Vehicle energy-storage systems

The present disclosure is directed to energy storage systems for vehicles. In some aspects, the energy storage system may be used to power an electric automobile. The energy storage system may include a plurality of individual battery cells. The cells may be cylindrical and have a positive and negative terminal on the same side. The cells may be physically and/or electrically organized into bricks. The bricks may be physically and/or electrically organized into modules. The modules may be physically and/or electrically organized into strings. The strings may be physically and/or electrically organized into a pack. In some embodiments, packs, strings, modules and/or bricks may include flexible circuitry and/or may be liquid cooled.

FIELD

The present application relates generally to energy-storage systems, and more specifically to energy-storage systems for vehicles.

BACKGROUND

Electric-drive vehicles may reduce the impact of fossil-fuel engines on the environment and increase the sustainability of automotive modes of transportation. Energy-storage systems are essential for electric-drive vehicles, such as hybrid electric vehicles, plug-in hybrid electric vehicles, and all-electric vehicles. Size, efficiency, and safety are important considerations for these energy-storage systems. Spatially efficient storage, improved thermal management, and balance among battery cells, promote these goals.

SUMMARY

The systems and methods of this disclosure each have several innovative aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope as expressed by the claims that follow, its more prominent features will now be discussed briefly. The electrical and mechanical arrangement of the components described herein have several advantages over the prior art. For example, the individual battery cells may be subject to less cycling, thus increasing battery lifetime. The individual batteries cells may include terminals on only one end of a cylindrical body—simplifying manufacturing. The configurations of battery cells within liquid cooled modules may provide increased energy storage density.

In some embodiments, modular energy-storage systems are described. An electric vehicle battery pack may include a plurality of independently removable battery strings. Each battery string may include a plurality of battery modules. Each battery module may include a plurality of electrochemical cells. The cells may be organized into rows and columns. In some aspects, cells are electrically coupled in parallel and/or in series. The electrochemical cells may be disposed within various cell holder structures, and may be electrically connected by flexible circuitry. Coupling of various components within the battery pack, strings, and/or modules may be accomplished by pressure fitting, snap fitting, welding such as laser welding, application of adhesive chemicals, or other coupling methods. In some embodiments, battery packs, strings, and/or modules may be liquid cooled.

DETAILED DESCRIPTION

The following description is directed to certain implementations for the purpose of describing the innovative aspects of this disclosure. However, a person having ordinary skill in the art will readily recognize that the teachings herein can be applied in a multitude of different ways.FIGS.1-16illustrate exemplary components, methods, and systems for use in electric vehicles. Exemplary systems may include a battery pack organized as strings having current carriers and battery modules. Such systems may be implemented in any type of vehicle. For example, the vehicle may be a car, truck, semi-truck, motorcycle, plane, train, moped, scooter, or other type of transportation. Furthermore, the vehicle may use many types of powertrain. For example, the vehicle may be an electric vehicle, a fuel cell vehicle, a plug-in electric vehicle, a plug-in hybrid electric vehicle, or a hybrid electric vehicle. Though described with reference to vehicle components, the exemplary current carriers and battery modules are not limited to use in vehicles. For example, the current carriers and battery modules may be used to power domestic or commercial appliances.

In some embodiments, a battery management system design implemented with multiple battery strings for an electric vehicle is disclosed. In this implementation, there is one string control unit for each battery string and multiple module monitoring boards for module voltages and temperature measurements. A single battery pack controller is used to simplify the interaction of other controllers in the vehicle with the multiple strings. Each battery string is also coupled to a current sensor and a set of contactors.

FIG.1depicts a block diagram of an example electric vehicle drive system10including a battery management system16as described herein. The electric vehicle drive system10includes the battery or voltage source11, an inverter12coupled to the battery11, a current controller13, a motor14, and load15, and the battery management system16. The battery11can be a single phase direct current (DC) source. In some embodiments, the battery11can be a rechargeable electric vehicle battery or traction battery used to power the propulsion of an electric vehicle including the drive system10. Although the battery11is illustrated as a single element inFIG.1, the battery11depicted inFIG.1is only representational, and further details of the battery11are discussed below in connection withFIG.2.

The inverter12includes power inputs which are connected to conductors of the battery11to receive, for example, DC power, single-phase electrical current, or multi-phase electrical current. Additionally, the inverter12includes an input which is coupled to an output of the current controller13, described further below. The inverter12also includes three outputs representing three phases with currents that can be separated by12electrical degrees, with each phase provided on a conductor coupled to the motor14. It should be noted that in other embodiments inverter12may produce greater or fewer than three phases.

The motor14is fed from voltage source inverter12controlled by the current controller13. The inputs of the motor14are coupled to respective windings distributed about a stator. The motor14can be coupled to a mechanical output, for example a mechanical coupling between the motor14and mechanical load15. Mechanical load15may represent one or more wheels of the electric vehicle.

Controller13can be used to generate gate signals for the inverter12. Accordingly, control of vehicle speed is performed by regulating the voltage or the flow of current from the inverter12through the stator of the motor14. There are many control schemes that can be used in the electric vehicle drive system10including current control, voltage control, and direct torque control. Selection of the characteristics of inverter12and selection of the control technique of the controller13can determine efficacy of the drive system10.

The battery management system16can receive data from the battery11and generate control signals to manage the battery11. Further details of the battery management system16are discussed in connection withFIGS.2-3below.

Although not illustrated, the electric vehicle drive system10can include one or more position sensors for determining position of the rotor of the motor14and providing this information to the controller13. For example, the motor14can include a signal output that can transmit a position of a rotor assembly of the motor14with respect to the stator assembly motor14. The position sensor can be, for example, a Hall-effect sensor, potentiometer, linear variable differential transformer, optical encoder, or position resolver. In other embodiments, the saliency exhibited by the motor14can also allow for sensorless control applications. Although not illustrated, the electric vehicle drive system10can include one or more current sensors for determining phase currents of the stator windings and providing this information to the controller13. The current sensor can be, for example, a Hall-effect current sensor, a sense resistor connected to an amplifier, or a current clamp.

It should be appreciated that while the motor14is depicted as an electrical machine that can receive electrical power to produce mechanical power, it can also be used such that it receives mechanical power and thereby converts that to electrical power. In such a configuration, the inverter12can be utilized to excite the winding using a proper control and thereafter extract electrical power from the motor14while the motor14is receiving mechanical power.

The battery strings26can include a plurality of modules, each of which in turn can include a plurality of cells. Within each battery string26, the constituent modules and cells can be connected in series as symbolically depicted inFIG.2. In some embodiments, the voltage source11can include six battery strings26that can be connected to or disconnected from the power buses20,25. The battery strings26can be implemented with various different types of rechargeable batteries made of various materials, such as lead acid, nickel cadmium, lithium ion, or other suitable materials. In some embodiments, each of the battery strings can output about 375V-400V if charged about 80% or more.

The current sensors28can be connected in series with the respective battery strings26between the high and low power buses20,25. As shown inFIG.2the current sensor28can be connected to the positive side of the respective battery strings26to measure the current discharged from the battery strings26. In other embodiments, the current sensors28can be connected to the battery strings26otherwise to measure the current flow due to discharging of the battery strings26.

The switches21and22can be contactors configured to connect the battery strings26to the power buses20,25or disconnect the battery strings26from the power buses20,25in response to the respective control signals24. The switches21can be implemented with any suitable contactors capable of handling the level of current and voltage as needed in connection with, for example, the battery strings26, the power buses20,25, and the load15(FIG.1) within the electric vehicle drive system10(FIG.1). In some embodiments the switches21and22can be implemented with mechanical contactors with solenoid inside. In some embodiments, the switches21can be powered by one or more drivers in the battery management system16. Although in the illustrated example inFIG.2, the switches21(e.g.,21n) and the switches22(e.g.,22n) are controlled by the same respective control signals24(e.g.,24n), in other embodiments, the switches21(e.g.,21n) can be controlled by respective positive bus connect control signals while the switches22(e.g.,22n) can be controlled by respective negative bus connect control signals.

The battery management system16can include a plurality of passive and/or active circuit elements, signal processing components, such as analog-to-digital converters (ADCs), amplifiers, buffers, drivers, regulators, or other suitable components. In some embodiments, the battery management system16can also include one or more processors to process incoming data to generate outputs, such as the control signals24. In some embodiments, the battery management system16can also include one or more components for communicating and sending and receiving data within the battery management system16and/or with other components or circuitries in the electric vehicle. For example, the various components and circuits within the system10, including components in the battery management system16can be in communication with one another using protocols or interfaces such as a CAN bus, SPI, or other suitable interfaces. And in some embodiments, the processing of incoming data can be at least in part performed by other components not in the battery management system16within the electric vehicle as the battery management system16communicates with other components.

FIG.3Ais another block diagram of an example voltage source and battery management system according to one embodiment. InFIG.3A, one exemplary battery string26nof the plurality of battery strings26ofFIG.2is illustrated, and accordingly, the corresponding current sensor28n, switches21n,22n, and connect control signal24nare illustrated. Also illustrated is a fuse31ncorresponding to the battery string26n, and although not illustrated, the battery strings26a,26b, . . . ,26n, . . . inFIG.2may each also have corresponding fuse31a,31b, . . . ,31n, . . . . The battery string26nincludes a plurality of battery modules38n_1,38n_2, . . . ,38n_k(individually or collectively referred to herein as38nfor the battery string26n), each sending battery module telemetry data to respective module monitoring boards36n_1,36n_2, . . . ,36n_k(individually or collectively referred to herein as36nfor the battery string26n) of the battery management system16. The battery management system16includes a string control unit34nfor the battery string26nin communication with the battery modules38n_1,38n_2, . . . ,38n_kfor the battery string26n. The battery management system16can include an analog-to-digital converter (ADC)32nfor processing analog data from the battery string26n. In some embodiments, the ADC32ncan be internal to the string control unit34n, and in other embodiments, the ADC32ncan be separate from the string control unit34n. Although not illustrated, the battery management system16also may include respective string control units34a,34b, . . . ,34n, . . . and respective ADCs32a,32b, . . . ,32n, . . . for the plurality of battery strings26a,26b, . . . ,26n, . . . illustrated inFIG.2. The battery management system16also includes a battery pack controller31, which controls a switch driver35and is in communication with the plurality of string control units34.

In the illustrated embodiment, the nth battery string26nhas k number of battery modules38nandknumber of module monitoring boards36n. In some embodiments, one battery string26may include, for example 6 battery modules38in series. In some embodiments, one battery module38may include, for example, 16 battery bricks in series, and a battery brick may include 13 battery cells in parallel. Also, in some embodiments the voltage source11(FIG.1) of the electric vehicle drive system10(FIG.1) can include 1 battery pack, which includes, for example 6 battery strings26. A battery cell can be, for example, a Li-ion cell, and the battery pack for the electric vehicle drive system10can provide power greater than, for example 500 kW.

Each of the battery modules38may be assembled with an interface, such as a board or plane (not shown), that is configured to gather various battery module telemetry data such as voltage, current, charge, temperature, etc. to be communicated to the module monitoring boards36. In the illustrated embodiment, the module monitoring boards36n_1,36n_2, . . . ,36n_kcommunicate with the string control unit34nusing a communication protocol, such as isoSPI. In the illustrated embodiment, the module monitoring boards36ncan gather, for example, temperature and voltage data of the respective modules38nand communicate them to the string control unit34n. Also in some embodiments, analog measurement data from the battery modules38nand the battery string26ncan be processed with the ADC32nfor further digital processes at the string control unit34nand the battery pack controller31, for example. In some embodiments, the module monitoring boards36ncan be individually and directly in communication with the string control unit34n, and in other embodiments, the module monitoring boards36ncan be collectively and/or indirectly in communication with the string control unit34nthrough a communication bus or in a daisy chained configuration.

The string control unit34ncan be a processor configured to monitor status of the battery modules38nand the battery string26n, test and monitor isolation of the battery string26n, manage temperature of the battery modules38nand the battery string26n, execute battery management algorithms, and generate the control signal24nfor controlling one or both of the switches21nand22nof the battery string26n. Similarly, the respective string control units34a,34b, . . . ,34n, . . . for the battery strings26a,26b, . . . ,26n, . . . illustrated inFIG.2can perform the same functions for the respective battery strings26so that the battery management system16as a whole outputs the control signals24a,24b, . . . ,24n, . . . from the respective string control units34a,34b, . . . ,34n, . . . to the corresponding switches21a,21b, . . . ,21n, . . . , and22a,22b, . . . ,22n, . . . . In the illustrated embodiment, the string control unit34ncan also be in communication with the current sensor28nand receive, for example, the current reading I_n of the battery string26n. Also, the string control unit34ncan be coupled to the fuse31nto receive, for example, an indication of a tripped circuit or a blown fuse.

The battery pack controller31in the illustrated embodiment can be in communication with the plurality of string control units34a,34b, . . . ,34n, . . . . In some embodiments, various data from the one or more of the battery strings (e.g., string_a, string_b, . . . , string_n, . . . ) can be communicated using CAN buses and the battery management system16may include a plurality of CAN bus transceivers (not shown). The battery pack controller31is also coupled to the switch driver35, which can provide power to the switches21and22(e.g. contactors) of the battery strings26, and the battery pack controller31can be in further communication with other devices, components, or modules of the electric vehicle. In certain instances, the battery pack controller31can communicate to the switch driver35to cut power and disconnect all the switches21and22. For example, when the battery pack controller16may be configured to disconnect all the switches21and22when it receives a signal that indicates an air bag is deployed. Also, in certain instances, the string control unit34nmay receive high temperature data from one of the modules38nand send a warning signal to the battery pack controller31. In such instances, the built-in redundancy of the multi-string battery structure and the battery management system allows disconnecting the potentially troubling battery string without affirmatively determining whether disconnecting the battery string is required.

It can be advantageous to implement a battery management system for an electric vehicle as disclosed herein. With conventional thinking, the parallel system looks like it will cost n times the cost of a conventional system, where is n is the number of parallel strings. However, in most safety critical Lithium battery system, redundancy is typically needed anyway, to improve false positive or negative trips. Also, the battery pack split into multiple battery strings allows use of lower current contactors, reducing cost while increasing modularity. In traditional systems with lithium batteries, if a voltage sensor fails, most battery management systems are forced to open switches or contactors of the whole pack because of a risk of overcharge which can lead to a fire or explosion. Because of this, traditional systems include a redundant voltage measurement. The voltage measurement could be another board such as an additional module monitoring board, or a Hardware Overvoltage device on the cell level.

With a multi-string system, in case of a broken voltage sensor or current sensor or temperature sensor, one string can be independently taken out of the pack and the battery pack still delivers power with the remaining strings. With a battery management system implemented as disclosed herein, added voltage redundancy may not be necessary for reliability because the level of redundancy is already built into the multi-string management system. If a voltage sensor fails, a cautious approach may be taken, removing the string, and the vehicle will still have power for the application from the remaining strings.

By avoiding redundant temperature, voltage and current sensors in a multi-string battery pack, costs can be kept low while reliability and safety can be increased. The control unit can be programmed to be safer than traditional systems, with the ability to independently open and close contactors compared to traditional battery management systems, because other strings provide redundant backup.

The multi-string battery structure and battery management system disclosed herein can also be advantageous in providing continuous power to the electric vehicle as the distributed currents in the multi-string structure and the battery management system allow increased continuous power capability of the battery pack. In some instances continuous current draw of over 1 kA can be implemented using the disclosed system. Furthermore, because the multiple battery strings distribute the total output current over multiple branches, the disclosed battery structure and battery management system allows the system to be implemented with components such as fuses, current sensors, and contactors that are cost- and size-effective as the current in one battery string is lower than is present in a non-multi-string system, and thus the individual components in a string need not carry or measure as high a current. For example, with six separate strings each handling 300 A maximum output can produce a total maximum output of 1.8 kA. Although this multi-string system may use six sets of contactors, fuses, and current measurement devices, the total cost of six sets of these devices each suitable for 300 A operation can be lower total cost as well as higher accuracy operation than a single set suitable for 1.8 kA operation. Also, the built in redundancy, among other features, of the system disclosed herein allows high reliability as faulty strings can be disconnected and removed from operation while the remaining strings can continue to provide power to the electric vehicle. The multi-string battery structure and the battery management system also allow modularity, adaptability, and scalability depending on the size and type of the vehicle and the level of power needed for the vehicle's intended use. The battery management system disclose herein provides the benefits of having multiple battery strings while effectively and efficiently managing a great number of contactors and fuses.

FIG.3Bis a block diagram of an example voltage source and battery management system such as shown inFIG.3Awherein the module monitoring boards36are provided in the same enclosure with the respective batteries they are associated with and collect data from to form coupled modules39n_lthrough39n_k. Data transfer between the monitoring boards36and the string control unit34may be provided by a daisy chain bus that enters and exits each module39. Each module39further has a positive power terminal33and a negative power terminal37which mate adjacent modules with a series electrical connection as will be described further below.

FIGS.4A to4Cillustrate an external view of one exemplary physical implementation of a module39fromFIG.3B. The module39has a housing42, which may be a molded polymer housing. One side41of the housing, which will be referred to herein as the “plug side,” includes a power terminal43provided in the form of a plug, which may form the positive power terminal33ofFIG.3Bfor example. Beneath the output terminal43are data input/output plug(s) or pin(s)46, which in this example form a two wire data bus connection. This portion of the module is shown in more detail inFIG.4B. Visible inFIG.4Bsurrounding the power terminal43is a window47which forms a fluid tight seal against an inner frame (not shown inFIG.4) sealing the inside of the housing42from the outside of the housing42as will be explained further below. Referring back toFIG.4A, also provided on the plug side41are a first opening52ato a first coolant flow channel in the housing and a second opening54ato a second coolant flow channel in the housing. These openings52a,54amay also be formed as plugs. As will be described further below, one of these coolant flow channels may introduce cooling fluid into the housing, while the other coolant flow channel may allow cooling fluid to exit the housing.

On the opposite side of the module39from the plug side41is a “socket side”49. This side is illustrated inFIG.4C. The socket side49includes a power terminal44provided in the form of a socket, which may form the negative power terminal37ofFIG.3Bfor example. Beneath the power terminal44are a pair of data input/output sockets48. These sockets may be sealed with an inner frame and an outer frame47in the same manner as the plugs43and46on the plug side. Also provided on the socket side49are a first opening52bto the first coolant flow channel in the housing and a second opening54bto the second coolant flow channel in the housing. These openings52a,54amay also be formed as sockets.

To form a string26of modules39, a plurality of modules can be arranged in an adjacent manner, with the plugs on the plug side of one module mating with the sockets on the socket side of an adjacent module. This connects positive and negative power terminals in series and daisy chains the data input/outputs as shown inFIG.3B. The fluid couplings between plugs52aand54aof one module and sockets52band54bof an adjacent module form continuous fluid inlet and outlet manifolds extending along the string. Any number of modules can be mated together in a series to form a string36. In one implementation, six adjacent modules39form a string26. At one end of such a string will be a positive power terminal (on the “positive end module”) and at the other end of the string will be a negative power terminal (on the “negative end module”). These power terminals can be electrically coupled to the respective positive and negative bus bars20and25as shown inFIG.3B. Any number of such strings can be placed adjacent to each other in a dimension perpendicular to the length of each string, to form a multiple string battery pack as illustrated inFIG.2.

FIG.5is a combination block diagram and schematic illustrating example battery electrical connections and some aspects of physical component layout of a module39. The housing42may be molded as two half modules denoted A and B inFIG.5that are separated by an inner wall53. Running along the length of the module39on each side and through the inner wall53are coolant fluid channels52cand54c. The outer housing shell, the inner wall53, and the coolant fluid channels52cand54cmay be molded as one monolithic polymer piece.

Each half module may contain a plurality of connected battery cells55. In one implementation, sets of battery cells56of the plurality of battery cells are connected in parallel. These parallel connected sets are referred to herein as “bricks.” In each half module, a collection of bricks56may be connected in series. It will be appreciated that any number of parallel connected battery cells may form a brick, and any number of bricks may be connected in series in each half module depending on the desired output voltage and output current capacity is desired. In one implementation, a brick is twelve parallel connected lithium ion cells, and each half module contains eight bricks connected in series.

In the implementation ofFIG.5, the series connected bricks in each half module are further connected in series with a connection59that extends into both of the two half modules A and B as described further below. The negative side of the most negative brick56is connected to the negative output terminal of the module, which may be socket44. The positive side of the most positive brick is connected to the positive output terminal of the module, which may be plug43. In one specific implementation, this results in sixteen bricks of twelve parallel cells each connected in series between terminal43and terminal44of the module.

The module monitoring board36may connect to each side of each brick to measure the voltage across each brick. Thus, the module monitoring board36may also extend into both of the two half modules A and B as also described further below. The module monitoring board36may also connect to temperature or a variety of other sensors (not shown) placed in each half module. The module monitoring board36also connects to the input/output connections46and48on the plug side41and socket side49of the module39.

During operation, the battery cells55may be cooled by being submerged in a cooling fluid so as to have direct contact between the cell housings and the cooling fluid. This is in contrast with having the cooling fluid routed through closed channels where only the channel walls are in direct contact with the cell housings. To implement this, a fluid inlet channel52cincludes at least one opening57aand57bbetween the channel52cand the interior of each half module in an area proximate to the inner wall53. The term “proximate to” in this context means that at least some of the opening57aor57bis positioned closer to the face of the inner wall53in that half module than at least some of the battery cell55housings in that half module. The openings57aand57bmay abut the face of the inner wall53. The openings57aand57bmay be located at least partly between all the battery housings in a half module and the respective face of the inner wall53such that the openings57aand57bare located at least partly “under” all the battery housings in that half module. The openings57aand57bmay be located entirely between all the battery housings in a half module and the respective face of the inner wall53such that the openings57aand57bare located entirely under all the battery housings in that half module.

Also provided in each half module is at least one fluid outlet opening58aand58b. These outlet openings58aand58bmay be proximate to the other side of each half module from the inlet openings57aand57band remote from the inner wall53. The term “remote from” in this context means that at least some of the opening58aor58bis positioned closer to the outer face of the module in that half module than at least some of the battery cell55housings in that half module. The openings58aand58bmay abut the inner face of an outer panel of the module. The openings58aand58bmay be located at least partly between all the battery housings in a half module and the outer face of the module such that the openings58aand58bare located at least partly over all the battery housings in that half module. The openings58aand58bmay be located entirely between all the battery housings in a half module and the outer face of the module such that the openings58aand58bare located entirely over all the battery housings in that half module. With this configuration, cooling fluid enters the half modules proximate to the inner wall53, is pushed over the battery cells for cooling and then out of each half module on the other side of the battery cells near the outer face of the module. It is advantageous to have the channels52cand54cbe positioned vertically near the top of the module (relative to the ground) when the modules are packaged into strings and packs installed in a vehicle, as then gravity assists in ensuring that each half module is completely filled with cooling fluid to submerge all the batteries in each half module.

FIG.6is an exploded view of the components of one half module (in this example it corresponds to module B ofFIG.5) illustrating one example physical construction thereof. The housing42has a cavity for the half module components which has the internal wall53at the far end thereof. A lower battery holder62has recesses63to hold the bottom ends of cylindrical batteries55. The battery bottom ends may be secured into the recesses with adhesive. The batteries may have both a positive terminal65and a negative terminal67on their upper ends. The lower battery holder62is dropped into the cavity and rests on a shoulder67at the junction of the inner wall53and the housing42forming the cavity and the batteries55are installed therein.

The module monitor board36is placed in a slot74which may be integral to the housing42and that extends from the printed circuit plane66to the printed circuit plane (not shown) in the other half module on the other side of the inner wall53. Connectors on each side of the module monitor board36are coupled to mating connectors on the underside of the printed circuit planes. The connection59ofFIG.5that connects the two half modules in series may be implemented with a conductive metal (e.g. copper) rod (designated59inFIG.6also). The rod59is coupled to the underside of the printed circuit planes of each half module, and extends between them in a channel72which may be similar in configuration as the above described slot74but sized and shaped for the rod59instead of the module monitoring board36.

An upper battery holder64slides over the tops of the cylindrical batteries55. On top of this upper battery holder64is a printed circuit plane66, which may be a flex circuit. Metal (e.g. copper) traces on the flex circuit form the circuit connections illustrated in each half module shown inFIG.5. Contacts may be provided in or on the printed circuit plane that can be electrically coupled to the positive terminals65and negative terminals67of the batteries55by, for example, laser welding. An output terminal, in this example the socket44described above, is provided on the flex circuit on a polymer mount that has a frame45around its perimeter. The polymer mount is sealed to the surface of the printed circuit66in a fluid tight manner with adhesive and/or other means such as laser welding around the perimeter of the frame45. A cover68is placed over the printed circuit plane66and is sealed to the housing42at the top of the cavity containing the above described components. The inner face of the cover68around the window47rests on the frame45around the power and data connectors. The perimeter of the window47may then be liquid tight sealed such as by laser welding to the top surface of the frame45, thereby sealing against leakage the half module cavity to implement fully submerged battery cooling.

FIG.7illustrates the components ofFIG.6in an assembled configuration without the housing42surrounding them. The printed circuit plane66is positioned between the upper battery retainer64and the cover68. The connection rod59and the module monitoring board36extend through the upper battery retainer64and connect to the bottom side of the printed circuit plane66.

FIG.8shows the plug side cavity of the housing42with no components installed. The shoulder67runs along the bottom of the cavity along the wall. The bottom battery retainer62may sit on this shoulder67and may also rest on a pad84in the middle, thereby forming a gap between the face of the inner wall53and the bottom of the bottom battery retainer62. A cooling fluid channel57a(e.g. also shown inFIG.5) extends along the inner wall53through the shoulder67and through the wall of the cooling fluid channel52cto fluidly connect the cooling fluid channel52cin the area proximate to the inner wall53and at least partially aligned with the gap between the bottom of the bottom battery retainer62and the inner wall53described above.

FIG.9shows the bottom of the plug side cavity ofFIG.8, with the housing42cut away proximate to the inner wall53through approximately the center of the shoulder67. As seen inFIG.9, the channel57aextends through the wall separating the inside of the cooling fluid channel52cand the interior of the half module.

FIG.10shows a housing42with a bottom battery retainer62installed in the cavity. The battery bottoms can rest in recesses63. The bottom battery retainer includes coolant flow openings92which allows the coolant to flow over the batteries from underneath.FIGS.11A and11Billustrate the bottom battery retainer further outside of the housing42.FIG.11Billustrates the back side of the bottom battery retainer62.

FIG.12shows a housing42with batteries installed and an upper battery retainer64holding the batteries in place.FIGS.13A and13Billustrate the upper battery retainer64. The upper battery retainer has grooves96for coolant flow up from the batteries which then flow to the outlet58a.

FIG.14shows a housing42with a printed circuit plane66coupled to the tops of the batteries.FIG.15shows the back side of the cover41that is installed over the printed circuit plane and may be laser welded to the housing42around the edge.

FIG.16illustrates a battery tray with multiple strings of multiple modules39. An inlet and outlet for coolant98aand98bare provided for coolant to enter the tray and be distributed among the modules39as described above.

The foregoing description details certain embodiments of the systems, devices, and methods disclosed herein. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the devices and methods can be practiced in many ways. As is also stated above, it should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to including any specific characteristics of the features or aspects of the technology with which that terminology is associated. The scope of the disclosure should therefore be construed in accordance with the appended claims and any equivalents thereof.

It is noted that the examples may be described as a process. Although the operations may be described as a sequential process, many of the operations can be performed in parallel, or concurrently, and the process can be repeated. In addition, the order of the operations may be rearranged. A process is terminated when its operations are completed. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.

Those of skill would further appreciate that any of the various illustrative schematic drawings described in connection with the aspects disclosed herein may be implemented as electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two, which may be designed using source coding or some other technique), various forms of program or design code incorporating instructions, or combinations of both.

The various circuitry, controllers, microcontroller, or switches, and the like, that are disclosed herein may be implemented within or performed by an integrated circuit (IC), an access terminal, or an access point. The IC may comprise a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, electrical components, optical components, mechanical components, or any combination thereof designed to perform the functions described herein, and may execute codes or instructions that reside within the IC, outside of the IC, or both.

The functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a tangible, non-transitory computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. A computer-readable medium may be in the form of a non-transitory or transitory computer-readable medium.

Though described herein with respect to a vehicle, as would be readily appreciated by one of ordinary skill in the art, various embodiments described herein may be used in additional applications, such as in energy-storage systems for wind and solar power generation. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosed current carrier and battery module. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.