Abstract:
A vehicle-battery system including a battery cell and a micro heat exchanger. The micro heat exchanger includes at least one fluid tube positioned in direct contact with the battery cell. The fluid tube comprises a heat-transfer tube section positioned between a fluid tube entrance and exit and in direct contact with the battery cell. The fluid tube is configured to receive a heat-transfer fluid, such a nanofluid, and channel the heat-transfer fluid through the heat-transfer tube section, to the fluid tube exit. The heat-transfer fluid is configured to cool or heat the battery cell when, in operation of the vehicle-battery system, the heat-transfer fluid is channeled through the heat-transfer tube section. The technology in various embodiments also includes a fluid modification device and a computerized controller for controlling the fluid modification device or other operations of the system such as pumping of the heat-transfer fluid.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates generally to systems and methods for managing transportation vehicle battery temperature and, more particularly, to vehicle battery thermal conditions using nanofluid, or other conventional heat transfer fluid—e.g., a coolant or refrigerant—passed through specially configured micro heat exchangers. 
       BACKGROUND 
       [0002]    Transportation vehicle batteries, such as lithium-ion batteries, operate optimally when kept within a target temperature range. Getting the battery quickly to, and keeping the battery within, the target range involves selective heating and cooling the battery, respectively. 
         [0003]    Conventional vehicle battery heating techniques include close-coupling the battery near an engine, or adjacent a pre-heated heating element. 
         [0004]    Conventional vehicle battery cooling techniques include positioning cooling fins on the battery. Another technique is pumping a cooling fluid, or coolant, from a holding tank to pass adjacent the battery. 
         [0005]    While helpful, conventional techniques have shortcomings including taking up an undesirably high amount of space, high cost in some cases, and not heating or cooling as efficiently or effectively as desired. 
       SUMMARY 
       [0006]    The present technology relates to systems and methods for managing vehicle battery temperature. The systems include one of a variety of micro heat exchangers. 
         [0007]    The micro heat exchangers are positioned at predetermined positions within and/or at a surface of the battery. 
         [0008]    The micro heat exchangers, in various embodiments, use a custom-made or pre-selected fluid, such as a nanofluid, or a microfluid having target characteristics. Target characteristics can include, for instance, super heating and/or super cooling, or an ability to absorb, carry, and/or deliver heat to or from the battery with much greater efficiency than conventional coolants or refrigerants, such as traditional automotive engine coolant. 
         [0009]    In various embodiments, the micro heat exchangers are used to cool vehicle batteries, and in some embodiments, the micro heat exchangers are used to heat batteries. 
         [0010]    Improved thermal management of vehicle batteries would have benefits including allowing design and use in vehicles of batteries having higher energy densities, allowing design and use of larger batteries, and facilitating higher performance from existing batteries. Benefits of the present technology also include space savings in the vehicle. 
         [0011]    Other aspects of the present technology will be in part apparent and in part pointed out hereinafter. 
     
    
     
         [0012]    DESCRIPTION OF THE DRAWINGS 
           [0013]      FIGS. 1-11  illustrate battery thermal-management systems according to various embodiments. 
           [0014]      FIG. 12  illustrates an example controller, or computing architecture, being part of or used with any of the systems described herein. 
       
    
    
       [0015]    The figures are not necessarily to scale and some features may be exaggerated or minimized, such as to show details of particular components. 
         [0016]    In some instances, well-known components, systems, materials or methods have not been described in detail in order to avoid obscuring the present disclosure. 
       DETAILED DESCRIPTION 
       [0017]    As required, detailed embodiments of the present disclosure are disclosed herein. The disclosed embodiments are merely examples that may be embodied in various and alternative forms, and combinations thereof. As used herein, for example, exemplary, and similar terms, refer expansively to embodiments that serve as an illustration, specimen, model or pattern. 
         [0018]    Specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure. 
         [0019]    While the present technology is described primarily herein in connection with transportation vehicles or modes of travel, and particularly with respect to automobiles, the technology is not limited to vehicles or modes of travel. The concepts can be used in a wide variety of applications, such as in connection with batteries of aircraft, marine craft, non-transportation machines, such as consumer goods and appliances, as examples. 
         [0020]    Any component shown or described as a single item in the figures can be replaced by multiple such items configured to perform functions provided in connection with the single item. Similarly, any multiple items shown or described can be replaced by a single item configured to perform the functions provided in connection with the multiple items. 
         [0021]    Directional references are provided herein mostly for ease of description and for simplified description of the example drawings, and the thermal-management systems described can be implemented in any of a wide variety of orientations. References herein indicating direction are not made in limiting senses. For example, references to upper, lower, top, bottom, or lateral, are not provided to limit the manner in which the technology of the present disclosure can be implemented. While an upper surface is referenced, for example, the referenced surface can, but need not be vertically upward, or atop, in a design, manufacturing, or operating reference frame. The surface can in various embodiments be aside or below other components of the system instead, for instance. 
         [0022]    I. General Overview of the Disclosure 
         [0023]    The present disclosure describes micro heat exchangers configured and arranged for use in managing temperature of transportation vehicle batteries. The micro heat exchangers, or at least thermal-transfer components thereof, are positioned at predetermined positions on one or more generally internal battery components and/or at an exterior surface of the battery, allowing for more design flexibility. Example thermal-transfer components include channels for cooling and/or heating. 
         [0024]    The micro heat exchanger, or at least the thermal-transfer components thereof, can be positioned, for instance, on tabs of the battery, on a bus bar of the battery, whether the bus bar is fully or partially solid or fully or partially hollow, or on one or more cells of the battery, such as on a surface and/or within the cell, for any form factor. 
         [0025]    The cooling systems according to various embodiments of the present technology are used on a relatively small scale, and can therefore be referred to as compact. Embodiments implemented fully or partially within a battery, or in interstices of the battery, can be referred to as being compact, being specially configured to be integrated for use within an especially small compartment or area of the battery. 
         [0026]    In one embodiment, the technology involves an integrated microelectromechanical (MEM) device being part of, or positioned in or on, a battery component. The device can include or be referred to as a micro heat exchanger (MHE). The term micro heat exchanger is used primarily herein. 
         [0027]    Micro heat exchangers in various embodiments use a custom-made or pre-selected fluid, such as a nanofluid, or a microfluid, having desired characteristics. A microfluid can be described as a fluid comprising micro-sized particles (including smaller, e.g., nano-sized), or simply fluids capable of effective movement through micro channels (including smaller). 
         [0028]    Characteristics of the fluid can include, for instance, super heating and/or super cooling, or an ability to absorb, carry, and/or deliver heat with much greater efficiency than conventional materials, such as traditional automotive engine coolant regarding cooling functions. 
         [0029]    The micro heat exchanger fluid can be distributed within the system in any of a wide variety of methods without departing from the scope of the present technology, including using any of valves, switches, and manifolds. 
         [0030]    The fluid can be moved within the micro heat exchanger actively, such as by pump, pull or vacuum, and/or what can be referred to as passively, or less active, such as by capillary action, convection, gravity, or heat-gradient currents, or a combination of any of these. Passive motivation can be controlled in any of various ways including, for example, by adjusting a surface tension of the heat exchange fluid and/or by other forces such as gravity. 
         [0031]    II.  FIG. 1   
         [0032]    Now turning to the figures, and more particularly the first figure,  FIG. 1  illustrates an example compact thermal-management system  100  according to the present technology. The thermal-management system  100  can also be referred to by other descriptive terminology, such as a thermal-control system, a temperature-control system, a temperature-management system, or the like. 
         [0033]    The thermal-management system  100  is configured for use with a battery cell  102 , such as a vehicle battery cell, to be used to power an electric or hybrid vehicle. The thermal-management system  100  comprises a micro heat exchanger configured and arranged for use in managing temperature of the battery cell  102 . 
         [0034]    Any of the features (systems, devices, sub-systems, components, etc.) described herein can be combined or separated in manufacturing or delivery, such as to be delivered and/or sold separately or together, such as in a kit. In one embodiment, the thermal-management system  100  and battery cell  102  are considered a part of a single apparatus. For instance, a company can manufacture the battery for receiving the thermal-management system  100 . The same or a different entity can provide the thermal-management system  100  with the specially designed battery, either as a kit for assembly and use, or already assembled, or provide the thermal-management system  100  separately from the specially designed battery. 
         [0035]    The example battery cell  102  in  FIG. 1  is a cylindrical cell, and can be a lithium-ion battery cell, such as an “18650” battery. As other example, embodiments of the thermal-management system  100  could have other sizes or styles, such as the “18350,” “18500,” or other rechargeable battery cell types. 
         [0036]    The thermal-management system  100  includes a micro heat exchanger fluid pathway, or channel  104 . While the channel  104  can be configured and arranged in or about the battery  102  in any of a variety of ways without departing from the scope of the present technology, in the embodiment illustrated, the fluid channel  104  extends generally through, or within, the battery cell  102 . Particularly, the fluid channel  104  passes generally through the battery cell  102  along an axial, center line of the battery cell  102 . 
         [0037]    The term micro heat exchanger (MHE) in various embodiments refers to the entire thermal management system  100 , or particularly to components of the thermal-management system  100  (e.g., fluid channels  104 ) positioned within and/or otherwise on or at the battery cell  102 , as just a few examples. According to one perspective, the micro heat exchanger of the thermal-management system  100  of  FIG. 1  is considered to include primarily the micro fluid channeling  104  within the thermal-management system  100 , which feature is called out generally and schematically by reference numeral  111 . 
         [0038]    While micro heat exchangers are called out by lining in the figures (e.g., MHE  111 ,  211 ,  311 , etc.), the indication does not necessarily require that the thermal-management system  100  include structure corresponding to the lining. The thermal-management system  100  in some embodiments include structure corresponding to the lines shown—e.g., a MHE body, or components connecting the fluid channels  104 —while in other embodiments the lining does not indicate an actual structure. 
         [0039]    The thermal-management system  100  can include any one or more of a wide variety of materials without departing from the scope of the present disclosure. Material must be configured to accommodate the fluid temperatures and any other effects to which the thermal-management system  100  may be exposed, such as thermal energy directly or indirectly from the battery  102 . As an example, the micro heat exchanger fluid channel  104  can include silicon, steel, copper, aluminum, etc. 
         [0040]    The micro heat exchanger fluid channel  104  can have any of a variety of shapes and sizes. As an example, in various embodiments the channel  104  is generally round, rounded (e.g., oval), square or otherwise rectangular in cross section, has more than one of these shapes at various places, or has any other suitable geometry. 
         [0041]    Regarding size, in various embodiments the micro heat exchanger fluid channel  104  has an outside diameter  105  of between about 1 μm and about 100 μm. While the micro heat exchanger fluid channel  104  can have other wall thicknesses, in one embodiment the channel  104 , at least within and/or adjacent a battery component(s) being cooled, has a wall thickness of between about 10 nm and about 1000 nm. 
         [0042]    One benefit of the channel  104  being relatively small and having sufficient wall thickness for robust operation is that the channel  104  will not collapse in use. 
         [0043]    The thermal-management system  100  further includes at least two fluid openings or orifices  106 ,  108 . The fluid orifices  106 ,  108  may be outfitted with input/output components (washers, ports, alignment parts, etc.; not shown in detail). At least one of the orifices  106 ,  108  can be used for fluid input and the other  108 ,  106  for output. In a contemplated embodiment, the thermal-management system  100  comprises a vent (e.g., air vent; not shown in detail), such as on the channel  104 , to facilitate movement of fluid into, though, and/or out of the fluid channel  104 , such as by relieving pressure build up that would otherwise impede fluid flow. 
         [0044]    The input and output components of this embodiment, as with all input and output components herein, can take any of a wide variety of forms without departing from the scope of the present technology. The components may include valves, ports, manifold arrangements, couplings, combinations of these, or similar features. 
         [0045]    Further regarding size of the micro heat exchanger fluid channel  104 , in one embodiment the channel  104  extends between the input  106  and the output  108  with a length dependent on the size of the battery. 
         [0046]    For cooling functions, the fluid channel  104  is filled with a cooled fluid, such as a chilled nanofluid. For heating functions, the fluid channel  104  is filled with a heated fluid, again such as a heated nanofluid. In a contemplated embodiment, the same fluid is used for heating and cooling, in turn, in the same micro heat exchanger for selectively heating (e.g., at cold-temperature starts for automobiles) and cooling (e.g., during extended electric vehicle use) a battery. 
         [0047]    The thermal-management fluid is referenced by number  109  in  FIG. 1  and its flow is indicated schematically by arrows leading into and out of the fluid channel  104 , and labeled by reference numerals  110 ,  112 . 
         [0048]    Any of a wide variety of fluids can be used with the present technology. Example fluids include nanofluids or microfluids engineered to have desired characteristics for use in the present micro heat exchanger. Example fluids are described further in the ‘Example Fluid Engineering and Types’ section (section XIV.), below. 
         [0049]    While nanofluid is described primarily as the applicable fluid  109  herein, any embodiment described can be implemented with another appropriate fluid configured to achieve the stated purposes and goals, such as a microfluid engineered to have desired features, including ability to be heated, super heated, chilled, or super chilled, for use in heating or cooling the battery according to the present technology. 
         [0050]    The chilled nanofluid  109  can be referred to as ‘cold nanofluid,’ or simply as a chilled or cold fluid to accommodate use of other appropriate fluids. Make-up, chilling, flow, and other features for the cold fluid are provided below. Similarly, heated nanofluid  109  can be referred to as ‘hot nanofluid,’ or simply as a heated or hot fluid. Make-up, heating, chilling, flow, and other features associated with the fluid are provided below. 
         [0051]    The nanofluid  109  (or other suitable fluid) can be cooled to any appropriate temperature for the implementation. Various considerations for determining a temperature or temperature range to cool the nanofluid  109  to or maintain it at can be considered. Example considerations include an amount and cost of energy required to obtain a target temperature. Another example consideration is a benefit or value of further cooling—e.g., avoiding chilling to or below a temperature below which there will be small or diminishing relative returns. 
         [0052]    In some implementations, the nanofluid  109  is cooled and controlled so as not to fall below a predetermined minimum temperature and/or so as not to rise above a predetermined maximum temperature—e.g. to stay within a pre-set, target range for the chilled fluid. 
         [0053]    In some embodiments, the nanofluid  109  is cooled to a temperature determined as a function of one or more factors. The factors can include a crystallization rate, or freezing point for a component of the thermal-management system  100  or the battery  102 . 
         [0054]    The thermal-management system  100  can include or be associated with heating equipment, to heat the nanofluid  109  as desired. The equipment can be a part of the reservoirs as mentioned, for example. In one embodiment, the heating equipment is controlled by circuitry, such as by the controller  120 . The reservoirs are described further below in connection with reference numeral  126 . 
         [0055]    The nanofluid  109  can be pre-heated to any appropriate temperature for the application. Various considerations for determining a temperature or temperature range to heat to or maintain, can be processed, as with cooling implementations. Example considerations for heating include an amount and cost of energy required to obtain a target temperature, and the value of further thermal adjustment, such as heating—e.g., avoiding heating the battery too long during freezing-weather start up, and to a temperature above which there will be small or diminishing relative returns. 
         [0056]    In some implementations, the nanofluid  109  is heated and controlled so as not to rise above a predetermined maximum temperature and/or so as not to fall below a predetermined minimum temperature—e.g. to stay within a pre-set, target range for the heated fluid. 
         [0057]    In some embodiments, the nanofluid  109  is heated to a temperature determined as a function of one or more factors. Factors can include, for example, a melting point of one or more components of the battery  102  or system  100 , or the melting point minus a factor such as a percentage of the melting point or a pre-set off-set temperature value. 
         [0058]    The nanofluid  109  (or other suitable fluid) can be moved through the thermal-management system  100  in any of a variety of ways including by one or more ways, which can be referred to as active and passive, or less active, as mentioned above. Example active means include pushing or pulling, such as by an upstream or downstream pump. Example passive, or less-active, means include using capillary action, convection, gravity, or heat-gradient currents, or a combination of any of these. 
         [0059]    Nanofluid  109  can be added to and/or moved through the system according to any appropriate timing. One goal of replacing, or replenishing the nanofluid  109  is maintaining a desired—e.g., predetermined—in-system fluid temperature and/or other fluid characteristics. Replenishing nanofluid could be used to maintain or keep a general desired or target temperature of the fluid  109  in the channel(s)  104 , for example. Other fluid characteristics that can be controlled, such as magnetic polarity, are described below. 
         [0060]    In various implementations, the nanofluid  109  is added and removed generally continuously to refresh the nanofluid  109  in the channel(s)  104  with fluid of the desired characteristic(s), for heating or cooling the battery  102 , to maintain the desired thermal-management system  100  temperature as desired—e.g., as predetermined. 
         [0061]    In various embodiments, some or all of the fluid control described is automated. The automated features may include, for instance, selectively heating or cooling the nanofluid  109 , and selectively causing the nanofluid  109  to flow into or out of the thermal-management system  100 , and at desired volumes, flow rates, temperature, and/or other characteristic(s) associated with the fluid. 
         [0062]    For embodiments in which flow of the fluid  109  results at least partially from capillary action, the flow can controlled at least in part by, for example, adjusting a surface tension of the heat exchange fluid  109 , such as a surface tension in the reservoir  126  described more below. 
         [0063]    As mentioned, the nanofluid  109  can also be modified in terms of temperature and in other ways, by automated machinery and/or personnel using tools. Example modifications include changing a magnetic polarity of the nanofluid  109 , changing the type or types of nanoparticles in the nanofluid  109 , or by changing a concentration of any of the types of nanoparticles in the fluid  109 , by adding or removing nanoparticles or base fluid to/from the nanofluid  109 . The modification can thus include changing an effective ratio of fluid components, such as of base fluid to nanoparticles. 
         [0064]    Example automated features are indicated schematically in  FIG. 1 , including a controller  120 . The controller  120  is configured and arranged for communication with other components such as a pump  122  and/or a fluid modification device (FMD)  124 . The configuration and arrangement of the controller  120  can include wired or wireless connection(s) to the pump  122  and/or FMD  124 . 
         [0065]    Fluid control can include monitoring of fluid characteristic, as mentioned, such as by closed-loop feedback. For instance, at least one sensor monitoring fluid temperature and/or other fluid characteristic (e.g., magnetic polarity, ratio of nanoparticles and base fluid) can be implemented at any of various portions of the arrangement. Example locations include any one or more of: an outlet of the FMD  124  (reference numeral  123   1 ) an inlet of the FMD, and inlet to a reservoir  126 , an outlet of the reservoir  126 , an inlet of the sleeve system  100  (reference numeral  123   2 ), and an outlet of the sleeve system  100 . The feedback loop can have benefits for the controller including advising whether the FMD  125  is performing as it is being instructed to perform, whether the controller  120  is sending proper signals or should send different signals—e.g., a signal to heat more or change fluid composition in a different manner. The feedback can also promote efficiency, such as when the sensor is at the FMD inlet, in that the controller  120  can consider a particularly what change(s) need to be made to the fluid at the FMD  124  to reach a target fluid characteristic(s) pre-determined at the controller  120  (e.g., target temperature and/or composition). 
         [0066]    The controller  120  is described further below, in section XIII., describing an example controller in the form of a computing system  1200  shown schematically in  FIG. 12 . 
         [0067]    The thermal-management system  100  can include or be connected to the reservoir  126 , holding the nanofluid  109  before and/or after it leaves the system channel(s)  104 . 
         [0068]    In some embodiments, the thermal-management system  100  includes or is connected to more than one reservoir  126 . The reservoir  126  can hold the same or different types of nanofluids  109 . The reservoirs  126  could also, whether holding the same or different types of nanofluid, maintain the nanofluids  109  at different temperatures. One of the reservoirs  126  could be a location at which chilled fluid is kept and/or fluid is chilled (at-reservoir chiller not shown in detail). One of the reservoirs  126  could be a location at which heated fluid is kept and/or fluid is heated (at-reservoir heater not shown in detail). 
         [0069]    The reservoir  122  is a location where the nanofluid  109  can be added, removed, or replaced in mass. The nanofluid  109  can be added, removed, or replaced in various manners, such as partially or in total, at one time or over a period of time. 
         [0070]    The nanofluid  109  can also be adjusted by the mentioned fluid-modification device (FMD)  124 . The FMD  124  can include can include a heater and a chiller being part of or connected to cold and hot reservoirs  126 , respectively. The FMD  124  can be integrated with, or as part of, the reservoir  126 , or vice versa. 
         [0071]    As mentioned, any component shown by a single item in the figures can be replaced by multiple such items, and any multiple items can be replaced by a single item. Here, for instance, though a single pump  122  is shown, the thermal-management system  100  can include or be connected to more than one pump  122 . 
         [0072]    Further regarding the FMD  124 , it can be configured to alter the nanofluid  109  in any of a variety of ways toward accomplishing goals of the present technology. As mentioned, the FMD  124  can include, e.g., a heater, or heating device, a chiller, or cooling device to heat or cool nanofluid  109  passing through the FMD  124  to a specified temperature before it is pumped or otherwise caused or allowed to flow into the channel(s)  104  of the thermal-management system  100 . 
         [0073]    In one embodiment, the FMD  124  includes a material-adjusting component for changing a make-up or characteristic of the nanofluid  109 , other than by only heating, or only cooling. The material-adjusting component can be configured to, for example, alter the nanofluid  109  in one or more ways, such as by changing a magnetic polarity of the nanofluid  109 , changing the type or types of nanoparticles in the nanofluid  109 , or by changing a concentration of any of the types of nanoparticles in the fluid  109 , by adding or removing nanoparticles or base fluid to/from the nanofluid  109 , to obtain desired qualities. 
         [0074]    In embodiments in which the FMD  124  illustrated represents more than one FMD  124 , or an FMD  124  with various functions (e.g., fluid heating and polarity change), the FMD  124  can include, for instance, one or both of a chiller and a material-adjusting component. 
         [0075]    The thermal-management system  100  includes any appropriate piping, valves, switches, and the like for directing the nanofluid  109  between the various components described in operation of the thermal-management system  100 . 
         [0076]    With continued reference to  FIG. 1 , the intake, outtakes  106 ,  108  and channel(s)  104  can vary in design. The intake, outtakes  106 ,  108  can be, for example, of any number, size, shape, and position within the thermal-management system  100  without departing from the scope of the disclosure 
         [0077]    A designer of the system can engineer the fluid channel  104  in any of a wide variety of shapes—e.g., patterns—to achieve desired goals, including, for instance, heat-distribution, heat-absorption, or heat-delivery goals within the thermal-management system  100 . 
         [0078]    In some embodiments, as shown in  FIGS. 4-11 , at least a portion of the fluid channel(s) is generally serpentine, or winding. A benefit of this arrangement is that more of the channeling is adjacent more of a relevant body or surface of the battery  102  needing temperature change. 
         [0079]    Other example distributions for the fluid channeling include cross-hatched pattern, a pin pattern, and a spiral or helicoid pattern. Other examples include manifold, single/multiple serpentines, parallel, and interdigitated. 
         [0080]    The thermal-management system  100  can include or be associated with chilling equipment, to cool the nanofluid  109  as desired. The equipment can be a separate device, such as the FMD  124  as shown in  FIG. 1 , or such device can be a part of the reservoir  126 , as mentioned, for example. In one embodiment, the chilling equipment is controlled by circuitry, such as by the controller  120 . 
         [0081]    As provided, the micro heat exchangers of the present technology can be configured for use in cooling and/or heating vehicle batteries. Keeping a battery operating as much as possible in its optimal temperature range has benefits, including greater battery energy densities, because a battery operated in its optimal temperature range delivers greater performance. 
         [0082]    Heating a battery is advantageous in situations such as cold-weather use of the battery. Heating a battery quickly at startup in cold weather, for example, improves battery performance, because batteries tend to otherwise lose performance when operated at very cold temperatures, e.g., ambient, outside environment temperatures of 0 degrees Celsius or less. 
         [0083]    Managing batteries in manners according to the present technology, using micro heat exchangers, has particular benefits including, by being a relatively smaller cooling and/or heating system, allowing for a more powerful, robust battery, by freeing up space for more battery cells in the battery pack. A result of the improved density is longer battery use on a charge and so longer range electric vehicles. Other benefits of the present technology are described below. 
         [0084]    III.  FIG. 2   
         [0085]      FIG. 2  illustrates a battery-cooling system  200  according to another example embodiment of the present disclosure. 
         [0086]    The embodiment of  FIG. 2  is similar to that of  FIG. 1 . The embodiment of  FIG. 2  comprises micro heat exchanger inputs and outputs  206 ,  208  positioned on generally the same side (e.g., top in the perspective of  FIG. 2 ) of the subject battery cell  202  by which the micro heat exchanger cooling fluid—e.g., nanofluid  109 —moves into  210  and out of  212  the apparatus. 
         [0087]    The micro heat exchanger channeling  204  thus includes a single channel  204  that changes directions, forming two parts  204   1 ,  204   2  or two channels  204   1 ,  204   2  connected. 
         [0088]    As for the embodiment of  FIG. 1 , the term micro heat exchanger can, in various embodiments associated with  FIG. 2  and others herein, refer to the entire thermal management system  200  or particularly to components of the system  200  (e.g., fluid channels  204 ) positioned within and/or otherwise on the battery  202 , as just examples. 
         [0089]    According to one perspective, among others, the micro heat exchanger of the system  200  of  FIG. 2  could be considered to include primarily the micro fluid channeling  204  within the system  200 , which feature is called out generally and schematically by reference numeral  211 . 
         [0090]    The embodiment of  FIG. 2  can otherwise be like the embodiments described above and below, and each similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0091]    IV.  FIG. 3   
         [0092]      FIG. 3  illustrates a battery thermal-management system  300  according to another example embodiment of the present disclosure. 
         [0093]    In the embodiment of  FIG. 4 , the micro heat exchanger fluid channel(s)  304  is positioned primarily on or at a surface  305  of the subject battery cell  302 . As mentioned, fluid channels can be partially or fully within the battery cell ( 302 ) and so, here, the MHE fluid channel(s)  304  can in contemplated embodiments be embedded partially or fully below the surface  305 . 
         [0094]    The micro heat exchanger fluid channel(s)  304  is distributed on or at the surface in any effective pattern. In the illustrated example, the micro heat exchanger fluid channel(s)  304  is distributed in generally a coiled, helicoid, spiral, curled, or winding, shape, wherein fluid flows in  306  to the cell  302  adjacent, or closer to, a periphery  307  of the surface  305 , and exits  308  the cell  302  adjacent or closer to a central portion or center  309  of the cell  302 . 
         [0095]    The term micro heat exchanger in some embodiments refers to the entire thermal management system  300  or particularly to components of the system  300  (e.g., fluid channels  304 ) positioned within and/or otherwise on the battery  302 , as just two examples. According to one perspective, among others, the micro heat exchanger of the system  300  of  FIG. 3  could be considered to include primarily the micro fluid channeling  304  within the system  300 , which feature is called out generally and schematically by reference numeral  311 . 
         [0096]    The embodiment of  FIG. 3  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0097]    V.  FIG. 4   
         [0098]      FIG. 4  illustrates a battery thermal-management system  400  according to another example embodiment of the present disclosure. 
         [0099]    The battery  402  can be a pouch-type battery. The battery  402  includes a pouch portion  403  and tabs  405 ,  407 . The pouch portion can be referred to by other terms, such as a pouch section or, simply, a pouch. 
         [0100]    The micro heat exchanger (e.g., reference numeral  411 ) in this embodiment includes a fluid channel  404  distributed through the pouch portion  403  of the battery  402 . 
         [0101]    The micro heat exchanger fluid channel(s)  404  is distributed through the pouch  403  in any effective manner, e.g., pattern. In the example shown, the channel  404  is distributed in a generally serpentine manner. While the distribution is shown in a generally two-dimensional manner, the distribution can include the channel  404  extending in various directions, such as into and out of the view of  FIG. 4 , along with back and further as it extends downward. 
         [0102]    And the micro heat exchanger fluid channel(s)  404  can be distributed within and/or outside of—e.g., on a surface of—the pouch  403 . The illustration of  FIG. 4  is configured to show this embodiment schematically as well in the alternative. 
         [0103]    Moreover, the micro heat exchanger fluid channel(s)  404  can be positioned generally in, at, and/or on any one or more of multiple sides or edges of the pouch  403 , such as in, at, or on a front and/or a back of the pouch  403 . The illustration of  FIG. 4  is configured to show this embodiment schematically, as well, in the alternative. 
         [0104]    The embodiment of  FIG. 4  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0105]    VI.  FIG. 5   
         [0106]      FIG. 5  illustrates a battery thermal-management system  500  according to another example embodiment of the present disclosure. The system  500  includes a micro heat exchanger  511  comprising at least one fluid channel  504 . 
         [0107]    The micro heat exchanger  511  of  FIG. 5  can be generally like the micro heat exchanger  411  described above in connection with  FIG. 4 . A difference between the embodiments is that the battery  502  on which the micro heat exchanger  511  is used in the case of  FIG. 5  has a different configuration than the battery  402  of  FIG. 4 . 
         [0108]    Notably, the tabs  505 ,  507  of the battery  502  of the embodiment of  FIG. 5  are positioned on opposing ends of the battery  502  in  FIG. 5  as opposed to the tabs  405 ,  407  being at a common end of the battery  402  in  FIG. 4 . 
         [0109]    The embodiment of  FIG. 5  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0110]    VII.  FIG. 6   
         [0111]      FIG. 6  illustrates a battery thermal-management system  600  according to another example embodiment of the present disclosure. 
         [0112]    The battery  602  of the embodiment of  FIG. 6  can be similar in ways to that of  FIG. 4 , also having tabs  605 ,  607  located at a common end of the battery  602 . 
         [0113]    The battery thermal-management system  600  comprises two micro heat exchangers  611   1 ,  611   2 , each positioned in, at, and/or on a respective one of the battery tabs  605 ,  607 . 
         [0114]    The micro heat exchanger fluid channels within the micro heat exchangers  611   1 ,  611   2  are distributed on and/or through the tabs  605 ,  607  in any effective manner, e.g., pattern. In the example shown, the channel is distributed in a generally serpentine manner. While the distribution is shown in a generally two-dimensional manner, the distribution can include the channel extending in various directions, such as into and out of the tab as the tabs are shown in  FIG. 6  (i.e., into and out of the paper, or view, of  FIG. 6 ). 
         [0115]    And the micro heat exchanger fluid channels of this embodiment can be distributed within and/or outside (e.g., on a surface) of the tabs  605 ,  607 , and the illustration of  FIG. 6  is configured to show this embodiment schematically as well in the alternative. 
         [0116]    Moreover, the micro heat exchanger fluid channel(s) can be positioned generally in, at, and/or on any one or more of multiple sides or edges of the tabs  605 ,  607 , such as in, at, or on a front and/or a back of the tabs  605 ,  607 . The illustration of  FIG. 6  is configured to show this embodiment schematically as well in the alternative. 
         [0117]    The embodiment of  FIG. 6  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0118]    VIII.  FIG. 7   
         [0119]      FIG. 7  illustrates a battery thermal-management system  700  according to another example embodiment of the present disclosure. 
         [0120]    From one perspective, the system  700  of  FIG. 7  can be considered generally as a combination of the embodiments of  FIGS. 5 and 6 . The battery  702  is similar in ways to that of the embodiment of  FIG. 5 , and the micro heat exchangers  711   1 ,  711   2  are similar to the embodiment of  FIG. 6 . 
         [0121]    Moreover, the fluid channels in the micro heat exchangers can be positioned generally in, at, and/or on any one or more of multiple sides or edges of the tabs  705 ,  707 , such as in, at, or on a front and/or a back of the tabs  705 ,  707 . 
         [0122]    The embodiment of  FIG. 7  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0123]    IX.  FIG. 8   
         [0124]      FIG. 8  illustrates a battery thermal-management system  800  according to another example embodiment of the present disclosure. 
         [0125]    The battery  802  of  FIG. 8  can be referred to as a prismatic battery  802 , or other terms such as a prismatic cell, a prismatic cell battery, or a prismatic can cell. 
         [0126]    The micro heat exchanger  811  of the embodiment of  FIG. 8  includes at least one fluid channel  804  distributed on, at, and/or within a surface of the battery  802 . 
         [0127]    The channel  804  is shown distributed adjacent tabs  805 ,  807  of the battery  802 . 
         [0128]    The micro heat exchanger fluid channel  804  within the micro heat exchanger  811  is distributed on and/or in the prismatic cell  802  in any effective manner, e.g., pattern. In the example shown, the channel  804  is in at least one portion distributed in a generally serpentine manner, and in other portions distributed in a manner suited for the space and component characteristics in the area. Again, goals for designing the channeling can include covering a large amount of the relevant areas and/or surfaces, e.g., as much as possible or practical under the circumstances, thereby promoting, or maximizing, heat transfer—e.g., selectively heating and/or cooling of the battery  802 . 
         [0129]    While distribution of the channeling  804  is shown in a generally two-dimensional manner, the distribution can include the channel extending in various directions, such as into and out of the battery  802 . 
         [0130]    And the micro heat exchanger fluid channels of this embodiment can be distributed within and/or outside (e.g., on a surface) of the battery  802 , and the illustration of  FIG. 8  is configured to show this embodiment schematically as well in the alternative. 
         [0131]    Moreover, the micro heat exchanger fluid channel(s)  804  can be positioned generally in, at, and/or on any one or more of multiple sides or edges of the battery  802 , such as in, at, or on a front and/or a back of the battery  802 . As an example of the micro heat exchanger being positioned on another surface,  FIG. 9  shows a system  900  according to an embodiment like that of  FIG. 8 , with a primary difference being that its micro heat exchanger  911  is positioned on a different surface (e.g., a back) of the battery  902  of  FIG. 9 . 
         [0132]    As provided, embodiments can be used together. Thus, for instance, the embodiment of  FIGS. 8, 9  can be combined, for multi-surface cooling by way of two separate micro heat exchangers, or a single combined micro heat exchanger, covering the two surfaces. 
         [0133]    As another example of the micro heat exchanger being positioned on another surface,  FIGS. 10 and 11  show system  1000 ,  1100  according to other embodiments, like that of  FIGS. 8, 9  with a primary difference being that their micro heat exchangers  1011 ,  1111  are positioned on a different surface (e.g., a bottom) of the battery  1002 ,  1102   
         [0134]    The embodiment of  FIG. 8  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0135]    X.  FIG. 9   
         [0136]      FIG. 9  illustrates a battery thermal-management system  900  according to another example embodiment of the present disclosure. 
         [0137]    As mentioned,  FIG. 9  shows a system  900  according to an embodiment like that of  FIG. 8 , with a primary difference being that its micro heat exchanger  911 , comprising micro heat exchanger fluid channeling  904 , is positioned on a different surface (e.g., a back) of the battery  902  of  FIG. 9 . 
         [0138]    As with the battery  802  of  FIG. 8 , the battery  902  of  FIG. 9  can be referred to as a prismatic battery, or other terms such as a prismatic cell, a prismatic cell battery, or a prismatic can cell. 
         [0139]    The embodiment of  FIG. 9  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0140]    XI.  FIG. 10   
         [0141]      FIG. 10  illustrates a battery thermal-management system  1000  according to another example embodiment of the present disclosure. 
         [0142]    As mentioned,  FIG. 10  shows a system  1000  according to an embodiment like that of  FIGS. 8, 9 , with a primary difference being that its micro heat exchanger  1011  is positioned on a different surface (e.g., a bottom) of the battery  1002  of  FIG. 10 . 
         [0143]    As with the battery  802  of  FIG. 8 , the battery  1002  of  FIG. 10  can be referred to as a prismatic battery, or other terms such as a prismatic cell, a prismatic cell battery, or a prismatic can cell. 
         [0144]    The channeling  1004  of this embodiment is shown distributed in a generally serpentine pattern, but can be distributed in any suitable manner, as mentioned.  FIG. 11  shows an example of alternative distribution of channeling at the same side (e.g., bottom) of the prismatic battery. 
         [0145]    The embodiment of  FIG. 10  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0146]    XII.  FIG. 11   
         [0147]      FIG. 11  illustrates a battery thermal-management system  1100  according to another example embodiment of the present disclosure. 
         [0148]    Like  FIG. 10 ,  FIG. 11  shows a system  1100  according to an embodiment like that of  FIGS. 8 and 9 , with a primary difference being that its micro heat exchanger  1111  is positioned on a different surface (e.g., a bottom) of the battery  1102  of  FIG. 11 . 
         [0149]    As with the battery  802  of  FIG. 8 , the battery  1102  of  FIG. 11  can be referred to as a prismatic battery, or other terms such as a prismatic cell, a prismatic cell battery, or a prismatic can cell. 
         [0150]    The channeling  1104  of this embodiment is shown distributed in a generally serpentine pattern, but can be distributed in any suitable manner, as mentioned.  FIG. 11  shows an example of alternative distribution of channeling at the same side (e.g., bottom) of the prismatic battery  1102 , as compared with the embodiment of  FIG. 10 . 
         [0151]    The embodiment of  FIG. 11  can otherwise be like the embodiments described above and below, and every similarity is not repeated here. Processes for controlling fluid temperature (e.g., heating and/or cooling), flow, non-temperature qualities, and timing of changes thereof, can be made according to any of the techniques described herein, including those described in connection with  FIG. 1 . 
         [0152]    XIII.  FIG. 12   
         [0153]      FIG. 12  illustrates an example controller  1200 , or computing architecture, being part of or used with any of the systems described herein. 
         [0154]      FIG. 12  shows an example controls system  1200 , such as a computing apparatus, or computer. The system  1200  can constitute the controls  120 , described above. 
         [0155]    The controls system  1200  includes a memory, or computer-readable medium  1202 , such as volatile medium, non-volatile medium, removable medium, and non-removable medium. The term computer-readable media and variants thereof, as used in the specification and claims, refer to tangible, non-transitory, storage media. 
         [0156]    In some embodiments, storage media includes volatile and/or non-volatile, removable, and/or non-removable media, such as, for example, random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), solid state memory or other memory technology, CD ROM, DVD, BLU-RAY, or other optical disk storage, magnetic tape, magnetic disk storage or other magnetic storage devices. 
         [0157]    The controls system  1200  also includes a computer processor  1204  connected or connectable to the computer-readable medium  1202  by way of a communication link  1206 , such as a computer bus. 
         [0158]    The computer-readable medium  1202  includes computer-executable code or instructions  1208 . The computer-executable instructions  1208  are executable by the processor  1204  to cause the processor, and thus the controller  1200 , to perform any combination of the functions described in the present disclosure. 
         [0159]    Example functions or operations described include controlling a temperature of nanofluid being introduced to the thermal-management system of any of the embodiments shown and described. Another example function is changing nanofluid composition in a pre-determined manner to expedite or otherwise effect as desired a heating or cooling process. Another example function includes controlling a flow or flow rate by which the nanofluid is caused to flow through any of the example thermal management systems described or shown. 
         [0160]    The code or instructions  1208  can be divided into modules to perform various tasks separately or in any combination. The module can be referred to by any convenient terminology. One module, configured with code to control one or more characteristics of the nanofluid using an FMD, could be referred to as a fluid-modification module, a fluid-characteristic-control module, or the like, for instance. 
         [0161]    The controller  1200  can also include a communications interface  1210 , such as a wired or wireless connection and supporting structure, such as a wireless transceiver. The communications interface  1210  facilitates communications between the controller  1200  and one or more external devices or systems  1212 , whether remote or local. 
         [0162]    The external devices  1212  can include, for instance, a remote server to which the controls system  1200  submits requests for data and/or from which the controls system  1200  receives updates or instructions. The external device  1212  could include a computer from which the control system  1200  receives operating parameters, such as a target temperature(s) or target composition(s) for the nanofluid(s), changes that need to be made to meet the target(s), other characteristics for or related to the fluid, cooling times, nanofluid flow rates or flow/switch timing, or another system characteristic. 
         [0163]    XIV. Example Fluid Engineering and Types 
         [0164]    The present technology in various embodiments includes or is used with any of a wide variety of thermal-management (e.g., heating and/or cooling) fluids, as mentioned. Example fluids include nanofluids and microfluids engineered to have desired characteristics for use in the micro heat exchangers disclosed herein. 
         [0165]    Nanofluids are engineered colloidal suspensions of nanometer-sized particles in a base fluid. The nanoparticles are typically metals, oxides, carbides, or carbon nanotubes. Example base fluids include water, ethylene glycol, and oil. 
         [0166]    Nanofluids are made to have unique properties, such as super-heating and/or super-cooling characteristics. A nanofluid could be engineered to have a thermal conductivity and convective-heat-transfer coefficient that are greatly enhanced over that of the base fluid, alone, for example. Engineering the fluid can include, for instance, magnetically polarizing the nanoparticles to obtain the desired qualities. 
         [0167]    While the nanofluid can include other nanoparticles without departing from the present disclosure, in various embodiments, the nanofluid includes one or a combination of silicon nanoparticles and metal-based nanoparticles. 
         [0168]    The nanofluid is for some implementations, surface functionalized. Surface functionalization of nanoparticles involves introducing functional groups (e.g., OH, COOH, polymer chains, etc.) to a surface of a nanoparticle. One characteristic of surface-functionalized nanofluids is increased particle dispersion in the nanofluid, which can be beneficial because increased thermal capacity, increased dispersion of thermal energy, and increased longevity of nanoparticle suspension. Another result is that conductive nanoparticles can be isolated using surface functionalization, which can be beneficial because of increased control over particle density in the fluid. 
         [0169]    As also mentioned, while nanofluids are discussed herein as the primary fluid for use in the present systems, other fluids able to perform as desired can be used. The fluids can include, e.g., microfluids, including micro-sized particles in a base fluid, or simply fluids capable of effective movement through micro channels, such as those of the micro channels of the present technology. 
         [0170]    XV. Select Benefits of the Present Technology 
         [0171]    Many of the benefits and advantages of the present technology are described herein above. The present section restates some of those and references some others. The benefits are provided by way of example, and are not exhaustive of the benefits of the present technology. 
         [0172]    A compact micro device can be positioned on and/or integrated inside a battery cell, including battery cells having conventional external sizing and at least general geometry. 
         [0173]    The present technology enables enhanced integrated battery cell cooling and/or heating by way of efficient thermal exchange during battery operation. 
         [0174]    Another advantage of using a micro heat exchanger is that channels of the exchanger will not collapse due at least in part to their relatively small size, or size and geometry. 
         [0175]    The present technology also improves, or allows for improved, battery energy density because a battery operated in its optimal temperature range delivers greater performance and a physically smaller heating and/or cooling system allows for more battery cells in the battery pack. A result of the improved density is longer battery use on a charge and in the automotive industry, for example, longer range electric vehicles. 
         [0176]    The present technology also simplifies battery assembly at the plant or manufacturing level because the heating and/or cooling system could be integrated into the cells themselves. Thereby, for instance, work and time can be saved by a manufacturing company in not having to install ancillary cooling or heating equipment for the battery, the notably lower amount of componentry provided by the present technology. 
         [0177]    The present technology also reduces vehicle or product weight associated with battery cooling and/or heating, and saves space. Relatively weighty and bulky conventional cooling components are not needed. 
         [0178]    XVI. Conclusion 
         [0179]    Various embodiments of the present disclosure are disclosed herein. The disclosed embodiments are merely examples that may be embodied in various and alternative forms, and combinations thereof. 
         [0180]    The above-described embodiments are merely exemplary illustrations of implementations set forth for a clear understanding of the principles of the disclosure. 
         [0181]    Variations, modifications, and combinations may be made to the above-described embodiments without departing from the scope of the claims. All such variations, modifications, and combinations are included herein by the scope of this disclosure and the following claims.