Systems and methods for battery modules having terminal block assemblies with drainage channels

Abstract

The present disclosure generally relates to the field of batteries and battery modules, and more specifically to systems and methods for producing terminal assemblies for lithium-ion battery modules. The battery module of the present disclosure includes a terminal area assembly that is fixed to a polymer housing of the battery module. The terminal area assembly includes a terminal post having a column portion and a base portion extending outward from the central axis of the column portion. The terminal area assembly also includes a bus bar that is coupled to the base portion of the terminal post without welding, wherein the bus bar includes a groove disposed near the terminal post. The terminal area assembly also includes a polymer portion that at least overlies the groove of the molded bus bar to form a drainage channel near the terminal post.

Description

[0001] This application is a divisional application of an invention patent application with an application date of July 19, 2017, an international application number of PCT / US2017 / 042913, a national application number of 201780055375.X, and an invention name of “Systems and methods for battery modules having wiring area components with drainage channels”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application is related to U.S. patent application 15 / 158,321, entitled “SYSTEM AND METHOD OF OVERMOLDED TERMINAL POSTS OF A BATTERY MODULE,” filed on May 18, 2016, and U.S. patent application 15 / 226,646, entitled “SYSTEMS AND METHODS FOR BONDING METAL PARTS TO THE POLYMER PACKAGING OF A BATTERY MODULE,” filed on August 2, 2016, the entirety of which is incorporated herein by reference for all purposes. Background Art

[0004] The present disclosure relates generally to the field of batteries and battery modules. More specifically, the present disclosure relates to systems and methods for producing terminal assemblies for lithium-ion battery modules.

[0005] This section is intended to introduce the reader to various aspects of the art that may be related to the various aspects of the present disclosure described below. It is believed that this discussion helps to provide background information to the reader in order to better understand the various aspects of the present disclosure. Therefore, it should be understood that these descriptions should be read from this perspective and should not be regarded as an admission of the prior art.

[0006] A vehicle that uses one or more battery systems to provide all or part of the motive power for the vehicle may be referred to as an xEV, wherein the term "xEV" is defined herein as including all of the following vehicles that use electricity as all or part of the motive power of the vehicle, or any variation or combination thereof. For example, xEV includes an electric vehicle (EV) that uses electricity as all motive power. It will be appreciated by those skilled in the art that a hybrid electric vehicle (HEV) (also considered to be an xEV) combines an internal combustion engine propulsion system and a battery-powered electric propulsion system (e.g., a 48 volt (V) or 130 volt system). The term HEV may include any variation of a hybrid electric vehicle. For example, a full hybrid system (FHEV) may use one or more electric motors to provide motive power and other electricity to the vehicle using only an internal combustion engine or using both an electric motor and an internal combustion engine. In contrast, a mild hybrid system (MHEV) deactivates the internal combustion engine when the vehicle is idling, uses a battery system to continue to power an air conditioning unit, a radio, or other electrical devices, and restarts the engine when propulsion is required. A mild hybrid system may also apply a certain degree of power assistance during, for example, acceleration to supplement the internal combustion engine. Mild hybrid systems are generally 96V to 130V, and brake energy is recovered through a belt-type or crank-type integrated starter generator. In addition, micro-hybrid electric vehicles (mHEVs) also use a "start-stop" system similar to the mild hybrid system, but the micro-hybrid system of the mHEV may or may not provide power assistance to the internal combustion engine and operates at a voltage below 60V. For the purpose of the current discussion, it should be noted that mHEVs generally do not technically use electricity directly provided to the crankshaft or transmission as the motive force for any part of the vehicle, but mHEVs can still be considered an xEV because when the vehicle is idling with the internal combustion engine disabled, it does use electricity to supplement the vehicle's power needs and recovers braking energy through an integrated starter generator. In addition, a plug-in electric vehicle (PEV) is any vehicle that can be charged from an external power source (e.g., a wall socket), and the energy stored in the rechargeable battery pack drives or helps drive the wheels. PEV is a subcategory of EV and includes pure electric vehicles or battery electric vehicles (BEV), plug-in hybrid electric vehicles (PHEV), and electric vehicle conversions of hybrid electric vehicles and conventional internal combustion engine vehicles.

[0007] Such xEVs may provide a number of advantages over more traditional gas-powered vehicles that use only an internal combustion engine and a conventional electrical system (which is typically a 12V system powered by a lead-acid battery). For example, xEVs may produce fewer undesirable emissions and may exhibit greater fuel efficiency than conventional internal combustion engine vehicles, and in some cases, such xEVs may not use gasoline at all, as some types of EVs or PEVs do.

[0008] As technology continues to evolve, there is a need to provide improved power sources for such vehicles, particularly battery modules. For example, in a conventional configuration, a battery module may include a complex electrical coupling structure between the electrochemical cells and the terminals of the battery module. In addition, because the terminals extend through a portion of the battery module's enclosure, it is desirable to have a terminal design that prevents water or debris from entering the battery module's enclosure. Summary of the invention

[0009] The following describes an overview of certain embodiments disclosed herein. It should be understood that these aspects are presented only to provide the reader with a brief overview of these embodiments and that these aspects are not intended to limit the scope of the present disclosure. In fact, the present disclosure may encompass various aspects that may not be described below.

[0010] The present disclosure relates to a battery module including a terminal block assembly that is fixed to a polymer housing of the battery module. The terminal block assembly includes a terminal post having a post portion and a base portion extending outwardly from a central axis of the post portion. The terminal block assembly also includes a bus bar that is coupled to the base portion of the terminal post without welding, wherein the bus bar includes a trough disposed near the terminal post. The terminal block assembly also includes a polymer portion that at least overlies the trough of the molded bus bar to form a drainage channel near the terminal post.

[0011] The present disclosure also relates to a method for producing a battery module. The method includes setting a post portion of a terminal so that it passes through an opening in a busbar, wherein the busbar includes a groove disposed near the opening in the busbar, and bending one or more flaps of the busbar around a base portion of the terminal so as to fix the terminal to the busbar without welding. The method includes overmolding a polymer around a portion of the busbar and the terminal to obtain a terminal area assembly, wherein the portion includes a groove of the busbar to form a drainage channel for the terminal area assembly. The method also includes setting the terminal area assembly in a socket of a polymer housing of the battery module. The method also includes electrically coupling the terminal area assembly to a power assembly of the battery module, and sealing the terminal area assembly in a socket of a polymer housing of the battery module.

[0012] The present disclosure also relates to a battery module having an electrical component that includes a plurality of lithium-ion battery cells. The battery module has a first terminal block assembly that includes a first terminal post having a column portion and a base portion extending outwardly from a central axis of the column portion. The first terminal block assembly includes a first bus bar that is coupled to a base portion of the first terminal post without welding to form a first electrical component, wherein the first bus bar includes a groove disposed near the first terminal post, and wherein the first electrical component is electrically coupled to the electrical component of the battery module. The first terminal block assembly also includes a first polymer portion that overmolds at least a portion of the first electrical component, wherein the portion includes a groove of the first bus bar and forms a first drainage channel near the first terminal post. The battery module also includes a polymer housing that includes a first socket that is welded to the first polymer portion of the first terminal block assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Various aspects of the present disclosure may be better understood upon reading the following detailed description and referring to the accompanying drawings, in which:

[0014] Figure 1 is a perspective view of a vehicle having a battery system configured to provide power to various components of the vehicle according to an embodiment of the present disclosure;

[0015] Figure 2 According to the embodiment of the present disclosure Figure 1 A cross-sectional schematic diagram of an embodiment of a vehicle and a battery system;

[0016] Figure 3 According to the embodiments of the present disclosure Figure 1 An exploded perspective view of an embodiment of a battery module used in a battery system;

[0017] Figure 4 is a perspective view of an embodiment of a terminal block assembly, according to an embodiment of the present disclosure, the terminal block assembly is designed to be sealed to Figure 3 In a socket of a housing of a battery module;

[0018] Figure 5 According to the embodiment of the present disclosure Figure 4 An exploded perspective view of the wiring area assembly shown;

[0019] Figure 6 is a bottom perspective view of a bus bar and a terminal post of a terminal block assembly before the terminal post is secured to the bus bar according to an embodiment of the present disclosure;

[0020] Figure 7is a bottom perspective view of an electrical assembly of a terminal block assembly, wherein the tabs of a bus bar have been bent to secure a base portion of a terminal post within a pocket of the bus bar in accordance with an embodiment of the present disclosure;

[0021] Figure 8 According to the embodiments of the present disclosure, Figure 4 A perspective view of an embodiment of a socket of a housing of a wiring area assembly;

[0022] Fig. 9 According to the embodiment of the present disclosure, the Figure 8 In the socket Figure 4 A perspective view of an embodiment of a wiring area assembly;

[0023] Fig.10 The embodiment of the present disclosure is used to produce Figure 3 A flowchart of a process for a battery module;

[0024] Fig.11 is a perspective view of another electrical component design for a wiring area assembly according to an embodiment of the present disclosure;

[0025] Fig.12 is a perspective view of another embodiment of a wiring area component design according to an embodiment of the present disclosure; and

[0026] Fig.13 is a stereoscopic diagram of another wiring area component design according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0027] One or more specific embodiments will be described below. In order to provide a concise description of these embodiments, not all features of the actual implementation are described in this specification. It should be understood that in the development of any such actual implementation, such as in any engineering or design project, many implementation-specific decisions must be made to achieve the developer's specific goals, such as complying with system-related and business-related constraints, which may vary from implementation to implementation. Moreover, it should be understood that such development work may be complex and time-consuming, but will be a routine task of design, fabrication, and manufacturing for a person of ordinary skill who benefits from this disclosure.

[0028] The battery systems described herein can be used to provide power to various types of electric vehicles (xEVs) and other high voltage energy storage / energy consumption applications (e.g., grid power storage systems). Such battery systems may include one or more battery modules, each having a plurality of battery cells (e.g., lithium ion (Li-ion) electrochemical battery cells) that are arranged and electrically interconnected to provide a specific voltage and / or current for powering one or more components of, for example, an xEV. As another example, a battery module according to an embodiment of the present disclosure may be incorporated with or provide power to a stationary power system (e.g., a non-motor vehicle system).

[0029] According to an embodiment of the present disclosure, each electrochemical cell can be positioned in a housing of a battery module, and the terminals of the electrochemical cell (e.g., secondary terminals or cell terminals) can generally extend outward from the electrochemical cell within the housing. In order to couple the electrochemical cells together (e.g., in series or in parallel), an electrical path can be constructed between the secondary terminals of two or more electrochemical cells by coupling the secondary terminals of the electrochemical cells together, thereby forming a power assembly. In addition, two electrochemical cells in the power assembly (e.g., at either end of the battery module or at multiple ends of one or more electrochemical cell stacks) can be electrically coupled to the main terminals of the battery module (e.g., module terminals, primary terminals, terminals) via corresponding bus bars or via corresponding bus bar assemblies, wherein the main terminals are configured to be coupled to a load to power the load.

[0030] In conventional configurations, in order to ensure that the main terminals and their associated bus bars do not become detached, the main terminals and the bus bars are typically welded together. However, welding of the main terminals and the bus bars typically requires that the material of the bus bars be the same as that of the main terminals, or at least that the two materials be compatible for welding. In addition, the material of the bus bar may depend on the material of the corresponding secondary terminals (e.g., the terminals of the electrochemical battery cells) or the material of one or more intermediate components (e.g., a shunt coupled to a printed circuit board). This may increase the material cost and production complexity of the battery module. In addition, the associated geometric structures, assembly and welding techniques used in conventional configurations (such as those described above) may have an impact on the volume of the battery module, thereby reducing the energy density of the battery module.

[0031] In order to address these and other shortcomings of conventional battery module configurations, a battery module according to the present disclosure includes at least one wiring area assembly. The wiring area assembly typically has an electrical component that includes a terminal and a bus bar that can be coupled together without welding, so that the two components can be made of similar or different materials. In addition, some portions of the electrical component are overmolded by a polymer to form the wiring area assembly of the present disclosure. The wiring area assembly is designed to be received by a socket or cavity in a polymer housing of the battery module. Subsequently, the polymer portion of the wiring area assembly can be sealed (e.g., welded, adhered) to the housing to prevent electrolyte from leaking from the housing and / or to prevent moisture or fluid from leaking into the housing.

[0032] In addition, additional features are included in the design of the terminal block assembly of the present disclosure to block fluid (e.g., water) near the terminal post and redirect the fluid so that the fluid does not enter the housing. For example, as discussed in detail below, the bus bar of the present disclosure includes a groove feature (e.g., a U-shaped bend, shaped similar to a p-shaped trap) disposed near the terminal post. In certain embodiments, once the polymer portion of the terminal block assembly is secured to the housing, the groove forms a drainage channel that directs fluid that contacts the exterior of the housing near the terminal post to drain rather than remain (e.g., collect, pool) near the main terminals of the battery module. Therefore, by allowing fluid to drain from the main terminals, the terminal block assembly design of the present disclosure enables the manufacture of a battery module that is better protected from fluid entering the battery module housing and provides better protection for the main terminals (and any associated electrical connections) from corrosion caused by fluid or moisture that accumulates near the main terminals. In addition, the curved shape (e.g., U-shaped bend, S-shaped bend) of the bus bar of the present disclosure further provides a tortuous path that prevents (e.g., prevents, blocks) undesirable environmental factors (e.g., fluid, water, air, corrosion) from passing through (e.g., capillary adsorption) along the surface of the bus bar and entering the packaging of the battery module. These and other features are described in detail below with reference to the accompanying drawings.

[0033] To help illustrate, Figure 1 is a perspective view of an embodiment of a vehicle 10 that can utilize a regenerative braking system. Although the following discussion is directed to a vehicle with a regenerative braking system, the techniques described herein may be applicable to other vehicles that use batteries to capture / store electrical energy, including electric vehicles and gasoline-powered vehicles.

[0034] As described above, it can be expected that the battery system 12 is largely compatible with conventional vehicle designs. Therefore, the battery system 12 can be placed in the vehicle 10 at a location that would otherwise accommodate a conventional battery system. For example, as shown, the vehicle 10 can include a battery system 12 that is located similarly to the location of a lead-acid battery of a typical internal combustion engine vehicle (e.g., under the hood of the vehicle 10). In addition, as will be described in more detail below, the battery system 12 can be positioned to facilitate management of the temperature of the battery system 12. For example, in some embodiments, positioning the battery system 12 under the hood of the vehicle 10 can enable ventilation ducts to direct airflow through the battery system 12 and cool the battery system 12.

[0035] Figure 2 10. As shown, the battery system 12 includes an energy storage component 13 that is coupled to an ignition system 14, an alternator 15, a vehicle center console 16, and optionally to an electric motor 17. In general, the energy storage component 13 can capture / store electrical energy generated in the vehicle 10 and output the electrical energy to power electrical devices in the vehicle 10.

[0036] In other words, the battery system 12 can power components of the vehicle electrical system, which can include a radiator cooling fan, a climate control system, an electric steering system, an active suspension system, an automatic parking system, an electric oil pump, an electric supercharger / turbocharger, an electric water pump, a heated windshield / defroster, a window lift motor, a vanity light, a tire pressure monitoring system, a sunroof motor controller, a power seat, an alarm system, an infotainment system, a navigation feature, a lane departure warning system, an electric parking brake, exterior lights, or any combination thereof. Exemplarily, in the illustrated embodiment, the energy storage component 13 powers a vehicle center console 16 and an ignition system 14, which can be used to start (e.g., crank) an internal combustion engine 18.

[0037] In addition, the energy storage component 13 can capture electrical energy generated by the AC generator 15 and / or the motor 17. In some embodiments, the AC generator 15 can generate electrical energy when the internal combustion engine 18 is running. More specifically, the AC generator 15 can convert mechanical energy generated by the rotation of the internal combustion engine 18 into electrical energy. Additionally or alternatively, when the vehicle 10 includes an electric motor 17, the electric motor 17 can generate electrical energy by converting mechanical energy generated by the movement of the vehicle 10 (e.g., wheel rotation) into electrical energy. Therefore, in some embodiments, the energy storage component 13 can capture electrical energy generated by the AC generator 15 and / or the motor 17 during regenerative braking. Therefore, the AC generator 15 and / or the motor 17 are collectively referred to as a regenerative braking system herein.

[0038] To assist in capturing and supplying electrical energy, the energy storage component 13 may be electrically coupled to the vehicle's electrical system via a bus 19. For example, the bus 19 may enable the energy storage component 13 to receive electrical energy generated by the alternator 15 and / or the motor 17. Additionally, the bus 19 may enable the energy storage component 13 to output electrical energy to the ignition system 13 and / or the vehicle center console 16. Thus, when a 12 volt battery system 12 is used, the bus 19 may transmit power typically between 8-18 volts.

[0039] In addition, as shown in the figure, the energy storage component 13 may include a variety of battery modules. For example, in the illustrated embodiment, the energy storage component 13 includes a lithium-ion (e.g., first) battery module 20 and a lead-acid (e.g., second) battery module 22 according to an embodiment of the present disclosure, wherein each battery module 20, 22 includes one or more battery cells. In other embodiments, the energy storage component 13 may include any number of battery modules. In addition, although the lithium-ion battery module 20 and the lead-acid battery module 22 are illustrated as being adjacent to each other, they may be positioned in different areas throughout the vehicle. For example, the lead-acid battery module 22 may be positioned in or around the interior of the vehicle 10, while the lithium-ion battery module 20 may be positioned under the hood of the vehicle 10.

[0040] In some embodiments, the energy storage component 13 may include multiple battery modules to utilize multiple different battery chemistries. For example, when lithium-ion battery modules 20 are used, the performance of the battery system 12 may be improved because lithium-ion battery chemistries generally have higher coulombic efficiency and / or higher charge acceptance (e.g., higher maximum charge current or charge voltage) than lead-acid battery chemistries. Thus, the capture, storage, and / or distribution efficiency of the battery system 12 may be improved.

[0041] To help control the capture and storage of electrical energy, the battery system 12 may also include a control module 24. More specifically, the control module 24 may control the operation of components in the battery system 12, such as the operation of relays (e.g., switches) within the energy storage component 13, the alternator 15, and / or the motor 17. For example, the control module 24 may adjust the amount of electrical energy captured / supplied by each battery module 20 or 22 (e.g., reduce and reset the rating of the battery system 12), load balance between the battery modules 20 and 22, determine the state of charge of each battery module 20 or 22, determine the temperature of each battery module 20 or 22, control the voltage output by the alternator 15 and / or the motor 17, and the like.

[0042] Therefore, the control unit 24 may include one or more processors 26 and one or more memories 28. More specifically, the one or more processors 26 may include one or more application specific integrated circuits (ASICs), one or more field programmable gate arrays (FPGAs), one or more general purpose processors, or any combination thereof. In addition, the one or more memories 28 may include volatile memory, such as random access memory (RAM), and / or non-volatile memory, such as read-only memory (ROM), an optical drive, a hard drive, or a solid-state drive. In some embodiments, in some embodiments, the control unit 24 may include multiple parts of a vehicle control unit (VCU) and / or a separate battery control module.

[0043] Figure 3 Shown in Figure 2 1 is an exploded top perspective view of an embodiment of a battery module 20 in a vehicle 10. In the illustrated embodiment, the battery module 20 (e.g., a lithium ion [Li-ion] battery module) includes a polymer housing 30 and electrochemical cells 32 (e.g., prismatic lithium ion [Li-ion] electrochemical cells) disposed within the housing 30. In the illustrated embodiment, six prismatic Li-ion electrochemical cells 32 are disposed within the housing 30 in two cell stacks 34, each of which has three electrochemical cells 32. However, in other embodiments, the battery module 20 may include any number of electrochemical cells 32 (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, or more electrochemical cells), any type of electrochemical cells 32 (e.g., Li-ion, lithium polymer, lead acid, nickel cadmium or nickel metal hydride, prismatic and / or cylindrical electrochemical cells), and any arrangement of the electrochemical cells 32 (e.g., stacked, separated, or partitioned).

[0044] As shown, the electrochemical cell 32 can include a terminal 36 (e.g., a cell terminal, a secondary terminal) extending upward (e.g., in a direction 37) from a terminal end 39 of the electrochemical cell. Thus, the terminal 36 can extend into an opening 38 provided in an upper side 40 or top surface of the housing 30. For example, the electrochemical cell 32 can be inserted into the housing 30 through the opening 38 in the upper side 40 and positioned within the housing 30 such that the terminal 36 of the electrochemical cell 32 is disposed in the opening 38. A bus bar carrier 42 can be disposed in the opening 38 and can hold a secondary bus bar 44 (e.g., a cell-to-cell bus bar, a terminal bus bar) disposed on the bus bar carrier 42 in place, and the bus bar carrier 42 is configured to interface with the terminal 36 of the electrochemical cell 32. For example, the secondary bus bars 44 may interface with the terminals 36 to electrically couple adjacent electrochemical cells 32 together (e.g., to form a power assembly 45 of electrically interconnected electrochemical cells 32). The secondary bus bars 44 may be mounted or disposed on or near the top or bottom surface or the top or bottom surface of the bus bar carrier 42 (e.g., facing away from the electrochemical cells 32 or facing the electrochemical cells 32). However, in other embodiments, the battery module 20 may not include a bus bar carrier 42 and the secondary bus bars 44 may be disposed directly onto the terminals 36.

[0045] Depending on the embodiment, the secondary bus bars 44 may connect the electrochemical cells 32 in series, in parallel, or connect some electrochemical cells 32 in series and some electrochemical cells 32 in parallel to form a power assembly 45 of the battery module 20. In addition, some of the secondary bus bars 44 may be configured to electrically couple a group of electrochemical cells 32 that are electrically interconnected to a main terminal 46 (e.g., module terminal, terminal post) of the battery module 20, wherein the main terminal 46 is configured to be connected to a load (e.g., Figure 1 and 2 The cover 50 (which may be part of the housing 30 or may be a separate component) may be disposed over the bus bar carrier 42 to seal the opening 38 in the housing 30 of the battery module 20 and / or to protect the secondary bus bars 44, other components disposed on the bus bar carrier 42, and / or other components of the battery module 20. In addition, a panel 54 may be disposed over an adjacent side 56 of the housing 30 (e.g., a side adjacent to the area of ​​the housing 30 that holds the electrochemical cells 32) to protect other components (e.g., electrical components) secured to the adjacent side 56 of the housing 30.

[0046] As previously described, each of the main terminals 46 of the illustrated battery module 20 is a terminal block assembly 58 that is electrically coupled to the power assembly 45 to deliver the appropriate positive or negative voltage to the attached load. Although the structure of the terminal block assembly 58 is discussed in more detail below, the terminal posts 60 of the terminal block assembly 58 are electrically coupled to the power assembly 45 via bus bars (not shown) of the terminal block assembly 58. In addition, the polymer portion 62 of each terminal block assembly 58 is fixed (e.g., sealed, adhered, welded) to a corresponding socket 64 to form a waterproof polymer housing 30. These and other features of the terminal block assembly 58 and the socket 64 of the housing 30 will be described in detail below.

[0047] In view of the foregoing, Figure 4 is a perspective view of an embodiment of a wiring area assembly 58 according to an embodiment of the present disclosure. In order to better illustrate the various components, Figure 5 yes Figure 4 , which enables a clearer view of the terminal block 60, bus bar 66, and polymer portion 62. As discussed in more detail below, the terminal block assembly 58 is designed to be inserted and sealed in the receptacle 64 of the housing 30 to act as a Figure 3 The main terminals 46 (e.g., positive terminals, negative terminals) of the battery module 20.

[0048] for Figure 4 and 5 In the embodiment shown in FIG. 5 , the terminal block assembly 58 includes a metal terminal post 60 having a column portion 68 and a base portion 70. In some embodiments, the terminal post 60 may be made of copper, aluminum, nickel, stainless steel, or a combination of the above materials. In the embodiment shown, the base portion 70 is generally aligned with the column portion 68 axially along the same axis and is positioned at the end of the column portion 68. The base portion 70 has a circumference (e.g., defined by the side 72 of the base portion 70) that is generally larger than (e.g., extends beyond) the circumference of the column portion 68. In some embodiments, the base portion 70 may be integrally formed with the column portion 68 of the terminal post 60. In some embodiments, the base portion 70 and the column portion 68 may be separate components that are welded or otherwise combined together (e.g., by screwing the column portion 68 into a threaded opening in the base portion 70). The base portion 70 of the terminal post 60 shown may be described as having a super-ellipsoidal shape (e.g., a square with slightly concave sides that bend inward toward the central axis of the column portion 68). According to the present disclosure, in other embodiments, the base portion 70 may have other cross-sectional shapes (eg, triangular, square, hexagonal). Figure 4 and 5The post portion 68 of the terminal post 60 shown in FIG. 1 provides a male threaded connection, which is designed to receive a female threaded electrical connector (not shown) to couple the battery module 20 to a load. According to the present disclosure, in other embodiments, the terminal post 60 may include a different connector (e.g., a female threaded connector; a smooth post connector; a flange connector) to achieve connection with other types of electrical connectors.

[0049] The illustrated terminal block assembly 58 also includes a bus bar 66 that is physically and electrically coupled to the terminal post 60. In some embodiments, the bus bar 66 can be made of copper, aluminum, nickel, stainless steel, or a combination thereof. As described above, in some embodiments, the bus bar 66 and the terminal post 60 can be made of the same or different metals. As discussed in more detail below, the post portion 68 of the terminal post 60 extends through the opening 74 in the base 76 of the bus bar 66, while the base portion 70 of the terminal post 60 is secured to the bus bar 66 via the tabs 78 of the bus bar 66. As shown in FIG. Figure 5 As shown in FIG. 6 , the illustrated bus bar 66 also includes a slot 80 (e.g., a U-shaped bend along the width 82 of the bus bar 66) disposed adjacent to the base 76 of the bus bar 66, near the terminal 60, and extending below the plane of the base 76 of the bus bar 66. In addition, the bus bar 66 also includes a hairpin bend 84 (e.g., a U-shaped bend elongated along the width 82 of the bus bar 66) extending in a direction opposite to the slot (e.g., above the plane of the base 76 of the bus bar 66). In addition, the illustrated bus bar 66 also includes a small bend 85 (e.g., an S-shaped bend) extending along the width 82 of the bus bar 66, separating the extension 86 from the remainder of the bus bar 66.

[0050] In addition, the illustrated terminal block assembly 58 includes a polymer portion 62 that overmoldes the bus bar 66 and portions of the terminal post 60. In certain embodiments, the polymer portion 62 may be made of polypropylene, polypropylene containing fiberglass, nylon (e.g., nylon 66), or other suitable polymers. Figure 4As shown in , the polymer portion 62 overmolds a majority of the bus bar 66, which electrically isolates these overmold portions to prevent undesired electrical connection to the bus bar 66. However, the extension 86 of the bus bar 66 of the terminal block assembly 58 remains exposed to enable the bus bar 66 to be electrically coupled (e.g., directly or indirectly) to the power assembly 45 of the battery module 20, thereby providing the appropriate voltage to the terminal post 60 for coupling to a suitable load. It will be appreciated that in certain embodiments, the extension 86 of the bus bar may have additional features (e.g., a bend or bend) to enable the bus bar 66 to be electrically coupled to the power assembly 45. In addition, as shown, the polymer portion 62 may not cover the base 76 of the bus bar 66, so that the base 76 of the bus bar 66 is exposed around the opening 74 of the bus bar 66, and the post portion 68 of the terminal post 60 extends through the opening. For example, in some embodiments, rather than merely positioning the terminal stud 60 , a connector (eg, a female threaded connector) may be fully tightened onto the terminal stud 60 until it makes physical and electrical contact with the base 76 of the bus bar 66 .

[0051] The polymer portion 62 of the terminal block assembly 58 is shown as having a substantially rectangular cross-section designed to facilitate insertion of the terminal block assembly 58 into the Figure 3 30 . In addition, the polymer portion 62 includes a lip 88 extending outwardly from a side 90 of the polymer portion 62 of the terminal block assembly 58, which is designed to contact and seal (e.g., weld, adhere) to an outer portion of the socket 64 of the housing 30 to secure the terminal block assembly 58 to the housing 30. In addition, it can be appreciated that the illustrated embodiment of the terminal block assembly 58 includes tapered (e.g., chamfered) side portions 92 disposed below the lip 88. Therefore, for certain embodiments, these tapered side portions 92 can correspond to opposite (e.g., complementary) tapered side portions (not shown) of the socket 64 of the housing to further achieve a secure fit between the terminal block assembly 58 and the socket 64 of the housing 30.

[0052] In addition, if Figure 4 , the polymer portion 62 of the terminal block assembly 58 over molds the slot 80 and hairpin bend 84 of the bus bar 66. As shown, once the polymer portion 62 of the terminal block assembly 58 over molds these features, the hairpin bend 84 is disposed below the rectangular portion 94 of the polymer portion 62. It will be appreciated that in other embodiments, this rectangular portion 94 may have a greater degree of rounding (e.g., similar to the shape of the hairpin bend 84 below).

[0053] like Figure 4As shown in , once overmolded with the polymer portion 62, the grooves 80 of the bus bar 66 form drainage channels 96 of the terminal block assembly 58. The drainage channels 96 are generally disposed adjacent the base 76 of the bus bar 66, near the post portion 68 of the terminal block assembly 58, and define an elevation 98 (e.g., a maximum height) that is less than an elevation 100 (e.g., a maximum height) of the plane of the base 76 of the bus bar 66 of the terminal block assembly 58. The drainage channels 96 can also be described as being disposed adjacent an interface 97 where the polymer portion 62 meets the exposed surface of the base 76 of the bus bar 66 and encourage fluids (e.g., water) to drain from the sides 90 of the terminal block assembly 58 rather than allowing the fluids to pool at this interface 97. Figure 4 and 5 In the embodiment of the terminal block assembly 58 shown in FIG, the drainage channel 96 extends at least a small distance 102 (e.g., between about 0.1 mm and about 5 mm, between 1 mm and 2 mm) below the plane of the base 76 of the bus bar 66 to facilitate drainage of fluid from the terminal post 60. In addition, in the event that fluid (e.g., water) leaks across the polymer / terminal interface, the groove can capture the fluid or direct the fluid in a direction away from the electrochemical cell 32 and / or any underlying supporting electronic circuitry 101 (e.g., control switches, control / monitoring circuitry, power conversion circuitry) disposed near the main terminals 46 of the battery module 20 (e.g., Figure 3 In other embodiments, Figure 5 The fewer grooves 80 shown in FIG. 1 may be overmolded by the polymer portion 62 to obtain a drainage channel 96 that is a greater distance (e.g., a lower elevation) below the plane of the base 76. Additionally, in some embodiments, the polymer portion 62 may be conformally overmolded. Figure 5 The grooves 80 of the bus bar 66 shown in the figure are provided to obtain drainage channels 96 having similar size and shape (e.g., similar width, depth, and curvature) as the grooves 80 of the bus bar. In addition, as described below, although certain embodiments of the terminal block assembly 58 of the present disclosure may not have the drainage channels 96 shown, it should be understood that the bends of the bus bar 66 provide a tortuous path that prevents (e.g., prevents, blocks) corrosive agents or undesirable contaminants (e.g., water, air, fluids) from traveling along the bus bar and entering the polymer housing 30 of the battery module 20.

[0054] Figure 6 Before the terminal 60 is fixed to the bus bar 66 Figure 4 and 5, a perspective view of a bus bar 66 and a terminal post 60 of an embodiment of a terminal block assembly 58 is shown in FIG. As described above, the base 76 of the bus bar 66 defines an opening 74 that enables the post portion 68 of the terminal post 60 to extend through or through the base 76 of the bus bar 66. For example, the opening 74 may include a diameter 110 that is approximately equal to or slightly larger than the maximum diameter 112 of the post portion 68 of the terminal post 60. The bus bar 66 also includes a tab 78 that is designed to fold around certain sides 72 (e.g., perimeter) of the base portion 70 of the terminal post 60. For example, as described in detail below, the tab 78 can be folded around the sides 72 (e.g., perimeter) of the base 76 to enclose the base 76 within the cavity of the bus bar 70.

[0055] Figure 7 After the terminal 60 is secured to the bus bar 66 to form the electrical assembly 120 of the terminal block assembly 58 Figure 6 A perspective view of the bus bar 66 and the terminal 60 is shown in FIG. Figure 6 , the first post portion 68 of the terminal post 60 is inserted (e.g., threaded through, screwed into) through the opening 74 in the base 76 of the bus bar 66 until the base portion 70 of the terminal post 60 is substantially flush with the underside of the base 76 of the bus bar 66. Figure 7 As shown in FIG. 1 , the tabs 78 of the bus bar 66 can surround the base portion 70 of the terminal 60, as shown by arrows 122, thereby enclosing or retaining the base portion 70 within the cavity 124 of the bus bar 66). For example, in some embodiments, the tabs 78 can be heated to enhance flexibility and cause the tabs 78 to surround the base portion 70 of the terminal 60, thereby allowing the electrical assembly 120 (i.e., the bus bar 66 and the terminal 60) to be electrically connected without negatively affecting the integrity of the bus bar 66 and without the need to weld the bus bar 66 and the terminal 66 to each other. Alternatively, in some embodiments, the tabs 78 may be formed around the base portion 70 of the terminal 60 by a cold forming process in which the bus bar 66 is lubricated, the base portion 70 of the terminal 60 is positioned proximate to the underside of the base 76 of the bus bar 66, and the bus bar 66 is pushed or pulled through an opening in the cold formed molded part, which causes (e.g., forces, drives) the tabs 78 to bend around the base portion 70 of the terminal 60, thereby enclosing the base portion 70 through the cavity 124 of the bus bar 66. In some embodiments, the tabs 78 of the bus bar 66 may be stamped, pressed, or in some other manner adjusted into position around the base portion 70 of the terminal 60.

[0056] In certain embodiments, portions of the electrical component 120, including the bus bar 66 and / or the terminal post 60, may receive a microsurface treatment on at least the bonding surface of the electrical component 120 to increase the surface roughness prior to overmolding the bonding surface with the polymer portion 62 of the terminal land assembly 58. As used herein, for the bus bar 66 and / or the terminal post 60, "bonding surface" refers to the portion of the surface of the metal component that is in direct contact with and bonded to (e.g., adhered to, sealed to) the overmolded polymer portion 62 of the terminal land assembly 58. As used herein, "microsurface modification," "microsurface treatment," or "microsurface roughening" generally refers to a surface treatment that introduces micron-scale and / or submicron-scale (e.g., nanometer-scale) deformations (e.g., edges, depressions, peaks, ridges, grooves), generally referred to herein as "microsurface roughness," into at least the bonding surface of the electrical component 120, thereby increasing the surface roughness / surface area of ​​the treated surface. It is now recognized that this micro-surface treatment significantly improves the adhesion and sealing of the electrical components 120 that are overmolded into that portion of the enclosure of the battery module. Therefore, the present technology is particularly suitable for certain metal parts, such as some portions of the electrical components 120, which extend all the way through a portion of the polymer enclosure 30 and therefore risk compromising the desired waterproof seal of the enclosure 30 of the battery module 20.

[0057] In some embodiments, the entire surface of the electrical component 120 can receive a micro-surface treatment before or after the terminal 60 is fixed in the cavity 124 of the bus bar 66. In other embodiments, only the bonding surface 126 of the electrical component 120 (represented by the speckled texture) can be selectively treated with a micro-surface treatment before or after the terminal 60 is fixed in the cavity 124 of the bus bar 66. In still other embodiments, the electrical component 120 may not receive a micro-surface treatment before overmolding. It will be appreciated that in some embodiments, the micro-surface treatment may also be applied to at least some portions of the surface of the metal strip before the metal strip is shaped (e.g., stamped, pressed, bent, welded) to form the bus bar 66. Similarly, in some embodiments, the base portion 70 may receive a micro-surface treatment before being coupled to the column portion 68 to form the terminal 60.

[0058] In some embodiments, the etchant used for micro-surface treatment may include an acid, such as hydrochloric acid, sulfuric acid, acetic acid, nitric acid, hydrofluoric acid, or a mixture thereof. In other embodiments, the bonding surface 126 of the electrical component 120 may be roughened by laser etching, wherein electromagnetic radiation is used as an etchant. Generally, the etchant may be any etchant having the following capabilities: it provides suitable micron-scale and / or submicron-scale (e.g., nanometer-scale) features that significantly increase the micron-scale roughness of the exposed surface of the electrical component 120. In particular, for laser etching, it is easier to control which parts of the electrical component 120 are contacted by the etchant by controlling the laser, for example, thereby allowing only the bonding surface 126 of the electrical component 120 to be subjected to selective micro-surface treatment without using a mask. In other embodiments, before the micro-surface roughening treatment, a mask that is generally inert to the etchant may be temporarily disposed on multiple portions of the electrical component 120 to mask the underlying portion of the electrical component 120 so that it will not be roughened due to the treatment.

[0059] It is also recognized that in certain embodiments, the roughening effect provided by the microsurface treatment may be short-lived (e.g., hours to days or weeks) before the microsurface features may be significantly eroded due to slow oxidation of the microsurface features. Therefore, in certain embodiments, it may be desirable to overmold the electrical component 120 within a predetermined amount of time (e.g., on the order of minutes to hours or days to weeks) that the bus bar 66 and / or the terminal 60 are subjected to the microsurface treatment. In addition, it is understood that even if the non-bonding surface of the electrical component 120 is roughened by the microsurface treatment, the bonding surface buried under the polymer portion 62 during overmolding remains in a substantially roughened state, while the microsurface features added to the remaining surface of the electrical component 120 may gradually erode over time. Therefore, because masking the electrical component 120 adds additional cost, time, and complexity to the microsurface treatment process, in certain embodiments, it may be more cost-effective to roughen the entire surface of the electrical component 120, overmold the bonding surface of the electrical component with the polymer portion 62, and allow the roughness on the remaining surface of the electrical component 120 to gradually disappear.

[0060] Now turn Figure 8 and 9 , showing Figure 4 and 5 The wiring area assembly 58 is inserted into and positioned in the socket 64 of the housing 30. First, focus on Figure 8In the embodiment shown in FIG. 5 , as previously described, the socket 64 includes an angled or tapered surface 130 that corresponds to the angled or tapered surface 92 of the polymer portion 62 of the terminal block assembly 58. Thus, the polymer portion 62 can be easily received by the socket 64, and the tapered surfaces 92, 130 can physically contact each other, or reduce the amount of space between the housing 30 and the plastic portion 72 of the terminal block assembly 58 to less than the amount of space that would be present in the case of, for example, a conventional non-tapered terminal block assembly 58 and socket 64.

[0061] like Figure 8 As shown in , the socket 64 designed to receive the terminal block assembly 58 may include an opening 132 to receive the extension 86 of the bus bar 66. Thus, the opening 132 may be offset to compensate for the bend 85 in the bus bar 66 in order to properly receive the extension 86 of the terminal block assembly 58. In addition, as described in detail below, the lip 88 of the polymer portion 62 may be welded or adhered to one or more surfaces 135 of the housing 30 (e.g., where the surface 135 surrounds the socket 64) to seal the terminal block assembly 58 within the socket 64. As shown, the lip 88 may be welded to two surfaces 135 separated by a channel 137, where the channel 137 acts as a labyrinth to reduce the possibility of fluid leakage into or out of the socket 64.

[0062] Now turn Fig. 9 , the terminal block assembly 58 is shown as being sealed within the socket 64 of the housing 30 to form the main terminal 46 of the battery module 20. In order to seal the socket 64, the polymer portion 62 of the terminal block assembly 58 can be sealed (e.g., adhered, welded) to the housing 30. For example, as shown, the lip 88 of the polymer portion 62 can be welded to the housing 30 along the welding area 140 on the upper surface 142 of the polymer portion 62. In the illustrated embodiment, the lip 88 of the polymer portion 62 is welded along only one welding area 140. However, as described with respect to Figure 8 As described, the lip 88 of the polymer portion 62 can be welded to one or more surfaces of the housing 30 along multiple welding areas. In some embodiments, the polymer portion 62 and / or the housing 30 can additionally or alternatively be sealed in other ways (e.g., by covering or welding over the space 144 between the polymer portion 62 and the housing 30).

[0063] Fig.101 is a flowchart showing a process 150 for producing a battery module 20 according to an embodiment of the method of the present disclosure. It is understood that, according to the present disclosure, in other embodiments, certain steps may be performed in a different order, or certain steps may be omitted. The process 150 shown starts with performing a micro-surface treatment on one or more surfaces of the bus bar 66 and / or the terminal 60 (box 152). As described above, in some embodiments, the bus bar 66, the terminal 60, or both of the above can receive a micro-surface treatment on the entire surface of the metal part, while in other embodiments, only the bonding portion 126 of the electrical component 120 (e.g., including the lower side of the base 76, the inner and outer surfaces of the hairpin-shaped bend 84, and the inner and outer surfaces of the groove 80 of the bus bar 66) can receive a micro-surface treatment. For example, in some embodiments, the entire surface of the bus bar 66 and the base portion of the terminal 60 can receive a micro-surface treatment to improve adhesion to the polymer during a subsequent overmolding step. In other embodiments, the micro-surface treatment at box 152 can be omitted entirely.

[0064] Continuing with the illustrated process 150, the post portion 68 of the terminal post 60 is passed (block 154) through the opening 74 in the bus bar 66. As described above, in certain embodiments including a threaded post portion 68, the post portion 68 of the terminal post 60 can be threaded (e.g., twisted, rotated) through the opening 74 in the bus bar 66. Subsequently, one or more tabs 78 of the bus bar 66 are bent (block 156) to form the cavity 124 that secures the base portion 70 of the terminal post 60 to the bus bar 66, thereby forming the electrical assembly 120 of the terminal block assembly 58. As described above, when the tabs 78 are folded against the sides 72 of the base portion 70 of the terminal post 60, the cavity 124 formed by the tabs 78 inhibits or prevents the terminal post 60 from rotating or moving, thereby effectively securing the terminal post 60 to the bus bar 66.

[0065] Continuing with the illustrated process 150, a polymer is then overmolded around portions of the electrical assembly 120 (block 158) to form the terminal block assembly 58. As described above, the polymer portion 62 of the terminal block assembly 58 can overmold multiple surfaces of the bus bar 66 and the terminal post 60. The polymer portion 62 can further secure the base portion 70 of the terminal post 60 within the cavity 124 to inhibit or prevent the terminal post 60 from moving or rotating. The polymer portion 62 also overmolds at least a portion of the groove 80 of the bus bar 66 to form a drainage channel 96 of the terminal block assembly 58, which promotes fluid drainage from the terminal post 60, the electrochemical cell 32, and / or the circuit system of the battery module 20. In addition, in some embodiments, the polymer portion 62 can include a lip 88 that extends along the side 90 of the terminal block assembly 58 to enable the assembly to be sealed within the receptacle 64 of the housing 30 of the battery module 20. Additionally, as described, the terminal block assembly 58 may include tapered side portions 92 that correspond with tapered side portions 130 of the receptacle 64 of the housing 30 to further enhance the seal between the terminal block assembly 58 and the housing 30. It will be appreciated that in certain embodiments, the electrical component 120 may be retained in a particular position and the entire housing 30 of the battery module 20 (including the polymeric portion 62 of the terminal block assembly 58) may be overmolded around the electrical component 120 such that the housing 30 and the polymeric portion 62 are made of a single, unitary piece of polymeric material.

[0066] Next, in the illustrated process 150, the terminal block assembly 58 may be inserted (block 160) into the corresponding receptacle 64 of the housing 30 of the battery module 20. For example, in certain embodiments, this may include first lowering the extension 86 of the bus bar 66 into the receptacle 64, and then lowering the tapered side 92 of the terminal block assembly 58 to meet the corresponding tapered feature 130 within the receptacle 64 until the lip 88 extending from the side 90 of the terminal block assembly 58 contacts the outer surface 135 of the receptacle 64. The bus bar 66 may then be electrically coupled (block 162) to the power assembly 45 of the battery module 20. In certain embodiments, once the terminal block assembly 58 is loaded into the socket 64 of the battery module 20, the bus bar 66 can be electrically connected to the power assembly 45 by an extension 86 of the bus bar 66 directly contacting a metal slot within the socket, where the metal slot is electrically coupled to the power assembly 45 directly or indirectly (e.g., via a switch that can electrically disconnect the terminal block assembly 58 from the power assembly 45). In certain embodiments, the extension 86 of the bus bar 66 can be welded to a metal component (e.g., a secondary bus bar or a connector of the power assembly 45) that is electrically coupled to the power assembly 45 (e.g., directly or indirectly).

[0067] The illustrated process 150 ends with the terminal block assembly 58 being sealed (block 164) within the receptacle 64 of the housing of the battery module 20. For example, an adhesive, such as an epoxy or adhesive tape, may be used to seal the lip 88 of the terminal block assembly 58 to the outer surface 135 of the receptacle 64. In other embodiments, the lip 88 of the terminal block assembly 58 may be welded (e.g., ultrasonically welded, laser welded) to the outer surface 135 of the receptacle 64 to seal the terminal block assembly 58 within the receptacle 64.

[0068] Fig.11 is a perspective view of another embodiment of an electrical assembly 170, which can be used to produce Fig.12 and 13 An embodiment of the wiring area components 172 and 174 is shown in FIG. Fig.11 The electrical assembly 170 shown in FIG. 1 includes many of the same features as the bus bar 66 described above, which will not be described in detail. In addition, Fig.11 The bus bar 66 of the electrical assembly 170 shown in FIG. 1 also includes a deeper groove 80 (e.g., a U-shaped bend) disposed adjacent to the terminal 60. In addition, the bus bar 66 of the electrical assembly 170 also includes a hairpin bend 84 (e.g., an elongated U-shape) that extends in a direction opposite to the groove 84 to a height that is approximately equal or level with the base 76 of the bus bar 66. Thus, once the electrical assembly 170 is overmolded, as shown in FIG. Fig.12 As shown in Figure 4 The height of the rectangular portion 94 can be significantly reduced compared to the wiring area assembly 58. For example, Fig.12 The rectangular portion 94 of the terminal block assembly 172 is shorter, but still defines a drainage channel 96 near the terminal post 60. Fig.13 As shown in FIG. 1 , in some embodiments, the rectangular portion 94 may be eliminated entirely, thereby creating a substantially smooth region 176 disposed adjacent the terminal stud 60. Fig.13 The wiring area assembly 174 shown in FIG. 1 does not have the drainage channel 96, but it will be understood that Fig.11 The curved shape of the bus bar 66 of the electrical component 170 shown in FIG. 1 (e.g., bends 80 , 84 , and 85 ) still achieves a tortuous path that inhibits (e.g., prevents, blocks) corrosive agents or undesirable contaminants (e.g., water, air, fluids) from traveling along the bus bar 66 and entering the polymer housing 30 of the battery module 20 .

[0069] One or more embodiments of the present disclosure may provide one or more technical effects that contribute to the production of battery modules and some parts of battery modules, either individually or in combination. In general, embodiments of the present disclosure include a terminal block assembly having a bus bar, which encloses the base of the terminal post in a cavity of the bus bar, wherein the cavity is defined by a fin of the bus bar that is bent around the base of the terminal post. The cavity and the base are overmolded by the polymer base of the terminal block assembly, thereby forming a drainage channel of the terminal assembly adjacent to the base of the bus bar. Overmolding the cavity and the base by the polymer base enhances the ability of the terminal post to resist rotation when the lead is engaged with the terminal post. In addition, forming a terminal block assembly promotes modular production of the terminal block assembly, which can be easily positioned in the socket of the housing so that the electrical components of the terminal block assembly are electrically coupled to the electrochemical cells of the battery module. The polymer base of the terminal block assembly can also be welded and sealed to the polymer housing. The drainage channel of the terminal block assembly guides moisture or fluid away from the main terminals of the battery module, thereby extending the life of the main terminals and associated electrical connectors and helping to prevent fluid from entering the housing of the battery module. Therefore, the terminal posts of the battery module are easily integrated to reduce the flow of fluid into and out of the battery module via the housing. The technical effects and technical problems in this specification are exemplary and non-restrictive. It should be noted that the embodiments described in this specification may have other technical effects and may solve other technical problems.

[0070] The above specific embodiments have been shown by way of example, and it should be understood that these embodiments may have various modifications and alternative forms. It should also be understood that the claims are not intended to be limited to the specific forms disclosed, but are intended to cover all modifications, equivalents and alternatives that fall within the spirit and scope of the present disclosure.

Claims

1. A battery module, comprising: A terminal area assembly is secured to a polymer housing of the battery module, the terminal area assembly comprising: A terminal post having a terminal portion and a base portion extending outwardly from a central axis of the terminal portion; a bus bar coupled to the base portion of the terminal, the bus bar including a slot disposed adjacent the terminal; and a polymer portion overmolding the bus bar, The grooves of the bus bar form drainage channels near the terminals. 2 . The battery module of claim 1 , further comprising a polymer portion overmolding at least the groove of the bus bar to form a drainage channel adjacent the terminal post. 3 . The battery module of claim 1 , wherein the bus bar, the terminal post, or a combination thereof has micro surface roughness on portions of the bus bar that are overmolded by the polymer portion of the terminal area assembly.

4. The battery module according to claim 1, wherein the bus bar includes a first hairpin-shaped bend portion disposed adjacent to a first side of the groove and a second hairpin-shaped bend portion disposed adjacent to a second side of the groove opposite to the first side, wherein the first hairpin-shaped bend portion and the second hairpin-shaped bend portion extend in a direction opposite to the groove. 5 . The battery module of claim 1 , wherein the bus bar comprises copper, aluminum, nickel, stainless steel, or a combination thereof, and wherein the terminal comprises copper, aluminum, nickel, stainless steel, or a combination thereof. The battery module according to claim 5 , wherein the bus bar and the terminal are made of different materials.

7. A battery module according to claim 1, wherein the bus bar includes an opening and one or more fins surrounding the opening, wherein the post portion of the terminal extends through the opening of the bus bar, and wherein the one or more fins of the bus bar are bent around the base portion of the terminal to retain the base portion within a cavity of the bus bar. 8 . The battery module of claim 7 , wherein the polymer portion of the terminal block assembly over-molds the base portion of the terminal post to further secure the terminal post within the cavity of the bus bar. 9 . The battery module of claim 1 , wherein the polymer portion includes a lip that is sealed to an outer surface of the polymer housing around a socket.

10. The battery module of claim 9, comprising a weld coupling the lip of the polymer portion to the outer surface of the polymer housing surrounding the socket. The battery module of claim 1 , wherein the polymer portion is integral with the polymer housing. 12 . The battery module of claim 1 , wherein the groove is a U-shaped groove disposed near an interface between the polymer portion and an exposed base of the bus bar surrounding the terminal.

13. The battery module of claim 1, wherein the groove, the drainage channel, or both the groove and the drainage channel are configured to prevent fluid from pooling near the terminal or to prevent fluid from draining toward an electrochemical cell or circuit system of the battery module.

14. A battery module, comprising: a terminal block assembly defining main terminals of the battery module and secured to a polymer housing of the battery module, the terminal block assembly comprising: A terminal post having a terminal portion and a base portion extending outwardly from a central axis of the terminal portion; a bus bar physically coupled to the base portion of the terminal, the bus bar electrically coupled to a plurality of first battery cell terminals of a plurality of lithium ion battery cells disposed in a waterproof interior volume of the polymer housing, and the bus bar comprising a U-shaped groove disposed adjacent the terminal, the U-shaped groove disposed between a first hairpin bend and a second hairpin bend, wherein the first hairpin bend and the second hairpin bend extend in a direction opposite to the U-shaped groove and extend above a plane of the base portion of the terminal; and A polymer portion, wherein the polymer portion overmoldes the U-shaped groove of the bus bar, wherein the U-shaped groove forms a drainage channel near the terminal post, and the U-shaped groove is disposed near an interface between the polymer portion and an exposed base of the bus bar surrounding the terminal post, wherein the exposed base of the bus bar is not overmolded by the polymer portion. 15 . The battery module of claim 14 , further comprising a polymer portion overmolding at least the U-shaped groove and the first and second hairpin bends of the bus bar to form a drainage channel near the terminal post. 16 . The battery module of claim 14 , wherein the bus bar, the terminal post, or a combination thereof has micro surface roughness on portions of the bus bar that are overmolded by the polymer portion of the terminal area assembly. 17 . The battery module of claim 14 , wherein the bus bar comprises copper, aluminum, nickel, stainless steel, or a combination thereof, and wherein the terminal comprises copper, aluminum, nickel, stainless steel, or a combination thereof. 18 . The battery module according to claim 17 , wherein the bus bar is made of a first metal and the terminal is made of a second metal different from the first metal.

19. A battery module according to claim 14, wherein the bus bar includes an opening and one or more fins surrounding the opening, wherein the post portion of the terminal extends through the opening of the bus bar, and wherein the one or more fins of the bus bar are bent around the base portion of the terminal to retain the base portion within a cavity of the bus bar.

20. The battery module of claim 19, wherein the polymer portion of the terminal block assembly over-molds the base portion of the terminal post to further secure the terminal post within the cavity of the bus bar.

21. The battery module of claim 14, wherein the polymer portion includes a lip that is sealed to an outer surface of the polymer housing around a socket of the polymer housing.

22. The battery module of claim 21, comprising a weld coupling the lip of the polymer portion to the outer surface of the polymer housing surrounding the socket of the polymer housing.

23. The battery module of claim 14, wherein the polymer portion is integral with the polymer housing.

24. The battery module of claim 14, wherein the U-shaped groove, the drainage channel, or both the U-shaped groove and the drainage channel are configured to prevent fluid from pooling near the terminal or to prevent fluid from discharging toward an electrochemical battery cell or circuit system of the battery module.

25. The battery module of claim 14, comprising an additional terminal block assembly defining a second main terminal of the battery module and secured to the polymer housing of the battery module, the additional terminal block assembly comprising: a second terminal post having a second terminal portion and a second base portion extending outwardly from a central axis of the second terminal portion; a second bus bar physically coupled to the second base portion of the second terminal, wherein the second bus bar is electrically coupled to a plurality of second battery cell terminals of the plurality of lithium ion battery cells disposed in the waterproof interior volume of the polymer housing, and wherein the second bus bar includes a second U-shaped groove disposed adjacent the second terminal, the second U-shaped groove being disposed between a third hairpin bend and a fourth hairpin bend, wherein the third hairpin bend and the fourth hairpin bend extend in a direction opposite to the second U-shaped groove and extend above a plane of the second base portion of the second terminal; and A second polymer portion overmoldes at least the second U-shaped groove and the third and fourth hairpin bends to form a second drainage channel adjacent the second terminal.

26. A battery module, comprising: a polymer housing defining a waterproof interior volume and a first receptacle; a plurality of lithium-ion battery cells disposed within the waterproof interior volume of the polymer housing; as well as A first terminal block assembly is sealed in the first socket of the polymer housing to define a first main terminal of the battery module, wherein the first terminal block assembly includes: a first terminal post having a first terminal portion and a first base portion extending outwardly from a central axis of the first terminal portion; a first bus bar mechanically coupled to the first base portion, wherein the first bus bar includes a first U-shaped groove disposed adjacent the first terminal, the first U-shaped groove disposed between a first hairpin bend and a second hairpin bend, wherein the first hairpin bend and the second hairpin bend extend in a direction opposite to the first U-shaped groove and extend above a plane of the first base portion of the first terminal, and wherein the first bus bar is electrically coupled to a plurality of first battery cell terminals of the plurality of lithium ion battery cells; and A first polymer portion, the first polymer portion overmolding at least the first hairpin bend and the second hairpin bend and the first U-shaped groove to form a first drainage channel near the first terminal, wherein the U-shaped groove is disposed near an interface between the polymer portion and an exposed base of the bus bar surrounding the terminal, wherein the exposed base of the bus bar is not overmolded by the polymer portion.

27. The battery module of claim 26, wherein the polymer housing defines a second socket, and wherein the battery module includes a second terminal block assembly sealed within the second socket of the polymer housing, wherein the second terminal block assembly includes: a second terminal post having a second terminal portion and a second base portion extending outwardly from a central axis of the second terminal portion; a second bus bar mechanically coupled to the second base portion, wherein the second bus bar includes a second U-shaped groove disposed adjacent the second terminal, the second U-shaped groove disposed between a third hairpin bend and a fourth hairpin bend, wherein the third hairpin bend and the fourth hairpin bend extend in a direction opposite to the second U-shaped groove and extend above a plane of the second base portion of the second terminal, and wherein the second bus bar is electrically coupled to a plurality of second battery cell terminals of the plurality of lithium ion battery cells; and A second polymer portion overmoldes at least the third and fourth hairpin bends and the second U-shaped groove to form a second drainage channel adjacent the second terminal.

28. The battery module of claim 26, wherein the first post portion is a threaded post, a smooth post, or a flange.

29. The battery module of claim 26, wherein the first polymer portion includes a tapered side portion, and wherein the first receptacle includes a corresponding tapered side portion to receive the tapered side portion of the first polymer portion.

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