Method for connecting a first battery cell and a second battery cell of a battery, battery

Abstract

A first connecting element (103), wherein the first connecting element (103) has a contact surface (107) for a welded connection to a cell terminal (105) of a first battery cell (101) of a battery (100), in particular a high-voltage battery, wherein the first connecting element (103) has at least one contact point (110) for a welded connection to a second connecting element (104) for a welded connection to a cell terminal (106) of a second battery cell (102) of the battery (100). Battery (100) and method for connecting to the first battery cell (101) and the second battery cell (102) of the battery (100).

Description

[0001] The invention relates to a method for connecting a first battery cell and a second battery cell of a battery, and to a battery.

[0002] US 2015 / 0 072 208 A1 discloses a connecting element welded to cell terminals of two battery cells. JP 2011-40 389 A, DE 10 2019 200 004 A1, and DE 10 2014 019 505 A1 disclose connecting elements.

[0003] DE 10 2022 106 554 B3 discloses a battery cell having a housing. Furthermore, electrode stack assemblies and at least one connecting element are provided. The electrode stack assemblies are arranged in the housing. The connecting element is configured to enable electrical contacting of the electrode assemblies from the outside of the housing. The connecting element has at least one connecting portion that is electrically conductive and resiliently configured to enable elastic deformation toward the electrode stack assembly when a force is applied to the connecting portion. The connecting portion has a contact surface provided for conductive connection by a soldered or welded connection.

[0004] CN 1 12 467 271 A concerns battery production and manufacture and a battery terminal cover. A contact surface has a welded surface. This prevents the phenomenon of arc discharge.

[0005] A battery has two connecting elements, each having a contact surface for a welded connection to a cell terminal of a battery cell of a battery associated with this contact surface, wherein the first connecting element has at least one contact point for a welded connection to the second connecting element for a welded connection to the associated cell terminal of the second battery cell of the battery, wherein the contact surface of the first connecting element extends between two curved ends of the first connecting element.

[0006] The second connecting element has a contact surface for the welded connection to the cell terminal of the second battery cell of the battery.

[0007] The second connecting element has at least one contact point for a welded connection with the at least one contact point of the first connecting element.

[0008] The contact surface of the first connecting element is welded to the cell terminal of the first battery cell.

[0009] The contact surface of the second connecting element is welded to the cell terminal of the second battery cell.

[0010] At least one contact point of the first connecting element and at least one contact point of the second connecting element are welded together.

[0011] The contact surface for the welded connection to the cell terminal of the second battery cell extends between two curved ends of the second connecting element.

[0012] The first connecting element and the second connecting element each have one of the contact points for the welded connection between the first connecting element and the second connecting element at each end.

[0013] The contact points are welded together at each end.

[0014] The battery has a voltage tap so that a voltage can be measured between the two battery cells of a double cell thus formed.

[0015] Each of the two connecting elements has a bent tab at only one end between the contact points. At least one of the tabs for measuring the voltage between the battery cells is welded to the voltage tap of a measuring lead.

[0016] The battery cells form a double cell.

[0017] The contact surface for the welded connection to the cell terminal of the second battery cell extends between two curved ends of the second connecting element. This allows tolerances to be compensated.

[0018] It is therefore provided that the first connecting element has the tab for the welded connection to the voltage tap, with the battery having the voltage tap, and with the voltage tap being welded to the tab. This allows a voltage to be measured between the battery cells of the dual cell.

[0019] A method for connecting a first battery cell and a second battery cell of a battery, in particular a high-voltage battery, provides that the first connecting element and the second connecting element are provided, wherein the second connecting element has a contact surface for the welded connection to the cell terminal of the second battery cell of the battery, wherein the second connecting element has at least one contact point for a welded connection with at least one contact point of the first connecting element, wherein the contact surface of the first connecting element is welded to the cell terminal of the first battery cell, wherein the contact surface of the second connecting element is welded to the cell terminal of the second battery cell, and wherein at least one contact point of the first connecting element and at least one contact point of the second connecting element are welded to one another.This prevents excessive temperatures from entering the battery cells during welding.

[0020] In the method, it can be provided that the contact surface for the welded connection to the cell terminal of the second battery cell extends between two, in particular curved, ends of the second connecting element, and the first connecting element and the second connecting element each have a contact point for the welded connection between the first connecting element and the second connecting element, wherein the contact points are welded to one another at each end.

[0021] In the method, it can be provided that the first connecting element has the tab for the welded connection to the voltage tap, wherein the battery has the voltage tap, and wherein the voltage tap is welded to the tab.

[0022] Further advantageous embodiments can be found in the following description and the drawing. The drawing shows: Fig. 1 a schematic representation of a connection of two battery cells to a double cell, Fig. 2 a schematic representation of a voltage tap between the battery cells of the double cell, Fig. 3 a flowchart with steps of a method for connecting the battery cells.

[0023] In Fig. Figure 1 schematically shows a battery 100 with a first battery cell 101 and a second battery cell 102. The battery 100 is, for example, a high-voltage battery, particularly of a vehicle.

[0024] In Fig. 1 schematically shows a connection of the first battery cell 101 and the second battery cell 102 to form a double cell.

[0025] In the example, the connection comprises a first connecting element 103 and a second connecting element 104. The first battery cell 101 has a first cell terminal 105. The second battery cell 102 has a second cell terminal 106.

[0026] The first connecting element 103 is welded to the first cell terminal 105 at a first contact surface 107.

[0027] The second connecting element 104 is welded to the second cell terminal 106 at a second contact surface 108.

[0028] The first contact surface 107 extends between two ends of the first connecting element 103. The ends of the first connecting element 103 each have a curved shape. A tab 109 is arranged at one of the ends of the first connecting element 103. It is provided that a tab is arranged at both ends of the first connecting element 103.

[0029] The second contact surface 108 extends between two ends of the second connecting element 104. The ends of the second connecting element 104 each have a curved shape. A tab 110 is arranged at one of the ends of the second connecting element 104. It is provided that a tab is arranged at both ends of the second connecting element 104.

[0030] At each end, a contact point 111 is arranged for a welded connection between the first connecting element 101 and the second connecting element 102. The first connecting element 101 and the second connecting element 102 are welded together at the contact points 111.

[0031] In Fig. 2 shows a schematic representation of a voltage tap 112 between the first battery cell 101 and the second battery cell 102.

[0032] In the example, the voltage tap 112 is welded to the tab 109 of the first connecting element 103.

[0033] In Fig. 3 is a flowchart showing steps of a method for connecting the first battery cell 101 and the second battery cell 102.

[0034] The method includes a step 301.

[0035] In step 301, the first connecting element 103 and the second connecting element 104 are provided.

[0036] The method includes a step 302.

[0037] In step 302, the contact surface 107 of the first connecting element 103 is welded to the cell terminal 105 of the first battery cell 101.

[0038] The method includes a step 303.

[0039] In step 303, the contact surface 108 of the second connecting element 104 is welded to the cell terminal 106 of the second battery cell 102.

[0040] The method includes a step 304.

[0041] In step 304, at least one contact point 111 of the first connecting element 103 and at least one contact point 111 of the second connecting element 104 are welded together.

[0042] The contact points 111 are welded together at each end.

[0043] The method optionally includes a step 305.

[0044] In step 305, the voltage tap 112 is welded to the tab 109.

[0045] In the battery 100, several battery cells are installed in pairs in a star configuration. The electrical connection between these battery cells is established via respective connecting elements, e.g., via busbars. One connecting element is welded to each cell terminal. The connecting elements are then welded together. The connecting elements that contact a double cell are characterized by their geometry, particularly the curved shape of the ends, that allows them to have a tolerance-compensating function. This means that the connecting elements that connect the double cell represent a tolerance range.

[0046] In the example, the contact surfaces and the cell terminals or the contact points 111 are welded by laser welding.

[0047] A measuring line is provided which includes the voltage tap 112.

[0048] It is provided that a voltage tap 112 is arranged between several or between each double cell of the battery 100. The method can provide that the voltage measurement takes place between the several or between each of the double cells.

Claims

[1] Battery (100) comprising two connecting elements (103, 104), each having a contact surface (107, 108) for a welded connection to a cell terminal (105, 106) of a battery cell (101, 102) of a battery (100) associated with said contact surface (107, 108), wherein the first connecting element (103) has at least one contact point (111) for a welded connection to the second connecting element (104) for a welded connection to the associated cell terminal (106) of the second battery cell (102) of the battery (100), wherein the contact surface (107) of the first connecting element (103) extends between two curved ends of the first connecting element (103), wherein the second connecting element (104) has a contact surface (108) for the welded connection to the cell terminal (106) of the second battery cell (102) of the battery (100), wherein the second connecting element (104) has at least one contact point (111) for a welded connection with the at least one contact point (111) of the first connecting element (103), wherein the contact surface (107) of the first connecting element (103) is welded to the cell terminal (105) of the first battery cell (101), wherein the contact surface (108) of the second connecting element (104) is welded to the cell terminal (106) of the second battery cell (102), and wherein at least one contact point (111) of the first connecting element (103) and at least one contact point (111) of the second connecting element (104) are welded to one another, wherein the contact surface (108) for the welded connection to the cell terminal (106) of the second battery cell (102) extends between two curved ends of the second connecting element (104), wherein the first connecting element (103) and the second connecting element (104) each have one of the contact points (111) for the welded connection between the first connecting element (103) and the second connecting element (104) at each end, wherein the contact points (111) are welded to one another at each end, wherein the battery (100) has a voltage tap (112) so that a voltage between the two battery cells (101, 102) of a double cell thus formed can be measured, wherein each of the two connecting elements (103, 104) has a bent tab (109 or 110) at only one of the ends between the contact points (111), wherein at least one of the tabs (109) for measuring the voltage between the battery cells (101, 102) is welded to the voltage tap of a measuring line. [2] Method for connecting a first battery cell (101) and a second battery cell (102) of a battery (100), in particular a high-voltage battery, characterized bythat the two connecting elements (103, 104) are provided according to claim 1 (301), wherein the second connecting element (104) has a contact surface (108) for the welded connection to the cell terminal (106) of the second battery cell (102) of the battery (100), wherein the second connecting element (104) has at least one contact point (111) for a welded connection with at least one contact point (111) of the first connecting element (103), wherein the contact surface (107) of the first connecting element (103) is welded to the cell terminal (105) of the first battery cell (101) (302), wherein the contact surface (108) of the second connecting element (104) is welded to the cell terminal (106) of the second battery cell (102) (303), and wherein at least one contact point (111) of the first connecting element (103) and at least one contact point (111) of the second connecting element (104) are welded together (304). [3] Method according to claim 2, characterized by that the contact surface (108) for the welded connection to the cell terminal (106) of the second battery cell (102) extends between two curved ends of the second connecting element (104), and the first connecting element (103) and the second connecting element (104) each have a contact point (111) for the welded connection between the first connecting element (103) and the second connecting element (104), wherein the contact points (111) are welded to one another at each end (304). [4] Method according to one of claims 2 or 3, characterized by that the first connecting element (103) has the tab (109) for the welded connection to the voltage tap (112), wherein the battery (100) has the voltage tap (112), and wherein the voltage tap (112) is welded to the tab (109) (305).

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