Patent Description:
A vehicle that uses one or more battery systems for providing all or a portion of the motive power for the vehicle can be referred to as an xEV, where the term "xEV" is defined herein to include all of the following vehicles, or any variations or combinations thereof, that use electric power for all or a portion of their vehicular motive force. For example, xEVs include electric vehicles (EVs) that utilize electric power for all motive force. As will be appreciated by those skilled in the art, hybrid electric vehicles (HEVs), also considered xEVs, combine an internal combustion engine propulsion system and a battery-powered electric propulsion system, such as <NUM> Volt (V) or 130V systems. The term HEV may include any variation of a hybrid electric vehicle. For example, full hybrid systems (FHEVs) may provide motive and other electrical power to the vehicle using one or more electric motors, using only an internal combustion engine, or using both. In contrast, mild hybrid systems (MHEVs) disable the internal combustion engine when the vehicle is idling and utilize a battery system to continue powering the air conditioning unit, radio, or other electronics, as well as to restart the engine when propulsion is desired. The mild hybrid system may also apply some level of power assist, during acceleration for example, to supplement the internal combustion engine. Mild hybrids are typically 96V to 130V and recover braking energy through a belt or crank integrated starter generator. Further, a micro-hybrid electric vehicle (mHEV) also uses a "Stop-Start" system similar to the mild hybrids, but the micro-hybrid systems of a mHEV may or may not supply power assist to the internal combustion engine and operates at a voltage below 60V. For the purposes of the present discussion, it should be noted that mHEVs typically do not technically use electric power provided directly to the crankshaft or transmission for any portion of the motive force of the vehicle, but an mHEV may still be considered as an xEV since it does use electric power to supplement a vehicle's power needs when the vehicle is idling with internal combustion engine disabled 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 source of electricity, such as wall sockets, and the energy stored in the rechargeable battery packs drives or contributes to drive the wheels. PEVs are a subcategory of EVs that include all-electric or battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs), and electric vehicle conversions of hybrid electric vehicles and conventional internal combustion engine vehicles.

xEVs as described above may provide a number of advantages as compared to more traditional gas-powered vehicles using only internal combustion engines and traditional electrical systems, which are typically 12V systems powered by a lead acid battery. For example, xEVs may produce fewer undesirable emission products and may exhibit greater fuel efficiency as compared to traditional internal combustion vehicles and, in some cases, such xEVs may eliminate the use of gasoline entirely, as is the case of certain types of EVs or PEVs.

As technology continues to evolve, there is a need to provide improved power sources, particularly battery modules, for such vehicles. For example, in traditional configurations, battery modules may include a number of interconnected electrochemical cells coupled together via bus bars (e.g., minor bus bars) extending between terminals (e.g., minor terminals or cell terminals) of the electrochemical cells. Further, the battery module may include two major terminals electrically coupled with the interconnected electrochemical cells via corresponding electrical paths, each electrical path having a major bus bar extending from the major terminal between the major terminal and the minor terminal of one of the electrochemical cells. This enables the two major terminals to be coupled to a load for powering the load via electric power provided by the interconnected electrochemical cells. In traditional configurations, each major bus bar and corresponding major terminal of the battery module may be welded together to establish at least a portion of the electrical path between the major terminal and the minor terminal, which may require that the major bus bar and the major terminal are made of the same material, or at least compatible materials for welding. The welding steps and use of specific materials may result in a high cost of the battery module. Further, traditional configurations requiring extensive welding may be bulky, which may reduce an energy density of the battery module. Accordingly, it is now recognized that an improved major bus bar and major terminal (and assembly thereof) for battery modules is needed.

Document <CIT> represents a close prior art.

The invention is detailed in the appended claims.

The present disclosure relates to a battery module that includes an electrochemical cell having a minor terminal. The battery module also includes a major terminal electrically coupled to the electrochemical cell, wherein the major terminal includes a base and a post extending from the base. Further, the battery module includes an electrical path between the minor terminal of the electrochemical cell and the major terminal of the battery module. The electrical path includes a bus bar having an opening that receives the post of the major terminal and a pocket that retains the base of the major terminal.

The present disclosure also relates to a method of manufacturing a battery module that includes disposing a post of a module terminal through an opening in a bus bar. The method also includes wrapping a first extension of the bus bar from a first surface of a base of the module terminal to a second surface of the base opposite to the first surface.

The present disclosure also relates to a battery module that includes a first electrochemical cell having a first terminal, a second electrochemical cell having a second terminal, and one or more intermediate electrochemical cells electrically connected between, and to, the first electrochemical cell and the second electrochemical cell. The battery module includes a first electrical path extending between the first terminal of the first electrochemical cell and a first major terminal of the battery module and comprising a first major bus bar. The first major terminal includes a first post that extends through a first opening in the first major bus bar, and a first base that is coupled to the first post and retained within a first pocket of the first major bus bar at least partially defined by one or more first extensions of the first major bus bar that wrap around the first base of the first major terminal. The battery module further includes a second electrical path extending between the second terminal of the electrochemical cell and a second major terminal of the battery module and comprising a second major bus bar. The second major terminal includes a second post that extends through a second opening in the second major bus bar, and a second base that is coupled to the second post and retained within a second pocket of the second major bus bar at least partially defined by one or more second extensions of the second major bus bar that wrap around the second base of the second major terminal.

It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and businessrelated constraints, which may vary from one implementation to another.

The battery systems described herein may be used to provide power to various types of electric vehicles (xEVs) and other high voltage energy storage/expending applications (e.g., electrical grid power storage systems). Such battery systems may include one or more battery modules, each battery module having a number of battery cells (e.g., lithium-ion (Li-ion) electrochemical cells) arranged and electrically interconnected to provide particular voltages and/or currents useful to power, for example, one or more components of an xEV. As another example, battery modules in accordance with present embodiments may be incorporated with or provide power to stationary power systems (e.g., non-automotive systems).

During assembly of a battery module, the individual electrochemical cells may be positioned in a housing of the battery module, and terminals (e.g., minor terminals or cell terminals) of the electrochemical cells may extend generally away from the housing. To couple the electrochemical cells together (e.g., in series or parallel), an electrical path between minor terminals of two or more electrochemical cells may be established by coupling pairs of minor terminals via corresponding bus bars (e.g., minor bus bars). Further, two of the electrochemical cells (e.g., on either end of the battery module or on ends of one or more stacks of electrochemical cells) may be electrically coupled to major terminals (e.g., module terminals or primary terminals) of the battery module via corresponding major bus bars, or via corresponding major bus bar assemblies, where the major terminals are configured to be coupled to a load for powering the load. In traditional configurations, to ensure that the major terminals and their associated major bus bars do not become decoupled, the major terminals and major bus bars may be welded together. However, welding of the major terminal and the major bus bar may require that the material of the major bus bar is the same as the material of the major terminal, or at least compatible for welding. Further, the material of the major bus bars may depend on the material of the corresponding minor terminals (e.g., of the electrochemical cells) from which the major bus bars extend, or on the material of one or more intervening components (e.g., a shunt coupled to a printed circuit board (PCB <NUM>)). This may increase a material cost of the battery module and complexity of manufacturing. Further, associated geometries, assemblies, and welding techniques for traditional configurations such as those described above may contribute to a volume of the battery module, thereby reducing an energy density of the battery module.

To address these and other shortcomings of traditional battery module configurations, battery modules in accordance with the present disclosure include major terminals and major bus bars having similar or dissimilar materials, where the major terminals and major bus bars are coupled together without welding. For example, each major terminal (e.g., on either side of the battery module or stacks of electrochemical cells) may include a base and a post extending from the base. A corresponding major bus bar extending from the major terminal may be a flat sheet (or initially a flat sheet) with an opening configured to receive the post of the major terminal. Generally, the flat sheet is capable of being wrapped around at least a portion of the major terminal (e.g., at least the base). For instance, the flat sheet of the major bus bar may include flaps extending from a body (e.g., a rectangular body) of the flat sheet. After extending the post of the major terminal through the opening in the flat sheet (which is the major bus bar), the flaps may be wrapped around the base of the major terminal to envelop or retain the base. For example, the flaps may be heated to enhance pliability and enable wrapping of the flaps around the base of the major terminal, thereby enabling the major bus bar and the major terminal to be electrically connected without negatively affecting the integrity of the major bus bar, and without welding. The flaps of the major bus bar may be stamped, pressed, or maneuvered in some other manner in place around the base of the major terminal.

Further, the base of the major terminal may be square or rectangular in shape (or include a square or rectangular portion), which enables resistance (e.g., via contact between the base of the major terminal and the flaps of the major bus bar wrapped around the base) to torque applied to the post of the major terminal. Further still, after wrapping the flaps of the major bus bar around the base of the major terminal, a lower portion of the combined major bus bar and major terminal (e.g., lower portion including the base and the wrapped flaps) may be embedded in a wall of a plastic housing of the battery module. For example, the lower portion of the combined major bus bar and major terminal may be injection molded with the plastic housing. Accordingly, the lower portion of the combined major bus bar and major terminal may be embedded within the housing in a number of orientations, and an electrical path from the major terminal to a corresponding minor terminal of an electrochemical cell (e.g., the electrical path including the major bus bar) may be adapted and/or configured based on the orientation of the major terminal. These and other features will be described in further detail below.

To help illustrate, <FIG> is a perspective view of an embodiment of a vehicle <NUM>, which may utilize a regenerative braking system. Although the following discussion is presented in relation to vehicles with regenerative braking systems, the techniques described herein are adaptable to other vehicles that capture/store electrical energy with a battery, which may include electric-powered and gas-powered vehicles.

As discussed above, it would be desirable for a battery system <NUM> to be largely compatible with traditional vehicle designs. Accordingly, the battery system <NUM> may be placed in a location in the vehicle <NUM> that would have housed a traditional battery system. For example, as illustrated, the vehicle <NUM> may include the battery system <NUM> positioned similarly to a lead-acid battery of a typical combustion-engine vehicle (e.g., under the hood of the vehicle <NUM>). Furthermore, as will be described in more detail below, the battery system <NUM> may be positioned to facilitate managing temperature of the battery system <NUM>. For example, in some embodiments, positioning a battery system <NUM> under the hood of the vehicle <NUM> may enable an air duct to channel airflow over the battery system <NUM> and cool the battery system <NUM>.

In other words, the battery system <NUM> may supply power to components of the vehicle's electrical system, which may include radiator cooling fans, climate control systems, electric power steering systems, active suspension systems, auto park systems, electric oil pumps, electric super/turbochargers, electric water pumps, heated windscreen/defrosters, window lift motors, vanity lights, tire pressure monitoring systems, sunroof motor controls, power seats, alarm systems, infotainment systems, navigation features, lane departure warning systems, electric parking brakes, external lights, or any combination thereof. Illustratively, in the depicted embodiment, the energy storage component <NUM> supplies power to the vehicle console <NUM> and the ignition system <NUM>, which may be used to start (e.g., crank) the internal combustion engine <NUM>.

Additionally, the energy storage component <NUM> may capture electrical energy generated by the alternator <NUM> and/or the electric motor <NUM>. In some embodiments, the alternator <NUM> may generate electrical energy while the internal combustion engine <NUM> is running. More specifically, the alternator <NUM> may convert the mechanical energy produced by the rotation of the internal combustion engine <NUM> into electrical energy. Additionally or alternatively, when the vehicle <NUM> includes an electric motor <NUM>, the electric motor <NUM> may generate electrical energy by converting mechanical energy produced by the movement of the vehicle <NUM> (e.g., rotation of the wheels) into electrical energy. Thus, in some embodiments, the energy storage component <NUM> may capture electrical energy generated by the alternator <NUM> and/or the electric motor <NUM> during regenerative braking. As such, the alternator <NUM> and/or the electric motor <NUM> are generally referred to herein as a regenerative braking system.

To facilitate capturing and supplying electric energy, the energy storage component <NUM> may be electrically coupled to the vehicle's electric system via a bus <NUM>. For example, the bus <NUM> may enable the energy storage component <NUM> to receive electrical energy generated by the alternator <NUM> and/or the electric motor <NUM>. Additionally, the bus <NUM> may enable the energy storage component <NUM> to output electrical energy to the ignition system <NUM> and/or the vehicle console <NUM>. Accordingly, when a <NUM> volt battery system <NUM> is used, the bus <NUM> may carry electrical power typically between <NUM>-<NUM> volts.

Additionally, as depicted, the energy storage component <NUM> may include multiple battery modules. For example, in the depicted embodiment, the energy storage component <NUM> includes a lithium ion (e.g., a first) battery module <NUM> and a lead-acid (e.g., a second) battery module <NUM>, which each includes one or more battery cells. In other embodiments, the energy storage component <NUM> may include any number of battery modules. Additionally, although the lithium ion battery module <NUM> and lead-acid battery module <NUM> are depicted adjacent to one another, they may be positioned in different areas around the vehicle. For example, the lead-acid battery module <NUM> may be positioned in or about the interior of the vehicle <NUM> while the lithium ion battery module <NUM> may be positioned under the hood of the vehicle <NUM>.

In some embodiments, the energy storage component <NUM> may include multiple battery modules to utilize multiple different battery chemistries. For example, when the lithium ion battery module <NUM> is used, performance of the battery system <NUM> may be improved since the lithium ion battery chemistry generally has a higher coulombic efficiency and/or a higher power charge acceptance rate (e.g., higher maximum charge current or charge voltage) than the lead-acid battery chemistry. As such, the capture, storage, and/or distribution efficiency of the battery system <NUM> may be improved.

To facilitate controlling the capturing and storing of electrical energy, the battery system <NUM> may additionally include a control module <NUM>. More specifically, the control module <NUM> may control operations of components in the battery system <NUM>, such as relays (e.g., switches) within energy storage component <NUM>, the alternator <NUM>, and/or the electric motor <NUM>. For example, the control module <NUM> may regulate amount of electrical energy captured/supplied by each battery module <NUM> or <NUM> (e.g., to de-rate and re-rate the battery system <NUM>), perform load balancing between the battery modules <NUM> and <NUM>, determine a state of charge of each battery module <NUM> or <NUM>, determine temperature of each battery module <NUM> or <NUM>, control voltage output by the alternator <NUM> and/or the electric motor <NUM>, and the like.

Accordingly, the control unit <NUM> may include one or more processor <NUM> and one or more memory <NUM>. More specifically, the one or more processor <NUM> 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. Additionally, the one or more memory <NUM> may include volatile memory, such as random access memory (RAM), and/or non-volatile memory, such as read-only memory (ROM), optical drives, hard disc drives, or solid-state drives. In some embodiments, the control unit <NUM> may include portions of a vehicle control unit (VCU) and/or a separate battery control module.

An exploded perspective view of an embodiment of the battery module <NUM> (e.g., lithium-ion (Li-ion) battery module) is shown in <FIG>. In the illustrated embodiment, the battery module <NUM> includes a housing <NUM> configured to store electrochemical cells <NUM> within an interior <NUM> of the housing <NUM>. In the illustrated embodiment, the electrochemical cells <NUM> are stored in two stacks <NUM> within the interior <NUM> of the housing <NUM>, where the two stacks <NUM> are separated by a partition <NUM>. However, the electrochemical cells <NUM> may be housed in the interior <NUM> of the housing <NUM> in fewer or more than two stacks <NUM> (e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or more stacks <NUM>), and the electrochemical cells <NUM> may be oriented within the interior <NUM> of the housing <NUM> vertically, horizontally, or otherwise.

Each electrochemical cell <NUM> may include two terminals <NUM> (e.g., minor terminals or cell terminals). For clarity, the terminals <NUM> of the electrochemical cells <NUM> will be referred to herein as minor terminals <NUM>. The minor terminals <NUM> of adjacent electrochemical cells <NUM> are coupled together in series via bus bars <NUM> (e.g., minor bus bars or cell bus bars). For clarity, the bus bars <NUM> configured to couple the minor terminals <NUM> of adjacent electrochemical cells <NUM> will be referred to herein as minor bus bars <NUM>. In the illustrated embodiment, the minor bus bars <NUM> may be installed or otherwise disposed in (or on) a carrier <NUM> configured to hold or facilitate coupling between the minor bus bars <NUM> and other electrical components (e.g., voltage or temperature sensors or leads thereof). For example, the carrier <NUM> may include recesses <NUM> configured to receive the minor bus bars <NUM>, where openings <NUM> are disposed in the recesses <NUM> for receiving the minor terminals <NUM> of the electrochemical cells <NUM>. Accordingly, the minor bus bars <NUM> are disposed in the recesses <NUM> and the terminals <NUM> extend through the openings <NUM> into contact with the minor bus bars <NUM>. In other embodiments, the minor bus bars <NUM> may not include the openings <NUM>, and the terminals <NUM> may contact a flat surface of the minor bus bars <NUM>.

The minor bus bars <NUM> establish an aggregate network of interconnected electrochemical cells <NUM> by coupling minor terminals <NUM> of adjacent electrochemical cells <NUM>, where the aggregate network of interconnected electrochemical cells <NUM> enables an aggregate charge provided to charge a load. For example, electrical paths <NUM> may be defined on either side of the aggregate network of interconnected electrochemical cells <NUM>, where the electrical paths <NUM> include terminals <NUM> (e.g., major terminals or module terminals) of the battery module <NUM> that couple with the load to supply the load with the aggregate charge from the interconnected electrochemical cells <NUM>.

For example, in the illustrated embodiment, the electrical paths <NUM> each include a bridge <NUM>, each bridge <NUM> being coupled to a corresponding minor bus bar <NUM>. In some embodiments, the corresponding minor bus bar <NUM> may be a bi-metal bus bar having a first end <NUM> with a first material corresponding to a material of the minor terminal <NUM> in contact with the first end <NUM>, and a second end <NUM> in contact with the bridge <NUM> and having a second material corresponding to a material of the bridge <NUM>. This may enable a transition from the material of the terminals <NUM> (e.g., aluminum) to a different material (e.g., copper). The transition may facilitate the use of a shunt <NUM> or some other component (e.g., a relay component) that is coupled to (e.g., welded to) the bridge <NUM> and is in electrical communication with a printed circuit board (PCB) <NUM> of the battery module <NUM>. For example, the shunt <NUM> may be in electrical communication with the PCB <NUM> via sensors and corresponding leads extending from the sensors, where the sensors provide measurements of parameters (e.g., voltage and/or temperature) monitored for control of the battery module <NUM>. Generally, the shunt <NUM> and/or relay components are a certain material (e.g., copper) that enables appropriate measurement and/or sensing of voltage parameters, temperature parameters, and/or other parameters relating to operating conditions of the battery module <NUM>. Further, in some embodiments, the shunt <NUM> and the bridge <NUM> may be one integral component.

In accordance with the present disclosure, the bridges <NUM> are also in electrical communication with the corresponding terminals <NUM> (e.g., major terminals or module terminals) of the battery module <NUM> to establish the corresponding electrical paths <NUM> between the terminals <NUM> of the battery module <NUM> and the minor terminals <NUM> of the electrochemical cells <NUM>. For clarity, the terminals <NUM> of the battery module <NUM> will be referred to as major terminals <NUM> herein (e.g., to differentiate from the minor terminals <NUM> of the electrochemical cells <NUM>). Each major terminal <NUM> may be partially embedded within a wall of the housing <NUM> of the battery module <NUM>, along with at least a portion of a corresponding bus bar <NUM> (e.g., major bus bar) of the battery module <NUM>. In some embodiments, only a portion of the corresponding bus bar <NUM> (e.g., major bus bar) may be embedded in the housing <NUM>. The corresponding bus bar <NUM> (e.g., major bus bar) may be coupled (e.g., directly or indirectly) to the corresponding bridge <NUM>, which is in electrical communication with the corresponding minor bus bar <NUM> and, thus, with the corresponding minor terminal <NUM> of the corresponding electrochemical cell <NUM>. For clarity, the bus bars <NUM> of the battery module <NUM> will be referred to herein as major bus bars <NUM> (e.g., to differentiate from the minor bus bars <NUM> on the carrier <NUM>).

Each major bus bar <NUM> includes portions wrapped around a base of the corresponding major terminal <NUM>, and an opening configured to receive a post of the corresponding major terminal <NUM>, thereby enabling the major bus bar <NUM> to retain the major terminal <NUM> without welding the two components together. In other words, the coupling between the major terminal <NUM> and the major bus bars <NUM> may be physical only, as opposed to physical and metallurgical as would be the case with welding. For example, each of the two major bus bars <NUM> may include one or more flaps or extensions folded and/or stamped around a base of the major terminal <NUM> to enable a pocket <NUM> proximate or between the one or more folded flaps, where the pocket <NUM> is configured to hold the base of the major terminal <NUM>. Thus, while the major bus bars <NUM> may include a material corresponding to the material of the bridges <NUM> (e.g., copper) such that the major bus bars <NUM> may be welded to the bridges <NUM>, the major terminals <NUM> may include a different material since welding between the major terminals <NUM> and the major bus bars <NUM> is not needed. The major terminal <NUM>, for example, may include stainless steel, which facilitates reduced material cost, increased case of manufacturing, and durability. These and other features of the major terminals <NUM> and the major bus bars <NUM> will be described in detail below.

It should be noted that the two illustrated electrical paths <NUM> may include additional or fewer components depending on the embodiment of the battery module <NUM>. For example, in the illustrated embodiment, the major terminals <NUM> of the battery module <NUM> extend in direction <NUM>. The electrical path <NUM> extending from the minor terminal <NUM> of the electrochemical cell <NUM> to the major terminal <NUM> of the battery module <NUM> includes the bi-metal bus bar <NUM>, the bridge <NUM>, and the major bus bar <NUM>. Further, the electrical path <NUM> may include a portion of the shunt <NUM> between (e.g., sandwiched between) the bridge <NUM> and the major bus bar <NUM>. However, in other embodiments, it may be desirable for the major terminals <NUM> to extend in a different direction, e.g., in direction <NUM> (e.g., the same direction as the cell terminals <NUM>). For example, extending the major terminals <NUM> in a particular direction (e.g., directions <NUM> or <NUM>) may facilitate case of coupling with a load. Depending on the direction of the major terminals <NUM>, embodiments may include more components, fewer components, or different components in the electrical path <NUM> to establish electrical communication between the minor terminal <NUM> of the electrochemical cell <NUM> and the major terminal <NUM> of the battery module <NUM>. These and other features will be described in detail below with reference to later figures, namely, <FIG> and <FIG>.

The manner in which the major terminals <NUM> and the major bus bars <NUM> are coupled together may be further appreciated with reference to <FIG>, which depict various stages of coupling the features together. Specifically, <FIG> is an exploded perspective view of an embodiment of one of the major terminals <NUM> and one of the major bus bars <NUM> (e.g., before or during assembly). In the illustrated embodiment, the major terminal <NUM> includes a post <NUM> extending from a cylindrical portion <NUM> of a base <NUM> of the major terminal <NUM>. For example, the post <NUM> may be integrally formed with the cylindrical portion <NUM>, or the post <NUM> may be otherwise coupled to the cylindrical portion <NUM> via adhesive, welding, one or more fasteners, or some other suitable coupling mechanism. The base <NUM> also includes a rectangular portion <NUM> with an opening <NUM> configured to receive the cylindrical portion <NUM>. For example, a diameter <NUM> of the cylindrical portion <NUM> may correspond to a diameter <NUM> of the opening <NUM> in the rectangular portion <NUM>. The cylindrical portion <NUM> may be coupled to the rectangular portion <NUM> at the opening <NUM> via adhesive, welding (e.g., resistance or laser welding), one or more fasteners, or some other coupling mechanism. Further, in some embodiments, the opening <NUM> in the rectangular portion <NUM> may be configured to receive the post <NUM> of the major terminal <NUM> as opposed to the cylindrical portion <NUM>. For example, the diameter <NUM> of the opening <NUM>, in another embodiment, may correspond to a diameter <NUM> of the post <NUM>, and the post <NUM> may be coupled to the rectangular portion <NUM> at the opening <NUM> via adhesive, welding (e.g., resistance or laser welding), one or more fasteners, or some other coupling mechanism. Further still, in some embodiments, the base <NUM> may include only a rectangular portion coupled to (e.g., via adhesive, welding, fasteners, or any other suitable coupling method) or integrally formed with the post <NUM>.

The major bus bar <NUM>, before assembly, is a generally flat member that may be cut from sheet metal or formed via a cutting or casting process. The major bus bar <NUM>, in the illustrated embodiment, includes an opening <NUM> configured to receive the post <NUM> of the major terminal <NUM>. For example, the opening <NUM> may include a diameter <NUM> corresponding to the diameter <NUM> of the post <NUM>. The opening <NUM> extends through a main body <NUM> of the major bus bar <NUM>. The opening <NUM> may be cut, punched, or otherwise disposed in the main body <NUM> of the major bus bar <NUM>.

The major bus bar <NUM> also includes flaps <NUM> extending from the main body <NUM>. Before assembly, the flaps <NUM> may extend generally parallel with the main body <NUM> of the major bus bar <NUM>. The major bus bar <NUM> may include three flaps <NUM>, as shown, or the major bus bar <NUM> may include less than or more than three flaps <NUM>. For example, in some embodiments, the major bus bar <NUM> may only include a primary flap <NUM> extending from the main body <NUM>, where the primary flap <NUM> and the main body <NUM> together form, e.g., a rectangular or square prism. In general, the flaps <NUM> (including the primary flap <NUM>) of the major bus bar <NUM>, during assembly, are folded over at least a portion of the base <NUM> of the major terminal <NUM> after the post <NUM> of the major terminal <NUM> is pushed, extended, or disposed through or in the opening <NUM> of the major bus bar <NUM> (e.g., as shown in <FIG>).

For example, the flaps <NUM> may be folded from or proximate a top surface <NUM> of the base <NUM> around or proximate a side surface <NUM> of the base <NUM>. One or more of the flaps <NUM> (e.g., the primary flap <NUM>) may also fold under a bottom surface <NUM> of the base <NUM>. The top and bottom surfaces <NUM>, <NUM> may extend across both the cylindrical and rectangular portions <NUM>, <NUM> of the base <NUM>, and the side surfaces <NUM> may extend between the top and bottom surfaces <NUM>, <NUM> along the rectangular portion <NUM> of the base <NUM>. As a result of this folding, the flaps <NUM> (and a portion of the main body <NUM>), form the pocket <NUM> configured to retain the base <NUM> (e.g., as shown in <FIG>). Because the base <NUM> includes the rectangular portion <NUM>, torque applied to the post <NUM> of the major terminal <NUM> is generally resisted via contact between the rectangular portion <NUM> of the major terminal <NUM> and the flaps <NUM> of the major bus bar <NUM>. Put differently, if the base <NUM> of the major terminal <NUM> only included the cylindrical portion <NUM> (e.g., without the rectangular portion <NUM>), torque applied to the post <NUM> of the major terminal <NUM> (e.g., applied when coupling leads to the post <NUM>) may cause the post <NUM> and the base <NUM> to turn, because the base <NUM> would not include abutment surfaces that resist rotation of the base <NUM> within the pocket <NUM> (e.g., as shown in <FIG>).

During assembly, as previously described, the post <NUM> may be pushed or extended through the opening <NUM> in the main body <NUM> of the major bus bar <NUM>. The flaps <NUM> may then be stamped or pressed around at least a portion of the base <NUM> for retaining the base <NUM>, as previously described. For example, an embodiment of the major bus bar <NUM> and the major terminal <NUM> during assembly is shown in a perspective view in <FIG>. In the illustrated embodiment, the post <NUM> extends through the opening <NUM> in the main body <NUM> of the major bus bar <NUM>, and two of the flaps <NUM> (e.g., not the primary flap <NUM>) are pressed or stamped around the side surfaces <NUM> of the base <NUM> of the major terminal <NUM>. For example, after extending the post <NUM> through the opening <NUM> in the main body <NUM> of the major bus bar <NUM>, the assembly may be placed on a flat surface. A pressing mechanism or stamp may stamp the two flaps <NUM> downwardly from or proximate the top surface <NUM> of the base <NUM> around the side surfaces <NUM> of the base <NUM> of the major terminal <NUM>. In some embodiments, the flaps <NUM> may be heated before pressing the flaps in to place around the base <NUM> of the major terminal <NUM>. Heating the flaps <NUM> may enable movement of the flaps <NUM> without negatively affecting the major bus bar <NUM>.

The embodiment in <FIG> is only partially assembled, in accordance with certain embodiments. In some embodiments, the primary flap <NUM> is also folded around the base <NUM> to retain the base <NUM>. For example, <FIG> provide perspective views of embodiments of the major terminal <NUM> and the major bus bar <NUM> assembled for installation in the battery module <NUM> of <FIG>. For example, in the illustrated embodiments, the primary flap <NUM> of the three flaps <NUM> is folded or stamped around the side surface <NUM> of the base <NUM> and under the bottom surface <NUM> of the base <NUM> of the major terminal <NUM>. As previously described, the primary flap <NUM> may be heated before folding or stamping to enable the folding or stamping without negatively affecting the major bus bar <NUM>. Further, it should be noted that, in some embodiments, the two other flaps <NUM> (e.g., not the primary flap <NUM>) may be folded over at least a portion of the bottom surface <NUM> of the base <NUM> as well.

Focusing in particular on <FIG>, the base <NUM> includes, as previously described, the cylindrical portion <NUM> coupled to the post <NUM> and the rectangular portion <NUM> disposed around the post <NUM>. In some embodiments, the cylindrical portion <NUM> and the rectangular portion <NUM> may be aligned such that the bottom surface <NUM> is flush across the entirety of the base <NUM> (e.g., both the cylindrical and rectangular portions <NUM>, <NUM>). Further, in other embodiments, the base <NUM> may only include the rectangular portion <NUM>, as previously described. In the illustrated embodiment, the cylindrical portion <NUM> extends farther than the rectangular portion <NUM>, such that the bottom surface <NUM> is not flush across the cylindrical and rectangular portions <NUM>, <NUM>. In such configurations, as illustrated, the primary flap <NUM> may include a curved edge <NUM> surrounding a portion of an outer perimeter <NUM> of the cylindrical portion <NUM> of the base <NUM> of the major terminal <NUM>. However, in embodiments with only the rectangular portion <NUM>, the flaps <NUM> may not include the illustrated curved edge <NUM> (e.g., may include only substantially straight edges). Alternatively, in embodiments with only the rectangular portion <NUM>, an integrally formed cylindrical bump may extend from the bottom surface <NUM> of the rectangular portion <NUM>, where the curved edge <NUM> of the primary flap <NUM> interfaces with the integrally formed cylindrical bump.

In general, the rectangular portion <NUM> of the base <NUM> of the major terminal <NUM> is included to resist torque applied to the post <NUM> of the major terminal <NUM>, as previously described. For example, an electrical lead may couple to the post <NUM> and may enable power transmission from the post <NUM> to a load coupled to another end of the electrical lead, where the electrical lead may be clamped or screwed onto the post <NUM>, thereby applying torque to the post <NUM>. During coupling of the lead to the post <NUM>, torque may be applied. In accordance with an aspect of the illustrated embodiments, as the torque is applied to the post <NUM>, the post <NUM> transfers the torque to the rectangular portion <NUM> of the base <NUM> coupled to the post <NUM>, and the rectangular portion <NUM> contacts the major bus bar <NUM> at the flaps <NUM> wrapped around the rectangular portion <NUM> to resist turning of the base <NUM> (and, thus, turning of the major terminal <NUM>).

It should be noted that any one of the flaps <NUM> may wrap from a location proximate the top surface <NUM> of the base <NUM> to a location proximate the bottom surface <NUM> of the base <NUM>. For example, another embodiment of the assembled major terminal <NUM> and major bus bar <NUM> is shown in <FIG>, where the primary flap <NUM> only extends over the side surface <NUM> of the rectangular portion <NUM> of the base <NUM> and the two other flaps <NUM> extend over the bottom surface <NUM> of the base <NUM>. The two other flaps <NUM> wrapped around the bottom surface <NUM> of the base <NUM> each include curved edges <NUM> disposed proximate the outer perimeter <NUM> of the cylindrical portion <NUM> (or, in another embodiment, an integrally formed cylindrical bump of the rectangular portion <NUM>).

As previously described with reference to <FIG>, the electrical path <NUM> (e.g., having the major bus bar <NUM>) configured to establish electrical communication between the major terminal <NUM> of the battery module <NUM> and the minor terminal <NUM> of the electrochemical cell <NUM> may include additional or different components depending on, e.g., an orientation of the major terminal <NUM>. For example, a perspective view of an embodiment of the battery module <NUM> having major terminals <NUM> extending in direction <NUM> (e.g., as opposed to direction <NUM>, as shown in <FIG>) is shown in <FIG>. In the illustrated embodiment, the carrier <NUM> is installed on the housing <NUM> of the battery module <NUM>. Indeed, in some embodiments, the carrier <NUM> may be nested with the housing <NUM>, where the carrier <NUM> includes features configured to receive the minor bus bars <NUM> and the minor terminals <NUM> of the electrochemical cells <NUM>. In other embodiments, the carrier <NUM> may snap on to the housing <NUM> for case of installation, or the carrier <NUM> may be fastened, welded, adhesively coupled, or otherwise coupled to the housing <NUM>.

In the illustrated embodiment, and as noted above, the electrochemical cells <NUM> are coupled in series via the minor bus bars <NUM> extending between adjacent minor terminals <NUM> of the electrochemical cells <NUM>. The minor terminals <NUM> on either end of the aggregate network of interconnected electrochemical cells <NUM> are electrically coupled to the major terminals <NUM> via the electrical paths <NUM>, as previously described. However, because the major terminals <NUM> extend in direction <NUM> instead of direction <NUM> (e.g., along the same direction as the cell or minor terminals <NUM>), the electrical paths <NUM> in the embodiment in <FIG> may be different than the electrical paths <NUM> in the embodiment of <FIG>.

As one example of the difference between embodiments of <FIG> and <FIG>, the minor terminal <NUM> on either end of the aggregate network of interconnected electrochemical cells <NUM> is coupled to a connecting bar <NUM> that extends from the minor terminal <NUM> inwardly along the carrier <NUM> toward another component of the electrical path <NUM>. The connecting bar <NUM> may be considered a type of bus bar, but for clarity will be referred to herein as the connecting bar <NUM>. The connecting bar <NUM> may, for example, include a material corresponding to the material of the minor terminal <NUM> from which it extends (e.g., aluminum). In other words, the material of the connecting bar <NUM> may be the same material as the minor terminal <NUM>, or a material that, when welded to the minor terminal <NUM>, would not introduce substantial Galvanic effects. The connecting bar <NUM> is coupled to a bi-metal extension <NUM> that includes a first end <NUM> having a first material corresponding to the material of the connecting bar <NUM>, and a second end <NUM> opposite to the first end <NUM> and including a second material different than the first material. The second end <NUM>, for example, may be copper, and may couple to the bridge <NUM> (e.g., copper bridge). The bridge <NUM> may couple to the shunt <NUM>, which may be coupled to a printed circuit board (PCB <NUM>) as previously described. In the illustrated embodiment, another bridge <NUM> extends from the shunt <NUM> and couples to the major bus bar <NUM> wrapped around the major terminal <NUM>, as previously described. Thus, the illustrated electrical path <NUM> includes the connecting bar <NUM> extending from the minor terminal <NUM>, the bi-metal extension <NUM>, the bridge <NUM>, the shunt <NUM>, the other bridge <NUM>, and the major bus bar <NUM> coupled to the major terminal <NUM>. It should be noted that the two bridges <NUM> for each of the two electrical paths <NUM> (e.g., on either end of the battery module <NUM>) may be interchangeable and may also be symmetrical, such that the bridges <NUM> may be inserted into the electrical path <NUM> without having to substantially maneuver the bridges <NUM> to be oriented in a particular direction. In other words, the bridges <NUM> can be flipped over and rotated <NUM> degrees and would establish the connection between the shunt <NUM> and the bi-metal extension <NUM> in the same manner as shown.

To further illustrate these aspects of the present disclosure, a cut away perspective view of an embodiment of the battery module <NUM> taken along line <NUM>-<NUM> in <FIG> is shown in <FIG>. As previously described, the connecting bar <NUM> couples to the minor terminal <NUM> and to the bi-metal extension <NUM>. The connecting bar <NUM> may include an opening <NUM> configured to receive the minor terminal <NUM>, or the connecting bar <NUM> may press against a top surface of the minor terminal <NUM> or a top surface of a conductive component (e.g., a ring) surrounding the minor terminal <NUM>. The connecting bar <NUM> also contacts the first end <NUM> of the bi-metal extension <NUM> (e.g., where the connecting bar <NUM> and the first end <NUM> include the same material). The second end <NUM> of the bi-metal extension <NUM> may include a different material (e.g., copper) corresponding to the bridge <NUM> to which the second end <NUM> is coupled (e.g., welded). The bridge <NUM> couples to the shunt <NUM> (e.g., via a weld), the shunt <NUM> couples to the other bridge <NUM> (e.g., via a weld), and the other bridge <NUM> couples to the major bus bar <NUM> (e.g., via a weld) extending from the major terminal <NUM>. The major bus bar <NUM> may include an additional <NUM> degree bend (e.g., in the main body <NUM> of the major bus bar <NUM> shown in <FIG>) to couple the major bus bar <NUM> to the other bridge <NUM> (e.g., via a weld).

It should be noted that, as previously described, the major bus bar <NUM> includes one or more flaps, extensions, or members wrapped around the major terminal <NUM> (e.g., a base thereof) to retain the major terminal <NUM>. In accordance with an aspect of the present disclosure, the major terminal <NUM> need not be welded to the major bus bar <NUM>. Thus, dissimilar materials may be used for the major terminal <NUM> and the major bus bar <NUM> (e.g., stainless steel and copper, respectively). For example, as previously described, the major bus bar <NUM> may include copper (corresponding to the shunt <NUM>) and the major terminal <NUM> may include stainless steel (which may be cheaper and may be more readily manufactured than a copper terminal). In general, the above described electrical path <NUM> includes the particular components and locations of material transition(s) (e.g., from aluminum to copper) for ease of manufacturing. However, in other embodiments, the electrical path <NUM> may include fewer or more components, or differently shaped components, to accommodate other components and considerations in producing the battery module <NUM>, while still providing electrical communication between the major bus bar <NUM> and the major terminal <NUM> without welding the major bus bar <NUM> and the major terminal <NUM> together.

For example, an embodiment of a portion of the electrical path <NUM> having the major terminal <NUM> and the major bus bar <NUM> is shown in a perspective view in <FIG>. In the illustrated embodiment, the major terminal <NUM> includes only the rectangular portion <NUM> (e.g., without the cylindrical portion72) of the base <NUM>. It should be noted that the rectangular portion <NUM> may be substantially rectangular, but with slightly curved edges (e.g., as shown in the illustrated embodiment). Further, the major bus bar <NUM> includes only the primary flap <NUM> (e.g., of the flaps <NUM>), where the primary flap <NUM> is wrapped around the side surface <NUM> of the base <NUM> and under the bottom surface <NUM> of the base <NUM>. Thus, in the illustrated embodiment, the pocket <NUM> that retains the base <NUM> is formed by the primary flap <NUM> and the main body <NUM> above the primary flap <NUM>. As previously described, the primary flap <NUM> of the major bus bar <NUM> blocks rotation of the base <NUM> and, thus, of the major terminal <NUM> extending through the major bus bar <NUM>.

In the illustrated embodiment, the major bus bar <NUM> includes a curved portion <NUM> extending from the main body <NUM> and an extension <NUM> extending from the curved portion <NUM>. The curved portion <NUM> may include one or more curves (e.g., bends) to facilitate coupling of the major bus bar <NUM> to a component that may be oriented differently than the major bus bar <NUM>. For example, the curved portion <NUM> may enable coupling of the extension <NUM> to a component having a face (e.g., surface, side, substrate) that is oriented parallel to the extension <NUM>. In the illustrated embodiment, the curved portion <NUM> enables an angle <NUM> of approximately <NUM> degrees between the main body <NUM> of the major bus bar <NUM> and the extension <NUM> of the major bus bar <NUM>. However, it should be noted that the curved portion <NUM> may be configured to enable any suitable angle between the main body <NUM> and the extension <NUM> to facilitate suitable coupling of the extension <NUM> to another component of the electrical path <NUM>.

For example, perspective views of embodiments of the battery module <NUM> having the electrical path <NUM> including the major bus bar <NUM> and the major terminal <NUM> are shown in <FIG> and <FIG>. Focusing on <FIG>, the major bus bar <NUM> includes the main body <NUM>, the curved portion <NUM>, and the extension <NUM> extending from the curved portion <NUM>. As shown, the curved portion <NUM> enables approximately the <NUM> degree angle <NUM>, although, in another embodiment, the angle <NUM> may be more or less than <NUM> degrees. The curved portion enables coupling of the major bus bar <NUM> directly to the bridge <NUM> of the battery module <NUM>. Thus, in the illustrated embodiment, the electrical path <NUM> includes at least the major terminal <NUM>, the major bus bar <NUM> coupled to the major terminal <NUM>, the bridge <NUM> coupled to the extension <NUM> of the major bus bar <NUM>, the shunt <NUM>, and the other bridge <NUM> coupled to the shunt <NUM>. The electrical path <NUM> may also include other components such that the electrical path <NUM> extends from the major terminal <NUM> to one of the minor terminals (not shown) of one of the electrochemical cells (not shown) disposed in the battery module <NUM>.

Focusing on <FIG>, the major bus bar <NUM> includes the main body <NUM>, the curved portion <NUM>, and the extension <NUM> extending from the curved portion <NUM>. However, in the illustrated embodiment, the curved portion <NUM> enables a different angle <NUM> between the extension <NUM> and the main body <NUM> of the major bus bar <NUM>. For example, the angle <NUM> may be approximately <NUM> degrees. However, in other embodiments, the angle <NUM> may be <NUM>-<NUM> degrees, <NUM>-<NUM> degrees, <NUM>-<NUM> degrees, or <NUM>-<NUM> degrees. The curved portion <NUM> generally enables the angle <NUM> such that the extension <NUM> couples to a component <NUM> (e.g., bridge, bus, bus bar, connecting bar, contact, shunt) of the electrical path <NUM> that is substantially parallel to the extension <NUM>. However, in certain embodiments, the component <NUM> may not be substantially parallel to the extension <NUM>, but the curved portion <NUM> may enable the angle <NUM> to facilitate positioning of the extension <NUM> proximate to the component <NUM>. It should be noted that the curved portion <NUM>, and any other portion of the major bus bar <NUM> (e.g., the flaps <NUM>, the primary flap <NUM>, the extension <NUM>), may be manufactured by stamping the major bus bar <NUM>, heating and bending the major bus bar <NUM>, deep drawing the major bus bar <NUM> (e.g., via a cold formed process), a combination thereof, or any other suitable manufacturing means.

Turning now to <FIG>, a process flow diagram of a method <NUM> of assembling the electrical path <NUM> is shown. The method <NUM> includes providing the electrochemical cell <NUM> having the first terminal <NUM> (block <NUM>). For example, the electrochemical cell <NUM> may be a top or bottom cell in the stack <NUM> of electrochemical cells <NUM>, as previously described. The electrochemical cells <NUM> in the stack <NUM> may be electrically interconnected to generate a charge for powering a load. Thus, the charge generated by the stack <NUM> of electrochemical cells <NUM> travels to and through the first terminal <NUM> described above.

The method <NUM> also includes coupling the minor bus bar <NUM> or the connecting bar <NUM> to the first terminal <NUM> (block <NUM>). Depending on the particular configuration of the battery module <NUM>, the minor bus bar <NUM> may be a bi-metal bus bar for transitioning from a first material corresponding to the material of the first terminal <NUM> to a second material different from the first material. Alternatively, the connecting bar <NUM> may include only one material corresponding to the material of the first terminal <NUM>.

The method <NUM> further includes coupling (e.g., welding) the minor bus bar <NUM> or the connecting bar <NUM> to the bridge <NUM> or to an intervening component (e.g., a bi-metal extension <NUM>) (block <NUM>). For example, if the minor bus bar <NUM> is a bi-metal bus bar, the minor bus bar <NUM> may connect directly to the bridge <NUM>. If the connecting bar <NUM> is used, the bi-metal extension <NUM> may be included to transition to a different material corresponding to the material of the bridge <NUM> (e.g. copper). The bridge <NUM> may then be coupled with the bi-metal extension <NUM>.

Further, the method <NUM> includes coupling (e.g., welding) the bridge <NUM> to a shunt <NUM> (block <NUM>). The shunt <NUM> generally includes a material that enables voltage and/or temperature sensing at the shunt <NUM> (e.g., copper). Thus, the previously described material transition (e.g., from aluminum to copper) facilitates the use of copper for the shunt <NUM>.

Further still, the method <NUM> includes coupling (e.g., welding) the shunt <NUM> to another bridge <NUM> (block <NUM>). It should be noted that step <NUM> may not be utilized in certain embodiments. For example, in certain embodiments, the shunt <NUM> may be sandwiched between one bridge <NUM> and the major bus bar <NUM> of the battery module <NUM>, thereby rendering an additional bridge <NUM> unnecessary. However, in the illustrated method <NUM>, the first bridge <NUM> is coupled to the shunt <NUM>, and the shunt <NUM> is coupled to the second bridge <NUM>.

The method <NUM> also includes coupling (e.g., welding) the bridge <NUM> (e.g., the second bridge <NUM>) to the major bus bar <NUM>, as previously described (block <NUM>). The method <NUM> also includes folding, stamping, or otherwise maneuvering flaps <NUM> or extensions of the major bus bar <NUM> around the base <NUM> of the major terminal <NUM> of the battery module <NUM> (block <NUM>). The flaps <NUM> may be folded around the base <NUM> by heating and bending the flaps <NUM>, or via a cold formed process (e.g., deep drawing).

Further still, the method <NUM> includes embedding a lower portion of the base <NUM> of the major terminal <NUM>, of the major bus bar <NUM>, or of both, in a wall of the plastic housing <NUM> of the battery module <NUM>. As previously described, the lower portion may be embedded in the housing <NUM> such that the post <NUM> of the major terminal <NUM> extends vertically, horizontally, or otherwise, with respect to, e.g., the stacks <NUM> of the electrochemical cells <NUM>.

One or more of the disclosed embodiments, alone or in combination, may provide one or more technical effects useful in the manufacture of battery modules, and portions of battery modules. In general, embodiments of the present disclosure include a battery module with a major terminal and major bus bar coupled together without welding, e.g., by folding or stamping flaps or extensions of the major bus bar around a base of the major terminal. Retaining the major terminal by folding the flaps or extensions of the major bus bar around a base of the major terminal, as opposed to welding the two components together, enables dissimilar materials to be used for the major bus bar and the major terminal, thereby reducing a material cost of the battery module. Further, utilizing dissimilar materials may enable embedding of the major bus bar, the major terminal, of portions of both within a housing of the battery module, thereby reducing a volume devoted to the major bus bar and the major terminal such that an energy density of the battery module is increased. The technical effects and technical problems in the specification are exemplary and are not limiting. It should be noted that the embodiments described in the specification may have other technical effects and can solve other technical problems.

Claim 1:
A battery module (<NUM>, <NUM>), comprising:
- an electrochemical cell (<NUM>) having a minor terminal (<NUM>);
- a major terminal (<NUM>) electrically coupled to the electrochemical cell (<NUM>), wherein the major terminal (<NUM>) comprises a base (<NUM>) and a post (<NUM>) extending from the base (<NUM>); and
- an electrical path (<NUM>) between the minor terminal (<NUM>) of the electrochemical cell (<NUM>) and the major terminal (<NUM>) of the battery module (<NUM>, <NUM>), wherein the electrical path (<NUM>) comprises a bus bar (<NUM>), wherein the bus bar (<NUM>) comprises a main body (<NUM>) having an opening (<NUM>) disposed through the main body (<NUM>), wherein the post (<NUM>) extends through the opening (<NUM>), wherein the bus bar (<NUM>) comprises a first flap (<NUM>) having a folded and/or stamped end, and extending from the main body (<NUM>) of the bus bar (<NUM>), wherein the first flap (<NUM>) is wrapped around a first side surface (<NUM>) of the base (<NUM>) of the major terminal (<NUM>) such that the main body (<NUM>) and the first flap (<NUM>) at least partially define a pocket (<NUM>) that retains the base (<NUM>) of the major terminal (<NUM>) to block rotation of the base (<NUM>) of the major terminal (<NUM>).