JP3829398B2 - Battery manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a battery manufacturing method in which a power generating element is formed by alternately laminating or winding positive and negative electrodes each having a separator fixed thereto.
[0002]
[Prior art]
A battery (an active material holding type chemical battery including a primary battery and a secondary battery) generally forms a power generation element by laminating or winding a positive and negative electrode on a separator. The separator is an insulator for separating these positive and negative electrodes, and a separator that can be impregnated with an electrolytic solution is used. For example, a wound-type cylindrical battery forms a power generation element by winding each band-shaped positive and negative electrodes through two band-shaped separators, and this power generation element is formed into a cylindrical battery container. Store in. In addition, a stacked prismatic battery forms a power generation element by stacking a plurality of thin plate-like positive and negative electrodes via a plurality of sheet-like separators, and the power generation element is formed into a square battery container. Store in.
[0003]
[Problems to be solved by the invention]
However, in the conventional battery manufacturing method, the electrode and separator are wound or laminated in a state where they are simply overlapped, so that the distance between the electrodes changes because the electrode and the separator are not in close contact with each other and are lifted up. In order to prevent the electrodes and separators from being overlapped, the power generation element is wound or stacked and once secured with tape, etc., and then stored in a sturdy battery container made of metal cans and pressed. In addition to troublesome work such as tape fastening, there is a problem that a thick and heavy battery container must be used.
[0004]
The present invention has been made in view of such circumstances, and by further adhering positive and negative electrodes having a separator fixed to one or both of them, this power generation element can be easily manufactured and a flexible sheet-like element can be produced. An object of the present invention is to provide a battery that can be stored in a battery container or the like.
[0005]
[Means for Solving the Problems]
That is, in order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that at least one of the positive and negative electrodes in which the separator is bonded to at least one of the electrodes is alternately arranged at least one by one. In a method for manufacturing a battery in which a power generation element is formed by winding through a separator bonded to an electrode of the electrode, one or more positive and negative electrodes are alternately alternately disposed via a separator bonded to at least one of the electrodes. The electrode placement step of placing the electrodes at intervals and the positive and negative electrodes arranged at intervals of at least one opposing surface of the electrode to which the separator is bonded and the electrode to which the separator is not bonded, or the separator to be bonded together An adhesive application step of applying an adhesive to at least one opposing surface of the positive electrode and the negative electrode, and a separator of positive and negative electrodes arranged with a gap therebetween An electrode bonding step of forming a power generation element by closely adhering the opposite surface of the electrode to which the separator is bonded and the opposite surface of the electrode to which the separator is not bonded, or the opposite surface of the positive electrode to the negative electrode to which the separator is bonded. It is characterized by.
[0006]
According to the means of the invention described in claim 1, since the positive and negative electrodes are bonded together through a separator bonded to one or both electrodes, the winding type power generation element is integrated. Can do. Therefore, even if the power generation element is wound with a tape or the like, or housed in a battery can or the like without being pressed, the distance between the electrodes changes or the overlap of the electrodes and separators shifts and the battery characteristics are impaired. Thus, not only the power generation element can be easily manufactured, but also the material and shape of the battery container are not limited. In addition, since the adhesive can be efficiently applied to the positive and negative electrodes and adhered, the productivity can be increased.
[0007]
In addition, the electrode to which the separator is bonded is formed by, for example, applying an adhesive sequentially to the long electrode and the separator, pressing them with a roll press to continuously bond them, and punching and molding them in predetermined shapes. , Can be manufactured efficiently in a lump.
[0008]
Further, in the invention according to claim 2, the positive and negative electrodes having the separator bonded to at least one of the electrodes are alternately stacked one by one or more via the separator bonded to at least one of the electrodes. In a method of manufacturing a battery in which a power generation element is formed by winding, positive and negative electrodes are alternately opposed one by one, with the distance between the positive and negative electrodes facing each other via a separator bonded to at least one of the electrodes. An electrode placement step in which one end side of the surface is wider than the other end side, and at least one of a positive electrode and a negative electrode arranged with a gap between them and an electrode to which the separator is not bonded Adhesive application step of applying an adhesive to the opposing surface, or at least one opposing surface of the positive electrode and the negative electrode to which the separator is bonded together, and with an interval between them The power generating element is formed by closely adhering the opposing surfaces of the placed positive and negative electrodes to which the separator is bonded and the electrodes to which the separator is not bonded, or the positive and negative electrodes to which the separator is bonded. And an electrode bonding step.
[0009]
According to the means of the second aspect of the invention, in addition to the effect of the first aspect, the interval between the positive and negative electrodes is widened on one end side, so that it can be easily applied by spraying an adhesive from the one end side. Will be able to. In addition, this invention is applied not only to a winding type but to a laminated type power generation element.
[0010]
Furthermore, the adhesive application step may be an adhesive sheet inserting step in which a double-sided adhesive sheet is inserted between the opposing surfaces of the positive and negative electrodes arranged at intervals or the opposing surfaces of the separator bonded to the electrodes.
[0011]
According to this means, instead of applying an adhesive, a positive and negative electrode is bonded by inserting a double-sided adhesive sheet made of a sheet-like adhesive or a double-sided adhesive sheet having an adhesive layer formed on both sides of the sheet. Can do.
[0012]
Furthermore, you may provide the electric power generation element accommodation process which accommodates the electric power generation element formed by the said electrode adhesion process in a barrier-type sheet-like battery container.
[0013]
According to this means, since the power generation element is integrated, there is a possibility that even if the power generation element is housed in a flexible sheet-like battery container, the distance between the electrodes may change or the electrodes and separators may not overlap. Thus, the battery container can be made thin, lightweight and inexpensive.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0015]
1 to 4 show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view showing a manufacturing process of a power generation element of a nonaqueous electrolyte secondary battery, and FIG. 2 is a diagram of the nonaqueous electrolyte secondary battery. FIG. 2 is a longitudinal sectional view showing the structure of an integrated power generation element, and FIG. 4 is a perspective view of a nonaqueous electrolyte secondary battery in which the power generation element is sealed with an aluminum laminate sheet.
[0016]
In the present embodiment, as shown in FIG. 4, a method for manufacturing a nonaqueous electrolyte secondary battery in which a laminated power generation element 1 is covered with an aluminum laminate sheet 2 and sealed will be described. As shown in FIG. 2, the power generation element 1 includes a plurality of positive electrodes 11, negative electrodes 12, and separators 13. The positive electrode 11 has a rectangular thin plate shape in which a positive electrode active material such as a lithium cobalt composite oxide is applied to a positive electrode current collector plate. The negative electrode 12 has a rectangular thin plate shape in which a negative electrode active material such as graphite is applied to a negative electrode current collector plate. The separator 13 is a square sheet such as a microporous resin film. And the separator 13 of the same size as this negative electrode 12 is previously adhere | attached on both surfaces of each negative electrode 12, respectively. The negative electrode 12 with the separator 13 bonded in this way is coated with an adhesive such as PVDF sequentially on a long strip-shaped negative electrode and the separator, and bonded together and pressed with a roll press to be continuously bonded and dried. By punching and molding each predetermined shape as shown in 2, it can be efficiently manufactured collectively. In the non-aqueous electrolyte secondary battery of this embodiment, the positive electrode 11 must be opposed to the negative electrode 12, and therefore, a long strip is punched into a size slightly smaller than the negative electrode 12.
[0017]
The negative electrodes 12 to which the positive electrode 11 and the separator 13 are bonded are alternately arranged one by one (electrode arrangement step). Further, in the non-aqueous electrolyte secondary battery, since the positive electrode 11 must face the negative electrode 12, the negative electrode 12 with the separator 13 bonded is disposed on each of the left and right ends. Then, as shown in FIG. 1, the lower portions of these electrodes 11 and 12 are respectively supported by a support body 3, and these support bodies 3 are respectively swung so as to open a fan around the lower part. As a result, the distance between the facing surface 11a of the positive electrode 11 and the facing surface 13a of the separator 13 bonded to the negative electrode 12 becomes wider toward the top.
[0018]
Thus, when the electrodes 11 and 12 spread in a fan shape, the adhesive 11 such as PVDF is sprayed between the electrodes 11 and 12 from above to adhere to the opposing surfaces 11a of the positive electrode 11 and the negative electrode 12, respectively. The adhesive A is applied to each facing surface 13a of the separator 13 (adhesive application step). At this time, the adhesive A may be applied by a method other than spraying, or may be applied only to one of the opposing surface 11a or the opposing surface 13a between the electrodes 11 and 12. Instead of applying the adhesive A, a double-sided adhesive sheet can also be inserted between the opposing surface 11a of the positive electrode 11 and the opposing surface 13a of the separator 13 adhered to the negative electrode 12 (adhesion sheet insertion). Process). The double-sided adhesive sheet is obtained by forming an adhesive into a sheet shape, or by forming an adhesive layer on both sides of a sheet material such as a thin resin or paper. Further, these adhesives (adhesive A) and double-sided adhesive sheets must be stable with respect to the electrolytic solution and can be impregnated or distributed with the electrolytic solution.
[0019]
When the application of the adhesive A and the like is completed, the support 3 is moved so that the fan is closed, thereby bringing the opposing surface 11a of the positive electrode 11 and the opposing surface 13a of the separator 13 adhered to the negative electrode 12 into close contact. (Electrode bonding step). Then, when the electrodes 11 and 12 that are brought into close contact with each other are dried in an atmosphere of 80 ° C. while being pressed from both sides, the opposing surfaces 11a and 13a are bonded to each other, and a laminated power generation element as shown in FIG. 1 is formed.
[0020]
As shown in FIG. 4, the power generation element 1 is covered with an aluminum laminate sheet 2 having a barrier property, filled with a nonaqueous electrolyte and sealed to form a nonaqueous electrolyte secondary battery. (Power generation element storage process). At this time, the lead 4 connected to each positive electrode 11 and each negative electrode 12 of the power generation element 1 is surely sealed in a state in which the tip portion protrudes from between the laminated aluminum laminate sheets 2. The nonaqueous electrolyte secondary battery formed in this way can be used, for example, as a card-type secondary battery by being housed in a card-type outer case. Note that the thicknesses of the positive electrode 11, the negative electrode 12, and the separator 13 shown in FIGS. 1 to 3 are drawn thicker than the actual thickness in order to make the configuration of the power generation element 1 easier to understand.
[0021]
In the non-aqueous electrolyte secondary battery having the above-described configuration, the positive electrode 11 is further bonded to the negative electrode 12 to which the separator 13 is bonded, so that the stacked power generation element 1 is integrated. There is no need to store it in a battery can and press it. Therefore, not only is the power generation element 1 easy to manufacture, but even if the power generation element 1 is stored in a flexible battery container such as the aluminum laminate sheet 2, the distance between the positive electrode 11 and the negative electrode 12 changes. Or the overlap of the positive electrode 11, the negative electrode 12, and the separator 13 is eliminated. In addition, since the adhesive A can be applied to the plurality of positive electrodes 11 and negative electrodes 12 in a lump and bonded together, the productivity of the power generating element 1 can be increased.
[0022]
In addition, although the said embodiment demonstrated the case where the positive electrode 11 was adhere | attached on the whole surface of the negative electrode 12 which adhere | attached the separator 13, these can also be adhere | attached partially. Moreover, in this case, the adhesive (adhesive A) or the double-sided adhesive sheet may not be impregnated with the electrolytic solution.
[0023]
In the above embodiment, the case where the separator 13 is fixed to the negative electrode 12 in advance has been described. However, if the insulation can be reliably performed, the separator 13 is adhered to the positive electrode 11 or the positive and negative electrodes 11, 12. It can also be adhered to one side of each.
[0024]
Furthermore, in the above embodiment, the case where the electrodes 11 and 12 are fanned out and the adhesive A is applied has been described. However, if the distance between the facing surfaces 11a and 13a is sufficiently wide, the electrodes 11 and 12 It is also possible to apply the adhesive A or the like while 12 is parallel.
[0025]
Furthermore, although the said embodiment demonstrated the nonaqueous electrolyte secondary battery, this invention can be similarly implemented not only to this but a primary battery and another secondary battery. However, in the case of a secondary battery that generates gas during charging, it is necessary to take measures to cope with the generation of this gas. Furthermore, the configurations of the positive electrode 11, the negative electrode 12, and the separator 13 can be arbitrarily changed according to the types of these batteries.
[0026]
Furthermore, in the said embodiment, although the laminated type electric power generation element 1 was demonstrated, it can implement similarly to electric power generation elements of other structures, such as a winding type. In the case of the winding type, the adhesive A can be applied just before winding the belt-like positive and negative electrodes 11 and 12, and the tension can be applied and the adhesive can be pressed and bonded.
[0027]
【The invention's effect】
As is apparent from the above description, according to the battery manufacturing method of the present invention, the power generating element can be integrated by bonding the positive and negative electrodes by adhesion via the separator. It becomes easy. In addition, this power generation element can be stored in a flexible sheet-like battery container or the like because there is no possibility that the distance between electrodes changes or the overlap of electrodes and separators shifts. Can contribute to cost reduction by reducing weight and weight.
[Brief description of the drawings]
FIG. 1, showing an embodiment of the present invention, is a longitudinal sectional view showing a manufacturing process of a power generating element of a nonaqueous electrolyte secondary battery.
FIG. 2, showing an embodiment of the present invention, is a longitudinal sectional view showing a configuration of a power generation element of a nonaqueous electrolyte secondary battery.
FIG. 3 is a longitudinal sectional view showing the structure of an integrated power generation element according to an embodiment of the present invention.
FIG. 4 is a perspective view of a non-aqueous electrolyte secondary battery in which an electric power generation element is sealed with an aluminum laminate sheet, showing an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electric power generation element 2 Aluminum laminate sheet 11 Positive electrode 12 Negative electrode 13 Separator A Adhesive

Claims (2)

  Manufacture of a battery in which a power generating element is formed by winding positive and negative electrodes, each having a separator bonded to at least one electrode, one by one or more alternately via a separator bonded to at least one electrode In the method, positive and negative electrodes are alternately arranged one by one or more, and an electrode placement step of placing the separators attached to at least one of the electrodes with a gap therebetween, and positive and negative electrodes arranged with a gap between them. An adhesive applying step of applying an adhesive to at least one opposing surface of the electrode to which the separator is bonded and the electrode to which the separator is not bonded, or to at least one opposing surface of the positive electrode and the negative electrode to which the separator is bonded , The opposite surfaces of the positive and negative electrodes arranged with a gap between them, the electrode to which the separator is bonded and the electrode to which the separator is not bonded, or Method for producing a battery, characterized in that the separator facing surfaces of the bonded positive and negative electrodes, and an electrode bonding step of forming the adhesive power generation element is brought into close contact.   A battery in which a power generating element is formed by laminating or winding one or more positive and negative electrodes each having a separator bonded to at least one of the electrodes, alternately via the separator bonded to at least one of the electrodes. In this manufacturing method, the distance between the positive and negative electrodes is made wider at one end side of the opposing surface than at the other end side through a separator bonded to at least one of the positive and negative electrodes alternately one by one. Electrode placement step, and the positive and negative electrodes arranged at intervals, at least one facing surface of the electrode to which the separator is bonded and the electrode to which the separator is not bonded, or the positive electrode to which the separator is bonded together And an adhesive application step of applying an adhesive to at least one of the opposing surfaces of the negative electrode, and a positive and negative electrode separator arranged with a gap therebetween An electrode bonding step of forming a power generation element by adhering the bonded electrode and the facing surface of the electrode to which the separator is not bonded, or the facing surfaces of the positive electrode and the negative electrode to which the separator is bonded together in close contact with each other. A battery manufacturing method.

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