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 battery module components that are used in xEVs. For instance, battery modules include one or more battery cells that generate thermal energy (e.g., heat), which may increase a temperature within a housing of the battery module. Existing battery modules may include various features that transfer thermal energy from within the battery module to a heat sink and/or a surrounding environment of the battery module. Unfortunately, existing features may be inefficient at removing thermal energy from the battery module and/or may be expensive and complex to incorporate into the battery module. The present disclosure is generally related to features that improve heat dissipation from within a battery module housing.

<CIT> and <CIT> disclose different battery packs.

The present invention is defined in independent claims <NUM> and <NUM> respectively.

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).

Based on the advantages over traditional gas-power vehicles, manufacturers, which generally produce traditional gas-powered vehicles, may desire to utilize improved vehicle technologies (e.g., regenerative braking technology) within their vehicle lines. Often, these manufacturers may utilize one of their traditional vehicle platforms as a starting point. Accordingly, since traditional gas-powered vehicles are designed to utilize <NUM> volt battery systems, a <NUM> volt lithium ion battery may be used to supplement a <NUM> volt lead-acid battery. More specifically, the <NUM> volt lithium ion battery may be used to more efficiently capture electrical energy generated during regenerative braking and subsequently supply electrical energy to power the vehicle's electrical system.

As advancements occur with vehicle technologies, high voltage electrical devices requiring voltage higher than <NUM> volts may also be included in the vehicle's electrical system. For example, the lithium ion battery may supply electrical energy to an electric motor in a mild-hybrid vehicle. Often, these higher voltage electrical devices utilize voltage greater than <NUM> volts, for example, up to <NUM> volts. Accordingly, in some embodiments, the output voltage of a <NUM> volt lithium ion battery may be boosted using a DC-DC converter to supply power to the high voltage devices. Additionally or alternatively, a <NUM> volt lithium ion battery may be used to supplement a <NUM> volt lead-acid battery. More specifically, the <NUM> volt lithium ion battery may be used to more efficiently capture electrical energy generated during regenerative braking and subsequently supply electrical energy to power the high voltage devices.

Thus, the design choice regarding whether to utilize a <NUM> volt lithium ion battery or a <NUM> volt lithium ion battery may depend directly on the electrical devices included in a particular vehicle. Nevertheless, although the voltage characteristics may differ, the operational principles of a <NUM> volt lithium ion battery and a <NUM> volt lithium ion battery are generally similar. More specifically, as described above, both may be used to capture electrical energy during regenerative braking and subsequently supply electrical energy to power electrical devices in the vehicle.

Accordingly, to simplify the following discussion, the present techniques will be described in relation to a battery system with a <NUM> volt lithium ion battery and a <NUM> volt lead-acid battery. However, one of ordinary skill in art is able to adapt the present techniques to other battery systems, such as a battery system with a <NUM> volt lithium ion battery and a <NUM> volt lead-acid battery.

The present disclosure relates to batteries and battery modules. More specifically, the present disclosure relates to features of a battery module housing that are configured to improve dissipation of thermal energy (e.g., heat) generated by one or more battery cells positioned within the battery module housing. Particular embodiments are directed to lithium ion battery modules that may be used in vehicular contexts (e.g., hybrid electric vehicles) as well as other energy storage/expending applications (e.g., energy storage for an electrical grid).

With the preceding in mind, the present disclosure describes improved features of a battery module housing that increase dissipation of thermal energy (e.g., heat) from within the battery module housing. As set forth above, one or more battery cells disposed within the battery module housing generate thermal energy as a result or byproduct of chemical reactions that ultimately create electrical energy, which may be supplied to, or consumed by, a load (e.g., a vehicle). The thermal energy increases a temperature within the battery module housing. In some cases, the increased temperature may affect operation of various components (e.g., the battery cells and/or electrical components) within the housing. Embodiments of the present disclosure are related to features of a battery module housing that enhance the dissipation of thermal energy generated within the battery module housing. Specifically, embodiments of the present disclosure are directed to a grid of fins that increase an amount of thermal dissipation through natural convection (e.g., passive transfer of thermal energy). In some embodiments, the fins may include channels or grooves that facilitate a flow of air between openings formed by the fins and/or between the fins and a surrounding environment. Further, the fins may contact a heat sink (e.g., a steel plate, a thermally conductive metal, aluminum, copper, a chassis of a vehicle) that absorbs thermal energy from the fins and further enhances thermal energy dissipation. In some embodiments, the heat sink may include a thermally conductive metal, such as aluminum or copper, that is positioned proximate to, or coupled to, a portion of the battery module housing having the fins. The heat sink may include a shape that conforms to a cross-sectional shape of the battery module housing, which may include a rectangular shape, a triangular shape, a hexagonal shape, or any other suitable shape.

The grid of fins is configured to balance an amount of surface area contacting the heat sink, a stiffness of the fins for supporting the battery module housing, and/or an amount of features for facilitating air flow between the openings formed by the fins and/or between the fins and the surrounding environment. In some embodiments, the grid of fins is integral with the battery module housing, thereby facilitating assembly of the battery module and reducing costs. In any case, the grid of fins increases thermal energy dissipation from within the battery module housing, thereby increasing an efficiency of the battery module.

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>, a display <NUM> within the vehicle, and the ignition system <NUM>, which may be used to start (e.g., crank) an 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 lead acid (e.g., a first) battery module <NUM> in accordance with present embodiments, and a lithium ion (e.g., a second) battery module <NUM>, where each battery module <NUM>, <NUM> includes one or more battery cells. In other embodiments, the energy storage component <NUM> may include any number of battery modules. Additionally, although the first battery module <NUM> and the second battery module <NUM> are depicted adjacent to one another, they may be positioned in different areas around the vehicle. For example, the second battery module <NUM> may be positioned in or about the interior of the vehicle <NUM> while the first 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, the first battery module <NUM> may utilize a lead-acid battery chemistry and the second battery module <NUM> may utilize a lithium ion battery chemistry. In such an embodiment, the 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>, determine a predicted temperature trajectory of either battery module <NUM> and <NUM>, determine predicted life span of either battery module <NUM> or <NUM>, determine fuel economy contribution by either battery module <NUM> or <NUM>, determine an effective resistance of each battery module <NUM> or <NUM>, control magnitude of voltage or current output by the alternator <NUM> and/or the electric motor <NUM>, and the like.

Accordingly, the control module (e.g., unit) <NUM> may include one or more processors <NUM> and one or more memories <NUM>. More specifically, the one or more processors <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. Generally, the processor <NUM> may perform computer-readable instructions related to the processes described herein. Additionally, the processor <NUM> may be a fixed-point processor or a floating-point processor.

Additionally, the one or more memories <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 module <NUM> may include portions of a vehicle control unit (VCU) and/or a separate battery control module. Additionally, as depicted, the control module <NUM> may be included separate from the energy storage component <NUM>, such as a standalone module. In other embodiments, the battery management system (BMS) may be included within the energy storage component <NUM>.

In certain embodiments, the control module <NUM> or the processor <NUM> may receive data from various sensors <NUM> disposed within and/or around the energy storage component <NUM>. The sensors <NUM> may include a variety of sensors for measuring current, voltage, temperature, and the like regarding the battery module <NUM> or <NUM>. After receiving data from the sensors <NUM>, the processor <NUM> may convert raw data into estimations of parameters of the battery modules <NUM> and <NUM>. As such, the processor <NUM> may render the raw data into data that may provide an operator of the vehicle <NUM> with valuable information pertaining to operations of the battery system <NUM>, and the information pertaining to the operations of the battery system <NUM> may be displayed on the display <NUM>. The display <NUM> may display various images generated by device <NUM>, such as a GUI for an operating system or image data (including still images and video data). The display <NUM> may be any suitable type of display, such as a liquid crystal display (LCD), plasma display, or an organic light emitting diode (OLED) display, for example. Additionally, the display <NUM> may include a touch-sensitive element that may provide inputs to the adjust parameters of the control module <NUM> or data processed by the processor <NUM>.

The energy storage component <NUM> may have dimensions comparable to those of a typical lead-acid battery to limit modifications to the vehicle <NUM> design to accommodate the battery system <NUM>. For example, the energy storage component <NUM> may be of similar dimensions to an H6 battery, which may be approximately <NUM>,<NUM> x <NUM>,<NUM> x <NUM>,<NUM> (<NUM> inches x <NUM> inches x <NUM> inches) As depicted, the energy storage component <NUM> may be included within a single continuous housing. In other embodiments, the energy storage component <NUM> may include multiple housings coupled together (e.g., a first housing including the first battery <NUM> and a second housing including the second battery <NUM>). In still other embodiments, as mentioned above, the energy storage component <NUM> may include the first battery module <NUM> located under the hood of the vehicle <NUM>, and the second battery module <NUM> may be located within the interior of the vehicle <NUM>.

<FIG> is a perspective view of an embodiment of the battery <NUM> that includes a first battery module terminal <NUM> and a second battery module terminal <NUM>. The battery module terminals <NUM>, <NUM> are disposed on a battery module housing <NUM> and are electrically coupled to one or more battery cells disposed within a cavity of the housing <NUM>. As such, a load or a power supply may be coupled to the battery module terminals <NUM>, <NUM>, such that the battery <NUM> supplies and/or receives electrical power. As shown in the illustrated embodiment of <FIG>, the cavity of the housing <NUM> is sealed via a cover <NUM>. In some embodiments, the cover <NUM> is secured to the housing <NUM> via a weld (e.g., a laser weld), fasteners, another suitable technique, or a combination thereof. In any case, the cavity of the housing is substantially sealed (e.g., air-tight or water-tight) to block gases or fluids within the housing from leaking into an environment <NUM> surrounding the battery <NUM> and/or to block water or other contaminants from entering into the housing from the environment <NUM> surrounding the battery <NUM>. In some embodiments, the battery module housing <NUM> and/or the cover <NUM> may include a polymeric material, such as polypropylene, nylon, or another suitable material. Additionally, the polymeric material of the battery module housing <NUM> and/or the cover <NUM> may include an additive, such as a glass fiber additive. However, in other embodiments, the battery module housing <NUM> and/or the cover <NUM> may include any suitable material.

As discussed above, one or more battery cells disposed within the cavity of the housing <NUM> generate thermal energy to produce electrical energy, which is ultimately supplied to a load via the battery module terminals <NUM>, <NUM>. Embodiments of the present disclosure are directed to an improved thermal energy management system <NUM> that increases an amount of thermal energy dissipation from within the battery module housing <NUM>. For example, <FIG> is a perspective view of an embodiment of the thermal energy management system <NUM>. As shown in the illustrated embodiment of <FIG>, the thermal energy management system <NUM> includes a plurality of fins <NUM> forming a grid-like structure on a portion <NUM> (e.g., bottom surface) of the battery module housing <NUM>. For example, the plurality of fins <NUM> include projections from the portion <NUM> of the housing <NUM>. The plurality of fins <NUM> form openings <NUM> that are configured to receive and/or otherwise enclose pockets of air. In some embodiments, the openings <NUM> receive air <NUM> from the environment <NUM> (e.g., outside air) surrounding the battery <NUM>, which may flow through channels or openings <NUM> formed in the portion <NUM> of the battery module housing <NUM> and absorb thermal energy from the fins <NUM>. Additionally or alternatively, a fan or other suitable device may be utilized to direct air from the environment <NUM> across the plurality of fins <NUM> and/or between the openings <NUM>. In other embodiments, the plurality of fins <NUM> may be isolated from the environment <NUM>. In such embodiments, air present within the openings <NUM> may flow across the plurality of fins <NUM> to adjacent openings <NUM>, thereby distributing thermal energy substantially evenly between the each of the openings <NUM>.

In some embodiments, the plurality of fins <NUM> is integrally formed with the battery module housing <NUM>. For example, the battery module housing <NUM>, and thus the plurality of fins <NUM>, may be formed via an injection molding technique. Integrally forming the plurality of fins <NUM> with the battery module housing <NUM> reduces manufacturing costs by eliminating an additional component that is included to dissipate heat from within the battery module housing <NUM>. Accordingly, the plurality of fins <NUM> and/or the portion <NUM> of the battery module housing <NUM> may include the same material as the battery module housing <NUM>, such as polypropylene, nylon, or another suitable material. Further as set forth above, the battery module housing <NUM>, and thus the plurality of fins <NUM> and/or the portion <NUM>, may include an additive within the polypropylene, nylon, or another suitable material, such as a glass fiber additive.

In some embodiments, the plurality of fins <NUM> include a plurality of channels <NUM> (e.g., grooves) that are formed within at least a portion <NUM> of one or more fins <NUM> of the plurality of fins <NUM>. As shown in the illustrated embodiment of <FIG>, the channels <NUM> are formed on portions <NUM> of the plurality of fins <NUM> extending along an axis <NUM>. Additionally, portions <NUM> of the plurality of fins <NUM> extending along an axis <NUM>, crosswise to axis <NUM>, may also include the channels <NUM>. In other embodiments, the portions <NUM> of the plurality of fins <NUM> may not include the channels <NUM> and/or the portions <NUM> may not include the channels <NUM>. The number of channels <NUM> included within the plurality of fins <NUM> may be based on a desired stiffness of the plurality of fins <NUM>. For example, forming a large number of the channels <NUM> within the plurality of fins <NUM> may reduce the stiffness of the plurality of fins <NUM>, which may compromise the structural integrity of the battery module housing <NUM>. Accordingly, the number of channels <NUM> may be determined based on a stiffness of the plurality of fins <NUM> to maintain the structural integrity of the battery module housing <NUM>.

As shown, the channels <NUM> extend across a length <NUM> of the portions <NUM> and extend a depth <NUM> into the portions <NUM>. In some embodiments, the depth <NUM> of the channels <NUM> is between <NUM> millimeters (mm) and <NUM>, between <NUM> and <NUM>, or between <NUM> and <NUM>. In any case, the channels <NUM> are configured to facilitate a flow of air across each of the plurality of fins <NUM>. As such, thermal energy within a center <NUM> of the portion <NUM> of the housing <NUM> may be absorbed by ambient air and dissipated into the environment <NUM> surrounding the battery <NUM> and/or transferred to openings <NUM> further away from the center <NUM> of the portion <NUM> of the housing <NUM>.

In some embodiments, the battery module housing <NUM> may further include one or more projections <NUM> that extend from the portion <NUM> and into the openings <NUM>. The projections <NUM> may increase an amount of surface area exposed to air, thereby increasing an amount of thermal energy dissipated from within the housing <NUM>. As shown in the illustrated embodiment of <FIG>, the projections <NUM> may include a substantially cylindrical shape. However, in other embodiments, the projections <NUM> may include other suitable polygonal shapes that increase a surface area of the thermal management system <NUM> exposed to air. Additionally or alternatively, the projections <NUM> may include a length that is less than a length of the plurality of fins <NUM>. As such, the projections <NUM> do not block a flow of air across the grid (e.g., between openings <NUM>) formed by the plurality of fins <NUM>, thereby enabling an increased amount thermal energy transfer. In other embodiments, the projections <NUM> may include substantially the same (e.g., within <NUM>% of, within <NUM>% of, within <NUM>% of) length as the plurality of fins <NUM>. In still further embodiments, the projections <NUM> may include another suitable length.

While the illustrated embodiment of <FIG> shows the plurality of fins <NUM> having a substantially square shape (e.g., cross-sectional shape), it should be recognized that the plurality of fins <NUM> may include other suitable shapes (e.g., cross-sectional shapes). For instance, <FIG> is a perspective view of an embodiment of the battery having the thermal management system <NUM> with cylindrical shaped fins <NUM> (e.g., circular cross-sectional shape). In still further embodiments, the plurality of fins <NUM> may include a cross-sectional shape that is circular, triangular, rectangular, square, pentagonal, hexagonal, heptagonal, octagonal, nonagonal, another suitable polygonal shape, or a combination thereof.

<FIG> is a cross-section of the battery <NUM> having the thermal energy management system <NUM>. As shown in the illustrated embodiment of <FIG>, the plurality of fins <NUM> extend from a wall <NUM> (e.g., a pad or the portion <NUM>) positioned adjacent to a plurality of battery cells <NUM>. In some embodiments, the wall <NUM> may be integrally formed with the battery module housing <NUM> and include a thickness that is approximately (e.g., within <NUM>% of, within <NUM>% of, or within <NUM>% of) <NUM>. In any case, the wall <NUM> absorbs thermal energy generated by the plurality of battery cells <NUM> and ultimately transfers the thermal energy to the plurality of fins <NUM>. As discussed above, air may flow across the plurality of fins <NUM> and absorb thermal energy from the plurality of fins <NUM>. In some cases, the thermal energy is dissipated to the environment <NUM>, while in other cases, the thermal energy is distributed to adjacent openings <NUM> formed by the plurality of fins <NUM>. In some embodiments, the plurality of fins <NUM> may extend a distance <NUM> (e.g., a length) from the wall <NUM>. For example, the distance <NUM> may be between <NUM> millimeters (mm) and <NUM>, between <NUM> and <NUM>, or between <NUM> and <NUM>. In other embodiments, the distance <NUM> may be approximately (e.g., within <NUM>% of, within <NUM>% of, or within <NUM>% of) <NUM>.

Additionally, the plurality of fins <NUM> may include a thickness <NUM>. The thickness <NUM> of the plurality of fins <NUM> determines a surface area exposed to the ambient air as well as a surface area contacting a heat sink (see, e.g., <FIG>). As such, the plurality of fins <NUM> dissipate thermal energy from within the battery module housing <NUM> via ambient air and through the heat sink. The thickness <NUM> of the plurality of fins <NUM> may be determined by balancing the various surface areas (e.g., a first surface area exposed to ambient air and a second surface area contacting the heat sink) to achieve a threshold amount of thermal energy transfer. Such determination may be made through experimental testing, models of existing data, and/or other suitable techniques. Further, in some embodiments, the thickness <NUM> of the fins <NUM> may vary throughout the distance <NUM> from the wall <NUM>. For instance, the thickness <NUM> may taper from the wall <NUM> toward distal ends <NUM> of the plurality of fins <NUM>. In such embodiments, a greater amount of thermal energy may be absorbed from the wall <NUM> by the plurality of fins <NUM>, thereby increasing an amount of thermal energy dissipation achieved by the plurality of fins <NUM>. Additionally or alternatively, the thickness <NUM> of the plurality of fins <NUM> may be substantially equal along a cross-section of each fin of the plurality of fins <NUM>. In other words, sides of the fins <NUM> that form the cross-sectional shape of the fins <NUM> may include substantially the same thickness <NUM> at any point along the distance <NUM>.

As shown in the illustrated embodiment of <FIG>, the grid formed by the plurality of fins <NUM> may be substantially surrounded by a channel <NUM> formed around a perimeter of the portion <NUM> of the battery module housing <NUM>. In some embodiments, the channel <NUM> may receive ambient air from the environment <NUM> surrounding the battery <NUM> and enable the ambient air to be directed across the plurality of fins <NUM>, such that thermal energy from within the battery module housing <NUM> is absorbed and dissipated to the environment <NUM>. Additionally or alternatively, the channel <NUM> provide structural support to the battery module housing <NUM> by providing a buffer between the grid formed by the plurality of fins <NUM> and a perimeter of the battery module housing <NUM>.

<FIG> is a cross-section of an embodiment of the battery <NUM> having the thermal management system <NUM>. As shown in the illustrated embodiment of <FIG>, the battery module housing <NUM> is disposed on a heat sink <NUM> (e.g., a steel plate, a metallic sheet, a chassis of a vehicle, copper, aluminum, or another conductive material). As such, the plurality of fins <NUM> contact, or are otherwise adjacent to, the heat sink <NUM>. The heat sink <NUM> absorbs thermal energy from the plurality of fins <NUM> and/or the air flowing across the plurality of fins <NUM>. Accordingly, the thermal management system <NUM> enables thermal energy to be transferred to both the heat sink <NUM> and to air within the openings <NUM>, thereby increasing an amount of thermal energy dissipation and increasing an efficiency of the battery <NUM>.

Claim 1:
A battery system, comprising:
- a housing (<NUM>) configured to receive a battery cell (<NUM>), wherein the battery cell (<NUM>) is configured to output thermal energy as a byproduct of electrical energy generation and/or consumption;
- a wall (<NUM>) of the housing (<NUM>) with a first side positioned proximate to the battery cell (<NUM>); characterized by
- a plurality of fins (<NUM>) extending from a second side of the wall (<NUM>), wherein the plurality of fins (<NUM>) is configured to absorb thermal energy from the battery cell (<NUM>) and dissipate the thermal energy to air, or a heat sink (<NUM>), or both, and wherein a fin (<NUM>) of the plurality of fins (<NUM>) comprises a channel (<NUM>) configured to facilitate a flow of the air between the fin (<NUM>) of the plurality of fins (<NUM>) and an adjacent fin (<NUM>) of the plurality of fins (<NUM>).