through the terminal stud, across its front end, to the terminal dome, and from there via electrical lines to the vehicle's subsystems, or in the reverse direction.

[0013] For this purpose, the pole pin is electrically connected to the connection dome on the front side of the pole pin when the connection pole is finished, in particular soldered using an electrically conductive solder material, for example lead.

[0014] However, there is an intentional gap between the outer surface of the terminal pin of a conventional connection post and the side walls of the connection dome, which at least partially enclose the outer surface of the terminal pin. The gap serves to compensate for manufacturing tolerances of the terminal pin and connection dome. The gap is harmless during normal battery operation; however, if excessive mechanical stress occurs on the connection dome, such as due to misuse, the gap can close to excessively small gaps or close completely. Especially with very small gaps, electrical arcing and thus sparking can occur. These sparks can ignite gaseous hydrogen that may escape from the battery's galvanic element under the influence of atmospheric oxygen.This effect, in particular, often leads to damage to the terminal dome, especially the contact surface of the terminal dome with the starter battery housing. Battery electrolytes, especially acid, can leak out there and cause acid corrosion.

[0015] As a countermeasure, the invention provides an electrical insulator element in the gap between the outer surface of the pole pin and the section of the terminal dome surrounding the outer surface. The electrical insulation between the outer surface of the pole pin and the terminal dome prevents electrical jumps and thus also prevents sparking.

[0016] If the electrical insulator element is advantageously made of a ductile material such as a malleable plastic, the function of compensating for manufacturing tolerances is further maintained. Furthermore, if the terminal dome is plastically deformed due to external mechanical stress, such a ductile material can yield to these deformations and, to a certain extent, participate in the deformation without damage and without losing its electrical insulation properties.

[0017] According to an advantageous embodiment, the electrical insulator element is a plastic sheathing around a circumference of the outer surface of the pole pin. Preferably, the plastic sheathing extends at least partially around the entire circumference of the outer surface of the pole pin.

[0018] According to a further advantageous embodiment, the electrical insulator element is a plastic sheath that can be pushed onto the outer side of the terminal stud and has the shape of a hollow truncated cone or hollow truncated cylinder. The shape of the plastic sheath is advantageously adapted to the shape of the terminal stud. The sleeve shape of the plastic sheath facilitates installation on the terminal stud as long as the terminal stud and terminal dome are not yet attached to one another.

[0019] According to a further advantageous embodiment, the electrical insulator element is made of a material from the group of silicones.

[0020] According to a further advantageous embodiment, the electrical insulator element is made of thermoplastic material.

[0021] A further aspect of the invention relates to a starter battery for a vehicle having at least one connection pole as described above and below.

[0022] Advantages and preferred developments of the proposed starter battery result from an analogous and analogous transfer of the statements made above in connection with the proposed connection pole.

[0023] A further aspect of the invention relates to a method for producing a connection terminal for a starter battery of a vehicle, comprising the steps: - applying an electrical insulator element to a lateral surface of a pole pin, and - Arranging the pole pin in a concave recess of a terminal dome so that a gap between the outer surface of the pole pin and the terminal dome is electrically insulated.

[0024] According to a further advantageous embodiment, a plastic pipe section or a plastic hose section is used as the electrical insulator element.

[0025] A further aspect of the invention relates to a method for producing a connection terminal for a starter battery of a vehicle, comprising the steps: - arranging a pole pin in a concave recess of a connection dome, and - Inserting an electrical insulator element into a remaining gap between a surface of the pole pin and the connection dome, so that the gap between the outer surface of the pole pin and the connection dome is electrically insulated.

[0026] According to a further advantageous embodiment, the electrical insulator element is produced by injecting softened plastic material into a gap between the pole pin and the connection dome.

[0027] Advantages and preferred developments of the proposed method result from an analogous and analogous transfer of the statements made above in connection with the proposed connection pole.

[0028] Further advantages, features, and details will become apparent from the following description, which – where appropriate with reference to the drawings – describes at least one embodiment in detail. Identical, similar, and / or functionally equivalent parts are provided with the same reference numerals.

[0029] They show: Fig. 1: A schematic connection terminal according to the state of the art. Fig. 2: A schematic connection pole according to an embodiment of the invention. Fig. 3: An exemplary detailed connection pole according to the state of the art. Fig. 4: An exemplary detailed connection pole according to an embodiment of the invention. Fig. 5: A starter battery according to an embodiment of the invention. Fig. 6: A method for producing a terminal pole according to an embodiment of the invention. Fig. 7: A method for producing a terminal pole according to another embodiment of the invention.

[0030] The representations in the figures are schematic and not to scale.

[0031] Fig. Figure 1 shows a prior art terminal post 1 for a starter battery 3 of a vehicle. A terminal dome 5 surrounds a terminal stud 7. The terminal stud 7 and terminal dome 5 are shown in section. The terminal stud 7 is cylindrical, and the terminal dome 5 surrounds the terminal stud 7 around its entire circumference. At one end of the terminal stud, the terminal stud 7 is electrically connected to a cover surface of the terminal stud 5 by soldering. A gap is provided between the outer surface of the terminal stud 7 and the outer wall of the terminal dome 5 to accommodate manufacturing tolerances.

[0032] Fig. 2 shows a modified terminal 1 as shown in Fig. 1. Since the gap between the connection dome 5 and the pole pin 7 can decrease if the connection dome 5 is damaged or if the connection is damaged, electrical charges could flow at contact surfaces or approaching surfaces between the connection dome 5 and the pole pin 7 outside the front soldering surface. To prevent this, an electrical insulator element 9 is arranged in the gap between the outer surface of the pole pin 7 and the connection dome 5. This insulator element 9 is made of plastic and can be inserted into the location of the future gap when the pole pin 7 is mounted on the connection dome 5. The outer surface of the pole pin 7 is thus electrically insulated from the surrounding outer wall of the connection dome 5.

[0033] Fig. 3 and Fig. 4 show more detailed embodiments of a connection pole 1 as in the Fig. 1 and Fig. 2. The pole pin 7 is shown complete, the connection dome 5 is shown cut open. Analogously, Fig. 3 shows a connection terminal 1 according to the prior art. The terminal pin 7 is connected to a terminal plate of the battery on its underside. A thread at the lower end of the casing wall of the connection dome 5 serves to mount the connection dome 5 to a battery casing. A plastic cap is provided on the connection dome 5. Fig. 3 there is still a gap between the pole pin 7 along its truncated cone-shaped surface to the surface surrounding the wall of the connection dome 5. In Fig. 4, a truncated cone-shaped electrical insulator element 9 made of plastic is therefore applied to the pole pin 7, adapted to the contour of the outer surface of the pole pin 7, so that this electrically insulates the outer surface of the pole pin 7 from the outer wall of the connection dome 5.

[0034] Fig. 5 shows a starter battery 3 for a vehicle with at least one terminal 1 according to Fig. 2 or Fig. 4.

[0035] Fig. 6 shows a method for producing a terminal post 1 for a starter battery 3 of a vehicle. In a first step S1, an electrical insulator element 9 is applied to a peripheral surface of a terminal stud 7. The electrical insulator element 9 is made from a piece of plastic tubing and can be applied to the terminal stud 7. Remaining thereon, in the second step S2, the terminal stud 7 is inserted from below into the hollow opening of the terminal dome 5. As a result, the electrical insulator element 9 encloses the cylindrical terminal stud 7 and electrically insulates it from a peripheral wall of the terminal dome 5.

[0036] Fig. Figure 7 shows an alternative method to that of Fig.6, which is carried out to produce a connection terminal 1 for a starter battery 3 of a vehicle. In the first step H1, a pole pin 7 is arranged in a concave recess of a connection dome 5. In the second step H2, an electrical insulator element 9 is introduced into the gap provided between the connection dome 5 and the pole pin 7, filling the gap by injecting heat-softened thermoplastic into the gap. Alternatively, two-component plastic is used, which hardens in the gap. Regardless of the method, the result is that the electrical insulator element 9 electrically insulates the gap between the outer surface of the pole pin 7 and a outer wall of the connection dome 5, so that even if the connection dome 5 is mechanically deformed, electrical current only reaches the connection dome 5 through the end face of the pole pin 7.

[0037] Although the invention has been illustrated and explained in detail by preferred embodiments, the invention is not limited by the disclosed examples, and other variations may be derived therefrom by those skilled in the art without departing from the scope of the invention. It is therefore clear that a multitude of variations exist. It is also clear that the embodiments mentioned by way of example are truly only examples and should not be construed as limiting the scope, possible applications, or configuration of the invention in any way.Rather, the preceding description and the description of the figures enable the person skilled in the art to implement the exemplary embodiments in concrete terms, whereby the person skilled in the art, with knowledge of the disclosed inventive concept, can make various changes, for example with regard to the function or the arrangement of individual elements mentioned in an exemplary embodiment, without departing from the scope of protection defined by the claims and their legal equivalents, such as further explanations in the description. List of reference symbols 1 connection pole 3 starter battery 5 connection dome 7 pole pins 9 Insulator element H1 Arrange H2 introduction S1 Application S2 Arrange QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] EP 3 701 577 A1

[0003] EP 3 133 674 B1

[0004] EP 2 814 088 B1

[0005]

Claims

[1] Connection terminal (1) for a starter battery (3) of a vehicle, comprising a connection dome (5) and a terminal pin (7), wherein the terminal pin (7) is arranged in a concave recess of the connection dome (5) and is electrically connected to the connection dome (5) at the end face, characterized by that an electrical insulator element (9) is arranged in a gap between a lateral surface of the pole pin (7) and the connection dome (5). [2] Terminal pole (1) according to claim 1, wherein the electrical insulator element (9) is a plastic sheath around a circumference of the lateral surface of the pole pin (7). [3] Connection pole (1) according to claim 2, wherein the electrical insulator element (9) is a plastic sheath that can be pushed onto the jacket side of the pole pin (7) and has the shape of a hollow truncated cone or hollow truncated cylinder. [4] Connection pole (1) according to one of claims 1 to 3, wherein the electrical insulator element (9) is made of a material from the group of silicones. [5] Connection pole (1) according to one of claims 1 to 3, wherein the electrical insulator element (9) is made of thermoplastic material. [6] Starter battery (3) for a vehicle with at least one connection pole (1) according to one of the preceding claims. [7] Method for producing a connection terminal (1) for a starter battery (3) of a vehicle, comprising the steps: - applying (S1) an electrical insulator element (9) to a lateral surface of a pole pin (7), and - Arranging (S2) the pole pin (7) in a concave recess of a connection dome (5) so that a gap between the outer surface of the pole pin (7) and the connection dome (5) is electrically insulated. [8] Method according to claim 7, wherein a plastic pipe section or a plastic hose section is used as the electrical insulator element (9). [9] Method for producing a connection terminal (1) for a starter battery (3) of a vehicle, comprising the steps: - arranging (H1) a pole pin (7) in a concave recess of a connection dome (5), and - introducing (H2) an electrical insulator element (9) into a remaining gap between a lateral surface of the pole pin (7) and the connection dome (5), so that the gap between the lateral surface of the pole pin (7) and the connection dome (5) is electrically insulated. [10] Method according to claim 9, wherein the electrical insulator element (9) is produced by injecting softened plastic material into a gap between the pole pin (7) and the terminal dome (5).

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