Patent Publication Number: US-2020280025-A1

Title: Aluminum case

Description:
TECHNICAL FIELD 
     The present disclosure relates to the technical field of batteries, for example, an aluminum case. 
     BACKGROUND 
     In a power battery, an aluminum case is generally used as a load-bearing component of an outer case structure, and a cover plate is used as a closing component of the outer case structure, where the aluminum case is a box-like structure with an opening, and the cover plate is closed at the opening of the aluminum case to form the outer case of the battery. The aluminum case may be directly stretch-molded by an aluminum plate. After the battery is formed, the aluminum case, the cover plate and a positive cell are all connected and are positively charged. In order to avoid short circuit inside the battery during use, a negative cell will be externally covered with an insulating film to avoid contact short circuit between the negative cell and an inner surface of the aluminum case. However, with the use of batteries, especially for batteries equipped on mobile carriers such as power batteries, such as power batteries, the negative cell may constantly rub against the inner surface of the aluminum case, and if the insulating film covering the negative cell is damaged, a short circuit may occur, resulting in scrap of the battery and even other accidents. In addition, metal dust formed on the inner surface of the aluminum case during a processing of the aluminum plate may also easily cause the short circuit inside the battery and cause a security accident. 
     SUMMARY 
     The present disclosure provides an aluminum case. At least one of an inner surface and an outer surface of the aluminum case after being molded has an insulating layer, reducing metal dust, improving the safety of the battery, and reducing the subsequent production cost of the battery. 
     Provided is an aluminum case, including an aluminum plate, where the aluminum plate includes a plate body, and at least one surface of the plate body is attached with an insulating layer. 
     In one embodiment, the inner surface of the aluminum case is provided with the insulating layer. 
     In one embodiment, the outer surface of the aluminum case is provided with the insulating layer. 
     In one embodiment, the inner surface and the outer surface of the aluminum case are both provided with the insulating layer. 
     In one embodiment, the insulating layer is a plastic film. 
     In one embodiment, the plastic film is made from Polyethylene terephthalate (PET) or polypropylene (PP). 
     In one embodiment, the aluminum case is stamp-molded from the aluminum plate. 
     In one embodiment, the insulating layer is attached to a surface of the plate body by spraying. 
     In one embodiment, the insulating layer is attached to the surface of the plate body by hot-pressing. 
     In one embodiment, the insulating layer is attached to the surface of the plate body by adhesive. 
     In one embodiment, on the aluminum plate, the insulating layer and the plate body are not completely fixed, so that when the aluminum plate is stamp-stretched, the insulating layer is movable relative to the plate body. 
     In one embodiment, after the aluminum case is stretch-molded, the insulating layer and the plate body are cured to avoid detachment of the insulating layer and the plate body. 
     In one embodiment, a thickness of the insulating layer is configured in a range of 0.02 mm to 0.1 mm. 
     In the aluminum case provided by the present disclosure, an aluminum plate with the insulating layer is used to manufacture the aluminum case. In the manufacturing process, and in a processing of the aluminum plate, the generation of metal dust may be reduced, and the metal dust on the insulating layer is convenient to clean, reducing the risk of short circuit inside the battery caused by the metal dust, and preventing the metal dust on the outer surface of the aluminum case from falling on other components, which may cause potential security hazard. In addition, because the inner surface of the aluminum case has an insulating layer, even when the insulating film covering the negative cell is cracked during use, the negative cell is still not in direct contact with the plate body of the aluminum case to conduct electricity, thereby avoiding short circuit and improving a safety factor of the battery. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic structural diagram of an aluminum plate provided by an embodiment; 
         FIG. 2  is a schematic structural diagram of an aluminum case provided by an embodiment; 
         FIG. 3  is a schematic structural diagram of an aluminum plate provided by another embodiment; 
         FIG. 4  is a schematic structural diagram of an aluminum case provided by another embodiment; 
         FIG. 5  is a schematic structural diagram of an aluminum plate provided by another embodiment; and 
         FIG. 6  is a schematic structural diagram of an aluminum case provided by another embodiment. 
     
    
    
     Where:
       1 —aluminum plate,  11 —plate body,  12 —insulating layer.   

     DETAILED DESCRIPTION 
     The technical solutions of the present disclosure are described hereinafter through specific embodiments in conjunction with the accompanying drawings. 
     In the description of the present embodiment, it is to be understood that the orientation or position relationships indicated by terms such as “above”, “below”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside” are based on the orientation or position relationships shown in the drawings, merely for facilitating description of the present embodiment, and these relationships do not indicate or imply that the referred device or element must have a specific orientation and is constructed and operated in a specific orientation, and thus it is not to be construed as limiting the present embodiment. 
     As shown in  FIG. 2 , the present embodiment provides an aluminum case with an insulating layer on a surface of the aluminum case. After the aluminum case is molded, an inner surface and an outer surface are both provided with an insulating layer  12 . The aluminum case is made of an aluminum plate  1  as shown in  FIG. 1 . The aluminum plate  1  includes a plate body  11 , and both surfaces of the plate body  11  are respectively attached with the insulating layer  12 , so that the inner surface and the outer surface of the molded aluminum case are both provided with the insulating layer  12 . In one embodiment, the aluminum case may be stamp-molded from the aluminum plate  1 , for example, molded by stamp-stretching, which is convenient for manufacturing. A thickness of the insulating layer  12  may be set in a range of 0.02 mm to 0.1 mm, taking insulation performance and an overall size into consideration. 
     According to the present embodiment, the aluminum plate  1  with the insulating layer  12  is used to manufacture the aluminum case. In the manufacturing process, and in a processing of the aluminum plate  1 , the generation of the metal dust may be reduced, and the metal dust on the insulating layer  12  is convenient to clean, reducing the risk of short circuit inside a battery caused by the metal dust, and preventing the metal dust on the outer surface of the aluminum case from falling on other components, which may cause potential security hazard. In addition, because the inner surface of the aluminum case has the insulating layer  12 , even when an insulating film covering a negative cell is cracked during use, the negative cell is still not in direct contact with the plate body  11  of the aluminum case to conduct electricity, thereby avoiding short circuit and improving the safety factor of the battery. When the inner surface of the aluminum case has the insulating layer, the insulating film is no longer needed to cover the negative cell, saving the subsequent production cost of the battery and simplifying the subsequent battery manufacturing process. In addition, the insulating layer provided on the inner surface may also prevent an electrolyte from corroding the inner surface of the aluminum case. By using an aluminum plate with an insulating layer  12 , after the aluminum case is made, the outer surface of the aluminum case has the insulating layer  12 , and the film is no longer needed to additionally cover the external of the battery after the aluminum case and cover plate are assembled into the battery, simplifying the subsequent assembly process of the battery and saving the cost of subsequent additional films covering on the battery. 
     As shown in  FIG. 4 , the present embodiment provides an aluminum case with an insulating layer on an inner surface of the aluminum case. After the aluminum case is molded, the inner surface is provided with the insulating layer  12 . The aluminum case is made of an aluminum plate  1  as shown in  FIG. 3 . The aluminum plate  1  includes a plate body  11 , and an insulating layer  12  is attached to a surface of the plate body  11  corresponding to the inner surface of the aluminum case, so that the inner surface of the aluminum case after being molded has the insulating layer  12 . In one embodiment, the aluminum case may be stamp-molded from the aluminum plate  1 , for example, molded by stamp-stretching, which is convenient for manufacturing. A thickness of the insulating layer  12  may be set in a range of 0.02 mm to 0.1 mm, taking insulation performance and the overall size into consideration. 
     According to the present embodiment, the aluminum plate  1  with the insulating layer  12  is used to manufacture the aluminum case. In the manufacturing process, and in a processing of the surface where the insulating layer  12  is located, no metal dust is generated, which not only reduces the metal dust, but also is convenient for cleaning the metal dust on the inner surface of the aluminum case, reducing the risk of the short circuit inside a battery caused by the metal dust. In addition, because the inner surface of the aluminum case has the insulating layer  12 , even when the insulating film covering a negative cell is cracked during use, the negative cell is still not in direct contact with the plate body  11  of the aluminum case to conduct electricity, thereby avoiding short circuit and improving the safety factor of the battery. When the inner surface of the aluminum case has the insulating layer, the insulating film is no longer needed to cover the negative cell, saving the subsequent production cost of the battery and simplifying the subsequent battery manufacturing process. In addition, the insulating layer arranged on the inner surface may also prevent the electrolyte from corroding the inner surface of the aluminum case. 
     As shown in  FIG. 6 , the present embodiment provides an aluminum case with an insulating layer on an outer surface of the aluminum case. After the aluminum case is molded, the outer surface is provided with the insulating layer  12 , without additional films. The aluminum case is made of an aluminum plate  1  as shown in  FIG. 5 . The aluminum plate  1  includes a plate body  11 , and the insulating layer  12  is attached to a surface of the plate body  11  corresponding to the outer surface of the aluminum case, so that the outer surface of the aluminum case after being molded has the insulating layer  12 . In one embodiment, the aluminum case may be stamp-molded from the aluminum plate  1 , for example, molded by stamp-stretching, which is convenient for manufacturing. A thickness of the insulating layer  12  may be set in a range of 0.02 mm to 0.1 mm, taking the insulation performance and the overall size into consideration. 
     According to the present embodiment, the aluminum plate  1  with the insulating layer  12  is used to manufacture the aluminum case. In the processing of the surface where the insulating layer  12  is located, no metal dust is generated, which is convenient for cleaning the metal dust on the surface of the insulating layer  12 , preventing the metal dust on the outer surface of the aluminum case from falling on other components, which may cause potential security hazard. By using the aluminum plate with the insulating layer  12 , after the aluminum case is made, the outer surface of the aluminum case has the insulating layer  12 , and the film is no longer needed to additionally cover the external of the battery after the aluminum case and cover plate are assembled into the battery, simplifying the subsequent assembly process of the battery and saving the cost of subsequent additional films covering on the battery. 
     In the present embodiment, the insulating layer  12  may be arranged as the plastic film, and may adopt a highly insulating plastic film to provide good insulation performance. In one embodiment, the plastic film may be made of materials such as polyethylene terephthalate (PET) or polypropylene (PP), and the plastic film may also be made of other materials with better insulation properties. 
     The insulating layer  12  may be attached to the surface of the plate body  11  by a plurality of manners, such as spraying, hot-pressing, or adhesive, as long as a relative good attachment may be ensured. However, on the aluminum plate  1 , the insulating layer  12  and the plate body  11  are not completely fixed. If the insulating layer  12  and the plate body  11  are completely fixed, when the aluminum plate  1  is stamp-stretched, due to different extensions of the insulating layer  12  and the plate body  11 , the insulating layer  12  may be cracked and out of action. Therefore, in the present embodiment, the insulating layer  12  and the plate body  11  are not completely fixed, but have a certain amount of relative movement, so that when stamp-molded, the insulating layer  12  and the plate body  11  may be relatively moved to keep the insulating layer  12  intact, so as to prevent the insulating layer  12  from being cracked. 
     After the aluminum case is stretch-molded, the insulating layer  12  and the plate body  11  need to be cured. A plurality of curing manners may be used, such as heating or cooling an adhesive layer, so that the insulating layer  12  and the plate body  11  may be completely cured after the adhesive layer is cured, so as to avoid detachment of the insulating layer  12  and the plate body  11  on the aluminum case. 
     INDUSTRIAL APPLICABILITY 
     In an aluminum case provided by the present disclosure, an aluminum plate with an insulating layer is used to manufacture the aluminum case. In a manufacturing process, and in a processing of the aluminum plate, the generation of metal dust may be reduced, and the metal dust on the insulating layer is convenient to clean, reducing the risk of short circuit inside the battery caused by the metal dust, and preventing the metal dust on an outer surface of the aluminum case from falling on other components, which may cause potential security hazard. In addition, because an inner surface of the aluminum case has the insulating layer, even when the insulating film covering a negative cell is cracked during use, the negative cell is still not in direct contact with the plate body of the aluminum case to conduct electricity, thereby avoiding the short circuit and improving a safety factor of the battery.