Patent Publication Number: US-2020280113-A1

Title: Liquid-proof metal-air electrode component and metal-air cell

Description:
TECHNICAL FIELD 
     The utility model belongs to the field of a metal-air cell, and in particular, relates to a liquid-proof metal-air electrode component and a metal-air cell. 
     BACKGROUND 
     A metal-air cell is a fuel cell of a new concept formed by replacing hydrogen energy with metal fuel, and is expected to become a new generation of green energy. The metal-air cell exploits many advantages of a fuel cell, provides zinc, aluminum and other metals to the reaction position in the cell like hydrogen, and forms a continuous power generation device together with oxygen, with the advantages of being non-toxic, non-polluting, stable in discharge voltage, high in specific energy, low in internal resistance, long in storage life, relatively low in price, low in process technology requirements, high in specific power, etc. The metal-air cell is rich in cheap resources and renewable, and simpler than a hydrogen fuel cell structure. The metal-air cell is a new energy with promising development and application. 
     However, because the metal-air cell uses a metal salt solution as the ionic conductor, the metal salt solution is highly corrosive to the metal parts in the electrode component; after prolonged use, it is very easy to result in the problem of metal salt solution leakage in the electrode component due to corrosion of the metal parts. 
     SUMMARY 
     In view of the above problem existing in the prior art, the utility model provides a liquid-proof metal-air electrode component and a metal-air cell. 
     In order to achieve the above object, the utility model provides the following technical solution: a liquid-proof metal-air electrode component, comprising: a plastic bottom shell, an air electrode and a metal electrode, wherein the metal electrode and the air electrode are respectively provided on the back surface and the front surface of the plastic bottom shell, the metal electrode is fixed to the plastic bottom shell, and the periphery of the air electrode is encapsulated in the plastic bottom shell. 
     Preferably, the periphery of the air electrode is encapsulated in the plastic bottom shell through an injection molding process; a plastic middle frame for encapsulating the air electrode is formed in the injection molding encapsulating process, the plastic middle frame and the plastic bottom shell are integrated, and the plastic middle frame and the plastic bottom shell cooperate with each other to achieve the injection molding edge sealing structure of the air electrode. 
     Preferably, the air electrode comprises an air electrode body and a conductive side extending from the air electrode body, the metal-air electrode component further comprises a conductive sheet, which is in electric contact with the conductive side; both the conductive side and the conductive sheet are encapsulated in the plastic bottom shell. 
     Preferably, the metal-air electrode component further comprises a first conductive bolt and a second conductive bolt, the first conductive bolt extends into the plastic bottom shell to be in electric contact with the conductive sheet; and the metal electrode is fixed to the plastic bottom shell through a second conductive bolt. 
     Preferably, a sealing contact is formed between the first conductive bolt and the hole wall of the mounting hole in the plastic bottom shell; the second conductive bolt is sealed and fixed with the plastic bottom shell through a plastic gasket. 
     Preferably, the liquid-proof metal-air electrode component further comprises a first conductive elastic pin and a second conductive elastic pin used as output electrodes, respectively, wherein the first conductive elastic pin and the second conductive elastic pin are electrically connected to the first conductive bolt and the second conductive bolt through conductive foam, respectively. 
     Preferably, the liquid-proof metal-air electrode component further comprises a plastic surface shell, wherein the plastic surface shell covers the front surface of the plastic bottom shell, the surface shell is provided with a hollow area at the position corresponding to the air electrode, and the first conductive elastic pin and the second conductive elastic pin extend out of the plastic surface shell. 
     A metal-air cell, comprising: a liquid container, and a metal-air electrode component mounted on the liquid container, wherein the metal-air electrode component is a liquid-proof metal-air electrode component as described above, after pouring the liquid into the liquid container, the metal electrode of the metal-air electrode component is immersed in the liquid of the liquid container. 
     The beneficial effects of the utility model are as follows. 
     In the liquid-proof metal-air electrode component, the advantage of using an injection molding process to encapsulate the air electrode is that: an injection molding edge sealing is formed on the periphery of the air electrode, which ensures the sealing performance between the air electrode and the plastic bottom shell, and compared with the fixing method using screws and other fixing parts, it has better sealing performance and product consistency, thereby reducing product defect rate and improving product performance. 
     In addition, the air electrode in the metal-air electrode component has a two-layer sealing structure: 
     a first layer of sealing structure: the periphery of the air electrode is encapsulated in the air electrode mounting position of the plastic bottom shell through an injection molding process; 
     a second layer of sealing structure: a sealing contact is formed between the first conductive bolt and the hole wall of the mounting hole in the plastic bottom shell. The cooperation of the two-layer sealing structure can ensure an excellent sealing effect between the air electrode and the plastic bottom shell, reduce the possibility of solution leakage, and enable the metal-air electrode component to have higher reliability. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to more clearly explain the technical solutions in the embodiments of the utility model, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the utility model. For those skilled in the art, other drawings can be obtained based on these drawings without paying creative labor, in which: 
         FIG. 1  is a schematic structural diagram of a metal-air cell according to an embodiment of the utility model; 
         FIGS. 2 and 3  are perspective diagrams of a metal-air electrode component in a metal-air cell shown in  FIG. 1 ; 
         FIG. 4  is an exploded diagram of a metal-air electrode component shown in  FIGS. 2 and 3 ; 
         FIG. 5  is a schematic structural diagram of an air electrode, a conductive sheet and a plastic middle frame in a metal-air electrode component shown in  FIGS. 2 and 3 . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The technical solutions in the embodiments of the utility model will be described clearly and completely below. Obviously, the described embodiments are only some embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without paying creative labor shall fall within the protection scope of the utility model. 
     In the claims, description and drawings of the utility model, unless expressly defined otherwise, the terms such as “first”, “second”, or “third” are used to distinguish different objects, rather than describe a specific order. 
     As shown in  FIG. 1 , this embodiment provides a metal-air cell comprising: a liquid container  10  and a metal-air electrode component  20  mounted on the liquid container  10 . The liquid container  10  is used to contain metal salt solution of an ion conductor. In this embodiment, the liquid container  10  is a bag-type container. Of course, it is not limited to this embodiment, and the liquid container  10  may also be other suitable containers, as long as it can meet the requirements of the liquid container of the metal-air cell. 
     As shown in  FIG. 2 ,  FIG. 3 ,  FIG. 4  and  FIG. 5 , the metal-air electrode component  20  comprises: a plastic bottom shell  21 , a plastic surface shell  22 , an air electrode  23 , a metal electrode  24 , a conductive sheet  25 , and a first conductive bolt  26 , a second conductive bolt  27 , a first conductive elastic pin  28  and a second conductive elastic pin  29 . 
     The plastic surface shell  22  covers and cooperates with the front surface of the plastic bottom shell  21  to form an outer shell of the metal-air electrode component. Moreover, the plastic surface shell  22  is provided with a hollowed region  2201  at the position corresponding to the air electrode  23 , and the hollowed region  2201  is used to penetrate air. 
     The metal electrode  24  and the air electrode  23  are respectively provided on the back surface and the front surface of the plastic bottom shell  21 . In this embodiment, the metal electrode  24  is detachably fixed to the plastic bottom shell  21 , and the periphery of the air electrode  23  is encapsulated in the plastic bottom shell  21 . 
     It should be noted that the air electrode  23  is encapsulated in the air electrode mounting position  2101  of the plastic bottom shell  21  through an injection molding process. Moreover, a plastic middle frame  2102  for encapsulating the air electrode  23  is formed in the injection molding encapsulating process. The plastic middle frame  2102  and the plastic bottom shell  21  are integrated, and the shapes of the plastic middle frame  2102  and the air electrode  23  are substantially the same, so that the plastic middle frame  2102  and the plastic bottom shell  21  cooperate with each other to achieve the injection molding edge sealing structure of the air electrode  23 . 
     The advantage of using an injection molding process to encapsulate the air electrode  23  is that: an injection molding edge sealing is formed on the periphery of the air electrode  23 , which ensures the sealing performance between the air electrode  23  and the plastic bottom shell  21 , and compared with the fixing method using screws and other fixing parts, it has better sealing performance and product consistency, thereby reducing product defect rate and improving product performance. 
     In addition, the air electrode  23  comprises an air electrode body  231  and a conductive side  232  extending from the air electrode body  231 . The metal-air electrode component further comprises a conductive sheet  25 , which is in electric contact with the conductive side  232 . In this embodiment, both the conductive side  232  and the conductive sheet  25  are encapsulated in the plastic bottom shell  21 . That is, both the conductive side  232  and the conductive sheet  25  are fixed by injection molding through the plastic middle frame  2102 . 
     In this embodiment, the first conductive bolt  26  extends into the plastic bottom shell  21  to be in electric contact with the conductive sheet  25 ; and the metal electrode  24  is fixed to the plastic bottom shell  21  through the second conductive bolt  27 . It should be noted that the metal electrode  24  is detachably fixed to the plastic bottom shell  21  through the second conductive bolt  27 , so that it is convenient for the user to replace the metal electrode  24 . 
     In order to further improve the sealing performance, a sealing contact is formed between the first conductive bolt  26  and the hole wall of the mounting hole  2103  in the plastic bottom shell  21 . Specifically, in the injection molding encapsulating process, the mounting hole  2103  is formed on the plastic middle frame  2102 ; after the air electrode  23  is encapsulated in the plastic bottom shell  21 , the first conductive bolt  26  is screwed into the mounting hole  2103 ; in order to ensure to have a good sealing performance after the first conductive bolt  26  is screwed into the mounting hole  2103 , the diameter of the mounting hole  2103  is slightly smaller than the diameter of the first conductive bolt  26 , so that a tight sealing contact is formed therebetween to achieve the purpose of sealing. It should be understood that the air electrode  23  provided in this embodiment uses a conductive bolt as a conductive member. Of course, it is not limited to this embodiment, and other suitable conductive members can also be used to conduct electricity, such as conductive elastic posts, conductive pillars, or conductive wires, which is not limited in the utility model. 
     In addition, the second conductive bolt  27  is sealed and fixed with the plastic bottom shell  21  through a plastic gasket. A plastic gasket is sleeved on the second conductive bolt  27 , and the plastic gasket is used for sealing and fixing. 
     Therefore, the air electrode  23  in the metal-air electrode component provided by the utility model has a two-layer sealing structure: 
     a first layer of sealing structure: the periphery of the air electrode  23  is encapsulated in the air electrode mounting position  2101  of the plastic bottom shell  21  through an injection molding process; 
     a second layer of sealing structure: a sealing contact is formed between the first conductive bolt  26  and the hole wall of the mounting hole  2103  in the plastic bottom shell  21 . 
     The cooperation of the two-layer sealing structure can ensure an excellent sealing effect between the air electrode  23  and the plastic bottom shell  21 , reduce the possibility of solution leakage, and enable the metal-air electrode component to have higher reliability. 
     In addition, the first conductive elastic pin  28  and the second conductive elastic pin  29  are used as output electrodes, and both the first conductive elastic pin  28  and the second conductive elastic pin  29  extend out of the plastic surface shell  22 . In this embodiment, the first conductive elastic pin  28  and the second conductive elastic pin  29  are electrically connected to the first conductive bolt  26  and the second conductive bolt  27  through conductive foam  30 , respectively. 
     The processing process of the metal-air electrode component is as follows: 
     Step 1: the air electrode  23  is mounted in the air electrode mounting position  2101  of the plastic bottom shell  21 , and the conductive sheet  25  is pressed against the conductive side  232  of the air electrode  23 ; 
     Step 2: the injection molding process is used to encapsulate the periphery of the air electrode  23  in the plastic bottom shell  21  to form an injection molding edge sealing structure of the air electrode  23 , and the conductive sheet  25  is also encapsulated in the plastic bottom shell  21 . 
     Step 3: the first conductive bolt  26  and the second conductive bolt  27  are mounted, respectively, the first conductive bolt  26  extends into the plastic bottom shell  21  to be in electric contact with the conductive sheet  25 , and the metal electrode  24  is fixed to the plastic bottom shell  21  through the second conductive bolt  27 ; 
     Step 4: the conductive foam  30  is affixed, so that the first conductive elastic pin  28  and the second conductive elastic pin  29  are electrically connected to the first conductive bolt  26  and the second conductive bolt  27  through the conductive foam  30 , respectively; 
     Step 5: the plastic surface shell covers and is fixed to the front surface of the plastic bottom shell  21 . 
     The above is only an embodiment of the utility model, rather than limit the patent scope of the utility model. Any equivalent structure or equivalent process transformation made using the contents of the specification of the utility model, which is directly or indirectly used in other related technical fields, is similarly included in the patent protection scope of the utility model.