JP2010027414A - Manufacturing method for battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance a battery characteristic in a battery layered alternately with a plurality of positive electrode plates and negative electrode plates, while interposing a separator therebetween. <P>SOLUTION: This manufacturing method for the battery manufactures the battery layered alternately with a plurality of positive electrode members comprising a positive active material and a collector, and a plurality of negative electrode members comprising a negative active material and a collector, while interposing a separator member therebetween. In the method, the plurality of positive electrode members is selected into positive electrode member mass ranks of mass ranges, with respective masses of the measured positive electrode members belonging thereto; the plurality of negative electrode members is selected into negative electrode member mass ranks of mass ranges with respective masses of the measured negative electrode members belonging thereto, and the plurality of positive electrode members and negative electrode members are layered, while making the separator member interpose therebetween, to position a mass order of the positive electrode member masses with the respective positive electrode members belonging thereto to get higher, and to position a mass order of the negative electrode member masses, with the respective negative electrode members belonging thereto so that is higher, along with a prescribed layered direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention generally relates to a method for manufacturing a battery, and more particularly, to a method for manufacturing a battery having a plurality of positive electrode members and negative electrode members alternately stacked between separators.

  In recent years, batteries, particularly secondary batteries, have been used as power sources for portable electronic devices such as mobile phones and portable personal computers. As an example of a secondary battery, a lithium ion secondary battery is known to have a relatively large energy density.

For example, Japanese Patent Laying-Open No. 2005-116482 (Patent Document 1) describes a configuration of a thin battery as a lithium ion secondary battery. In this thin battery, a power generation element having a positive electrode plate and a negative electrode plate alternately stacked between separators is accommodated in an exterior member and sealed, and is connected to the power generation element via a plurality of current collectors And the negative terminal is led out from the outer peripheral edge of the exterior member. In such a stacked secondary battery, a plurality of positive plates and negative plates are alternately stacked in the exterior member with separators interposed therebetween.
JP-A-2005-116482

  By the way, there are variations in the mass of each of the stacked positive and negative electrode plates due to manufacturing tolerances. For example, when an electrode plate is manufactured by a coating method, the positive electrode plate is configured by forming the positive electrode active material on the surface of the current collector, and the negative electrode plate is formed by forming the negative electrode active material on the surface of the current collector. It is composed by doing. The variation in the mass of the current collector is sufficiently small compared to the variation in the mass of the positive electrode active material layer or the negative electrode active material layer formed on the surface of the current collector. , Depending on variations in mass of the positive electrode active material layer or the negative electrode active material layer formed on the surface of the current collector.

  If there are variations in the mass of each of the stacked positive electrode plates and negative electrode plates, for example, as the combination of the opposing positive electrode plate and negative electrode plate, the heaviest positive electrode plate and heaviest material within the manufacturing tolerance of mass Combinations such as a negative electrode plate, the lightest positive electrode plate and the lightest negative electrode plate, the heaviest positive electrode plate and the lightest negative electrode plate, the lightest positive electrode plate and the heaviest negative electrode plate, etc. are conceivable. At this time, since the variation in the mass of the current collector is sufficiently small, the mass ratio of the negative electrode active material layer to the positive electrode active material layer formed on each opposed surface varies between each pair of the positive electrode plate and the negative electrode plate facing each other. become.

  The charge / discharge reaction is performed on the opposing surfaces of the plurality of stacked positive and negative electrode plates. According to the inventor's knowledge, in a battery in which the mass ratio of the negative electrode active material layer to the positive electrode active material layer formed on each facing surface varies, battery characteristics such as capacity retention rate (cycle life) are deteriorated. There is.

  Accordingly, an object of the present invention is to improve battery characteristics in a battery in which a plurality of positive plates and negative plates are alternately stacked with separators interposed therebetween.

  According to the battery manufacturing method of the present invention, a plurality of positive electrode members made of a positive electrode active material and a current collector and a plurality of negative electrode members made of a negative electrode active material and a current collector are interposed with a separator member therebetween. In the manufacturing method of the battery laminated | stacked alternately, the following steps are provided.

  (A) A step of creating a plurality of positive member mass ranks ranked in order of mass so that each has a predetermined mass range.

  (B) creating a plurality of negative member mass ranks ranked in order of mass so that each has a predetermined mass range;

  (C) measuring a mass of each of the plurality of positive electrode members, and selecting the plurality of positive electrode members in a positive electrode member mass rank in a mass range to which each mass of the measured positive electrode members belongs.

  (D) measuring the mass of each of the plurality of negative electrode members, and selecting the plurality of negative electrode members in the negative electrode member mass rank in the mass range to which each mass of the measured negative electrode member belongs.

  (E) The mass rank of the negative electrode member mass rank to which each of the plurality of negative electrode members belongs is set so that the mass rank of the positive electrode member mass rank to which each of the plurality of positive electrode members belongs is increased along the predetermined stacking direction. A step of alternately laminating a plurality of positive electrode members and negative electrode members with a separator member interposed therebetween so as to be higher.

  In the battery manufacturing method of the present invention, the plurality of positive electrode members are stacked such that the mass rank of the positive electrode member mass rank to which each of the plurality of positive electrode members belongs is increased along the predetermined stacking direction. Is laminated so that the mass rank of the negative electrode member mass rank to which each of the plurality of negative electrode members belongs is increased along the predetermined lamination direction, and in each of the opposing positive electrode member and negative electrode member, Variation in the mass ratio of the negative electrode active material to the positive electrode active material on the opposing surface can be reduced. Thereby, since the charging / discharging reaction performed by each opposing surface of the some positive electrode member and negative electrode member to laminate | stack progresses substantially uniformly, a capacity | capacitance maintenance factor (cycle life) can be improved. Moreover, the safety | security in the case of assuming misuse, such as an overcharge state, can be improved.

  As described above, according to the present invention, in a battery in which a plurality of positive electrode members and negative electrode members are alternately stacked with separator members interposed therebetween, the capacity retention rate (cycle life) can be improved. Safety in an overcharged state can be improved.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic plan view showing an example of a non-aqueous electrolyte battery as one embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view as seen from the direction along the line II-II in FIG. FIG. 3 is a partial cross-sectional view, and FIG. 3 is a partial cross-sectional view showing, in an enlarged manner, a cross section viewed from the direction along line III-III in FIG.

  As shown in FIG. 1, the battery 100 includes a power generation element 10, an exterior member 20 that houses and seals the power generation element 10, and is connected to the power generation element 10 via a plurality of current collectors. It consists of a positive electrode terminal 30 and a negative electrode terminal 40 which are led out from the outer periphery.

  As shown in FIG. 2 and FIG. 3, the power generation element 10 includes a plurality of positive electrode members 11, a plurality of negative electrode members 12, each between a plurality of positive electrode members 11 and a plurality of negative electrode members 12. It includes a plurality of separator members 13 disposed so as to intervene and a non-aqueous electrolyte (not shown). Each of the plurality of positive electrode members 11 and each of the plurality of negative electrode members 12 are alternately stacked with each of the plurality of separator members 13 interposed therebetween. The positive electrode member 11, the negative electrode member 12, and the separator member 13 are formed in a plate shape, a film shape, a foil shape, or the like. For example, a laminate in which a plurality of film-like positive electrode members 11 and negative electrode members 12 are laminated in close contact with each other via a separator member 13 is filled in an exterior member 20 made of an aluminum laminate film. As shown in FIG. 3, the plurality of negative electrode members 12 are connected to the negative electrode terminal 40 via the plurality of current collecting members 41. Although not shown in figure, the some positive electrode member 11 is similarly connected to the positive electrode terminal 30 (FIG. 1).

  According to the method for manufacturing a battery of the present invention, when a plurality of positive electrode members 11 and negative electrode members 12 are alternately stacked with separator members 13 interposed therebetween, in one embodiment of the present invention, the manufactured battery 100 Is configured as follows.

  The plurality of positive electrode members 11 have a higher mass rank of the positive electrode member mass rank to which each of the plurality of positive electrode members 11 belongs along the predetermined stacking direction, and in the direction from the top to the bottom in FIGS. 2 and 3. Are stacked. Specifically, in the example shown in FIG. 2 and FIG. 1 to 17, the positive electrode member mass ranks to which each of the plurality of positive electrode members 11 belong are stacked such that the mass rank is higher.

  The plurality of negative electrode members 12 have a mass rank of a negative rank member mass rank to which each of the plurality of negative electrode members 12 belongs along the predetermined stacking direction, and in the direction from the top to the bottom in FIGS. 2 and 3. They are stacked so as to be higher. Specifically, in the example shown in FIG. 2 and FIG. 1 to 18, the negative electrode member mass rank to which each of the plurality of negative electrode members 12 belongs is stacked so as to have a higher mass rank.

  In addition, according to the method for manufacturing a battery of the present invention, a plurality of positive electrode members 11 and negative electrode members 12 are alternately stacked with separator members 13 interposed therebetween. The battery 100 is configured as follows.

  The plurality of positive electrode members 11 are stacked so that the mass of each of the positive electrode members 11 is increased along a predetermined stacking direction, and in a direction from top to bottom in FIGS. 2 and 3. Specifically, in the example shown in FIG. 2 and FIG. It is laminated so as to increase the mass according to 1-17. In this case, the stacking order No. 1-17 itself corresponds to a positive electrode member mass rank.

  The plurality of negative electrode members 12 are stacked so that the mass of each of the negative electrode members 12 is increased along a predetermined stacking direction, and in a direction from top to bottom in FIGS. 2 and 3. Specifically, in the example shown in FIG. 2 and FIG. It is laminated so that the mass increases according to 1-18. In this case, the stacking order No. 1-18 itself corresponds to a negative electrode member mass rank.

  The positive electrode member 11 is configured by forming a positive electrode active material layer on the surface of the current collector. The negative electrode member 12 is configured by forming a negative electrode active material layer on the surface of the current collector.

  In the battery 100 of the present invention, the plurality of positive electrode members 11 are stacked so that the mass rank of the positive electrode member mass rank to which each of the plurality of positive electrode members 11 belongs is increased along the predetermined stacking direction. 12 are stacked so that the mass rank of the negative electrode member mass rank to which each of the plurality of negative electrode members 12 belongs is increased along the predetermined stacking direction. Therefore, each pair of the positive electrode member 11 and the negative electrode member facing each other is stacked. 12, the variation in the mass ratio of the negative electrode active material to the positive electrode active material on each facing surface can be reduced. As a result, the charge / discharge reaction performed on the opposing surfaces of the plurality of stacked positive electrode members 11 and negative electrode members 12 proceeds substantially uniformly, so that the capacity retention rate (cycle life) can be improved. Moreover, the safety | security in the case of assuming misuse, such as an overcharge state, can be improved.

  For example, the positive electrode member 11 is formed by applying a positive electrode mixture containing a positive electrode active material, a binder, and a conductive additive onto the surface of a current collector made of aluminum foil, and drying the positive electrode active material layer. It is produced by forming on the surface of a current collector.

  In general, as the positive electrode active material, a metal oxide, a metal sulfide, or a specific polymer can be used depending on the type of the target battery.

When constituting a lithium ion secondary battery, metal sulfides or oxides such as TiS ₂ , MoS ₂ , NbSe ₂ , V ₂ O ₅ can be used as the positive electrode active material. In addition, LiM _x O ₂ (in the chemical formula, M represents one or more transition metals, x varies depending on the charge / discharge state of the battery, and is usually 0.05 or more and 1.10 or less as a positive electrode active material of the lithium ion secondary battery. Lithium composite oxide mainly composed of As the transition metal M constituting this lithium composite oxide, Co, Ni, Mn and the like are preferable. Specific examples of such a lithium composite oxide include LiCoO ₂ , LiNiO ₂ , LiNi _y Co _1-y O ₂ (where 0 <y <1), Li _{1 + a} (Ni _x Co _y Mn _z ) O. _2-b (in the chemical formula, −0.1 <a <0.2, x + y + z = 1, −0.1 <b <0.1), LiMn ₂ O _{4 and the} like. These lithium composite oxides can generate a high voltage and become a positive electrode active material having an excellent energy density. In order to produce the positive electrode member 11, a plurality of these positive electrode active materials may be used in combination.

  Moreover, as a binder contained in said positive electrode mixture, the well-known binder normally used for the positive electrode mixture of a battery can be used, A conductive agent is used for said positive electrode mixture. For example, known additives can be added.

  For example, in the negative electrode member 12, a negative electrode mixture containing a negative electrode active material and a binder is uniformly applied on the surface of a current collector made of copper foil and dried to collect the negative electrode active material layer. It is made by forming on the surface of the body.

When constituting a lithium secondary battery, it is preferable to use a material capable of doping and dedoping lithium as the negative electrode active material. As a material that can be doped or dedoped with lithium, for example, a carbon material such as a non-graphitizable carbon material or a graphite material can be used. Specifically, carbon materials such as pyrolytic carbons, cokes, graphites, glassy carbon fibers, organic polymer compound fired bodies, carbon fibers, and activated carbon can be used. Examples of the cokes include pitch coke, needle coke, and petroleum coke. Moreover, said organic polymer compound fired body means what carbonized by baking a phenol resin, furan resin, etc. at a suitable temperature. In addition to the carbon material described above, as a material that can be doped or dedoped with lithium, a polymer such as polyacetylene or polypyrrole, or an oxide such as SnO ₂ or Li ₄ Ti ₅ O ₁₂ (lithium titanate) can also be used. .

  Moreover, as a binder contained in said negative electrode mixture, the well-known binder normally used for the negative electrode mixture of a lithium ion battery can be used, In said negative electrode mixture, Known additives and the like can be added.

The nonaqueous electrolytic solution is prepared by dissolving an electrolyte in a nonaqueous solvent. As the electrolyte, for example, a solution obtained by dissolving LiPF ₆ at a concentration of 1.0 mol / L in a non-aqueous solvent is used. As an electrolyte other than LiPF ₆ , lithium salts such as LiBF ₄ , LiAsF ₆ , LiClO ₄ , LiCF ₃ SO ₃ , LiN (SO ₂ CF ₃ ) ₂ , LiC (SO ₂ CF ₃ ) ₃ , LiAlCl ₄ , LiSiF ₆ are used. Can be mentioned. Among these, it is desirable from the viewpoint of oxidation stability that LiPF ₆ or LiBF ₄ is particularly used as the electrolyte. Such an electrolyte is preferably used by being dissolved in a nonaqueous solvent at a concentration of 0.1 mol / L to 3.0 mol / L, and dissolved at a concentration of 0.5 mol / L to 2.0 mol / L. More preferably, it is used. As the non-aqueous solvent, for example, a mixture of propylene carbonate, ethylene carbonate, and diethyl carbonate at a volume ratio of 5-20: 20-30: 60-70 is used. Other non-aqueous solvents include: cyclic carbonates such as propylene carbonate and ethylene carbonate; chain carbonates such as diethyl carbonate and dimethyl carbonate; carboxylic acid esters such as methyl propionate and methyl butyrate; γ-butyllactone, sulfolane, Ethers such as 2-methyltetrahydrofuran and dimethoxyethane can be used. These non-aqueous solvents may be used alone or in combination of two or more. Among these, it is preferable from the point of oxidation stability to use carbonate ester as a non-aqueous solvent.

  In the above-described embodiment, one separator member is interposed between the positive electrode member and the negative electrode member, but a plurality of separator members may be interposed. The material of the plurality of separator members may be the same or different.

  In the above embodiment, a plurality of strip-shaped separator members are used as the separator member in the same manner as the positive electrode member and the negative electrode member. However, the separator member may be long. In that case, the separator member is folded into ninety nines so that the positive electrode member and the negative electrode member are interposed between the separator members, or the separator member is wound into a square shape having a flat portion and the positive electrode member is interposed between the separator members. And a negative electrode member may be interposed. At this time, a plurality of separator members may be folded or wound.

  A nonaqueous electrolyte battery 100 as shown in FIGS. 1 to 3 was produced as follows.

The plate-like positive electrode member (positive electrode plate) 11 is made of a positive electrode mixture containing LiCoO ₂ as a positive electrode active material, polyvinylidene fluoride (PVdF) as a binder, and acetylene black as a conductive additive. The positive electrode active material layer was formed on the surface of the current collector by applying it on the surface of the current collector made of aluminum foil and drying it. At this time, an end portion of the aluminum foil as a current collector was provided with a portion where the surface of the aluminum foil was exposed without applying the positive electrode mixture.

  A plate-like negative electrode member (negative electrode plate) 12 is a current collector made of a copper foil containing a negative electrode mixture containing a graphite-based material as a negative electrode active material and polyvinylidene fluoride (PVdF) as a binder. The negative electrode active material layer was formed on the surface of the current collector. Under the present circumstances, the part which the surface of the copper foil exposed was provided in the edge part of the copper foil as an electrical power collector, without apply | coating a negative mix.

  The positive electrode member 11 and the negative electrode member 12 obtained as described above were brought into close contact with each other via a separator member 13 made of, for example, a microporous polyethylene film, and a laminate was formed by laminating a large number of sheets.

  Then, in the laminate obtained above, the exposed portions of the aluminum foil in the plurality of positive electrode members 11 are superposed on the positive terminal 30 and ultrasonically welded to the positive electrode terminal 30, and the exposed portions of the copper foil in the plurality of negative electrode members 12 are overlapped. The terminal 40 was ultrasonically welded.

  Next, an aluminum laminated film in which an outer protective layer made of resin, an intermediate gas barrier layer made of aluminum, and an inner adhesive layer made of resin were laminated and integrated was produced. The above laminate was housed inside the exterior member 20 made of this aluminum laminate film. Thereafter, a part of the outer periphery of the exterior member 20 was left open in order to use it as an electrolyte inlet, and the other outer periphery of the exterior member 20 was thermally welded.

Then, a nozzle was inserted from the electrolyte solution injection port, and a nonaqueous electrolyte solution was injected into the battery 100. The non-aqueous electrolyte was prepared by dissolving the electrolyte in a non-aqueous solvent. As the electrolyte, a solution obtained by dissolving LiPF ₆ at a concentration of 1.0 mol / L in a non-aqueous solvent was used. As the non-aqueous solvent, a mixture of propylene carbonate, ethylene carbonate, and diethyl carbonate at a volume ratio of 5:25:70 was used.

  Next, a part of the outer periphery used as the electrolyte solution inlet is temporarily sealed, and after initial charging under predetermined conditions, the temporary sealing is opened again, and heat sealing is performed while reducing the pressure, and then the main seal is sealed. Stopped.

  In this manner, ten non-aqueous electrolyte batteries 100 (Sample Nos. 1 to 10) of Examples 1 and 2 and Comparative Example of the present invention were produced.

Example 1
In the above configuration, in the nonaqueous electrolyte battery 100 of Example 1, as shown in FIGS. 2 and 3, 17 (No. 1 to No. 17) positive electrode members 11 and 18 (No. 1 to No. 1). No. 18) negative electrode member 12 was laminated to produce a battery with a capacity of 4 Ah. At this time, the mass of each of the positive electrode member 11 and the negative electrode member 12 of Example 1 was measured with a measuring instrument.

  Table 1 shows the maximum value, the minimum value, the center value, the average value, and the standard deviation of the mass of the positive electrode member 11 and the negative electrode member 12 used in all the samples of the battery of Example 1.

  As shown in FIG. 2 and FIG. 1-No. The negative electrode member 12 is laminated in the order of lamination No. 1-No. 18 was laminated so as to increase the mass. In this case, the stacking order No. 1 to 17 themselves correspond to the positive electrode member mass rank. 1-18 itself corresponds to a negative electrode member mass rank.

  The masses of the positive electrode member 11 from the first sheet (No. 1) to the 17th sheet (No. 17) measured before lamination are shown in FIGS. In FIG. 4, the stacking order No. for all 10 samples of Example 1 is shown. 1-No. 17 and the respective masses of the positive electrode member 11 are shown. In FIG. 1-No. The relationship between 17 and each mass of the positive electrode member 11 is shown.

  Moreover, the mass of the negative electrode member 12 from the 1st sheet | seat (No. 1) measured before lamination | stacking to the 18th sheet | seat (No. 18) is shown in FIG. 6 and FIG. In FIG. 6, the stacking order No. for all 10 samples of Example 1 is shown. 1-No. 18 and the respective masses of the negative electrode member 12 are shown. In FIG. 1-No. The relationship between 18 and each mass of the negative electrode member 12 is shown.

  As shown in FIGS. 2 and 3, 17 positive electrode members 11 and 18 negative electrode members 12 are laminated with a separator member 13 interposed therebetween, that is, negative electrode / separator / positive electrode / separator / negative electrode / separator / When stacked in the order of positive electrode... Negative electrode / separator / positive electrode / separator / negative electrode, there are 34 positive and negative electrode facing surfaces corresponding to the number of front and back surfaces of the positive electrode member 11. For each of the 34 positive and negative electrode facing surfaces, the ratio (AC ratio) of the negative electrode active material layer mass to the positive electrode active material layer mass was measured. In addition, it is assumed that the mass of each aluminum foil used as each collector of the positive electrode member 11 of Example 1 is equal, and the mass of each copper foil used as each collector of the negative electrode member 12 is equal. Assumed. In addition, since the active material of the front and back of a collector cannot isolate | separate and measure a weight, the positive electrode active material layer mass and the negative electrode active material layer mass were computed on the collector front and back being equivalently applied.

  The positive and negative electrode facing surfaces of the 34th surface are arranged in the order of distance No. 1-No. 34, the inter-electrode order No. 1-No. The relationship between 34 and the AC ratio is shown in FIGS. In FIG. 1-No. 34 and the AC ratio. In FIG. 1-No. 34 shows the relationship between AC and AC ratio.

(Example 2)
In the above configuration, in the nonaqueous electrolyte battery 100 of Example 2, as shown in FIGS. 2 and 3, 17 (No. 1 to No. 17) positive electrode members 11 and 18 (No. 1 to No. 1). No. 18) negative electrode member 12 was laminated to produce a battery with a capacity of 4 Ah. At this time, the mass of each of the positive electrode member 11 and the negative electrode member 12 of Example 2 was measured with a measuring instrument.

  Table 2 shows the maximum value, minimum value, center value, average value, and standard deviation of the masses of the positive electrode member 11 and the negative electrode member 12 used in all the samples of the battery of Example 2.

  In Example 2, a plurality of positive member mass ranks ranked in order of mass so that each had a predetermined mass range was created as shown in Table 3.

  Moreover, as shown in Table 4, a plurality of negative electrode member mass ranks ranked in order of mass so that each has a predetermined mass range.

  First, a plurality of positive electrode members 11 were selected in the positive electrode member mass ranks A to E (Table 3) in the mass range to which the respective masses of the positive electrode members 11 measured above belong.

  Next, the plurality of negative electrode members 12 were sorted into the negative electrode member mass ranks A to E (Table 4) in the mass range to which the respective masses of the negative electrode members 12 measured above belong.

  As shown in FIGS. 2 and 3, the positive electrode member 11 has the stacking order No. 1-No. 17, the positive electrode member mass rank to which each of the plurality of positive electrode members 11 belongs is stacked so that the mass rank thereof increases from A to E. 1-No. 18, the negative electrode member mass rank to which each of the plurality of negative electrode members 12 belonged was stacked so that the mass rank increased from A to E. For example, in sample number 1 of Example 2, the stacking order No. 1-No. The mass of the positive electrode member 11 laminated according to 17 and the positive electrode member mass rank to which the mass belongs are shown in order as follows. [] Indicates the mass value (g), and [] indicates the rank (A to E) to which the mass value belongs. Stacking order No. 1-No. 17, 2.642 [B], 2.2697 [C], 2.2688 [C], 2.2677 [C], 2.267 [C], 2.268 [C], 2.2681 [C ], 2.2688 [C], 2.271 [D], 2.274 [D], 2.2717 [D], 2.2723 [D], 2.2718 [D], 2.2715 [D] , 2.2738 [D], 2.2761 [E], 2.27779 [E]. Thus, in sample number 1 of Example 2, the stacking order No. 1-No. 17, 17 positive electrode members 11 were laminated so that the mass rank of the positive electrode member mass rank to which each of the positive electrode members 11 belonged increased from B to E. However, within the same rank, for example within the D rank, the masses are 2.271 [D], 2.274 [D], 2.2717 [D], 2.2723 [D], 2.2718 [D], The masses are not increased or decreased in the order of lamination, ie, 2.2715 [D] and 2.2738 [D], and are random.

  The mass of the positive electrode member 11 from the first sheet (No. 1) to the 17th sheet (No. 17) measured before lamination is shown in FIGS. In FIG. 10, the stacking order No. for all 10 samples of Example 2 is shown. 1-No. 17 and the respective masses of the positive electrode member 11 are shown. In FIG. 1-No. The relationship between 17 and each mass of the positive electrode member 11 is shown.

  Moreover, the mass of the negative electrode member 12 from the 1st sheet (No. 1) to the 18th sheet (No. 18) measured before lamination is shown in FIGS. In FIG. 12, the stacking order No. for all 10 samples of Example 2 is shown. 1-No. 18 and the respective masses of the negative electrode member 12 are shown. In FIG. 1-No. The relationship between 18 and each mass of the negative electrode member 12 is shown.

  As shown in FIGS. 2 and 3, 17 positive electrode members 11 and 18 negative electrode members 12 are laminated with a separator member 13 interposed therebetween, that is, negative electrode / separator / positive electrode / separator / negative electrode / separator / When stacked in the order of positive electrode... Negative electrode / separator / positive electrode / separator / negative electrode, there are 34 positive and negative electrode facing surfaces corresponding to the number of front and back surfaces of the positive electrode member 11. For each of the 34 positive and negative electrode facing surfaces, the ratio (AC ratio) of the negative electrode active material layer mass to the positive electrode active material layer mass was measured. In addition, it is assumed that the mass of each aluminum foil used as each collector of the positive electrode member 11 of Example 2 is equal, and the mass of each copper foil used as each collector of the negative electrode member 12 is equal. Assumed. In addition, since the active material of the front and back of a collector cannot isolate | separate and measure a weight, the positive electrode active material layer mass and the negative electrode active material layer mass were computed on the collector front and back being equivalently applied.

  The positive and negative electrode facing surfaces of the 34th surface are arranged in the order of distance No. 1-No. 34, the inter-electrode order No. 1-No. FIG. 14 and FIG. 15 show the relationship between 34 and the AC ratio. In FIG. 1-No. 34 and the AC ratio. In FIG. 1-No. 34 shows the relationship between AC and AC ratio.

(Comparative example)
In the nonaqueous electrolyte battery 100 of the comparative example, 17 (No. 1 to No. 17) positive electrode members 11 and 18 (No. 1 to No. 18) negative electrode members 12 randomly selected are stacked. A battery with a capacity of 4 Ah was produced. At this time, the mass of each of the positive electrode member 11 and the negative electrode member 12 of the comparative example was measured.

  Table 5 shows the maximum value, the minimum value, the center value, the average value, and the standard deviation of the mass of the positive electrode member 11 and the negative electrode member 12 used in all the samples of the battery of the comparative example.

  The mass of the positive electrode member 11 from the first sheet (No. 1) to the 17th sheet (No. 17) measured before lamination is shown in FIGS. In FIG. 16, the stacking order No. for all 10 samples of the comparative examples is shown. 1-No. 17 and the respective masses of the positive electrode member 11 are shown. In FIG. 1-No. The relationship between 17 and each mass of the positive electrode member 11 is shown.

  Moreover, the mass of the negative electrode member 12 from the 1st sheet (No. 1) to the 18th sheet (No. 18) measured before lamination is shown in FIGS. In FIG. 18, the stacking order No. for all 10 samples of the comparative examples. 1-No. 18 and the respective masses of the negative electrode member 12 are shown. In FIG. 1-No. The relationship between 18 and each mass of the negative electrode member 12 is shown.

  Also in the comparative example, in the same manner as in Examples 1 and 2, the ratio of the negative electrode active material layer mass to the positive electrode active material layer mass (AC ratio) was measured for each of the 34 positive and negative electrode facing surfaces. It is assumed that the mass of each aluminum foil used as each current collector of the positive electrode member 11 is equal, and the mass of each copper foil used as each current collector of the negative electrode member 12 is equal. The positive electrode active material layer mass and the negative electrode active material layer mass were calculated.

  The positive and negative electrode facing surfaces of the 34th surface are arranged in the order of distance No. 1-No. 34, the inter-electrode order No. 1-No. The relationship between 34 and the AC ratio is shown in FIGS. In FIG. 20, all the 10 samples in the comparative example are ordered in the inter-electrode order No. 1-No. 34 and the AC ratio, and in FIG. 1-No. 34 shows the relationship between AC and AC ratio.

  Comparing FIGS. 8 to 9 and FIGS. 20 to 21, in each sample of the example, the ratio (AC ratio) of the negative electrode active material layer mass to the positive electrode active material layer mass on each positive and negative electrode facing surface is a comparative example. It can be seen that the variation is small compared to the AC ratio.

  Using each of the 10 batteries of Examples 1 and 2 and Comparative Example produced as described above, a charge / discharge cycle test was performed under the following conditions.

(Test conditions)
Charging: Start at 4A / 4.2V, until the end current reaches 0.04A Pause: 10 minutes Discharge: Start at 4A, until 2.7V Number of cycles: 500 cycles Perform 500 cycles of charge / discharge cycle test After that, the capacity retention rate at 4A was calculated. The capacity retention rate was determined by dividing the ratio of the discharge capacity after 500 cycles to the initial capacity at 100 minutes. The results are shown in Table 6.

  As is apparent from the results in Table 6, the average value of the capacity retention rates of the batteries of the comparative examples is about 81%, whereas the average value of the capacity maintenance rates of the batteries of Examples 1 and 2 is about According to the present invention, in a battery in which a plurality of positive electrode members and negative electrode members are alternately stacked with separator members interposed therebetween, the capacity retention rate (cycle life) is improved. It can be seen that it can be improved.

  It should be considered that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above embodiments and examples but by the scope of claims, and is intended to include all modifications and variations within the meaning and scope equivalent to the scope of claims. .

  The battery manufactured according to the manufacturing method of the present invention can be used as a power source for portable electronic devices such as a mobile phone and a portable personal computer, a power source for automobiles, and the like.

1 is a schematic plan view showing an example of a non-aqueous electrolyte battery as one embodiment of the present invention. It is a fragmentary sectional view which expands and shows the cross section seen from the direction along the II-II line of FIG. It is a fragmentary sectional view which expands and shows the cross section seen from the direction along the III-III line of FIG. For all 10 samples of Example 1 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 17 and each mass of a positive electrode plate. For each of sample numbers 1 to 10 of Example 1 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 17 and each mass of a positive electrode plate. For all 10 samples of Example 1 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 18 and each mass of a negative electrode plate. For each of sample numbers 1 to 10 of Example 1 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 18 and each mass of a negative electrode plate. For all 10 samples of Example 1 of the present invention, the inter-electrode order No. 1-No. It is a figure which shows the relationship between 34 and AC ratio. For each of sample numbers 1 to 10 of Example 1 of the present invention, the inter-electrode order No. 1-No. It is a figure which shows the relationship between 34 and AC ratio. For all 10 samples of Example 2 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 17 and each mass of a positive electrode plate. For each of sample numbers 1 to 10 of Example 2 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 17 and each mass of a positive electrode plate. For all 10 samples of Example 2 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 18 and each mass of a negative electrode plate. For each of sample numbers 1 to 10 of Example 2 of the present invention, the stacking order No. 1-No. It is a figure which shows the relationship between 18 and each mass of a negative electrode plate. For all 10 samples of Example 2 of the present invention, the inter-electrode order No. 1-No. It is a figure which shows the relationship between 34 and AC ratio. For each of sample numbers 1 to 10 of Example 2 of the present invention, the inter-electrode order No. 1-No. It is a figure which shows the relationship between 34 and AC ratio. For all 10 samples of the comparative examples, the stacking order No. 1-No. It is a figure which shows the relationship between 17 and each mass of a positive electrode plate. For each sample number 1 to 10 in the comparative example, the stacking order No. 1-No. It is a figure which shows the relationship between 17 and each mass of a positive electrode plate. For all 10 samples of the comparative examples, the stacking order No. 1-No. It is a figure which shows the relationship between 18 and each mass of a negative electrode plate. For each sample number 1 to 10 in the comparative example, the stacking order No. 1-No. It is a figure which shows the relationship between 18 and each mass of a negative electrode plate. For all 10 samples of the comparative examples, the inter-electrode order No. 1-No. It is a figure which shows the relationship between 34 and AC ratio. For each of sample numbers 1 to 10 of the comparative example, the inter-electrode order No. 1-No. It is a figure which shows the relationship between 34 and AC ratio.

Explanation of symbols

  10: power generation element, 11: positive electrode member, 12: negative electrode member, 13: separator member, 20: exterior member, 30: positive electrode terminal, 40: negative electrode terminal, 100: battery.

Claims (1)

In a method for manufacturing a battery, wherein a plurality of positive electrode members made of a positive electrode active material and a current collector and a plurality of negative electrode members made of a negative electrode active material and a current collector are alternately stacked with a separator member interposed therebetween ,
Creating a plurality of positive member mass ranks ranked in order of mass so that each has a predetermined mass range;
Creating a plurality of negative member mass ranks ranked in order of mass so that each has a predetermined mass range;
Measuring the mass of each of the plurality of positive electrode members, and sorting the plurality of positive electrode members into the positive electrode member mass rank of the mass range to which each mass of the measured positive electrode member belongs;
Measuring the mass of each of the plurality of negative electrode members, and sorting the plurality of negative electrode members into the negative electrode member mass rank of the mass range to which each measured mass of the negative electrode member belongs;
A mass rank of the negative electrode member mass rank to which each of the plurality of negative electrode members belongs so that a mass rank of the positive electrode member mass rank to which each of the plurality of positive electrode members belongs is increased along a predetermined stacking direction. A step of alternately laminating the plurality of positive electrode members and negative electrode members with the separator members interposed therebetween so that the height of the battery becomes higher.

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