REPRODUCED COMPONENT OF A TRACTION BATTERY PACK

Abstract

A traction battery pack assembly comprises a frame; one or more busbars secured to the frame; a printed circuit board (PCB); and an overmolded cover that secures the PCB to the frame. One method for securing a PCB of a traction battery pack involves positioning a PCB adjacent to a frame. The frame is configured to hold a plurality of busbars of a traction battery pack. The method further involves overmolding the PCB with a cover to secure the PCB relative to the frame.

Description

AREA OF TECHNOLOGY

[0001] The present disclosure relates generally to securing a component within a traction battery pack and in particular to securing the component using an overmolded cover. GENERAL STATE OF THE ART

[0002] Electrified vehicles differ from conventional motor vehicles in that they can be selectively powered by one or more electric motors, which are supplied with power by a traction battery pack. These electric motors can power the electrified vehicles instead of, or in combination with, an internal combustion engine. The traction battery pack is discharged when the one or more electric motors and other electrical consumers of the electrified vehicle are being powered. BRIEF OVERVIEW

[0003] In some aspects, the techniques described in this document relate to a traction battery pack assembly comprising: a frame; one or more busbars secured to the frame; a printed circuit board; and an overmolded cover securing the printed circuit board to the frame.

[0004] In some aspects, the techniques described in this document relate to a traction battery pack assembly, wherein the overmolded cover and the printed circuit board are arranged in a cavity of the frame.

[0005] In some aspects, the techniques described in this document relate to a traction battery pack assembly which further includes a cell stack with a multitude of connections, each extending through a corresponding slot in the frame.

[0006] In some aspects, the techniques described in this document relate to a traction battery pack assembly, in which the printed circuit board and the overmolded cover are sandwiched between the cell stack and the frame.

[0007] In some aspects, the techniques described in this document relate to a traction battery pack assembly, the frame of which consists of a polymer-based material.

[0008] In some aspects, the techniques described in this document relate to a traction battery pack assembly, wherein the busbars are secured to the frame by a variety of hot stampings.

[0009] In some aspects, the techniques described in this document relate to a traction battery pack assembly which further includes at least one sensing conductor track of the printed circuit board, wherein the one or more busbars are electrically coupled to the at least one sensing conductor track.

[0010] In some aspects, the techniques described in this document relate to a traction battery pack assembly, wherein the one or more busbars include at least one tongue extending through a slot in the frame to contact the at least one sensing conductor track.

[0011] In some aspects, the techniques described in this document relate to a traction battery pack assembly, wherein the one or more busbars are located on a first side of the frame and the overmolded cover is located on an opposite, second side of the frame.

[0012] In some aspects, the techniques described in this document relate to a traction battery pack assembly which further includes an electrical connector located on the first side of the frame and extending through the frame to be operationally connected to the circuit board.

[0013] In some aspects, the techniques described in this document relate to a traction battery assembly, where the overmolded cover is an overmolded low-pressure cover.

[0014] In some aspects, the techniques described in this document relate to a traction battery pack assembly, where the circuit board is a printed circuit board.

[0015] In some aspects, the techniques described herein relate to a traction battery assembly which further includes one or more wires secured to the frame by the overmolded cover.

[0016] In some aspects, the techniques described in this document relate to a traction battery pack assembly comprising: a frame; one or more busbars secured to the frame; one or more wires; and an overmolded cover securing the one or more wires to the frame.

[0017] In some aspects, the techniques described in this document relate to a method for securing a printed circuit board of a traction battery pack, which includes: positioning a printed circuit board adjacent to a frame, the frame being configured to hold a plurality of busbars of a traction battery pack; and overmolding the printed circuit board with a cover to secure the printed circuit board relative to the frame.

[0018] In some aspects, the techniques described in this document relate to a method for securing a printed circuit board of a traction battery pack, where the overmolding is a low-pressure overmolding process.

[0019] In some aspects, the techniques described in this document relate to a method for securing a printed circuit board of a traction battery pack, which further involves injecting material over the printed circuit board during overmolding at a pressure of 50 to 200 pounds per square inch.

[0020] In some aspects, the techniques described in this document relate to a method for securing a printed circuit board of a traction battery pack, which further involves injecting material over the printed circuit board during overmolding while the printed circuit board is held in a cavity provided by the frame.

[0021] In some aspects, the techniques described in this document relate to a method for securing a printed circuit board of a traction battery pack, which further includes a multitude of busbars secured to the frame and extending through the frame to be connected to the printed circuit board.

[0022] In some aspects, the techniques described in this document relate to a method for securing a printed circuit board of a traction battery pack, wherein the plurality of busbars is secured on a first side of the frame and the printed circuit board is overmolded on an opposite, second side of the frame.

[0023] The embodiments, examples, and alternatives described in the preceding paragraphs, the claims, or the following description and drawings, which may include any of their various aspects or individual features, can be considered independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, provided such features are not incompatible. BRIEF DESCRIPTION OF THE FIGURES

[0024] The various features and advantages of the disclosed examples will be apparent to the person skilled in the art from the detailed description. The figures accompanying the detailed description can be briefly described as follows: Fig. Figure 1 illustrates a side view of an electrified vehicle. Fig. Figure 2 illustrates a divergent perspective view of a battery pack from the electrified vehicle. Fig. 1. Fig. Figure 3 illustrates a perspective view of a battery cell from the battery pack. Fig. 2. Fig. Figure 4 illustrates a frame of a crossbeam assembly from the battery pack. Fig. 3. Fig. 5 illustrates the framework Fig. 4 with a circuit board arranged in a cavity of the frame. Fig. 6 illustrates an area from Fig. 5 with the frame and removed to show how the circuit board is coupled to an electrical connector and busbar of the crossbeam assembly. Fig. Figure 7 illustrates the framework from Fig. 5 with an overmolded cover that secures the circuit board in the cavity of the frame. DETAILED DESCRIPTION

[0025] The present disclosure describes in detail exemplary assemblies of a traction battery pack with a printed circuit board secured by an overmolded cover. The printed circuit board can be arranged in a cavity provided by a frame of a crossbeam assembly.

[0026] With reference to Fig. Figure 1 includes an electrified vehicle 10 comprising a battery pack 14, an electric motor 18, and wheels 22. The battery pack 14 supplies power to an electric motor 18, which can convert electrical power into mechanical power to drive the wheels 22. The battery pack 14 is therefore a traction battery pack.

[0027] In the exemplary embodiment, the battery pack 14 is secured to an underbody 26 of the electrified vehicle 10. In other examples, the battery pack 14 could be located elsewhere on the electrified vehicle 10.

[0028] The electrified vehicle 10 is a fully electric vehicle. In other examples, the electrified vehicle 10 is a hybrid electric vehicle that selectively drives wheels using torque provided by an internal combustion engine instead of, or in addition to, an electric motor. Generally, the electrified vehicle 10 could be any type of vehicle that incorporates a traction battery pack.

[0029] Now, with reference to Fig. 2 and Fig. In the exemplary embodiment, the battery pack 14 comprises a plurality of cell stacks 30 held within an enclosure assembly 34. The enclosure assembly 34 includes an enclosure cover 38 and an enclosure shell 42. The enclosure cover 38 can be attached to the enclosure shell 42 to provide an interior space 44 that accommodates the cell stacks 30. The enclosure cover 38 can be secured to the enclosure shell 42, for example, by mechanical fasteners (not shown).

[0030] Each of the cell stacks 30 includes, among other things, a plurality of battery cells 50 (or simply “cells”) that are stacked side by side relative to one another along a respective cell stack axis. The battery cells 50 store electrical power and supply it. Although a specific number of cell stacks 30 and cells 50 is illustrated in the various figures of the present disclosure, the battery pack 14 could include any number of cell stacks 30, each containing any number of individual cells 50.

[0031] In one embodiment, the battery cells are 50 lithium-ion pouch cells. However, within the scope of protection of the present disclosure, alternatively battery cells could be used that have other geometries (cylindrical, prismatic, etc.), other chemicals (nickel-metal hydride, lead-acid, etc.), or both.

[0032] In the cell stacks 30, the individual battery cells 50 can be electrically connected to one another. The cell stacks 30 can also be connected to one another. To enable these electrical connections, each battery cell 50 includes a pair of terminals 54 extending from a casing 58. The terminals 54 of the battery cells 50 can be connected to the terminals 54 of other battery cells 50 and to other structures.

[0033] The connecting tabs 54 are typically thin strips of foil. The connecting tabs 54 can be, for example, copper foil or aluminum foil.

[0034] In this example, in addition to the battery cells 50 of the cell stacks 30, there are crossbeam assemblies 62. The battery cells 50 of each exemplary cell stack 30 are positioned between two crossbeam assemblies 62.

[0035] The crossbeam assemblies 62 each comprise a frame 66 and one or more busbars 70, which are secured to a first side 74 of the frame 66. An opposing, second side 78 of the frame 66 faces the battery cells 50. Hot stamping secures the busbars 70 to the frame 66 in this example. The frame 66 can be made of a polymer-based material. The frame 66 can be injection-molded.

[0036] The frame 66 includes a multitude of slots 82. When the crossbeam assemblies 62 are installed, the connecting tongues 54 extend through the slots 82 from the second side 78 of the frame 66 to the first side 74 of the frame 66. The connecting tongues 54 can be folded over the busbars 70 and secured to the busbars 70, for example, by welds. This electrically connects the battery cells 50 to the busbars 70.

[0037] The crossbeam assemblies 62 include additional components. With reference to Fig. 4-7 and with further reference to Fig. 2 The crossbeam assemblies 62 include in particular a printed circuit board 86, an overmolded cover 90 and optionally an electrical connector 94.

[0038] The printed circuit boards 86 are arranged within a cavity 98 within the second side 78 of the frame 66. The overmolded cover 90 secures the printed circuit board 86 within the respective cavity 98. In another example, one or more wires, such as wires within a flexible flat cable, could be secured to the frame 66 by the overmolded cover 90. The one or more wires can be secured to the frame 66 instead of, or in addition to, the printed circuit board 86.

[0039] To mount the circuit board 86, the frame 66 can be used as shown in Fig. The frame 66 is positioned as shown in Figure 4, with the cavity 98 facing vertically upwards. Next, the printed circuit board 86 is positioned adjacent to the frame 66 within the cavity 98. With the printed circuit board 86 inside the cavity 98, the electrical connector 94 can extend from the first side 74 of the frame 66 through the frame 66 and be electrically coupled to the printed circuit board 86. The electrical connector 94 is a low-voltage electrical connector in this example.

[0040] The busbars 70 can include tongues 102, each extending through a respective opening 106 in the frame 66, to electrically couple the busbars 70 to at least one sensing conductor of the circuit board 86. The frame 66 and some of the busbars 70 are in Fig.6 omitted to show the connections between the electrical connector 94 and the circuit board 86, as well as the connection between one of the busbars 70 and the circuit board 86.

[0041] When the printed circuit board 86 is positioned within the cavity 98, a polymer-based material is injected or otherwise applied into the cavity 98 to essentially encapsulate the printed circuit board 86 within the cavity 98. Upon curing, the material provides the overmolded cover 90, which secures the printed circuit board 86 within the cavity 98. The overmolded cover 90 is bonded to the frame 66 after curing.

[0042] The exemplary overmolding process is a low-pressure overmolding process in which the material that cures to provide the overmolded cover 90 is injected over the printed circuit board 86 at a pressure between 50 and 200 pounds per inch and a nominal temperature of 180 degrees Celsius. The low-pressure overmolding process does not utilize a mold that provides a core and cavity. In other examples, the frame 66 with the printed circuit board 86 could be held within a mold, and the overmolded cover 90 could be held at least partially within a mold. In such an example, the material can be introduced over the printed circuit board 86 at higher pressures.

[0043] In particular, it is stated that the overmolded cover 90 is an overmolded cover, which structurally distinguishes the overmolded cover 90 from other types of covers that are not overmolded, such as a cover that would snap onto the frame 66. A person skilled in the art is able to structurally distinguish the overmolded cover 90 from a non-overmolded cover. The fact that the overmolded cover 90 is an overmolded cover is a structural difference that distinguishes the overmolded cover 90 from covers that are not overmolded.

[0044] When the circuit board 86 with the overmolded cover 90 is held against the second side 78 of the frame 66, the crossbeam assembly 62 can be positioned against the cells 50 of one of the cell stacks 30, so that the connecting tabs 54 extend through the slots 82. The overmolded cover 90 is then sandwiched between the frame 66 and the cell stacks 30.

[0045] The circuit board 86 is operationally coupled to both the busbars 70 and the electrical connector 94. Voltage on the busbars 70, temperatures, etc., can be monitored by operationally coupling a monitoring controller to the electrical connector 94.

[0046] In another example, the busbars 70 and the electrical connector 94 could be attached to the frame 66 after the circuit board 86 has been overmolded onto the frame 66.

[0047] In this example, circuit board 86 is a printed circuit board. In other examples, circuit board 86 could be a rigid circuit board.

[0048] Features of the disclosed examples include securing a printed circuit board using an overmolded cover. This can provide reduced assembly time and part complexity, as, among other things, no separate fasteners are required. The overmolded cover can also reduce the likelihood of dirt and moisture coming into contact with the printed circuit board.

[0049] The preceding description is exemplary and not limiting. Variations and modifications of the disclosed examples may be apparent to a person skilled in the art, which do not necessarily deviate from the core of this disclosure. Therefore, the scope of protection granted by the present disclosure can only be determined by reading the following patent claims.

[0050] According to the present invention, a traction battery pack assembly is provided comprising: a frame; one or more busbars secured to the frame; one or more wires; and an overmolded cover securing the one or more wires to the frame.

Claims

[1] Traction battery pack assembly comprising the following: a frame; one or more busbars secured to the frame; a circuit board; and an overmolded cover that secures the circuit board to the frame. [2] Traction battery pack assembly according to claim 1, wherein the overmolded cover and the circuit board are arranged in a cavity of the frame. [3] Traction battery pack assembly according to claim 1, further comprising a cell stack having a plurality of terminals extending through a respective slot in the frame, and optionally wherein the printed circuit board and the overmolded cover are sandwiched between the cell stack and the frame. [4] Traction battery pack assembly according to claim 1, wherein the frame consists of a polymer-based material. [5] Traction battery pack assembly according to claim 1, wherein the busbars are secured to the frame by a plurality of hot stampings. [6] Traction battery pack assembly according to claim 1, further comprising at least one sensing conductor track of the printed circuit board, wherein the one or more busbars are electrically coupled to the at least one sensing conductor track and optionally wherein the one or more busbars include at least one tongue extending through a slot in the frame to make contact with the at least one sensing conductor track. [7] Traction battery pack assembly according to claim 1, wherein the one or more busbars are located on a first side of the frame and the overmolded cover is located on an opposite, second side of the frame and optionally further comprising an electrical connector arranged on the first side of the frame and extending through the frame to establish an operational connection with the printed circuit board. [8] Traction battery pack assembly according to claim 1, wherein the overmolded cover is an overmolded low-pressure cover. [9] Traction battery assembly according to claim 1, wherein the circuit board is a printed circuit board. [10] Traction battery pack assembly according to claim 1, further comprising one or more wires secured to the frame by the overmolded cover. [11] Method for securing a printed circuit board of a traction battery pack, comprising the following: Positioning a printed circuit board adjacent to a frame, the frame being configured to hold a plurality of busbars of a traction battery pack; and Overmolding the circuit board with a cover to secure the circuit board relative to the frame. [12] Method for securing a printed circuit board of a traction battery pack according to claim 11, wherein the overmolding is a low-pressure overmolding. [13] Method for securing a printed circuit board of a traction battery pack according to claim 11, further comprising, during overmolding, injecting material over the printed circuit board at a pressure of 50 to 200 pounds per square inch. [14] Method for securing a printed circuit board of a traction battery pack according to claim 11, further comprising, during overmolding, injecting material over the printed circuit board while the printed circuit board is held in a cavity provided by the frame. [15] Method for securing a printed circuit board of a traction battery pack according to claim 11, further comprising a plurality of busbars secured to the frame and extending through the frame to be connected to the printed circuit board, and optionally wherein the plurality of busbars is secured to a first side of the frame and the printed circuit board is overmolded on an opposite, second side of the frame.

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