Patent Publication Number: US-2015086827-A1

Title: Battery module having heat dissipating assembly

Description:
BACKGROUND  
     1. Technical Field 
     The present disclosure relates to battery modules, and particularly to a battery module having a heat dissipating assembly. 
     2. Description of Related Art 
     A battery module is formed by arranging multiple battery cells together. However, during a long operation time of the battery module, the battery module will generate a lot of heat. Nowadays, heat dissipating efficiency of the battery module is still less than satisfactory. 
     Therefore, it is desirable to provide a battery module that can overcome the above-mentioned limitations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
       Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. 
         FIG. 1  is an assembled, isometric view of a battery module, according to an exemplary embodiment. 
         FIG. 2  is an exploded, isometric view of the battery module of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION  
       FIGS. 1-2  show a battery module  100  for an electric car (not shown), according to an embodiment. In the illustrated embodiment, the battery module  100  includes a battery pack  10  and a heat dissipating assembly  20  for dissipating heat generated by the battery pack  10 . 
     The battery pack  10  includes a number of battery cells  11  connected in series to increase an output voltage. Each battery cell  11  is substantially cylindrical and includes an anode  111  and a cathode  112 . In the embodiment, the battery cell  11  is a lithium battery. 
     In the embodiment, the battery cells  11  are arranged in rows. The battery pack  10  also includes multiple rows of brackets  12  and a number of conductive pieces  13 . The multiple rows of brackets  12  are for holding the battery cells  11 . A number of the brackets  12  corresponds to a number of rows of the matrix. In the embodiment, there are thirty rows of battery cells  11 . Therefore, the battery pack  10  includes thirty brackets  12 . Each bracket  12  defines a number of holding holes  120 . Each holding hole  120  spatially corresponds to an anode  111 . Each bracket  12  is fastened to a row of battery cells  11 , such that each anode  111  is received in a holding hole  120 . The brackets  12  are made of insulating material, such as thermal plastic. 
     A thickness of the anode  111  is slightly larger than a thickness of the holding hole  120 . As such, the anode  111  is exposed out of the holding hole  120 . Each conductive piece  13  is located on the bracket  12 , such that the anode  111  electrically connects to the conductive piece  13 . The conductive piece  13  electrically connects the battery cells  11  of the same row in series to increase the output voltage. In the embodiment, the conductive piece  13  is made of copper alloy. 
     The heat dissipating assembly  20  includes a heat dissipating layer  21 , a heat dissipating sheet  22 , a heat exchange element  23 , and two heat pipes  24 . 
     The heat dissipating layer  21  is substantially rectangular and is positioned on the battery pack  10  for covering the anodes  111 , the conductive piece  13 , and the brackets  12 . The heat dissipating layer  21  includes a first surface  211  facing the battery pack  10 , and a second surface  212  facing away from the battery pack  10 . In the embodiment, the heat dissipating layer  21  is made of thermal-conducting material, such as silicone rubber. 
     In the embodiment, the heat dissipating sheet  22  is made of metal, such as copper, aluminum, or aluminum alloy. A shape and a size of the heat dissipating sheet  22  correspond to a shape and a size of the heat dissipating layer  21 , respectively. The heat dissipating sheet  22  is positioned on the second surface  212  of the heat dissipating layer  21 . The heat dissipating sheet  22  includes a bottom surface  221  contacting the second surface  212 , and a supporting surface  222  facing away from the bottom surface  221 . 
     The heat exchange element  23  is fixed on a sidewall of the battery pack  10 . The heat exchange element  23  stores coolant. Coolant is chosen according to a temperature at which the heat pipe  24  must operate. In the embodiment, the coolant is an alcohol. The heat exchange element  23  defines two input holes  230 . 
     The heat pipes  24  are tubes and are made of high thermal-conductivity material, such as copper or aluminium, and are attached to the supporting surface  222  of the heat dissipating sheet  22 . A number of capillaries are formed on an inner surface of the heat pipe  24 . One end of each heat pipe  24  is inserted into the heat exchange element  23  through the two input holes  230 . As such, the heat pipes  24  absorb the coolant through capillary action. In the embodiment, the heat pipes  24  are curved to increase a contact area between the heat pipes  24  and the supporting surface  222 . 
     In use, heat generated by the anodes  111  of the battery cells  11  is transferred to the heat dissipating layer  21  through the brackets  12  and the conductive pieces  13 , and the heat dissipating sheet  22  collects the heat. The coolant absorbed by the heat pipes  24  is evaporated by absorbing heat from the supporting surface  222 . The coolant is then reabsorbed by the heat pipes  24  from the heat exchange element  23  through capillary action, and the cycle repeats. As such, the coolant absorbed by the heat pipes  24  absorbs and removes the heat collected by the heat dissipating sheet  22 . 
     In other embodiments, the heat dissipating sheet  22  can be made of insulating material and be directly positioned on the battery pack  10 , such that the heat dissipating layer  21  can be omitted. 
     In other embodiments, a number of the heat pipes  24  can be changed according to need. 
     It will be understood that the above particular embodiments are shown and described by way of illustration only. The principles and the features of the present disclosure may be employed in various and numerous embodiment thereof without departing from the scope of the disclosure as claimed. The above-described embodiments illustrate the possible scope of the disclosure but do not restrict the scope of the disclosure.