Abstract:
The present disclosure relates to apparatuses for conducting battery heat comprising an active material positioned between a first cover portion and second cover portion, each portion comprising a thermal conductive material and protection material connected to the thermal conductive material. Also included are systems for conducting heat includes a plurality of pouch cells each comprising an active material positioned between a first cover portion and second cover portion and a plurality of frames, at least one frame positioned between each of the plurality of pouch cells. Finally included are methods, for assembling a pouch cell structure for use in conducting battery heat, comprising constructing a pouch cell assembly by alternating a sequence of pouch cells and frames; positioning a first contact edge of each of pouch cell proximal to a first heat sink and a second contact edge of each pouch cells proximal to a second heat sink opposite the first contact edge; and connecting the first heat sink to the first contact edge of each of the plurality of pouch cells and connecting the second heat sink to the second contact edge of each of the plurality of pouch cells.

Description:
TECHNICAL FIELD 
       [0001]    The present technology relates to thermal conduction associated with vehicle batteries. More specifically, the present technology relates to accomplishing desired thermal conduction using concurrent pouch cell materials and extended pouch cell edges. 
       BACKGROUND 
       [0002]    Thermal energy (i.e., heat) can be dissipated or conducted using a pouch cell. A pouch cell is an electrode assembly containing electrode lead tabs that carry the positive and negative terminals to the outside of a sealed, flexible case or pouch. Pouch cells are lightweight and flexible in nature, due to an absence of metal casing, and are preferred to cylindrical cells for certain applications. 
         [0003]    Heat transfer using pouch cells have a wide array of application including grid energy storage, computer hardware, and vehicle batteries. 
         [0004]    Attempts have been made to reduce the weight of pouch cells without altering dissipation or conduction properties. One attempt has been to reduce the thickness of the pouch cell by reducing the number of layers within the electrode assembly. Although reducing the number of layers within the electrode assembly reduces the thickness of the pouch cell, the solution also reduces heat transfer through the pouch cell because heat transfer through an electrode assembly is directly related to the number of electrode layers. 
         [0005]    Additionally, this solution does not consider altering the cover material of the pouch cell to include a conductive layer that conduct heat, which will exist as a result of reducing the number of layers within the electrode assembly. 
         [0006]    According to another technique, more heat may be propagated by the pouch cell combined with a heat sink. When joining the pouch cell with the heat sink, sufficiency of thermal contact between the two is critical. Ways to ensure robust thermal contact between the pouch cell and the heat sink have included using thermal paste or conductive tape. Shortcomings of using this technique include unwanted additional mass of the paste or tape and possible weakening of the thermal contact by wearing away of the paste/tape over an extended time. 
       SUMMARY 
       [0007]    Given the aforementioned deficiencies, a need exists for systems and methods that efficiently enhance conduction of thermal energy using a pouch cell. 
         [0008]    The present disclosure relates to systems and methods for implementing a thermal conduction apparatus. The systems and methods satisfy the aforementioned need using conductive materials and protective materials within a pouch cell cover. The systems and methods also form robust thermal contact between the pouch cell and at least one heat sink. 
         [0009]    In operation, conduction of heat occurs through the edges of the pouch cell and the pouch cell cover including concurrent layered materials. Additionally, heat transfer occurs through the robust contact connecting the pouch cell to the at least one heat sink. 
         [0010]    Included in the present technology are apparatuses for conducting heat includes a pouch cell containing an active material positioned between a first cover portion and second cover portion, each portion comprising a thermal conductive material and protection material connected to the thermal conductive material. Additionally, the first cover portion is connected to the second cover portion at a first contact edge and at a second contact edge opposite the first contact edge. 
         [0011]    Also included is in the present technology are systems for conducting heat includes a plurality of pouch cells each comprising an active material positioned between a first cover portion and second cover portion and a plurality of frames, at least one frame positioned between each of the plurality of pouch cells. 
         [0012]    In some embodiments, the protection material may be located on each side of the thermal conductive material. 
         [0013]    In some embodiments, the first and second cover portions also contain barrier material adjacent to the protection material of both the first and second cover portions. Within some specific embodiments, the barrier material is located adjacent an outer surface exposed to atmosphere. 
         [0014]    In other embodiments, the first and second contact edges each contain a curvilinear section located at a juncture created by the first and second cover and the active material. In some embodiments, the curvilinear sections of the first and second contact edges connect respectively to a first and second heat sink. 
         [0015]    Finally, included in the present technology are methods, for assembling a pouch cell structure for use in conducting battery heat, comprising constructing a pouch cell assembly by alternating a sequence of pouch cells and frames; positioning a first contact edge of each of pouch cell proximal to a first heat sink and a second contact edge of each pouch cells proximal to a second heat sink opposite the first contact edge; and connecting the first heat sink to the first contact edge of each of the plurality of pouch cells and connecting the second heat sink to the second contact edge of each of the plurality of pouch cells. 
         [0016]    In these methods, at least one frame is located adjacent a first cover portion of a pouch cell and another frame is located adjacent a second cover portion of the same pouch cell. 
         [0017]    In some embodiments, the connecting further comprises compressing the pouch cell assembly through uniform contact perpendicular to the top of the pouch cell assembly. 
         [0018]    In other embodiments, the connecting further comprises bending the first contact edge and second contact edge of each pouch cell to a position perpendicular to the top of the pouch cell assembly. 
         [0019]    In other embodiments, the connecting further comprises adhering the first and second contact edges of each pouch cell respectively to a first buffer and a second buffer. 
         [0020]    In yet other embodiments, the connecting further comprises encircling a restraint around a perimeter formed by the pouch assembly and the first and second heat sinks located on either side of the pouch assembly. 
         [0021]    In yet other embodiments, the connecting further comprises contouring a contact surface on the first and second heat sinks, such that the distance to connect the respective first and second contact edges of each pouch cells and the respective first and second sinks is decreased. 
         [0022]    Other aspects of the present technology will be in part apparent and in part pointed out hereinafter. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  is a perspective view of a pouch cell with extended edge in accordance with an exemplary embodiment. 
           [0024]      FIG. 2  is a front view of another pouch cell having extended edges containing curvilinear sections. 
           [0025]      FIG. 3  is a cross-sectional view of another type of pouch cell. 
           [0026]      FIG. 4  is a side view of a plurality of pouch cells positioned to create contact with a heat sink. 
           [0027]      FIG. 5  is a perspective view of the plurality of pouch cells of  FIG. 4  after creating contact with a heat sink. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    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, illustrative, and similar terms, refer expansively to embodiments that serve as an illustration, specimen, model or pattern. 
         [0029]    Descriptions are to be considered broadly, within the spirit of the description. For example, references to connections between any two parts herein are intended to encompass the two parts being connected directly or indirectly to each other. As another example, a single component described herein, such as in connection with one or more functions, is to be interpreted to cover embodiments in which more than one component is used instead to perform the function(s). And vice versa—i.e., descriptions of multiple components herein in connection with one or more functions are to be interpreted to cover embodiments in which a single component performs the function(s). 
         [0030]    In some instances, well-known components, systems, materials or methods have not been described in detail in order to avoid obscuring the present disclosure. Specific structural and functional details disclosed herein are therefore 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 employ the present disclosure. 
         [0031]    While the present technology is described primarily in connection with a vehicle in the form of an automobile, it is contemplated that the technology can be implemented in connection with other vehicles, such as marine craft and air craft. 
         [0032]    While the technology is described primarily in connection with vehicle batteries, the technology is not limited to use with vehicle batteries. Other applications include cooling batteries used in grid energy storage and non-vehicle computers, as just two examples. 
       I. OVERVIEW OF THE POUCH CELL—FIGS.  1  AND  2   
       [0033]      FIG. 1  is a perspective view of a pouch cell  100 . The pouch cell  100  includes a pouch cell cover  110  and an active pouch cell material  115  (seen in callout of  FIG. 1 ). The pouch cell  100  also includes pouch cell contact edges  120 ,  130  and closure edges  140 ,  150 . 
         [0034]    The active material  115  of the pouch cell  100  is located behind the material of the cover  110 . The active material  115  is a conductive material configured and arranged to conduct heat from the battery—e.g., vehicle battery, via a set of electrode leads in connection with an active material. More specifically, the active material  115  is a cell assembly in which a positive electrode  180 , at least one separator  185  (e.g., an electrolyte), and a negative electrode  190  are stacked or wound to form the cell assembly. A positive electrode lead  160  and a negative electrode lead  170  are attached to the positive electrode  180  and the negative electrode  190 , respectively, and extend from the pouch closure edge  150  for connection with the vehicle battery. 
         [0035]    The active material  115  is coated with a current collector  195 , e.g., a thin Al or Cu plate made of aluminum, copper, or other conducing material, and attached to the electrode leads  160 ,  170 . Note that additional configurations of electrode cell assemblies known within the art may be practiced in accordance with the present technology. 
         [0036]    The active material  115  of the pouch cell may contain any material that conducts heat including but not limited to lithium cobalt oxide, lithium manganese dioxide, and/or lithium iron phosphate. 
         [0037]    The active material  115  of the pouch cell is commonly contained by an outer layer. More specifically, the active material  115  is in one embodiment contained by the cover  110  of the pouch cell  100 . 
         [0038]    The cover  110  of the pouch cell  100  in one embodiment includes a sheet (or multiple sheets) of material sealed on its side/sides—e.g., sealed at each of the four sides of the active material  115  of the pouch cell shown in  FIG. 1 . The function of the cover  110  is to protect and contain the active material  115  of the pouch cell  100 . Additionally, the cover  110  of the pouch cell  100  is intended to conduct heat from the vehicle battery. As such, the cover  110  in some embodiments comprises materials having both protecting properties as well as heat-conducting properties. 
         [0039]    As to not unnecessarily increase mass of the pouch cell  100 , the cover  110  is in one embodiment designed as a thin layer. For example, a layer of pouch cell cover  110  may be between approximately 1% and approximately 5% of an overall thickness of the pouch cell  100 . 
         [0040]    Further details concerning the structure and composition of the cover of the pouch cell are described below in association with  FIGS. 2 and 3 . 
         [0041]    In one embodiment, the contact edges  120 ,  130  and the closure edges  140 ,  150  are created by first placing the active material  115  between sheets of the pouch cell cover  110 . When the sheets of the cover  110  surround the active material  115 , the portions of the cover  110  not in contact with the active material  115  are cohesively connected (e.g., adhered) to create a seal around the active material  115 . The seal created by the layers of cover  110  in turn creates the four edges, i.e., contact edges  120 ,  130  and the closure edges  140 ,  150 . Closure edge  150  attaches a positive electrode lead  160  and a negative electrode lead,  170  to the active material  115  and secures in position the electrode leads  160 ,  170 . 
         [0042]    The closure edges  140 ,  150  seal the pouch cell  100  at the edges, containing the active material  115 . The contact edges  120 ,  130  similarly contain the active material  115  through sealing the pouch cell  100 . 
         [0043]    The contact edges  120 ,  130  function additionally to connect the pouch cell  100  with one or more heat sinks (shown  FIG. 2  and  FIG. 4 ). In the contemplated embodiment, the heat sinks are connected to pouch cell  100 , alternatively, in addition to, or by way of the contact edges  120 ,  130 . 
         [0044]    Adequate connection between the contact edges  120 ,  130  and the heat sinks is vital for conducting heat as desired from the vehicle battery to a cooling system contained within the heat sinks, which dissipate the heat transferred by the contact edges  120 , 130 . 
         [0045]    To promote the role of the contact edges  120 ,  130  to connect the pouch cell  100  to the heat sinks, the contact edges  120 ,  130  in one embodiment each has a greater width than widths of the closure edges  140 ,  150 , especially in embodiments in which the closure edges do not perform such an adhering function. More specifically, a contact edge width  125  is greater in width than the closure edge width  145 . 
         [0046]    Further details concerning structure of the pouch cell contact edges are described in association with  FIG. 2 . 
         [0047]      FIG. 2  is a side view of a pouch cell structure  200 . The pouch cell structure  200  is in turn part of a pouch cell assembly, shown in  FIG. 4 . The pouch cell structure  200  includes a pouch cell  220  and pouch cell edges. In some embodiments the pouch cell  220 , specifically an active material  224  and a pouch cell cover  228 , are similar in function and character to the pouch cell  100  and its components described in association with  FIG. 1 . In other embodiments, the pouch cell  220  includes additional features to enhance thermal contact between the pouch cell  220  and heat sinks  260 ,  270 . 
         [0048]    Similar to the pouch cell cover  110  described in  FIG. 1 , a pouch cell cover  228  in some embodiments includes sheets of material configured and arranged to encase and protect an active material  224  as well as to conduct heat from the vehicle battery. For these purposes, the cover  228  of the pouch cell  220  may include materials having protecting properties as well as heat-conducting properties. Further details concerning composition of the cover are described in association with  FIG. 3 . 
         [0049]    As described in  FIG. 1 , sheets of the cover  228  seal to create four edges along the perimeter of the pouch cell structure  200 , specifically two contact edges and two closure edges. The pouch cell structure  200 , illustrates contact edges  230 ,  240  as well as a closure edge  235 . The second closure edge (not illustrated) is located on the opposite side of the closure edge  235 . The closure edge  235  and the second closure edge exist to ensure the active material  224  is contained within the sheets of the cover  228 . In addition to containing the active material  224 , the contact edges  230 ,  240  connect the pouch cell structure  200  to a heat sink  260  and a heat sink  270  where heat is removed from the pouch cell structure  200 . 
         [0050]    The contact edges  230 ,  240  may include additional conductive material such as foil or sealing film to enhance the sheets of material within the cover  228 . These additional conductive materials may also be used to extend the contact edge  230 ,  240  to a width greater than the original width. 
         [0051]    The initial orientation of the contact edges  230 ,  240 , prior to the attachment of the heat sinks  260 ,  270 , is on a linear plane parallel to the linear plane of the closure edge  235 . However, when heat sinks  260 ,  270  are attached, the final orientation of the contact edges  230 ,  240  is on a plane that is perpendicular to the closure edge  235 . This perpendicular orientation will allow substantial contact with the heat sinks  260 ,  270 . Therefore, the width of the contact edges  230 ,  240 , such as the width  125  described in  FIG. 1 , should be such that the contact edges  230 ,  240  may fold to create a perpendicular orientation. For example, the contact edges  230 ,  240  may have a width approximately between 1 and 100 millimeters, depending on the pouch cell structure  200 . 
         [0052]    Properly connection of the contact edges  230 ,  240  to the heat sinks  260 ,  270 , is a critical purpose of the pouch cell structure  200 . Options to improve connection, and thus improve thermal contact, include among others: using frames to secure the position of the pouch cell  220 , curvilinear sections within the contact edges  230 ,  240 ; using buffers  280 ,  290  within the pouch cell structure  200 ; using a thermal adhesive  295  on the heat sinks  260 ,  270 . 
         [0053]    In some embodiments, the pouch cell  220  is secured by frames  210 ,  212 . The frame  210  may be positioned adjacent to a surface created by a sheet of the cover  228  on one side of the pouch cell  220 , and the frame  212  may be positioned adjacent to a surface created by a sheet of the cover  228  on the opposite side of the pouch cell  220 . Both frames  210 ,  212  serve to securely position the pouch cell  220 . In these embodiments, the frame  212  also serve as the point of contact between the contact edge  230  and heat sinks  260  as well as the point of contact between the contact edge  240  and the heat sink  270 . 
         [0054]    In certain embodiments, the frames  210 ,  212  may include a cutout within the frame molding that facilitates the automatic bending of the contact edges  230 ,  240 . Automatic bending creates an orientation of the contact edges  230 ,  240  that is in close proximity to a plane perpendicular to the linear plane of the closure edge  235 . When the contact edges  230 ,  240  have an orientation that near the desired perpendicular plane, connection to the heat sinks  260 ,  270  becomes easier. 
         [0055]    Further qualities and characteristics of support frames such as frames  210 ,  212  are well known in the art and will not be described in further detail. 
         [0056]    In some embodiments, the contact edges  230 ,  240  include curvilinear sections  235  and  245 , respectively. The curvilinear sections  235  and  245  create ridges within the contact edges  230 ,  240 . Ridges provide the contact edges  230 ,  240  the ability to stretch and bend during expansion and contraction of the pouch cell structure  200 . The ability of the curvilinear sections  235  and  245  to stretch and bend reduces the amount of stress experienced by the remaining portion the contact edges  230 ,  240 , which may prevent reduced thermal contact over time between the contact edges  230 ,  240  and the heat sinks  260 ,  270 . 
         [0057]    In some embodiments, the pouch cell structure  200  may include buffers  280 ,  290  between the frame and the contact edge. The buffers  280 ,  290  create uniform contact between the contact edges  230 ,  240  and the heat sinks  260 ,  270 . The buffers  280 ,  290  improve thermal contact by increasing contact pressure between the pouch cell structure  200  and the heat sinks  260 ,  270 . Since the thermal conductivity between the contact edge  230 ,  240  and the heat sinks  260 ,  270  depends on the contact pressure, higher and uniform contact pressure will increase the heat flow by increased heat conduction. 
         [0058]    The buffer  280  is located between the frame  212  and the contact edge  230 , and improves contact between the heat sink  260  and the contact edge  230 . Similarly, the buffer  290  is located between frame  212  and the contact edge  240  and creates improved contact between the heat sink  270  and the contact edge  240 . The buffers  280 ,  290  allow a uniform contact to be created between the contact edges  230 ,  240  and their respective heat sinks  260 ,  270 . The buffers  280 ,  290  also ensure adherence between contact edges  230 ,  240 , and their respective heat sinks  260 ,  270  to improve the heat transfer from the pouch cell structure  200  to the heat sinks  260 ,  270 . Contact buffers, such as the buffers  280 ,  290 , may be made of any insulating material such as rubber, silicone, or other polymers known in the art. 
         [0059]    In addition to curvilinear sections and buffers, the heat sinks  260 ,  270  may include a thermal adhesive  295  to improve contact with the pouch cell structure  200 . The thermal adhesive  295  would be applied to the surface of the heat sinks  260 ,  270  that are connected to the contact edges  230 ,  240 , e.g., contact surfaces  268  and  278  respectively. Thermal adhesives such as thermal paste/epoxy or conductive tape are used throughout the art to improve contact and heat transfer between items. 
         [0060]    Other embodiments can include a mechanical means of attaching the contact edges  230 ,  240  to the heat sinks  260 ,  270 . The mechanical means can be used for independent attachment or in conjunction with the thermal adhesive  295 . Mechanical means can include but are not limited to clips, such as wire-form or flat spring, spacers, or push pins. 
       II. POUCH CELL COMPOSITION—FIG.  3   
       [0061]      FIG. 3  is a cross sectional view of the cover material included in a cover assembly  300 . The cover assembly  300  includes successive layers of conductive material to conduct heat as well as protection material to shield the conductive material. The cover assembly  300  has an inner surface  360 , which is adjacent to an active material  115  (shown in the call out of  FIG. 1 ), and an outer surface  370 , which is adjacent to the atmosphere, e.g., air between one pouch cell and the next pouch cell within a multi pouch cell assembly, as described in  FIG. 4 . 
         [0062]    The cover assembly  300  includes a conductive layer  320 , which provides additional conduction as heat flows from the active material to the atmosphere. A first conduction occurs within the active material. As heat flows through the inner surface  360 , to the cover material assembly  300 , a second conduction of heat occurs due to the conductive layer  320 . Finally, heat is dissipated when it is delivered to a heat sink (not shown in  FIG. 3 ). 
         [0063]    For maximum heat distribution a single conductive layer is suggested, however, multiple conductive layers may be used to achieve the same rate of heat distribution. 
         [0064]    The conductive layer  320  may have a thermal conductivity (K) approximately between 200 W/m/K and 500 W/m/K. For example, the conductive material may include materials such as but not limited to aluminum (K≈200 W/m/K), copper (K≈300 W/m/K), graphite (K≈400 W/m/K). Additional material properties such as heat capacity, thermal conductivity, and thermal expansion may be used in selecting a conductive material. 
         [0065]    The thickness of the conductive layer  320  is typically inversely proportional to the thermal properties of the conductive material. More specifically, as the thermal conductivity coefficient increases, the required thickness of the conductive layer  320  decreases. Therefore, the thickness of the conductive layer  320  may vary depending on the conductive material used. 
         [0066]    The thickness of the conductive layer  320  should be such that efficient heat conduction occurs. This heat conduction can be measured through the change in temperature (ΔT) or other quantitative factor. For example, when striving for a ΔT of 5° C., if aluminum is the conductive material, the thickness of the conductive material may be between 30 microns and 50 microns. However, if copper is the conductive material in the same scenario, the thickness of the conductive material may only need to be between 20 and 40 microns. As the desired ΔT changes for different applications, so does the thickness of the conductive layer  320 . 
         [0067]    In addition to the conductive layer  320 , the cover material assembly  300  includes protection layers  310  and  330 . The protection layers  310  and  330  are connected to either side of the conductive layer  320  through a bonding layer  340 . The bonding layer  340  can be any means of bonding that is known in the art such as but not limited to thermoset polymers, thermoplastic material, solvent-cast adhesive, or glue. In certain embodiments, the bonding layer  340  of the protection layers  310  and  330  to the conductive layer  320  may occur through heat fusion. 
         [0068]    The protection layers  310  and  330  may be made of the same material or differing materials. Materials for the protection layers  310  and  320  may include, but are not limited to, polypropylene (PP), polyvinyl chloride (PVC), high density polyethylene (HDPE), polyamide (PA) nylon, or other similar materials. 
         [0069]    The thickness of the protection layers  310 ,  330  may be dependent on the material used. However, the protection layer  310  may likely have a greater thickness than the protection layer  330  due to the fact that the protection layer  310  is directly adjacent to the inner surface  360 , which receives heat transfer from the active material of the pouch cell. 
         [0070]    As an example, if the conductive layer  320  has a thickness of 50 microns, the protection layer  310  would be approximately between 100 and 150 microns. Additionally, the protection layer  330  would be approximately between 25 and 75 microns. 
         [0071]    In certain embodiments, the cover material assembly  300  may include a barrier layer  350 . The barrier layer  350  would serve as additional protection by preventing penetration of the pouch cell structure. The barrier layer  350  would separate the protection layer  330  from the outer surface  370 . Since the barrier layer  350  serves as a blockade, the thickness of the barrier layer  350  would be likely be less than the conductive layer  320 . The barrier layer  350  may be made from materials including but not limited polyethylene terephthalate (PET) and Polybutylene terephthalate (PBT). 
       III. POUCH CELL ASSEMBLY—FIGS.  4  AND  5   
       [0072]      FIG. 4  is a side view of a pouch cell assembly  400  containing multiple pouch cell structures. The pouch cell assembly  400  includes a plurality of frames and a plurality of pouch cell structures. Included in the plurality of pouch cell structures is a pouch cell structure  420 , which includes contact edges  430 ,  440 . The contact edges  430 ,  440  connect to heat sinks  460 ,  470 , respectively. Similarly, a pouch cell structure  422  includes contact edges  432  and  442 , which connect to heat sinks  460 ,  470  respectively. The same pouch cell structure exists for all pouch cells within the pouch cell assembly  400 . 
         [0073]    Options to improve connection and thermal contact are similar to the options discussed in association with  FIG. 2 . These options include the use of frames; the use of curvilinear sections (not shown, see reference numerals  235 ,  245  in  FIG. 2 ) within the contact edges; the use of buffers (not shown, see reference numerals  280 ,  290  in  FIG. 2 ); the use of thermal adhesive on the heat sinks (not shown, see reference numeral  295  in  FIG. 2 ). Each pouch cell may be secured by frames located on either side of the surfaces created by the pouch cells  420 ,  422 , etc. The frames serve to position the pouch cells and serve as a point of contact between the contact edges  430 ,  432 , etc. and heat sink  460  and the contact edges and  440 ,  442 , etc. and the heat sink  470 . 
         [0074]    The contact edges  430 ,  432 , etc. and  440 ,  442 , etc. may include curvilinear sections to allow for the expansion and contraction of pouch cell structure  200 . 
         [0075]    The buffers may be used to create uniform contact between the contact edges, e.g.,  430 ,  440 , and the heat sinks  460 ,  470  and would be located between a frame and a contact edge. Note that buffers may be used on all frames regardless of proximity to the contact edges. For example, a buffer would be located between frame  410  and the contact edge  430 , and another buffer would be located between the frame  410  and the contact edge  440 . For example, buffers may be located between frame  414  and the contact edges  432 ,  442 . Additionally, buffers may also be located on frame  412  to create additional contact surface area for the contact edges  430 ,  440 . 
         [0076]    The thermal adhesive may be the similar to the thermal adhesive  295  discussed in association with  FIG. 2 . The thermal adhesive would be applied to the surface of the heat sinks  460 ,  470  that are connected to the contact surfaces  468 ,  478 . Thermal adhesives such as thermal paste/epoxy or conductive tape are used throughout the art to improve contact and heat transfer between items. 
         [0077]    In some embodiments may include a mechanical means (not shown) of attaching the heat sinks  460 ,  470  to the pouch cell assembly  400 . The mechanical means can be used for independent attachment or in conjunction with an adhesive, e.g., the thermal adhesive  295 . Mechanical means can include but are not limited to clips, such as wire-form or flat spring, spacers, or push pins. 
         [0078]      FIG. 5  is a perspective view of the pouch cell assembly  400  after it has been connected to the heat sinks  460  and  470 . 
         [0079]    Options to improve connection and thermal contact are similar to the options discussed in association with  FIGS. 2 and 4 . Additionally, as seen in  FIG. 5 , thermal connection may be improved through encircling a restraint  480  around the perimeter of the pouch cell assembly  400 , or creating contoured heat sinks. 
         [0080]    The restraint  480  may be used to increase connection between each of the pouch edges within the pouch cell assembly  400  and the heat sinks  460 ,  470 . The restraint  480  would wrap around the perimeter of the heat sinks  460 ,  470  with the pouch cell assembly  400  inserted therebetween, creating points of contact with the exterior surface  462  on the heat sink  460  and the exterior surface  472  on the heat sink  470 . The restraint  480  may be any non-conducting material used to secure the overall pouch cell assembly  400  including but not limited to belts, straps, or cords. 
         [0081]    The contoured heat sink would include a convex surface to improve thermal contact during attachment of the heat sinks  460 ,  470  to the contact edges  430 ,  440 . The convex section would be along the contact surfaces  468  and  478 . 
         [0082]    In other embodiments, the exterior surfaces  462 ,  472  may also be contoured in embodiments that include a restraint  480 . Contoured heat sink embodiments may also include an insert  490  to create contact between the restraint  480  and the heat sink exterior surfaces  462  and  472 . The contoured heat sink would secure the contact surfaces  468 ,  478  to each of the contact edges included within the pouch cell assembly  400 . 
       IV. CONCLUSION 
       [0083]    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. 
         [0084]    The law does not require and it is economically prohibitive to illustrate and teach every possible embodiment of the present technology. Hence, the above-described embodiments are merely exemplary illustrations of implementations set forth for a clear understanding of the principles of the disclosure. 
         [0085]    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.