Patent Description:
Many vehicles in operation today are powered, at least in part, by electrical systems. To provide sufficient electricity to power an entire vehicle, the electrical system typically includes batteries configured with multiple cells, each cell adding its voltage potential to a respective battery. Thus, an increase in a number of cells included in a battery directly results in an increase in an amount of power provided by the battery. However, the increase in the number of cells may additionally increase a risk of the battery overheating due to heat generated by a cell. <CIT> discloses a battery pack comprising: a battery module receiving a plurality of battery cells, and forming a first connector; a frame stacking the battery module; and an electric connection member provided to flow electricity, coupled to the frame, and having a second connector connected to the first connector. <CIT> discloses a rack-mount power supply device having a plurality of battery packs removably placed in a rack main body. In each battery pack, a battery including a plurality of unit cells is housed in an outer case, and positive and negative output terminals are provided so as to come out on a back surface of the outer case.

This disclosure is directed to techniques for improving thermal runaway mitigation for batteries, such as may be used in a vehicle electrical system. The vehicle described herein may include a vehicle that is powered in whole or in part by one or more batteries. Although primarily discussed in the context of powering an autonomous vehicle, the methods, apparatuses, and systems described herein may be applied to providing power to a variety of systems (e.g., a sensor system or a robotic platform), and are not limited to autonomous vehicles. In another example, the techniques may be utilized in an aviation or nautical context, as a distributed storage system, a battery backup system, or in any system powered by the one or more batteries.

A vehicle electrical system may include a plurality of batteries configured in one or more battery packs. In some examples, a battery pack may include batteries (e.g., battery modules, battery subsystems, etc.) configured substantially horizontally, such as in a side-by-side configuration. In at least one example, a battery pack may include multiple stacked batteries. The battery pack may include a casing configured to secure the batteries in place in the vehicle. The casing may be made of a metal material (e.g., aluminum, steel, titanium, etc.), a plastic material (e.g., polymer, etc.), a ceramic material, a composite material (e.g., fiberglass, carbon fiber, Kevlar, etc.), or a combination of the foregoing.

The battery pack may include multiple battery module bays, each battery module bay being configured to house a battery module. In various examples, each battery module bay may include a pair of rails configured on opposing sides of an interior surface of the casing. The pairs of rails may be configured to connect to couplers on opposing sides of a battery module (e.g., exterior surface of a battery housing). For example, a first coupler of a battery module may be configured to receive a first rail of a pair of rails and a second coupler of the battery module may be configured to receive a second rail of the pair of rails. To insert the battery into the battery pack (e.g., casing of the battery pack), the first coupler and the second coupler may slide along the first rail and the second rail, respectively. In some examples, each battery module bay may include a rail configured on an interior surface and a coupler on an opposing interior surface (e.g., opposite side wall). In such examples, a battery module may be configured with a rail disposed on one exterior side wall and a coupler disposed on an opposite exterior side wall. The couplers of the battery module and the casing may be configured to couple to the respective rails of the battery module and the casing. The battery may be secured into the casing via one or more fasteners (e.g., screws, rivets, pins, snap connectors, latches, spring-type fasteners, etc.) at an end of the rails.

In various examples, an insertion of the batteries into the battery pack may cause a stiffness of the battery pack to increase. The stiffness may influence a resonant (e.g., vibrational, modal, etc.) frequency of the battery pack, such as during vehicle operation. In some examples, after insertion of the batteries into the battery pack, the stiffness of the battery pack may be greater than a stiffness associated with the vehicle body and/or other components of the vehicle. In such examples, modal frequencies associated with the battery pack, the vehicle body, and/or components of the vehicle may substantially differ. For example, a modal frequency associated with the vehicle body may be <NUM> Hertz and a modal frequency associated with a battery pack with batteries inserted may be <NUM> Hertz. The difference between the stiffness of the vehicle and the stiffness of the battery pack (and consequent <NUM> Hertz difference in modal frequencies) may help prevent resonance and reduce vibration and noise experienced by a passenger in the vehicle.

In various examples, at least some of the battery module bays may include a space surrounding at least a portion of a battery module. The space may include an air gap between a top of a first module and a bottom side of a second module. The air gap may act as a barrier to heat transfer between the first and second modules. In some examples, the space may extend to a side portion of the respective battery module. The space may be bounded, at least in part, by the pairs of rails associated with the first and second modules (e.g., pairs of rails to which the first module and the second module are coupled). In various examples, the pairs of rails may be configured to substantially thermally insulate a first battery module bay from a second battery module bay. In such examples, the pairs of rails may provide a barrier configured to preclude hot gases produced by a battery module, such as in thermal runaway, from substantially affecting another battery module.

In various examples, the battery module may include a battery housing. The battery housing may include a cover, one or more sidewalls, and a base. The cover, the side wall(s), and/or the base may comprise a sheet of metal material, ceramic material, plastic material, composite material, or a combination thereof. Each of the cover, the side wall(s), and the base may be made of a same or different material from one another. In at least one example, the cover may comprise a sheet of stainless-steel material. In some examples, the cover, the side wall(s), and/or the base may include an insulating material (e.g., mica, silicone rubber, Teflon, etc.), which, when provided, may be laminated, glued, or otherwise affixed to the cover. In various examples, the cover, the side wall(s), and/or the base may be configured to substantially thermally insulate a respective battery module from another battery module situated adjacent (e.g., above or below) the respective battery module. In various examples, at least two of the side wall(s) of the battery housing may be configured with couplers configured to receive rails, such as those described above. In some examples, one side wall of the battery may be configured with a coupler to receive a rail, and an opposing side wall may be configured with a rail to couple to a coupler of the casing of the battery pack.

In various examples, the battery housing may enclose a plurality of cells. In various examples, the battery modules may be configured to vent gases, such as gases emitted from one or more of the plurality of cells. In such examples, the gases may vent out of the battery module via one or more battery module vents. In some examples, the gases may vent from an interior compartment of the battery module into the space surrounding at least the portion of the battery module. In various examples, each battery module bay of the battery pack may include one or more vents (e.g., casing vents) for venting gases outside of the casing. The casing vent(s) may be configured to substantially equalize pressure between the battery module bay (e.g., space containing gas) and an atmosphere outside the casing. In some examples, the casing vent(s) may comprise a breathable material (e.g., membrane) configured to filter contaminants from gases exiting the vent(s) and/or to prevent contaminants from entering the battery pack. In various examples, the casing vent(s) may be configured to be sealed during normal operation and to "blow out" (i.e., release pressure) such as when subjected to a threshold pressure differential between the battery module bay and the atmosphere outside the vehicle. The battery module vent(s) and the casing vent(s) may prevent a battery module from over-pressurizing and/or over-heating, such as in the case of a cell failure and/or thermal runaway.

In some examples, the plurality of cells may be configured in multiple rows of cells. In various examples, the cells in a row of cells may be in parallel. In some examples, the cells in a row of cells may be configured in series. In some examples, each cell in a roll of cells may be configured with a positive polarity on a first side of the battery module and a negative polarity on a second side of the battery module opposite the first side.

In various examples, the plurality of cells may be electrically coupled via one or more wires or bus bars. In various examples, a positive terminal associated with cells of a first row of cells may be connected to a bus bar situated between the first row of cells and a second row of cells. In such examples, a negative terminal associated with cells of the second row of cells may be connected to the bus bar. In various examples, the plurality of cells may be electrically coupled such that a most positive charge (e.g., positive terminal) is at a first end of a first side wall and a most negative charge (e.g., negative terminal) is at a second end of a second side wall, the first end and the second end being opposite ends of the side walls, and the first side wall and the second side wall being opposing side walls in the battery housing. In such examples, the positive terminal and the negative terminal of each battery module may be disposed at opposite corners. In various examples, the disposition of the positive terminal and the negative terminal at opposite corners of each battery module may substantially preclude a bridging event (e.g., arcing) between the two terminals, thereby enhancing safety of battery module use.

In various examples, the battery modules may be inserted into the battery pack (e.g., casing) such that every other battery module has a positive terminal and negative terminal aligned. For example, a first battery module may be inserted with a positive terminal situated at a left front corner of the battery pack and a second battery module adjacent to the first battery module may be inserted with a negative terminal situated at the left front corner of the battery pack. A third battery module adjacent to the second battery module may be inserted with a positive terminal situated at the left front corner of the battery pack, etc..

In various examples, the battery modules in a battery pack may be configured in series. In such examples, a positive terminal of a first battery module may be electrically coupled to a negative terminal of a second battery module, a positive terminal of the second battery module may be electrically coupled to a negative terminal of a third battery module, and so on. In at least one example, a first positive bus bar may carry a most positive charge from a last battery module (e.g., a bottom battery module in a stack) to a high voltage junction box (e.g., junction box)configured to monitor voltage and/or current provided by the battery pack and a first negative bus bar may carry a most negative charge of the battery pack from a first battery module (e.g., a top battery module in a stack) to the high voltage junction box. The high voltage junction box may additionally be configured to allow power to flow to a drive module of the vehicle (e.g., a drive module associated with the battery pack) to operate the vehicle.

In various examples, a second positive bus bar and a second negative bus bar may additionally be electrically coupled to the high voltage junction box associated with the battery pack at a first end and a connector at a second end. The second positive bus bar and the second negative bus bar may include high-voltage bus bars. In some examples, the connector may include a floating connector. In such examples, the connector may be configured to accommodate relative misalignment of plugs, such as that caused by vibration and/or other movement of the vehicle. In various examples, the connector may be configured to transfer power provided by the battery modules to a battery balance box, such as via one or more cables, wires, bus bars, or other electrical couplings. Additionally, the connector may be configured to receive power from the battery balance box, such as that received from a second set of battery modules situated in a second battery pack (e.g., of a second drive module). The battery balance box may be configured to maximize the capacity of each battery pack by modulating the charge and/or discharge of batteries based on the capacity associated therewith. In various examples, the second positive bus bar and the second negative bus bar may be configured to carry power from the high voltage junction box associated with the battery pack and/or carry power from the high voltage junction box associated with the battery pack, such as when the battery balance box determines that an unequal amount of power between two or more battery packs of a vehicle.

In various examples, the second positive bus bar and/or the second negative bus bar may be configured to de-energize in the event of a thermal runaway or other failure or malfunction of a battery module associated with the battery pack. In some examples, the second positive bus bar and/or the second negative bus bar may de-energize based at least in part on a drop and/or surge in voltage provided to the high voltage junction box by the first positive bus bar and the first negative bus bar. In some examples, the second positive bus bar and/or the second negative bus bar may be de-energized based on a drop and/or surge in voltage exceeding a threshold voltage, such as that indicative of a thermal runaway and/or failure of a battery module. In various examples, the high voltage junction box may detect the drop and/or surge in voltage and may de-energize one or both of the respective second bus bars. In some examples, the battery balance box may detect the drop and/or surge in voltage and may de-energize one or both of the respective second bus bars. For example, a third battery in a battery pack including six batteries may short circuit due to a failure of one or more cells corresponding to the third battery. The voltage provided by the battery pack may consequently drop resulting in a total voltage provided to drive module being less than an expected voltage (e.g. less than a voltage required to run the components of the drive module, less than a threshold voltage). Based on the voltage drop, the drive module and/or balance box may sense a failure in the battery pack and de-energize the second positive and/or second negative bus bars.

<FIG> is an illustration of an autonomous vehicle <NUM> in which battery packs <NUM> configured with thermal runaway mitigation systems may provide power to operating systems of the autonomous vehicle, in accordance with embodiments of the disclosure. In the illustrative example, the vehicle <NUM> includes two battery packs <NUM>. In other examples, the vehicle <NUM> may include a greater or lesser number of battery packs <NUM>.

The battery packs <NUM> may be configured with one or more battery modules <NUM> (e.g., batteries, battery subsystems, etc.). In the illustrative example, the battery packs include six battery modules <NUM> configured in a stack. In other examples, the battery packs <NUM> may include a greater or lesser number of battery modules <NUM>. Additionally, in other examples, the battery module(s) <NUM> may be configured differently, such as substantially horizontally and/or substantially vertically, or in any other configuration.

In various examples, the battery module(s) <NUM> may be configured to provide power to a drive module <NUM> associated with the battery pack via a high voltage junction box <NUM>. The drive module <NUM> may be configured to control operation of the various vehicle systems. For example, the drive module <NUM> may control steering, wheel speed, and/or other components of the powertrain and/or drivetrain of the vehicle <NUM>, as well as HVAC, etc..

In various examples, the battery module(s) <NUM> may be securably coupled to a casing <NUM> of the battery pack <NUM>. The casing <NUM> may include a metal material (e.g., aluminum, steel, titanium, etc.), a plastic material (e.g., polymer, etc.), a ceramic material, a composite material (e.g., fiberglass, carbon fiber, Kevlar, etc.), or a combination of the foregoing. In at least one example, the casing <NUM> may include a metal material, formed via an extrusion process. In various examples, the casing may include a base, a cover, and four side walls including a front side wall, a rear side wall, a right side wall and a left side wall (e.g., first side wall, second side wall, third side wall, fourth side wall). Although illustrated as a cross section, with one side of the casing <NUM> removed, the casing <NUM> of the battery pack <NUM> is configured to envelope the battery modules <NUM> on all sides. In various examples, the casing <NUM> of the battery pack <NUM> may be configured to be substantially water proof and/or water resistant.

In various examples, each battery module <NUM> may be configured to couple to a casing attachment mechanism. In some examples, the casing attachment mechanism may include rails <NUM>. The rails <NUM> may include a metal material, a ceramic material, a composite material, a plastic material, or a combination of the foregoing. The rails <NUM> may include the same material or a different material as the casing <NUM>. In some examples, the rails may be disposed on an internal surface of the front side wall (e.g., first side wall) and the rear side wall (e.g., second side wall) in a substantially horizontal configuration. In some examples, the rails <NUM> may extend from a first end, substantially situated at the right side wall (e.g., third side wall), to a second end, substantially situated at the left side wall (e.g., fourth side wall). In such examples, the rails <NUM> may substantially extend a length of the casing <NUM>.

The rails <NUM> may be configured to connect to couplers on opposing sides of a battery module <NUM> (e.g., exterior surface of a battery housing). In various examples, the rails <NUM> may include a coating. The coating may include rubber, polyurethane, nylon, Teflon, silicone, polypropylene, polyethylene, or the like. In some examples, the coating may be configured to increase and/or decrease a frictional component between the rails <NUM> and the couplers of the battery modules <NUM>. In some examples, the coating may be configured to assist in substantially thermally isolating heat one battery module from affecting another battery module <NUM>. In such examples, the coating may assist in preventing gases, such as those emitted from a battery module <NUM> during thermal runaway, from passing through the coupler between the battery module <NUM> and the rails <NUM>.

In the illustrative example, the rails <NUM> (e.g., casing attachment mechanisms, casing couplers, etc.) are configured in pairs of rails <NUM> disposed on opposite internal surfaces of the battery pack <NUM>, each of the pairs of rails <NUM> connected to couplers (e.g., module couplers, module attachment mechanisms, etc.) on opposite sides of a battery module <NUM>. In some examples, the casing attachment mechanism may include a casing coupler disposed on an internal surface opposite a rail <NUM>. In such examples, a battery module <NUM> may be configured to couple to a casing coupler via a rail disposed on the battery module <NUM> on one side and a rail <NUM> of the battery pack <NUM> via a module coupler on the other side. In some examples, the opposing internal surfaces of the battery pack <NUM> may include alternating rails <NUM> and casing couplers. For example, a casing coupler may be disposed between two rails. In some examples, the opposing internal surfaces of the battery pack <NUM> may include casing couplers on a first internal surface and rails <NUM> on a second internal surface, the first internal surface and the second internal surface being opposite internal side walls.

In various examples, each rail <NUM> may be disposed at a substantially equal distance vertically from one another. In such examples, each battery module <NUM> may be spaced a substantially similar vertical distance from another battery module <NUM> inserted into the casing <NUM>. For example, after insertion, such as via sliding the couplers of the battery module <NUM> along the rails <NUM>, a bottom side of a first battery module <NUM>(<NUM>) may be spaced a distance from a top side (e.g., cover) of a second battery module <NUM>(<NUM>). The distance may provide an air gap configured to prevent direct thermal conduction between the first battery module <NUM>(<NUM>) and the second battery module <NUM>(<NUM>).

Additionally, after insertion, the battery module(s) <NUM> may be secured into the casing via one or more fasteners (e.g., screws, rivets, pins, snap connectors, latches, spring-type fasteners, etc.) at an end of the rails. In some examples, as will be discussed in more detail below with regard to <FIG>, a battery module <NUM> may be secured into the casing <NUM> with a plate coupling to the battery module <NUM> and the end of each rail of a pair of rails <NUM>. In such examples, each battery module <NUM> may be configured to be removed and replaced independently, such as by removing the respective fasteners and plates.

In various examples, an insertion of the battery module(s) <NUM> into the battery pack <NUM> may cause a stiffness of the battery pack <NUM> to increase. The stiffness may correspond to a vibrational frequency of the battery pack <NUM>, such as during vehicle operation. In some examples, after insertion of the battery module(s) <NUM> into the battery pack <NUM>, the vibrational frequency (e.g., modal frequency) of the battery pack may increase to a threshold amount (e.g., <NUM> Hertz, <NUM> Hertz, etc.) greater than a vibrational frequency associated with the vehicle body <NUM> and/or other components of the vehicle <NUM>. In such examples, vibrational frequencies associated with the battery pack <NUM>, the vehicle body <NUM>, and/or components of the vehicle <NUM> may substantially differ. For example, a vibrational frequency associated with the vehicle body <NUM> may be <NUM> Hertz and a vibrational frequency associated with a battery pack <NUM> with battery module(s) <NUM> inserted may be <NUM> Hertz. The difference between the vibrational frequency of the vehicle body <NUM> and the vibrational frequency of the battery pack <NUM> (e.g., <NUM> difference between the two) may substantially prevent the vehicle body <NUM> and the battery pack <NUM> from vibrating at a same or similar frequency, causing an audible noise to a passenger in the vehicle.

In various examples, the stiffness of the battery pack <NUM> may correspond to a strength of the battery pack <NUM>, such as in a crash scenario. In such examples, the increased stiffness resulting from inserted battery modules being securably coupled to the casing <NUM> may provide an additional safety feature for a passenger in the case of a collision with another object (e.g., another vehicle, etc.). In some examples, after insertion of the battery module(s) <NUM> into the battery pack <NUM>, the stiffness of the battery pack may increase to a threshold amount greater than a stiffness associated with a battery pack <NUM> with at least one battery module <NUM> not inserted. In some examples, the stiffness of the battery pack may increase to a threshold amount greater than a stiffness associated with an empty battery pack <NUM> (e.g., no battery modules inserted).

In the illustrative example, the battery pack <NUM> may comprise a portion of a seat upon which a passenger may sit. In such an example, the stiffness of the battery pack <NUM> may protect the passenger, at least in part, from an impact with another object. In various examples, the stiffness of the battery pack <NUM> may increase a torsional and/or lateral stiffness of the vehicle <NUM>. In such examples, the stiffness of the battery pack <NUM> may increase vehicle <NUM> handling, steering, and/or ride characteristics. In at least one example, one or more battery modules <NUM> in the battery pack <NUM> may be offset from other battery modules <NUM> in the battery pack <NUM>. For example, as illustrated in <FIG>, the bottom two battery modules <NUM> in the battery packs <NUM> are offset from a vertical stack of four other battery modules <NUM>. The offset design of one or more of the battery modules <NUM> may additionally increase a stiffness of a battery pack <NUM>, further improving torsional and/or lateral stiffness of the vehicle <NUM>.

In various examples, the battery module(s) <NUM> in a battery pack <NUM> may be configured substantially the same or similar. In such examples, the battery module(s) <NUM> in a battery pack <NUM> may be interchangeable. The battery module(s) <NUM> may include a battery housing including at least a base and four side walls. At least two of the four side walls may be configured with the couplers described above that are configured to slide along the rails <NUM>. In some examples, the at least two of the four side walls may be configured with module attachment mechanism configured to couple to casing attachment mechanism, such as those described above. In such examples, the casing attachment mechanism may include at least a rail or a coupler and the corresponding module attachment mechanism may include the other of the rail or the coupler. In some examples, the battery housing may additionally include a cover.

The battery housing may comprise a metal material, a ceramic material, a plastic material, a composite material, or a combination thereof. The base, four side walls, and the cover may comprise a same or similar material. In some examples, the materials of the base, four side walls, and/or the cover may be determined based on a high melting point and/or high durability. For example, a cover may include a stainless-steel material due to the high melting point and high durability of the stainless-steel. In various examples, the base, the four side walls, and/or the cover may include an insulating material (e.g., mica, silicone rubber, Teflon, etc.) coupled thereto (e.g., laminated, glued, etc.). In at least one example, the cover may comprise a metal material with an insulating material laminated thereto. In at least one other example, the battery housing may include a base configured with an insulating material coupled thereto and four side walls. In such an example, the battery housing may not include a cover.

In various examples, the battery housing may enclose a plurality of cells of the battery module <NUM>. Each cell of the plurality of cells may include a cylindrical cell, a pouch cell, a prismatic cell, a button cell, or the like. In at least one example, the cells in the plurality of cells are cylindrical cells. In some examples, the plurality of cells may be separated from one another by an insulating material. In some examples, the insulating material may comprise an insulating foam (e.g., silicone foam, silicone potting, etc.). In various examples, the insulating material disposed between individual cells of the plurality of cells may mitigate effects of thermal runaway of a single cell by isolating the cell from other cells proximate thereto. In such examples, the insulating material may enhance thermal runaway mitigation techniques by thermally isolating the cells from one another. In some examples, the insulating material may additionally explosively isolate cells from one another. In such examples, a failed cell may explode without substantially effecting other cells.

In some examples, the plurality of cells may be configured in multiple rows of cells. In some examples, the cells in a row of cells may be configured in series. In some examples, the cells in a row of cells may be configured in parallel. In some examples, each cell in a roll of cells may be configured with a positive polarity on a first side and a negative polarity on a second side opposite the first side. In such examples, a negative polarity of a first row of cells may be configured adjacent to a positive polarity of a second row of cells. In some examples, an adjacent row of cells may have an opposite polarity to a row of cells adjacent thereto. In such examples, a negative polarity of a first row of cells may be configured adjacent to a negative polarity of a second row of cells.

The plurality of cells may be electrically coupled to one another via one or more wires and/or one or more bus bars. In various examples, the cells may be coupled to the wire(s) and/or bus bar(s) via a water bond, a laser weld, or an ultrasonic weld. In some examples, the wire(s) and/or bus bar(s) may provide a means to build up a parallel or series drain associated with the plurality of cells. In various examples, a first set of wire(s) and/or bus bar(s) may be configured to carry a positive charge to a positive terminal of the battery module <NUM> and a second set of wire(s) and/or bus bar(s) may be configured to carry a negative charge to a negative terminal of the battery module <NUM>. In some examples, the positive terminal may be configured at a first end of a first side wall of the battery housing and the negative terminal may be configured at a second end of a second side wall of the battery housing. In some examples, the first side wall and the second side wall may be opposing walls (e.g., on opposite sides) of the battery housing. In some examples, the first end and the second end may be opposite ends of the opposing walls. In such examples, the positive terminal and the negative terminal may be substantially diagonally situated from one another.

As will be discussed in greater detail below with regard to <FIG>, the battery modules <NUM> of a battery pack <NUM> may be electrically coupled to one another in series. In the illustrative example, the negative terminal corresponding to a first battery module <NUM>(<NUM>) of a battery pack <NUM> may be coupled to a first negative bus bar <NUM>. Though the first battery module <NUM>(<NUM>) is illustrated as the top battery module <NUM> in a battery pack <NUM>, this is not intended to be limiting, and the first battery module <NUM>(<NUM>) may include the bottom battery in a stack of battery modules <NUM>, a first battery in a horizontal row of batteries, or the like. In various examples, the negative terminal corresponding to the first battery module <NUM>(<NUM>) may represent a most negative terminal of the battery pack <NUM>. The first negative bus bar <NUM> may be electrically coupled to the negative terminal of the first battery module <NUM>(<NUM>) at a first end and a high voltage junction box <NUM> at a second end.

In the illustrative example, the positive terminal corresponding to the first battery module <NUM>(<NUM>) may be electrically coupled to a negative terminal corresponding to a second battery module <NUM>(<NUM>). In various examples, each of the positive terminal and negative terminal of adjacent battery modules <NUM> may be electrically coupled, building a total voltage associated with the battery pack <NUM>. In various examples, a first positive bus bar <NUM> may electrically couple to the positive terminal corresponding to the last battery module <NUM> in the series at a first end and the high voltage junction box <NUM> at the second end. In such examples, the first positive bus bar <NUM> and the first negative bus bar <NUM> together may be configured to power the drive <NUM> module, in whole or in part.

As will be discussed in greater detail below with regard to <FIG>, the battery pack <NUM> may additionally include a second positive bus bar and a second negative bus bar (not illustrated in <FIG>). The second positive bus bar and the second negative bus bar may include high-voltage bus bars. In some examples, the second positive bus bar and the second negative bus bar may be coupled to the first positive and negative bus bars and/or the high voltage junction box 107at a first end and a connector at a second end. The connector may be configured to transfer excess power provided by the battery modules <NUM> to a battery balance box <NUM>, such as via cables, wires, and/or other electrical couplings. Additionally, the connector may be configured to receive power from the battery balance box <NUM>, such as that provided by a second set of battery modules <NUM> situated in a second battery pack <NUM>. In various examples, the battery balance box <NUM> may be configured to balance loads provided by the battery packs <NUM> of the vehicle <NUM>.

In various examples, the second positive bus bar and/or the second negative bus bar may be configured to de-energize in the event of a thermal runaway, short, over-voltage, over-temperature, under-temperature, vehicle controller electronic control unit failure and/or failure of a battery module <NUM>. As will be discussed in greater detail below, in some examples, de-energizing the second positive bus bar and/or the second negative bus bar may be based on a drop and/or a surge in voltage provided to the high voltage junction box <NUM> by the first positive bus bar and the first negative bus bar. By de-energizing the second positive bus bar and/or the second negative bus bar, the safety of the vehicle electrical system may be improved by at least removing the electrical connection between the battery balance box <NUM> and the drive module <NUM>. In the event of a thermal runaway, a single battery pack may be configured to power an electric load of the vehicle <NUM>.

Additionally, to further improve thermal runaway mitigation for batteries, the battery modules <NUM> may be configured to vent gases, such as gases emitted from one or more of the plurality of cells. In various examples, gases may vent out of an uncovered surface of the battery modules <NUM>. In such examples, the battery modules <NUM> may not include a cover, and gas may be free to vent from the plurality of cells into a space between modules and/or between a module and an interior surface of the casing. In some examples, the gases may vent out of the battery module via one or more battery module vents. In some examples, the gases may vent from an interior compartment of the battery module <NUM> into a corresponding battery module bay. The battery module bay may comprise a battery module space in which the battery module <NUM> occupies when inserted and/or a space surrounding at least the portion of the battery module <NUM>. In various examples, with a battery module <NUM> inserted into the battery module bay, the space surrounding the at least the portion of the battery module <NUM>, such as battery module <NUM>(<NUM>), may be bound at a bottom end by the rails <NUM> corresponding to the battery module <NUM>(<NUM>), such as rails <NUM>(<NUM>), and at a top end by the rails <NUM> corresponding to an adjacent battery module <NUM>, such as rails <NUM>(<NUM>) corresponding to battery module <NUM>(<NUM>). In such examples, the rails <NUM>(<NUM>) and <NUM>(<NUM>) may be configured to thermally insulate a battery module bay from another battery module bay (e.g., battery module <NUM>(<NUM>) from battery module <NUM>(<NUM>), and vice versa).

In various examples, each battery module bay of the battery pack may include one or more vents <NUM> (e.g., casing vents <NUM>) for venting gases outside of the vehicle. The casing vent(s) <NUM> may be configured to substantially equalize pressure between the battery module bay (e.g., space containing gas) and an atmosphere outside the vehicle. In some examples, the casing vent(s) <NUM> may comprise a breathable material (e.g., membrane) configured to filter contaminants from gases exiting the casing vent(s) <NUM>. In various examples, the casing vent(s) <NUM> may be configured to blow out (e.g., removed from casing to maximize a pressure equalization), such as when subjected to a threshold pressure differential between the battery module bay and the atmosphere outside the vehicle. The battery module vent(s) and the casing vent(s) <NUM> may prevent a battery module from over-pressurizing and/or over-heating, such as in the case of a cell failure and/or thermal runaway, thereby improving thermal runaway mitigation of the electrical system.

<FIG> is a side view of an example battery pack <NUM>, such as battery pack <NUM>, of an electrical system configured to provide power to a vehicle, in accordance with embodiments of the disclosure. The battery pack <NUM> includes a plurality of battery modules <NUM>, such as battery modules <NUM>. In various examples, the battery modules <NUM> in a battery pack <NUM> may be configured substantially the same, and thus may be interchangeable in the battery pack <NUM>.

In the illustrative example, the battery pack <NUM> includes six stacked battery modules <NUM>, the bottom two battery modules <NUM> being slightly offset from the other four battery modules <NUM>. In other examples, the battery pack <NUM> may include a greater or lesser number of battery modules <NUM>. Additionally, in other examples, the battery modules <NUM> may be disposed in different orientations within the battery pack <NUM>. The different orientations may include battery modules <NUM> being disposed substantially horizontally, both horizontally and vertically, vertically with no offset, horizontally and/or vertically with more battery modules <NUM> offset, or the like.

In various examples, the battery module(s) <NUM> may be inserted into the battery pack <NUM> via rails <NUM>, such as rails <NUM>(<NUM>) and <NUM>(<NUM>). In such examples, couplers <NUM> (e.g., module couplers), such as couplers <NUM>(<NUM>) and <NUM>(<NUM>) of the battery module(s) <NUM> may couple to the rails <NUM>(<NUM>) and <NUM>(<NUM>). In some examples, the rails <NUM> and the couplers <NUM> may comprise module attachment mechanisms. In the illustrative example, the couplers are configured in a substantially rectangular shape. In some examples, the couplers <NUM> may be configured such that at least a portion thereof may include a substantially circular shape, ovular shape, and/or other curved and/or linear shape. In various examples, the couplers <NUM> may extend the length of a side wall of the battery module <NUM>. In some examples, the couplers <NUM> may extend at least a portion of the length of the side wall of the battery module <NUM>.

In the illustrative example, the module attachment mechanisms include two couplers <NUM>(<NUM>) and <NUM>(<NUM>) on the battery modules <NUM> (e.g., module couplers) and two rails <NUM>(<NUM>) and <NUM>(<NUM>) of the battery pack <NUM>. The couplers <NUM>(<NUM>) and <NUM>(<NUM>) may be configured to couple to and slide along the rails <NUM>(<NUM>) and <NUM>(<NUM>). In other examples, the module attachment mechanism may include a single rail and a single module coupler disposed on the battery module <NUM>. In such examples, the single rail and the single module coupler may be configured to couple to a single casing coupler and a single rail of the battery pack <NUM>, respectively.

In some examples, the battery modules <NUM> may be secured into place in the battery pack <NUM> via one or more fasteners <NUM>. The fastener(s) <NUM> may include screws, bolts, rivets, pins, snap connectors, latches, spring fasteners, and/or any other mechanical fasteners. In at least one example, the fastener(s) <NUM> may be reusable components, such as, for example, those configured to rotate in to secure the battery module(s) <NUM> in place and rotate out to remove the battery module <NUM>. In various examples, the fastener(s) <NUM> may secure a side wall of the casing to the rails <NUM> and/or the battery module <NUM>. In some examples, the battery modules <NUM> may secure a plate <NUM> to the rails <NUM> and/or the battery module <NUM>. The plate <NUM> may include a metal material, a ceramic material, a plastic material, a composite material, or the like.

In various examples, the battery module(s) <NUM> may each be housed in a battery module bay <NUM> of the battery pack <NUM>. Each battery module bay <NUM>, such as battery module bays <NUM>(<NUM>) and <NUM>(<NUM>) may include a space in which to house a battery module <NUM>, such as battery modules <NUM>(<NUM>) and <NUM>(<NUM>), respectively, and a space surrounding at least a portion of the battery module <NUM>. The space surrounding the at least the portion of the battery module <NUM> may provide an air gap between two battery modules, such as the illustrated space between battery modules <NUM>(<NUM>) and <NUM>(<NUM>). In some examples, the space surrounding the at least the portion of the battery module <NUM> may assist in thermally isolating the battery modules <NUM> from one another, such as in the event of a battery module <NUM> thermal runaway (e.g., accelerating temperature increase).

In various examples, the battery modules <NUM> may be configured with one or more battery vents (not illustrated) to vent gases out of respective battery modules <NUM>. In some examples, the battery vent(s) may be disposed along a side wall of the battery modules <NUM>, extending at least partially along a length of the side wall. In at least one example, the battery vent(s) may be disposed above the couplers <NUM> on the side walls and may extend substantially the length of the side walls on opposing sides. In some examples, in the event of a thermal runaway of one or more cells of a battery module <NUM>, hot gases generated from the thermal runaway may exit the battery module via the battery vent(s). In various examples, the battery modules <NUM> may be configured with no cover or top surface. In such examples, the battery modules <NUM> may be configured to vent gases directly out of the uncovered top of the battery module <NUM> and into the associated battery module bay.

In various examples, the rails <NUM> may be configured to substantially preclude the hot gases exiting a battery module, such as battery module <NUM>(<NUM>) from substantially effecting a second battery module, such as battery module <NUM>(<NUM>), such as by substantially thermally isolating (e.g., insulating) the battery modules <NUM>. In such examples, the rails <NUM>(<NUM>) and <NUM>(<NUM>) may provide a barrier configured to limit gas flow between battery module bay <NUM>(<NUM>) and battery module bay <NUM>(<NUM>). Substantially precluding the hot gases from entering the battery module bay <NUM>(<NUM>), and consequently surrounding battery module <NUM>(<NUM>), may reduce an impact of the thermal runaway of battery module <NUM>(<NUM>) on an internal temperature of battery module <NUM>(<NUM>).

In some examples, the rails <NUM> may include a coating. The coating may include rubber, polyurethane, nylon, Teflon, silicone, polypropylene, polyethylene, or the like. In some examples, the coating may be configured to increase or decrease a frictional component between the rails <NUM> and the couplers <NUM> of the battery modules <NUM>. In some examples, the coating may be configured to assist in substantially thermally isolating one battery module, such as battery module <NUM>(<NUM>), from another battery module <NUM>, such as battery module <NUM>(<NUM>). In such examples, the coating may assist in preventing gases from passing through the couplers <NUM> between the battery module <NUM> and the respective rails <NUM>.

In some examples, gases exiting the battery module <NUM> via the battery vents may be configured to flow into the respective battery module bay <NUM>. In some examples, the gases may be configured to flow into a portion of a battery pack casing <NUM> (e.g., frame), such as casing <NUM>. In various examples, the portion of the battery pack casing <NUM> may include an opening <NUM> for gases to flow from the battery module <NUM> and/or the battery module bay <NUM> into the portion of the battery pack casing <NUM>.

In various examples, the battery pack casing <NUM> may include one or more vents <NUM>, such as vent(s) <NUM>. The vent(s) <NUM> may be configured to vent gases from inside the battery pack casing <NUM> to an external environment (e.g., outside the vehicle). In various examples, the vent(s) <NUM> may be configured to substantially equalize pressure between the battery module bay <NUM> and/or the portion of the battery pack casing <NUM> (e.g., space containing gas) and an atmosphere outside the vehicle. In some examples, the vent(s) <NUM> may comprise a breathable material (e.g., membrane) configured to filter contaminants from gases exiting the vent(s) <NUM>. In various examples, the vent(s) <NUM> may be configured to blow out, such as when subjected to a threshold pressure differential between the battery module bay <NUM> and/or the portion of the battery pack casing <NUM> and the atmosphere outside the vehicle. As a non-limiting example, blowing out based on such a pressure differential will cause the vent(s) <NUM> to be physically ejected from the battery pack casing <NUM>, creating a larger opening for pressure stabilization. In some examples, each battery module bay <NUM> may have associated therewith at least one vent <NUM> for expelling gases. In such examples, gases substantially trapped within the battery module bay <NUM> may be discharged out the respective vent(s) <NUM>.

In some examples, the battery modules <NUM> may each include a plurality of cells for generating electrical power. As will be discussed in further detail below with respect to <FIG>, the positive cell terminals may be electrically coupled to one another and the negative cell terminals may be electrically coupled to one another. The positive cell terminals may be coupled to a positive terminal <NUM>, to which the electrons from the plurality of cells flow, and the negative cell terminals may be coupled to a negative terminal <NUM>. In at least one example, the positive terminal <NUM> and the negative terminal <NUM> may be disposed on opposite side walls and on opposite ends of each battery module <NUM>. In the illustrative example, each battery module may be inserted into the battery pack <NUM> such that opposing polarities of battery modules are configured next to one another. For example, a negative terminal <NUM> associated with battery module <NUM>(<NUM>) is disposed proximate to a positive terminal <NUM> associated with battery module <NUM>(<NUM>), and so on.

In various examples, the battery modules <NUM> in a battery pack <NUM> may be configured in series. In the illustrative example, a positive terminal <NUM> associated with battery module <NUM>(<NUM>) is electrically coupled to a negative terminal <NUM> associated with battery module <NUM>(<NUM>), and a positive terminal <NUM> associated with battery module <NUM>(<NUM>) is electrically coupled to a negative terminal <NUM> associated with battery module <NUM>(<NUM>). Although not illustrated, adjacent positive terminals <NUM> and negative terminals <NUM> configured on respective opposing sidewalls to those illustrated in <FIG> may additionally be electrically coupled to one another. For example, a positive terminal <NUM> associated with battery module <NUM>(<NUM>) may be electrically coupled to a negative terminal <NUM> associated with battery module <NUM>(<NUM>), and so on.

In at least one example, the positive terminal <NUM> associated with battery module <NUM>(<NUM>) may include a most positive terminal in the battery pack <NUM> and the negative terminal <NUM> associated with the battery module <NUM>(<NUM>) may include the most negative terminal in the battery pack <NUM>. As illustrated in <FIG>, the positive terminal <NUM> associated with battery module <NUM>(<NUM>) may be coupled to a first positive bus bar <NUM> and the negative terminal <NUM> associated with battery module <NUM>(<NUM>) may be coupled to a first negative bus bar <NUM>.

The first positive bus bar <NUM> and the first negative bus bar <NUM> may be electrically coupled to a high voltage junction box <NUM> associated with the battery pack <NUM>. The high voltage junction box <NUM> may be configured to monitor a voltage and/or current provided by the first positive bus bar <NUM> and the first negative bus bar <NUM>, and provide power carried therefrom to a drive module associated with the battery pack <NUM>. The drive module may include one or more components for monitoring and/or controlling the vehicle associated with the battery pack <NUM>.

<FIG> is a close-up view of a battery pack <NUM>, such as battery pack <NUM>, housing a battery module <NUM>, such as battery module <NUM>, the close-up view illustrating venting capabilities of the battery module <NUM> and the battery pack <NUM>, in accordance with embodiments of the disclosure.

As discussed above, the battery module <NUM> may be inserted into the battery pack <NUM> via one or more rails <NUM>, such as the rails <NUM>. The rail(s) <NUM> may be configured to attached to couplers <NUM> located on a side wall <NUM> of the battery module <NUM>. In various examples, the side wall <NUM> may include one or more battery module vents <NUM>. The battery module vent(s) <NUM> may be configured to vent gases out of an interior compartment of the battery module <NUM>, and into a battery module bay of the battery pack <NUM> into which the battery module <NUM> is inserted. In some examples, the gases may vent into a portion <NUM> of a casing <NUM> (e.g., frame) of the battery pack <NUM>.

In various examples, the battery pack <NUM> may include one or more vents <NUM>, such as vent(s) <NUM>. The vent(s) <NUM> may be configured to vent gases from the battery module bay associated with the battery module <NUM> and/or the portion <NUM> of the casing <NUM> to an external environment (e.g., outside a vehicle associated with the battery pack <NUM>). In various examples, the vent(s) <NUM> may be configured to substantially equalize pressure between the interior compartment of the battery module <NUM>, the associated battery module bay and/or the portion <NUM> of the casing <NUM> (e.g., space containing gas) and the external environment. In some examples, the vent(s) <NUM> may comprise a breathable material (e.g., membrane) configured to filter contaminants from gases exiting the vent(s) <NUM>. In various examples, the vent(s) <NUM> may be configured to blow out, such as when subjected to a threshold pressure differential between the battery module bay and/or the portion of the battery pack casing <NUM> and the external environment. As a non-limiting example, blowing out based on such a pressure differential will cause the vent(s) <NUM> to be physically ejected from the battery pack casing, creating a larger opening for pressure stabilization. In the illustrative example, the battery module bay associated with battery module <NUM> includes two vents <NUM>. In other examples, each battery module bay may have a greater or lesser number of vent(s) <NUM>.

In various examples, the gases exiting the interior compartment of the battery module <NUM> may include hot gases generated by one or more cells of the battery module <NUM>, such as in thermal runaway of the cell(s). In such examples, the expelling of hot gases out of the battery module vent(s) <NUM> and the vent(s) <NUM> may substantially mitigate negative effects caused by the thermal runaway. For example, the escape of hot gases may reduce an effect the hot gases may have on another battery module in the battery pack <NUM>.

Additionally, to mitigate an effect of thermal runaway, the battery module <NUM> may include a cover <NUM> configured to reduce heat transfer. The cover <NUM> may comprise a sheet of metal material, ceramic material, composite material, plastic material, or a combination thereof. In at least one example, the cover <NUM> may comprise a sheet of stainless steel material. In some examples, the cover <NUM> may include an insulating material (e.g., mica, silicone rubber, Teflon, etc.), such as that laminated, glued, or otherwise affixed to the sheet. In various examples, the cover <NUM> may be configured to substantially thermally insulate the battery module <NUM> from another battery module inserted above the battery module <NUM>.

The battery module may also include a base <NUM>. The base <NUM> may include a metal material, ceramic material, composite material, plastic material, or a combination thereof. In some examples, the base <NUM> may be configured to reduce heat transfer between the battery module <NUM> and another battery module inserted below the battery module <NUM>. In such examples, the base <NUM> may include an insulating material (e.g., mica, silicone rubber, Teflon, etc.), such as that laminated, glued, or otherwise affixed to the base <NUM> (and/or constituting the entirety of the base). In various examples, the base <NUM> and the cover <NUM> may comprise a same or a different material and/or include a same or a different insulating material. In some examples, the battery module may include one or the other of an insulated base <NUM> or an insulated cover <NUM>.

<FIG> are illustrations of an example battery module <NUM>, such as battery module <NUM>. <FIG> is perspective view of the battery module <NUM> with a first terminal <NUM> located on a first side wall <NUM>(<NUM>) of the battery module and a second terminal <NUM> located on a second side wall <NUM>(<NUM>) of the battery module, the first terminal <NUM> and the second terminal <NUM> being located diagonally opposite one another. The diagonally opposite disposition of the first terminal <NUM> and the second terminal <NUM> may substantially negate a danger of electrical arcing between the first terminal <NUM> and the second terminal <NUM>. Accordingly, the disposition may increase the safety associated with use of the battery module <NUM>.

The first terminal <NUM> and the second terminal <NUM> may be coupled to a plurality of cells located within the battery module <NUM>. In various examples, the first terminal <NUM> may comprise a positive terminal. In such examples, the first terminal may be coupled to positive cell terminals associated with the plurality of cells and the second terminal <NUM>, a negative terminal, may be coupled to negative cell terminals associated with the plurality of cells. In some examples, the first terminal <NUM> may comprise a negative terminal. In such examples, the first terminal may be coupled to negative cell terminals associated with the plurality of cells and the second terminal <NUM>, a positive terminal, may be coupled to positive cell terminals associated with the plurality of cells.

The battery module <NUM> may include a third side wall <NUM>(<NUM>) and a fourth side wall <NUM>(<NUM>). The third side wall <NUM>(<NUM>) and the fourth side wall <NUM>(<NUM>) may include couplers <NUM>. In the illustrative example, the couplers <NUM> may extend the length of the third side wall <NUM>(<NUM>) and the fourth side wall <NUM>(<NUM>). In other examples, the couplers <NUM> may extend over a portion of the respective side walls <NUM>(<NUM>) and/or <NUM>(<NUM>). The couplers <NUM> may be configured to couple to the battery module <NUM> to rails of a battery pack, such as battery pack <NUM>. The battery module <NUM> may be inserted into the battery pack by sliding the couplers <NUM> along the rails of the battery pack. Once inserted, the battery module <NUM> may be secured in place via one or more fasteners, such as fastener(s) <NUM>. The fastener(s) may be secured into the battery module <NUM> via one or more attachment points <NUM>.

The first side wall <NUM>(<NUM>), the second side wall <NUM>(<NUM>), the third side wall <NUM>(<NUM>), and the fourth side wall <NUM>(<NUM>) may include a metal material, a ceramic material, a composite material, a plastic material, or a combination thereof. The side walls <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), and <NUM>(<NUM>) may include substantially the same or a different material. In some examples, the first side wall <NUM>(<NUM>) and the second side wall <NUM>(<NUM>) may include the same or a similar material. In some examples, the third side wall <NUM>(<NUM>) and the fourth side wall <NUM>(<NUM>) may include the same or a similar material.

The battery module <NUM> may additionally include a cover <NUM> and/or a base <NUM>. The cover <NUM> and/or the base <NUM> may include a metal material, a ceramic material, a composite material, a plastic material, or a combination thereof. The cover <NUM> and the base may include a similar or a different material. In some examples, the cover <NUM> and/or the base <NUM> may include an insulating material. In at least one example, the cover <NUM> and/or the base <NUM> may include a stainless-steel sheet with a mica material laminated thereto. In such examples, the cover may be configured to substantially thermally insulate the battery module <NUM> from another battery module inserted above the battery module <NUM> in the battery pack.

In various examples, the battery module <NUM> may not include a cover <NUM>. In such examples, the battery module <NUM> may be configured to vent gas out the uncovered top end of the battery module <NUM>. As illustrated in <FIG>, in some examples, the battery module <NUM> may include battery module vents <NUM>, such as battery module vent(s) <NUM>. The battery module vents <NUM> may be configured to vent gas out of the battery module <NUM>. In the illustrative example, the battery module <NUM> may include a plurality of battery module vents <NUM> disposed along the length of the third side wall <NUM>(<NUM>). In some examples, the battery module <NUM> may include one or more battery module vents disposed along a portion of the third side wall <NUM>(<NUM>) (e.g., less than the length thereof). In various examples, the fourth side wall <NUM>(<NUM>) may additionally include battery module vents <NUM>. In some examples, the fourth side wall <NUM>(<NUM>) may include battery module vents <NUM> disposed substantially the same as the battery module vents <NUM> disposed on the third side wall <NUM>(<NUM>).

<FIG> is a close-up view of a cross-section of the battery module <NUM>, the close-up view depicting the coupler <NUM> configured to secure the battery module <NUM> into the battery pack and a plurality of cells <NUM> located within the battery module <NUM>. As discussed above, the coupler <NUM> may be configured to couple to a rail system of the battery pack. The battery module <NUM> may be inserted into the battery pack by sliding the coupler <NUM> along a respective rail of the rail system.

As illustrated in <FIG>, the battery module <NUM> may include the plurality of cells <NUM> located in an internal compartment thereof. In various examples, the cells <NUM> may be configured in rows. As will be shown below with regard to <FIG>, in various examples, the rows of cells <NUM> may be offset from one another. In such examples, each cell <NUM> in a row may be disposed at an angle and/or a distance from a cell <NUM> in an adjacent row. In some examples, the angle may be about <NUM> degrees. In other examples, the angle may be greater or less than <NUM> degrees.

In various examples, each cell <NUM> in a row may be configured with a positive polarity (e.g., positive cell terminal) situated on a first side and a negative polarity (e.g., negative cell terminal) situated on a second side. In various examples, the polarity of the cells <NUM> of adjacent rows may opposite, such that the positive cell terminals of adjacent rows are situated proximate one another. In some examples, the polarity of the cells <NUM> of adjacent rows may be the same, such that the positive cell terminals of a first row are situated proximate the negative cell terminals of an adjacent row. In such examples, the positive and negative cell terminals of adjacent rows may be coupled to bus bars <NUM> and/or wires. For example, a first row may be associated with cells <NUM>(<NUM>) and a second row may be associated with cells <NUM>(<NUM>). Negative cell terminals associated with cells <NUM>(<NUM>) may be coupled to a first bus bar <NUM>(<NUM>). The first bus bar <NUM>(<NUM>) may carry the negative charge to a negative battery terminal (e.g., first terminal <NUM> or second terminal <NUM>). Positive cell terminals associated with the cells <NUM>(<NUM>) may couple to a second bus bar <NUM>(<NUM>). Additionally, negative cell terminals associated with the second row of cells <NUM>(<NUM>) may be coupled to the second bus bar <NUM>(<NUM>). Positive cell terminals associated with the second rows of cells <NUM>(<NUM>) may be coupled to a third bus bar <NUM>(<NUM>), as well as negative cell terminals associated with a third row of cells <NUM>(<NUM>). Positive cell terminals associated with the third row of cells <NUM>(<NUM>) may be coupled to a fourth bus bar <NUM>(<NUM>), and so on. In some examples, the second bus bar <NUM>(<NUM>), the third bus bar <NUM>(<NUM>), and/or the fourth bus bar <NUM>(<NUM>) may be coupled to a positive battery terminal (e.g., first terminal <NUM> or second terminal <NUM>). In such examples, the second bus bar <NUM>(<NUM>), the third bus bar <NUM>(<NUM>), and/or the fourth bus bar <NUM>(<NUM>) may carry a charge from the cells <NUM> to the positive battery terminal.

<FIG> are illustrations of example internal components of a battery module <NUM>, such as battery module <NUM>, in accordance with embodiments of the disclosure. <FIG> depicts a plurality of battery cells <NUM> configured in rows <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), through <NUM>(N). In some examples, each of the rows <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>) through <NUM>(N) may include thirty-six (<NUM>) cells. In other examples, each of the rows <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>) through <NUM>(N) may include a greater or lesser number of cells.

As discussed above, the cells <NUM> associated with a first row <NUM>(<NUM>) and the cells <NUM> associated with a second row <NUM>(<NUM>) may be offset a distance and/or an angle from one another. In at least one example, the offset may include an angle of about <NUM> degrees. In other examples, the offset may include an angle greater or less than <NUM> degrees. In various examples, cells <NUM> associated with alternating rows, such as the first row <NUM>(<NUM>) and the third row <NUM>(<NUM>) may be aligned with one another.

In various examples, the cells <NUM> associated with a row <NUM>(<NUM>) may be configured with a positive cell terminal on a first side (e.g., top side) of the cells <NUM> and a negative cell terminal on a second side (e.g., bottom side) of the cells. In some examples, the cells <NUM> may be configured with a positive cell terminal in a top-most centered position of the cell <NUM> and a negative cell terminal situated slightly below and encircling the positive cell terminal. In some examples, the cell terminals of opposite polarity of the first row <NUM>(<NUM>) and the second row <NUM>(<NUM>) may be coupled to a first bus bar or wire. Additionally, the cell terminals of opposite polarity of the second row <NUM>(<NUM>) and the third row <NUM>(<NUM>) may be coupled to a second bus bar or wire.

In some examples, negative cell terminals associated with the first row <NUM>(<NUM>) may be coupled to a first terminal <NUM> (e.g., negative terminal) of the battery module <NUM>. In such examples, the first terminal <NUM> may include a most negative charge of the battery module <NUM>. In various examples, bus bars coupled to positive and negative cell terminals of adjacent rows <NUM>(<NUM>) though <NUM>(N) may be configured to carry a charge to a second terminal <NUM> (e.g., positive terminal) of the battery module <NUM>. In the illustrative example, the first terminal <NUM> and the second terminal <NUM> may be diagonally disposed on opposite side walls of the battery module. The diagonal disposition of the first terminal <NUM> and the second terminal <NUM> may reduce a probability of electrical arcing occurring between the first terminal <NUM> and the second terminal <NUM>, thereby improving safety associated with battery module <NUM> use.

<FIG> is top view of the plurality of battery cells <NUM> electrically coupled to the first terminal <NUM> and the second terminal <NUM>. In various examples, the plurality of cells <NUM> may be thermally insulated from one another by an insulating material <NUM>. In some examples, the insulating material <NUM> may comprise an insulating foam (e.g., silicone foam, silicone potting, etc.). In various examples, the insulating material <NUM> disposed between individual cells of the plurality of cells <NUM> may mitigate effects of thermal runaway of a single cell by isolating the cell from other cells proximate thereto. In such examples, the insulating material <NUM> may reduce thermal runaway effects. In some examples, the insulating material <NUM> may additionally explosively isolate cells from one another. In such examples, a failed cell may explode without substantially affecting other cells.

As discussed above, in some examples, negative cell terminals associated with a first row <NUM>(<NUM>) may be coupled to a first main bus bar <NUM>. In such examples, the first main bus bar <NUM> may carry a negative charge to the first terminal <NUM>. In various examples, positive cell terminals and negative cell terminals associated with adjacent rows, such as first row <NUM>(<NUM>) and <NUM>(<NUM>), may be coupled to bus bars <NUM> or wires. In some examples, the bus bars <NUM> or wires may connect directly to the second terminal <NUM>. In some examples, the bus bars <NUM> or wires may carry a charge to the second terminal <NUM> via a second main bus bar <NUM>. For example, positive cell terminals associated with the first row <NUM>(<NUM>) and negative cell terminals associated with the second row <NUM>(<NUM>) may couple to a first bus bar <NUM>(<NUM>) or wire. The positive cell terminals associated with the second row <NUM>(<NUM>) may be coupled to the second bus bar <NUM>(<NUM>) or wire. The first bus bar <NUM>(<NUM>) and the second bus bar <NUM>(<NUM>) may couple to the second main bus bar <NUM> and deliver a charge to the second terminal <NUM> via the second main bus bar <NUM>. In some examples, cells may be positioned in a same direction such that gases vent out in the direction of orientation of the cell. In some examples, orientations of the cells may be determined to optimize gas flow and, hence, thermal control of the cell and/or to mitigate potential thermal runaway effects.

<FIG> is an illustration of example battery pack <NUM>, such as battery pack <NUM>, including first bus bars <NUM>(<NUM>) and <NUM>(<NUM>) and second bus bars <NUM>(<NUM>) and <NUM>(<NUM>), in accordance with embodiments of the disclosure. The first bus bars <NUM>(<NUM>) and <NUM>(<NUM>) may include a first positive bus bar <NUM>(<NUM>) and a first negative bus bar <NUM>(<NUM>). The second bus bars <NUM>(<NUM>) and <NUM>(<NUM>) may include a second positive bus bar <NUM>(<NUM>) and a second negative bus bar <NUM>(<NUM>). The second positive bus bar <NUM>(<NUM>) and the second negative bus bar <NUM>(<NUM>) may include high-voltage bus bars.

In various examples, the battery modules <NUM> in the battery pack <NUM> may be configured in series. In such examples, a positive terminal of a first battery module <NUM>(<NUM>) may be electrically coupled to a negative terminal of a second battery module <NUM>(<NUM>), a positive terminal of the second battery module <NUM>(<NUM>) may be electrically coupled to a negative terminal of a third battery module <NUM>(<NUM>), and so on.

In the illustrative example, the first positive bus bar <NUM>(<NUM>) may carry a most positive charge from a battery module <NUM> at the end of the series (e.g., a bottom battery module in a stack) to a high voltage junction box <NUM> of the vehicle and the first negative bus <NUM>(<NUM>) bar may carry a most negative charge of the battery pack from a first battery module <NUM>(<NUM>) to the high voltage junction box <NUM>.

In various examples, the second positive bus bar <NUM>(<NUM>) and the second negative bus bar <NUM>(<NUM>) may additionally be electrically coupled to the high voltage junction box <NUM> at a first end <NUM> and a connector <NUM> at a second end <NUM>. In some examples, the connector <NUM> may include a floating connector. In such examples, the connector <NUM> may be configured to accommodate relative misalignment of plugs, such as that caused by vibration and/or other movement of the vehicle. In various examples, the connector <NUM> may be configured to transfer power provided by the battery modules <NUM> to a battery balance box (e.g., battery balance box <NUM>), such as via a cable, wire, or other electrical coupling. Additionally, the connector <NUM> may be configured to receive power from the battery balance box, such as that provided by a second set of battery modules situated in a second battery pack. The battery balance box may be configured to maximize the capacity of each battery pack by modulating the charge and/or discharge of batteries based on the capacity associated therewith. In various examples, the second positive bus bar <NUM>(<NUM>) and the second negative bus bar <NUM>(<NUM>) may be configured to carry power from the high voltage junction box <NUM> associated with the battery pack <NUM> and/or carry power to the high voltage junction box <NUM> associated with the battery pack <NUM>, such as when the battery balance box determines that an unequal amount of power is provided by two or more battery packs of a vehicle.

In various examples, the second positive bus bar <NUM>(<NUM>) and/or the second negative bus bar <NUM>(<NUM>) may be configured to de-energize in the event of a thermal runaway and/or failure of a battery module associated with the battery pack. In some examples, the second positive bus bar <NUM>(<NUM>) and/or the second negative bus bar <NUM>(<NUM>) may de-energize based at least in part on a drop and/or surge in voltage provided to the high voltage j unction box <NUM> by the first positive bus bar <NUM>(<NUM>) and the first negative bus bar <NUM>(<NUM>). In some examples, the second positive bus bar <NUM>(<NUM>) and/or the second negative bus bar <NUM>(<NUM>) may be de-energized based on a drop and/or surge in voltage exceeding a threshold voltage, such as that indicative of a thermal runaway and/or failure of a battery module <NUM>. In various examples, the high voltage junction box <NUM> may detect the drop and/or surge in voltage and may de-energize one or both of the respective second bus bars <NUM>(<NUM>) and <NUM>(<NUM>). In some examples, the battery balance box may detect the drop and/or surge in voltage and may de-energize one or both of the respective second bus bars <NUM>(<NUM>) and <NUM>(<NUM>). For example, the second battery module <NUM>(<NUM>) in the battery pack <NUM> may short circuit due to a failure of one or more cells corresponding to the third battery. The voltage provided by the battery pack may consequently drop resulting in a total voltage provided to high voltage junction box <NUM> being less than an expected voltage (e.g. less than a voltage required to run the components of the high voltage junction box <NUM>, less than a threshold voltage, etc.). Based on the voltage drop, the high voltage junction box <NUM> and/or battery balance box may sense a failure in the battery pack <NUM> and de-energize the second positive bus bar <NUM>(<NUM>) and/or the second negative bus bar <NUM>(<NUM>).

<FIG> and <FIG> illustrate example processes in accordance with embodiments of the disclosure. These processes are illustrated as logical flow graphs, each operation of which represents a sequence of operations that may be implemented manually, such as in configuring a battery pack for operation in a vehicle. The order in which the operations are described is not intended to be construed as a limitation, and any number of the described operations may be combined in any order and/or in parallel to implement the processes.

<FIG> depicts an example process <NUM> of inserting battery modules into a battery pack. In various examples, the battery modules of the battery pack may be interchangeable. In such examples, a first battery module may include the same or substantially similar components as a second battery module, and so on.

At operation <NUM>, the process may include inserting the first battery module into a casing of a battery pack via a first pair of rails, wherein a positive terminal of the first battery module is located at a first end of the casing. In various examples, the first pair of rails may comprise a part of the casing. In some examples, the rails may be coupled to the casing, such as via one or more fasteners. The first battery module may include couplers disposed on opposing side walls and configured to slide along the pairs of rails.

As discussed above, the pairs of rails may include a coating. In various examples, the coating may be configured to increase a frictional component between the rails and the couplers of the battery module. In some examples, the coating may be configured to substantially prevent gases from flowing between a first battery module bay above the first pair of rails and a second battery module bay below the first pair of rails. In such examples, the coating may be configured to substantially thermally insulate one battery module bay from another battery module bay, and consequently the first battery module from the second battery module.

At operation <NUM>, the process may include inserting the second battery module into the casing of the battery pack via a second pair of rails, wherein a negative terminal of the second battery module is located at the first end of the casing. To align the positive terminal of the first battery module and the negative terminal of the second battery module, the second battery module may be rotated about a vertical axis about <NUM> degrees relative to the first battery module. In various examples, the positive terminal of the first battery module and the negative terminal of the second battery module may be electrically coupled to one another.

At operation <NUM>, the process may include inserting a third battery module into the casing of the battery pack via a third pair of rails, wherein a positive terminal of the third battery module is located at the first end of the casing. To align the negative terminal of the second battery module and the positive terminal of the third battery module, the third battery module may be rotated about a vertical axis about <NUM> degrees relative to the second battery module. In various examples, the positive terminal of the second battery module and the negative terminal of the third battery module may be electrically coupled to one another.

At operation <NUM>, the process may include inserting a fourth battery module into the casing of the battery pack via a fourth pair of rails, wherein a negative terminal of the fourth battery module is located at the first end of the casing. To align the positive terminal of the third battery module and the negative terminal of the fourth battery module, the fourth battery module may be rotated about a vertical axis about <NUM> degrees relative to the third battery module. In various examples, the positive terminal of the third battery module and the negative terminal of the fourth battery module may be electrically coupled to one another.

At operation <NUM>, the process may include inserting a fifth battery module into the casing of the battery pack via a fifth pair of rails, wherein a positive terminal of the fifth battery module is located at the first end of the casing. To align the negative terminal of the fourth battery module and the positive terminal of the fifth battery module, the fifth battery module may be rotated about a vertical axis about <NUM> degrees relative to the fourth battery module. In various examples, the positive terminal of the fourth battery module and the negative terminal of the fifth battery module may be electrically coupled to one another.

At operation <NUM>, the process may include inserting a sixth battery module into the casing of the battery pack via a sixth pair of rails, wherein a negative terminal of the sixth battery module is located at the first end of the casing. To align the positive terminal of the fifth battery module and the negative terminal of the sixth battery module, the sixth battery module may be rotated about a vertical axis about <NUM> degrees relative to the fifth battery module. In various examples, the positive terminal of the fifth battery module and the negative terminal of the sixth battery module may be electrically coupled to one another.

At operation <NUM>, the process may include mechanically securing the first, second, third, fourth, fifth, and sixth battery modules to the respective pairs of rails with one or more fasteners. The fasteners may include any kind of mechanical fasteners (e.g., screws, bolts, pins, snap connectors, latches, spring-type fasteners, etc.) that may be releasably attached to the battery module, the rails, and/or the casing of the battery pack. In some examples, the battery modules may be mechanically coupled to the rails by securing a plate to an end of a rail and a side wall of the battery modules proximate the end of the rails. In at least one example, the plate may be coupled to the end of the rail via two fasteners and coupled to the battery module via two fasteners.

<FIG> depicts an example process <NUM> for coupling battery modules, such as battery module <NUM>, of a battery pack, such as battery pack <NUM>, to one another.

At operation <NUM>, the process may include coupling a positive terminal associated with a first battery module to a negative terminal associated with a second battery module. In various examples, the positive terminal associated with the first battery module may be disposed substantially above the negative terminal associated with the second battery module.

At operation <NUM>, the process may include coupling a positive terminal associated with the second battery module to a negative terminal associated with a third battery module. In various examples, the positive terminal associated with the second battery module may be disposed substantially above the negative terminal associated with the third battery module.

At operation <NUM>, the process may include coupling a positive terminal associated with the third battery module to a negative terminal associated with a fourth battery module. In various examples, the positive terminal associated with the third battery module may be disposed substantially above the negative terminal associated with the fourth battery module.

At operation <NUM>, the process may include coupling a positive terminal associated with the fourth battery module to a negative terminal associated with a fifth battery module. In various examples, the positive terminal associated with the fourth battery module may be disposed substantially above and offset from the negative terminal associated with the second battery module.

At operation <NUM>, the process may include coupling a positive terminal associated with the fifth battery module to a negative terminal associated with a sixth battery module. In various examples, the positive terminal associated with the fifth battery module may be disposed substantially above and offset from the negative terminal associated with the sixth battery module. In various examples, the couplings between the battery modules may include electrical couplings via bus bars or wires.

Claim 1:
An electrical system configured to supply electric power to an electric load of a vehicle, the electrical system comprising:
a casing (<NUM>) comprising:
a first set of rails (<NUM>) coupled to a first interior surface of the casing; and
a second set of rails (<NUM>) coupled to a second interior surface of the casing and spaced from the first set of rails;
a first battery module (<NUM>) comprising a first housing mechanically coupled to the first set of rails; and
a second battery module (<NUM>) comprising a second housing mechanically coupled to the second set of rails, the second housing separated a distance from the first housing, the distance defining a gap between the first battery module and the second battery module to thermally insulate the second battery module from the first battery module,
wherein at least one of the first set of rails or the second set of rails comprises a coating configured to:
restrict gases from traveling between the gap and another gap; and
increase a frictional component between the at least one of the first set of rails or the second set of rails and at least one of the first housing or the second housing.