Thermal management of battery systems

Abstract

A battery system has a plurality of battery cells including a first battery cell. Each battery cell includes a casing that encloses an anode and a cathode. The battery system also includes a first fluid circulation system having a plurality of fluid conduits including a first fluid conduit adjacent the first battery cell, wherein the first fluid circulation system is configured to circulate a first fluid through the battery system in a first direction. The battery system also includes a second fluid circulation system having a plurality of fluid conduits including a first fluid conduit adjacent the first fluid conduit of the first fluid circulation system. The second fluid circulation system is configured to circulate a second fluid through the battery system in a second direction opposite the first direction.

Description

BACKGROUND

[0001] Batteries store energy in order to provide power to electrical devices when needed. Most batteries will generate heat as current is delivered to or drawn from the battery. If the generated heat is not dissipated, the battery will rise in temperature. Most batteries have an effective operating temperature range, and if the battery exceeds a maximum operating temperature, the battery can become inefficient or even fail. In some cases, after a slight rise in temperature, the battery can be able to dissipate heat to its surroundings through a simple heat sink or without any thermal management being performed. In other cases, a more specific thermal management system is needed to dissipate the heat generated by the battery.

[0002] Typically, as the amount of current flowing into or out of a battery increases, the amount of heat generated also increases. Therefore, thermal management of a battery can be particularly important during charging when a large amount of current is fed into the battery or when an electrical load requires a high current output. SUMMARY

[0003] Systems and methods for thermal management of a battery system are disclosed herein. Beneficially, the systems and methods utilize two fluids to control the temperature of battery cells in a battery system.

[0004] Thus, in a first aspect, the disclosure provides a battery system, the battery system comprising:

[0005] a plurality of battery cells comprising a first battery cell, each battery cell comprising a casing surrounding an anode and a cathode;

[0006] a first fluid circulation system comprising a plurality of fluid conduits, the plurality of fluid conduits comprising a first fluid conduit adjacent to the first battery cell, wherein the first fluid circulation system is configured to circulate a first fluid through the battery system in a first direction; and

[0007] a second fluid circulation system comprising a plurality of fluid conduits, the plurality of fluid conduits comprising a first fluid conduit adjacent to the first fluid conduit of the first fluid circulation system, wherein the second fluid circulation system is configured to circulate a second fluid through the battery system in a second direction opposite the first direction.

[0008] In one embodiment, each battery cell is a soft pack cell.

[0009] In another embodiment, the first fluid is a dielectric fluid.

[0010] In another embodiment, the second fluid is a heat exchange fluid having a higher thermal conductivity than the first fluid.

[0011] In another embodiment, the first fluid conduit of the first fluid circulation system is at least partially defined by a housing of the first battery cell such that the fluid in the first fluid conduit is in fluid contact with the first battery cell.

[0012] In another embodiment, the first fluid conduit of the first fluid circulation system and the first fluid conduit of the second fluid circulation system are separated by a shared conduit wall.

[0013] In another embodiment, the plurality of battery cells includes a second battery cell, wherein the plurality of fluid conduits of the first fluid circulation system includes a second fluid conduit adjacent to the second battery cell, and

[0014] wherein the first fluid conduit of the second fluid circulation system intervenes between the first fluid conduit of the first fluid circulation system and the second fluid conduit of the first fluid circulation system.

[0015] In another embodiment, the conduit wall between the first fluid circulation system and the second fluid circulation system includes a fire suppression passage configured to open when the conduit wall exceeds a predetermined temperature.

[0016] In another embodiment, the first fluid circulation system is configured to serially circulate the first fluid through the plurality of fluid conduits of the first fluid circulation system.

[0017] In another embodiment, the battery system further includes a pump configured to circulate the first fluid through the first fluid circulation system.

[0018] In another embodiment, the battery system further includes a controller configured to operate the pump to maintain the first fluid at an elevated pressure.

[0019] In another embodiment, the controller is configured to control the pump to adjust the pressure of the first fluid to control swelling of the plurality of cells.

[0020] In another embodiment, the controller is configured to control the valve to adjust the pressure of the first fluid to control swelling of the plurality of cells.

[0021] In a second aspect, the present disclosure provides a battery system, the battery system comprising:

[0022] a plurality of battery cells including a first battery cell, each battery cell including a housing enclosing an anode and a cathode;

[0023] a first fluid circulation system comprising:

[0024] a pump configured to circulate a first fluid through the first fluid circulation system, and

[0025] a plurality of fluid conduits including a first fluid conduit, the first fluid conduit being at least partially defined by a housing of the first battery cell such that a first fluid in the first fluid conduit is in fluid contact with the first battery cell,

[0026] a controller configured to operate the pump of the first fluid circulation system; and

[0027] a second fluid circulation system including a plurality of fluid conduits including a first fluid conduit adjacent to the first fluid conduit of the first fluid circulation system, wherein the second fluid circulation system is configured to circulate a second fluid through the battery system.

[0028] In another embodiment, the controller is configured to control the pump to adjust a pressure of the first fluid in order to control an expansion of the plurality of cells.

[0029] In another embodiment, the controller is configured to control the valve to adjust a pressure of the first fluid in order to control an expansion of the plurality of cells.

[0030] In another embodiment, the pump is configured to circulate the first fluid through the battery system in a first direction, and the second fluid circulation system is configured to circulate the second fluid through the battery system in a second direction opposite the first direction.

[0031] In another aspect, the disclosure provides a method of charging a power battery, the method comprising:

[0032] connecting electrical contacts of the battery system to electrical terminals of a charging station;

[0033] connecting fluid couplings of the battery system to fluid terminals of the charging station;

[0034] receiving a charging current from the plurality of battery cells through the electrical contacts;

[0035] dissipating heat from the battery cells to a first fluid in a first fluid circulation system of the battery system;

[0036] dissipating heat from the first fluid to a second fluid in a second fluid circulation system of the battery system; and

[0037] receiving a flow of the second fluid from the fluid terminals of the charging station through the fluid couplings, circulating the second fluid through the second fluid circulation system, and returning the second fluid to the fluid terminals of the charging station through the fluid couplings.

[0038] In one embodiment of the method, the electrical contacts of the battery system and the fluid couplings of the battery system are disposed in a common plug housing.

[0039] In another embodiment of the method, the method further includes circulating the first fluid through the first fluid circulation system.

[0040] In another embodiment of the method, the first fluid is maintained at an elevated pressure to limit expansion of each of the plurality of battery cells.

[0041] In another embodiment of the method, the method further includes sending sensor data to the charging station to control flow of the second fluid through the second fluid circulation system.

[0042] These and other aspects, advantages, and alternatives will become apparent to those of ordinary skill in the art by reading the following detailed description, with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0043] The accompanying drawings are included to provide a further understanding of the systems and methods of the present disclosure and are incorporated in and constitute a part of this specification. The drawings are not necessarily to scale, and the dimensions of various elements can have been exaggerated for clarity of presentation. The drawings illustrate one or more embodiment(s) of the present disclosure and, together with the description, serve to explain the principles and operations of the present disclosure.

[0044] Figure 1 is a schematic plan view of a battery system according to another embodiment of the present disclosure;

[0045] Figure 2 is a schematic plan view of a battery system according to another embodiment of the present disclosure;

[0046] Figure 3 is a schematic plan view of a battery system according to another embodiment of the present disclosure;

[0047] Figure 4 is a schematic plan view of a battery system according to another embodiment of the present disclosure;

[0048] Figure 5 is a schematic plan view of a battery system according to another embodiment of the present disclosure;

[0049] Figure 6 is a schematic view of a vehicle charging system according to an embodiment of the present disclosure; and

[0050] Figure 7 is a flowchart of a charging method according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0051] Example systems and methods are described herein. It should be understood that the words “example” and “exemplary” are used herein to mean “serving as an example, instance, or illustration.” Any implementation or feature described herein as “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations or features. In the detailed description that follows, reference will be made to the accompanying drawings, which form a part of this specification. In the drawings, similar symbols typically identify similar components, unless the context dictates otherwise. Other embodiments can be utilized and other changes can be made without departing from the scope of the subject matter presented herein.

[0052] The example embodiments described herein are not intended to be limiting. It will be readily understood that the aspects of this disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein.

[0053] As used herein, “about” with respect to a measured value means + / - 5%.

[0054] The use of the word “first,” “second,” etc. in this text is merely a label and does not require that the items being referenced be limited to the first or second item, position, or level of importance, unless otherwise indicated. Further, a reference to, for example, “the second” item does not require or exclude the presence of, for example, “the first” or lower numbered item and / or “the third” or higher numbered item.

[0055] Reference herein to “one embodiment” or “one example” means that a particular feature, structure, or characteristic described in connection with this example is included in at least one implementation. The appearances of the phrase “one embodiment” or “one example” in various places in the specification are not necessarily all referring to the same example or are not necessarily referring to one example versus another example.

[0056] As used herein, a system, apparatus, device, structure, article, element, component, or hardware that is "configured to" perform a particular function is capable of performing that function without further modification. In other words, a system, apparatus, device, structure, article, element, component, or hardware that is "configured to" perform a particular function is specifically selected, created, implemented, utilized, programmed, and / or designed for that function. As used herein, "configured to" denotes existing characteristics of a system, apparatus, device, structure, article, element, component, or hardware which enable the system, apparatus, device, structure, article, element, component, or hardware to perform the specified function without further modification. For purposes of this disclosure, a system, apparatus, device, structure, article, element, component, or hardware described as being "configured to" perform a particular function can additionally or alternatively be described as "adapted to" perform that function, and / or as "operative to" perform that function.

[0057] In the following description, numerous specific details are set forth to provide a thorough understanding of the concepts disclosed herein. The concepts disclosed herein, however, can be practiced without some or all of these details. In other instances, well known devices and / or processes have not been described in detail in order to avoid unnecessarily obscuring the concepts disclosed herein. While some concepts will be described in conjunction with specific examples, it will be understood that these examples are not intended to be limiting.

[0058] The systems and methods described herein are suitable for thermal management of a battery using two fluid circulation systems. As a battery cell in a battery system generates heat, the battery cell dissipates heat to a first fluid in a first fluid circulation system. In turn, the first fluid dissipates heat to a second fluid in a second fluid circulation system.

[0059] In some embodiments, the battery system can be part of a vehicle, such as an electric or hybrid vehicle. In other embodiments, the battery system can be part of a stationary energy storage device. For example, the battery system can be part of an energy storage system for delivering electrical energy to an electric vehicle. As another example, the battery system can be part of an energy storage system that stores energy when excess electrical energy is available. For example, the battery system can be part of a wind farm or a solar system. Other uses for the battery system are also possible.

[0060] With reference to the drawings, Figure 1 A battery system is shown (see Figure 5battery pack 130 having a plurality of battery cells 132 including a first battery cell 134. The first battery cell 134 can include a housing that encloses an anode 134A and a cathode 134B so as to form an electrical storage device. The battery pack 130 can also include portions of a first fluid circulation system 140 and portions of a second fluid circulation system 150. The first fluid circulation system 140 can be configured to circulate a first fluid through the battery pack 130. Also, as described in greater detail below, the first fluid circulation system 140 can include fluid passageways and components external to the battery pack 130. To circulate the fluid through the battery pack 130, the first fluid circulation system 140 can have a plurality of fluid conduits 142 including a first fluid conduit 144.

[0061] The first fluid conduit 144 of the first fluid circulation system 140 can be adjacent to the first battery cell 134 such that the first fluid 141 in the first fluid conduit 144 can absorb energy from or provide energy to the first battery cell 134. During operation of the battery system, when current is delivered to or drawn from the battery cells 132, some of the energy can be converted into heat within the plurality of battery cells 132 including the first battery cell 134. As a result, the first battery cell 134 can rise in temperature. The temperature differential between the first battery cell 134 and the first fluid 141 in the first fluid conduit 144 can cause energy to dissipate from the first battery cell 134 to the first fluid 141 in the first fluid conduit 144. The first fluid 141 in other fluid conduits 142 of the first fluid circulation system 140 in the battery pack 130 can similarly absorb heat from the respective adjacent battery cells 132. On the other hand, if the ambient environment is cold when the battery pack begins operation, the battery cells 132 can initially be cold. Thus, energy from the first fluid 141 in the first fluid conduit 144 can be transferred to the battery cells to warm the battery cells.

[0062] Similar to the first fluid circulation system 140, the second fluid circulation system 150 can be configured to circulate a second fluid through the battery pack 130. Also, as described in greater detail below, the second fluid circulation system 150 can include fluid passageways and components external to the battery pack. To circulate the second fluid 151 through the battery pack 130, the second fluid circulation system 150 can have a plurality of fluid conduits 152 including a first fluid conduit 154.

[0063] The first fluid conduit 154 of the second fluid circulation system 150 can be adjacent to the first fluid conduit 144 of the first fluid circulation system 140 such that the second fluid 151 in the first fluid conduit 154 of the second fluid circulation system 150 can absorb energy from the first fluid conduit 144 of the first fluid circulation system 140. As the first fluid 141 in the first fluid circulation system 140 absorbs energy from the battery cells 132 during operation of the battery system, the first fluid 141 in the first fluid conduit 144 can rise in temperature. The temperature difference between the first fluid 141 in the first fluid conduit 144 of the first fluid circulation system 140 and the second fluid 151 in the first fluid conduit 154 of the second fluid circulation system 150 can cause energy to dissipate from the first fluid 141 to the second fluid 151 in the first fluid conduit 154 of the second fluid circulation system 150. Again, other fluid conduits 152 of the second fluid circulation system 150 within the battery pack 130 can similarly absorb heat from corresponding adjacent fluid conduits 142 of the first fluid circulation system 140.

[0064] The first fluid circulation system 140 can be configured to circulate the first fluid 141 through the battery pack 130. In some embodiments, the first fluid circulation system 140 can include a pump to circulate the first fluid 141 through the first fluid circulation system 140 including the fluid conduits 142. As used herein, the term pump includes any device that uses energy to move a fluid. For example, the pump can be formed by any actuator or mechanism that moves a fluid, such as a rotary pump, piston pump, or other pump. In other embodiments, the first fluid 141 can circulate through the first fluid circulation system 140 as a result of changes in temperature and convection, for example, through thermal siphoning.

[0065] Similarly, the second fluid circulation system 150 can be configured to circulate the second fluid 151 through the battery pack 130. In some embodiments, the second fluid circulation system 150 can include a pump to circulate the second fluid 151 through the second fluid circulation system 150 including the fluid conduits 152. In other embodiments, the second fluid 151 can circulate through the second fluid circulation system 150 as a result of changes in temperature and convection.

[0066] In some embodiments, a first fluid circulation system 140 may be configured to circulate a first fluid 141 through the battery pack 130 in a first direction, and a second circulation system 150 may be configured to circulate a second fluid 151 through the battery pack 130 in a second direction opposite to the first direction. The opposite direction of flow of the respective fluids 141 and 151 within the respective fluid circulation systems 140 and 150 of the battery pack 130 may refer to the direction in which the fluids are traveling within adjacent fluid conduits. For example, the first fluid 141 and the second fluid 151 may travel in opposite directions through adjacent fluid conduits, such that the adjacent fluid conduits provide a counter-current arrangement. Such a configuration in… Figure 1 In one embodiment, the flow of the first fluid 141 through the first fluid conduit 144 of the first fluid circulation system 140 is in the opposite direction to the flow of the second fluid 151 through the first fluid conduit 154 of the second fluid circulation system 150.

[0067] Alternatively, the opposite direction of flow of the respective fluids 141 and 151 in the respective fluid circulation systems 140 and 150 within the battery pack 130 can refer to the overall direction in which the fluid is traveling through the battery pack 130. For example, the first fluid circulation system 140 can be configured to circulate the first fluid 141 through the battery pack 130 in a series flow configuration, wherein the first fluid circulation system 140 is guided through a plurality of battery cells 132 in the battery pack 130 and flows from a first end of the battery pack 130 to a second end of the battery pack 130. Similarly, the second fluid circulation system 150 can be configured to circulate the second fluid 151 through the battery pack 130 in a series flow configuration in the opposite direction (i.e., from the second end of the battery pack 130 to the first end of the battery pack 130). In such embodiments, the adjacent fluid conduits of the first and second fluid circulation systems can have parallel or cross flow configurations, while the overall flow of the first fluid 141 and the second fluid 151 is in opposite directions. In other embodiments, the first fluid circulation system 140 and the second fluid circulation system 150 may be configured to circulate the respective first fluid 141 and second fluid 151 through the battery pack 130 without flowing in the opposite direction.

[0068] The battery pack 130 may include a housing 160 that holds the battery cells 132 and fluid conduits 142 of the first fluid circulation system 140 and the second fluid circulation system 150. Furthermore, the battery pack may include electrical terminals 162 on the exterior of the housing 160 for connecting the battery pack 130 to a power source or electrical load. The battery pack 130 may further include electrical connectors 164 that electrically connect the battery cells 132 within the battery pack 130. The electrical connectors 164 may connect the battery cells 132 in series, in parallel, or in combination, such as connecting a plurality of battery cells 132 in series to form a group, and connecting groups of battery cells in parallel.

[0069] Electrical connections can include any conductive structure used to transfer current from one battery cell to another. For example, an electrical connection can include tabs that act as terminals for each of the battery cells, with the tabs connected to each other by wires or conductive rods. Other electrical connections are also possible.

[0070] In some embodiments, the electrical connection 164 may be included within the first fluid circulation system 140. For example, as... Figure 1 As shown, the electrical connector 164 between the battery cells 132 in the battery pack 130 can be positioned within the first fluid circulation system 140 such that the first fluid 141 surrounds the electrical connector 164. This configuration allows any heat generated by the flow of current through the electrical connector 164 to dissipate into the first fluid 141. Furthermore, in some embodiments, the electrical connector 164 can pass through an opening in the second fluid circulation system 150 to avoid interference between the electrical connector 164 and the second fluid circulation system 150. For example, the fluid conduit 152 of the second fluid circulation system 150 can include a sealed orifice through the fluid conduit 152, which allows the electrical connector 164 to pass through the fluid conduit 152 without contacting the second fluid 151 in the second fluid circulation system 150. Moreover, in some embodiments, depending on the type of fluid used in the first fluid circulation system 140 and the second fluid circulation system 150, the electrical connector 164 can contact the first fluid 141 and / or the second fluid 151.

[0071] In other embodiments, at least a portion of the electrical connections between battery cells may be disposed on the exterior of the battery pack housing. Such a battery pack... Figure 2 As shown in the diagram, the battery pack 230 includes a plurality of battery cells 232 disposed within the housing 260. The battery pack 230 may also include a fluid conduit 242 of a first fluid circulation system 240 and a fluid conduit 252 of a second fluid circulation system 250. Both the fluid conduit 242 of the first fluid circulation system 240 and the fluid conduit 252 of the second fluid circulation system 250 may also be disposed within the housing 260.

[0072] Electrical connections 264 that connect the battery cells 232 together can be provided. A first set 266 of the electrical connections 264 can be disposed within the first fluid circulation system 240 such that the electrical connections 264 of the first set 266 are surrounded by the first fluid 241. Thus, the first fluid 241 can provide direct cooling of the electrical connections 264. Also, the battery cells 232 of the battery pack 230 can be positioned to one side of the battery pack 230 such that some electrical terminals of the battery cells 232 extend out of the housing 260. For example, a second set 268 of the electrical connections 264 can be disposed on the exterior of the housing 260 of the battery pack 230 and connect the terminals of the battery cells 232 that extend out of the housing 260.

[0073] Also, in other embodiments, all of the electrical connections between the battery cells can be disposed on the exterior of the housing of the battery pack (e.g., as shown in the embodiment of FIG. 3, which is described in more detail below). Figure 4

[0074] In one embodiment, the battery cells 132 are soft-pack battery cells. For example, the casing of the battery cells 132 can be in the form of a pouch formed of a flexible material, such as a foil. Tabs that form the terminals for the battery cells 132 can be connected to the electrodes (e.g., 134A, 134B) within the casing and extend out of the casing for electrical connection to other battery cells 132. Also, the tabs can be sealed where they pass through the cell casing.

[0075] In other embodiments, the battery cells can be prismatic cells or cylindrical cells. For example, an embodiment of a battery pack that includes cylindrical cells is shown in FIG. 3. The battery pack 330 can include a plurality of cylindrical battery cells 332 disposed within a housing 360. The cylindrical battery cells 332 can be arranged in rows that extend from one side of the housing to the other. The battery pack 330 can also include fluid conduits 342 of a first fluid circulation system 340 and fluid conduits 352 of a second fluid circulation system 350. Both the fluid conduits 342 of the first fluid circulation system 340 and the fluid conduits 352 of the second fluid circulation system 350 can also be disposed within the housing 360. Figure 3 The cylindrical battery cells 332 can be positioned within cavities in the battery pack 330 that form part of the first fluid circulation system 340. Thus, the fluid conduits 342 of the first fluid circulation system 340 can be formed around the cylindrical battery cells 332. As a result, each of the cylindrical battery cells can be surrounded by the first fluid 341 within the first fluid circulation system 340. As shown in FIG. 3, the fluid conduits 342 of the first fluid circulation system 340 can be formed around the cylindrical battery cells 332 on the left side of the battery pack 330 and the fluid conduits 352 of the second fluid circulation system 350 can be formed around the cylindrical battery cells 332 on the right side of the battery pack 330.

[0076] Figure 3 ​​In the illustrated embodiment, the fluid conduit 352 of the second fluid circulation system 350 can be disposed between the cavities that house the cylindrical battery cells 332. In some embodiments, the positioning of the cylindrical battery cells 332 of each row can be staggered such that the fluid conduit 342 of the first fluid circulation system 340 has a tortuous path. Such a configuration can help facilitate the flow of the first fluid 341 in the first fluid circulation system 340 around the cylindrical battery cells 332.

[0077] In embodiments of the battery system, the first fluid 141 within the first fluid circulation system 140 can be a dielectric. As such, the conductive portions of the battery cells 132, such as the terminals, can be in direct fluid communication with the first fluid 141 without compromising the performance of the battery cells 132. As used herein, the term dielectric includes a variety of dielectric substances known in the art and can be suitably used in the systems and methods described herein. For example, embodiments of the first fluid can include aliphatic compounds (e.g., C14-C50 alkyl compounds, C14-C50 alkenyl compounds, C14-C50 alkynyl compounds, polyolefins such as poly-alpha-olefins), aliphatic oxygenates (e.g., ketones, ethers, esters, or amides), aromatic compounds (e.g., dialkyl benzenes such as diethylbenzene, cyclohexylbenzene, 1-alkylnaphthalenes, 2-alkylnaphthalenes, dibenzyltoluene, and alkylated biphenyls), aromatic oxygenates (e.g., ketones, ethers, esters, or amides), silicones (e.g., silicone oils and silicates), halocarbons and hydrohaloethers, and any combination thereof. In some embodiments, the first fluid 141 can have a dielectric constant or relative permittivity of less than 6. Also, in some embodiments, the first fluid 141 can be a liquid dielectric having a mineral oil base. Other liquid dielectrics including synthetic fluids are also possible for use as the first fluid 141.

[0078] In some embodiments, the second fluid 151 within the second fluid circulation system 150 may be a different fluid from the first fluid 141 within the first fluid circulation system 140. For example, in some embodiments, the second fluid 151 within the second fluid circulation system 150 may be a heat exchange fluid having a higher thermal conductivity than the first fluid 141 in the first fluid circulation system 140. For example, the second fluid 151 may be an aqueous solution having a higher thermal conductivity than the first fluid 141. In some embodiments, the second fluid 151 may have a thermal conductivity at least 0.2 W / m K higher than the first fluid 141; for example, the second fluid 151 may have a thermal conductivity at least 0.4 W / m K higher than the first fluid 141. Using a second fluid 151 with a higher thermal conductivity than the first fluid 141 can allow the battery system to more effectively control the temperature of the battery cell 132. In other embodiments, the first fluid 141 and the second fluid 151 may be the same fluid. In such embodiments, the corresponding flow of the first fluid 141 and the second fluid 151 can facilitate thermal management without the difference in thermal conductivity.

[0079] In some embodiments, the fluid conduit 142 of the first fluid circulation system 140 is at least partially defined by the housing of the battery cell 132. For example, as Figure 1 As shown, the first fluid conduit 144 is defined by the housing of the first battery cell 134 on one side and the first conduit wall 146 on the other side. The portion of the boundary of the first fluid conduit 144 defined by the housing of the first battery cell 134 results in fluid contact between the first fluid 141 and the first battery cell 134, which facilitates heat transfer between the first battery cell 134 and the first fluid 141 within the first fluid conduit 144. In addition to the housing of the battery cell 132 and any conduit wall, the fluid conduit 142 may also be defined by the housing 160 of the battery pack 130 or by other components. In other embodiments, the fluid conduit 142 of the first fluid circulation system 140 may be defined by an annular conduit wall. For example, in some embodiments, the fluid conduit 142 of the first fluid circulation system 140 may be formed by an elongated annular conduit wall (such as a pipe). Similarly, the fluid conduit 152 of the second fluid circulation system 150 may also be defined by a conduit wall, the housing of the battery cell 132, the housing 160 of the battery pack 130, or by other components.

[0080] In some embodiments, the fluid conduits 142 of the first fluid circulation system 140 and the fluid conduits 152 of the second fluid circulation system 150 can be divided by a shared conduit wall. For example, a shared conduit wall 148 divides the first fluid conduit 144 of the first fluid circulation system 140 and the first fluid conduit 154 of the second fluid circulation system 150. Thus, the shared conduit wall 148 can be in fluid communication with the first fluid 141 in the first fluid conduit 144 of the first fluid circulation system 140 as a single piece, and also in fluid communication with the second fluid 151 in the first fluid conduit 154 of the second fluid circulation system 150. This shared conduit wall 148 reduces thermal resistance between the first fluid 141 in the first fluid conduit 144 of the first fluid circulation system 140 and the second fluid 151 in the first fluid conduit 154 of the second fluid circulation system 150, which facilitates heat transfer between the two fluid circulation systems 140, 150. In other embodiments, the fluid conduits 142, 152 of each of the first fluid circulation system 140 and the second fluid circulation system 150 can have their own conduit walls that are thermally coupled to one another.

[0081] In some embodiments, the fluid conduits 142, 152 can have a layered configuration between the battery cells 132. In some embodiments, a path between two battery cells 132 in the battery pack 130 can pass through multiple conduits in the layered configuration. For example, as shown in FIG. 1, a path between the first battery cell 134 and the second battery cell 136 passes through the first fluid conduit 144 of the first fluid circulation system 140, the first fluid conduit 154 of the second fluid circulation system 150, and the second fluid conduit 146 of the first fluid circulation system 140. Figure 1 In some embodiments, the fluid conduits 142, 152 can have a layered configuration between the battery cells 132. In some embodiments, a path between two battery cells 132 in the battery pack 130 can pass through multiple conduits in the layered configuration. For example, as shown in FIG. 1, a path between the first battery cell 134 and the second battery cell 136 passes through the first fluid conduit 144 of the first fluid circulation system 140, the first fluid conduit 154 of the second fluid circulation system 150, and the second fluid conduit 146 of the first fluid circulation system 140.

[0082] In other embodiments, the fluid conduits can be arranged in a layered configuration along the length of the battery cells. Such embodiments are shown in FIGS. 2-4. Figure 4The battery pack 430 can include a plurality of battery cells 432 disposed within the housing 460. The battery pack can also include electrical connections 462 disposed between the battery cells 432 on the exterior of the housing 460. The battery pack 430 can also include the fluid conduits 442 of the first fluid circulation system 440 and the fluid conduits 452 of the second fluid circulation system 450. Both the fluid conduits 442 of the first fluid circulation system 440 and the fluid conduits 452 of the second fluid circulation system 450 can also be disposed within the housing 460. The fluid conduits 442 of the first fluid circulation system 440 and the fluid conduits 452 of the second fluid circulation system 450 are arranged in a layered configuration along the length of each of the battery cells 432. As a result, both the fluid conduits 442 of the first fluid circulation system 440 and the fluid conduits 452 of the second fluid circulation system 450 are adjacent to each battery cell 432. This allows for a more compact configuration of the battery pack 430, as the distance between two adjacent battery cells 432 is the thickness of a single fluid conduit (i.e., either the fluid conduits 442 of the first fluid circulation system 440 or the fluid conduits 452 of the second fluid circulation system 450).

[0083] Similar to other illustrated embodiments, in some embodiments, the fluid conduits 452 of the second fluid circulation system 450 can each be surrounded by an annular conduit wall that isolates the second fluid 451 from the battery cells 432, while the fluid conduits 442 of the first fluid circulation system 440 are partially defined by the housing of the battery cells 432, such that the first fluid 441 is in fluid communication with the battery cells 432. In other embodiments, the fluid conduits 442, 452 of both fluid circulation systems 440, 450 can be formed by annular conduit walls.

[0084] In some embodiments, the flow through the fluid conduits is horizontal. For example, as illustrated by the directional arrows in FIG. 2, the flow through the fluid conduits 242 of the first fluid circulation system 240 and through the fluid conduits 252 of the second fluid circulation system 250 of the battery pack 230 can be horizontal. Likewise, as illustrated by the directional arrows in FIG. 4, the flow through the fluid conduits 442 of the first fluid circulation system 440 and through the fluid conduits 452 of the second fluid circulation system 450 of the battery pack 430 can also be horizontal. Figure 1 In some embodiments, the flow through the fluid conduits is horizontal. For example, as illustrated by the directional arrows in FIG. 2, the flow through the fluid conduits 242 of the first fluid circulation system 240 and through the fluid conduits 252 of the second fluid circulation system 250 of the battery pack 230 can be horizontal. Likewise, as illustrated by the directional arrows in FIG. 4, the flow through the fluid conduits 442 of the first fluid circulation system 440 and through the fluid conduits 452 of the second fluid circulation system 450 of the battery pack 430 can also be horizontal. Figure 3 In some embodiments, the flow through the fluid conduits is horizontal. For example, as illustrated by the directional arrows in FIG. 2, the flow through the fluid conduits 242 of the first fluid circulation system 240 and through the fluid conduits 252 of the second fluid circulation system 250 of the battery pack 230 can be horizontal. Likewise, as illustrated by the directional arrows in FIG. 4, the flow through the fluid conduits 442 of the first fluid circulation system 440 and through the fluid conduits 452 of the second fluid circulation system 450 of the battery pack 430 can also be horizontal.

[0085] In some embodiments, the battery pack 130 can include fire suppression features. For example, in some embodiments, the conduit wall between the first fluid circulation system and the second fluid circulation system can include a fire suppression passage configured to open when the conduit wall exceeds a predetermined temperature. For example, in some embodiments, the shared conduit wall 148 between the first fluid conduit 144 of the first fluid circulation system 140 and the first fluid conduit 154 of the second fluid circulation system 150 can include a normally closed fire suppression passage 149. At a predetermined temperature, the fire suppression passage 149 can open, allowing fluid to pass between the two fluid conduits 144, 154 in order to extinguish any fire that can be present. For example, the fire suppression passage 149 can include a mechanical valve configured to open at the predetermined temperature. Likewise, in some embodiments, the fire suppression passage 149 can be sealed with wax or another substance that melts at the predetermined temperature in order to open the fire suppression passage 149. Also, in some embodiments, the shared conduit wall 148 can be substantially thinner at the fire suppression passage 149 than in other areas, such that the section of the shared conduit wall 148 melts or otherwise opens at the predetermined temperature.

[0086] Figure 5 A battery system 500 is illustrated in accordance with embodiments of the present disclosure. The battery system 500 can be part of a device 590, such as a vehicle, and have a battery pack 530 that can be similar to any of the embodiments of the battery pack 130 described above. Figures 1-4 In particular, the battery pack 530 can include a plurality of battery cells 532 disposed within a housing 560. Each of the battery cells 532 can include an anode and a cathode disposed within a casing. The battery pack can also include electrical connections 564 between the battery cells 532. The battery pack 530 can also include a fluid conduit 542 of a first fluid circulation system 540 and a fluid conduit 552 of a second fluid circulation system 550. The fluid conduit 542 of the first fluid circulation system 540 can be at least partially defined by the casing of the battery cells 532, such that the first fluid 541 within the first fluid circulation system 540 is in direct contact, i.e., fluid contact, with the battery cells 532.

[0087] The first fluid circulation system 540 can also include a pump 502 configured to circulate the first fluid 541 through the first fluid circulation system 540. As stated above, the pump 502 can be any device that uses energy to move fluid. For example, the pump 502 can be formed by any actuator or mechanism that moves fluid, such as a rotary pump design, a piston pump design, or other pump designs.

[0088] The first fluid circulation system 540 can also include a heat exchanger 504 configured to allow heat to dissipate from the first fluid 541 within the first fluid circulation system. In some embodiments, the heat exchanger 504 can be within the device 590. For example, in cases where the device 590 is a vehicle, the heat exchanger 504 can be a radiator of the vehicle. In other embodiments, the heat exchanger 504 can be external to the device 590. For example, in some embodiments, the first fluid circulation system 540 can extend beyond the device 590 to an external source configured to remove heat from the first fluid 541 of the first fluid circulation system 540. Likewise, in some embodiments, the first fluid circulation system 540 and the second fluid circulation system 550 can be configured to transfer heat between the first fluid circulation system 540 and the second fluid circulation system 550 external to the battery pack 530.

[0089] The first fluid circulation system 540 can also include a valve 506 configured to regulate flow through the first fluid circulation system 540, including through the fluid conduits 542 within the battery pack 530. As described in greater detail below, the valve 506 and the pump 502 can be cooperatively operated to control the flow rate and pressure of the first fluid 541 in the first fluid circulation system 540. In some embodiments, the valve 506 can be coupled to a bypass control line 508 configured to bypass certain components of the first fluid circulation system 540. For example, as shown in FIG. 5B, the bypass control line 508 coupled to the valve 506 can be structured to bypass the heat exchanger 504. Figure 5 The valve 506 can be configured to regulate flow through the first fluid circulation system 540, including through the fluid conduits 542 within the battery pack 530. For example, in some embodiments, the valve 506 can be configured to regulate flow through the fluid conduits 542 of the battery pack 530. In other embodiments, the valve 506 can be configured to regulate flow through the fluid conduits 542 of the battery pack 530 and through the heat exchanger 504.

[0090] The battery system 500 can include a controller 580 configured to operate components of the first fluid circulation system 540, including the pump 502 and the valve 506. For example, the controller 580 can be configured to send a control signal to the pump 502, e.g., operable to increase the speed or power of the pump 502. Likewise, the controller 580 can be configured to send a control signal to the valve 506, e.g., operable to partially open, partially close, fully open, or fully close a gate of the valve 506. In embodiments of the battery system 500, the second fluid circulation system 550 can also include a pump and / or valve operable by a control signal from the controller 580 to circulate the second fluid 551 through the second fluid circulation system 550.

[0091] The controller 580 may include a non-transitory computer-readable medium having program instructions stored thereon for performing the methods of this disclosure. In some embodiments, the controller 580 may include a network interface 586, at least one memory 582, and / or at least one processor 584. Alternatively or in other embodiments, the controller 580 may include different types of computing devices operable to implement the program instructions. For example, in some embodiments, the controller may include a field-programmable gate array (FPGA) or an application-specific integrated circuit (ASIC) that performs processor operations.

[0092] Although Figure 5 As shown, the controller 580 of the battery system 500 may be physically located within the device 590, but in other embodiments, at least some portions of the controller 580 may be physically separated from the rest of the device 590. For example, in some embodiments, one or more portions of the controller 580 may be located remotely from the device 590 and communicate with the rest of the device via a network interface 586. Furthermore, in some embodiments, the controller 580 may be a client device, i.e., a device actively operated by a user, while in other embodiments, the controller 580 may be a server device, for example, a device that provides computing services to client devices. Additionally, other types of computing platforms are possible in embodiments of this disclosure.

[0093] The memory 582 is a type of memory available to a computer, such as random access memory (RAM), read-only memory (ROM), non-volatile memory (such as flash memory), solid-state drives, hard disk drives, optical storage devices, and / or magnetic storage devices.

[0094] The processor 584 of the controller 580 includes a computer processing element, such as a central processing unit (CPU), a digital signal processor (DSP), or a network processor. In some embodiments, the processor 584 may include register memory for temporarily storing instructions being executed and corresponding data, and / or cache memory for temporarily storing executed instructions. In some embodiments, as described herein, memory 582 stores program instructions executable by the processor 584 for implementing the methods and operations of this disclosure.

[0095] Network interface 586 provides a communication medium between controller 580 and other computing systems or devices, such as, but not limited to, digital and / or analog communication media. In some embodiments, the network interface may operate via a wireless connection (such as IEEE 802.11 or Bluetooth), while in other embodiments, network interface 586 may operate via a physical wired connection (such as an Ethernet connection). In still other embodiments, network interface 586 may use another protocol for communication.

[0096] In some embodiments, the controller 580 can be configured to operate the pump 502 and / or the valve 506 to adjust the pressure of the first fluid 541 in the first fluid circulation system 540. For example, the controller 580 can be configured to send a signal to the pump 502 to operate the pump at a higher power, and likewise, the controller 580 can be configured to send a signal to the valve 506 to partially close the valve 506. Thus, the volumetric flow through the first fluid circulation system 540 can be maintained or increased while also increasing the pressure of the first fluid 541 within the battery pack 530.

[0097] In some embodiments, the controller 580 is configured to send a control signal to the pump 502 to operate the pump 502 at an elevated pressure. For example, the controller 580 can operate the pump 502 to maintain a higher pressure in the first fluid circulation system 540 than the pressure maintained in the second fluid circulation system 550. By operating the pump 502 at an elevated pressure, the expansion of the battery cells 532 within the battery pack 530 can be regulated. Using the pressure of the first fluid 541 in the first fluid circulation system 540 to regulate the expansion of the battery cells 532 in the battery pack 530 allows for the battery cells 532 to be manufactured with thinner or lighter casing materials. Since the fluid pressure of the first fluid 541 of the first fluid circulation system 540 can help control the expansion of the battery cells 532, the casing walls of the battery cells 532 can be thinner. Thus, each battery cell 532 and the battery pack 530 as a whole can be lighter. For example, in some embodiments, the casing of the battery cells 532 can be a foil material that can have a material thickness in a range from 0.05 millimeters to 0.4 millimeters. Despite using thin foil materials, the battery system 500 can control the expansion of the battery cells 532 through the pressure of the first fluid 541 in the first fluid circulation system 540.

[0098] In some embodiments, the controller 580 can receive sensor values from various sensors and adapt the control signals sent to the pump 502 and / or the valve 506 based on the values from the sensors. For example, the controller 580 can receive pressure values from the pressure sensor 588 and use a feedback loop to send control signals to the pump 502 and / or the valve 506 based on the values received from the pressure sensor 588. Also, the controller 580 can receive values corresponding to the current flowing into or out of the battery pack 530 from the current meter 589 and adjust the control signals based on the values received from the current meter 589.

[0099] In some embodiments, the device 590 can be an electric, battery-powered vehicle, and the controller 580 can be configured to operate the pump 502 and / or the valve 506 based on an operating state of the vehicle. For example, during normal vehicle operation, the controller 580 can be configured to operate the pump 502 to circulate the first fluid 541 through the first fluid circulation system 540 in order to control the temperature of the battery cells 532 in the battery pack 530. Also, during normal vehicle operation, the controller 580 can be configured to maintain the valve 506 in an open position so that the first fluid 541 is normally circulated.

[0100] In some embodiments, during engine warm-up from a cold ambient temperature, the controller 580 can be configured, for example, to operate the pump 502 in order to circulate the first fluid 541 through the first fluid circulation system 540 in order to control the temperature of the battery cells 532 of the battery pack, and to operate the valve 506 so that the first fluid 541 passes through the bypass control line 508 in order to bypass the heat exchanger 504 and warm up more quickly.

[0101] Also, in some embodiments, during high operating loads of the vehicle, such as climbing a hill or moving at high speed, the controller 580 can be configured to partially close the valve 506 to create an elevated pressure in the first fluid circulation system 540, and to operate the pump 502 to circulate the first fluid 541 through the first fluid circulation system 540 in order to control the temperature of the battery cells 532 of the battery pack. Likewise, during charging of the battery cells 532, the controller 580 can again be configured to partially close the valve 506 to create an elevated pressure in the first fluid circulation system 540, and to operate the pump 502 to circulate the first fluid 541 through the first fluid circulation system 540 in order to control the temperature of the battery cells 532 of the battery pack. The elevated pressure in the first fluid circulation system 540 during charging or high loads can be higher than the pressure in the first fluid circulation system 540 during normal operating conditions.

[0102] Figure 6 A charging station 610 for use with a battery system 600 according to embodiments of the present disclosure is illustrated. The battery system 600 has a battery pack 630 that can include any of the features of the embodiments described above. For example, the battery pack 630 can include a plurality of battery cells 632, a first fluid circulation system 640 containing a first fluid 641, and a second fluid circulation system 650 containing a second fluid 651. As with the battery systems described previously, the first fluid circulation system 640 can include a plurality of fluid conduits 642, and the second fluid circulation system 650 can also include a plurality of fluid conduits 652.

[0103] The charging station 610 can be configured to provide an electrical charge to the battery system 600 as well as assist in thermal management of the battery cells 632. For example, the charging station 610 can include electrical terminals 612 configured to couple to electrical contacts 692 of the battery system 600. The electrical contacts 692 of the battery system 600 can be electrically connected to the battery cells 632 of the battery pack 630. As a result, the charging station 610 is configured to provide a charging current to the battery cells 632 of the battery pack 630 via the electrical terminals. The charging station 610 can also include fluid terminals 614 on a fluid line 616 configured to couple to a fluid coupling 694 of the battery system 600. The fluid coupling 694 can be in fluid communication with the second fluid circulation system 650. Both the fluid line 616 and the fluid coupling 694 can include a fluid supply path and a fluid return path. Thus, the charging station 610 is configured to circulate the second fluid 651 through the second fluid circulation system 650 and then receive the second fluid 651 that has been circulated through the second fluid circulation system 650.

[0104] To provide circulation of the second fluid 651 through the second fluid circulation system 650, the charging station 610 can include a pump 622 in fluid communication with the fluid line 616. Also, the charging station 610 can further include a heat exchanger 624 such that the charging station 610 is capable of delivering the second fluid 651 at a regulated temperature. In some embodiments, the heat exchanger 624 can be associated with a single charging station 610. In other embodiments, multiple charging stations can circulate the second fluid 651 through a large heat exchanger 624. Other components for controlling the pressure, temperature, and contents of the second fluid 651 can be included in the charging station 610. For example, the charging station 610 can include filters and monitors for assessing the quality of the fluid received from the vehicle 690.

[0105] In some embodiments, the electrical contacts 692 of the battery system 600 and the fluid coupling 694 of the battery system 600 can be disposed in a common plug housing 696. Likewise, the electrical terminals 612 and the fluid terminals 614 of the charging station 610 can also be disposed in a common plug housing 618. Thus, a user can be able to connect both the electrical components and the fluid components of the charging station 610 to the battery system 600 in a single operation. In some embodiments, the common plug housing 618 of the charging station can be disposed at an end of the fluid line 616, which can be in the form of a flexible tube.

[0106] Figure 7 An example embodiment of a method 700 of charging a power battery is shown. In some embodiments, the method 700 can be performed in conjunction with the battery system 600 and the charging station 610 described above. Figure 6The battery system 600 and the charging station 610 illustrated above are implemented in combination. As shown by block 702, the method 700 can involve connecting a fluid coupling of the battery system to a fluid terminal of the charging station. Also, as shown by block 704, the method 700 can involve receiving a charging current through the electrical contacts in the plurality of battery cells. As shown by block 706, the method 700 can further involve dissipating heat from the battery cells to a first fluid in a first fluid circulation system of the battery system. Also, as shown by block 708, the method 700 can further involve dissipating heat from the first fluid to a second fluid in a second fluid circulation system of the battery system. Still further, as shown by block 710, the method 700 can involve receiving a flow of the second fluid from the fluid terminal of the charging station through the fluid coupling, circulating the second fluid through the second fluid circulation system, and returning the second fluid to the fluid terminal of the charging station through the fluid coupling.

[0107] In some embodiments, the method can further include sending sensor data from the vehicle 690 to the charging station 620 to control the flow of the second fluid 651 through the second fluid circulation system 650. For example, the control system or controller 680 of the vehicle 690 can send data collected from sensors within the vehicle or the fluid circulation system. Such sensor data can include temperature information about the battery pack, pressure readings of the fluid in the first or second fluid circulation systems, and electrical readings from the battery cells, such as current, stored charge, and voltage. Based on the sensor data, the charging station 620 can adjust the flow of the second fluid 651 to the second fluid circulation system 650. For example, the charging station 620 can be configured to modify the speed of the pump 622 based on pressure readings in the second fluid circulation system 650.

[0108] The above detailed description describes various features and functions of the disclosed systems, devices, and methods with reference to the accompanying drawings. In the drawings, like reference numerals typically identify similar components, unless the context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments can be utilized, and other changes can be made, without departing from the scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein.

[0109] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope being indicated by the following claims.

Claims

1. A battery system comprising: a plurality of battery cells including a first battery cell and a second battery cell, each battery cell including a casing surrounding an anode and a cathode; a first fluid circulation system including a plurality of fluid conduits including a first fluid conduit adjacent the first battery cell and another first fluid conduit adjacent the second battery cell, wherein the first fluid circulation system is configured to circulate a first fluid through the battery system in a first direction; and a second fluid circulation system including a plurality of fluid conduits including a second fluid conduit adjacent the first fluid conduit of the first fluid circulation system and intervening between the first fluid conduit of the first fluid circulation system and the another first fluid conduit of the first fluid circulation system, wherein the second fluid circulation system is configured to circulate a second fluid through the battery system in a second direction opposite the first direction.

2. The battery system of claim 1, wherein, Each battery cell is a soft-pack battery cell.

3. The battery system of claim 1, wherein, The first fluid is a dielectric fluid.

4. The battery system of claim 1, wherein, The second fluid is a heat exchange fluid having a higher thermal conductivity than the first fluid.

5. The battery system of claim 1, wherein, The first fluid conduit of the first fluid circulation system is at least partially defined by the casing of the first battery cell such that fluid in the first fluid conduit is in fluid contact with the first battery cell.

6. The battery system of claim 1, wherein, The first fluid conduit of the first fluid circulation system and the second fluid conduit of the second fluid circulation system are separated by a common conduit wall.

7. The battery system of claim 1, wherein, A conduit wall between the first fluid circulation system and the second fluid circulation system includes a fire suppression passage configured to open when the conduit wall exceeds a predetermined temperature.

8. The battery system of claim 1, wherein, The first fluid circulation system is configured to circulate the first fluid serially through the plurality of fluid conduits of the first fluid circulation system.

9. The battery system of claim 5, further comprising a pump configured to circulate the first fluid through the first fluid circulation system.

10. The battery system of claim 9, further comprising a controller configured to operate the pump to maintain the first fluid at an elevated pressure.

11. The battery system of claim 10, wherein, The controller is configured to control the pump to adjust the pressure of the first fluid to control swelling of the plurality of battery cells.

12. The battery system of claim 10, wherein, The controller is configured to control a valve to adjust the pressure of the first fluid to control swelling of the plurality of battery cells.

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