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DE-102024128456-B4 - Accumulator with at least one cylindrical battery cell

DE102024128456B4DE 102024128456 B4DE102024128456 B4DE 102024128456B4DE-102024128456-B4

Abstract

The invention relates to an accumulator with at least one cylindrical battery cell (2) having an end face (3) which has a central first contact surface (4) forming a region of a first electrical pole (5) and a second contact surface (7) circumferentially surrounding the end face (3) forming a region of a second electrical pole (6) and with a contact plate (18) with which the at least one battery cell (2) is contacted at the end face (3) and which has spring-elastic contact tongues (21, 22) and at least one spring-elastic contact tongue (21, 22) is assigned to the first and second contact surfaces (4, 7) of the at least one battery cell (2) and the contact tongues (21, 22) contact the first and second contact surfaces (4, 7) under spring tension.

Inventors

  • Carlo Schmid

Assignees

  • SECOND RIDE GMBH

Dates

Publication Date
20260513
Application Date
20241001

Claims (16)

  1. Accumulator with at least one cylindrical battery cell (2) having an end face (3) having a central first contact surface (4) forming a region of a first electrical pole (5) and a second contact surface circumferentially surrounding the end face (3). che (7) which forms a region of a second electrical pole (6) and is connected to a contact plate (18) with which the at least one battery cell (2) is contacted at the end face (3) and which has spring-elastic contact tongues (21, 22) and which is assigned to the first and second contact surfaces (4, 7) of the at least one battery cell (2) and which has at least one spring-elastic contact tongue (21, 22) and which is assigned to the first and second contact surfaces (4, 7) and which contact tongues (21, 22) contact the first and second contact surfaces (4, 7) under spring tension, wherein the contact tongues (21, 22) assigned to a battery cell are electrically insulated from each other in the contact plate (18) and wherein the contact tongues (21, 22) form a force-fit connection with the first and second contact surfaces (4, 7).
  2. accumulator after Claim 1 , characterized in that the accumulator has a plurality of battery cells (2), and at least one spring-elastic contact tongue (21, 22) is assigned to at least one of the battery cells (2) at the first and second contact surfaces (4, 7) and the contact tongues (21, 22) contact the first and second contact surfaces (4, 7) under spring tension.
  3. accumulator after Claim 1 or 2 , characterized in that the first electrical pole (5) is a positive pole and the second electrical pole (6) is a negative pole.
  4. Accumulator according to one of the preceding claims, characterized in that the at least one battery cell (2) has an end face (3) and an opposite end face (10) along a longitudinal extension (L).
  5. Accumulator according to one of the preceding claims, characterized in that the first contact surfaces (4) and second contact surfaces (7) form outermost surfaces along the end face (3) in longitudinal extent (L).
  6. Accumulator according to one of the preceding claims, characterized in that the circumferential second contact surfaces (7) are designed as circumferential edges of a battery cell casing.
  7. Accumulator according to one of the preceding claims, characterized in that one or more contact tongues are formed as U-shaped, E-shaped, Ω-shaped, H-shaped, double-I-shaped or M-shaped cut lines (15) from the contact board (18).
  8. Accumulator according to one of the preceding claims, characterized in that conductive projections (23, 24) are arranged on one of the sides of the contact tongues (21, 22) facing at least one battery cell (2), which, under spring force, each establish contact with the second contact surface (7) or the first contact surface (4).
  9. Accumulator according to one of the preceding claims, characterized in that higher contact surfaces in longitudinal extent (L) protrude further from the end face (3) than lower contact surfaces and contact tongues (21, 22) with longer spring arms are assigned to the higher contact surfaces than to the lower contact surfaces.
  10. Accumulator according to one of the preceding claims, characterized in that higher contact surfaces in longitudinal extent (L) protrude further from the end face (3) than lower contact surfaces and contact tongues (21, 22) with higher elevations (23, 24) are assigned to the lower contact surfaces than to the higher contact surfaces.
  11. Accumulator according to one of the preceding claims, characterized in that a cell positioner (16) is provided in a section of the end faces (3) of the battery cells (2), which brings the battery cells (2) to defined positions relative to each other and to the contact board (18).
  12. accumulator after Claim 11 , characterized in that openings (17) are provided in the cell positioner (16) through which contact tongues (21, 22) are guided onto the contact surfaces (4, 7) of one of the battery cell (2).
  13. accumulator after one of the Claims 11 or 12 , characterized in that the cell positioner (16) has individual separate cell positioner elements which are arranged on the side of the contact board (18) facing the battery cells (2).
  14. Accumulator according to one of the preceding claims, characterized in that a top plate (11) is provided for pressure distribution with ribs (28) arranged on the battery side and the contact tongues (21, 22) are arranged in a row in the contact plate (18) and a free strip (29) is formed between rows of contact tongues, on which the ribs (28) press.
  15. Accumulator according to one of the preceding claims, characterized in that the at least one battery cell (2) is arranged with the opposite end face (10) on a base plate (12) and a thermal coupling is present between the opposite end faces (10) and/or cladding surfaces and the base plate (12).
  16. accumulator after Claim 15 , characterized in that an electrically insulating layer (14) is provided between the base plate (12) and the opposite end faces (10), which is thermally conductive.

Description

The invention relates to a battery with at least one cylindrical battery cell. Rechargeable batteries typically contain a large number of cylindrical battery cells of the 18650 or 21700 form factor. Several methods exist for electrically connecting these battery cells. Usually, the battery cells are contacted from both sides. The terminals of the battery cells are joined using nickel foils in a spot-welding process. Groups of cells connected in parallel are oriented in the same direction, while groups connected in series are alternately rotated by 180 degrees so that the positive terminal of one group can be connected to the negative terminal of the next group via the shortest possible path. Wire bonding methods are also known, in which the battery cell is contacted on one side. These methods are disadvantageous in that the connection between the battery cell and the wires is a metallurgical bond, and if a battery cell fails, its replacement is unfortunately only possible with considerable manual labor. Furthermore, residues can be left behind, which make re-bonding more difficult. From the FR 3100929 B1 A battery pack consisting of battery cells contacted from opposite sides is known. Conventional printed circuit boards are used, and spherical solder segments are formed on contact tongues. These segments are pressed onto the cells with a defined contact force, creating a positive connection that transmits sufficient current to power the electrical load. This design has a disadvantage in that heat dissipation from the battery cells, which heat up over time, is primarily possible via the side walls of the cells, but no longer sufficiently via the end faces. The WO 2025/040667 A1 Disclosing a contacting device for connecting multiple battery cells, with two electrically isolated current paths and with receptacles for battery cell end sections, wherein a first conductor for the parallel electrical contacting of the positive poles of the battery cells forms the first current path, and a second conductor for the parallel electrical contacting of the negative poles forms the second current path. The object of the present invention is to provide an accumulator that reduces the aforementioned problems. The task is accomplished by an accumulator having the features of claim 1. The accumulator according to the invention has at least one cylindrical battery cell, which has an end face having a central first contact surface that forms a region of a first electrical pole and a second contact surface circumferentially around the outside of the end face, which forms a region of a second electrical pole and is connected to a contact plate with which the at least one battery cell is contacted at the end face and which has spring-elastic contact tongues and at least one spring-elastic contact tongue is assigned to the first and second contact surfaces of the at least one battery cell and the contact tongues contact the first and second contact surfaces under spring tension. Advantageously, the invention can be applied to a single battery cell. The at least one battery cell is preferably rechargeable. Preferably, the accumulator has a plurality of battery cells, each battery cell having an end face which has a central first contact surface forming a region of a first electrical pole and a second contact surface circumferentially surrounding the end face which forms a region of a second electrical pole and which has a contact plate with which the battery cells are contacted at the end face and the contact plate has spring-elastic contact tongues and at least one spring-elastic contact tongue is assigned to the first and second contact surfaces of at least some of the battery cells and the contact tongues contact the first and second contact surfaces under spring tension. Thus, the battery can be adapted to different requirements in terms of its power, voltage and current. Fortunately, the battery cells have the same design. This makes the battery simpler and cheaper to manufacture. The contact tongues form a frictional connection with the first and second contact surfaces. This means that the contact tongues press against the contact surface under spring force, but do not form a material bond with it. This frictional connection allows for easy maintenance of the accumulator, including the simple replacement of individual defective battery cells. Particularly preferred is the first electrical pole a positive pole and the second electrical pole a negative pole. This embodiment corresponds to commercially available battery cells and is therefore cost-effective. Advantageously, at least one battery cell has an end face and an opposite end face along a longitudinal dimension. The at least one battery cell can be of the 18650 or 21700 form factor. However, the invention is not limited to a specific size range for the battery cell or a particular form factor. The known forms 10440, 26650, and 4680 can also be used. Other forms are al