Positive electrode for secondary batteries

Abstract

To provide a positive electrode for secondary batteries with excellent cycle characteristics. [Solution] A positive electrode for a secondary battery, comprising a positive electrode current collector layer, a base film, a positive electrode active material layer, and The electrode has a cap layer, the underlayer has titanium nitride, and the positive electrode active material layer has lithium cobalt oxide. The positive electrode for secondary batteries has a cap layer containing titanium oxide. Titanium nitride is applied to the underlayer. This ensures sufficient conductivity while suppressing oxidation of the positive electrode current collector layer and diffusion of metal atoms. This can be achieved. Furthermore, by applying titanium dioxide to the cap layer, the relationship between the positive electrode active material layer and the electrolyte can be improved. This suppresses side reactions and disruption of the crystal structure of the active material, thereby improving cycle characteristics. ru.

Description

[Technical Field]

[0001] One aspect of the present invention relates to a product, a method, or a method of manufacture. Alternatively, the present invention relates to a process. This relates to machines, manufacturers, or compositions of matter. One aspect of the present invention relates to semiconductor devices, display devices, light-emitting devices, energy storage devices, lighting devices, electronic devices, Or relating to methods for manufacturing them.

[0002] In this specification, "electronic equipment" refers to all devices that have an energy storage device, and the energy storage device is All electronic devices, including electro-optical devices and information terminal devices with energy storage systems, are considered electronic equipment. [Background technology]

[0003] In recent years, lithium-ion secondary batteries, lithium-ion capacitors, air batteries, all-solid-state batteries, etc. The development of various energy storage devices is thriving, particularly high-power, high-capacity lithium-ion batteries. The demand for rechargeable batteries has expanded rapidly alongside the development of the semiconductor industry, and they represent a source of rechargeable energy. As a source of supply, it has become indispensable in today's information society.

[0004] Furthermore, along with the expansion of demand, there is a growing need for higher-performance lithium-ion secondary batteries. Therefore, efforts are being made to increase the capacity and improve the cycle characteristics of lithium-ion secondary batteries. Improvements are being made to the most active materials (for example, Patent Document 1).

[0005] Furthermore, development is underway on all-solid-state batteries, which are even safer than lithium-ion secondary batteries. The positive electrode, electrolyte, and negative electrode are formed by PVD (physical vapor deposition), CVD (chemical vapor deposition), etc. Thin-film secondary batteries are also a type of all-solid-state battery (for example, Patent Document 2). [Prior art documents]

Patent Document

[0006]

Patent Document 1

Patent Document 2

Non-Patent Document

[0007]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] In thin-film secondary batteries, there is room for improvement in various aspects such as charge-discharge characteristics, cycle characteristics, reliability, safety, or cost. For example, regarding cycle characteristics, as charge-discharge is repeated, the crystal structure of the positive electrode active material may collapse, which may lead to a decrease in charge-discharge capacity. Also, side reactions may occur at the interface between the positive electrode active material and the electrolyte, the interface between the positive electrode active material and the positive electrode current collector, etc., which may also lead to a decrease in charge-discharge capacity.

[0009] Therefore, one aspect of the present invention is to provide a positive electrode for a secondary battery in which side reactions are unlikely to occur at the interface between the positive electrode active material and the electrolyte, the interface between the positive electrode active material and the positive electrode current collector, etc., even when charge-discharge is repeated. <​​​​One of the challenges is to provide a positive electrode for secondary batteries with excellent charge-discharge cycle characteristics. One of the challenges is to provide a positive electrode for secondary batteries with a large charge / discharge capacity. It shall be one of the following. Alternatively, a positive electrode for a secondary battery in which the decrease in capacity during the charge-discharge cycle is suppressed. One of the challenges is to provide a secondary battery with excellent charge-discharge cycle characteristics. One of the challenges is to provide a secondary battery with a large charge / discharge capacity. One objective is to provide a safe or highly reliable secondary battery. .

[0010] Alternatively, one aspect of the present invention relates to a novel substance, active material particles, energy storage device, or a method for producing the same. One of the objectives is to provide [this].

[0011] Furthermore, the description of these problems does not preclude the existence of other problems. The embodiments do not need to solve all of these problems. It is possible to extract other issues from the description of the requested terms. [Means for solving the problem]

[0012] In one aspect of the present invention, the crystal structure is made less prone to collapse, or side reactions are suppressed, and the cycle characteristics are improved. To improve performance, a cap layer was added on the positive electrode active material layer.

[0013] One aspect of the present invention is a positive electrode for a secondary battery, comprising a base film, a positive electrode active material layer, and a cap layer. , and at least one of the underlayer and cap layer has titanium oxide nitride, positive electrode active The material layer contains lithium cobalt oxide, and the cap layer contains a titanium compound containing oxygen. This is the positive electrode for the next battery.

[0014] Alternatively, in the above, the crystal structure of the undercoat film and the crystal structure of the positive electrode active material layer are either It is preferable that the surface has an arrangement of only anions.

[0015] Furthermore, in the above, both the base film and the positive electrode active material layer have alternating arrangements of cations and anions. It is preferable that the crystal structure has a series of aligned crystals.

[0016] Furthermore, one aspect of the present invention relates to a secondary battery having the above-mentioned positive electrode for secondary batteries, a solid electrolyte, and a negative electrode. It is a battery.

[0017] Another aspect of the present invention is an electronic device having the above-mentioned secondary battery.

[0018] Furthermore, in one aspect of the present invention, the secondary battery described above, a positive electrode, a negative electrode, an electrolyte, and a separator are It is an electronic device having a lithium-ion secondary battery. [Effects of the Invention]

[0019] According to one aspect of the present invention, even after repeated charging and discharging, the interface between the positive electrode active material and the electrolyte, and the positive electrode active material This provides a positive electrode for secondary batteries that is less prone to side reactions at the interface with the positive electrode current collector. This provides a positive electrode for secondary batteries that maintains its crystal structure even after repeated charging and discharging. Furthermore, it is possible to provide a positive electrode for secondary batteries with excellent charge-discharge cycle characteristics. It is possible to provide a positive electrode for secondary batteries with a large capacity. Also, the capacity in the charge-discharge cycle. This provides a positive electrode for secondary batteries in which the decrease in quantity is suppressed. Furthermore, it offers advantages in charge-discharge cycle characteristics. We can provide a secondary battery with excellent performance. Furthermore, we can provide a secondary battery with a large charge / discharge capacity. It is possible to provide safe and reliable rechargeable batteries.

[0020] Furthermore, according to one aspect of the present invention, a novel substance, active material particles, energy storage device, or method for producing the same may be provided. We can provide this.

[0021] Furthermore, the description of these effects does not preclude the existence of other effects. The embodiment does not necessarily have to have all of these effects. Furthermore, other effects are... This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings Furthermore, it is possible to extract effects other than those mentioned above from the claims and other descriptions. [Brief explanation of the drawing]

[0022] [Figure 1] Figures 1A to 1C are perspective views of a positive electrode according to one embodiment of the present invention. [Figure 2] Figures 2A and 2B illustrate the crystal structure of a positive electrode according to one embodiment of the present invention. [Figure 3] Figures 3A to 3C illustrate a stacked structure of a secondary battery according to one embodiment of the present invention. [Figure 4] Figure 4A is a top view showing one aspect of the present invention, and Figures 4B to 4D are cross-sectional views showing one aspect of the present invention. [Figure 5] Figures 5A and 5C are top views showing one aspect of the present invention, and Figures 5B and 5D are cross-sectional views showing one aspect of the present invention. [Figure 6] Figure 6A is a top view showing one aspect of the present invention, and Figure 6B is a cross-sectional view showing one aspect of the present invention. [Figure 7] Figure 7A is a top view showing one aspect of the present invention, and Figure 7B is a cross-sectional view showing one aspect of the present invention. [Figure 8] Figure 8 is a diagram illustrating the manufacturing flow of a secondary battery according to one embodiment of the present invention. [Figure 9] Figures 9A and 9B are top views illustrating one embodiment of the present invention. [Figure 10]Figure 10 is a cross-sectional view showing one aspect of the present invention. [Figure 11] Figure 11 is a diagram illustrating the manufacturing flow of a secondary battery according to one embodiment of the present invention. [Figure 12] Figure 12 is a schematic top view of a secondary battery manufacturing apparatus. [Figure 13] Figure 13 is a cross-sectional view of a part of a secondary battery manufacturing apparatus. [Figure 14] Figure 14A is a perspective view showing an example of a battery cell. Figure 14B is a perspective view of the circuit. Figure 14C is a perspective view showing the battery cell and circuit superimposed. [Figure 15] Figure 15A is a perspective view showing an example of a battery cell. Figure 15B is a perspective view of the circuit. Figures 15C and 15D are perspective views showing the battery cell and circuit superimposed. [Figure 16] Figure 16A is a perspective view of a battery cell. Figure 16B is a diagram showing an example of an electronic device. [Figure 17] Figures 17A to 17C show examples of electronic devices. [Figure 18] Figures 18A to 18C show examples of electronic devices. [Figure 19] Figures 19A to 19D show examples of electronic devices. [Figure 20] Figure 20A shows a part of a system according to one aspect of the present invention. Figure 20B shows an example of an electronic device according to one aspect of the present invention. [Figure 21] Figure 21A is a schematic diagram of an electronic device according to one aspect of the present invention. Figure 21B is a diagram showing a part of the system, and Figure 21C is an example of a perspective view of a portable data terminal used in the system. [Figure 22] Figures 22A and 22B are graphs showing the charge and discharge characteristics of the secondary battery according to Example 1. [Figure 23] Figures 23A and 23B are graphs showing the cycle characteristics of the secondary battery according to Example 1. [Figure 24] Figure 24 is a cross-sectional TEM image of the positive electrode according to Example 2. [Figure 25]Figure 25A is a cross-sectional TEM image of the positive electrode active material layer according to Example 2. Figure 25B is a micro-electron diffraction image of the positive electrode active material layer according to Example 2. [Figure 26] Figures 26A and 26B show micro-electron diffraction patterns of the positive electrode active material layer according to Example 2. [Figure 27] Figure 27 is a cross-sectional TEM image of the positive electrode according to Example 2. [Figure 28] Figures 28A and 28B are cross-sectional TEM images of the positive electrode according to Example 2. [Figure 29] Figure 29 shows the EELS spectrum of the positive electrode active material layer according to Example 2. [Figure 30] Figure 30 is a cross-sectional TEM image of the positive electrode according to Example 2. [Figure 31] Figures 31A and 31B are cross-sectional TEM images of the positive electrode according to Example 2. [Figure 32] Figure 32 shows the EELS spectrum of the positive electrode active material layer according to Example 2. [Figure 33] Figure 33A is a cross-sectional TEM image of the positive electrode active material layer according to Example 2. Figure 33B is a micro-electron diffraction image of the positive electrode active material layer according to Example 2. [Figure 34] Figures 34A and 34B show micro-electron diffraction patterns of the positive electrode active material layer according to Example 2. [Figure 35] Figure 35A is a cross-sectional TEM image of the positive electrode active material layer according to Example 2. Figure 35B is a micro-electron diffraction image of the positive electrode active material layer according to Example 2. [Figure 36] Figures 36A and 36B show micro-electron diffraction patterns of the positive electrode active material layer according to Example 2. [Figure 37] Figure 37 is a graph showing the charge-discharge cycle characteristics of the secondary battery according to Example 2. [Figure 38] Figures 38A and 38B illustrate the impedance measurement of a secondary battery according to Example 2. [Figure 39] Figure 39 shows the impedance measurement results of the secondary battery according to Example 2. [Figure 40] Figure 40 shows the impedance measurement results of the secondary battery according to Example 2. [Modes for carrying out the invention]

[0023] The embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is... Not limited to the following description, the form and details can be modified in various ways, as any person skilled in the art would know. This is easily understood. Furthermore, the present invention shall be interpreted as being limited to the contents of the embodiments described below. It's not something that can be done.

[0024] Furthermore, Miller indices are used to indicate crystal planes and directions in this specification. Individual surfaces are represented by ( ). Directions are represented by [ ]. Reciprocal lattice points use the same indices, but This is not used. Crystal planes, directions, and space groups are notated in crystallography by adding a superscript bar to the number. However, due to the limitations of application notation in this specification, instead of placing a bar above the number, a - is placed before the number. It is sometimes expressed with a minus sign.

[0025] In this specification, etc., the layered rock salt type crystal structure of a composite oxide containing lithium and a transition metal This structure has a rock salt-type ionic arrangement in which cations and anions are arranged alternately, and it contains transition metals and Because lithium is arranged in a regular pattern to form a two-dimensional plane, two-dimensional diffusion of lithium is possible. This refers to the crystal structure. It may contain defects such as vacancies in cations or anions. Also, layers... Strictly speaking, the rock salt crystal structure is a structure in which the lattice of the rock salt crystal is distorted. be.

[0026] Furthermore, in this specification, a rock salt-type crystal structure is defined as a structure in which cations and anions are arranged alternately. This refers to a structure that contains certain elements. It is also acceptable for there to be deficiencies in cations or anions.

[0027] Layered rock salt crystals, and the anions of rock salt crystals, have a cubic close-packed structure (face-centered cubic lattice structure). When these come into contact, the cubic close-packed structure composed of anions coincides. Crystal planes exist. However, the space group of layered rock salt crystals is R-3m, and the space group of rock salt is F. Since it differs from m-3m, the Miller indices of crystal planes that satisfy the above conditions are for layered rock salt crystals and rock This is different in salt-type crystals. In this specification, in layered rock salt-type crystals and rock salt-type crystals, anions ion When the cubic close-packed structures formed by these elements coincide, the orientation of the crystals is said to be approximately the same. There are cases where this is the case.

[0028] The approximate agreement of the crystal orientation in the two regions can be seen in TEM (transmission electron microscope) images and STEM images. (Scanning transmission electron microscope) image, HAADF-STEM (High-angle scattering annular dark-field scanning transmission electron microscope) This can be determined from images such as microscopic images and ABF-STEM (annular bright-field scanning transmission electron microscope) images. Yes, it is possible. X-ray diffraction (XRD), electron diffraction, neutron diffraction, etc., can also be used as criteria for judgment. If the crystal orientation is roughly consistent, then cations and anions can be seen linearly in TEM images, etc. It can be observed that the difference in direction between alternating rows is 5 degrees or less, or 2.5 degrees or less. Note that light elements such as oxygen and fluorine may not be clearly visible in TEM images, etc. Yes, but in that case, the alignment of the metal elements can be determined by their arrangement.

[0029] Furthermore, in this specification, the theoretical capacity of the positive electrode active material refers to the insertable and removable capacity of the positive electrode active material. This refers to the amount of electricity that would be generated if all lithium were to be desorbed. For example, the theoretical capacity of LiCoO2 is 27 The theoretical capacity of LiNiO2 is 274mAh / g, and the theoretical capacity of LiMn2O4 is 4mAh / g. The capacity is 148mAh / g.

[0030] Furthermore, in this specification, etc., the charging depth when all insertable and removable lithium is inserted. Let 0 be the charge depth when all the insertable and detachable lithium in the positive electrode active material has been detached, and 1 be the charge depth when 0 is the charge depth when 1 is the charge depth when all the insertable and detachable lithium in the positive electrode active material has been detached. Let's leave it at that.

[0031] Furthermore, in this specification, the term "parallel planes" refers only to planes that are mathematically strictly parallel. Rather, it refers to the angle between two surfaces being 5° or less, or 2.5° or less.

[0032] (Embodiment 1) A positive electrode for a secondary battery according to one aspect of the present invention will be described using Figure 1.

[0033] Figure 1A is a perspective view of an example of a positive electrode 100 according to one aspect of the present invention. The positive electrode 100 is a positive electrode cluster It comprises an electrode body 103, a base film 104, a positive electrode active material layer 101, and a cap layer 102.

[0034] The undercoat 104 is provided between the positive electrode current collector 103 and the positive electrode active material layer 101. It has the function of increasing the conductivity between the positive electrode current collector 103 and the positive electrode active material layer 101. Or positive electrode Oxidation of the positive electrode current collector 103 by oxygen contained in the active material layer 101, etc., or the positive electrode current collector 10 It has the function of suppressing side reactions such as the diffusion of metal atoms contained in 3 into the positive electrode active material layer 101. It either does so, or it has the function of stabilizing the crystal structure of the positive electrode active material layer 101.

[0035] It is preferable to use a conductive material as the base film 104. It is preferable to use a pyramidal material, for example, titanium oxide or titanium nitride, which are titanium compounds. Titanium oxide partially substituted with nitrogen, titanium nitride partially substituted with oxygen, or titanium oxide nitride Titanium (TiO x Ny , 0 < x < 2, 0 < y < 1), etc. can be applied. Among them, titanium nitride is particularly preferred because it has high conductivity and a high function of suppressing oxidation. Titanium nitride is particularly preferred because it has high conductivity and a high function of suppressing oxidation.

[0036] The cap layer 102 is provided on the positive electrode active material layer 101. The cap layer 102 has a function of suppressing the side reaction between the positive electrode active material layer 101 and the electrolyte. Or it has a function of stabilizing the crystal structure possessed by the positive electrode active material layer 101. The cap layer 102 has a function of suppressing the side reaction between the positive electrode active material layer 101 and the electrolyte. Or it has a function of stabilizing the crystal structure possessed by the positive electrode active material layer 101. The cap layer 102 has a function of suppressing the side reaction between the positive electrode active material layer 101 and the electrolyte. Or it has a function of stabilizing the crystal structure possessed by the positive electrode active material layer 101.

[0037] It is preferable to use a titanium compound as the cap layer 102. For example, titanium oxide, titanium nitride, titanium oxide partially substituted with nitrogen, titanium nitride partially substituted with oxygen, or titanium oxynitride (TiO x N y , 0 < x < 2, 0 < y < 1) is preferably used. Titanium and oxygen are materials that can be contained in the solid electrolyte. Therefore, titanium oxide is particularly suitable as the cap layer 102. Titanium oxide is particularly suitable as the cap layer 102.

[0038] In this specification, etc., the electrolyte includes not only the solid electrolyte, but also the electrolyte solution in which a lithium salt is dissolved in a liquid solvent and the electrolyte solution in which a lithium salt is dissolved in a gel-like compound. It is also assumed to include the electrolyte solution in which a lithium salt is dissolved in a liquid solvent and the electrolyte solution in which a lithium salt is dissolved in a gel-like compound. It is also assumed to include the electrolyte solution in which a lithium salt is dissolved in a liquid solvent and the electrolyte solution in which a lithium salt is dissolved in a gel-like compound.

[0039] The positive electrode active material layer 101 has lithium, transition metal M, and oxygen. The positive electrode active material layer 10 1 may be said to have a composite oxide containing lithium and transition metal M.

[0040] As the transition metal M possessed by the positive electrode active material layer 101, it is preferable to use a metal that can form a layered rock salt type composite oxide belonging to the space group R-3m together with lithium. As the transition metal M, for example, one or more of manganese, cobalt, and nickel can be used. For example, one or more of manganese, cobalt, and nickel can be used. In other words, the positive electrode active material layer 101 may use only cobalt as the transition metal, or You may use only nickel, or two types, cobalt and manganese, or cobalt and nickel. You may use two types, or you may use three types: cobalt, manganese, and nickel. In other words, correct The highly active material layer 101 consists of lithium cobalt oxide, lithium nickel oxide, and a portion of cobalt. Lithium cobalt oxide with cancer, cobalt in which some of the cobalt is replaced by nickel. Lithium oxides, such as lithium nickel-manganese-cobalt oxide, contain lithium and transition metal M. It can have a complex oxide.

[0041] In addition to the above, the positive electrode active material layer 101 also contains magnesium, fluorine, aluminum, and other materials. It may also contain elements other than the transition metal M. These elements may be present in the positive electrode active material layer 101. This may further stabilize the crystal structure of the material. In other words, the positive electrode active material layer 101 is magnesium Lithium cobalt oxide with added calcium and fluorine, magnesium and fluorine added. Lithium nickel-cobalt oxide, magnesium and fluorine-added cobalt - Lithium aluminum oxide, nickel-cobalt-lithium aluminum oxide, magnesium This has lithium nickel-cobalt-aluminate, etc., with added fluorine and other properties. It is possible.

[0042] The positive electrode active material layer 101 is lithium, cobalt, nickel, aluminum, magnesium, acid If it contains fluorine and other elements, the atomic ratio of cobalt in the positive electrode active material layer 101 is set to 100. In this case, the atomic ratio of nickel is preferably, for example, 0.05 or more and 2 or less, and 0.1 or more and 1 A value of 0.5 or less is more preferable, and a value of 0.1 to 0.9 is even more preferable. (Positive electrode active material layer 101) When the atomic ratio of cobalt in a given material is set to 100, the atomic ratio of aluminum is, for example, 0. Preferably between 0.5 and 2, more preferably between 0.1 and 1.5, and between 0.1 and 0.9. The lower is even more preferable. Assuming the atomic ratio of cobalt in the positive electrode active material layer 101 is 100 The atomic ratio of magnesium is preferably, for example, 0.1 to 6, and 0.3 to 3. More preferable. Also, when the atomic ratio of magnesium in the positive electrode active material layer 101 is set to 1. The atomic ratio of fluorine is preferably, for example, 2 or more and 3.9 or less.

[0043] Having nickel, aluminum, and magnesium in the concentrations described above allows for high voltage Therefore, it can maintain a stable crystal structure even after repeated charging and discharging. A positive electrode active material layer 101 with excellent cycle characteristics can be obtained.

[0044] The molar concentrations of cobalt, nickel, aluminum, and magnesium are, for example, inductively bonded It can be evaluated by radima mass spectrometry (ICP-MS). The molar concentration of fluorine is For example, it can be evaluated by glow discharge mass spectrometry (GD-MS).

[0045] <First principles calculation> Here, when lithium cobalt oxide is used for the positive electrode active material layer 101, the positive electrode active material layer 101 and The results of calculations regarding the crystalline structure of the interface of the undercoat 104 are explained using Figure 2.

[0046] Figure 2A shows the case where titanium nitride is applied as the undercoat 104. Titanium nitride is a space group It has a rock salt-type crystal structure belonging to Fm-3m, and lithium cobalt oxide belongs to space group R-3m. The calculation was performed assuming that it has a layered rock salt type crystal structure. The (111) plane of titanium nitride and cobal The lithium trioxide layers are stacked so that their (001) planes are parallel.

[0047] Figure 2B shows the case where titanium dioxide is applied as the base film 104. Titanium dioxide is a space group. It has a rutile-type crystal structure belonging to P42 / mnm, and lithium cobaltate is in space group R-3. The calculation was performed assuming that it has a layered rock salt type crystal structure belonging to m. The (100) face of titanium oxide and The lithium cobalt oxide layers are stacked so that their (001) planes are parallel.

[0048] All figures show an excerpt of the interface between the positive electrode active material layer 101 and the base film 104. Other calculation conditions The details are shown in Table 1.

[0049] [Table 1]

[0050] In Figure 2A, where titanium nitride is applied as the undercoat 104, the Ti-O distance is 2.03 Å, T The iN distance was 1.93 Å, the Co-O distance was 2.25 Å, and the Co-N distance was 2.21 Å. Note that 1 Å = 10 -10 It is m.

[0051] In the rock salt type crystal structure belonging to space group Fm-3m, the plane where only anions are arranged is (11 1) Present on a plane parallel to the (111) plane. In titanium nitride, only nitrogen atoms exist on a plane parallel to the (111) plane. They are arranged. In the layered rock salt crystal structure belonging to space group R-3m, only anions are arranged. The plane that does this exists on a plane parallel to the (001) plane. In lithium cobalt oxide, the (001) plane and Only oxygen atoms are arranged on the parallel planes.

[0052] When the (111) plane of titanium nitride and the (001) plane of lithium cobalt oxide are parallel, When the planes where only anions are arranged become parallel, the crystal structure tends to become more stable.

[0053] Furthermore, there are rock salt type crystal structures belonging to space group Fm-3m and layered rock salt type structures belonging to space group R-3m. All of these crystal structures can be described as having a crystal structure in which cations and anions are arranged alternately. Therefore, on titanium nitride with a rock salt-type crystal structure, cobalt oxide with a layered rock salt-type crystal structure is placed. When thium is layered, the crystal orientations of the base film 104 and the positive electrode active material layer 101 tend to roughly coincide. stomach.

[0054] On the other hand, in the case of Figure 2B, where titanium oxide is applied as the undercoat 104, the Ti-O distance is 2.15 The Å and Co-O distance was 1.91 Å. Titanium oxide with a rutile-type crystal structure has an oxygen atom They do not align on a plane parallel to the (100) plane. Therefore, compared to titanium nitride, layered rock It may have a low ability to stabilize the salt-type crystal structure.

[0055] Thus, lithium cobalt oxide having a layered rock salt-type crystalline structure is used in the positive electrode active material layer 101. In this case, titanium nitride is particularly suitable as the undercoat 104.

[0056] Figure 1B is a perspective view of another example of the positive electrode 100, which is one embodiment of the present invention. Positive electrode shown in Figure 1B The 100 has a positive electrode current collector 103, a positive electrode active material layer 101, and a cap layer 102. The positive electrode 100 does not necessarily have to have an undercoat 104. Even without that, the secondary battery has sufficiently improved cycle characteristics due to having the cap layer 102. It may be possible.

[0057] Figures 1A and 1B describe the positive electrode, where the positive electrode current collector 103 serves both as a current collector and a substrate. As stated above, the present invention is not limited to this embodiment. Figure 1C shows a positive electrode 100 in one embodiment of the present invention. This is a perspective view of another example. As shown in Figure 1C, a positive electrode current collector 103 is placed on the substrate 110, below A positive electrode 100 is fabricated by depositing a ground film 104, a positive electrode active material layer 101, and a cap layer 102. That is also acceptable.

[0058] This embodiment can be implemented in appropriate combination with other embodiments.

[0059] (Embodiment 2) In this embodiment, using Figures 3 to 8, we will show the positive electrode for the secondary battery described in Embodiment 1. This section will explain secondary batteries and how to manufacture them.

[0060] [Configuration of a secondary battery] Figure 3A shows the stacked structure of a secondary battery 200 having a positive electrode 100 for a secondary battery according to one embodiment of the present invention. This is a diagram illustrating an example.

[0061] The secondary battery 200 is a thin-film battery and has a positive electrode 100 as described in the previous embodiment, and positive electrode 1 A solid electrolyte layer 203 is formed on 00, and a negative electrode 212 is formed on the solid electrolyte layer 203. The electrode 212 has a negative electrode current collector 205 and a negative electrode active material layer 204. Also, as shown in Figure 3A The negative electrode 212 preferably has a base film 214 and a cap layer 209.

[0062] The undercoat 214 is provided between the negative electrode current collector 205 and the negative electrode active material layer 204. It has the function of increasing conductivity between the negative electrode current collector 205 and the negative electrode active material layer 204. It has the function of suppressing excessive expansion of the active material layer. Or the negative electrode current collector 205 and the negative electrode active material layer It has the function of suppressing the side reaction of 204.

[0063] As the base film 214, it is preferable to use a material having conductivity. Also, it is preferable to use a material that can suppress excessive expansion of the negative electrode active material layer. It is also preferable to use a material that can easily suppress side reactions. For example, titanium compounds such as titanium oxide, titanium nitride, titanium oxide partially substituted with nitrogen, titanium nitride partially substituted with oxygen, or titanium oxynitride (Ti O x x N y y, 0 < x < 2, 0 < y < 1) is preferable. In particular, titanium nitride is highly preferable because it has high conductivity and a high function of suppressing side reactions.

[0064] The cap layer 209 is provided between the negative electrode active material layer 204 and the solid electrolyte layer 203. The cap layer 209 has a function of suppressing side reactions between the negative electrode active material layer 204 and the solid electrolyte layer 203.

[0065] As the cap layer 209, it is preferable to use titanium or a titanium compound. Examples of the titanium compound include titanium oxide, titanium nitride, titanium oxide partially substituted with nitrogen, titanium nitride partially substituted with oxygen, or titanium oxynitride (TiO x x y N y, 0 < x < 2, 0 < y < 1) is preferable. Titanium is a material that can be contained in the solid electrolyte. Therefore, titanium and titanium compounds are particularly suitable as the cap layer 209.

[0066] As the negative electrode active material layer 204, silicon, carbon, titanium oxide, vanadium oxide, indium oxide, zinc oxide, tin oxide, nickel oxide, etc. can be used. Also, materials that alloy with lithium such as tin, gallium ium, aluminum, etc. can be used. Also, these alloying Metal oxides can also be used. Furthermore, lithium titanium oxide (Li4Ti5O) may also be used. 12 , L Materials such as iTi2O4 may be used, but among them, materials containing silicon and oxygen (SiO2O4) may be used. x film (Also known as) is preferred. Furthermore, lithium metal may be used as the negative electrode active material layer 204. Alternatively, mixtures of these materials may be used. For example, a mixture of silicon particles and carbon is a reliable material. It is suitable because it has good reliability and a relatively high energy density per unit volume.

[0067] The solid electrolyte layer 203 is provided between the positive electrode 100 and the negative electrode 212. As for materials, Li 0.35 La 0.55 TiO3, La (2 / 3-A) Li 3A TiO 3、 Li3PO 4、 LixPO (4-B) N B , WhiteNb (1-A) Ta (A) WO6, Li7La3Zr2O 12 ,Li (1+A) Al (A) Ti (2-A) (PO4)3, L i (1+A) Al (A) Ge (2-A) Examples include (PO4)3 and LiNbO2. Oh, A>0, B>0. For film deposition methods, sputtering and vapor deposition can be used. can.

[0068] It is preferable to use a titanium-containing compound for the solid electrolyte layer 203. The positive electrode 100 has Since the cap layer 102 and the cap layer 209 of the negative electrode 212 have titanium, Using a titanium-containing material for the solid electrolyte layer 203 allows for the simple fabrication of a secondary battery. It is possible.

[0069] Also, SiO C (0 < C ≤ 2) can also be used as the solid electrolyte layer 203. SiO C (0 < C ≤ 2) is used as the solid electrolyte layer 203, and further S is used as the negative electrode active material layer 204 iO C (0 < C ≤ 2) may be used. In this case, the ratio of silicon to oxygen in SiO C (O / Si) is preferably higher in the solid electrolyte layer 203. With this configuration, conduction ions (especially lithium ions) diffuse easily in the solid electrolyte layer 203, and conduction ions (especially lithium ions) are easily desorbed or accumulated in the negative electrode active material layer 2 04, so a solid secondary battery with good characteristics can be obtained. As described above, by using materials composed of the same components for the solid electrolyte layer 203 and the negative electrode active material layer 204, a secondary battery can be easily fabricated .

[0070] Also, the solid electrolyte layer 203 may have a laminated structure. When laminating, a material obtained by adding nitrogen to lithium phosphate (Li3PO4) (Li3PO N (4-Z) : also called LiPON Z ) may be laminated. Note that Z > 0 .

[0071] Also, as shown in FIG. 3B, a secondary battery 200 having a negative electrode 212 in which a plurality of negative electrode active material layers 204 and cap layers 209 are laminated may be used. By laminating a plurality of negative electrode active material layers 204 and cap layers 209, the capacity can be improved while suppressing excessive expansion of the negative electrode 212 . At this time, the cap layer 209 in contact with the solid electrolyte layer 203 and the cap layer 209 sandwiched between the negative electrode active material layers 20 4 may be made of the same material or different materials . . For example, titanium dioxide is used in the cap layer 209 that is in contact with the solid electrolyte layer 203, and the negative electrode active material Titanium nitride may be used for the cap layer 209 sandwiched between layers 204.

[0072] Furthermore, as shown in Figure 3C, multiple positive electrode active material layers 101 and cap layers 102 are stacked together. A secondary battery 200 having electrode 100 may also be used. Positive electrode active material layer 101 and cap layer 102 By stacking multiple layers, the capacity is improved while the crystal structure of the positive electrode active material layer 101 is This can suppress collapse. At this time, the cap layer in contact with the solid electrolyte layer 203 102 and the cap layer 102 sandwiched between the positive electrode active material layer 101 may be made of the same material. The materials may be different. For example, the cap layer 102 in contact with the solid electrolyte layer 203 may be acid Titanium oxide is used, and titanium nitride is used for the cap layer 102 sandwiched between the positive electrode active material layers 101. That's good too.

[0073] Figures 4A and 4B show a more specific example of a secondary battery 200 according to one embodiment of the present invention. Next, I will describe the secondary battery 200 formed on the substrate 110.

[0074] Figure 4A is a top view, and Figure 4B is a cross-sectional view taken along the line A-A' in Figure 4A. Secondary power The battery 200 is a thin-film battery, and as shown in Figure 4B, it is mounted on the substrate 110 as described in the previous embodiment. A positive electrode 100 is formed, and a solid electrolyte layer 203 is formed on the positive electrode 100, and the solid electrolyte layer 2 A negative electrode 210 is formed on 03. The negative electrode 210 consists of a negative electrode current collector 205 and an underlayer 214 It also has a negative electrode active material layer 204 and a cap layer 209.

[0075] Furthermore, the secondary battery 200 has a positive electrode 100, a solid electrolyte layer 203, and a protective layer on the negative electrode 210. It is preferable that 206 is formed.

[0076] The films forming these layers can each be formed using a metal mask. Using the Tutter method, the positive electrode current collector 103, the undercoat 104, the positive electrode active material layer 101, and the cap layer 10 2. Solid electrolyte layer 203, cap layer 209, negative electrode active material layer 204, base film 214, negative electrode The current collector 205 can be selectively formed. In addition, a metal mask can be formed using the co-evaporation method. By using this method, a solid electrolyte layer 203 may be selectively formed.

[0077] As shown in Figure 4A, a portion of the negative electrode current collector 205 and the positive electrode current collector 103 are exposed at the negative electrode end. It forms the sub-part and the positive terminal part. The area other than the negative terminal part and the positive terminal part is protected It is covered by layer 206.

[0078] In Figures 4A and 4B, the positive electrode current collector 103, the base film 104, the positive electrode active material layer 101, and A solid electrolyte layer 203 and a negative electrode active material layer 204 are placed on the positive electrode 100 which has a cap layer 102. A configuration in which the negative electrode current collector 205 is stacked in order has been described, but one aspect of the present invention is It's not limited to that.

[0079] As shown in Figure 4C, the secondary battery 200 has a positive electrode current collector 103 and a positive electrode active material layer 101. The positive electrode 100 may not have a base film 104. Also, the base film 214 and the cap may The negative electrode 210 may not have a purifying layer 209.

[0080] Furthermore, in one aspect of the present invention, both the positive and negative electrodes of the secondary battery are composed of an active material layer and a cap. It may have a layered structure. For example, as shown in Figure 4D, the secondary battery 200 is a negative electrode The negative electrode 210 may have multiple stacked active material layers 204 and cap layers 209. Even if the positive electrode 100 has multiple layers of positive electrode active material layer 101 and cap layer 102 stacked on top of each other, stomach.

[0081] Furthermore, as shown in Figures 5A and 5B, a secondary battery according to one embodiment of the present invention comprises a negative electrode current collector layer and a negative electrode current collector layer. A secondary battery 201 may also have a negative electrode 211 that also serves as the electrode active material layer. Figure 5A shows a secondary battery This is a top view of pond 201, and Figure 5B is a cross-sectional view taken along the line B-B' in Figure 5A. Negative electrode By using a negative electrode 211 that serves as both the current collector layer and the negative electrode active material layer, the process is simplified and productivity is increased. It can be used as a secondary battery. Furthermore, it can be used as a secondary battery with high energy density. .

[0082] Furthermore, as shown in Figures 5C and 5D, in one embodiment of the present invention, the secondary battery has a fixed negative electrode 210. A secondary battery 202 may be formed by stacking an electrolyte layer 203 and a positive electrode 100. (Figure 5C) Figure 5C is a top view of the secondary battery 202, and Figure 5D is a cross-sectional view taken along the line C-C' in Figure 5C. ru.

[0083] Furthermore, in Figures 4 and 5, not only the positive electrode but also the solid electrolyte layer and the negative electrode are formed from thin films. Although a secondary battery has been described, the present invention is not limited to this. One aspect of the present invention is: It may also be a secondary battery having an electrolyte. It may also be a secondary battery having a negative electrode that also serves as a material layer. Alternatively, a powdered negative electrode active material may be used for negative electrode current collection. It may also be a secondary battery having a negative electrode made by coating a body.

[0084] A secondary battery 230 having an electrolyte is shown in Figures 6A and 6B. Figure 6A is a top view, and 6B is a cross-sectional view taken along the line D-D' in Figure 6A.

[0085] As shown in Figure 6B, the secondary battery 230 has a positive electrode 100 on the substrate 110 and a negative electrode on the substrate 111. It has a negative electrode 212, a separator 220, an electrolyte 221, and an outer casing 222. The negative electrode current collector 205, the negative electrode active material layer 204, and the cap layer 209 of component 2 are formed as thin films. It is being done.

[0086] Also, as shown in Figure 6A, the secondary battery 230 has lead electrodes 223a and 223b It has. Lead electrode 223a is electrically connected to positive electrode current collector 103. Lead electrode 2 23b is electrically connected to the negative electrode current collector 205. Lead electrode 223a and lead electrode A portion of 223b is extended outside the outer casing 222.

[0087] Figure shows a secondary battery 231 having an electrolyte and a negative electrode 211 that serves as both a negative electrode current collector layer and a negative electrode active material layer. This is shown in Figures 7A and 7B. Figure 7A is a top view, and Figure 7B is a section cut along the line E-E' in Figure 7A. This is a cross-sectional view.

[0088] As shown in Figure 7B, the secondary battery 231 has a positive electrode 100 and a negative electrode that serves as both a current collector layer and a negative electrode active material layer. It has a negative electrode 211, a separator 220, an electrolyte 221, and an outer casing 222. By using a negative electrode 211 that serves as both the electrode current collector layer and the negative electrode active material layer, the process is simplified and productivity is increased. It can be made into a high-performance secondary battery. Furthermore, it can be made into a secondary battery with high energy density. ru.

[0089] [Manufacturing method] Next, regarding an example of the flow chart for the manufacturing method of the secondary battery 200 shown in Figures 4A and 4B, see Figure 8. I will use it to explain.

[0090] First, a positive electrode current collector 103 is formed on the substrate 110 (S1). The film deposition method is sputtering. Methods such as vapor deposition can be used. Furthermore, a conductive substrate can be used as a current collector. That's fine too. As for the positive electrode current collector 103, gold, platinum, aluminum, titanium, copper, magnesium Cium, iron, cobalt, nickel, zinc, germanium, indium, silver, palladium, etc. Highly conductive materials such as metals and alloys thereof can be used. Elements that improve heat resistance, such as titanium, neodymium, scandium, and molybdenum, are added. Aluminum can be used. It also reacts with silicon to form silicides. It may be formed from a metallic element that reacts with silicon to form a silicide. For example, zirconium, titanium, hafnium, vanadium, niobium, tantalum, chromium, mo Examples include ribdenum, tungsten, cobalt, and nickel.

[0091] Furthermore, the substrate 110 can be a ceramic substrate, a glass substrate, a resin substrate, a silicon substrate, A metal substrate can be used. If a flexible material is used as the substrate 110, Flexible thin-film secondary batteries can be fabricated.

[0092] The positive electrode current collector 103 combines the functions of both a substrate and a positive electrode current collector by using a highly conductive material. This is possible. In this case, it is preferable to use a metal substrate such as titanium or copper. Furthermore, if a base film 104 is provided, the base film 104 is included in the positive electrode active material layer 101, etc. The oxygen present prevents oxidation of the positive electrode current collector 103, or inhibits the diffusion of metal atoms. Therefore, even if the material is easily oxidized or contains easily diffused metal atoms, the positive electrode current collector 1 It can be applied to 03.

[0093] Next, the undercoat 104 is deposited (S2). The undercoat 104 is deposited using the sputtering method. Vapor deposition methods can be used. For example, when titanium nitride is used as the undercoat 104. This involves depositing titanium nitride using a reactive sputtering method with a titanium target and nitrogen gas. It is possible.

[0094] Next, the positive electrode active material layer 101 is formed (S3). The positive electrode active material layer 101 is, for example, lithium And, the main component is an oxide containing one or more of manganese, cobalt, and nickel. A film can be deposited by sputtering using a sputtering target. Sputtering primarily using lithium cobalt oxide (LiCoO2, LiCo2O4, etc.) Ring targets, mainly lithium manganese oxide (LiMnO2, LiMn2O4, etc.) The sputtering target or lithium nickel oxide (LiNiO2) is used as a component. A sputtering target primarily composed of LiNi2O4 (or similar) can be used. Alternatively, the film may be formed by vacuum deposition.

[0095] Furthermore, in the sputtering method, a metal mask can be used to selectively deposit films. Furthermore, dry etching or wet etching can be performed using a resist mask or the like. The positive electrode active material layer 101 may be patterned by selectively removing certain components.

[0096] Furthermore, to form a positive electrode active material layer 101 having magnesium, fluorine, aluminum, etc. Therefore, in addition to lithium, manganese, cobalt, and nickel, A film is deposited using a sputtering target containing magnesium, fluorine, aluminum, etc. It is also acceptable to use lithium and one or more of manganese, cobalt, and nickel. After forming a film using a sputtering target mainly composed of oxides, magnesium A film of um, fluorine, aluminum, etc., may be formed by vacuum deposition and then annealed.

[0097] Next, a cap layer 102 is formed on the positive electrode active material layer 101 (S4). Cap layer 102 For film formation methods, sputtering and vapor deposition methods can be used. For example, cap When titanium oxide is used as layer 102, the reaction using a titanium target and oxygen gas is performed. Titanium oxide can be deposited using the sputtering method. Furthermore, the titanium oxide target can be... Thin films can also be deposited by sputtering.

[0098] The deposition of the positive electrode active material layer 101 and the cap layer 102 is preferably carried out at a high temperature (500°C or higher). This allows for the production of a positive electrode 100 with better crystallinity.

[0099] Next, a solid electrolyte layer 203 is formed on the positive electrode active material layer 101 (S5).

[0100] It is preferable to use a titanium-containing compound for the solid electrolyte layer 203. The positive electrode 100 has Since the cap layer 102 has titanium, the solid electrolyte layer 203 also has titanium in its material. Using this method, secondary batteries can be easily manufactured. The film deposition method includes sputtering, Vapor deposition methods can be used.

[0101] Next, a negative electrode active material layer 204 is deposited on the solid electrolyte layer 203 (S6). Methods such as sputtering and vapor deposition can be used.

[0102] Next, a negative electrode current collector 205 is fabricated on the negative electrode active material layer 204 (S7). Negative electrode current collector 205 The materials include aluminum, titanium, copper, gold, chromium, tungsten, molybdenum, One or more conductive materials selected from nickel, silver, etc. are used. Sputtering and vapor deposition methods can be used. In addition, in the sputtering method, metal By using a mask, film deposition can be selectively performed. Furthermore, by using a resist mask, etc. The conductive film can be selectively removed by dry etching or wet etching. It's okay to turn things around.

[0103] Furthermore, when the positive electrode current collector 103 or the negative electrode current collector 205 is deposited by sputtering, the positive electrode At least one of the active material layer 101 and the negative electrode active material layer 204 is formed by sputtering. This is preferable. The sputtering apparatus uses the same chamber or multiple chambers for continuous operation. It is also possible to perform film deposition, and the manufacturing equipment can be a multi-chamber type or an in-line type. It can also be made into a device. The sputtering method uses a chamber and a sputtering target. This is a manufacturing method suitable for mass production. Furthermore, the sputtering method allows for thin molding and has unique film deposition characteristics. It has excellent properties.

[0104] Next, a protective layer 206 is formed on the positive electrode 100, the solid electrolyte layer 203, and the negative electrode 210. (S8) is preferable. The protective layer 206 may be hafnium, aluminum, gallium, Yttrium, Zirconium, Tungsten, Titanium, Tantalum, Nickel, Germanium One or more elements selected from luminous, neodymium, lanthanum, or magnesium. The metal oxides contained can be used. Also, silicon nitride or silicon nitride Other methods can also be used. The protective layer 206 can be deposited using the sputtering method.

[0105] Furthermore, each layer described in this embodiment is not particularly limited to the sputtering method, but can also be a vapor phase method (vacuum deposition method). Thermal spraying, pulsed laser deposition (PLD), ion plating, cold spraying The Ray method and aerosol deposition method can also be used. AD (Automated Deposition) is a method of forming a film without heating the substrate. Aerosol refers to gas This refers to fine particles dispersed in a substance. It also refers to methods such as CVD and ALD (Atomic Lightning). The Ayer Deposition method may also be used.

[0106] A secondary battery 200, which is one embodiment of the present invention, can be manufactured through the above process.

[0107] This embodiment can be implemented in appropriate combination with other embodiments.

[0108] (Embodiment 3) To increase the output voltage of a thin-film secondary battery, secondary batteries can be connected in series. While Embodiment 2 showed an example of a secondary battery with one cell, this embodiment shows multiple cells. This example shows how to fabricate a thin-film secondary battery by connecting two components in series.

[0109] Figure 9A shows a top view of the first secondary battery immediately after its formation, and Figure 9B shows the two secondary batteries in series. The connected top view is shown. Note that in Figures 9A and 9B, the figure shown in Embodiment 2 is shown. The same symbols are used for parts identical to 5A.

[0110] Figure 9A shows the state immediately after the negative electrode current collector 205 has been film-formed. Figure 5A is the negative electrode current collector. The top surface shape of 205 is different. The negative electrode current collector 205 shown in Figure 9A has a different side surface of the solid electrolyte layer. It is in partial contact with the insulating surface of the substrate.

[0111] Then, on the region of the negative electrode current collector 205 that does not overlap with the first negative electrode active material layer, the second negative electrode active The material layer, the second solid electrolyte layer 213, the second positive electrode active material layer, and the second positive electrode current collector 215 The layers are formed in this order. Finally, the protective layer 206 is formed (Figure 9B).

[0112] Figure 9B shows a configuration in which two solid-state rechargeable batteries are arranged on a plane and connected in series.

[0113] This embodiment can be implemented in appropriate combination with other embodiments.

[0114] (Embodiment 4) To increase the output voltage of a thin-film secondary battery, or to increase its discharge capacity, the positive electrode and This can be a multilayer secondary battery in which multiple negative electrodes are superimposed and stacked. Embodiment 2 While the above example shows a secondary battery with a single-layer cell, this embodiment shows an example of a thin-film battery with a multi-layer cell. This indicates.

[0115] Figure 10 shows an example of a cross-section of a three-layer thin-film battery. A positive electrode current collector 103 is formed on a substrate 110. The positive electrode current collector 103 is then covered with a base film 104, a positive electrode active material layer 101, a cap layer 102, and a solid base film 104, a positive electrode active material layer 101, and a cap layer 102. By sequentially forming the body electrolyte layer 203, the negative electrode active material layer 204, and the negative electrode current collector 205, It constitutes the second cell.

[0116] Furthermore, a second negative electrode active material layer 204, a solid electrolyte layer, and a cap layer are placed on the negative electrode current collector 205. The second cell is formed by sequentially forming the positive electrode active material layer, the underlayer, and the positive electrode current collector layer. Yes, they are.

[0117] Furthermore, on the second layer of positive electrode current collector, there is a third layer of undercoat film, a positive electrode active material layer, a cap layer, and a solid electrolytic layer. The third cell is formed by sequentially creating the material layer, the negative electrode active material layer, and the negative electrode current collector layer. ru.

[0118] In Figure 10, the protective layer 206 is formed last. The three-layer lamination shown in Figure 10 has a large capacity. Although it is configured to be connected in series for optimal performance, it can also be connected in parallel using external wiring. Yes, it is possible. Furthermore, you can choose between series and parallel connections, or series-parallel, for external wiring.

[0119] Note that the solid electrolyte layer 203, the second solid electrolyte layer, and the third solid electrolyte layer are made of the same material. Using this method is preferable because it can reduce manufacturing costs.

[0120] Furthermore, Figure 11 shows an example of a manufacturing flow for obtaining the structure shown in Figure 10.

[0121] In Figure 11, to reduce the number of manufacturing steps, lithium cobalt oxide is used as the positive electrode active material layer. It is preferable to use a titanium film as the positive electrode current collector and the negative electrode current collector (conductive layer). By using a titanium film as a common electrode, a 3-layer stacked cell can be realized with a minimal configuration. ru.

[0122] This embodiment can be implemented in appropriate combination with other embodiments.

[0123] (Embodiment 5) In this embodiment, the manufacturing process from the positive electrode current collector layer to the negative electrode current collector layer of the secondary battery can be fully automated. An example of a multi-chamber type manufacturing apparatus is shown in Figures 12 and 13. This manufacturing apparatus is the present invention. It can be suitably used for manufacturing a thin film secondary battery according to one aspect.

[0124] FIG. 12 shows an example of a multi-chamber manufacturing apparatus including gates 880, 881, 882, 883, 884, 885, 886, 887, 888, a load lock chamber 870, a mask alignment chamber 891, a first transfer chamber 871, a second transfer chamber 872, a third transfer chamber 873, a plurality of film deposition chambers (a first film deposition chamber 892, a second film deposition chamber 874 ), a heating chamber 893, a second material supply chamber 894, a first material supply chamber 895, a third material supply chamber 896.

[0125] The mask alignment chamber 891 has at least a stage 851 and a substrate transfer mechanism 852.

[0126] The first transfer chamber 871 has a substrate cassette lifting mechanism, and the second transfer chamber 872 has a substrate transfer mechanism 8 53, and the third transfer chamber 873 has a substrate transfer mechanism 854.

[0127] The first film deposition chamber 892, the second film deposition chamber 874, the second material supply chamber 894, the first material supply chamber 89 5, the third material supply chamber 896, the mask alignment chamber 891, the first transfer chamber 871, the second transfer chamber 872, and the third transfer chamber 873 are each connected to an exhaust mechanism. As the exhaust mechanism, an exhaust device may be appropriately selected according to the usage of each chamber. For example, an exhaust mechanism having an adsorption means such as a cryopump, a sputter ion pump, a titanium sublimation pump, etc., or an exhaust mechanism having a cold trap in a turbo molecular pump may be mentioned.

[0128] As a procedure for film deposition on a substrate, the substrate 850 or the substrate cassette is loaded into the load lock chamber 870. ​​Set it up and transport it to the mask alignment chamber 891 by the substrate transport mechanism 852. In the mask alignment chamber 891, pick up the mask to be used from among a plurality of pre-set masks and align it with the substrate on the stage 851. After the alignment is completed, the gate 880 is opened, and the mask and the substrate 850 are transported to the first transport chamber 871 by the substrate transport mechanism 852. After transporting the mask and the substrate 850 to the first transport chamber 871, open the gate 881 and transport them to the second transport chamber 872 by the substrate transport mechanism 853.

[0129] The first film formation chamber 892 provided in the second transport chamber 872 via the gate 882 is a sputtering film formation chamber. The sputtering film formation chamber is a mechanism capable of switching between an RF power source and a pulsed DC power source to apply a voltage to the sputtering target. Also, two or three types of sputtering targets can be set. In this embodiment, a single crystal silicon target, a sputtering target mainly composed of lithium cobalt oxide (LiCoO2), and a titanium target are installed. A substrate heating mechanism is provided in the first film formation chamber 892, and it is also possible to form a film while heating to a heater temperature of 700 °C.

[0130] In the sputtering method using a single crystal silicon target, the negative electrode active material layer can be formed. Also, a film made of SiO can be used as the negative electrode active X material layer by using a reactive sputtering method with Ar gas and O2 gas. It is also possible to use a silicon nitride film as a sealing film by a reactive sputtering method with Ar gas and N2 gas. In the sputtering method using a sputtering target mainly composed of lithium cobalt oxide (LiCoO2), the positive electrode active material layer is formed. ​​​​​​​This is possible. In the sputtering method using a titanium target, a conductive film that acts as a current collector is formed. It is possible to obtain a titanium nitride film by reactive sputtering using Ar gas and N2 gas. It is also possible to form a cap layer or undercoat.

[0131] When forming the positive electrode active material layer, the mask and substrate are stacked and then transported by the substrate transport mechanism 853. Then it is transported from the second transport chamber 872 to the first deposition chamber 892, and the gate 882 is closed, sputtering The film is deposited using the molten metal deposition method. After the film deposition is complete, gates 882 and 883 are opened. The material can be transported to the heating chamber 893, and after closing the gate 883, heating can be performed. Heating chamber 89 For the heat treatment in step 3, an RTA (Rapid Thermal Annealing) device and a resistance heating device are used. A furnace or microwave heating device can be used. The RTA device uses GRTA (Gas Rapid Thermal Anneal) equipment, LRTA (Lamp Rapid A thermal annealing (CNC) apparatus can be used. The heat treatment of heating chamber 893 is This can be carried out under an atmosphere of nitrogen, oxygen, noble gas, or dry air. Also, heating time This should be between 1 minute and 24 hours.

[0132] Then, after the film deposition or heat treatment is completed, the substrate and mask are placed in the mask alignment chamber 89. Return to step 1 and align the new mask. The substrate and mask after alignment are then placed on the base The plate is transported to the first transport chamber 871 by the plate transport mechanism 852. Lifting mechanism of the first transport chamber 871 The substrate is transported by the board, and the gate 884 is opened and the substrate transport mechanism 854 moves into the third transport chamber 87 Transport to 3.

[0133] The second deposition chamber 874, which is connected to the third transport chamber 873 via gate 885, is a deposition chamber where deposition occurs. Form a film.

[0134] An example of the cross-sectional structure of the configuration of the second film-forming chamber 874 is shown in FIG. 13. The cross-sectional schematic diagram cut along the dotted line in FIG. 12 is FIG. 13. The second film-forming chamber 874 is connected to an exhaust mechanism 849, and the first material supply chamber 895 is connected to an exhaust mechanism 848. The second material supply chamber 894 is connected to an exhaust mechanism 847. The second film-forming chamber 874 shown in FIG. 13 is a vapor deposition chamber that performs vapor deposition using a vapor deposition source 856 moved from the first material supply chamber 895, and vapor deposition sources are moved from a plurality of material supply chambers respectively so that a plurality of substances can be vaporized and deposited simultaneously, that is, co-deposited. In FIG. 13, a vapor deposition source having a vapor deposition boat 858 moved from the second material supply chamber 894 is shown.

[0135] Also, the second film-forming chamber 874 is connected to the second material supply chamber 894 via a gate 886. Also, the second film-forming chamber 874 is connected to the first material supply chamber 895 via a gate 888. Also, the second film-forming chamber 874 is connected to the third material supply chamber 896 via a gate 887. Therefore, ternary co-deposition is possible in the second film-forming chamber 874.

[0136] As a procedure for performing vapor deposition, first, a substrate is placed on a substrate holding portion 845. The substrate holding portion 845 is connected to a rotation mechanism 865. Then, in the first material supply chamber 895, the first vapor deposition material 855 is heated to a certain extent, and when the vapor deposition rate becomes stable, the gate 888 is opened, and the arm 86 2 is extended to move the vapor deposition source 856 and stop it at a position below the substrate. The vapor deposition source 856 is composed of the first vapor deposition material 855, a heater 857, a container for storing the first vapor deposition material 855, It is composed of the following. In addition, the second material supply chamber 894 also adds the second deposition material to some extent. Once heated and the deposition rate stabilized, the gate 886 was opened and the arm 861 was extended to create the deposition source. Move it and stop it at the lower position of the circuit board.

[0137] Subsequently, the shutter 868 and the deposition source shutter 869 are opened to perform co-deposition. During this process, the rotating mechanism 865 is rotated to improve the uniformity of the film thickness. The substrate after deposition is then processed along the same path. It follows this path and is transported to mask alignment room 891. When removing a substrate from the manufacturing equipment. It will be transported from the mask alignment room 891 to the load lock room 870 for removal. ru.

[0138] Furthermore, in Figure 13, when the substrate 850 and the mask are held in the substrate holding part 845, As an example, the substrate 850 (and mask) is rotated by the substrate rotation mechanism, This can improve uniformity. The substrate rotation mechanism may also serve as the substrate transport mechanism.

[0139] Furthermore, the second film deposition chamber 874 may also be equipped with imaging means 863 such as a CCD camera. By including the image means 863, the position of the substrate 850 can be confirmed.

[0140] Furthermore, in the second film deposition chamber 874, the film deposition on the substrate surface is determined based on the measurement results of the film thickness measurement mechanism 867. The film thickness can be predicted. The film thickness measurement mechanism 867 includes, for example, a quartz crystal oscillator. That would be good.

[0141] Furthermore, in order to control the deposition of the vaporized deposition material, the base will be used until the vaporization rate of the deposition material stabilizes. The shutter 868 overlaps with the plate, and the deposition source shutter overlaps with the deposition source 856 and the deposition boat 858. It is equipped with TA869.

[0142] In the deposition source 856, an example of a resistance heating method is shown, but EB (Electron B A vapor deposition (eam) method may also be used. Furthermore, an example of a crucible is shown as the container for the vapor deposition source 856. However, a vapor deposition boat may also be used. The crucible heated by heater 857 contains the first vapor deposition material. Organic materials are added as 855. Also, pellets or particulate SiO are used as deposition materials. When used, the vapor deposition boat 858 is used. The vapor deposition boat 858 consists of three parts. A member with a concave surface, an inner lid with two holes, and an outer lid with one hole are stacked on top of each other. The inner lid may be removed before performing the vapor deposition. The vapor deposition boat 858 is powered by... It acts as a resistor, causing the deposition boat itself to heat up.

[0143] Furthermore, although this embodiment shows an example of a multi-chamber system, it is not particularly limited to inlays. It may also be used as a manufacturing apparatus for the N-type system.

[0144] This embodiment can be implemented in appropriate combination with other embodiments.

[0145] (Embodiment 6) This embodiment describes an example of a thin-film secondary battery having a battery control circuit and the like.

[0146] Figure 14A is an external view of the thin-film secondary battery. The secondary battery 913 has terminals 951 and 9 It has terminal 52. Terminal 951 is electrically connected to the positive terminal, and terminal 952 is electrically connected to the negative terminal. A secondary battery according to one embodiment of the present invention has excellent cycle characteristics. Furthermore, it is an all-solid-state secondary battery. Therefore, it is also safe. Thus, a secondary battery according to one aspect of the present invention is a secondary battery 9 It can be suitably used as 13.

[0147] Figure 14B is an external view of the battery control circuit. The battery control circuit shown in Figure 14B is on circuit board 900 and has layer 916. Circuit 912 and antenna 914 are provided on substrate 900. Antenna 914 is electrically connected to circuit 912. Circuit 912 has terminals 971 and Terminal 972 is electrically connected. Circuit 912 is electrically connected to terminal 911.

[0148] Terminal 911 is connected to a device that is powered by, for example, a thin-film solid-state rechargeable battery. It is then connected to a display device, sensor, etc.

[0149] Layer 916 has the function of shielding electromagnetic fields, for example, from the secondary battery 913. For layer 916, for example, a magnetic material can be used.

[0150] Figure 14C shows an example where the battery control circuit shown in Figure 14B is placed on the secondary battery 913. Sub-terminal 971 is electrically connected to terminal 951, and terminal 972 is electrically connected to terminal 952. 916 is positioned between the circuit board 900 and the secondary battery 913.

[0151] It is preferable to use a flexible substrate as the substrate 900.

[0152] By using a flexible substrate as substrate 900, a thin battery control circuit can be realized. This is possible. Also, as shown in Figure 15D later, the battery control circuit is wrapped around the secondary battery. It is possible.

[0153] Using Figures 15A to 15D, another example of a thin-film secondary battery having a battery control circuit etc. Let me explain. Figure 15A is an external view of a thin-film type solid secondary battery. Figure 15B shows the battery control The circuit has a substrate 900 and a layer 916.

[0154] As shown in Figure 15C, the substrate 900 is bent to match the shape of the secondary battery 913, and the battery control cycle By arranging the circuit around the secondary battery, the battery control circuit is configured as shown in Figure 15D. It can be wrapped around a battery. By using a secondary battery with this configuration, a smaller battery can be made. It can be used as a secondary battery.

[0155] This embodiment can be implemented in appropriate combination with other embodiments.

[0156] (Embodiment 7) In this embodiment, an example of an electronic device using a thin-film secondary battery is shown in Figures 16A, 16B and This will be explained using Figures 17A to 17C. One embodiment of the present invention is a secondary battery with discharge capacity and It has high performance characteristics and high safety. Therefore, this electronic device is highly safe and can be used for extended periods. That is the case.

[0157] Figure 16A is an external perspective view of the thin-film secondary battery 3001 according to the present invention. A positive lead electrode 513 electrically connected to the positive electrode, and a negative lead electrode electrically connected to the negative electrode. The electrode 511 is sealed with a laminate film or insulating material so that it protrudes.

[0158] Figure 16B shows an IC card, which is an example of an application device using the thin-film secondary battery according to the present invention. The power obtained from the radio wave 3005 is used to charge the thin-film secondary battery 3001. This is possible. Inside the IC card 3000 are an antenna and IC3004, and a thin-film secondary battery. 3001 is positioned. On IC card 3000 is the worker wearing the management badge. ID3002 and photo3003 are displayed. The thin-film secondary battery 3001 has been charged. It is also possible to use force to transmit signals such as authentication signals from the antenna.

[0159] An active matrix display device is provided for the display of ID3002 and photograph 3003. It may also be an active matrix display device such as a reflective liquid crystal display device or an organic EL display device. Examples include digital displays and electronic paper. Active matrix display devices display video (moving or still images). It can also display ) and time. The power consumption of the active matrix display device is equivalent to that of a thin-film type 2 Next, power can be supplied from battery 3001.

[0160] Since IC cards use plastic substrates, organic EL displays using flexible substrates are available. A display device is preferred.

[0161] Alternatively, a solar cell may be installed instead of the one shown in photograph 3003. It absorbs light from ambient light and generates electricity. It can generate power and use that power to charge the thin-film secondary battery 3001.

[0162] Furthermore, thin-film rechargeable batteries are not limited to IC cards, but are also used to power wireless sensors used in vehicles. It can be used as a power source, a secondary battery for MEMS devices, and the like.

[0163] Figure 17A shows an example of a wearable device. A wearable device has a power source and In some cases, rechargeable batteries may be used. Also, when the user uses it in daily life or outdoors... Therefore, in order to enhance splash resistance, water resistance, or dust resistance, the connector part that connects is exposed. Wearable devices that can be charged wirelessly, in addition to wired charging, are desired. .

[0164] For example, a secondary battery according to one aspect of the present invention is provided in a spectacle-type device 400 as shown in Figure 17A. It can be mounted. The glasses-type device 400 consists of a frame 400a and a display unit 400b It has a secondary battery mounted in the temple portion of the curved frame 400a, making it lightweight. The goal is to create a glasses-type device 400 that is both lightweight and has a good weight balance, allowing for extended use. This is possible. By incorporating a secondary battery, which is one aspect of the present invention, the casing can be miniaturized and space can be saved. This allows for a configuration that can accommodate systemization.

[0165] Furthermore, the headset-type device 401 is equipped with a secondary battery according to one aspect of the present invention. Yes, it is possible. The headset-type device 401 includes at least a microphone unit 401a and a flexible It has a flexible pipe 401b and an earphone section 401c. A secondary battery can be provided inside the earphone section 401c. By incorporating a pond, it is possible to achieve a configuration that can accommodate space savings due to the miniaturization of the enclosure. can.

[0166] Furthermore, a secondary battery according to one aspect of the present invention is mounted on a device 402 that can be directly attached to the body. This is possible. A secondary battery 402b is provided inside the thin housing 402a of the device 402. This can be achieved. By incorporating a secondary battery, which is one aspect of the present invention, the housing can be made smaller. This allows for a configuration that can accommodate space-saving requirements.

[0167] Furthermore, a secondary battery according to one aspect of the present invention is mounted on a device 403 that can be attached to clothing. This is possible. A secondary battery 403b is provided inside the thin housing 403a of the device 403. This is possible. By incorporating a secondary battery, which is one aspect of the present invention, the housing can be miniaturized and energy-saving. This allows for a configuration that can handle pacing.

[0168] Furthermore, a secondary battery according to one aspect of the present invention can be mounted on the belt-type device 406. The belt-type device 406 comprises a belt portion 406a and a wireless power supply / receiving portion 406b. The belt portion 406a can be used to house a secondary battery. In one aspect of the present invention By incorporating a certain type of rechargeable battery, a configuration that can accommodate space savings due to the miniaturization of the casing has been achieved. It is possible.

[0169] Furthermore, a secondary battery according to one aspect of the present invention can be mounted in the wristwatch-type device 405. The wristwatch-type device 405 has a display unit 405a and a belt unit 405b, and the display unit 40 A secondary battery can be provided in 5a or the belt portion 405b. This is one aspect of the present invention. By incorporating a secondary battery, a configuration that allows for space saving due to the miniaturization of the casing can be achieved. It is possible.

[0170] The display unit 405a can display not only the time, but also various other information such as incoming emails and phone calls. It is possible.

[0171] Furthermore, the wristwatch-type device 405 is a wearable device that is worn directly on the wrist. Therefore, it may be equipped with sensors to measure the user's pulse, blood pressure, etc. It can also accumulate health-related data and manage one's health.

[0172] Figure 17B shows a perspective view of the wristwatch-type device 405 after it has been removed from the arm.

[0173] Figure 17C also shows a side view of the wristwatch-type device 405. Figure 17C shows the secondary battery inside. This shows the built-in battery 913. The secondary battery 913 is the secondary battery shown in Embodiment 5. It is a battery. The secondary battery 913 is located in a position that overlaps with the display unit 405a, and is small and It's lightweight.

[0174] This embodiment can be implemented in appropriate combination with other embodiments.

[0175] (Embodiment 8) In this embodiment, regarding an electronic device using a secondary battery having a positive electrode according to one aspect of the present invention, This will be explained using Figures 18A to 18C, Figures 19A to 19D, and Figures 20A and 20B. To clarify, a secondary battery having a positive electrode according to one aspect of the present invention has high discharge capacity and cycle characteristics. It is highly safe. Therefore, it can be suitably used in electronic devices such as those listed below. In particular, it is highly resistant It can be suitably used in electronic devices where durability is required.

[0176] Figure 18A shows a perspective view of the 700 wristwatch-type personal information terminal (also called a smartwatch). The personal digital assistant 700 consists of a casing 701, a display panel 702, a clasp 703, and a band 70 It has 5A, 705B, and operation buttons 711 and 712.

[0177] The display panel 702 mounted on the housing 701, which also serves as the bezel, has a rectangular display area. Furthermore, the display area has a curved surface. The display panel 702 is flexible. This is preferable. The display area may not be rectangular.

[0178] Bands 705A and 705B are connected to the housing 701. The fastener 703 is It is connected to band 705A. Band 705A and housing 701 are connected, for example, via pins. The part is connected so that it can rotate. Band 705B and housing 701, and band 705 The same applies to the connection between A and clasp 703.

[0179] Figures 18B and 18C show perspective views of band 705A and secondary battery 750, respectively. Band 705A has a secondary battery 750. The secondary battery 750 is, for example, the one described above. The secondary battery described above can be used. The secondary battery 750 is embedded inside the band 705A. The positive lead 751 and negative lead 752 are embedded, and a portion of each is in band 705A. It protrudes (see Figure 18B). The positive lead 751 and the negative lead 752 are indicators It is electrically connected to the Nel 702. The surface of the secondary battery 750 is covered by the outer casing 753. (See Figure 18C). Note that the above pins may also function as electrodes. Specifically, , positive lead 751 and display panel 702, and negative lead 752 and display panel The 702 is electrically connected to the band 705A and the housing 701 via the pins that connect them. It may be connected. In this way, the connection between band 705A and housing 701 The configuration can be simplified.

[0180] The secondary battery 750 is flexible. Therefore, the band 705A is integrated with the secondary battery 750. It can be manufactured by making a mold that corresponds to the outer shape of band 705A and a secondary battery 75 Set to 0, pour the material for band 705A into the mold, and cure the material as shown in the figure. The band 705A shown in 18B can be fabricated.

[0181] When using rubber material as the material for band 705A, the rubber is hardened by heat treatment. For example, when using fluororubber as a rubber material, a heat treatment at 170°C for 10 minutes is performed. Curing. Also, if silicone rubber is used as the rubber material, curing at 150°C for 10 minutes. It is hardened by heat treatment.

[0182] Materials used for Band 705A include fluororubber, silicone rubber, and fluorosilicone. Examples include cone rubber and urethane rubber.

[0183] Furthermore, the portable information terminal 700 shown in Figure 18A can have various functions. For example, , a function to display various information (still images, videos, text images, etc.) in the display area, touch panel Features such as a calendar, date or time display, and various software (programs) A function that controls processing by RAM, wireless communication function, and various computers using wireless communication function Features include connecting to a network and transmitting or receiving various types of data using wireless communication. A function that reads programs or data recorded on a recording medium and displays them in the display area. It may have functions such as demonstrating [the above].

[0184] Furthermore, inside the housing 701 are a speaker and sensors (force, displacement, position, velocity, acceleration, angular velocity). Rotation speed, distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, current, voltage , including functions for measuring power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation. ), it may have a microphone, etc. The portable information terminal 700 has a light-emitting element It can be manufactured by using it in the display panel 702.

[0185] Note that Figure 18A shows an example where secondary battery 750 is included in band 705A, but secondary battery 750 may be included in band 705B. Band 705B is band 705A. Similar materials can be used.

[0186] Figure 19A shows an example of a cleaning robot. The cleaning robot 6300 has a housing 6301 A display unit 6302 is located on the top surface, multiple cameras 6303 are located on the side, and a brush 6 It has 304, operation buttons 6305, various sensors, etc. Although not shown, a cleaning robot The 6300 is equipped with wheels, a suction port, etc. The 6300 cleaning robot is self It moves, detects dust 6310, and sucks up the dust from the suction port located on the bottom. Cut.

[0187] For example, the cleaning robot 6300 analyzes images captured by the camera 6303 to identify walls, furniture, etc. It can also determine the presence or absence of obstacles such as steps. Furthermore, image analysis can detect wiring, etc. If an object that may become entangled in the brush 6304 is detected, the rotation of the brush 6304 will be stopped. This is possible. The cleaning robot 6300 has a secondary battery according to one aspect of the present invention inside it, and a semi-automatic battery. A conductor device or electronic component is provided. A secondary battery according to one aspect of the present invention is used in a cleaning robot 630. By using 0, the cleaning robot 6300 becomes a reliable electronic device with a long operating time. It is possible.

[0188] Figure 19B shows an example of a robot. The robot 6400 shown in Figure 19B is a secondary power Pond 6409, Illuminance sensor 6401, Microphone 6402, Top camera 6403, Speaker -Camera 6404, display unit 6405, lower camera 6406 and obstacle sensor 6407, movement It is equipped with mechanism 6408, a computing device, and the like.

[0189] Microphone 6402 has the function of detecting the user's voice and ambient sounds, etc. Speaker 6404 has the function of emitting sound. Robot 6400 has a microphone Using the 6402 and speaker 6404, communication with the user is possible. It is possible.

[0190] The display unit 6405 has the function of displaying various information. The robot 6400 is used by The desired information can be displayed on the display unit 6405. The display unit 6405 is touch It may also be equipped with a panel. Furthermore, the display unit 6405 is a detachable information terminal. It is also possible to install it in a fixed position on the robot 6400 for charging and data transfer. Make it possible.

[0191] The upper camera 6403 and lower camera 6406 are used to image the area around the robot 6400. It has the ability to move the robot 6407 using the moving mechanism 6408. Robot 64 can detect the presence or absence of obstacles in the direction of travel as it moves forward. 00 uses the upper camera 6403, the lower camera 6406, and the obstacle sensor 6407 It can perceive its surroundings and move safely.

[0192] The robot 6400 contains a secondary battery 6409 according to one aspect of the present invention and a semiconductor device inside it. or equipped with electronic components. A secondary battery according to one aspect of the present invention is used in the robot 6400. This allows the robot 6400 to be a highly reliable electronic device with a long operating time.

[0193] Figure 19C shows an example of an aircraft. The aircraft 6500 shown in Figure 19C has a propeller 6 It has components such as the 501, camera 6502, and secondary battery 6503, and is capable of autonomous flight. To possess.

[0194] For example, image data captured by camera 6502 is stored in electronic component 6504. Component 6504 analyzes image data to detect the presence or absence of obstacles during movement. Yes, it is possible. Also, the electronic component 6504 changes the storage capacity of the secondary battery 6503, and the battery The remaining amount of territory can be estimated. The aircraft 6500 has inside it one aspect of the present invention The invention includes a secondary battery 6503. A secondary battery according to one aspect of the present invention is used in the aircraft 6500. This allows the aircraft 6500 to have long operating time and reliable electronic equipment.

[0195] Figure 19D shows an example of an automobile. Automobile 7160 is a secondary battery 7161, engine It has a hub, tires, brakes, steering system, camera, etc. Furthermore, the system 1000 described later... It is preferable that it has a secondary battery according to one aspect of the present invention. The automobile 7160 has a secondary battery according to one aspect of the present invention inside it. It is equipped with 7161. By using a secondary battery according to one aspect of the present invention in an automobile 7160, The 7160 motor vehicle can be made into a vehicle with a long driving range, high safety, and high reliability. .

[0196] Furthermore, one aspect of the present invention comprises the thin-film battery described in the previous embodiment and another secondary battery. It may be an electronic device or system. Other secondary batteries are not particularly limited, but even A lithium-ion secondary battery having a positive electrode, a negative electrode, an electrolyte, and a separator, or A solid-state rechargeable battery can be used. Note that in this specification, "system" refers to individual units. This refers to a system formed by combining the following elements. One of these elements is a secondary battery.

[0197] Figure 20A shows the thin-film battery 1001 described in the previous embodiment, the positive electrode, the negative electrode, and the electrolyte. The system 1000 has a lithium-ion secondary battery 1002 having a separator. By using such electronic devices or systems, a secondary discharge capacity with greater capacity can be achieved. This combines the advantages of both a battery and the thin-film battery described in the previous embodiment, which is easy to make thin and light. It is possible to do so. System 1000 preferably has a wireless power supply device. With a wireless power supply device, the lithium-ion secondary battery 1002 is used to power the thin-film battery 1001 It can be easily powered.

[0198] Figure 20B shows the interior of automobile 7160 when it has system 1000. Unit 60 has a secondary battery for driving, a wireless power supply device 7162, and a key 7163. By placing the key 7163 on the wireless power supply device 7162, the secondary battery 7161 for driving is provided. Power can be supplied to the key 7163 from there. Note that in Figure 20B, the wireless power supply device 7162 The example shown is one where it is installed on the dashboard, but this is not the only example. Even if a storage place for the key 7163 is provided and a wireless power supply device 7162 is provided in the storage place, good.

[0199] In this case, if the key 7163 has the thin-film battery described in the previous embodiment, a thinner and lighter key is achieved. It is preferable that this be possible. Also, the secondary battery for driving the automobile 7160 has, for example, a positive electrode and A lithium-ion secondary battery having a negative electrode, an electrolyte, and a separator, or a bulk solid lithium-ion battery. It is preferable to use a secondary battery that can easily obtain a larger discharge capacity, such as a 2D secondary battery.

[0200] This embodiment can be implemented in appropriate combination with other embodiments.

[0201] (Embodiment 9) The device described in this embodiment includes a biosensor and a solid power supply for the biosensor. It has at least one secondary battery, and acquires various biological information using infrared and visible light, and has memory. This biometric information can be stored in the user's personal identification and for health purposes. It can be used for both square applications. A secondary battery according to one aspect of the present invention has a discharge capacity and It has high cycling properties and high safety. Therefore, this device is highly safe and can be used for extended periods. It is usable.

[0202] Biosensors are sensors that acquire biological information and can be used in healthcare applications. The system acquires biometric information such as pulse wave, blood glucose level, oxygen saturation, and triglyceride concentration. These are some examples. The data is stored in memory.

[0203] Furthermore, the device described in this embodiment may be provided with means for acquiring other biological information. It is preferable. For example, in addition to internal biological information such as electrocardiogram, blood pressure, and body temperature, facial expression, complexion, and pupils. This includes superficial biometric information such as the number of steps taken, exercise intensity, elevation changes during travel, and diet (intake). Information such as calories and nutrients is also important for healthcare. By using this, comprehensive health management becomes possible, not only for daily health management but also for treating illnesses and injuries. This can lead to early detection.

[0204] For example, blood pressure is measured by the timing difference between the two heartbeats in the electrocardiogram and the pulse wave (the length of pulse wave propagation time). It can be calculated from the following. When blood pressure is high, the pulse wave propagation time is short, and conversely, when blood pressure is low, the pulse wave The propagation time becomes longer. Also, from the relationship between heart rate and blood pressure calculated from the electrocardiogram and pulse wave, It is also possible to estimate the user's physical condition. For example, if both heart rate and blood pressure are high, it indicates tension. If both heart rate and blood pressure are low, it can be estimated that the person is in an excited state, while if both heart rate and blood pressure are low, it can be estimated that the person is in a relaxed state. It can be estimated that this is the case. Also, if a state of low blood pressure and high heart rate persists, This could indicate a heart condition or other underlying health issue.

[0205] Users use biometric information measured by electronic devices and their own body information estimated based on that information. Being able to check the situation at any time improves health awareness. As a result, people avoid overeating and excessive drinking, and take appropriate measures. Reviewing daily habits, such as being mindful of excessive exercise or managing one's physical condition, This could also serve as an opportunity to seek medical attention from a healthcare provider if necessary.

[0206] Each data point may be shared among multiple biosensors. Figure 21A shows the user Examples of implanting the biosensor 80a inside the body and attaching the biosensor 80b to the wrist. Figure 21A shows a device having a biosensor 80a capable of measuring, for example, an electrocardiogram. The biosensor 80b, which can perform heart rate measurement by optically monitoring the pulse in the user's arm, It is a device that possesses this feature. Note that the watch and wristband type wearable devices shown in Figure 21A The chair is not limited to heart rate measurement; it can use a variety of biosensors.

[0207] In the case of the implantable type device shown in Figure 21A, it is small and generates almost no heat. The prerequisites include that it does not cause allergic reactions or other adverse reactions upon contact with the skin. The secondary battery used in a device according to one embodiment of the present invention is small, generates almost no heat, and It is preferable because no energy reactions occur. Also, embedded devices are wireless charging It is preferable to incorporate an antenna in order to enable power supply.

[0208] The implantable device shown in Figure 21A is a biosensor capable of measuring electrocardiograms. It is not limited to this, and other biosensors capable of acquiring biological data can be used.

[0209] The biosensor 80b built into the device stores the acquired data within the device. It may also have a function to store the data in temporary memory. Alternatively, it may be acquired by a biosensor. Each of the generated data is sent wirelessly or via wired connection to the mobile data terminal 85 in Figure 21B. The mobile data terminal 85 may have a function to detect waveforms. These are devices such as smartphones, and data acquired from each biosensor can be used to identify problems such as arrhythmias. It can detect whether or not this is occurring. The mobile data terminal 85 has multiple biosensors. When sending data acquired via a wired connection, the data acquired before connecting via wired connection should be collected together. Transferring is preferable. Note that each detected data is automatically assigned a date. The data is stored in the memory of the mobile data terminal 85 and can be managed personally. Alternatively, see Figure 21. As shown in B, Network (Internet) The data may be transmitted to hospitals and other medical institutions 87 via (including). The data is the hospital's data It is managed by a data server and can be used as test data during treatment. Medical data is vast. Because it may be large, the biosensor 80b to the mobile data terminal 85 uses Bluetooth. Bluetooth (registered trademark) and networks including the frequency band from 2.4GHz to 2.4835GHz Using a 5th generation wireless system, from mobile data terminal 85 to mobile data terminal 85 High-speed communication may be performed. The 5th generation wireless system uses the 3.7GHz band, 4.5GHz band, and 2 It uses the 8GHz frequency band. By using the 5th generation wireless system, it can be used not only at home but also when out and about. In this case, it is also possible to acquire data and transmit data to 87 medical institutions, and the user's health This allows for accurate acquisition of data during abnormal situations, which can then be used to inform subsequent processing or treatment. The configuration shown in Figure 21C can be used as the mobile data terminal 85.

[0210] Figure 21C shows another example of a portable data terminal. The portable data terminal 89 is a secondary battery In addition, it has a speaker, a pair of electrodes 83, a camera 84, and a microphone 86.

[0211] A pair of electrodes 83 are provided in a part of the housing 82, with the display unit 81a in between. 1b is a region with a curved surface. Electrode 83 is an electrode for acquiring biological information. It works.

[0212] As shown in Figure 21C, by arranging the pair of electrodes 83 in the longitudinal direction of the housing 82, a horizontally elongated shape is formed. When using the mobile data terminal 89 on the screen, biometric information can be acquired without the user's awareness. It can be executed.

[0213] This shows an example of the usage status of the portable data terminal 89. The display unit 81a has a pair of electrodes 83. The acquired electrocardiogram information (88a) and heart rate information (88b) can be displayed.

[0214] If the biosensor 80a is implanted in the user's body as shown in Figure 21A, this function will Although it can be said that it is unnecessary, if it is not implanted, the user will grasp the pair of electrodes 83 with both hands. This allows for the acquisition of an electrocardiogram. A biosensor 80a is implanted in the user's body. Even in crowded conditions, to verify whether the biosensor 80a is functioning correctly The portable data terminal 89 shown in Figure 21C can be used. Furthermore, electrocardiograms can be shared among multiple users. When comparing data, the portable data terminal 89 shown in Figure 21C can also be used.

[0215] Camera 84 can capture images of the user's face, etc. From the image of the user's face, It can acquire biometric information such as emotions, pupil size, and complexion.

[0216] The Mike86 can capture the user's voice. Voiceprint authentication is performed using the acquired voice information. It is possible to obtain voiceprint information that can be used for this purpose. In addition, voice information can be acquired periodically. Furthermore, by monitoring the changes in voice quality, it can also be used for health management. Of course Using microphone 86, camera 84, and speaker, a video call is made to a doctor at medical facility 87. It is possible to talk.

[0217] By using the device shown in Figure 21A and the portable data terminal 89 shown in Figure 21C, remote locations can be accessed. A telemedicine support system that sends information from a patient to a doctor at a hospital and allows the patient to receive medical treatment from the doctor. It can be achieved.

[0218] This embodiment can be implemented in appropriate combination with other embodiments. [Examples]

[0219] In this example, a secondary battery having a base film and a cap layer according to one aspect of the present invention is compared with a secondary battery having a base film and a cap layer according to one aspect of the present invention. As an example, a secondary battery without a base film or cap layer was fabricated, and its charge / discharge characteristics and cycles were examined. We evaluated the characteristics.

[0220] <Manufacturing of secondary batteries> Sample 1, representing one aspect of the present invention, was prepared as follows. First, the substrate and the positive electrode current collector layer. A titanium sheet was used to serve both purposes. The titanium sheet is a rolled foil with a thickness of 0.1 mm. We used 12mm diameter material that was etched and had a non-mirror finish, with a purity of 99.5%.

[0221] Titanium nitride (TiN) is deposited as an undercoat on a titanium sheet using a 20nm sputtering method. The sputtering conditions were as follows. Target: Titanium target, 100mm in diameter Sputtering power supply, output: DC power supply, 500W Atmosphere: Argon flow rate 12.0 sccm, nitrogen flow rate 28 sccm, pressure 0.4 Pa Deposition time: 8 minutes Film deposition temperature: Set to 600°C Deposition rate: 2.5 nm / min

[0222] Next, lithium cobalt oxide (LiCoO2) is used as the positive electrode active material layer by sputtering. A 00nm film was deposited. The sputtering conditions were as follows. Target: Lithium cobalt oxide target, 100mm in diameter Sputtering power supply, output: RF power supply, 500W Atmosphere: Argon flow rate 40 sccm, oxygen flow rate 10 sccm, pressure 0.4 Pa Deposition time: 461 minutes Film deposition temperature: Set to 600°C Deposition rate: 2.2 nm / min

[0223] Next, as the cap layer, titanium oxide (TiO x) was deposited as a film of approximately 20 nm using the sputtering method. The sputtering conditions were as follows: Target: Titanium target, 100mm in diameter Sputtering power supply, output: DC power supply, 500W Atmosphere: Argon flow rate 24 sccm, oxygen flow rate 16 sccm, pressure 0.4 Pa Deposition time: 27.7 minutes Film deposition temperature: Set to 600°C (actual substrate temperature is approximately 400°C) Deposition rate: 0.72 nm / min

[0224] Also, Sample 2, which does not have a base film, and titanium dioxide (TiO2) as the base film. x ) to form a film Sample 3 was prepared. These were prepared in the same way as Sample 1, except for the undercoat.

[0225] Furthermore, as comparative examples, samples 4 to 6 without a cap layer were prepared. The samples were prepared in the same manner as samples 1 to 3, except that a cap layer was not deposited.

[0226] The preparation conditions for each sample are shown in Table 2.

[0227] [Table 2]

[0228] <Battery cell fabrication> Next, using each sample as the positive electrode, a CR2032 type (20mm diameter, 3.2mm height) was used. A coin-shaped battery cell (m) was fabricated.

[0229] Lithium metal was used for the counter electrode.

[0230] The electrolyte in the electrolyte solution is 1 mol / L lithium hexafluoride phosphate (LiPF6). The electrolyte contains ethylene carbonate (EC) and diethyl carbonate (DEC). A mixture with C:DEC = 3:7 (volume ratio) was used. The charge / discharge efficiency was evaluated as follows: For the secondary batteries used, 2 wt% vinylene carbonate (VC) was added to the electrolyte. .

[0231] A 25 μm thick polypropylene was used for the separator.

[0232] The positive electrode and negative electrode cans were made of stainless steel (SUS).

[0233] <Measurement of charge / discharge efficiency> Initial characteristics were measured by charging at CCCV, 0.2C, 4.2V, and a cutoff current of 0.1C. The discharge was performed using CC, 0.2C, and a cutoff voltage of 2.5V. Note that 1C here is correct. The current value per unit weight of the extremely active material was set to 137 mA / g. The measurement temperature was 25°C. Initial characteristics The results of the sex measurement are shown in Table 3 and Figures 22A and 22B. Figure 22A shows Sample 1 to Sample 3, Figure 22B, is a graph of Samples 4 through 6.

[0234] [Table 3]

[0235] Table 3, Figures 22A and 22B show that all samples exhibit good charge-discharge characteristics. I understand.

[0236] <Charge-discharge cycle characteristics> Next, the charge-discharge cycle characteristics of these battery cells were evaluated. The charge and discharge cycles were performed in the same manner as the initial characteristics measurements. The cycle characteristics were shown in Figure 23A and Figure 23A. This is shown in Figure 23B. Figure 23A shows samples 1 to 3, and Figure 23B shows samples 4 to 3. This is the graph for Ru6.

[0237] From Figures 23A and 23B, Samples 1 to 3, which have a cap layer, It showed significantly better cycle characteristics than samples 4 to 6, which did not have a layer. Sample 1, which had titanium nitride as the ground film, showed the best properties after 25 cycles. The discharge capacity was 115 mAh / g, and the discharge capacity retention rate was 93%. A nitrile oxide film was used as the undercoat. Sample 3, which has a tan, showed characteristics second only to Sample 1, and the discharge capacity after 25 cycles. The discharge capacity was 113 mAh / g, and the discharge capacity retention rate was 93%. Sample 2, which did not have a base film, After 25 cycles, the discharge capacity was 111 mAh / g, and the discharge capacity retention rate was 92%. .

[0238] Therefore, by providing a cap layer, it is possible to manufacture a secondary battery with good charge-discharge cycle characteristics. It became clear that charging and discharging were more effective with a base film than without. It was found that the cycle characteristics were good, and titanium nitride was particularly preferred. [Examples]

[0239] In this example, a secondary battery having a cap layer according to one aspect of the present invention is provided, and as a comparative example, a cap layer A secondary battery without a top layer was fabricated, and TEM, electron energy loss spectroscopy (EELS), The characteristics were analyzed using micro-electron diffraction, impedance measurements, etc., and the cycle characteristics were evaluated.

[0240] <Manufacturing of secondary batteries> Sample 11, representing one aspect of the present invention, was prepared as follows. First, the substrate and the positive electrode current collector A 100 μm titanium sheet was used to serve as a layer.

[0241] Titanium nitride (TiN) is deposited as an undercoat on a titanium sheet using a 20nm sputtering method. The sputtering conditions were as follows. Target: Titanium target, 2 inches in diameter Sputtering power supply, output: RF power supply, 100W Atmosphere: Argon flow rate 3.0 sccm, nitrogen flow rate 7 sccm, pressure 0.5 Pa Deposition time: 15 minutes Film deposition temperature: Set to 600°C Target-to-substrate distance: 75mm

[0242] Next, lithium cobalt oxide (LiCoO2) is used as the positive electrode active material layer by sputtering at 90°C. A 0nm film was deposited. The sputtering conditions were as follows. Target: Lithium cobalt oxide target, 2 inches in diameter Sputtering power supply, output: RF power supply, 200W Atmosphere: Argon flow rate 10 sccm, pressure 0.5 Pa Deposition time: 109 minutes Film deposition temperature: Set to 600°C Target-to-substrate distance: 75mm Deposition rate: 9.2 nm / min

[0243] Next, a 20nm layer of titanium dioxide (TiO2) was deposited as a capping layer using the sputtering method. The sputtering conditions were as follows: Target: Titanium target, 100mm in diameter Sputtering power supply, output: DC power supply, 500W Atmosphere: Argon flow rate 24 sccm, oxygen flow rate 16 sccm, pressure 0.4 Pa Deposition time: 27.7 minutes Film deposition temperature: Set to 600°C (actual substrate temperature is approximately 400°C) Deposition rate: 0.72 nm / min

[0244] As a comparative example, sample 12 without a cap layer was prepared. Aside from the P layer, the sample was prepared in the same way as Sample 11.

[0245] The preparation conditions for each sample are shown in Table 4.

[0246] [Table 4]

[0247] <tem> The conditions for capturing TEM images were as follows: Sample preparation: Thinning by FIB method (μ-sampling method) Transmission electron microscope: JEOL JEM-ARM200F Observation conditions: Acceleration voltage: 200kV Magnification accuracy: ±3%

[0248] Figure 24 shows a cross-sectional TEM image of sample 11 before charging and discharging. A titanium oxide cap is present on the surface. Layer 1102 was observed. Figure 27 shows a cross-sectional TEM image of sample 11 after charging and discharging. Surface layer A titanium oxide cap layer 1102 was observed in the part. Figure 30 shows the results of sample 12 after charging and discharging. Cross-sectional TEM images are shown. In all samples, the positive electrode active material layer 1101 of lithium cobalt oxide is shown. It was observed that the material was polycrystalline, and that the crystallites were vertically elongated columnar in shape.

[0249] <eels> Next, the electronic state of cobalt in the sample after charging and discharging was analyzed using EELS, and non-specific The valence was calculated from the L3 / L2 ratio by referring to authorized reference 1. The measurement conditions for EELS are as follows: That's what I decided. Elemental analysis (point analysis) Scanning transmission electron microscope: JEOL JEM-ARM200F Acceleration voltage: 200kV Beam diameter: Approximately 0.1 nm Elemental analyzer: Gatan Quantum ER Electron spectrometer: MOS detector array Import time: 30 seconds

[0250] The EELS analysis locations of sample 11 after charging and discharging are shown in *1 and *2 in Figure 28A and in Figure 28B. As shown in *3, *4 and *5. *1 and *2 are from the outermost surface of the lithium cobalt oxide layer to the base The depth is approximately 100 nm toward the plate. *3 to *5 are similarly at a depth of approximately 30 nm. Yes. All of the analysis sites are grain boundaries or their vicinity, but *2, *4 and *5 are *1 And it is further inside the crystal grain than *3. Note that Figure 28B shows the pho enclosed by the white line in Figure 27. This is a magnified view of section 3-14.

[0251] Figure 29 shows the EELS spectra of the locations indicated by *1 to *5 in sample 11. Co- E after subtracting the background calculated from the binding energy side below L3 edge EL spectrum (Background subtracted EEL spect) rum) and calculated from the energy band between the Co-L3 edge and the Co-L2 edge. Spectrum of the L3 and L2 levels of cobalt, with background further subtracted. (Co-L2,3continuum subtracted spectrum) This is shown in the figure. Note that the background subtracted EEL spect. Rum is fitted to the original data using a power law model. Then the background was subtracted. Also, Co-L2,3continuum sub The tracted spectrum is used in the background with the power law fitting described above. From the removed data, we further developed a model of the cobalt scattering cross-section (Hartree-slat). Using the er cross-section model as a background function, subtract The results were obtained by [method / details omitted]. The area intensity ratio of L3 / L2 and the calculated cobalt valence are shown in Table 5.

[0252] [Table 5]

[0253] Figures 31A and 31B are cross-sectional TEM images of sample 12 after charging and discharging. EELS analysis The locations are indicated by *1 and *2 in Figure 31A, and *3, *4 and *5 in Figure 18B. The analysis areas are also grain boundaries and their vicinity, but *2, *4 and *5 are different from *1 and *3. This is also the interior of a crystal grain. Figure 31B is photo.2-1 enclosed by a white line in Figure 30. This is a magnified view of part 6.

[0254] The EELS spectra of *1 to *5 locations of sample 12 after charging and discharging are similarly shown in Figure 32. Table 6 shows the area intensity ratio of L3 / L2 and the calculated valence of cobalt.

[0255] [Table 6]

[0256] Tables 5 and 6 show that sample 11, which has a cap layer, has cobalt inside the crystal grains. A tendency for reduction to be suppressed became apparent. Therefore, by creating a cap layer, layered rock This suggests that the degradation of the salt-type crystal structure can be suppressed.

[0257] <Microelectron diffraction> Next, we analyzed the crystal structure of lithium cobalt oxide at and near the grain boundaries using microelectron diffraction. did.

[0258] Figure 25A is a cross-sectional TEM image of sample 11 before charging and discharging. The areas analyzed by micro-electron diffraction are shown. This is shown in *point1-1, *point1-2, and *point1-3 in Figure 25A. Figure 25A is a magnified view of the area enclosed by the black line in Figure 24, specifically photo 1-7.

[0259] Figure 25B shows the micro-electron diffraction pattern of the *point1-1 region. Transmitted light is O, diffraction spot... Parts of the T section were designated as 1, 2, and 3, and shown in the figure. *The analysis was performed on the point 1-1 section. Then, the interplanar spacing of plane 1 is 0.137 nm, the interplanar spacing of plane 2 is 0.143 nm, and the interplanar spacing of plane 3 is 0.4 The calculated value was 64 nm. The surface angles were ∠1O2=17°, ∠1O3=107°, and ∠2O3 =90°. At this time, the electron beam incidence direction was

[0120] , and from the interplanar spacing and interplanar angle 1 is a layered rock salt type crystal of -213, 2 is similarly -210, and 3 is similarly 00- The value was 3, suggesting that it has a layered rock salt type crystal structure. From these d values, *point The lattice constants for section 1-1 were calculated to be a = 2.86 (Å) and c = 13.9 (Å). .

[0260] Figure 26A shows the micro-electron diffraction pattern of the *point1-2 region. Transmitted light is O, and diffracted spoilage is shown. Parts of the set were designated as 1, 2, and 3, and shown in the figure. *The analysis was performed on the point 1-2 section. However, the interplanar spacing of plane 1 is 0.137 nm, the interplanar spacing of plane 2 is 0.143 nm, and the interplanar spacing of plane 3 is 0. The calculated value was 464 nm. The surface angles were ∠1O2=17°, ∠1O3=107°, and ∠2O 3 = 90°. At this time, the electron beam incidence direction is

[0120] , and from the interplanar spacing and interplanar angle... 1 is a layered rock salt type crystal of -213, 2 is similarly -210, and 3 is similarly 00- The value was 3, suggesting that it has a layered rock salt type crystal structure. From these d values, *point The lattice constants for section 1-2 were calculated to be a = 2.86 (Å) and c = 13.9 (Å). .

[0261] Figure 26B shows the micro-electron diffraction pattern of the *point1-3 region. Transmitted light is O, and diffracted spoilage is shown. Parts of the point were designated as 1, 2, and 3, and shown in the figure. *The analysis was performed on points 1-3. However, the interplanar spacing of plane 1 is 0.146 nm, the interplanar spacing of plane 2 is 0.139 nm, and the interplanar spacing of plane 3 is 0. The calculated value was 463 nm. The surface angles were ∠1O2=17°, ∠1O3=90°, and ∠2O3 =72°. At this time, the electron beam incidence direction was

[0120] , and from the interplanar spacing and interplanar angle, 1 is a layered rock salt crystal of -210, 2 is similarly -21-3, and 3 is similarly 00- There were 3, and it was thought to have a layered rock salt type crystal structure. From these d values ​​*point1 The lattice constants for the -3 region were calculated to be a = 2.92 (Å) and c = 13.9 (Å).

[0262] Figure 33A is a cross-sectional TEM image of sample 11 after charging and discharging. The areas analyzed by micro-electron diffraction are shown. This is shown in *point3-1, *point3-2, and *point3-3 in Figure 33A.

[0263] Figure 33B shows the micro-electron diffraction pattern of the *point3-1 region. Transmitted light is O, diffraction spot... Parts of the T section were designated as 1, 2, and 3, and shown in the figure. *The analysis was performed on part 3-1. Then, the interplanar spacing of plane 1 is 0.227 nm, the interplanar spacing of plane 2 is 0.183 nm, and the interplanar spacing of plane 3 is 0.4 It was calculated to be 75 nm. Also, the surface angles are ∠1O2=21°, ∠1O3=71°, ∠2O3= It was 50°. At this time, the electron beam incidence direction was [0-10], and from the interplanar spacing and interplanar angle, 1 is a layered rock salt crystal with 10⁻², 2 is similarly 10⁻⁵, and 3 is similarly 0⁰⁻³. Therefore, it was thought to have a layered rock salt type crystal structure. From these d values ​​*point3 The lattice constants for the -1 region were calculated to be a = 2.76 (Å) and c = 14.2 (Å).

[0264] Figure 34A shows the minute electron diffraction pattern of the *point3-2 region. Transmitted light is O, diffraction spot... Parts of the "T" were designated as 1, 2, and 3, and shown in the figure. *The analysis was performed on part 3-2. Then, the interplanar spacing of plane 1 is 0.226 nm, the interplanar spacing of plane 2 is 0.181 nm, and the interplanar spacing of plane 3 is 0.4 It was calculated to be 68 nm. Also, the surface angles are ∠1O2=22°, ∠1O3=71°, ∠2O3= It was 49°. At this time, the electron beam incidence direction was [0-10], and 1 is a layered rock salt type crystal. It is -102, 2 is similarly -105, 3 is similarly 003, and layered rock salt type It was thought to have a crystalline structure. From these d values, the lattice constant of the *point3-2 portion was calculated. The results were a = 2.74 (Å) and c = 14.1 (Å).

[0265] Figure 34B shows the micro-electron diffraction pattern of the *point3-3 region. Transmitted light is O, diffraction spot... A portion of the area is designated as 1 and shown in the figure. *When the part of point3-3 was analyzed, the interplane of 1 The gap was calculated to be 0.470 nm. At this time, the electron beam incidence direction is

[0003] , and 1 is the layer. It is a layered rock salt type crystal 003, and is thought to have a layered rock salt type crystal structure. Furthermore, calculating the lattice constant of the *point3-3 portion, we found that c = 14.0 (Å). The axis was not calculated because there was no corresponding d-value.

[0266] Figure 35A is a cross-sectional TEM image of sample 12 after charging and discharging. The areas analyzed by micro-electron diffraction are shown. This is shown in *point2-1, *point2-2, and *point2-3 in Figure 35A.

[0267] Figure 35B shows the micro-electron diffraction pattern of the *point2-1 region. Transmitted light is O, diffraction spot... Parts of the T section were designated as 1, 2, and 3, and shown in the figure. *The analysis was performed on part of point 2-1. Then, the interplanar spacing of plane 1 is 0.125 nm, the interplanar spacing of plane 2 is 0.115 nm, and the interplanar spacing of plane 3 is 0.2 It was calculated to be 34 nm. Also, the surface angles are ∠1O2=29°, ∠1O3=96°, ∠2O3= It was 66°. At this time, the electron beam incidence direction was

[0010] , and 1 is the 2 of the layered rock salt type crystal. 0-1, 2 is similarly 205, 3 is similarly 006, and the layered rock salt type crystal structure It was thought to have a structure. From these d values, the lattice constant of the *point2-1 portion was calculated. Then, a = 2.91 (Å) and c = 14.1 (Å).

[0268] Figure 36A shows the micro-electron diffraction pattern of the *point2-2 region. Transmitted light is O, diffraction spot... Parts of the T section were designated as 1, 2, and 3, and shown in the figure. *The analysis was performed on the point 2-2 section. Then, the interplanar spacing of plane 1 is 0.126 nm, the interplanar spacing of plane 2 is 0.115 nm, and the interplanar spacing of plane 3 is 0.2 It was calculated to be 34 nm. Also, the surface angles are ∠1O2=29°, ∠1O3=95°, ∠2O3= It was 66°. At this time, the electron beam incidence direction was

[0010] , and 1 is the 2 of the layered rock salt type crystal. 0-1, 2 is similarly 205, and 3 is similarly 006, indicating a layered rock salt type crystal structure. It was thought to have these properties. From these d values, the lattice constant of the *point2-2 portion was calculated. Then, a = 2.91 (Å) and c = 14.1 (Å).

[0269] Figure 36B shows the micro-electron diffraction pattern of the *point2-3 region. Transmitted light is O, diffraction spot... A portion of the "T" is designated as 1 and shown in the figure. *When the part of point2-3 was analyzed, 1 The interplanar spacing was calculated to be 0.474 nm. At this time, the electron beam incidence direction is

[0003] , 1 is 003 of the layered rock salt type crystal, and was thought to have a layered rock salt type crystal structure. From the d-value, the lattice constant of the *point2-3 portion can be calculated as c = 14.21 (Å). The a-axis was not calculated because there was no corresponding d-value.

[0270] As described above, the lattice constant of sample 11 without a cap layer after charging and discharging is the same as the lattice constant of sample 11 before charging and discharging. The lattice constant tended to be larger than that of lithium luteate. This is because reduction of cobalt occurs. It is presumed to be folded.

[0271] On the other hand, in sample 12, which has a cap layer, the a-axis tends to be smaller on average even after charging and discharging. This indicates that the valence of cobalt is high, and the reduction of cobalt is suppressed. ru.

[0272] <Charge-discharge cycle> Next, secondary batteries were fabricated using samples 11 and 12, and their charge-discharge cycle characteristics were examined. I evaluated it.

[0273] Samples 11 and 12 were used as the positive electrode and lithium metal as the counter electrode, with a CR2032 tubing. A coin-shaped battery cell with dimensions of 20mm in diameter and 3.2mm in height was fabricated.

[0274] The electrolyte in the electrolyte solution is 1 mol / L lithium hexafluoride phosphate (LiPF6). The electrolyte consists of ethylene carbonate (EC) and diethyl carbonate (DEC). A mixture of C:DEC = 3:7 (by volume) with vinylene carbonate as an additive. A solution containing 2 wt% of VC was used.

[0275] A 25 μm thick polypropylene was used for the separator.

[0276] The positive electrode and negative electrode cans were made of stainless steel (SUS).

[0277] The cycle test was performed under the following conditions: Charging voltage was 4.2V. Measurement temperature was 25°C. Charging is CC / CV (0.2C, 0.1C cut), discharging is CC (0.1C, 2.5V) (cut) and a 10-minute break was provided before the next charge. In this embodiment, 1C is The value was set to 137 mA / g.

[0278] Figure 37 shows the results of the charge-discharge cycle test. Compared to sample 12 without a cap layer, The positive electrode of sample 11, which had a cap layer, exhibited extremely good charge-discharge cycle characteristics.

[0279] <Impedance> During the above charge-discharge cycle test, the impedance of the secondary battery was measured.

[0280] In this embodiment, the electrochemical phenomena occurring in a secondary battery according to one aspect of the present invention are as shown in Figure 38A. We will analyze it by replacing it with an equivalent circuit.

[0281] Here, Rs is the electrical resistance of the electrode and the resistance of the electrolyte. Here, the electrical resistance of the electrode is the resistance of the electrolyte. This includes all the simple electrical resistance contained within the in-cell. Furthermore, the resistance of the electrolyte refers to the resistance of the solution. This refers to the ion diffusion resistance within the material.

[0282] R1 may be written as Rf or Rsurface, and it represents the impedance of a secondary battery. This is the high-frequency component. R1 includes the resistance of lithium ion diffusion at the interface between the positive electrode and the electrolyte. ru.

[0283] CPE1 (constant phase element, electrical double layer capacitance) is porous. This is the capacitance that reproduces the behavior at the electrode.

[0284] R2 is sometimes written as Rct and is a low-frequency component. Li ions are active in R2 at the positive electrode. The process of deinserting and reinserting into a material layer (LiCoO2 in this example) (charge transfer) The resistor r) is included.

[0285] Ws1 is the resistance associated with lithium diffusion in the solid.

[0286] The impedance typically takes the form of a graph like the one shown in Figure 38B. The graph shows the influence of each component. The scope of the action was indicated.

[0287] The impedance of sample 11 is shown in Figure 39, and the impedance of sample 12 is shown in Figure 40. The graphs shown are for the 2nd and 50th cycles, respectively. The measuring device is from Solartron. Using the CELLTEST multi-channel electrochemical measurement system, an AC voltage of 10 The mV was swept from 0.001 Hz to 1 MHz. The measurement temperature was 25°C. Before measuring the dance voltage, the battery was charged to 4.2V at 0.2C and left for 2 hours. The OCV at this time was After 2 cycles, sample 11 showed 4.1308V, and after 50 cycles it showed 4.060V. It was 7V. After 2 cycles of sample 12 it was 4.1162V, and after 50 cycles it was 4.0 It was 005V.

[0288] As shown in Figure 40, in sample 12, the impedance at cycles 2 and 50 is Comparing them, R1 (high-frequency component) is particularly increased. Therefore, the lithium diffusion pathway, For example, degradation occurs at the interface between the positive electrode active material layer and the electrolyte, as well as at some grain boundaries, as shown in Figure 3. This is presumed to be the cause of the deterioration in charge-discharge cycle characteristics shown in 7.

[0289] On the other hand, as shown in Figure 39, in sample 11, the impedance of the 2nd cycle and the 50th cycle The increase in R1 when comparing the performance is relatively small. Therefore, the effect of the cap layer is that the film is produced It can be inferred that the growth has been suppressed. Also, R2 (low-frequency component) has increased significantly. Therefore, it is presumed that the crystal structure of LiCoO2 is degrading. [Explanation of symbols]

[0290] 100: Positive electrode, 101: Positive electrode active material layer, 102: Cap layer, 103: Positive electrode current collector, 10 4: Base film, 110: Substrate, 111: Substrate, 200: Secondary battery, 201: Secondary battery, 20 2: Secondary battery, 203: Solid electrolyte layer, 204: Negative electrode active material layer, 205: Negative electrode current collector, 2 06: Protective layer, 209: Cap layer, 210: Negative electrode, 211: Negative electrode, 212: Negative electrode, 21 3: Solid electrolyte layer, 214: Undercoat film, 215: Positive electrode current collector, 220: Separator, 221 : Electrolyte, 222: Outer casing, 223a: Lead electrode, 223b: Lead electrode, 230: Two Secondary battery, 231: Secondary battery< / eels> < / tem>

Claims

[Claim 1] A positive electrode for a secondary battery, It has a base film, a positive electrode active material layer, and a cap layer. The aforementioned underlayer has a titanium compound containing nitrogen, The positive electrode active material layer has lithium cobalt oxide, The aforementioned cap layer has a titanium compound containing oxygen, and is a positive electrode for a secondary battery.

Images