Patent Publication Number: US-2016233462-A1

Title: Method for fixing electrodes of flexible battery

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a method for fixing electrodes of flexible battery. 
     2. Description of the Prior Art 
     A conventional flexible battery includes a shell made of aluminum foil, an anode plate, a cathode plate, and electrolysis fluid. To prevent the anode and cathode plates from floating in the shell, the plates are usually fixed on the inner wall of the shell by means of adhesive spread on the plates. 
     However, spreading the adhesive results in higher cost and much complicated process. On the other hand, the adhesive contacts the electrolysis fluid so as to be easy to decompose. In addition, the thickness of the battery cannot be reduced due to the adhesive. 
     SUMMARY OF THE INVENTION 
     The main object of the present invention is to provide a method for fixing electrodes of flexible battery to prevent from using adhesive and to make the flexible battery thinner. 
     To achieve the above and other objects, a method for fixing electrodes of flexible battery includes the following steps. 
     (1) Prepare an anode plate and a cathode plate: Each of the anode plate and the cathode plate is a metal sheet and has a conducting portion and a connecting portion at two ends thereof The connecting portion has a first face and a second face. The first face is spread with an activating agent. The second face has a coarse surface. 
     (2) Cover with an aluminum foil: Align the anode plate and the cathode plate adjacently and make the second faces thereof face upward. Cover the connecting portions of the anode plate and the cathode plate with the aluminum foil. At least part of the conducting portion of each of the anode plate and the cathode plate is exposed outside the aluminum foil. A face of the aluminum foil facing downward contacts the second faces of the anode plate and the cathode plate. The face of the aluminum foil facing downward is spread with a plastic layer. 
     (3) Thermo compression: Press and heat the aluminum foil with a thermo compression device located above the aluminum foil so that the plastic layer is adhered to the second face of each of the anode plate and the cathode plate. 
     Thereby, no adhesive is needed, and the battery can be thinner. 
     The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment(s) in accordance with the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an illustration of an anode plate and a cathode plate of the present invention; 
         FIG. 2  is an illustration of an anode plate and a cathode plate of the present invention at another angle; 
         FIGS. 3 to 6  are illustrations of steps of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Please refer to  FIG. 1  to  FIG. 6 , the method for fixing electrodes of flexible battery of the present invention includes the following steps. 
     (1) Prepare an anode plate  10  and a cathode plate  20 : Each of the anode plate  10  and the cathode plate  20  is a metal sheet. In the present embodiment, the anode plate is made of aluminum, and the cathode plate is made of copper. Each of the anode plate  10  and the cathode plate  20  has a conducting portion  11 , 22  and a connecting portion  11 , 21  at two opposite ends. The connecting portion  11 , 21  has a first face  111 , 211  and a second face  112 , 212 . The first face  111 , 211  is spread with an activating agent, and the second face  112 , 212  has a coarse surface. The conducting portion  12 , 22  is elongated. About the coarse surface, at least one of the anode plate and the cathode plate is made of electric erosion metal foil to directly form the coarse surface. Alternatively, at least one of the anode plate and the cathode plate is abraded to from the coarse surface or spread with a coating having bumps to form the coarse surface. 
     (2) Cover with the aluminum foil  40 : Align the anode plate  10  and the cathode plate  20  adjacently and place them on a silicon sheet  30  to make the second faces  112 , 212  face upward. Cover the connecting portions  11 , 21  with an aluminum foil  40 . At least part of each of the conducting portions  12 , 22  is exposed outside the aluminum foil  40 . The face of the aluminum foil  40  facing downward contacts the second faces  112 , 212  of the anode plate  10  and the cathode plate  20  and is spread with a plastic layer  41 . In the present embodiment, the plastic layer  41  is made of polypropylene. 
     (3) Thermo compression: Pressing and heating the aluminum foil  40  with a thermo compression device  50  located above the aluminum foil  40  to make the plastic layer  41  adhere onto the second faces  112 , 212  of the anode plate  10  and the cathode plate  20 . In the present embodiment, the thermo compression step is processed under a pressure of 1-6 kilograms per centimeter square and a temperature of 100-200 degrees Celsius. 
     Thereafter, place a separation membrane or other similar object between the anode plate and the cathode plate to separate them, and then fold the aluminum foil to package followed by filling with electrolysis fluid. Thereby, the flexible battery is provided. 
     In conclusion, the anode plate and the cathode plate can be fixed onto the aluminum foil easily, and performance of adhesion is improved because the coarse surface is thermo compressed to the plastic layer. Besides, no adhesive is needed so that cost is reduced and that the battery may be thinner.