Patent Publication Number: US-2013230760-A1

Title: Battery module

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates to a battery module, and more particularly to a battery module with a liquid cold heat-dissipating mechanism. 
     BACKGROUND ART OF THE INVENTION 
     Gasoline-powered vehicles are widely used for transportation and become indispensible to our daily lives. With rapid development of the related technologies, mass production of gasoline-powered vehicles brings convenience to the human beings. However, during operations of the gasoline-powered vehicles, the burning of the gasoline may cause air pollution problem and serious environmental problem. In addition, the depletion of the gasoline may lead to global economic crisis. 
     For protecting the environment, the manufacturers of vehicles are devoted to the development and research of low pollution vehicles. Consequently, there are growing demands on clean and renewable energy. Among various kinds of new energy vehicles, electric vehicles (EV) are more advantageous because of the well-established technologies. In addition, since the power net is widespread over the world, it is convenient to acquire the stable electric energy. As a consequence, electric vehicles (EV) and hybrid electric vehicles (PHEV) are more important in the development of new energy vehicles. 
     Generally, the electric vehicle or the plug-in hybrid electric vehicle has a built-in chargeable battery as a stable energy source for providing electric energy to the control circuit or the mechanical power devices of the vehicle. In a case that the electric energy stored in the chargeable battery is exhausted, the chargeable battery is usually charged by a charging system. 
     Generally, during operations of the chargeable battery, a large amount of heat is generated. If the heat is not effectively dissipated away, the performance of the chargeable battery is deteriorated, and the use life of the chargeable battery is shortened. 
       FIG. 1A  is a schematic exploded view illustrating a conventional battery module. The conventional battery module  1  is disclosed in for example US Patent No. 2010/0092849. The conventional battery module  1  comprises an upper casing  10 , a lower casing  10 , and a plurality of intermediate trays  11 . The upper casing  10 , the lower casing  10  and the plural intermediate trays  11  collectively define a plurality of grooves  13 . The plural grooves  13  are used for accommodating plural battery cells  12 . In addition, each battery cell  12  has two terminals  120 . Moreover, the plural intermediate trays  11  are stacked on the lower casing  10 , and the upper casing  10  is stacked on the plural intermediate trays  11 . As a consequence, a multilayered battery module  1  is fabricated. 
       FIG. 1B  is a schematic cross-sectional view illustrating the battery module of  FIG. 1A . As shown in  FIGS. 1A and 1B , the battery module  1  comprises a plurality of battery cells  12 , which are arranged in a stacked form and disposed between the upper casing  10  and the lower casing  10 . Moreover, each of the upper casing  10  and the lower casing  10  has a plurality of openings  100 , and each of the plural intermediate trays  11  also has a plurality of openings  110 . After the upper casing  10 , the plural intermediate trays  11 , the lower casing  10  and the battery cells  12  are combined together to form the battery module  1 , as shown in  FIG. 1B , a vacant space  14  is formed within the battery module  1 . The vacant space  14  is served as an airflow channel for allowing the airflow to go through. In a case that an active heat-dissipating device such as a fan (not shown) is employed, the heat generated by the battery cells  12  may be dissipated away through the vacant space  14 . However, the efficiency of removing the heat from the battery cells  12  or the battery module  1  by the airflow is usually unsatisfied. 
     From the above discussions, the plural battery cells  12  are arranged between the upper casing  10  and the adjacent intermediate tray  11 , between every two adjacent intermediate trays  11  and between the lower casing  10  and the adjacent intermediate tray  11 . If one of the upper casing  10 , the intermediate trays  11  and the lower casing  10  is slid or shifted in response to an external force, the soldering materials on the battery cells  12  and their terminals  120  are possibly deviated. Under this circumstance, the reliability of the soldering materials at the terminals  120  will be impaired. 
     SUMMARY OF THE INVENTION 
     The present invention provides a battery module with honeycomb-shaped battery brackets for accommodating a plurality of battery cells. Moreover, after the battery cells are accommodated within the battery brackets, the battery cells can be securely fixed by a plurality of thermal pads. Consequently, the possibility of vibrating or rotating the battery cells will be minimized. 
     The present invention also provides a battery module with a liquid cold heat-dissipating mechanism for removing the heat from plural battery cells. Consequently, the battery module has enhanced heat-dissipating efficiency. 
     In accordance with an aspect of the present invention, there is provided a battery module. The battery module includes a first battery bracket, a second battery bracket, and a liquid cold heat-dissipating mechanism. The first battery bracket and the second battery bracket are stacked on each other. Each of the first battery bracket and the second battery bracket includes a plurality of hollow portions for accommodating a plurality of battery cells. The liquid cold heat-dissipating mechanism is used for removing heat from the plural battery cells by using a cooling liquid. The liquid cold heat-dissipating mechanism includes an input channel, an output channel, a first flow-channel plate, at least one first connecting member, and at least one second connecting member. The first flow-channel plate is arranged between the first battery bracket and the second battery bracket and includes a first flow channel. The at least one first connecting member is connected with the input channel and a first end of the first flow-channel plate. The at least one second connecting member is connected with a second end of the first flow-channel plate and the output channel. After the cooling liquid is introduced into the input channel, the cooling liquid is sequentially transferred through the first end of the first flow-channel plate, the first flow channel, the second end of the first flow-channel plate and the second connecting member, and discharged from the output channel. 
     The above contents of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a schematic exploded view illustrating the conventional battery module; 
         FIG. 1B  is a schematic cross-sectional view illustrating a battery module of  FIG. 1A ; 
         FIG. 2  is a schematic exploded view illustrating a battery module according to a first embodiment of the present invention; 
         FIG. 3  is a schematic view illustrating the combination of the first battery bracket and the second battery bracket of the battery module according to the first embodiment of the present invention; 
         FIG. 4  schematically illustrates a perspective view of a first flow-channel plate of the battery module of  FIG. 2  and a cutaway view of the first flow-channel plate; and 
         FIG. 5  is a schematic exploded view illustrating a battery module according to a second embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention will now be described more specifically with reference to the following embodiments. It is to be noted that the following descriptions of preferred embodiments of this invention are presented herein for purpose of illustration and description only. It is not intended to be exhaustive or to be limited to the precise form disclosed. 
       FIG. 2  is a schematic exploded view illustrating a battery module according to a first embodiment of the present invention. As shown in  FIG. 2 , the battery module  2  comprises a plurality of battery brackets  20  and a liquid cold heat-dissipating mechanism  24 . In this embodiment, the plural battery brackets  20  comprise a first battery bracket  20   a  and a second battery bracket  20   b , which are stacked on each other. Moreover, each of the first battery bracket  20   a  and the second battery bracket  20   b  comprises a plurality of hollow portions  200  for accommodating a plurality of battery cells  26 . 
     The liquid cold heat-dissipating mechanism  24  utilizes a cooling liquid to remove the heat from plural battery cells  26 , which are arranged between the first battery bracket  20   a  and the second battery bracket  20   b . In this embodiment, the liquid cold heat-dissipating mechanism  24  comprises an input channel  271 , an output channel  272 , a first flow-channel plate  21 , a first connecting member  221 , and a second connecting member  222 . The first connecting member  221  and the second connecting member  222  are located at two opposite sides of the first flow-channel plate  21 . In addition, a first junction channel  221   a  and a second junction channel  222   a  are disposed within the first connecting member  221  and the second connecting member  222 , respectively. The first junction channel  221   a  of the first connecting member  221  is in fluid communication with the input channel  271 . The second junction channel  222   a  of the second connecting member  222  is in fluid communication with the output channel  272 . 
     In this embodiment, the first battery bracket  20   a  and the second battery bracket  20   b  are stacked on each other, and the first flow-channel plate  21  is arranged between the first battery bracket  20   a  and the second battery bracket  20   b . Moreover, the first flow-channel plate  21  has a flow channel  210  with an inlet  210   a  and an outlet  210   b  (see  FIG. 4 ). The inlet  210   a  is located at a first end  211  of the first flow-channel plate  21 , and the outlet  210   b  is located at a second end  212  of the first flow-channel plate  21 . The first sides of the first battery bracket  20   a  and the second battery bracket  20   b  are fixed on the first connecting member  221 . The second sides of the first battery bracket  20   a  and the second battery bracket  20   b  are fixed on the second connecting member  222 . The first end  211  of the first flow-channel plate  21  is connected with the first connecting member  221 , and the second end  212  of the first flow-channel plate  21  is connected with the second connecting member  222 . After the cooling liquid (not shown) is introduced into the input channel  271 , the cooling liquid is transferred to the inlet  210   a  of the flow channel  210  of the first flow-channel plate  21  through the first junction channel  221   a  of the first connecting member  221 , so that the heat from the plural battery cells  26  is dissipated by the cooling liquid. Then, the cooling liquid is transferred to the second junction channel  222   a  of the second connecting member  222  through the outlet  210   b  of the flow channel  210 . Afterwards, the cooling liquid is discharged from the output channel  272 . Since the cooling liquid is transferred through the first connecting member  221 , the first flow-channel plate  21  and the second connecting member  222  and then discharged from the output channel  272 , the heat from the battery module  2  is dissipated by the cooling liquid. 
       FIG. 3  is a schematic view illustrating the combination of the first battery bracket and the second battery bracket of the battery module according to the first embodiment of the present invention. For clarification and brevity, the first flow-channel plate  21  is not shown in  FIG. 3 . Please refer to  FIGS. 2 and 3 . Each of the first battery bracket  20   a  and the second battery bracket  20   b  is a honeycomb structure with a plurality of hexagonal units. Preferably, the plural hexagonal units of the honeycomb structure are integrally formed with each other, but are not limited thereto. In some embodiments, the first battery bracket  20   a  and the second battery bracket  20   b  are made of nonconductive plastic materials, but are not limited thereto. 
     Please refer to  FIG. 3  again. Each of the first battery bracket  20   a  and the second battery bracket  20   b  comprises plural hollow portions  200  corresponding to respective hexagonal units of the honeycomb structure. In this embodiment, the hollow portion  200  is cylindrical space for accommodating a corresponding cylindrical battery cell  26 . It is noted that the profile of the hollow portion  200  is not restricted. Moreover, the hollow portion  200  has a first opening  201 , a second opening  202 , a third opening  203 , and a fourth opening  204 . The first opening  201  and the third opening  203  are opposed to each other. The second opening  202  and the fourth opening  204  are opposed to each other. In addition, the second opening  202  is disposed adjacent to the first opening  201  and the third opening  203 . 
     In this embodiment, the first opening  201  and the third opening  203  are located at a front side and a rear side of the hollow portion  200 , respectively. The second opening  202  and the fourth opening  204  are located at a top side and a bottom side of the hollow portion  200 , respectively. Moreover, a corresponding battery cell  26  is introduced into the hollow portion  200  through the first opening  201 . 
     Furthermore, the first battery bracket  20   a  comprises a plurality of first engaging structures  205 , and the second battery bracket  20   b  comprises a plurality of second engaging structures  206 . The plural first engaging structures  205  and the plural second engaging structures  206  are staggered. After the first engaging structures  205  of the first battery bracket  20   a  are engaged with corresponding second engaging structures  206  of the second battery bracket  20   b , the first battery bracket  20   a  and the second engaging structures  206  are combined together. Due to the engagement between the first engaging structures  205  and respective second engaging structures  206 , the first battery bracket  20   a  and the second battery bracket  20   b  are securely fixed and stacked on each other. 
     From the above discussions, since the first battery bracket  20   a  and the second battery bracket  20   b  are modularized structures, the first battery bracket  20   a  and the second battery bracket  20   b  can be easily fabricated and assembled and advantageous for mass production. Moreover, according to the practical requirements, the number of the plural battery brackets  20 , which are stacked on each other, may be varied. Therefore, the number of the plural battery cells  26  may be varied or the plural battery cells  26  may be selectively connected in parallel or in series. Consequently, the applications of the battery module can be enhanced. 
     Please refer to  FIG. 2  again. The liquid cold heat-dissipating mechanism  24  of the battery module  2  further comprises a plurality of thermal pads  23  corresponding to the second openings  202  and the fourth openings  204  of the plural hollow portions  200  of the first battery bracket  20   a  and the second battery bracket  20   b . In a preferred embodiment, the plural thermal pads  23  are inserted into the second openings  202  and the fourth openings  204  of the plural hollow portions  200  and attached on the top sides and bottom sides of the battery cells  26 . Consequently, the plural thermal pads  23  provide the functions of buffering and positioning the battery cells  26 . 
     Moreover, in this embodiment, the plural thermal pads  23  are made of flexible and thermally-conductive materials, but are not limited thereto. Consequently, the uses of the plural thermal pads  23  may achieve the isolation efficacy and facilitate buffering and fixing the battery cells  26 . Under this circumstance, even if the battery cells  26  are suffered from vibration, the possibility of sliding the battery cells  26  will be minimized. Moreover, through the thermal pads  23 , the heat generated by the battery cells  26  can be effectively transferred to the first flow-channel plate  21 . 
     A process of assembling the battery module  2  will be illustrated as follows. Firstly, the plural battery cells  26  are accommodated within corresponding hollow portions  200  of the first battery bracket  20   a  and the second battery bracket  20   b . Then, the plural thermal pads  23  are inserted into the second openings  202  and the fourth openings  204  of the plural hollow portions  200  and attached on the top sides and bottom sides of the battery cells  26 . Then, first flow-channel plate  21  is arranged between the first battery bracket  20   a  and the second battery bracket  20   b . Meanwhile, the first sides of the plural thermal pads  23  are attached on the battery cells  26 , and the second sides of the plural thermal pads  23  are attached on the first flow-channel plate  21 . That is, the heat generated by the battery cells  26  can be effectively transferred to the first flow-channel plate  21 , and thus the heat-dissipating efficacy is enhanced. 
     In this embodiment, the first flow-channel plate  21  is made of a hard material such as copper, aluminum, stainless steel or any other metallic material. Alternatively, the first flow-channel plate  21  is made of a flexible material, but is not limited thereto. As shown in  FIG. 4 , the first flow-channel plate  21  is a wavy plate with a cambered surface matching the cambered surfaces of the first battery bracket  20   a , the second battery bracket  20   b  and the battery cells  26 . 
     The first flow-channel plate  21  has the flow channel  210  with the inlet  210   a  and the outlet  210   b . The inlet  210   a  is located at the first end  211  of the first flow-channel plate  21 , and the outlet  210   b  is located at the second end  212  of the first flow-channel plate  21 . The cooling liquid is introduced into the flow channel  210  of the first flow-channel plate  21  through the inlet  210   a  of the flow channel  210 , and then discharged from the outlet  210   b  of the flow channel  210 . Consequently, the heat from the battery cells  26  (see  FIG. 2 ) could be dissipated by the cooling liquid. 
     Please refer to  FIG. 2  again. The first end  211  and the second end  212  of the first flow-channel plate  21  are respectively connected with the first connecting member  221  and the second connecting member  222  by a soft soldering process, a chemical welding process, a cured-in-place gasket (CIPG) process, an oil-sealing process or any other coupling means. 
     In some embodiments, the first connecting member  221  and the second connecting member  222  are rigid bodies made of hard materials in order for connecting and supporting the first battery bracket  20   a  and the second battery bracket  20   b . Alternatively, in some embodiments, the first connecting member  221  and the second connecting member  222  are soft tubes made of flexible materials. 
     Please refer to  FIGS. 2 and 4  again. The first connecting member  221  and the second connecting member  222  have the first junction channel  221   a  and the second junction channel  222   a , respectively. The first junction channel  221   a  runs through the first connecting member  221 , and the second junction channel  222   a  runs through the second connecting member  222 . The first junction channel  221   a  has an inlet  221   b  and an outlet  221   c , and the second junction channel  222   a  has an inlet  222   b  and an outlet  222   c . The inlet  221   b  is located at a top surface of the first connecting member  221 , and the inlet  222   b  is located at a top surface of the second connecting member  222 . The outlet  221   c  is located at a bottom surface of the first connecting member  221 , and the outlet  222   c  is located at a bottom surface of the second connecting member  222 . In addition, the inlet  221   b  of the first junction channel  221   a  of the first connecting member  221  is in fluid communication with the inlet  210   a  of the flow channel  210  of the first flow-channel plate  21  and the input channel  271 . The outlet  221   c  of the first junction channel  221   a  of the first connecting member  221  is a closed structure. The inlet  222   b  of the first junction channel  222   a  of the second connecting member  222  is in fluid communication with the outlet  210   b  of the flow channel  210  of the first flow-channel plate  21 . In addition, the outlet  222   c  of the second junction channel  222   a  of the second connecting member  222  is further in fluid communication with the output channel  272 . After the first battery bracket  20   a , the second battery bracket  20   b , the plural thermal pads  23  and the first flow-channel plate  21  are combined together, the first connecting member  221  and the second connecting member  222  are located at two opposite sides of the first battery bracket  20   a  and the second battery bracket  20   b , and the first connecting member  221  and the second connecting member  222  are connected with the first flow-channel plate  21 . For assembling more layers of battery brackets  20 , the battery module  2  comprises a plurality of first connecting members  221  in the stack arrangement and a plurality of second connecting members  222  in the stack arrangement. After the plural first connecting members  221  are stacked on each other, the outlet  221   c  of the first junction channel  221   a  in the upper first connecting member  221  is connected with the inlet  221   b  of the first junction channel  221   a  in the adjacent lower first connecting member  221 . Consequently, the first junction channels  221   a  between any two adjacent first connecting members  221  are in fluid communication with each other. Similarly, the second junction channels  222   a  among the plural second connecting members  222  are in fluid communication with each other. 
     In this embodiment, the battery module  2  further comprises a plurality of seal rings  28 . The seal rings  28  are sheathed around the inlet  221   b  and the outlet  221   c  of the first junction channel  221   a  of the first connecting member  221  and the inlet  222   b  and the outlet  222   c  of the second junction channel  222   a  of the second connecting member  222 . The uses of the seal rings  28  may prevent leakage of the cooling liquid from the first junction channel  221   a  and the second junction channel  222   a.    
     The battery module  2  further comprises a fixing mechanism  25 . The fixing mechanism  25  comprises at least two upper pressing plates  251  and at least two lower pressing plates  252 , which are disposed and fixed on the first connecting member  221  and the second connecting member  222 , respectively. As shown in  FIG. 2 , the input channel  271  is disposed on the upper pressing plate  251  which is fixed on the first connecting member  221 . In addition, the output channel  272  is disposed on the lower pressing plate  252  which is fixed on the second connecting member  222 . 
     In this embodiment, the upper pressing plates  251  and the lower pressing plates  252  of the fixing mechanism  25  are made of hard materials such as copper, aluminum, stainless steel or any other metallic material. Alternatively, in some other embodiments, the fixing mechanism  25  is made of a flexible material in order to comply with the first flow-channel plate  21 , the first connecting member  221  and the second connecting member  222 . Furthermore, the fixing mechanism  25  may be fixed on the first connecting member  221  and the second connecting member  222  by a screwing means or any other fixing means. 
     From the above discussions, the battery module  2  is assembled by the following steps. Firstly, the plural battery cells  26  are accommodated within corresponding hollow portions  200  of the first battery bracket  20   a  and the second battery bracket  20   b . Then, the plural thermal pads  23  are inserted into the second openings  202  and the fourth openings  204  of the plural hollow portions  200  and attached on the top sides and the bottom sides of the battery cells  26 . Then, first flow-channel plate  21  is arranged between the first battery bracket  20   a  and the second battery bracket  20   b . Then, the first connecting member  221  and the second connecting member  222  are disposed on two opposite sides of the first flow-channel plate  21 . Afterwards, the top sides and the bottom sides of the first connecting member  221  and the second connecting member  222  are fixed by the fixing mechanism  25 . Under this circumstance, a multilayered battery module  2  of the present invention is fabricated. 
     After the battery module  2  is fabricated, the heat generated by the battery cells  26  is transferred to the first flow-channel plate  21  through the plural thermal pads  23 . Since the cooling liquid is introduced into the input channel  271 , the cooling liquid is transferred to the inlet  210   a  of the flow channel  210  of the first flow-channel plate  21  through the first junction channel  221   a  of the first connecting member  221 , the heat from the plural battery cells  26  can be dissipated by the cooling liquid. Then, the cooling liquid is transferred to the second junction channel  222   a  of the second connecting member  222  through the outlet  210   b  of the flow channel  210 . Afterwards, the cooling liquid is discharged from the output channel  272 . Since the cooling liquid is transferred through the first connecting member  221 , the first flow-channel plate  21  and the second connecting member  222  and then discharged from the output channel  272 , the heat from the battery module  2  is dissipated by the cooling liquid. 
     In some other embodiments, the first flow-channel plate  21 , the first connecting member  221 , the second connecting member  222 , the input channel  271 , the output channel  272  or the fixing mechanism  25  of the battery module  2  may be omitted. Under this circumstance, a vacant space (not shown) within the battery module  2  is created. The vacant space is served as an airflow channel for allowing the airflow to go through. In a case that an active heat-dissipating device such as a fan (not shown) is employed, the heat generated by the battery cells may be dissipated away through the vacant space. 
       FIG. 5  is a schematic exploded view illustrating a battery module according to a second embodiment of the present invention. As shown in  FIG. 5 , the battery module  3  comprises a plurality of battery brackets  30  and a liquid cold heat-dissipating mechanism  31 . In this embodiment, the plural battery brackets  30  comprise a first battery bracket  30   a , a second battery bracket  30   b  and a third battery bracket  30   c , which are stacked on each other. Moreover, each of the first battery bracket  30   a , the second battery bracket  30   b  and the third battery bracket  30   c  comprises a plurality of hollow portions  300  for accommodating a plurality of battery cells  36 . The materials and configurations of the plural battery brackets  30  are identical to the battery module of the first embodiment, and are not redundantly described herein. 
     In this embodiment, the liquid cold heat-dissipating mechanism  31  comprises an input channel  371 , an output channel  372 , a plurality of flow-channel plates  32 , a plurality of thermal pads  33 , a first connecting member  341 , a second connecting member  342 , and a fixing mechanism  35 . The liquid cold heat-dissipating mechanism  31  utilizes a cooling liquid to remove the heat from plural battery cells  36 , which are disposed on the plural battery brackets  30 . In this embodiment, the first battery bracket  30   a , the second battery bracket  30   b  and the third battery bracket  30   c  of the battery module  3  are stacked on each other. In addition, the plural flow-channel plates  32  comprise a first flow-channel plate  32   a  and a second flow-channel plate  32   b . The first flow-channel plate  32   a  is arranged between the first battery bracket  30   a  and the second battery bracket  30   b . The second flow-channel plate  32   b  is arranged between the second battery bracket  30   b  and the third battery bracket  30   c . The cooling liquid is transferred through the first flow-channel plate  32   a  and the second flow-channel plate  32   b . Consequently, the heat from the battery cells  36  can be dissipated by the cooling liquid. 
     In this embodiment, each of the first flow-channel plate  32   a  and the second flow-channel plate  32   b  has a flow channel (not shown), a first end  320  and a second end  321 . The structure of the flow channel is similar to that of the battery module of the first embodiment, and is not redundantly described herein. Similarly, the first flow-channel plate  32   a  and the second flow-channel plate  32   b  may be made of hard materials or flexible materials. 
     Similarly, plural thermal pads  33  are arranged between the first battery bracket  30   a  and the first flow-channel plate  32   a , and aligned with the fourth openings  304  of the plural hollow portions  300  of the first battery bracket  30   a . Similarly, additional plural thermal pads  33  are arranged between the first flow-channel plate  32   a  and the second battery bracket  30   b , and aligned with the second openings  302  of the plural hollow portions  300  of the second battery bracket  30   b . Similarly, additional plural thermal pads  33  are arranged between the second battery bracket  30   b  and the second flow-channel plate  32   b . Similarly, additional plural thermal pads  33  are arranged between the second flow-channel plate  32   b  and the third battery bracket  30   c . Consequently, the plural thermal pads  33  provide the functions of buffering and positioning the battery cells  36 . 
     In this embodiment, the battery module  3  further comprises a plurality of first connecting members  341  and a plurality of second connecting members  342 . The liquid cold heat-dissipating mechanism  31  is connected with the two opposite sides of the first flow-channel plate  32   a  and the second flow-channel plate  32   b  through the first connecting members  341  and the second connecting members  342 . That is, the plural first connecting members  341  are located at the first ends  320  of the first flow-channel plate  32   a  and the second flow-channel plate  32   b , and the plural second connecting members  342  are located at the second ends  321  of the first flow-channel plate  32   a  and the second flow-channel plate  32   b . In addition, plural first junction channels  341   a  and plural second junction channels  342   a  are disposed within the first connecting members  341  and the second connecting members  342 , respectively. Moreover, the plural first connecting members  341  are stacked on each other, so that the first junction channels  341   a  within respective first connecting members  341  are in fluid communication with each other. Similarly, the plural second connecting members  342  are stacked on each other, so that the second junction channels  342   a  within respective second connecting members  342  are in fluid communication with each other. Moreover, the first junction channels  341   a  within the topmost first connecting member  341  is in fluid communication with the input channel  371 . The second junction channels  342   a  within the bottommost second connecting members  342  is in fluid communication with the output channel  372 . 
     Moreover, the battery module  3  further comprises a plurality of seal rings  38 . The seal rings  38  are sheathed around the inlets and the outlets of the first junction channels  341   a  and the second junction channels  342   a . Furthermore, the fixing mechanism  35  comprises plural upper pressing plates  351  and plural lower pressing plates  352 , which are disposed and fixed on the first connecting member  341  and the second connecting member  342 , respectively. 
     From the above discussions, the first battery bracket  30   a , the second battery bracket  30   b  and the third battery bracket  30   c  are modularized structures and stacked on each other. The first flow-channel plate  32   a  is arranged between the first battery bracket  30   a  and the second battery bracket  30   b . The second flow-channel plate  32   b  is arranged between the second battery bracket  30   b  and the third battery bracket  30   c . The first ends  320  of the first flow-channel plate  32   a  and the second flow-channel plate  32   b  are in fluid communication with the plural first connecting members  341 , and the second ends  321  of the first flow-channel plate  32   a  and the second flow-channel plate  32   b  are in fluid communication with the plural second connecting members  342 . After the cooling liquid (not shown) is introduced into the liquid cold heat-dissipating mechanism  31  through the input channel  371 , the cooling liquid is transferred through the first junction channels  341   a  of the plural first connecting members  341 , and then transferred to the flow channel (not shown) of the first flow-channel plate  32   a  and the flow channel (not shown) of the second flow-channel plate  32   a  through the first ends  320  of the first flow-channel plate  32   a  and the second flow-channel plate  32   b . Consequently, the heat from the plural battery cells  36  is dissipated by the cooling liquid. Then, the cooling liquid is transferred to the second junction channels  342   a  of the plural second connecting member  342  through the second ends  321  of the first flow-channel plate  32   a  and the second flow-channel plate  32   b . Afterwards, the cooling liquid is discharged from the output channel  372 . Since the cooling liquid is transferred through the plural first connecting members  341 , the plural flow-channel plates  32  and the plural second connecting member  342 , the heat from the battery module  3  can be effectively dissipated by the cooling liquid. 
     In the above two embodiments, the battery module of the present invention comprises plural battery brackets and a liquid cold heat-dissipating mechanism. The plural battery brackets are modularized structures and stacked on each other. The liquid cold heat-dissipating mechanism is arranged between the plural battery brackets and located at bilateral sides of the plural battery brackets. The liquid cold heat-dissipating mechanism is used for removing the heat from the battery cells. It is noted that the number of the battery brackets may be varied according to the practical requirements. For example, the battery module may comprise two, three, four or five layers of battery brackets. Similarly, the number of the thermal pads and the number of the flow-channel plates may be varied according to the number of the battery brackets. 
     From the above description, the present invention provides a battery module. The battery module of the present invention comprises plural battery brackets and a liquid cold heat-dissipating mechanism. The plural battery brackets are modularized structures and stacked on each other. The plural battery brackets comprise plural hollow portions for accommodating plural battery cells. Moreover, plural thermal pads and a flow-channel plate are arranged between every two adjacent battery brackets. Moreover, a first connecting member and a second connecting member are located at two opposite sides of the battery brackets and the flow-channel plate. In addition, a first junction channel and a second junction channel are disposed within the first connecting member and the second connecting member, respectively. The first junction channel of the first connecting member is in fluid communication with an input channel for transferring a cooling liquid from the first connecting member to the flow channel of the flow-channel plate. Then, the cooling liquid is transferred to the second junction channel of the second connecting member, and discharged from an output channel. Consequently, the heat from the battery cells can be effectively dissipated by the cooling liquid. Since the battery brackets are modularized structures, the battery brackets can be easily fabricated and assembled and advantageous for mass production. Moreover, after the battery cells are accommodated within the hollow portions of the battery brackets, the battery cells can be securely fixed by the thermal pads. Consequently, the possibility of vibrating or rotating the battery cells will be minimized. 
     While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.