JP6206237B2 - Manufacturing method of all solid state battery - Google Patents

Description

  The present invention relates to a method for manufacturing an all-solid battery.

  In recent years, a secondary battery has become an indispensable component as a power source for personal computers, video cameras, mobile phones, and the like, or as a power source for automobiles and power storage.

  Among secondary batteries, a lithium ion secondary battery has a feature that it has a higher capacity density than other secondary batteries and can operate at a high voltage. Therefore, it is used in information-related equipment and communication equipment as secondary batteries that are easy to reduce in size and weight. In recent years, high-output and high-capacity lithium-ion secondary batteries for electric vehicles and hybrid vehicles as low-pollution vehicles have been used. Development is underway.

  A lithium ion secondary battery or a lithium secondary battery includes a positive electrode layer and a negative electrode layer, and an electrolyte containing a lithium salt disposed between the positive electrode layer and the negative electrode layer, and the electrolyte is constituted by a non-aqueous liquid or solid. . When a non-aqueous liquid electrolyte is used for the electrolyte, the electrolyte solution penetrates into the positive electrode layer, so that an interface between the positive electrode active material constituting the positive electrode layer and the electrolyte is easily formed, and performance is easily improved. . However, since widely used electrolytes are flammable, it is necessary to install a system for ensuring safety such as attachment of a safety device that suppresses temperature rise at the time of short circuit and prevention of short circuit. In contrast, an all-solid battery in which the liquid electrolyte is changed to a solid electrolyte to make the battery all solid does not use a flammable organic solvent in the battery, so the safety device can be simplified, and manufacturing costs and productivity can be reduced. It is considered excellent and is being developed.

  In such an all-solid battery, a unit battery element having a porous layer disposed between a positive electrode and a negative electrode, at least a part of the outer edge of the unit battery element is an outer edge of the positive electrode and / or the negative electrode A structure in which the porous layer does not protrude from the electrode having the larger outer dimension is proposed (Patent Document 1).

JP 2001-006741 A

  According to Patent Document 1, the outer edge portion of the positive electrode and / or the negative electrode can be used as a positioning portion. However, when any one of the positive electrode and the negative electrode has a small outer dimension, it is difficult to align an electrode having a small outer dimension. When attempting to stack the electrodes so that the displacement of the electrode having a small outer dimension does not occur, there is a problem that the equipment for that is complicated and time is required.

  Therefore, there is a demand for a method for manufacturing an all-solid-state battery that can be stacked more easily and accurately than before.

The present invention provides (A) one or more positive electrode bodies including a positive electrode active material layer and a positive electrode current collector layer,
(B) a step of providing one or more negative electrode bodies including a negative electrode active material layer and a negative electrode current collector layer and having different outer dimensions with respect to the positive electrode body;
(C) At least part of the electrode body having a smaller outer dimension among at least one positive electrode body and one or more negative electrode bodies, the outer dimension of the one or more positive electrode bodies is increased by increasing the outer dimension of the electrode body. A step of covering with a solid electrolyte layer so as to approximate the external dimensions of the negative electrode body,
(D) a step of forming a laminate by alternately laminating one or more positive electrode bodies and one or more negative electrode bodies, at least one of which is covered with a solid electrolyte layer, so that the solid electrolyte layers are disposed therebetween, And (E) one or more positive electrode bodies and one or more negative electrode bodies are aligned on the basis of at least two locations on the outer periphery thereof, and the laminate is pressed to produce an all-solid battery,
Is a method for producing an all-solid battery.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the all-solid-state battery which can align and laminate | stack an electrode body is easier and more accurate than before.

FIG. 1 is a schematic cross-sectional view illustrating a conventional general all-solid battery manufacturing process. FIG. 2 is a schematic cross-sectional view of a conventional general all solid state battery. FIG. 3 is a schematic cross-sectional view of a conventional general all-solid battery manufacturing process. FIG. 4 is a schematic cross-sectional view of a positive electrode body including one positive electrode active material layer and one positive electrode current collector layer. FIG. 5 is a schematic cross-sectional view of a positive electrode body having a total three-layer structure in which one positive electrode current collector layer is sandwiched between two positive electrode active material layers. FIG. 6 is a schematic cross-sectional view of a negative electrode body including one negative electrode active material layer and one negative electrode current collector layer. FIG. 7 is a schematic cross-sectional view of a negative electrode body having a total three-layered structure in which one negative electrode current collector layer is sandwiched between two negative electrode active material layers. FIG. 8 is a schematic top view illustrating the shapes of a positive electrode body and a negative electrode body having different external dimensions. FIG. 9 is a schematic cross-sectional view of a positive electrode body having a smaller outer dimension with both surfaces of the main surface covered with a solid electrolyte layer so that the outer dimension of the positive electrode body is larger. FIG. 10 is a schematic cross-sectional view of a part of the main surface of the positive electrode body having a smaller outer dimension covered with a solid electrolyte layer so that the outer dimension of the positive electrode body is larger. FIG. 11 is a schematic cross-sectional view of a part in which a part of an electrode body having a smaller outer dimension is covered with a solid electrolyte layer so that the outer dimension is larger and a solid electrolyte layer is disposed on the other surface of the electrode body. FIG. 12 is a schematic cross-sectional view of a positive electrode body having a smaller outer dimension and covered with a solid electrolyte layer so that the outer dimension of the positive electrode body is larger. FIG. 13 is a schematic cross-sectional view of an electrode body in which solid electrolyte layers are arranged on both surfaces of the main surface of the electrode body having a larger outer dimension. FIG. 14 is a schematic cross-sectional view of an electrode body in which a solid electrolyte layer is disposed on one side of the main surface of the electrode body having a larger outer dimension. FIG. 15 illustrates an example in which the outer dimensions of the positive electrode body are smaller than the outer dimensions of the negative electrode body, and both surfaces of the main surface of the positive electrode body and the negative electrode body are covered with a solid electrolyte layer so that the outer dimensions are larger. It is a cross-sectional schematic diagram to do. FIG. 16 is a schematic cross-sectional view showing an example of a method of covering both surfaces of the main surface of the electrode body with a solid electrolyte layer so as to form a protruding portion as shown in FIG. FIG. 17 is a schematic cross-sectional view showing an example of a method of covering a part of the main surface of the electrode body with a solid electrolyte layer so as to form a protrusion as shown in FIG. FIG. 18 is a schematic cross-sectional view showing an example of a method of covering both surfaces of the main surface of the electrode body with a solid electrolyte layer so as to form a protruding portion as shown in FIG. FIG. 19 is a schematic cross-sectional view illustrating an example of steps (D) and (E). FIG. 20 is a schematic cross-sectional view illustrating an example of steps (D) and (E). FIG. 21 is a schematic cross-sectional view illustrating an example of steps (D) and (E). FIG. 22 is a top view of a positive electrode body having a positive electrode current collecting tab arranged so as to be in contact with the guide of the alignment jig.

  Conventionally, in an all-solid battery, a structure in which the positive electrode layer and the negative electrode layer have different external dimensions has been proposed. For example, when a carbon-based material is used as the negative electrode active material in a sulfide all-solid battery, In order to suppress the precipitation of lithium, a structure in which the outer dimension of the positive electrode layer is made smaller than the outer dimension of the negative electrode layer has been proposed. Moreover, in order to suppress the short circuit between a positive electrode layer and a negative electrode layer, the structure from which an external dimension differs is proposed.

  As an example of a method for manufacturing an all-solid battery having a configuration in which the outer dimension of the positive electrode layer and the outer dimension of the negative electrode layer are different, the outer dimension of the positive electrode layer 1 is changed to the outer dimension of the negative electrode layer 2 as shown in FIG. It is proposed that the positive electrode layer 1 and the positive electrode current collector 4, and the negative electrode current collector 5, the negative electrode layer 2, and the solid electrolyte layer 3 are laminated. FIG. 1 includes a positive electrode layer 1, a negative electrode layer 2, a solid electrolyte layer 3, a positive electrode current collector 4, and a negative electrode current collector 5, and the external dimensions of the positive electrode layer 1 are smaller than the external dimensions of the negative electrode layer 2. It is a cross-sectional schematic diagram explaining the manufacturing process of a general all-solid-state battery.

  In this case, when the outer peripheral portion is used as an alignment portion, the positive electrode current collector 4 and the positive electrode layer 1 are located at the center of the negative electrode current collector 5, the negative electrode layer 2, and the solid electrolyte layer 3, as shown in FIG. It is not arranged, and a short circuit easily occurs between the positive electrode layer 1 and the negative electrode layer 3. When the positive electrode layer 1 and the positive electrode current collector 4 having small external dimensions are arranged at the center of the negative electrode current collector 5, the negative electrode layer 2, and the solid electrolyte layer 3, the direction is parallel to the laminated surface (in the direction of the arrow). There was a problem that the positional deviation was likely to occur, and the equipment for arranging in the center became complicated and required time.

  Further, as shown in FIG. 1, when a battery having a laminated structure including two or more of the positive electrode layer 1 and the negative electrode layer 2 each having an outer dimension larger than that of the positive electrode layer 1 is manufactured, as shown in FIG. When the positive electrode layer 1 is observed from the direction perpendicular to the laminated surface, the positive electrode layer 1 disposed inside the laminated body is hidden behind the negative electrode layer 2 and cannot be seen. As shown in FIG. 3, when the position of the positive electrode layer 1 is shifted in the direction parallel to the stacking surface, the range in which pressure is applied when restraining the all-solid battery 100 in the direction perpendicular to the stacking surface is limited to the inside of the broken line. As a result, the output of the all-solid-state battery 100 is reduced.

  In order to solve the problem of the all-solid-state battery in which the positive electrode layer and the negative electrode layer have non-identical sizes as described above, the present inventor has intensively studied, and at least of the positive electrode body or the negative electrode body has an electrode body having a smaller outer dimension. At least a part is covered with a solid electrolyte layer so that the outer dimensions of the electrode body are increased and the outer dimensions of the positive electrode body and the negative electrode body are approximated, and at least one of the positive electrode body and the negative electrode body covered with the solid electrolyte layer is Laminate alternately so that the solid electrolyte layers are disposed between, and align at least two of the outer peripheral portions of the positive electrode body and the negative electrode body, at least one of which is covered with the solid electrolyte layer, as a reference A method for producing an all-solid-state battery including pressing was found.

  The present invention includes (A) a step of providing one or more positive electrode bodies including a positive electrode active material layer and a positive electrode current collector layer, (B) a negative electrode active material layer and a negative electrode current collector layer, A step of providing one or more negative electrode bodies having different outer dimensions; (C) at least part of an electrode body having a smaller outer dimension among at least one positive electrode body and one or more negative electrode bodies; A step of covering with a solid electrolyte layer so that the external dimensions of one or more positive electrode bodies and the external dimensions of one or more negative electrode bodies are close to each other, (D) one or more of at least one covered with a solid electrolyte layer A step of alternately laminating a positive electrode body and one or more negative electrode bodies so that a solid electrolyte layer is disposed between them, and (E) one or more positive electrode bodies and one or more negative electrode bodies Align at least two locations on the outer perimeter The laminate was pressed, the step of producing an all-solid battery, including, directed to a method for manufacturing an all-solid battery. According to the present invention, it is possible to obtain an all-solid battery in which a positive electrode body and a negative electrode body are aligned and stacked more easily and accurately than before.

  Hereinafter, a method according to the present invention will be described with reference to the drawings.

  In FIG. 4, the cross-sectional schematic diagram showing an example of the process (A) included in the method which concerns on this invention is shown. Step (A) includes providing one or more positive electrode bodies 10 including the positive electrode active material layer 11 and the positive electrode current collector layer 12.

  The positive electrode body 10 is a laminate that includes one or more positive electrode active material layers 11 and positive electrode current collector layers 12 and has an outer dimension 13. FIG. 4 is a schematic cross-sectional view of a positive electrode body 10 including one positive electrode active material layer 11 and one positive electrode current collector layer 12, and FIG. 5 illustrates one layer between two positive electrode active material layers 11. 1 is a schematic cross-sectional view of a positive electrode body 10 having a total of three layers sandwiching a positive electrode current collector layer 12 therebetween.

  The positive electrode body 10 preferably has a symmetrical structure as shown in FIG. 5 and has positive electrode active material layers 11 having substantially the same thickness on both surfaces of the positive electrode current collector layer 12. As long as the positive electrode active material layers 11 formed on both surfaces of the positive electrode current collector layer 12 have the same thickness, the number of layers constituting the positive electrode active material layer 11 may be different. When the positive electrode body 10 has a symmetric structure, it becomes easy to suppress the curvature of the positive electrode body 10. When the positive electrode body 10 has an asymmetric structure as shown in FIG. 4, it is preferable to use a current collector having high rigidity such as a metal plate in order to suppress the warpage of the positive electrode body 10.

  In FIG. 6, the cross-sectional schematic diagram showing an example of the process (B) included in the method which concerns on this invention is shown. The step (B) includes providing the one or more negative electrode bodies 20 including the negative electrode active material layer 21 and the negative electrode current collector layer 22 and having different outer dimensions with respect to the positive electrode body 10.

  The negative electrode body 20 is a laminate including one or more negative electrode active material layers 21 and negative electrode current collector layers 22 and having an outer dimension 23. FIG. 6 is a schematic cross-sectional view of the negative electrode body 20 including one negative electrode active material layer 21 and one negative electrode current collector layer 22, and FIG. 7 illustrates one layer between the two negative electrode active material layers 21. 1 is a schematic cross-sectional view of a negative electrode body 20 having a laminated structure of a total of three layers with a negative electrode current collector layer 22 interposed therebetween.

  The negative electrode body 20 preferably has a symmetric structure as shown in FIG. 7 and has negative electrode active material layers 21 having substantially the same thickness on both surfaces of the negative electrode current collector layer 22. As long as the negative electrode active material layers 21 formed on both surfaces of the negative electrode current collector layer 22 have the same thickness, the number of layers constituting the negative electrode active material layer 21 may be different. When the negative electrode body 20 has a symmetric structure, it becomes easy to suppress the curvature of the negative electrode body 20. When the negative electrode body 20 has an asymmetric structure as shown in FIG. 6, it is preferable to use a current collector having high rigidity such as a metal plate in order to suppress warping of the negative electrode body 20.

  The positive electrode active material layers 11 formed on both surfaces of the positive electrode current collector layer 12 have the same thickness, and the negative electrode active material layers 21 formed on both surfaces of the negative electrode current collector layer 22 have the same thickness. Is preferably within 10%, more preferably within 5%, still more preferably within 1%, and even more preferably, with respect to the difference in thickness of the electrode active material layers formed on both surfaces, based on the smaller thickness. Means substantially 0%.

  4 to 7 exemplify a case where the outer dimension 13 of the positive electrode body 10 is smaller than the outer dimension 23 of the negative electrode body 20, and the outer dimension 13 of the positive electrode body 10 is larger than the outer dimension 23 of the negative electrode body 20. May be.

  The positive electrode body 10 and the negative electrode body 20 are preferably polygonal or circular similar shapes. When the positive electrode body 10 and the negative electrode body 20 have a polygonal shape, the positive electrode body 10 and the negative electrode body 20 are more preferably a substantially regular polygon shape or a quadrangular shape with four angles being substantially 90 °, The shape is preferably square. When the positive electrode body 10 and the negative electrode body 20 are circular, the positive electrode body 10 and the negative electrode body 20 are more preferably substantially circular.

  The external dimensions 13 of the positive electrode body 10 and the external dimensions 23 of the negative electrode body 20 are, for example, such that the external dimensions of the positive electrode body 10 are 50 to 99% or 76 to 97% of the external dimensions of the negative electrode body 20. Can have.

  The positive electrode active material layer 11 included in the positive electrode body provided in the step (A) and the negative electrode active material layer 21 provided in the step (B) can each be formed and prepared on a substrate.

  The formation of the positive electrode active material layer 11 and the negative electrode active material layer 21 on the substrate is performed by a slurry coating process, a blast method, an aerosol deposition method, a cold spray method, a sputtering method, a vapor phase growth method, a thermal spray method, or the like. The positive electrode active material layer 11 and the negative electrode active material layer 21 can be obtained by a process in which the slurry coating process is simple and is preferably used.

  The substrate is not particularly limited as long as the positive electrode active material layer 11 and the negative electrode active material layer 21 can be formed thereon, and is used as the positive electrode current collector 12 or the negative electrode current collector 22. A metal current collector to be obtained, a base material having a film-like flexibility, a hard base material, and the like can be used. For example, a metal foil, a metal plate, a polyethylene terephthalate (PET) film, a Teflon (registered trademark) base material, etc. Can be used.

  The positive electrode active material layer 11 is preferably formed using the positive electrode current collector 12 as a base material, and the negative electrode active material layer 21 is preferably formed using the negative electrode current collector 22 as a base material. In this case, an electrode body can be obtained by forming electrode active material layers on both sides of the current collector. Moreover, after forming an electrode active material layer on both surfaces of an electrical power collector, you may press, forming an electrode active material layer on both surfaces of an electrical power collector, and obtaining an electrode body, process (C) Thus, pressing may be performed after combining the electrode body and the solid electrolyte layer. When forming an electrode active material layer on a substrate other than the current collector, the electrode active material layer is peeled off from the substrate and placed on the current collector, or the electrode active material layer on the substrate is collected The electrode body can be obtained by transferring onto the body.

  The material of the positive electrode current collector 12 is not particularly limited as long as it has conductivity and functions as a positive electrode current collector. For example, SUS, aluminum, copper, nickel, iron, titanium, and Carbon etc. can be mentioned, SUS and aluminum are preferable. Furthermore, examples of the shape of the positive electrode current collector 12 include a foil shape, a plate shape, and a mesh shape. Of these, a foil shape is preferable.

  The material of the negative electrode current collector 22 is not particularly limited as long as it has conductivity and functions as a negative electrode current collector. Examples thereof include SUS, copper, nickel, and carbon. SUS and copper are preferred. Furthermore, examples of the shape of the negative electrode current collector 22 include a foil shape, a plate shape, and a mesh shape. Among these, a foil shape is preferable.

  A positive electrode tab and a negative electrode tab can be connected to the positive electrode current collector layer 12 and the negative electrode current collector layer 22, respectively.

  The thickness of the positive electrode current collector 12 and the negative electrode current collector 22 is not particularly limited, and for example, a metal foil having a thickness of about 10 to 500 μm can be used.

  Examples of the slurry coating process include a dam type slurry coater, a doctor blade method, a gravure transfer method, and a reverse roll coater. Through such a slurry coating process, the positive electrode active material layer 11 and the negative electrode active material layer 21 can be obtained by coating and drying the slurry containing the positive electrode active material and the slurry containing the negative electrode active material on the substrate. .

  The positive electrode active material layer 11 includes a positive electrode active material, and may include a solid electrolyte, a conductive additive, and a binder as desired. The negative electrode active material layer 21 also includes a negative electrode active material, and may optionally include a solid electrolyte, a conductive additive, and a binder.

  Therefore, the slurry containing the positive electrode active material contains the positive electrode active material and, if desired, is prepared containing a solid electrolyte, a conductive additive, and a binder. The slurry containing the negative electrode active material contains the negative electrode active material, and optionally , A solid electrolyte, a conductive aid, and a binder.

  The solvent used for preparing the slurry containing the positive electrode active material and the slurry containing the negative electrode active material is not particularly limited as long as it does not adversely affect the performance of the positive electrode active material and the negative electrode active material. Examples thereof include heptane, toluene, hexane, and the like. Preferably, a hydrocarbon-based organic solvent that has been dehydrated to reduce the water content is used.

In the present invention, as the active material contained in the positive electrode active material layer 11 and the negative electrode active material layer 21, a material that can be used as an electrode active material of an all-solid battery can be used. Examples of the active material include lithium cobaltate (LiCoO ₂ ), lithium nickelate (LiNiO ₂ ), lithium manganate (LiMn ₂ O ₄ ), LiCo _1/3 Ni _1/3 Mn _1/3 O ₂ , Li _{1 + x Mn 2-xy M y} O 4 (M is, Al, Mg, Co, Fe, Ni, and one or more metal elements selected from Zn) different element substituted Li-Mn spinel composition represented by, Transition metal oxidation such as lithium titanate (Li _x TiO _y ), lithium metal phosphate (LiMPO ₄ , M is Fe, Mn, Co, or Ni), vanadium oxide (V ₂ O ₅ ), and molybdenum oxide (MoO ₃ ) things, titanium sulfide (TiS _2), carbon materials such as graphite and hard carbon, lithium-cobalt nitride (LiCoN), lithium silicon oxide _{(Li x Si y O z)} , lithium metal (L ), Lithium alloy (LiM, M is, Sn, Si, Al, Ge, Sb, or P), lithium storage intermetallic compound (Mg _x M or NySb, M is Sn, Ge or Sb, N is an In,,, Cu, or Mn) and the like, and derivatives thereof.

  In the present invention, there is no clear distinction between the positive electrode active material and the negative electrode active material, and the two types of charge / discharge potentials are compared. Can be used as a negative electrode to form a battery having an arbitrary voltage.

In the present invention, as a solid electrolyte material that can be included in the positive electrode active material layer 11 and the negative electrode active material layer 21, a material that can be used as a solid electrolyte of an all-solid battery can be used. For example, for _{example, Li 2 S-SiS 2,} LiI-Li 2 S-SiS 2, LiI-Li 2 S-P 2 S 5, LiI-Li 2 S-B 2 S 3, Li 3 PO 4 -Li 2 S _{-Si 2 S, Li 3 PO 4} -Li 2 S-SiS 2, LiPO 4 -Li 2 S-SiS, LiI-Li 2 S-P 2 O 5, LiI-Li 3 PO 4 -P 2 S 5, or Sulfide-based solid electrolytes such as Li ₂ S—P ₂ S ₅ , Li ₂ O—B ₂ O ₃ —P ₂ O ₅ , Li ₂ O—SiO ₂ , Li ₂ O—B ₂ O ₃ , or Li ₂ O Oxide-based amorphous solid electrolyte such as -B ₂ O ₃ -ZnO, Li _1.3 Al _0.3 Ti _0.7 (PO ₄ ) ₃ , Li _{1 + x + y} A _x Ti _2-x Si _y P _3-y O ₁₂ (A is Al or Ga, 0 ≦ x ≦ 0.4, 0 <y ≦ 0.6), [(B _1/2 Li _1/2 ) _1−z C _z ] TiO ₃ (B is La, Pr, Nd, or Sm, Is Sr or Ba, 0 ≦ z ≦ 0.5) , Li 5 La 3 Ta 2 O 12, Li 7 La 3 Zr 2 O 12, Li 6 BaLa 2 Ta 2 O 12 or _{Li 3.6 Si 0.6 P 0.4 O 4} , Crystalline oxide such as Li ₃ PO _{(4-3 / 2w)} N _w (w <1), or LiI, LiI—Al ₂ O ₃ , Li ₃ N, or Li ₃ N -LiI-LiOH or the like can be used. A sulfide-based solid electrolyte is preferably used in that it has excellent lithium ion conductivity. Further, as the solid electrolyte of the present invention, a semi-solid polymer electrolyte such as polyethylene oxide, polypropylene oxide, polyvinylidene fluoride, or polyacrylonitrile containing a lithium salt can also be used. Further, an amorphous sulfide-based solid electrolyte that has been heat-treated at, for example, about 140 to 220 ° C. to form a glass ceramic can be used as the solid electrolyte.

  When the positive electrode active material layer 11 and the negative electrode active material layer 21 contain a solid electrolyte, the mixing ratio of the electrode active material and the solid electrolyte is not particularly limited. For example, the volume ratio of the electrode active material: solid electrolyte is 20: It can be 80-90: 10 or 40: 60-70: 30.

When the positive electrode active material layer 11 contains a sulfide-based solid electrolyte, the high resistance layer is hardly formed at the interface between the positive electrode active material and the sulfide-based solid electrolyte, so that an increase in battery resistance can be easily prevented. From this viewpoint, the positive electrode active material is preferably coated with an ion conductive oxide. As the lithium ion conductive oxide covering the positive electrode active material, for example, the general formula LixAOy (A is B, C, Al, Si, P, S, Ti, Zr, Nb, Mo, Ta or W, x and y are positive numbers)). Specifically, Li ₃ BO ₃ , Li _B O ₂ , Li ₂ CO ₃ , LiAlO ₂ , Li ₄ SiO ₄ , Li ₂ SiO ₃ , Li ₃ PO ₄ , Li ₂ SO ₄ , Li ₂ TiO ₃ , Li ₄ Examples thereof include Ti ₅ O ₁₂ , Li ₂ Ti ₂ O ₅ , Li ₂ ZrO ₃ , LiNbO ₃ , Li ₂ MoO ₄ , Li ₂ WO _{4 and the} like. The lithium ion conductive oxide may be a complex oxide.

As the composite oxide covering the positive electrode active material, any combination of the above lithium ion conductive oxides can be employed. For example, Li ₄ SiO ₄ —Li ₃ BO ₃ , Li ₄ SiO ₄ —Li ₃ PO ₄ etc. can be mentioned.

  Further, when the surface of the positive electrode active material is coated with an ion conductive oxide, the ion conductive oxide only needs to cover at least part of the positive electrode active material, and covers the entire surface of the positive electrode active material. Also good. In addition, the thickness of the ion conductive oxide covering the positive electrode active material is, for example, preferably from 0.1 nm to 100 nm, and more preferably from 1 nm to 20 nm. The thickness of the ion conductive oxide can be measured using, for example, a transmission electron microscope (TEM).

  The material of the binder that can be included in the positive electrode active material layer and the negative electrode active material layer is not particularly limited, and is polytetrafluoroethylene, polybutadiene rubber, hydrogenated butylene rubber, styrene butadiene rubber, polysulfide rubber, polyvinyl fluoride, polyfluoride. Vinylidene or the like can be used.

  Each of the positive electrode active material layer and the negative electrode active material layer may include conductive aid particles as desired. The conductive aid particles are not particularly limited, and graphite, carbon black and the like can be used.

  The thickness of the positive electrode active material layer and the negative electrode active material layer before pressing is preferably 1.5 to 3000 μm, more preferably 7.5 to 300 μm, respectively. When the thickness of the positive electrode active material layer and the negative electrode active material layer before pressing is in the above range, the thickness of the positive electrode active material layer and the negative electrode active material layer after pressing is preferably 1 μm to 1 mm, more preferably 5 μm, respectively. It can be set to ˜100 μm.

Electrode body used in the process according to the present invention, depending on the characteristics of the battery such as requiring, for example, external dimensions of the arbitrary area such as 1～3000Cm ² or 10～1000Cm ^2,, and 20~2500μm or, It can have any thickness such as 50-300 μm.

  FIG. 9 is a schematic diagram showing an example of the step (C) included in the method according to the present invention. In step (C), at least a part of an electrode body having a smaller outer dimension is selected from at least one positive electrode body and one or more negative electrode bodies, and the outer dimension of the electrode body is increased by increasing the outer dimension of the electrode body. It includes covering with the solid electrolyte layer 30 so that a dimension and the external dimension of one or more negative electrode bodies may be approximated.

  In the step (C), at least a part of at least a part of the electrode body having a smaller outer dimension among the one or more positive electrode bodies and the one or more negative electrode bodies, When the positive electrode body and the negative electrode body are laminated in the step (D) and the alignment is performed in the step (E) by covering with a solid electrolyte layer so that the dimensions and the outer dimensions of the one or more negative electrode bodies are close to each other, The positive electrode body 10 and the negative electrode body 20 can be simply and accurately aligned to stack the electrode bodies.

  In the present application, “the outer dimension is smaller” means that, for example, when the disc-shaped positive electrode body 10 and the negative electrode body 20 are arranged so as to contact each other, the outer dimension of one electrode body is the other electrode as shown in FIG. The size is smaller than the outer dimension of the body, and the entire outer circumference of one electrode body falls within the plane of the other electrode body. “The outer dimension is larger” means that the outer dimension of one electrode body is larger than the outer dimension of the other electrode body, and the outer circumference of one electrode body does not entirely fall within the plane of the other electrode body. Say. The external dimensions are projected dimensions as shown in FIG.

  FIG. 9 is a schematic cross-sectional view of the main surface 15 of the positive electrode body 10 having a smaller outer dimension covered with the solid electrolyte layer 30 so as to increase the outer dimension 13, and FIG. 2 is a schematic cross-sectional view of a part of a main surface 15 of a small positive electrode body 10 covered with a solid electrolyte layer 30 so as to increase an outer dimension 13; FIG. If the solid electrolyte layer 30 is in close contact with both surfaces of the main surface of the electrode body (the surface in contact with the other electrode body having different outer dimensions when laminated), the solid electrolyte layer 30 is not in close contact with the side surface portion 33 of the electrode body. Alternatively, a space may be formed in the side surface portion 33 between the electrode body and the solid electrolyte layer. When at least a part of the electrode body is covered with the solid electrolyte layer 30, a part of the current collector or a current collecting tab connected to the current collector can be covered so as to be drawn out of the solid electrolyte layer 30. In order to suppress warping of the electrode body, it is preferable to form the solid electrolyte layer symmetrically as shown in FIG.

  In step (C), at least the outer dimensions of the positive electrode body and the negative electrode body are made closer to each other in order to increase the outer dimension of the electrode body having a smaller outer dimension and bring the outer dimension of the positive electrode body closer to the outer dimension of the negative electrode body, as shown in FIGS. At least a part of the electrode body having a smaller size can be covered with the solid electrolyte layer 30 so that the protruding portions 32 are formed at least at two places on the side surface portion 33 of the electrode body. The protrusion 32 can be formed at the end (outer periphery) of the solid electrolyte layer 30 disposed so as to cover the electrode body.

  As shown in FIG. 11, a solid electrolyte layer 31 may be further arranged on the electrode body partially covered with the solid electrolyte layer 30 shown in FIG. 10 to cover the entire surface of the electrode body. The outer dimension of the solid electrolyte layer 31 is the same as or larger than that of the electrode active material layer 11 and can be the same as or smaller than the outer dimension 13.

  Further, as shown in FIG. 12, the solid electrolyte layer 30 is folded in order to at least increase the outer dimension of the electrode body having a smaller outer dimension and bring the outer dimension of the positive electrode body closer to the outer dimension of the negative electrode body. In addition, at least a part of the electrode body having a smaller outer dimension may be covered so that the protruding portion 32 is formed in at least one position of the side surface portion 33 of the electrode body. In this case, a folded portion 34 is formed on the side surface portion 33 of the solid electrolyte layer 30. Similarly, when covering at least the entire surface of the electrode body having a smaller outer dimension with the solid electrolyte layer 30, the end of the solid electrolyte layer 30 other than the folded portion 34 (the outer peripheral portion of the solid electrolyte layer 30, and the electrode body 10 The protrusions 32 are formed on the left side of FIG. Since the folded portion 34 also has a predetermined thickness, the outer dimensions of the electrode body can be increased not only by the protruding portion 32 but also by the thickness of the folded portion 34. For example, when the protruding portion 32 is formed at the end (outer peripheral portion) of the solid electrolyte layer 30 and on the near side in the direction perpendicular to the paper surface, the alignment can be performed with reference to the two portions of the protruding portion 32 and the folded portion 34. it can. In order to make it easier to align the electrode body having a smaller outer dimension with the central portion of the electrode body having a larger outer dimension, the protrusions 32 are formed at least at two positions on the side surface portion 33 of the electrode body. Is preferred. Thus, the external dimension of the electrode body having a smaller external dimension can be increased by an arbitrary method using the solid electrolyte layer.

  In the step (C), the solid electrolyte layer may or may not be disposed on the electrode body having a larger outer dimension among the positive electrode body 10 and the negative electrode body 20. When the solid electrolyte layer is arranged on the electrode body having a larger outer dimension, the solid electrolyte layer is formed on both sides or one side of the electrode body so as not to change the outer dimension of the electrode body having a larger outer dimension as shown in FIGS. 31 may be disposed, or, similarly to those shown in FIGS. 9 to 12, may be covered with a solid electrolyte layer so as to increase the outer dimension of the electrode body having a larger outer dimension.

  In the step (C), when the solid electrolyte layer is not disposed on the electrode body having a larger outer dimension, in order to interpose the solid electrolyte layer between the positive electrode body 10 and the negative electrode body 20, FIGS. As shown, it is preferable to cover both surfaces of the main surface of the electrode body having a smaller outer dimension with the solid electrolyte layer 30 so as to increase the outer dimension. In the step (C), when forming an electrode body with a smaller outer dimension partially covered with the solid electrolyte layer 30 as shown in FIG. 10 (one surface in contact with the electrode body with a larger outer dimension when stacked) When the positive electrode body 10 and the negative electrode body 20 are laminated in the step (D), a separate solid electrolyte layer is prepared and the positive electrode body 10 A solid electrolyte layer can be disposed between the negative electrode body 20.

  In the step (C), when the solid electrolyte layer is disposed on the entire surface of both surfaces of the electrode body having a larger outer dimension in the manner shown in FIGS. 9 and 11 to 13, the outer shape is illustrated as illustrated in FIGS. 9 to 13. What is necessary is just to cover a part of electrode body with a smaller dimension with the solid electrolyte layer 30 so that an external dimension may become large.

  Further, when the strength of the solid electrolyte layer 30 is sufficiently high, as shown in FIG. 10, a part of the electrode body having a smaller outer dimension may be covered with the solid electrolyte layer 30 so that the outer dimension becomes larger. When the strength of the solid electrolyte layer 30 is not so high, as shown in FIGS. 9, 11, and 12, the outer dimensions are smaller so that the protrusions 32 are formed at the ends of the two solid electrolyte layers 30. It is preferable to cover both surfaces of the electrode body with the solid electrolyte layer 30 so that the outer dimensions are large. By forming the protrusion 32 at the end of the two solid electrolyte layers 30, the strength of the protrusion 32 can be further increased. More preferably, the protrusion 32 is formed by pressing the two solid electrolyte layers 30. For example, the structure shown in FIGS. 9 and 12 is preferable.

  In the step (C), as long as the outer dimensions of the one or more positive electrode bodies and the one or more negative electrode bodies are approximated, at least the electrode body having a larger outer dimension as in the embodiments shown in FIGS. A part may be covered with the solid electrolyte layer 30. Further, as shown in FIGS. 13 and 14, the solid electrolyte layer 31 may be disposed on one side or both sides of the main surface 25 of the electrode body having a larger outer dimension. FIG. 13 is a schematic cross-sectional view of an electrode body in which solid electrolyte layers 31 are arranged on both surfaces of the main surface 25 of the electrode body having a larger outer dimension, and FIG. 14 shows the main surface 25 of the electrode body having a larger outer dimension. It is a cross-sectional schematic diagram of the electrode body which has arrange | positioned the solid electrolyte layer 31 on the single side | surface.

  In the step (C), for example, as shown in FIG. 15, both surfaces of the main surfaces of both the positive electrode body 10 and the negative electrode body 20 may be covered with a solid electrolyte layer 30 so that the respective outer dimensions are increased. . FIG. 15 shows a case where the external dimensions of the positive electrode body 10 are smaller than the external dimensions of the negative electrode body 20, and the solid electrolyte is formed so that the external dimensions of both surfaces of the positive electrode body 10 and the negative electrode body 20 are large. 3 is a schematic cross-sectional view illustrating an embodiment covered with a layer 30. FIG.

  In step (C), at least a part of the electrode body having a smaller outer dimension is covered with a solid electrolyte layer, so that the difference between the outer dimension 13 of the positive electrode body 10 and the outer dimension 23 of the negative electrode body 20 is further increased. Preferably, within 20%, more preferably within 10%, even more preferably within 5%, even more preferably within 1%, even more preferably substantially 0%, based on the outer dimensions of the large electrode body. Can do. By reducing the external dimension difference between the positive electrode body 10 and the negative electrode body 20 within the above range, the positional deviation between the positive electrode body 10 and the negative electrode body 20 can be further reduced.

  9 to 15, of the positive electrode body 10 and the negative electrode body 20, at least a part of the positive electrode body 10 having a smaller outer dimension, the outer dimension of the positive electrode body 10 is increased by increasing the outer dimension of the positive electrode body 10. The case where it covers with the solid electrolyte layer 30 is illustrated so that 20 external dimensions may approach. When the outer dimension of the negative electrode body 20 is smaller than the outer dimension of the positive electrode body 10, at least a part of the negative electrode body 20 having a smaller outer dimension is covered with the solid electrolyte layer 30.

  The solid electrolyte layer used in the step (C) can be prepared by forming on a substrate. The formation of the solid electrolyte layer on the base material can be performed by the same method as that for forming the positive electrode active material layer and the negative electrode active material layer, and the solid electrolyte layer can be obtained by a process with a simple slurry coating process. Can be used preferably. In addition, as described below, when the solid electrolyte layer is formed including the reinforcing material used as the skeleton material, the reinforcing material can be impregnated with the slurry containing the solid electrolyte and dried to obtain the solid electrolyte layer.

  The substrate is not particularly limited as long as the solid electrolyte layer can be formed thereon, and the same material as that used for forming the positive electrode active material layer and the negative electrode active material layer is used. For example, a base material such as an Al foil can be used. In addition, as shown in FIGS. 13 and 14, when the solid electrolyte layer is arranged on both sides or one side of the main surface of the electrode body so as not to change the outer dimensions of the electrode body, the solid electrolyte layer is directly arranged on the electrode body. May be.

  Examples of the slurry coating process include a dam type slurry coater, a doctor blade method, a gravure transfer method, and a reverse roll coater. By such a slurry coating process, a slurry containing a solid electrolyte can be coated on a substrate and dried to obtain a solid electrolyte layer.

  The solid electrolyte layer includes a solid electrolyte, and may include a reinforcing material (skeleton material) and a binder as desired. The solid electrolyte layer preferably includes a reinforcing material. By forming the solid electrolyte layer including the reinforcing material, the strength of the solid electrolyte layer can be increased and alignment can be performed more easily. Thus, a slurry containing a solid electrolyte can be prepared containing a solid electrolyte and, optionally, a reinforcing material and a binder.

  As the solid electrolyte material contained in the solid electrolyte layer, the materials mentioned as the solid electrolyte that can be contained in the positive electrode active material layer 11 and the negative electrode active material layer 21 can be used. Preferably, the solid electrolyte contained in the solid electrolyte layer The material and the solid electrolyte material that can be included in the positive electrode active material layer 11 and the negative electrode active material layer 21 are the same.

  Examples of the binder material that can be included in the solid electrolyte layer include the same materials as the positive electrode active material layer and the negative electrode active material layer, and are not particularly limited.

  The reinforcing material that can be included in the solid electrolyte layer is not particularly limited as long as it can improve the strength of the solid electrolyte layer as a skeletal material, and includes a solid electrolyte and has lithium ion conductivity and electrical insulation. Not. Examples of the reinforcing material include a film or mesh material having pores that can be filled with a solid electrolyte, and examples thereof include a polyethylene terephthalate (PET) film, a polypropylene (PP) film, and a polypropylene (PP) mesh material. .

  For example, a solid electrolyte layer can be obtained by impregnating a slurry containing a solid electrolyte into a polypropylene (PP) mesh material having a porosity of 30 to 95 volume percent and a thickness of 5 to 100 μm and drying. When the reinforcing material is impregnated with the slurry containing the solid electrolyte and dried, the slurry may be impregnated and dried so that the solid electrolyte layer is formed with the same thickness as the reinforcing material, and the solid electrolyte layer is reinforced in the thickness direction. The slurry may be impregnated and dried so that the material is placed.

  The solvent used for the preparation of the slurry containing the solid electrolyte is not particularly limited as long as it does not adversely affect the performance of the solid electrolyte, and examples thereof include hydrocarbon-based organic solvents such as heptane, toluene, and hexane, preferably dehydration. Hydrocarbon organic solvents that have been treated to reduce the water content are used.

  1-300 micrometers is preferable and, as for the thickness of the solid electrolyte layer before a press, 10-30 micrometers is more preferable. When the thickness of the solid electrolyte layer before pressing is in the above range, the thickness of the solid electrolyte layer after pressing can be preferably 1 μm to 150 μm, more preferably 5 to 15 μm, and penetrate the solid electrolyte layer. A short circuit between the positive electrode layer and the negative electrode layer can be prevented.

  As a method of covering both surfaces of the electrode body with the solid electrolyte layer 30 so as to form the protrusions 32 as shown in FIG. 9, as shown in FIG. 16, the solid electrolyte layer 30 having a larger outer dimension than the electrode body is used as the electrode. After placing on the both sides of the body and laminating and fixing the electrode body so as to be sandwiched between the solid electrolyte membranes 30 and putting it in a packaging material such as a laminate, it is evacuated and then cold isostatic press (CIP) etc. There is a method of pressing with an isotropic pressure press. The solid electrolyte membrane 30 disposed on both surfaces of the electrode body may be disposed together with a flexible substrate, and the substrate may be peeled off after pressing.

  The outer dimensions of the solid electrolyte layer used to cover the electrode body with the smaller outer dimension can be selected according to the desired outer dimension 13 and should have the same outer dimension as the electrode body with the larger outer dimension. preferable. When an electrode body having a larger outer dimension is covered with a solid electrolyte layer so that the outer dimension is larger, the outer dimension of the solid electrolyte layer used to cover the electrode body having a smaller outer dimension is the electrode body having a larger outer dimension. It is preferable to have the same outer dimensions as the solid electrolyte layer used for covering.

  As described above, since the thickness of the electrode active material layer after pressing is, for example, about 1 mm or less and the thickness of the current collector is, for example, about 500 μm or less, the solid electrolyte layer after being pressed by an isotropic pressure press The outer dimension does not greatly decrease with respect to the outer dimension of the solid electrolyte layer before pressing, and is substantially the same as the outer dimension of the solid electrolyte layer before pressing. That is, for example, it is not necessary to consider the reduction in the external dimension of the solid electrolyte layer 30 due to the folded portion of the solid electrolyte layer 30 disposed on the side surface portion 33 of the electrode body illustrated in FIG.

  Accordingly, the outer dimensions of the solid electrolyte layer used to cover the electrode body having a smaller outer dimension are the same as those of the electrode body having a larger outer dimension, or the electrode body having a larger outer dimension has a larger outer dimension. In the case of covering with a solid electrolyte layer, it is preferable to have the same outer dimensions as the solid electrolyte layer used for covering an electrode body having a larger outer dimension. FIG. 16 is a schematic diagram in the case where a solid electrolyte layer having an outer dimension larger than that of the positive electrode active material layer 11 is disposed so as to form the protruding portion 32, but the thickness of each layer is greatly illustrated. Therefore, the aspect ratio is different from the actual one.

  Specifically, the outer dimension of the solid electrolyte layer used to cover the electrode body having a smaller outer dimension is preferably 1 to 20 mm larger (0.5 to 10 mm larger on one side) than the outer dimension of the electrode body. More preferably, it is 1 to 4 mm larger (0.5 to 2 mm larger on one side).

  As a method of covering a part of the electrode body with the solid electrolyte layer 30 so as to form the protruding portion 32 as shown in FIG. 10, as shown in FIG. 17, the electrode body and the outer shape larger than the electrode body are formed on the rigid substrate 50. A method in which a solid electrolyte layer 30 having dimensions is arranged and fixed is put in a packaging material such as a laminate and evacuated, and then pressed by an isostatic press similar to the above.

  As a method of covering both surfaces of the electrode body with the solid electrolyte layer 30 so as to form the protruding portion 32 and the folded portion 34 as shown in FIG. 12, the solid electrolyte layer 30 is folded to cover the electrode body as shown in FIG. After placing and fixing in this way into a packaging material such as a laminate and vacuuming, there is a method of pressing with an isostatic press similar to the above.

  The pressing pressure and holding time of the hydrostatic isostatic press (CIP) may be any pressure that allows the solid electrolyte layer to adhere to the main surface of the electrode body, and preferably the electrode active material layer contained in the electrode body can also be densified. The pressure and holding time can be set, the pressing pressure can be preferably 50 to 1000 MPa, more preferably 80 to 600 MPa, and the pressing pressure holding time is preferably 10 seconds to 5 minutes, more preferably 30 seconds to 2 minutes.

  The solid electrolyte layer 30 can cover the electrode body by pulling out a part of the current collector or an electrode tab connected to the current collector. A part of the current collector or a part from which the electrode tab connected to the current collector is drawn out from the solid electrolyte layer 30 can be sealed by ultrasonic welding.

  In the step (D) included in the method according to the present invention, one or more positive electrode bodies and one or more negative electrode bodies, at least one of which is covered with a solid electrolyte layer, are alternately arranged so that the solid electrolyte layers are disposed therebetween. Laminating to form a laminate.

  In the step (E) included in the method according to the present invention, one or more positive electrode bodies and one or more negative electrode bodies are aligned on the basis of at least two locations of the outer peripheral portions, and the laminate is pressed, Including making an all-solid battery.

  In FIG. 19, the cross-sectional schematic diagram showing an example of process (D) and (E) is shown. FIG. 19 shows that in steps (D) and (E), when the external dimensions of the positive electrode body are smaller than the external dimensions of the negative electrode body, both surfaces of the main surface are covered with the solid electrolyte layer 30 so as to form the protrusions 32. The three positive electrode bodies 10 and the three negative electrode bodies 20 having the solid electrolyte layers 31 disposed on both sides of the main surface are alternately laminated so that the solid electrolyte layers are disposed therebetween to form a laminate. FIG. 3 is a schematic cross-sectional view illustrating an embodiment in which three positive electrode bodies 10 and three negative electrode bodies 20 are aligned with respect to at least two locations on the outer peripheral portions thereof and a laminate is pressed. For example, alignment can be performed using either one of the references indicated by a broken line in FIG. 19 and a reference (not shown) in the front or back direction perpendicular to the paper surface.

  In FIG. 20, in steps (D) and (E), when the outer dimensions of the positive electrode body are smaller than the outer dimensions of the negative electrode body, both surfaces of the main surface are covered with the solid electrolyte layer 30 so as to form the protrusions 32. The three positive electrode bodies 10 and the three negative electrode bodies 20 that do not include the solid electrolyte layer are alternately stacked so that the solid electrolyte layers are disposed between the three positive electrode bodies 10 and the three positive electrode bodies 10 and The cross-sectional schematic diagram which illustrates the embodiment which aligns the three negative electrode bodies 20 on the basis of at least two places of each outer peripheral part, and presses a laminated body is shown. For example, alignment can be performed using either one of the references indicated by a broken line in FIG. 20 and a reference (not shown) in the front or back direction perpendicular to the paper surface.

  In FIG. 21, in steps (D) and (E), both sides of the main surface are covered with the solid electrolyte layer 30 so as to form the protrusions 32 when the external dimensions of the positive electrode body are smaller than the external dimensions of the negative electrode body. The three positive electrode bodies 10 and the three negative electrode bodies 20 covered on both surfaces of the main surface with the solid electrolyte layer 30 so as to form the protrusions 32 are alternately stacked so that the solid electrolyte layers are disposed therebetween. The cross-sectional schematic diagram illustrating an embodiment in which the laminated body is formed, the three positive electrode bodies 10 and the three negative electrode bodies 20 are aligned with reference to at least two locations of the outer peripheral portions thereof, and the laminated body is pressed. Indicates. For example, alignment can be performed using either one of the references indicated by a broken line in FIG. 21 and a reference (not shown) in the front or back direction perpendicular to the paper surface.

  In the method according to the present invention, the number of stacks of the positive electrode body 10 and the negative electrode body 20 is 1 or more, and each of the positive electrode body 10 and the negative electrode body 20 is preferably 2 or more, more preferably 5 or more, and still more preferably 10 As described above, 50 or more layers can be stacked. The upper limit of the number of stacked positive electrode bodies 10 and negative electrode bodies 20 is not particularly limited, but may be 500 or less, for example.

  In the step (D), the positive electrode bodies 10 and the negative electrode bodies 20 are alternately laminated so that the solid electrolyte layers are disposed therebetween. Therefore, for example, when using an electrode body in which a part of the main surface of the electrode body as shown in FIG. 10 is exposed, both electrodes of the main surface as shown in FIG. 13 are used as the other electrode body. The electrode body in which the solid electrolyte layer is disposed can be used, and the electrode body in which the solid electrolyte layer is disposed on one side as shown in FIG. What is necessary is just to laminate | stack alternately so that a solid electrolyte layer may be arrange | positioned in between. Alternatively, a separate solid electrolyte layer may be prepared, and the positive electrode body 10 and the negative electrode body 20 may be alternately stacked so that the solid electrolyte layer is disposed therebetween.

  When a laminated body as illustrated in FIGS. 19 to 21 is manufactured, each layer of the electrode body 10 may have the same structure or a different structure. Similarly, each layer of the electrode body 20 may have the same structure or different structures. For example, the electrode body disposed inside the laminated body has a three-layer structure in which the current collector is sandwiched between two electrode active material layers as shown in FIG. 5 or FIG. The electrode body may have a two-layer structure of one electrode active material layer and one layer current collector as described in FIG. 4 or FIG.

  In the step (E), as reference positions for alignment, as shown in FIG. 22, there are at least two positions on the outer periphery of each of the positive electrode body 10 and the negative electrode body 20. FIG. 22 is a top view of a laminate including the positive electrode body 10 and the negative electrode body 20 arranged so as to be in contact with the guide 40 of the alignment jig. FIG. 22 shows an example of a laminated body in which the positive electrode body 10 is arranged in the uppermost layer. The negative electrode body 20 may be disposed in the uppermost layer. In FIG. 22, the positive electrode body 10 has a positive electrode current collecting tab 14, and the negative electrode body 20 has a negative electrode current collecting tab 24. In FIG. 22, the positive electrode current collecting tab 14 and the negative electrode current collecting tab 24 are arranged in the same direction, but may be arranged in different directions as long as they do not hit the guide 40. As shown in FIG. 22, misalignment of the positive electrode body 10 and the negative electrode body 20 can be easily reduced by aligning at least two corresponding outer peripheral portions of the positive electrode body 10 and the negative electrode body 20 as a reference. Can do.

  Alignment may be performed with reference to three locations on the outer periphery of each of the positive electrode body 10 and the negative electrode body 20, or may be performed with reference to four or more locations.

  The alignment can be easily performed using an alignment jig having a guide as shown in FIG. For example, in the case where alignment is performed with reference to two corresponding outer peripheral portions of the positive electrode body 10 and the negative electrode body 20, the two guides 40 in contact with the two outer peripheral portions of the positive electrode body 10 and the negative electrode body 20 are provided. An alignment jig can be used. The alignment jig may have three or more guides 40, and the alignment jig guide 40 may be fixed or movable. The alignment jig may have a fixing portion that fixes the electrode body after alignment. When the positive electrode body 10 and the negative electrode body 20 are aligned using an alignment jig including two guides 40 as shown in FIG. 22, for example, the positive electrode body 10 and the negative electrode body 20 are first attached to one guide 40. Positioning may be performed so as to be in contact, and then positioning may be performed so that the positive electrode body 10 and the negative electrode body 20 are in contact with the other guide 40, or the positive electrode body 10 and the negative electrode body may be simultaneously applied to two guides. You may align so that 20 may touch. When positioning the positive electrode body 10 and the negative electrode body 20 against the guide 40, the positive electrode body 10 and the negative electrode body 20 are pushed toward the guide 40 from the opposite side so that the positive electrode body 10 and the negative electrode body 20 hit the guide 40. Alternatively, the positioning jig may be tilted and vibrated.

  In the step (E), the laminated body in which the one or more positive electrode bodies 10 and the one or more negative electrode bodies 20 are aligned is pressed to produce an all-solid battery.

  The laminated body in which the positive electrode body 10 and the negative electrode body 20 are aligned may be transferred from the alignment jig to the mold and pressed, or when the alignment jig also serves as the mold, the alignment jig You may press a laminated body.

  A press can be performed using a commercially available pressurization apparatus, and can perform isotropic pressure press, such as a uniaxial press or a cold isostatic press (CIP).

  As a preferable aspect of the pressing method, there is a uniaxial press that presses in the direction perpendicular to the laminated surface as exemplified in FIGS. 19 to 21, and it is more preferable to perform the uniaxial press while heating. The method of uniaxial pressing while heating can favorably improve the adhesion and densification of each layer, and can relatively shorten the pressurization time, which is industrially advantageous. A heated press plate (for example, a metal plate) is applied to the laminate as illustrated in FIGS. 19 to 21 and / or a mold containing the laminate as illustrated in FIGS. 19 to 21 is heated. Thus, pressing can be performed in a direction perpendicular to the stacking surface of the stack.

  The press pressure of the uniaxial press can be set to any pressure at which a laminate as illustrated in FIGS. 19 to 21 can be bonded to produce an all-solid battery. For example, in order to adhere each layer of the laminate, the pressing pressure can be preferably 50 to 1000 MPa, more preferably 80 to 600 MPa. The pressing temperature of the uniaxial press can be adjusted to an arbitrary temperature by heating a press plate (for example, a metal plate) of a pressing device and / or by heating a mold in which a laminated body is placed. Is preferably 80 to 160 ° C. The holding time of the pressing pressure of the uniaxial press is set to an arbitrary time during which the temperature is transmitted from the press plate (for example, metal plate) and / or the mold to the laminated body, and the laminated body is bonded to produce an all-solid battery. Preferably 10 seconds to 5 minutes, more preferably 30 seconds to 2 minutes.

  Another preferred embodiment of the pressing method is an isostatic press such as a cold isostatic press (CIP). The laminated body in which the positive electrode body and the negative electrode body are aligned can be put into a packaging material such as a laminate and vacuumed, and then pressed with a cold isostatic press (CIP). The conditions for cold isostatic pressing (CIP) can be the same as in step (C).

  In addition, the method which concerns on this invention includes the aspect which performs the process (A)-(E) by a separate process, the aspect performed continuously, or the aspect performed simultaneously. In addition, the method according to the present invention includes, for example, an embodiment in which the step (A) is performed after the step (B), an embodiment in which the steps (A) and (C) are performed after the steps (B) and (C), and a step (A ) To (C) are performed simultaneously, and at least one of them includes a positive electrode body and a negative electrode body covered with a solid electrolyte layer. In addition, the method according to the present invention includes an aspect in which one or more positive electrode bodies and one or more negative electrode bodies are stacked while being aligned in steps (D) and (E).

  In the method according to the present invention, preferably, steps (A) to (E) are repeated to produce two or more all-solid batteries, and (F) the produced two or more all-solid batteries are laminated, And aligning and pressing at least two locations on the outer periphery of each of the two or more all solid state batteries. In this case, the all-solid battery obtained by pressing and integrating the laminate including one or more positive electrode bodies and one or more negative electrode bodies is further laminated and aligned and pressed at a time in step (F). The positional deviation of the positive electrode body 10 and the negative electrode body 20 can be made smaller than when all layers are stacked and aligned and pressed.

  For example, when producing an all solid state battery including six positive electrode bodies 10 and six negative electrode bodies 20, the steps (A) to (E) are repeated, and the all solid state battery including two positive electrode bodies 10 and two negative electrode bodies 20 is obtained. In addition, in step (F), three all solid state batteries are stacked, aligned, and pressed to obtain an all solid state battery including six positive electrode bodies 10 and six negative electrode bodies 20. it can.

  In the method according to the present invention, more preferably, the steps (A) to (E) are repeated to produce two or more unit cells including one positive electrode body 10 and one negative electrode body 20, and (F) Laminating two or more produced single cells, and aligning and pressing at least two locations on the outer periphery of each of the laminated two or more single cells. In this case, an all solid state battery in which the positional deviation between the positive electrode body 10 and the negative electrode body 20 is further reduced can be obtained.

  For example, when producing an all solid state battery including six positive electrode bodies 10 and six negative electrode bodies 20, the steps (A) to (E) are repeated to obtain a single battery including one positive electrode body 10 and one negative electrode body 20. In the step (F), six unit cells are stacked, aligned, and pressed in step (F), whereby an all solid state battery including the six positive electrode bodies 10 and the six negative electrode bodies 20 can be obtained.

  As described above, according to the method according to the present invention, it is possible to easily reduce the positional deviation when the positive electrode body and the negative electrode body are stacked. According to the method of the present invention, the positive electrode body and the negative electrode body can be easily aligned even when a single battery including one positive electrode body and one negative electrode body is manufactured. Even when an all-solid battery having a laminated structure including two or more bodies is manufactured, the positive electrode body and the negative electrode body can be easily aligned.

  As the battery case that wraps the all-solid battery, a known laminate film that can be used in the all-solid battery can be used. Examples of such a laminate film include a resin laminate film, a film obtained by depositing a metal on a resin laminate film, and the like.

  The all solid state battery can take a desired shape such as a cylindrical shape, a square shape, a button shape, a coin shape, or a flat shape, but is not limited thereto.

  Embodiments 1 to 3 will be exemplified below as embodiments for carrying out the present invention. Embodiments 1 to 3 are shown for illustrative purposes, and the scope of the present invention is not limited to Embodiments 1 to 3.

(Embodiment 1)
Production of cathode body LiCo _1/3 Ni _1/3 Mn _1/3 O ₂ cathode active material particles having an average particle size of 4 μm, solid content ratio with respect to 100 parts by weight of cathode active material particles, 33.5 weight as solid electrolyte Of LiI-Li ₂ S—P ₂ S ₅ glass ceramics having an average particle size of 0.8 μm, 3 parts by weight of VGCF as a conductive auxiliary agent, and 1.5 parts by weight of hydrogenated butylene rubber as a binder are dispersed in heptane Can be made. A dispersion medium is put into a sample bottle, mixed for 30 seconds with an ultrasonic homogenizer (SMH, UH-50), and mixed for 30 minutes with a shaker (Shibata Kagaku, TTM-1) to obtain a slurry. Can do. The slurry is applied onto an Al foil having a thickness of 20 μm using a four-side applicator (manufactured by Dazai Equipment) and dried. Furthermore, the slurry can be similarly applied to the opposite surface of the Al foil and dried to prepare the positive electrode body 10 as shown in FIG.

Production of negative electrode body: Natural graphite-based carbon (manufactured by Mitsubishi Chemical) as the negative electrode active material, and 73 parts by weight of LiI-Li ₂ S-P ₂ S system as the solid electrolyte in a solid content ratio with respect to 100 parts by weight of the negative electrode active material Glass ceramics and 2.5 parts by weight of hydrogenated butylene rubber as a binder can be dispersed in heptane. The dispersion medium can be put in a sample bottle, mixed with an ultrasonic homogenizer for 30 seconds, and mixed with a shaker for 30 minutes to obtain a slurry. The slurry can be applied onto a 10 μm thick Cu foil using a four-side applicator and dried. Furthermore, the negative electrode body 20 as shown in FIG. 7 can be produced by coating and drying the slurry on the opposite surface of the Cu foil in the same manner.

Production of Solid Electrolyte Layer Disperse LiI-Li ₂ S—P ₂ S ₅ glass ceramic as a solid electrolyte and 1 part by weight of hydrogenated butylene rubber as a binder in heptane at a solid content ratio with respect to 100 parts by weight of the solid electrolyte. Can be made. The dispersion medium can be put in a sample bottle, mixed with an ultrasonic homogenizer for 30 seconds, and mixed with a shaker for 30 minutes to obtain a slurry. The prepared solid electrolyte layer slurry is impregnated into a polypropylene (PP) mesh material as a reinforcing material and dried to obtain a solid electrolyte layer.

Production of an all-solid battery A solid electrolyte layer 31 is laminated on both sides of the produced negative electrode body 20, uniaxial press is performed at a pressure of 600 MPa, punched to a predetermined size, and a negative electrode having a solid electrolyte layer 31 as shown in FIG. The body 20 can be obtained.

  The produced positive electrode body 10 can be punched into a smaller outer dimension than the negative electrode body 20 having the solid electrolyte layer 31, and the produced solid electrolyte layer can be punched into the same outer dimension as the negative electrode body 20 having the solid electrolyte layer 31. it can. As shown in FIG. 16, after the punched positive electrode body is disposed in the center of the punched solid electrolyte layer 30 and the positive electrode body is stacked so as to be sandwiched between the solid electrolyte layers 30, the packaging material is evacuated. Then, cold isostatic pressing (CIP) is performed at a pressure of 600 MPa to obtain a positive electrode body 10 having a protrusion 32 that is entirely covered with a solid electrolyte layer 30 as shown in FIG.

  As shown in FIG. 19, the positive electrode body 10 covered with the three solid electrolyte layers 30 and the negative electrode body 20 having the three solid electrolyte layers 31 are alternately stacked, and the position having two guides as shown in FIG. Using the alignment jig, alignment is performed with reference to two locations on the outer periphery of the negative electrode body 20 having the positive electrode body 10 and the solid electrolyte layer 31 covered with the solid electrolyte layer 30, and 120 ° C., 100 MPa, 3 minutes, A uniaxial press is performed, the positive electrode body 10 covered with the solid electrolyte layer 30 and the negative electrode body 20 having the solid electrolyte layer 31 are adhered, and an all-solid battery can be manufactured.

Encapsulation of all-solid-state battery The produced all-solid-state battery can be encapsulated in an aluminum laminate cell that includes a positive electrode tab and a negative electrode tab and whose inner surface is coated with a resin.

(Embodiment 2)
The same as in Embodiment 1 except that the negative electrode body is uniaxially pressed at a pressure of 600 MPa and not punched to a predetermined size without providing the solid electrolyte layer, thereby obtaining the negative electrode body 20 having a structure as shown in FIG. Thus, an all-solid battery can be obtained. As shown in FIG. 20, positive electrode bodies 10 and three negative electrode bodies 20 covered with three solid electrolyte layers 30 are alternately stacked, and an alignment jig having two guides as shown in FIG. 22 is used. Alignment is performed with reference to two locations of the outer periphery of the positive electrode body 10 and the negative electrode body 20 covered with the solid electrolyte layer 30, and uniaxial pressing is performed at 120 ° C., 100 MPa for 3 minutes, and the solid electrolyte layer 30 is covered. The all-solid battery can be manufactured by bonding the positive electrode body 10 and the negative electrode body 20.

(Embodiment 3)
The negative electrode body is punched to a predetermined outer dimension, the solid electrolyte layer is punched to a larger outer dimension, and the punched negative electrode body is disposed in the center of the punched solid electrolyte layer in the same manner as shown in FIG. A structure in which the negative electrode body is laminated so as to be sandwiched between solid electrolyte layers is put into a laminate packaging material and vacuum-evacuated, followed by cold isostatic pressing (CIP) at a pressure of 600 MPa, and the structure similar to FIG. An all-solid battery can be obtained in the same manner as in the first embodiment except that the negative electrode body 20 covered with the solid electrolyte layer 30 having the above is obtained. In this case, as shown in FIG. 15, the protruding portion 32 is enlarged so that the external dimensions of the positive electrode body 10 are larger than those of the first and second embodiments. Then, as shown in FIG. 21, the positive electrode body 10 covered with the three solid electrolyte layers 30 and the negative electrode body 20 covered with the three solid electrolyte layers 30 are alternately stacked, and two pieces as shown in FIG. Using an alignment jig having a guide, alignment is performed with reference to two positions of the outer periphery of the positive electrode body 10 covered with the solid electrolyte layer 30 and the negative electrode body 20 covered with the solid electrolyte layer 30, and 120 ° C. 100 MPa, uniaxial pressing is performed for 3 minutes, and the positive electrode body 10 covered with the solid electrolyte layer 30 and the negative electrode body 20 covered with the solid electrolyte layer 30 are adhered to obtain an all-solid battery.

DESCRIPTION OF SYMBOLS 100 All-solid-state battery 1 Positive electrode layer 2 Negative electrode layer 3 Solid electrolyte layer 4 Positive electrode collector 5 Negative electrode collector 10 Positive electrode body 11 Positive electrode active material layer 12 Positive electrode collector 13 External dimension of positive electrode body 14 Positive electrode current collection tab 15 Positive electrode Main body surface 20 Negative electrode body 21 Negative electrode active material layer 22 Negative electrode current collector 23 Negative electrode body external dimensions 24 Negative electrode current collector tab 25 Main surface of negative electrode body 30 Solid electrolyte layer 31 Solid electrolyte layer 32 Projection 33 Side surface of electrode body Part 34 Folding part 40 Guide 50 Rigid substrate

Claims (5)

(A) providing one or more positive electrode bodies including a positive electrode active material layer and a positive electrode current collector layer;
(B) a step of providing one or more negative electrode bodies including a negative electrode active material layer and a negative electrode current collector layer and having different outer dimensions with respect to the positive electrode body;
(C) Of the one or more positive electrode bodies and the one or more negative electrode bodies, at least a part of an electrode body having a smaller outer dimension is covered with a solid electrolyte layer, and the at least two portions of the side surface portion of the electrode body are from the end of the solid electrolyte layer to form a protruding portion formed, that closer to the outer dimension of the one or more positive electrode outer dimensions with the one or more negative electrode body by increasing the outside dimension of the electrode body as Engineering,
(D) The one or more positive electrode bodies and the one or more negative electrode bodies, at least one of which is covered with the solid electrolyte layer, are alternately laminated so that the solid electrolyte layer is disposed therebetween to form a laminate. And (E) aligning the one or more positive electrode bodies and the one or more negative electrode bodies with reference to at least two locations on the outer periphery thereof, pressing the laminate, and forming an all-solid battery. Manufacturing process,
A method for producing an all-solid battery. The manufacturing method according to claim 1 is repeated to produce two or more all-solid batteries, and (F) the two or more all-solid batteries are stacked, and each of the two or more stacked all-solid batteries is stacked. Aligning and pressing at least two locations on the outer periphery of the
A method for producing an all-solid battery. The manufacturing method according to claim 1 is repeated to produce two or more unit cells including one positive electrode body and one negative electrode body,
(F) stacking the two or more unit cells, aligning and pressing at least two locations on the outer periphery of each of the stacked two or more unit cells,
The manufacturing method of the all-solid-state battery of Claim 2 containing this.   All the external dimensions of the said positive electrode body provided at the said process (A) are smaller than the external dimension of the said negative electrode body provided at the said process (B). A method for producing a solid state battery.   The manufacturing method of the all-solid-state battery as described in any one of Claims 1-4 with which the said pressing includes uniaxial pressing, heating.

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