JP2011009096A - Lamination type laminated battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated battery of which positive electrode and negative electrode are reusable without recovering a material from the electrodes used in the laminated battery.SOLUTION: In a lamination type laminated battery, a positive electrode 14 having a positive current collecting tab 4 and a negative electrode having a negative current collecting tab are housed in a lamination outer package with a positive lead terminal 1 connected to the positive current collecting tab 4 of an electrode stack laminated via a separator and a part of a negative lead terminal connected to the negative current collecting tab being led out to the outside. A fixing bar is inserted into holes provided to at least one of a positive electrode group element including the positive current collecting tab 4 having the positive electrode 14, a current collecting tab protective plate 9 arranged in contact with the positive current collecting tab 4, and the positive lead terminal 1, and a negative electrode group element including the negative current collecting tab having the negative electrode, the current collecting tab protective plate 9 arranged in contact with the negative current collecting tab, and the negative lead terminal, and the fixing bar is further inserted into a washer 11 for fixing.

Description

  The present invention relates to a laminated laminate battery.

  In recent years, lithium-ion batteries have been used as power sources for portable devices such as mobile phones and digital cameras due to demands for higher capacity and smaller size. In addition, a lithium ion battery having a high energy density and no memory effect is also used as a power source for an electric assist bicycle or electric tool.

  With increasing demand for lithium ion batteries, it is particularly required to reuse the positive electrode active material for lithium ion batteries from the viewpoint of effective use of resources.

  And in patent document 1, the process of eluting lithium and a transition metal element with an acid from the to-be-processed material separated from the metal member and containing a positive electrode active material, and the obtained acidic solution and sodium hydroxide are mixed. A step of precipitating transition metal hydroxide and the like, and a step of separating the precipitate from the solution, supplying carbon dioxide gas etc. to the solution after separation, and precipitating lithium carbonate, and precipitated lithium carbonate A method of recovering valuable materials from a lithium battery and a method of recycling a lithium battery by including a step of separating the solution from a solution is described.

Japanese Patent Laid-Open No. 2005-026088

  Patent Document 1 describes that the positive electrode material of the used lithium ion battery is once recovered and used again for the production of the electrode. The positive electrode once used for the lithium ion battery is reused in combination with a new negative electrode as it is. It's not that.

  FIG. 3 is a plan view showing an electrode laminate of a conventional laminated laminate battery. A battery element stacking portion 8 is prepared by stacking a positive electrode having a positive current collecting tab 4 and a negative electrode having a negative current collecting tab 7 with a separator interposed therebetween. The positive electrode current collecting tab 4 and the positive electrode lead terminal 1 provided with the insulating resin 2 are welded by the welding part 3. The negative electrode current collecting tab 7 and the negative electrode lead terminal 5 provided with the insulating resin 2 are welded at the welded portion 6. The battery element laminate portion 8 is housed in a laminate case, and an electrolyte is injected and the laminate case is thermally welded at the position of the insulating resin 2 and sealed.

  When the laminated laminate battery is subjected to a cycle test, the lithium ion acceptance characteristics of the negative electrode are deteriorated as compared with the first cycle according to the number of cycle tests, but the positive electrode characteristics are not deteriorated so much. Therefore, disassemble the laminated case of the laminated battery that has been assembled and used, cut the welded part of the positive electrode after use, and weld the remaining positive electrode current collector tab and a new positive electrode lead terminal equipped with insulating resin. By combining with a new negative electrode and a new laminate case, it is possible to assemble and use a laminated laminate battery again.

  However, from the viewpoint of the structure of the conventional electrode laminate, after disassembling the laminated case of the laminated battery that has been assembled once and cutting the welded part of the positive electrode after use, the remaining positive electrode current collecting tab is replaced with a new positive electrode extraction terminal. When re-welding, the length of the positive electrode current collecting tab is insufficient. Therefore, in the conventional laminate structure, it has not been possible to assemble a laminated laminate battery by directly reusing the positive electrode once used in the laminated laminate battery.

  That is, the technical problem of the present invention is to provide a multilayer laminate battery having a structure in which a multilayer laminate battery once assembled and used can be disassembled and a positive electrode or a negative electrode can be reused as it is.

  The laminated laminate battery of the present invention includes a positive electrode lead terminal connected to the positive electrode current collector tab of an electrode laminate in which a positive electrode having a positive electrode current collector tab and a negative electrode having a negative electrode current collector tab are laminated via a separator; A laminated laminate battery in which a part of a negative electrode lead terminal connected to the negative electrode current collector tab is pulled out and stored in a laminate outer package, the positive electrode current collector tab including the positive electrode and the positive electrode current collector Current collecting tab protection plate disposed in contact with the current collecting tab protective plate disposed in contact with the tab, the positive electrode group element having the positive electrode lead terminal, the negative electrode current collecting tab including the negative electrode, and the negative electrode current collecting tab A fixing bar is inserted into a hole provided in at least one of a negative electrode group element having a plate and the negative electrode lead terminal, and the fixing bar is further inserted into a washer and fixed.

  The laminated laminate battery according to the present invention is characterized in that the fixing rod is a screw fixing rod or a caulking fixing rod.

  The laminated laminate battery of the present invention is characterized in that the positive electrode lead terminal and the screw fixing rod or the caulking fixing rod are welded.

  In the laminated laminate battery of the present invention, the material for the current collecting tab protective plate and the screw fixing rod or the caulking fixing rod is aluminum in the positive electrode group, and copper or stainless steel in the negative electrode group. It is characterized by.

  In the laminated laminate battery of the present invention, the material for the current collecting tab protective plate and the screw fixing rod and the screw or the caulking fixing rod is aluminum in the positive electrode group, and copper or stainless steel in the negative electrode group. It is characterized by being steel.

  In the laminated laminate battery of the present invention, the welding is laser welding, resistance welding, or ultrasonic welding.

  According to the present invention, it is possible to provide a laminated battery having a structure in which a laminated battery once assembled and used can be disassembled and the positive electrode or the negative electrode can be reused as it is.

The schematic cross section which shows the positive electrode group of this invention. The schematic cross section which shows the positive electrode group of the 2nd form of this invention. The top view which shows the electrode laminated body of the conventional lamination type laminated battery.

  An embodiment of the present invention will be described.

  According to the present invention, the positive electrode group can be taken out without causing damage after disassembling the laminated battery that has been assembled and used once, so the positive electrode group can be reused as it is by combining it with a new negative electrode group and a laminate case. Thus, a new laminated laminate battery can be produced and used. The negative electrode group can be reused in the same manner.

  In addition, when some of the positive electrodes have defects such as deterioration, only the defective positive electrodes can be easily replaced without affecting other positive electrodes, so a new laminated laminate battery Can be made and used. The negative electrode can be reused in the same manner.

  FIG. 1 is a schematic cross-sectional view showing a positive electrode group of the present invention.

  The positive electrode current collecting tab 4, the current collecting tab protection plate 9, and the positive electrode lead terminal 1 have holes to be inserted into the screw fixing rods 10. The positive electrode lead terminal 1 provided with the insulating resin 2 is inserted into the screw fixing rod 10. Next, the positive electrode current collector tab 4 having the current collector tab protection plates 9 on both sides is used as one set of positive electrodes, and four sets of positive electrodes are inserted to form a positive electrode group. Further, a washer 11 is inserted, and four sets of positive electrodes are fixed with screws 12. One or more positive electrodes may be used.

  The negative electrode group is prepared in the same manner as the positive electrode group.

  A positive electrode group, a negative electrode group, and a separator are combined, and a positive electrode and a negative electrode are stacked via the separator to produce an electrode laminate. Specifically, a separator, a negative electrode, a separator, a positive electrode, a separator,..., A separator, a positive electrode, a separator, a negative electrode, and a separator are laminated in this order. The four sides of the electrode laminate are fixed with an adhesive tape or the like and stored in a laminate case.

  When sealing the laminate case on the side having the positive electrode extraction terminal and the negative electrode extraction terminal, the sealing is performed at the position of the insulating resin. A part of the positive electrode extraction terminal and the negative electrode extraction terminal is drawn outside, and the three sides are heat-welded, and then an electrolyte is injected and heat-welded in vacuum to produce a laminated laminate battery.

  One set of positive electrodes may have a current collecting tab protection plate and a positive current collecting tab. That is, it is not always necessary to have the current collecting tab protection plate on both sides of the positive electrode current collecting tab, and it may be provided only on one side. However, the positive electrode current collecting tabs should not touch each other. The same applies to the negative electrode.

  In order to improve connection reliability, the screw fixing rod and the positive electrode lead terminal may be welded. The type of welding is preferably laser welding, resistance welding, or ultrasonic welding. The same applies to the negative electrode.

  The material of the current collecting tab protective plate of the positive electrode group and the fixing rod for screw or caulking fixing rod is preferably aluminum in terms of connection reliability, and the screw is also particularly preferably aluminum.

  The material of the current collector tab protective plate of the negative electrode group and the fixing rod for screw or caulking fixing rod is preferably copper or stainless steel in view of connection reliability, and the screw is particularly preferably copper or stainless steel.

  The outer peripheral shape of the current collecting tab protection plate is not particularly limited, but is preferably circular or elliptical in consideration of protecting the sandwiched current collecting tab. The thicknesses of the individual current collecting tab protection plates do not need to be the same because they are not for keeping the distance between the electrodes constant.

  The sizes of the individual current collecting tab protection plates do not need to be the same. Rather, it is preferable that the current collecting tab protective plates have different sizes in consideration of sandwiching and protecting the current collecting tabs.

  The positive electrode current collecting tab is for connecting the positive electrodes to each other and further connecting to a positive electrode lead terminal serving as an external electrode terminal. The positive electrode current collector tab preferably has the same thickness as the current collector when a positive electrode current collector is used. The same applies to the negative electrode current collecting tab.

  The separator is preferably a porous film having a three-layer structure of polypropylene or polypropylene / polyethylene / polypropylene.

  When reusing the positive electrode of the laminated laminate battery once assembled, the laminate case is cut, the negative electrode is removed by removing the screw from the screw fixing rod of the negative electrode group, and the positive electrode group and the separator are taken out. By assembling a new negative electrode group and using a new laminate case in the same manner as the first time, a laminated laminate battery can be obtained by reusing the positive electrode group as it is. Similarly, the negative electrode can be reused by removing the positive electrode.

  Not only can all the positive electrodes be reused, but some can also be reused. In order to reuse a part of the positive electrode, the laminate case is cut, the unnecessary positive electrode is removed by removing the screw from the screw fixing rod of the positive electrode group, and the positive electrode, separator, and negative electrode group to be reused are taken out. If a positive electrode group is newly reassembled by replenishing the positive electrode and then assembled in the same manner as the first time using a new laminate case, a laminated laminate battery in which a part of the positive electrode is reused can be obtained. Similarly, a part of the negative electrode can be reused.

  FIG. 2 is a schematic cross-sectional view showing a positive electrode group according to the second embodiment of the present invention. The caulking fixing rod 13 is for fixing four sets of positive electrodes and plays the same role as the screw fixing rod in FIG. The rest of the configuration is the same as in FIG.

  When reusing the positive electrode of a laminated battery once assembled, the laminate case is cut, the negative electrode is removed by cutting the caulking claw at the tip of the caulking fixing rod of the negative electrode group, and the positive electrode group and the separator are taken out. . By assembling a new negative electrode group using a new caulking fixing rod and assembling in the same manner as the first time using a new laminate case, a laminated laminate battery in which the positive electrode group is reused as it is can be obtained.

  Up to this point, mainly the positive electrode has been described, but the same can be applied to the negative electrode.

  Examples of the present invention are described in detail below.

A positive electrode active material of LiMn ₂ O ₄ that occludes and releases lithium ions is applied to a positive electrode current collector made of aluminum foil, except on the positive electrode current collector tab drawn from the positive electrode current collector to form a positive electrode. did. Further, on the negative electrode current collector made of copper foil, except for the negative electrode current collector tab drawn out from the negative electrode current collector, a negative electrode active material of graphite that occludes and releases lithium ions was applied to form a negative electrode. .

  The current collecting tab protective plate, screw fixing rod and screw of the positive electrode group were made of aluminum, and the current collecting tab protective plate, screw fixing rod and screw of the negative electrode group were made of copper.

  After preparing the positive electrode group and the negative electrode group, the positive electrode from which the four positive electrode current collecting tabs were drawn and the negative electrode from which the five negative electrode current collecting tabs were drawn were laminated via a separator to form an electrode laminate. Produced.

  The positive electrode lead terminal was made of aluminum having a width of 10 mm and a thickness of 0.2 mm, and the positive electrode current collecting tab was 10 mm in width, 0.02 mm in thickness, and 15 mm in length. The negative electrode lead terminal was made of nickel having a width of 10 mm and a thickness of 0.2 mm, and the negative electrode current collecting tab had a width of 10 mm, a thickness of 0.02 mm, and a length of 15 mm. The electrode laminate is housed in a laminate case, covered with an insulating resin with a thickness of 0.1 mm on the positive electrode lead terminal and the negative electrode lead terminal, and thermally welded so that the welding position of the laminate case overlaps the insulating resin. A part of the lead terminal and the negative electrode lead terminal was pulled out, the electrolyte was put, and heat welding was performed in a vacuum to produce a laminated laminate battery.

  After using the laminated laminate battery, in order to reuse the positive electrode, the laminated case of the used laminated battery was cut and the positive electrode group was taken out. A new laminated laminate battery was fabricated using a new negative electrode group and a laminate case.

  It was confirmed that the manufactured laminated battery had design characteristics and safety including the initial capacity. It was confirmed that it is possible to provide a laminated laminate battery having a structure in which a battery once assembled and disassembled can be disassembled and the positive electrode group can be reused as it is.

(Example 2)
A laminated laminate battery was produced in the same manner as in Example 1 except that the screw fixing rod was a caulking fixing rod. In Example 1, the positive electrode current collecting tab was fixed with a screw, but in Example 2, it was fixed with caulking.

  After using the laminated laminate battery, in order to reuse the positive electrode, the laminated case of the used laminated battery was cut and the positive electrode group was taken out. A new negative electrode group was prepared using a new caulking fixing rod, and a new laminated laminate battery was prepared using a laminate case.

  It was confirmed that the manufactured laminated battery had design characteristics and safety including the initial capacity. It was confirmed that it is possible to provide a laminated laminate battery having a structure in which a battery once assembled and disassembled can be disassembled and the positive electrode group can be reused as it is.

(Example 3)
Of the positive electrodes from which the four positive electrode current collecting tabs were drawn, one positive electrode was replaced with a new positive electrode, and the negative electrode group was used as it was without replacing with a new negative electrode. A laminated laminate battery was produced.

  A laminated laminate battery was used for about 3 hours. Thereafter, in order to reuse the positive electrode, the laminate case of the laminated laminate battery was cut and the positive electrode group was taken out. The screws were removed, one of the positive electrodes was replaced with a new positive electrode, and the positive electrode group was assembled again. The negative electrode group was reused as it was, and a new laminated battery was produced using a new laminate case.

  It was confirmed that the produced laminated laminate had design characteristics and safety including the initial capacity. It was confirmed that it was possible to provide a laminated laminate battery having a structure in which a battery once assembled and disassembled was disassembled and a part of the positive and negative electrode groups could be reused as they were.

  From the description of the examples, it was confirmed that it is possible to provide a laminated battery having a structure in which a battery once assembled and used can be disassembled and the positive electrode or the negative electrode can be reused as it is.

  The embodiments of the present invention have been described above using the embodiments. However, the present invention is not limited to these embodiments, and the present invention is not limited to the scope of the present invention. Included in the invention. That is, various changes and modifications that can be naturally made by those skilled in the art are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 Positive electrode extraction terminal 2 Insulation resin 3 Welding part 4 Positive electrode current collection tab 5 Negative electrode extraction terminal 6 Welding part 7 Negative electrode current collection tab 8 Battery element laminated part 9 Current collection tab protection board 10 Screw fixing rod 11 Washer 12 Screw 13 For caulking Fixed rod 14 positive electrode

Claims (6)

  A positive electrode having a positive electrode current collecting tab and a negative electrode having a negative electrode current collecting tab were connected to the positive electrode current collecting tab and the negative electrode current collecting tab of the electrode laminate laminated via a separator. A laminated laminate battery in which a part of a negative electrode lead-out terminal is pulled out and stored in a laminate outer package, and is a current collector arranged in contact with the positive electrode current collector tab having the positive electrode and the positive electrode current collector tab A positive electrode group element having a tab protective plate and the positive electrode lead terminal, a negative electrode current collecting tab having the negative electrode, a current collecting tab protective plate arranged in contact with the negative electrode current collector tab, and a negative electrode having the negative electrode lead terminal A laminated laminate battery, wherein a fixing rod is inserted into a hole provided in at least one of the group elements, and the fixing rod is further inserted into a washer and fixed.   2. The laminated laminate battery according to claim 1, wherein the fixing rod is a screw fixing rod or a caulking fixing rod.   The laminated laminate battery according to claim 1 or 2, wherein the positive electrode lead terminal and the screw fixing bar or the caulking fixing bar are welded.   The material for the current collecting tab protection plate and the screw fixing rod or the caulking fixing rod is aluminum in the positive electrode group and copper or stainless steel in the negative electrode group. The laminated laminate battery according to any one of the above.   The material of the current collecting tab protection plate and the screw fixing rod and the screw or the caulking fixing rod is aluminum in the positive electrode group and copper or stainless steel in the negative electrode group. Item 5. The laminated laminate battery according to any one of Items 1 to 4.   The laminated laminate battery according to any one of claims 3 to 5, wherein the welding is laser welding, resistance welding, or ultrasonic welding.

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