Battery cell

Abstract

The invention relates to a battery cell having a cell housing (3) and a cell terminal, preferably an external contact element (11). According to the invention, at least one heat transfer means is disposed between the cell terminal, preferably the external contact element (11), and the cell housing (3), the external contact element (11) being connected to the cell housing (3) preferably thermally conductively via the heat transfer means and preferably electrically insulatingly.

Description

[0001] Description

[0002] Battery cell

[0003] The invention relates to a battery cell according to the preamble of claim 1.

[0004] A typical battery cell heats up during charging and discharging, primarily in the area of ​​the cell core. However, particularly under higher current loads and due to ohmic losses in a cell terminal of the battery cell, the battery cell can also heat up considerably in the area of ​​the cell terminal, in some cases even more than in the cell core. Since the cell terminal is thermally connected to the cell nucleus, heat can be transferred from the cell terminal to the cell nucleus. This causes the area of ​​the cell nucleus near the terminal - as well as the cell terminal - to heat up considerably, and a so-called hot spot forms, which increases the charging time required to fully charge the battery cell. The battery cell therefore has the disadvantage that the resulting hot spot reduces the charging performance of the battery cell.

[0005] A cell module is known from DE 10 2016223 063 A1.

[0006] An object of the invention is to provide a battery cell which has a higher charging performance compared to a known battery cell.

[0007] This object is achieved by the features of the independent claim. Preferred developments of the invention are disclosed in the subclaims.

[0008] According to the invention, a battery cell is proposed with a cell housing and a cell terminal, preferably an external contact element. According to the invention, at least one heat-conducting means is arranged between the cell terminal, preferably the external contact element, and the cell housing, wherein it is preferably provided that the external contact element is connected to the cell housing via the heat-conducting means in a heat-conducting and preferably electrically insulating manner. This has the advantage that heat is transferred from the cell terminal, preferably from the external contact element, to the cell housing via the heat-conducting means. This can prevent the formation of a hot spot in the region of a cell core of the battery cell near the terminal. As a result, the charging performance of the battery cell is increased in a structurally simple manner.The heat is then transferred from the cell casing to cooling plates of a cooling system for the battery cell, with the cooling plates being in thermally conductive contact with the cell casing.

[0009] In order to obtain a battery cell that is easy to manufacture in terms of production technology, it can be provided, for example, that the external contact element and / or an insulating element of the battery cell is and / or is part and / or parts of a cell terminal of the battery cell, and / or that the external contact element is connected via a connecting element, preferably a connecting bolt, preferably electrically, to the cell core of the battery cell, preferably an electrode of the battery cell, preferably the cell core.

[0010] In order to reliably protect a cell core of the battery cell, preferably electrodes of the cell core, from mechanical influences, it can preferably be provided that the cell housing delimits a housing interior to the outside, wherein it is preferably provided that the cell core, preferably one or more electrodes of the battery cell, is arranged in the housing interior.

[0011] For reliable electrical insulation, simplified assembly of the battery cell and to ensure that no electrical current flows between the cell housing and the insulating element, it can be provided in an exemplary embodiment that the battery cell has an insulating element and that the insulating element, preferably for insulation against electrical current flow, is arranged between the cell housing and the external contact element, and that a first opening and / or a second opening is assigned to the insulating element.

[0012] To promote the mechanical stability of the insulating element, it can preferably be provided that the first opening and / or the second opening are each delimited to the outside by the insulating element. For example, it can be provided that the first opening and / or the second opening each have the geometry of a circular cylinder or a cuboid.

[0013] In order for the cell terminal to take up as little installation space as possible, it can be provided, for example, that the insulating element is essentially U-shaped in cross-section and / or that the insulating element is essentially trough-shaped. In order to enable a defined heat transfer between the external contact element and the cell housing in a structurally simple manner, it can be provided in a specific embodiment that the heat conducting means is formed at least partially by a first breakthrough heat conducting material and / or by a second breakthrough heat conducting means, wherein it is provided that the first breakthrough heat conducting material is arranged in the first opening and / or wherein it is provided that the second breakthrough heat conducting material is arranged in the second opening.

[0014] For the most effective and efficient heat transfer possible, it can be provided in an exemplary embodiment that the external contact element is preferably directly in contact and / or, preferably directly, thermally conductive and / or, preferably directly, electrically insulating with the first breakthrough heat conducting means and / or the second breakthrough heat conducting means, and / or that the cell housing, preferably a cover of the cell housing, is preferably directly in contact and / or, preferably directly, thermally conductive and / or, preferably directly, electrically insulating with the first breakthrough heat conducting means and / or the second breakthrough heat conducting means.

[0015] In order for the battery cell to be easily integrated into a cell stack or into a network of battery cells, it can be provided in an exemplary embodiment that the battery cell has a cell connector, wherein it is provided that the cell connector is electrically connected, preferably directly, to the cell terminal, preferably the external contact element, and / or wherein it is provided that the cell connector is electrically connected, preferably directly, to a connecting element of the battery cell.

[0016] In order to enable not only heat transfer between the cell terminal and the cell housing, but also, in a structurally simple manner, additionally or alternatively also heat transfer from the cell connector to the cell housing, in a specific embodiment it can be provided that the heat conducting means is formed at least partially by a first connector heat conducting means and / or by a second connector heat conducting means, wherein it is provided that the first connector heat conducting means and / or the second connector heat conducting means is arranged between the cell connector and the cell housing, preferably a cover of the cell housing, wherein it is preferably provided that the cell connector is connected to the cell housing, preferably a cover of the cell housing, in a heat-transferring and preferably electrically insulating manner via the first connector heat conducting means and / or via the second connector heat conducting means.In order to make the cell connector particularly easy to manufacture, a preferred embodiment can provide for the cell connector to have a base section and a first leg and / or a second leg, wherein it is preferably provided that the base section lies flat against the external contact element, and / or wherein it is preferably provided that the first leg and / or the second leg protrudes and / or protrudes from the base section, preferably at right angles to a longitudinal axis of the connecting element of the battery cell, in the direction of the cell housing, preferably a cover of the cell housing.

[0017] In order to achieve the heat transfer from the cell connector to the cell housing in a structurally particularly simple manner, in an exemplary embodiment it can be provided that the first leg has a front surface which faces the cell housing, preferably a cover of the cell housing, and that the first connector heat conduction means is arranged between the front surface of the first leg and the cell housing, preferably a cover of the cell housing, and / or that the second leg has a front surface which faces the cell housing, preferably a cover of the cell housing, and that the second connector heat conduction means is arranged between the front surface of the second leg and the cell housing, preferably a cover of the cell housing.

[0018] In order to reliably prevent the connector heat conducting means from slipping relative to the cell connector, in an exemplary embodiment, a first collar of the first leg adjoins the front surface of the first leg in the direction of the cell housing, preferably a cover of the cell housing, wherein it is provided that an inner side of the first collar of the first leg, together with the front surface of the first leg, outwardly delimits a first receiving pocket in which the first connector heat conducting means is at least partially arranged, and / or that a second collar of the second leg adjoins the front surface of the second leg in the direction of the cell housing, preferably a cover of the cell housing, wherein it is provided that an inner side of the second collar of the second leg, together with the front surface of the second leg, outwardly delimits a second receiving pocket,in which the second connector thermal conduction means is at least partially arranged.,

[0019] In order to achieve particularly effective, efficient heat transfer at low cost, it can be provided in a specific embodiment that the heat conducting means is formed by a heat conducting mat and / or by a, preferably curable and / or cured, heat conducting paste, and / or the first breakthrough heat conducting means and / or the second breakthrough heat conducting means and / or the first connector heat conducting means and / or the second connector heat conducting means, preferably in each case, is and / or are formed by a heat conducting mat and / or by a, preferably curable and / or cured, heat conducting paste.

[0020] Embodiments of the invention are described below with reference to the accompanying figures.

[0021] They show:

[0022] Figure 1 shows a section of a battery cell in a side sectional view, wherein an external contact element of the battery cell is connected in a heat-conducting manner to a cell housing of the battery cell via breakthrough heat conduction means;

[0023] Figure 2 shows the battery cell in a side sectional view according to Figure 1, wherein a cell connector of the battery cell is additionally connected to a cell housing of the battery cell in a heat-conducting manner via connector heat-conducting means;

[0024] Figure 3 shows a perspective view of the battery cell according to Figure 2, and

[0025] Figure 4 shows a perspective view of one half of the cell connector.

[0026] Figure 1 shows a battery cell 1 for a traction battery of a battery-electric vehicle (not shown). The battery cell 1 has a cell housing 3 with a cover 5, which rests against the housing cover walls of the cell housing 3. The cell housing 3 defines a housing interior to the outside. In addition, the battery cell 1 has a cell core 7, which is formed at least partially by electrodes (not shown) of the battery cell 1. The cell core 7 is arranged in the housing interior.

[0027] The battery cell 1 also has a cell terminal. The cell terminal has an external contact element 11, which, here merely by way of example, has a plate-shaped geometry. The external contact element 11 is electrically, mechanically, and thermally connected to the cell core 7 via a connecting element 13. The connecting element 13 is formed, here merely by way of example, by a connecting element. A trough-shaped insulating element 15, here merely by way of example, is arranged between the external contact element 11 and the cover 5. The insulating element 15 is designed and / or suitable such that no electrical current flows between the external contact element 11 and the cover 5. A first opening 21 and a second opening 23 are assigned to the insulating element 15, each of which is completely delimited on the outside by the insulating element 15.

[0028] Generally speaking, a heat-conducting agent is arranged between the cell terminal, specifically the external contact element 11, and the cell housing 3, specifically the cover 5. The external contact element 11 is connected to the cover 5 via the heat-conducting agent in a heat-conducting and electrically insulating manner. Thus, heat is transferred from the external contact element 11 directly to the cover 5 via the heat-conducting agent.

[0029] In the embodiment of the battery cell 1 shown in Figures 1 and 2, the heat conduction means is formed partly by a first breakthrough heat conduction means 31 and partly by a second breakthrough heat conduction means 33. The first breakthrough heat conduction means 31 is arranged in the first opening 21 and has direct contact with both the external contact element 11 and the cover 5. The second breakthrough heat conduction means 33 is arranged in the second opening 23 and has direct contact with both the external contact element 11 and the cover 5.

[0030] As shown in Figure 2, the battery cell 1 additionally has a substantially C-shaped cell connector 41. The cell connector 41 has a base section 42 as well as a first leg 43 and a second leg 45. The first leg 43 and the second leg 45 each protrude at right angles from the base section 42 in the direction of the cover 5. The cell connector 41 rests with the base section 42 flat on the external contact element 11 and is, here merely by way of example, directly electrically connected to the cell terminal, specifically the external contact element 11. Furthermore, the cell connector 41 is, here merely by way of example, directly electrically connected to the connecting bolt 13.

[0031] The heat conduction means is formed partly by a first connector heat conduction means 47 and partly by a second connector heat conduction means 49. The first connector heat conduction means 47 is arranged between the cell connector 41, specifically the first leg 43, more specifically a front surface of the first leg 43, and the cover 5. The first leg 43, specifically the front surface of the first leg 43, is directly connected to the first connector heat conduction means 47 in a heat-conducting and electrically insulating manner, and the first connector heat conduction means 47 is directly connected to the cover 5 in a heat-conducting and electrically insulating manner. The second connector heat conduction means 49 is arranged between the cell connector 41, specifically the second leg 45, more specifically a front surface of the second leg 45, and the cover 5.The second leg 45, specifically the front surface of the second leg 45, is directly connected to the second connector heat conducting means 49 in a heat-conducting and electrically insulating manner, and the second connector heat conducting means 49 is directly connected to the cover 5 in a heat-conducting and electrically insulating manner.

[0032] As shown in particular in Figure 2, a first collar 51 of the first leg 43 adjoins the front surface of the first leg 43 in the direction of the cover 5, as can be seen in particular in Figure 4. An inner side of the first collar 51 of the first leg 43, together with the front surface of the first leg 43, delimits a first receiving pocket to the outside, in which the first connector heat-conducting means 47 is at least partially arranged. A second collar 53 of the second leg 45 adjoins the front surface of the second leg 45 in the direction of the cover 5. An inner side of the second collar 53 of the second leg 45, together with the front surface of the second leg 45, delimits a second receiving pocket to the outside, in which the second connector heat-conducting means 49 is at least partially arranged.

[0033] Figure 3 also shows a section of the battery cell 1, specifically in a perspective view. Figure 4 shows, among other things, the cell connector 41, the insulating element 15, the cover 5, as well as the first connector heat-conducting means 47 and the second connector heat-conducting means 49.

[0034] It is hereby expressly pointed out that in this or another embodiment of the battery cell 1, the external contact element 11 is thermally conductively connected to the cover 5, for example, only via one or both of the breakthrough heat conducting means 31 and 33 or, preferably with the interposition of the cell connector 41, only via one or both of the connector heat conducting means 47 and 49. Furthermore, it is also conceivable that in this or another embodiment of the battery cell 1, the external contact element 11 is thermally conductively connected to the cover 5, for example, only via one of the breakthrough heat conducting means 31 or 33 and only via one of the connector heat conducting means 47 or 49. In the battery cell 1, the first breakthrough heat conduction means 31 and the second breakthrough heat conduction means 33 and the first connector heat conduction means 47 and the second connector heat conduction means 49 are each formed by a heat conduction mat.In this or another embodiment of the battery cell 1, however, the first breakthrough thermal conduction means 31 and / or the second breakthrough thermal conduction means 33 and / or the first connector thermal conduction means 47 and / or the second connector thermal conduction means 49 can preferably each be formed by a thermally conductive mat and / or by a preferably curable and / or cured thermally conductive paste and / or by a preferably curable and / or cured thermally conductive adhesive.

[0035] List of reference symbols

[0036] Battery cell

[0037] Cell housing

[0038] Lid

[0039] cell nucleus

[0040] External contact element

[0041] connecting element

[0042] Insulating element first opening second opening first opening heat transfer medium second opening heat transfer medium

[0043] Cell connectors

[0044] Base section first leg second leg first connector thermal interface second connector thermal interface first collar second collar

Claims

Patent claims 1. Battery cell with: a cell housing (3), and a cell terminal, preferably an external contact element (11), characterized in that at least one heat conducting means is arranged between the cell terminal, preferably the external contact element (11), and the cell housing (3), and that preferably the external contact element (11) is connected to the cell housing (3) in a heat-conducting and preferably electrically insulating manner via the heat conducting means.

2. Battery cell according to claim 1, characterized in that the battery cell (1) has an insulating element (15), and that the insulating element (15), preferably for insulation against electrical current flow, is arranged between the cell housing (3) and the external contact element (11), and that a first opening (21) and / or a second opening (23) is assigned to the insulating element (15).

3. Battery cell according to claim 2, characterized in that the heat conducting means is formed at least partially by a first breakthrough heat conducting material (31) and / or by a second breakthrough heat conducting means (33), wherein it is provided that the first breakthrough heat conducting material (31) is arranged in the first opening (21), and / or wherein it is provided that the second breakthrough heat conducting material (33) is arranged in the second opening (23).

4. Battery cell according to claim 3, characterized in that the outer contact element (11) is preferably directly in contact and / or, preferably directly, thermally conductive and / or, preferably directly, electrically insulating with the first breakthrough heat conducting means (31) and / or the second breakthrough heat conducting means (33), and / or that the cell housing (3), preferably a cover (5) of the cell housing (3), is preferably directly in contact and / or, preferably directly, thermally conductive and / or, preferably directly, electrically insulating with the first breakthrough heat conducting means (31) and / or the second breakthrough heat conducting means (33).

5. Battery cell according to one of the preceding claims, characterized in that the battery cell (1) has a cell connector (41), wherein it is provided that the cell connector (41) is preferably directly electrically connected to the cell terminal, preferably the external contact element (11), and / or wherein it is provided that the cell connector (41) is preferably directly electrically connected to a connecting element (13) of the battery cell (1).

6. Battery cell according to claim 5, characterized in that the heat conducting means is formed at least partially by a first connector heat conducting means (47) and / or by a second connector heat conducting means (49), wherein it is provided that the first connector heat conducting means (47) and / or the second connector heat conducting means (49) is arranged between the cell connector (41) and the cell housing (3), preferably a cover (5) of the cell housing (3), wherein it is preferably provided that the cell connector (41) is connected to the cell housing (3), preferably a cover (5) of the cell housing (3), via the first connector heat conducting means (47) and / or via the second connector heat conducting means (49) in a heat-transferring and preferably electrically insulating manner.

7. Battery cell according to claim 5 or 6, characterized in that the cell connector (41) has a base section (42) and a first leg (43) and / or a second leg (45), wherein it is preferably provided that the base section (42) lies flat against the external contact element (11), and / or wherein it is preferably provided that the first leg (43) and / or the second leg (45) are detachable from the base section (42), preferably at right angles to a longitudinal axis of the connecting element (13) of the battery cell (1), in the direction of the cell housing (3), preferably a cover (5) of the cell housing (3).

8. Battery cell according to claim 7, characterized in that the first leg (43) has a front surface which faces the cell housing (3), preferably a cover (5) of the cell housing (3), and in that the first connector heat conducting means (47) is arranged between the front surface of the first leg (43) and the cell housing (3), preferably a cover (5) of the cell housing (3), and / or in that the second leg (45) has a front surface which faces the cell housing (3), preferably a cover (5) of the cell housing (3), and in that the second connector heat conducting means (49) is arranged between the front surface of the second leg (45) and the cell housing (3), preferably a cover (5) of the cell housing (3).

9. Battery cell according to claim 8, characterized in that on the front surface of the first leg (43) in the direction of the cell housing (3), preferably a cover (5) of the cell housing (3), a first collar (51) of the first leg (43) adjoins it, wherein it is provided that an inner side of the first collar (51) of the first leg (43), together with the front surface of the first leg (43), delimits a first receiving pocket to the outside, in which the first connector heat-conducting means (47) is at least partially arranged, and / or that a second collar (53) of the second leg (45) adjoins the front surface of the second leg (45) in the direction of the cell housing (3), preferably a cover (5) of the cell housing (3), wherein it is provided that an inner side of the second collar (53) of the second leg (45), together with the front surface of the second leg (45), delimits a second receiving pocket to the outside, in which the second connector heat-conducting means (49) is at least partially arranged.

10. Battery cell according to one of the preceding claims, characterized in that the heat conducting means is formed by a heat conducting mat and / or by a, preferably curable and / or cured, heat conducting paste, and / or the first breakthrough heat conducting means (31) and / or the second breakthrough heat conducting means (33) and / or the first connector heat conducting means (47) and / or the second connector heat conducting means (49), preferably in each case, is and / or are formed by a heat conducting mat and / or by a, preferably curable and / or cured, heat conducting paste.

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