JP2012079448A - Electrode plate for nonaqueous electrolyte secondary battery, method for manufacturing the same, nonaqueous electrolyte secondary battery, and battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode plate for nonaqueous electrolyte secondary battery which is excellent in output/input characteristics, a method for manufacturing the same, as well as a nonaqueous electrolyte secondary battery and a battery pack which use the same.SOLUTION: An electrode plate for nonaqueous electrolyte secondary battery includes a current collector, and an electrode active material layer formed on at least part of a surface of the current collector. The electrode active material layer contains active material particles, and a metal oxide, indicating the insertion and elimination reaction of lithium-ions, as a binding material. The metal oxide is configured to be a coating layer for coating the plurality of active material particles so that a plurality of projections exist on the surface of the coating layer.

Description

  The present invention relates to an electrode plate used for a non-aqueous electrolyte secondary battery, a method for producing the electrode plate, a non-aqueous electrolyte secondary battery, and a battery pack.

  A non-aqueous electrolyte secondary battery represented by a lithium ion secondary battery has a high energy density and a high voltage, and has a memory effect during charging / discharging (when the battery is charged before it is completely discharged, Since there is no phenomenon in which the capacity decreases, it is used in various fields such as portable devices and large devices.

At present, efforts are being made to reduce CO ₂ emissions on a global scale. Plug-in hybrids that can greatly contribute to CO ₂ reduction by reducing the dependence on oil and enabling driving with low environmental impact. There is an urgent need to develop and spread next-generation clean energy vehicles such as automobiles and electric cars. Driving power that does not depend on gasoline is essential for the development and popularization of these next-generation clean energy vehicles. Non-aqueous electrolyte secondary batteries represented by lithium ion secondary batteries are expected as the driving force.

  The non-aqueous electrolyte secondary battery includes a positive electrode plate, a negative electrode plate, a separator, and an organic electrolyte. And as said positive electrode plate and negative electrode plate, what equips the collector surface, such as metal foil, with the electrode active material layer formed by apply | coating an electrode active material layer forming liquid is generally used.

  The electrode active material layer forming liquid is composed of active material particles that can be charged / discharged by exhibiting lithium ion insertion / release reaction, resin binder, and conductive material (however, when the active material also exhibits a conductive effect) In some cases, the conductive material may be omitted), or, if necessary, other materials may be used and kneaded and / or dispersed in an organic solvent to prepare a slurry. Then, the electrode active material layer forming liquid is applied to the current collector surface, then dried to form a coating film on the current collector, and if necessary, an electrode plate having the electrode active material layer is manufactured by pressing. The method is general (for example, paragraphs [0019] to [0026], patent document 1 [claim 1], and paragraphs [0051] to [0055]).

  At this time, the active material particles contained in the electrode active material layer forming liquid are particulate compounds dispersed in the solution, and are fixed to the current collector surface only by being applied to the current collector surface. It is a difficult material. Accordingly, even when an electrode active material layer forming liquid not containing a resin binder is applied to a current collector and dried to form a coating film, the coating film is easily peeled off from the current collector. Therefore, an electrode active material layer in a conventional electrode plate is generally formed by fixing active material particles on a current collector through a resin binder, and the resin binder The material was essentially an essential constituent.

JP 2006-310010 A JP 2006-107750 A

  As described above, the nonaqueous electrolyte secondary battery is expected to be used as a driving force for next-generation clean energy. However, not only for automobiles and power tools, but also when used in relatively small devices such as cellular phones, the devices tend to be multifunctional, so high input / output characteristics There is still a need for improvement.

  The present inventors diligently studied to improve the input / output characteristics of the electrode plate for a non-aqueous electrolyte secondary battery, and focused on the presence of a resin binder in the electrode active material layer. As described above, the resin binder has been used as an essential component for substantially forming the electrode active material layer. However, in the conventional electrode plate in which the active material particles are fixed on the current collector only with the resin binder as the binder, the volume of the electrode active material layer increases due to the presence of the resin binder, and the electrode As a result of reducing the capacity, and the presence of a binder between the active material particles, the electrical resistance of the electrode plate is increased, which hinders the movement of lithium ions and electrons, etc. The problem was inferred. As a result, it has been inferred that the resin binder is one of the negative factors for increasing the output of the electrode plate.

  The present invention has been accomplished in view of the above circumstances. That is, the present invention provides an electrode plate for a non-aqueous electrolyte secondary battery excellent in input / output characteristics, a method for producing the electrode plate for a non-aqueous electrolyte secondary battery, and non-aqueous electrolysis using the electrode plate. An object is to provide a liquid secondary battery and a battery pack.

  The present inventors have found that an active material particle can be fixed to the surface of a current collector by the presence of a metal oxide as a binding material to constitute an electrode active material layer. In the electrode active material layer, the metal oxide constitutes a coating layer that coats the plurality of active material particles, and the surface of the coating layer has a plurality of protrusions, and By identifying that it is a metal oxide exhibiting lithium ion insertion / release reaction, it was found that an electrode plate for a non-aqueous electrolyte secondary battery having excellent input / output characteristics can be provided, and the present invention has been completed. .

  In addition, as one means for fixing the active material particles on the current collector, the present inventors have produced a metal oxide exhibiting a lithium ion insertion / desorption reaction by means capable of causing a metal reaction such as heating. One or more possible metal element-containing compounds are selected in advance, and contain at least the metal element-containing compound, active material particles, and a shape-changing agent capable of making the generated metal oxide into a desired shape. After the solution to be applied is applied to the current collector surface, the metal element-containing compound is reacted to produce a metal oxide that can undergo lithium ion insertion and desorption reaction on the current collector surface and has a desired shape. In addition, the inventors have found that the active material particles can be fixed to the surface of the current collector through the metal oxide, and have completed the invention of the method for producing an electrode plate for a non-aqueous electrolyte secondary battery.

That is, the present invention
(1) A non-aqueous electrolyte secondary battery electrode plate comprising a current collector and an electrode active material layer formed on at least a part of the surface of the current collector, wherein the electrode active material layer comprises: Active material particles and a binding material are contained, and the binding material is a metal oxide exhibiting a lithium ion insertion / release reaction, and the metal oxide has a coating layer covering a plurality of active material particles. A nonaqueous electrolyte secondary battery electrode plate, wherein the surface of the coating layer has a plurality of protrusions;
(2) The nonaqueous electrolytic solution according to (1), wherein at least the surface opposite to the surface on the active material particle side to be coated is contracted and raised in the coating layer Secondary battery electrode plate,
(3) The electrode plate for a non-aqueous electrolyte secondary battery according to (1) or (2), wherein the metal oxide is a lithium composite oxide,
(4) The metal oxide is a composite oxide of at least one metal selected from cobalt, nickel, manganese, iron, and titanium and lithium (1) ) To (3), the electrode plate for a non-aqueous electrolyte secondary battery,
(5) The electrode plate for a nonaqueous electrolyte secondary battery according to any one of (1) to (4), wherein the active material particles and the metal oxide are the same compound. ,
(6) The electrode active material layer is characterized in that the active material particles are fixed to each other by the binding material, and the active material particles are fixed to the current collector by the binding material. The electrode plate for a non-aqueous electrolyte secondary battery according to any one of (1) to (5) above,
(7) The non-aqueous electrolyte secondary battery according to any one of (1) to (6), wherein the binder material covers at least a part of the surface of the active material particles. Electrode plate,
(8) A non-aqueous electrolyte secondary battery comprising at least a positive electrode plate, a negative electrode plate, a separator provided between the positive electrode plate and the negative electrode plate, and an electrolyte containing a non-aqueous solvent, Either the positive electrode plate or the negative electrode plate, or both are the electrode plates for a nonaqueous electrolyte secondary battery according to any one of (1) to (7) above. Electrolyte secondary battery,
(9) An electrode active material layer forming liquid containing at least active material particles and one or more metal element-containing compounds is applied to at least a part of the current collector to form a coating film An electrode active material containing the metal oxide and the active material particles on the current collector by reacting a metal element-containing compound contained in the coating film with the coating step to produce a metal oxide An electrode active material layer forming step for forming a layer in this order, and the coating is performed so that the metal oxide generated in the electrode active material layer forming step becomes a metal oxide exhibiting a lithium ion insertion / release reaction. A shape for selecting in advance the metal element-containing compound used in the process, and forming the metal oxide into a coating layer that covers a plurality of active material particles and has a plurality of protrusions on the surface. The above-mentioned electrode active material Method for producing a non-aqueous electrolyte secondary battery electrode plate, characterized in that to be contained in the layer-forming liquid,
(10) The method for producing an electrode plate for a non-aqueous electrolyte secondary battery according to (9), wherein the shape change agent is a coupling agent,
(11) The method for producing an electrode plate for a nonaqueous electrolyte secondary battery according to (9) or (10), wherein at least a lithium salt is used as the metal element-containing compound,
(12) The metal element-containing compound described above, wherein at least one metal salt containing a metal selected from cobalt, nickel, manganese, iron, and titanium and a lithium salt are used ( 9) From the manufacturing method of the electrode plate for nonaqueous electrolyte secondary batteries as described in any one of (11),
(13) A storage case, a nonaqueous electrolyte secondary battery including a positive electrode terminal and a negative electrode terminal, and a protection circuit having an overcharge and overdischarge protection function are provided, and the storage case includes the nonaqueous electrolyte secondary battery. In the battery pack configured to house the battery and the protection circuit, the non-aqueous electrolyte secondary battery includes a positive electrode plate, a negative electrode plate, a separator provided between the positive electrode plate and the negative electrode plate, A non-aqueous electrolyte secondary battery comprising at least an electrolyte containing a non-aqueous solvent,
Either one of the positive electrode plate or the negative electrode plate, or both are the electrode plates for a nonaqueous electrolyte secondary battery according to any one of (1) to (7). ,
Is a summary.

  The present invention makes it possible to fix the active material particles in the electrode active material layer on the current collector with a metal oxide. In the present invention, in the electrode active material layer, the metal oxide constitutes a coating layer that covers a plurality of active material particles, and the surface of the coating layer has a plurality of protrusions. It is possible to provide an electrode plate for a non-aqueous electrolyte secondary battery that exhibits excellent input / output characteristics.

  Moreover, according to the manufacturing method of the electrode plate for nonaqueous electrolyte secondary batteries of this invention, the electrode plate for nonaqueous electrolyte secondary batteries of this invention can be manufactured with an easy method and a general purpose material. it can. Further, the metal oxide formed by adding a shape change agent to the electrode active material layer forming liquid is used as a coating layer that coats a plurality of active material particles, and a plurality of coatings are formed on the surface of the coating layer. It is possible to form so that there are projections. According to the method for producing an electrode plate for a non-aqueous electrolyte secondary battery of the present invention, it is possible to easily produce an electrode plate for a non-aqueous electrolyte secondary battery with greatly improved input / output characteristics. is there.

  In addition, the nonaqueous electrolyte secondary battery of the present invention and the battery pack of the present invention using the electrode plate of the present invention as a positive electrode plate and / or a negative electrode plate can improve the input / output characteristics of the electrode plate of the present invention. Accordingly, it is possible to improve the input / output performance of the nonaqueous electrolyte secondary battery itself and the input / output performance of the battery pack itself.

1A is a schematic diagram showing a cross section of the electrode plate of the present invention, 1B is a schematic diagram showing the surface of the electrode active material layer in the electrode plate of the present invention, and 1C is a partially enlarged schematic diagram of 1B. . 2 is a scanning electron micrograph (magnification 10,000 times) obtained by photographing the surface of the electrode active material layer of Example 1. FIG. 2 is a scanning electron micrograph (magnification of 50,000 times) obtained by photographing the surface of the electrode active material layer of Example 1. FIG. 4 is a scanning electron micrograph (magnification 10,000 times) obtained by photographing the surface of the electrode active material layer of Example 2. FIG. 4 is a scanning electron micrograph (magnification of 50,000 times) obtained by photographing the surface of the electrode active material layer of Example 2. FIG. It is a cyclic voltammogram which shows the result of the cyclic voltammetry test using the metal oxide which shows lithium insertion elimination reaction. It is a cyclic voltammogram which shows the result of the cyclic voltammetry test using the metal oxide which does not show lithium insertion elimination reaction. It is a schematic sectional drawing which shows the one aspect | mode of the lithium ion secondary battery of this invention. It is a general | schematic exploded view which shows the one aspect | mode of the battery pack of this invention. (10A) is a scanning electron micrograph (magnification 10,000 times) of the surface of the electrode active material layer of Comparative Example 1, and (10B) is a photograph of the surface of the electrode active material layer of Comparative Example 1. It is a scanning electron micrograph (magnification 50,000 times). 4 is a scanning electron micrograph (magnification 10,000 times) of the surface of the electrode active material layer of Comparative Example 2. 12A to 12D are schematic cross-sectional views illustrating exemplary embodiments of the current collector used in the present invention.

  Below, the electrode plate for non-aqueous electrolyte secondary batteries of the present invention (hereinafter sometimes simply referred to as “electrode plate”) and the form for carrying out the non-aqueous electrolyte secondary battery will be described in order.

[Electrode plate for non-aqueous electrolyte secondary battery]
FIG. 1 shows an embodiment of an electrode plate for a non-aqueous electrolyte secondary battery of the present invention. As shown in FIG. 1A, the present invention provides a nonaqueous electrolyte secondary battery electrode plate comprising a current collector 1 and an electrode active material layer 2 formed on at least a part of the surface of the current collector 1. 10 can be configured. The electrode active material layer 2 has a plurality of protrusions 8 on the surface of the binding material, which is a metal oxide that exhibits a lithium ion insertion / release reaction, as schematically shown in FIGS. 1B and 1C. In addition, optionally, the surface opposite to the surface on the active material particle 21 side to be coated may be contracted and raised. As shown in FIG. 1B, the surface of the surface that shrinks and rises as described above may have a pleated layer structure. Although there are a plurality of protrusions 8, there are gaps between adjacent protrusions 8. As shown in FIG. 1B, the electrode active material layer 2 has gaps 6 between the pleated coating layers 7, thereby allowing the non-aqueous electrolyte to penetrate. Further, the pleated coating layer 7 may completely cover the active material particles 21 contained in the electrode active material layer 2, or a part of the active material particles 21 may be pleated coating layer 7. You may have the part which is not coat | covered. Although not shown, the binding material in the present invention is a mode in which the surface on the side opposite to the surface on the active material particle 21 side to be coated shrinks and rises, the form of the protrusion is not particularly limited, As described above, it may be a coating layer having a pleated layer structure, or may be a coating layer having a knurled layer structure, and a pleated coating layer and a hump-shaped coating layer are mixed. It may be.

  The electrode plate of the present invention can improve input / output characteristics by adopting the above-described configuration. In addition, since the metal oxide is a metal oxide that exhibits a lithium ion insertion / release reaction, it can also act as an active material in the electrode active material layer, so that the discharge capacity of the electrode plate (hereinafter referred to as “electrode capacity”). Is also preferable in that it can be increased. Further, in many embodiments of the electrode plate of the present invention, the electrode active material layer is laminated directly on the current collector due to the presence of the binder material particles, so that the electrode active material layer and the current collector The movement of electrons between them is very smooth.

  In the case of explaining the present invention, or in the case of being fixed by a binding substance in one aspect of the present invention, the following two aspects are included. That is, the above-described fixing mode is between the objects to be fixed (for example, between the active material particles, between the active material particles and the current collector surface, or when using a conductive material, between the conductive material and the active material particles, When the metal oxide as the binder is interposed between the conductive material particles and the like (hereinafter referred to as “fixing mode 1”), the adherends are in direct contact with each other and surround the contact portion. And the case where the objects to be bonded are fixed together by the presence of the binding substance (hereinafter referred to as “fixing mode 2”). In many embodiments of the present invention, either one or both of the fixing modes 1 and 2 described above are present in the electrode active material layer. In particular, the sticking mode 2 tends to increase as the particle diameter of the active material particles and conductive material particles contained in the electrode active material layer decreases.

  In the case where the electrode active material layer is configured to include either or both of the fixing modes 1 and 2, the present invention exhibits an excellent effect in terms of improving the conductivity. In order to understand the above effect, attention is paid particularly to the adhesion between the conductive material particles in the electrode active material layer containing the conductive material particles. When the conductive material particles are fixed to each other by the fixing mode 1, the binding material of the present invention is a metal oxide. Therefore, the conductive material is more conductive than the electrode plate using only the conventional resin binding material. It is unlikely to be an obstacle to the exchange of electrons between particles. Furthermore, when the conductive material particles are fixed by the fixing mode 2, since the particles are in direct contact with each other, the flow of electrons is naturally smooth, and excellent conductivity is ensured. . The same can be said for the above-mentioned effect regarding the adhesion between the conductive material particles and the active material particles. In addition, even at the boundary between the current collector and the electrode active material layer, the current collector surface and the active material particles or the conductive material particles are fixed through the binder, or they are in direct contact with each other. Then, it is fixed by the presence of the binding substance around the contact portion. Therefore, the flow of electrons between the current collector and the electrode active material layer is smooth for the same reason as described above. That is, in the electrode plate of the present invention, the metal oxide is present in the electrode active material layer as a binding material, and various constituent materials are fixed by the fixing modes 1 and / or 2, whereby the electric resistance is increased. It is possible to keep it low, and it is particularly preferable that the fixing modes 1 and 2 are mixed.

  The electrode plate of the present invention can be used as either a positive electrode plate or a negative electrode plate of a non-aqueous electrolyte secondary battery, or the electrode plate of the present invention may be used for both the positive electrode plate and the negative electrode plate.

  When the electrode plate of the present invention is used as a positive electrode plate, the input / output performance is higher than when only the resin binder is used. In addition, since the electrode plate of the present invention can substantially increase the proportion of the active material in the electrode by designing the binder material to act as an active material, the discharge capacity of the electrode plate can be increased. Is excellent in that it can be increased. Furthermore, the electrode plate of the present invention has a wide range of applications in that many metal oxides can be applied, and in addition, it can be used in combination with a conventional negative electrode plate, which is preferable.

  In addition, when the electrode plate of the present invention is used as a negative electrode plate, the electrode plate of the present invention is excellent in that the input / output performance is high and the electrode capacity can be increased similarly to the positive electrode plate. ing. In addition, the electrode plate of the present invention has excellent adhesion between a metal substrate such as copper or aluminum and a metal oxide, and further, a metal oxide film present around the negative electrode active material particles is SEI (Solid Electrolyte Interface). From the viewpoint of improving the cycle characteristics as a result.

  In particular, when the electrode plate of the present invention is used for both positive and negative electrodes, desirable effects such as high-speed charge / discharge and good cycle characteristics are exhibited. Below, the form of the electrode plate of this invention is demonstrated in detail. Further, the present invention will be described by dividing it into a positive electrode plate and a negative electrode plate as necessary. Unless otherwise specified, the electrode plate of the present invention includes both the positive electrode plate and the negative electrode plate, and the active material. The term “particle” is used to mean both positive electrode active material particles and negative electrode active material particles.

(Current collector)
The current collector used in the present invention is not particularly limited as long as it is generally used as a negative electrode current collector in a negative electrode plate for a nonaqueous electrolyte secondary battery. For example, an aluminum foil, a nickel foil, a copper foil or the like formed from a simple substance or an alloy is preferably used, but is not limited thereto. The current collector used in the present invention may be a current collector that has been subjected to surface processing on the surface on which the electrode active material layer is to be formed, if necessary. Examples of the current collector that has been subjected to surface processing treatment include those in which a conductive material is laminated, surface treatments such as chemical polishing treatment, corona treatment, and oxygen plasma treatment. Alternatively, the current collector may be physically provided with any unevenness on the surface.

  An example of the current collector used in the present invention will be described more specifically. For example, as shown in FIG. 12A, as the current collector 1 used for the electrode plate 20 for a non-aqueous electrolyte secondary battery, only the current collecting base material 3 such as a metal foil itself having a current collecting function may be used. it can. Examples of the current collecting base 3 include the above-described aluminum foil, nickel foil, carbon sheet, and the like. In such a case, the electrode active material layer 2 is provided on at least a part of the surface 101 of the current collecting base material 3.

  Moreover, as an example of a different collector, as shown in FIG. 12B, a collector base material 3 that itself has a collector function as a collector used for the electrode plate 20 ′ for a nonaqueous electrolyte secondary battery. It is possible to use a current collector 1 ′ in which an arbitrary conductive layer 4 having conductivity is provided on the upper surface. The electroconductive layer 4 should just show electroconductivity of the grade which does not prevent the movement of the electron between the electrode active material layer 2 and the current collection base material 3. FIG. For example, the conductive layer 4 is a laminated layer made of copper or a copper alloy, a layer in which arbitrary conductive fine particles are deposited by plating or sputtering, or a layer in which one or more conductive thin films are provided. However, the present invention is not limited to these examples. In the current collector 1 ′, the surface of the conductive layer 4 becomes the surface 102 of the current collector 1 ′, and the electrode active material layer 2 is provided on at least a part of the surface 102. In addition, in FIG. 12B, the aspect in which the arbitrary electroconductive layer 4 is one layer was shown. However, the configuration of the current collector 1 ′ is not limited to this, and the conductive layer 4 may have a stacked configuration in which two or more arbitrary conductive layers are stacked.

  As an example of a different current collector, as shown in FIG. 12C, a current collector base material having a current collecting function as a current collector used for the electrode plate 20 '' for a nonaqueous electrolyte secondary battery. A current collector 1 ″ in which an arbitrary intermittent layer 5 formed intermittently is provided on the upper surface of 3 can be used. The intermittent layer 5 may be a conductive layer similar to the conductive layer 4 described above, or may be a layer that does not exhibit conductivity. That is, in the electrode plate 20 ″ for the non-aqueous electrolyte secondary battery, the surface of the current collector 1 ″ is the surface 103 which is the surface of the intermittent layer 5 and the current collector base where the intermittent layer 5 is not provided. It consists of surface 103 'which is the surface of material 3 itself. At this time, the electrode active material layer 2 can be formed so as to be in contact with both the surface 103 and the surface 103 ′. In the electrode plate 20 ″ for a nonaqueous electrolyte secondary battery, the intermittent layer 5 may or may not have conductivity. Even if the intermittent layer 5 is a non-conductive layer, the electrode active material layer 2 is in direct contact with the current collector base 3 on the surface 103 ′ of the current collector 1 ″. And the current collector 1 ″ ensure the movement of electrons. However, from the viewpoint of reducing the electrical resistance of the electrode plate 20 ″ for the nonaqueous electrolyte secondary battery itself, it is preferable that the intermittent layer 5 also exhibits conductivity.

  When the intermittent layer 5 exhibits conductivity, as shown in FIG. 12D, an electrode active material layer 2 ′ is selectively provided only on the intermittent layer 5 on the surface of the current collector 1 ″. You may comprise electrode board 20 '' 'for nonaqueous electrolyte secondary batteries. That is, the electrode active material layer 2 ′ may be selectively provided on at least a part of the surface 103 of the surface of the current collector 1 ″. Alternatively, although not shown, when the intermittent layer 5 does not exhibit conductivity, the electrode active material layer 2 ′ may be selectively provided on at least a part of the surface 103 ′ of the current collector 1 ″.

  The description of the current collector described above does not limit the current collector used in the present invention. As exemplified above, the current collector used in the present invention may be only a current collecting base material having a current collecting function, and in such an embodiment, the surface of the current collector on which the electrode active material layer is provided is defined. , Refers to the surface of the current collecting substrate. Alternatively, in the present invention, the current collector may have a current collecting base material having a current collecting function and an arbitrary laminated layer provided on the current collecting base material. In such an embodiment, the surface of the current collector on which the electrode active material layer is provided is within the range in which the movement of electrons is ensured in at least one region between the current collector base material and the electrode active material layer. It refers to the surface, or the surface of the current collecting base material on which the laminated layer is not provided, or the surface of the current collecting base material on which the surface of the laminated layer is not provided.

  As the current collector used in the present invention, one having a heat resistant temperature of 800 ° C. or lower, further 600 ° C. or lower, and particularly 400 ° C. or lower can be selected. The selection of the current collector is determined by the relationship with the temperature condition in the electrode active material layer forming step in the production method of the present invention described later. In the manufacturing method of this invention, when an electrode active material layer formation process is a heating process, an electrode active material layer can be directly formed on a collector at the heating temperature of 400 degrees C or less, for example. Accordingly, the current collector can be selected to have a heat resistant temperature of 800 ° C. or lower, more preferably 600 ° C. or lower, and particularly 400 ° C. or lower, and an electrode active material layer is directly formed on the current collector. An electrode plate of the present invention can be provided. The electrode active material layer directly provided on the current collector having low heat resistance of 400 ° C. or lower is preferably a combination in which the active material particles and the binding material are made of the same compound. It is not limited.

  The thickness of the current collector is not particularly limited as long as it can be used as a current collector for a positive electrode plate or a negative electrode plate for a non-aqueous electrolyte secondary battery, but is preferably 10 to 200 μm. More preferably, it is 50 μm.

(Electrode active material layer)
The electrode active material layer in the present invention includes at least active material particles and a metal oxide that exhibits a lithium ion insertion / release reaction as a binding material.

  As described above, the metal oxide that is a binding material in the present invention constitutes a coating layer that covers a plurality of active material particles, and the surface of the coating layer has a plurality of protrusions. With the above features. In order to show the said characteristic, the scanning electron micrograph which image | photographed the surface of the electrode active material layer in this invention is shown to FIGS. FIGS. 2 and 3 are electron micrographs taken from the surface of the electrode active material layer taken in Example 1 described later, and FIGS. 4 and 5 are electron micrographs taken from the surface of the electrode active material layer of Example 2 described later.

  FIG. 2 shows that in the electrode active material layer in one embodiment of the present invention, a metal oxide as a binding material covers a plurality of active material particles and a conductive material to form a pleated coating layer. Yes. Then, when the magnification is further increased and the electrode active material layer shown in FIG. 2 is observed, it is understood that there are a plurality of protrusions on the surface of the coating layer as shown in FIG.

  FIG. 4 shows that in the electrode active material layer according to one embodiment of the present invention, a metal oxide as a binding material covers a plurality of active material particles and a conductive material to form a hump-like coating layer. Yes. Then, when the magnification is further increased and the electrode active material layer shown in FIG. 4 is observed, it is understood that there are a plurality of protrusions on the surface of the coating layer as shown in FIG.

  Moreover, in the embodiment shown in FIG. 3 or FIG. 5, the protrusions present on the surface of the coating layer are needle-like (FIG. 3) or scale-like (FIG. 5), and the maximum length is about 1 nm to 1000 nm. In addition, a large number of protrusions are densely gathered in an area of about 80% to 100% of the surface area of the entire coating layer.

  The characteristic form of the metal oxide, which is the binder in the electrode active material layer, described above greatly contributes to the improvement of the input / output characteristics of the electrode plate of the present invention. That is, since the metal oxide that coats the active material particles forms a coating layer that coats the active material particles, and there are a plurality of protrusions on the surface of the coating layer, the total surface area is large. Here, since the metal oxide in the present invention exhibits a lithium ion insertion / release reaction, the metal oxide can act as an active material depending on the design when the electrode plate of the present invention is used in a battery. Is possible. Therefore, in the embodiment of the present invention in which the metal oxide functions as both a binder and an active material, the large amount of surface area of the metal oxide facilitates the entry and exit of lithium ions, resulting in input / output characteristics. It works favorably for improving.

  Furthermore, if the coating layer is an aspect of the present invention in which the surface opposite to the surface on the active material particle side to be coated shrinks and rises, the increase in the total surface area of the coating layer, that is, the metal oxide is further increased. Since it becomes prominent, the input / output characteristics are more excellent.

  In the electrode plate of the present invention, the thickness of the electrode active material layer can be appropriately designed in consideration of the electrode capacity and input / output characteristics required for the electrode plate. In general, the thickness of the electrode active material layer is designed to be 200 μm or less, more generally 100 μm or more and 150 μm or less. However, in the present invention, the electrode active material layer can be formed very thin. Therefore, although depending on the particle diameter of the active material particles used, an electrode active material layer having an electrode active material layer thickness of 300 nm to 200 μm can be formed. From the viewpoint that the electrode capacity can be improved while improving the input / output characteristics, the thickness of the electrode active material layer is particularly preferably 300 nm to 150 μm, and more preferably 500 nm to 100 μm. That is, when the thickness of the electrode active material layer is thin as in the above range, the active material particles used have a small particle diameter, and are at least a particle diameter equal to or smaller than the film thickness of the electrode active material layer. Means. In addition, when the thickness of the electrode active material layer is as thin as the above range, the distance between the active material particles and the current collector in the electrode active material layer is shortened, so that the resistance of the electrode plate is reduced. Can do. In the present invention, the lower limit of the film thickness of the electrode active material layer mainly depends on the particle diameter of the active material particles used, and the film thickness is further reduced as the particle diameter of usable active material particles is reduced. It is possible.

Active material particles:
The positive electrode active material particles contained in the electrode active material layer in the positive electrode plate of the present invention may be active material particles that exhibit a lithium ion insertion / release reaction generally used in positive electrode plates for non-aqueous electrolyte secondary batteries. There is no particular limitation. The above Examples of the positive electrode active material, for example _{LiCoO 2, LiMn 2 O 4,} LiNiO 2, LiFeO 2, LiTiO 2, LiFePO 4 and the like lithium composite oxides such as. In addition, as the negative electrode active material particles contained in the electrode active material layer in the negative electrode plate of the present invention, active material particles generally exhibiting lithium ion insertion and desorption reactions used in negative electrode plates for non-aqueous electrolyte secondary batteries If it is, it will not be specifically limited. Specific examples of the negative electrode active material include graphite and Li ₄ Ti ₅ O ₁₂ .

  The particle diameter of the active material particles used in the present invention is not particularly limited, and those having an arbitrary size can be appropriately selected and used. In particular, according to the present invention in which active material particles having a small particle diameter are used, the total amount of the surface area of the active material particles in the electrode active material layer can be increased, and lithium in one active material particle can be increased. Since the moving distance can be shortened, the input / output characteristics can be dramatically improved. Therefore, when a higher input / output characteristic is required, it is desirable to select one having a small particle size. Specifically, the particle diameter of the active material particles to be used is preferably less than 10 μm, more preferably 5 μm or less, and particularly preferably 1 μm or less. In a conventional slurry-like electrode active material layer forming liquid using a resin binder, when the active material particle diameter used is less than 10 μm, the coating suitability tends to be poor, and when it is 5 μm or less, the formation is performed. The fluidity of the liquid is remarkably deteriorated, making it difficult to apply to mass production equipment such as a printing press. Further, if it is 1 μm or less, it tends to be difficult to disperse the active material particles in the forming liquid. On the other hand, when manufacturing this invention, since the above problems are avoided, the particle diameter of an active material particle can be selected arbitrarily. The particle size of the active material particles shown in the present invention and the present specification is an average particle size (volume median particle size: D50) measured by laser diffraction / scattering particle size distribution measurement.

The particle diameter of the active material particles contained in the electrode active material layer is a plurality of particle sizes arbitrarily selected from image observation results using image analysis type particle size distribution measurement software (manufactured by Mount Tech Co., Ltd., MAC VIEW). For example, it can be obtained by measuring the longest diameter of about 10 particles) and calculating the average value.
The use of active material particles is very advantageous and desirable. From the above viewpoint, in the present invention, the particle diameter of the active material particles is further selected to be 500 nm or less, more preferably 100 nm or less. By selecting a particle having a smaller particle diameter, the total surface area of the active material particles per unit weight of the electrode active material layer is increased, and the movement distance of lithium ions in one particle is decreased. As a result, the input / output characteristics are expected to be improved.

Metal oxide:
The metal oxide contained in the electrode active material layer exhibits a lithium ion insertion / release reaction, and may be a compound having an oxygen element bonded to a metal element, as long as these conditions are satisfied. The oxide is not particularly limited as long as it is an oxide of an element generally understood as a metal. More specifically, the metal oxide includes Li, Be, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Cs, Ba, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, One metal oxide of metal elements such as Tl, Pb, Bi, Fr, Ra, and Ce, or a composite metal oxide containing two or more metal elements can be used. The metal oxide in the present invention is desirable because it can be suitably used as an electrode plate of a lithium ion secondary battery by selecting a lithium composite oxide. In particular, when the metal oxide is a composite oxide of at least one metal selected from cobalt, nickel, manganese, iron, and titanium, lithium ion secondary battery Since a suitable electrode plate can be provided, it is preferable. More specifically, in the electrode active material layer in the electrode plate for a lithium ion secondary battery, the metal oxide can act as a binder and can also act as an active material. In addition, an electrode plate having an increased electrode capacity can be provided, which is preferable.

The metal element oxides listed above are metal oxides in which oxygen is bonded to any one of the above metal elements, or a composite metal containing two or more metal elements selected from the above metal elements Any of oxides may be used. In addition, it is a complex metal oxide containing two or more metal elements, and examples of the metal oxide in the positive electrode plate of the present invention include LiCoO ₂ , LiMn ₂ O ₄ , LiNiO ₂ , LiFeO ₂ , _{LiTiO 2, LiFePO 4, LiMnPO 4} , V 2 O 5, Li etc. ₄ Ti _{5 O 12} and the like. Similarly, examples of the metal oxide in the negative electrode plate of the present invention include Li ₄ Ti ₅ O ₁₂ and SiO ₂ . As illustrated above, the metal oxide in the present invention includes a metal element-containing phosphate compound.

  As exemplified above, the metal oxide in the present invention is a metal oxide exhibiting a lithium ion insertion / release reaction, and can also exhibit an action as an active material. From the viewpoint of the combination of the active material particles and the metal oxide that is the binding material for fixing the active material particles on the current collector, the combination of the positive electrode active material particles and the metal oxide that can be the positive electrode active material, or A combination of negative electrode active material particles and a metal oxide that can be a negative electrode active material is preferable.

  In particular, the metal oxide material constituting the positive electrode active material particles and the metal oxide as the binder material are the same compound, the metal oxide material constituting the negative electrode active material particles, The embodiment in which the metal oxide as the electrodeposition material is the same compound is very preferable from the viewpoint of increasing the electrode capacity. In particular, an embodiment in which the active material particles are lithium manganate particles and the binder material is also lithium manganate is desirable because the input / output characteristics are extremely improved. That is, a device operated using a battery has a voltage standard for each device. On the other hand, the electrode plate in the battery also has a unique potential (potential difference), and the potential is mainly determined by the potential of the active material contained in the electrode active material layer. Here, in the present invention, active material particles and a metal oxide (binding material) that can be an active material exist in the electrode active material layer. And the aspect in which the active material particle | grains and the said metal oxide are the same compounds also has the same electric potential. As a result, the metal oxide also participates in and out of lithium ions as an active material during charging / discharging like the active material particles, and the electrode capacity is substantially increased. On the other hand, the aspect in which the active material particles and the metal oxide are different compounds, and therefore the potential is also different, depends on the potential of the metal oxide and the voltage standard of the device in which the battery is used. May or may not act as an active material.

  In the present invention, the fact that the active material particles and the metal oxide as the binder are the same compound means that both are compounds having the same composition. At this time, the composition ratios shown in the chemical composition of the active material particles and the metal oxide are not only completely the same, but may be different within a range not departing from the gist of the present invention. Further, even when any element or both of the compound that is the active material particle and the compound that is the metal oxide are doped to an extent that does not depart from the spirit of the present invention, both compounds are the same. I can understand.

  In addition, as another method for determining that the active material particles and the metal oxide are the same compound by another means other than the analysis of the chemical composition, the crystal structure of the compound may be confirmed. That is, when a compound that is an active material particle and a compound that is a metal oxide are observed with a transmission electron microscope and the crystal structures of the two compounds are the same, both can determine the same compound. . Here, the same crystal structure means that the crystal structure is included in the same crystal phase. In other words, when the active material particles and the metal oxide are not the same, the crystal structures of the two are located in different crystal phases, and the narrowly defined identity based on the difference in the contrast of the crystal lattices. Not intended.

  For example, in the battery manufactured using the electrode plate of the present invention, an example in which the potential of the active material particles is 3.7 V and the potential of the metal oxide as the binding material is 4.5 V is described. When the battery is used in a device having a voltage standard of 3.7 V, the metal oxide does not reach a voltage indicating insertion / extraction of lithium ions, so that the metal oxide does not contribute to charging / discharging (that is, Does not act as an active material). On the other hand, in a battery manufactured using the electrode plate of the present invention, an example in which the potential of the active material particles is 3.7 V and the potential of the metal oxide as the binding material is 3.4 V is shown. When the battery is used in a device having a voltage standard of 3.7 V, the metal oxide exhibits insertion / extraction of lithium ions and contributes to charge / discharge (that is, acts as an active material). However, in the latter example, power loss is generated by the difference between the potential of the active material particles and the potential of the metal oxide. Therefore, from the viewpoint of increasing the discharge capacity of the battery (in this specification, the discharge capacity of the battery is also simply referred to as “battery capacity”), the metal oxide that is the binding material in the electrode plate of the present invention is lithium ion. A metal oxide that exhibits an insertion / release reaction and is preferably a metal oxide that exhibits a potential equal to or lower than that of the active material particles, and more preferably a metal oxide that exhibits a potential equal to that of the active material particles.

  In addition, as described above, the binding material that functions as an active material when used as a battery can increase the initial charge / discharge efficiency of the battery in addition to the effect of increasing the battery capacity. It was discovered by the inventors' extensive studies. Here, in general, there is a problem of reduction in initial charge / discharge efficiency in a lithium ion secondary battery. That is, when the charge capacity in the initial charge is 100%, there is a problem that the discharge capacity is reduced to less than 100% in the subsequent discharge. In some cases, the discharge capacity decreased below 95%. In general, during initial charging, a part of the lithium ions transferred from the positive electrode active material particles to the negative electrode active material particles is lost on the surface of the negative electrode active material particles. It is considered that 100% of lithium ions cannot be provided from the negative electrode active material particles to the positive electrode active material particles.

  On the other hand, when attention is paid to one active material particle contained in the electrode active material layer in the present invention, as one aspect of the present invention, the metal oxide as the binding material has at least the surface of the active material particle. Some may be covered. At this time, the binder may be present in a state having an exposed surface that can come into contact with the non-aqueous electrolyte. This is in contact with the binding material, a part of which is exposed so as to be in contact with the non-aqueous electrolyte, and other active material particles, a conductive material, a current collector, etc. It does not include a binding material that covers only a part of the surface of one active material particle. When a battery using the electrode plate of the present invention is operated, a binder material that covers at least a part of the surface of the active material particles and has an exposed surface that can come into contact with the non-aqueous electrolyte is an active material. Prior to the material particles or in parallel with the active material particles, a lithium insertion / extraction reaction can also occur in the binder material.

The electrode plate of the present invention is a coating layer for covering a plurality of active material particles, covering at least a part of the surface of the active material particles, or further having an exposed surface that can come into contact with the non-aqueous electrolyte. The present inventors infer that when the binding material acting as an active material can compensate for lithium ions lost during charging by the binding material. In order to confirm such a lithium ion supplementation effect, the following examples and reference examples can be implemented. That is, for the electrode plate of the present invention, the binder material is also converted as an active material, and the amount of active material per volume in the electrode active material layer is designed to be Xg / cm ³ . On the other hand, for the electrode plate of the reference example, the amount of active material per volume in a conventional electrode active material layer that does not include a binder that is a metal oxide is designed to be Xg / cm ³ . When comparing the above examples and the above reference examples, it can be seen that the electrode plate of the invention has higher initial charge / discharge efficiency. From this, it is understood that the improvement of the initial charge / discharge efficiency in the above-described examples is due to the presence of the binding material that exhibits the action of the active material. It is unclear why the binding material covers the surface of the active material particles, so that such an effect is exhibited. Since there is a part that covers the active material particles in the form of a thin film, it is very easy for lithium ions to enter and exit both the non-aqueous electrolyte side and the active material particle side that comes into contact with it. I guess I can make up for it. The electrode plate of the present invention is capable of improving the initial charge / discharge efficiency as compared to a conventional electrode plate using only a resin binder containing approximately the same amount of active material particles per unit area, preferably The initial discharge capacity is 100%, and the subsequent discharge capacity can be 95% or more, more preferably 98% or more.

  In addition, the example of the metal oxide described above does not limit the metal oxide in this invention at all. In the present invention, the metal oxide that can act as a binder for the active material particles on the current collector is a metal oxide that exhibits a lithium ion insertion / release reaction. Any material can be used as long as it can be fixed on the body.

  In the present invention, it can be confirmed by an electrochemical measurement (cyclic voltammetry) method whether or not the metal oxide as the binding substance exhibits a lithium ion insertion / elimination reaction.

Specifically, the electrode potential is set and measurement is performed in an appropriate voltage range of the metal oxide. For example, if the metal oxide is LiMn ₂ O ₄ , the operation of sweeping from 3.0 V to 4.3 V and then returning to 3.0 V again is repeated about three times. The scanning speed is preferably 1 mV / sec. For example, if the metal oxide is LiMn ₂ O ₄ , in the cyclic voltammogram, an oxidation peak corresponding to the Li elimination reaction of LiMn ₂ O ₄ appears in the vicinity of about 3.9 V, and Li in the vicinity of about 4.1 V. A reduction peak corresponding to the insertion reaction appears. The appearance of the peak confirms the insertion / extraction reaction of LiMn ₂ O ₄ lithium ions. FIG. 2 shows the second cycle result in the cyclic voltammogram when LiMn ₂ O ₄ is used. The appropriate voltage range means a voltage range in which the presence or absence of a peak indicating insertion / extraction of lithium ions in the metal oxide used in the test can be confirmed in the cyclic voltammetry test.

  On the other hand, when a cyclic voltammetry test is similarly performed using iron oxide as an example of a metal oxide that does not show insertion / extraction reaction of lithium ions, no peak is detected in the cyclic voltammogram. FIG. 3 shows the results of the second cycle in the cyclic voltammogram when using iron oxide.

  In producing the electrode plate of the present invention, the presence or absence of a lithium ion insertion / release reaction of a metal oxide that is expected to be contained in the electrode active material layer can be confirmed as described above. Therefore, after confirming in advance, a metal oxide that exhibits a lithium ion insertion / release reaction is determined as a binder in the electrode active material layer. On the other hand, whether or not a metal oxide showing a lithium ion insertion / release reaction is contained in the electrode active material layer in the electrode plate that has already been completed can be confirmed as follows, for example. That is, it is possible to estimate what kind of metal oxide is contained in the sample by cutting the electrode active material layer to prepare a sample and performing composition analysis of the sample. Then, by forming a coating film made of the estimated metal oxide on a substrate such as glass and subjecting it to a cyclic voltammetry test, the metal oxide does not show a lithium ion insertion / desorption reaction. Can be confirmed. Alternatively, the electrode active material layer in the already completed electrode plate is observed with a transmission electron microscope, and the crystal lattice of the metal oxide as the binding material is the same as the crystal lattice of the compound known as a conventionally known active material If so, it can be determined that the metal oxide as the binding substance is a metal oxide exhibiting a lithium ion insertion / release reaction.

  In the present invention, the mixing ratio of the active material particles and the metal oxide in the electrode active material layer is not particularly specified, the type and size of the active material particles used, the type of metal oxide, the function required for the electrode, etc. Can be determined as appropriate. However, since the metal oxide in the present invention exhibits a lithium ion insertion / release reaction as described above, it not only plays a role as a binder for fixing the active material particles on the current collector. It can also play a role as an active material.

(Other materials)
The electrode active material layer can be composed only of the above-described active material particles and a metal oxide as a binder, but further additives are contained within a range not departing from the gist of the present invention. Also good. For example, the electrode plate of the present invention can exhibit good conductivity without using a conductive material, but when better conductivity is desired or the content of active material particles is increased. For example, it is desirable to use a conductive material.

  As the conductive material, those usually used for electrode plates for non-aqueous electrolyte secondary batteries can be used, and examples thereof include carbon materials such as acetylene black and carbon black such as ketjen black. It is not limited to. The average particle size of the conductive material is preferably about 20 nm to 50 nm. Carbon fiber (VGCF) is known as a different conductive material. The average particle diameter is obtained by an arithmetic average obtained from actual measurement using an electron microscope, as in the method of measuring the particle diameter of the active material particles.

  In the case where the conductive material is contained in the electrode active material layer, the content is not particularly limited, but in general, with respect to 100 parts by weight of the active material particles or 100 parts by weight of the total amount of the active material particles and the binding material. Thus, it is desirable that the ratio of the conductive material be 5 parts by weight or more and 20 parts by weight or less.

  In the present invention, the active material particles can be fixed on the current collector without using a resin binder, but this prohibits the resin component from being contained in the electrode active material layer. It is not the purpose. For example, when assembling a battery using an electrode plate, it is necessary to immerse the electrolyte into the pores of the electrode. At this time, in order to improve the permeability of the electrolyte, a resin is contained in the electrode active material layer. The component may be contained in an amount of 1 to 10%. Thus, if necessary, a small amount of resin material may be contained in the electrode active material layer in the present invention. Alternatively, as the binder, in addition to the metal oxide, a resin binder may be contained in the electrode active material layer.

(DC resistance measurement)
In the present invention, the input / output characteristics of the electrode plate can be evaluated by measuring the DC resistance value (Ω) of the manufactured electrode plate. That is, when the DC resistance value of the electrode plate is low, it means that the electrical conductive path is good, and as a result, it can be understood that the input / output characteristics are improved. The DC resistance value can be measured by the following method. That is, the measurement of the direct current resistance value is calculated as follows using a test cell. When a discharge test is performed at two types of discharge rates (for example, discharge rates 1C and 5C), a voltage value (mV) 10 seconds after the start of discharge is measured. For example, the voltage value (V1) (mV) when the discharge test is performed under the condition of the discharge rate 1C, and the voltage 10 seconds after the start of the discharge when the discharge test is performed under the condition of the discharge rate 5C. The value (V5) (mV) is measured. Based on these measured values (V1, V5) and the constant current values (I1, I5) (mA) corresponding to the discharge rates 1C, 5C, the direct current resistance value (Ω) is expressed by the following equation (1). Calculated.

[Method for producing electrode plate for non-aqueous electrolyte secondary battery]
Next, a method for producing the electrode plate for a non-aqueous electrolyte secondary battery of the present invention (hereinafter sometimes simply referred to as “the production method of the present invention”) will be described. In the production method of the present invention, first, an electrode active material layer formation comprising a metal element-containing compound that becomes a precursor of a metal oxide as a binder, active material particles, and a shape change agent, or further an optional additive. Prepare the solution. The production method of the present invention includes an application step of applying the electrode active material layer forming liquid to a desired region of the current collector surface to form a coating film, and an electrode active material layer forming the electrode active material layer from the coating film. And a material layer forming step.

In the electrode active material layer forming step, the solvent contained in the coating film is removed and a metal element-containing compound contained in the coating film is reacted to generate a metal oxide. It may be a step of forming an electrode active material layer containing the metal oxide and the active material particles on the current collector by fixing the active material particles on the current collector.

  Alternatively, in the electrode active material layer forming step in the present invention, an optional step is provided between the coating step and the electrode active material layer forming step, and after removing the solvent in the coating film, the electrode active material layer forming step May be implemented. That is, in the electrode active material layer forming step, a metal element-containing compound contained in the coating film from which the solvent has been removed is reacted to generate a metal oxide, and the active material particles are collected by the metal oxide. It may be a step of forming an electrode active material layer containing the metal oxide and the active material particles on the current collector by being fixed on the current collector.

  In the production method of the present invention, when producing a positive electrode plate, the positive electrode active material layer and the positive electrode active material layer are formed in the electrode active material layer forming liquid in order to form a positive electrode active material layer on the current collector. When a negative electrode plate is produced by adding a metal element-containing compound suitable for the electrode active material layer, the negative electrode active material particle is formed in the electrode active material layer forming liquid in order to form a negative electrode active material layer on the current collector. And a metal element-containing compound suitable for this is added. However, in the manufacturing method of the present invention, “positive electrode” and “negative electrode” may be collectively referred to as “electrode”.

  Unlike the conventional slurry-like electrode active material layer forming liquid using a resin binder, the metal element-containing compound and the active material particles used in the method for producing an electrode plate for a non-aqueous electrolyte secondary battery of the present invention In addition, the electrode active material layer forming liquid prepared containing the shape change agent has a viscosity that can maintain good coatability on the current collector regardless of the particle size of the active material particles contained. It is. Therefore, in the conventional electrode active material layer forming liquid, the active material particles having a small particle diameter, which has been difficult to use due to a significant improvement in viscosity, are used in the method for producing an electrode plate for a non-aqueous electrolyte secondary battery of the present invention. It can be used now. In addition, the method for producing an electrode plate for a non-aqueous electrolyte secondary battery according to the present invention can be applied to a desired thickness because the electrode active material layer forming liquid has good applicability to the current collector. Thus, the electrode active material layer can be made thin.

  Examples of the electrode active material layer forming step include, but are not limited to, a heating step, a reduced pressure drying step, a reduced pressure heating step, or a combination thereof, and an electrode active material applied on a current collector. It may be a step of implementing means capable of forming a coating film formed by the layer forming solution as an electrode active material layer. For example, the electrode active material layer forming step may include two or more means such as a means for removing the solvent contained in the coating film and then a means for reacting the metal element-containing compound. .

  When the electrode active material layer forming step is a heating step for performing a heating means, the production method of the present invention applies the electrode active material layer forming solution in which the metal element-containing compound is dissolved onto the current collector. Then, the metal element-containing compound can be heated and decomposed at a temperature equal to or higher than the thermal decomposition start temperature, and the metal element contained therein can be oxidized to produce a metal oxide exhibiting a lithium insertion / elimination reaction. In the electrode active material layer forming step, the metal oxide produced on the current collector is coated on the current collector so as to embrace the active material particles contained in the solution. It can be fixed on the current collector. The active material particles and the conductive material particles contained in the electrode active material layer forming liquid are fixed in a state in which the direct contact between the particles is well maintained as shown in the fixing mode 2 in addition to the fixing mode 1. Embodiments to be included. As described above, the factors that enable the fixed state as shown in the fixing modes 1 and 2 are that the metal element-containing compound is dissolved in the solvent and the active material particles in the manufacturing method of the present invention. When forming the electrode active material layer by applying the electrode active material layer forming liquid mixed with the electrode to form the electrode active material layer, the solvent is removed by means such as heating, and the generated metal oxide (binding material) It is presumed that the particles are generated between the particles or around the contact portion where the particles are in direct contact with each other. As a result, the manufacturing method of the present invention can manufacture an electrode plate that has good conductivity and can keep electric resistance low. In addition, in the manufacturing method of this invention, the metal element containing compound contained in an electrode active material layer forming solution is called a metal element containing compound including the state melt | dissolved in the solvent.

Active material particles:
Since the active material particles contained in the electrode active material layer forming liquid are the same as the positive electrode active material particles or the negative electrode active material particles already described above, the description thereof is omitted here. The electrode active material layer forming liquid used in the present invention is a case where active material particles having a small average particle diameter are used as compared with an electrode active material layer forming liquid using a conventional resin binder. The viscosity can be easily adjusted. In particular, the electrode active material layer forming liquid used in the production method of the present invention has a viscosity that reduces applicability even when the active material particles have a particle size of 10 μm or less, and even 1 μm or less. It has a desirable feature that no increase in the level of Therefore, a desired size can be selected for the particle diameter of the active material particles used.

Metal element-containing compounds:
The metal element-containing compound dissolved in the electrode active material layer forming liquid is contained in the electrode active material layer, and the active material particles are fixed to each other as a binder, and the active material particles are placed on the current collector. It is a metal oxide precursor that is fixed and exhibits lithium ion insertion / release reaction. Therefore, the metal element-containing compound can be applied to the substrate in a state dissolved in a solution, and can generate the metal oxide described above when heated at a temperature equal to or higher than the thermal decomposition start temperature. Good. Whether or not the metal oxide produced from the metal element-containing compound to be used exhibits a lithium ion insertion / release reaction is determined by applying a solution containing the metal element-containing compound on the substrate in a preliminary experiment. Is heated to form a metal oxide, which can be confirmed by the cyclic voltammetry method described above.

  For example, as an example of the metal element-containing compound, one or more of a lithium element-containing compound and a metal element-containing compound containing any metal element selected from cobalt, nickel, manganese, iron or titanium The combination of is mentioned. Further, the metal element-containing compound used in the present invention may be an inorganic metal element-containing compound that does not contain carbon in the compound, or an organic metal constituted by containing carbon in the compound. It may be an element-containing compound. In the present invention and the present specification, the inorganic metal element-containing compound and the organic metal-containing compound are sometimes collectively referred to as a metal element-containing compound.

  Examples of the metal element-containing compound include chloride, nitrate, sulfate, perchlorate, acetate, phosphate, bromate, carbonate, etc. of other metal elements such as lithium element or cobalt. it can. Among them, in the present invention, chloride, nitrate, and acetate are preferably used because they are easily available as general-purpose products. In particular, nitrate is preferably used because it has good film forming properties for a wide variety of current collectors. It is preferable to use at least a lithium salt as the metal element-containing compound because it facilitates the production of an electrode plate for a lithium ion secondary battery. In particular, as the metal element-containing compound, by using one or more metal salts containing a metal selected from cobalt, nickel, manganese, iron and titanium, and a lithium salt, a lithium composite metal oxide Can be produced in the electrode active material layer. The lithium composite oxide can act as a binder in the electrode active material layer of the electrode plate for a lithium ion secondary battery, and can also act as an active material. This is preferable because it is easy to manufacture an electrode plate having an increased capacity.

For example, as a metal element-containing compound for generating LiCoO ₂ as a metal oxide on a current collector, a Li element-containing compound and a Co element-containing compound can be used in combination as main raw materials, and further necessary Depending on the case, other raw materials may be used in combination with the main raw material. Examples of the Li element-containing compound include lithium citrate tetrahydrate, lithium perchlorate trihydrate, lithium acetate dihydrate, lithium nitrate, lithium carbonate, and lithium phosphate. Examples of the Co element-containing compound include cobalt (II) chloride hexahydrate, cobalt (II) formate dihydrate, cobalt (III) acetylacetonate, cobalt (II) acetylacetonate dihydrate, and acetic acid. Cobalt (II) tetrahydrate, cobalt (II) oxalate dihydrate, cobalt (II) nitrate hexahydrate, cobalt (II) ammonium chloride hexahydrate, sodium cobalt (III) nitrite, carbonic acid Examples thereof include cobalt and cobalt (II) sulfate heptahydrate. The combination ratio (Li: Co = X: 1) of the Li element-containing compound and the Co element-containing compound used as the main raw material is not particularly limited, but is preferably 1 ≦ X <2, and preferably 1 ≦ X ≦ 1. 2 is more preferable.

Further, for example, as a metal element-containing compound for generating LiNiO ₂ as a metal oxide on a current collector, a Li element-containing compound and a Ni element-containing compound can be used in combination as main raw materials, If necessary, other raw materials can be used in combination with the main raw material. Examples of the Li element-containing compound are the same as in the case of producing LiCoO ₂ described above. Examples of the Ni element-containing compound include nickel chloride (II) hexahydrate and nickel acetate (II) tetrahydrate. , Nickel (II) perchlorate hexahydrate, nickel (II) bromide trihydrate, nickel (II) nitrate hexahydrate, nickel (II) acetylacetonate dihydrate, hypophosphorous acid Examples thereof include nickel (II) acid hexahydrate, nickel carbonate, and nickel (II) sulfate hexahydrate. The combination ratio (Li: Ni = X: 1) of the Li element-containing compound and Ni element-containing compound used as the main raw material is not particularly limited, but is preferably 1 ≦ X <2, and preferably 1 ≦ X ≦ 1. 2 is more preferable.

Also, for example, as a metal element-containing compound for generating LiMn ₂ O ₄ as a metal oxide on a current collector, a Li element-containing compound and a Mn element-containing compound can be used in combination as main raw materials, If necessary, other raw materials can be used in combination with the main raw material. Examples of the Li element-containing compound are the same as in the case of producing LiCoO ₂ described above, and examples of the Mn element-containing compound include manganese acetate (III) dihydrate, manganese nitrate (II) hexahydrate. Products, manganese (II) sulfate pentahydrate, manganese (II) oxalate dihydrate, manganese carbonate, manganese (III) acetylacetonate and the like. The combination ratio (Li: Mn = X: 1) of the Li element-containing compound and the Mn element-containing compound used as the main raw material is not particularly limited, but is preferably 0.5 ≦ X <1, 0.5 ≦ More preferably, X ≦ 0.6.

Further, for example, as a metal element-containing compound for generating LiFeO ₂ as a metal oxide on a current collector, a Li element-containing compound and a Fe element-containing compound can be used in combination as main raw materials, and further necessary Depending on the case, other raw materials may be used in combination with the main raw material. Examples of the Li element-containing compound are the same as in the case of producing LiCoO ₂ described above. Examples of the Fe element-containing compound include iron chloride (II) tetrahydrate, iron (III) citrate, and acetic acid. Examples include iron (II), iron (II) oxalate dihydrate, iron (III) nitrate nonahydrate, iron (II) lactate trihydrate, and iron (II) sulfate heptahydrate. . The combination ratio (Li: Fe = X: 1) of the Li element-containing compound and the Fe element-containing compound used as the main raw material is not particularly limited, but is preferably 1 ≦ X <2, and preferably 1 ≦ X ≦ 1. 2 is more preferable.

Further, for example, as a metal element-containing compound for generating Li ₄ Ti ₅ O ₁₂ as a metal oxide on a current collector, a Li element-containing compound and a Ti element-containing compound can be used in combination as main raw materials. Furthermore, if necessary, other raw materials can be used in combination with the main raw material. Examples of the Li element-containing compound are the same as in the case of producing LiCoO ₂ described above, and examples of the Ti element-containing compound include titanium tetrachloride, a titanium chelating agent, and titanium acetylacetonate. The combination ratio (Li: Ti = X: 1) of the Li element-containing compound and the Ti element-containing compound used as the main raw material is not particularly limited, but is preferably 0.8 ≦ X <2, and 0.8 ≦ More preferably, X ≦ 1.0.

  In the electrode active material layer forming liquid described above, the ratio of the total amount of one or more metal element-containing compounds added in the solvent is 0.01 to 5 mol / L, particularly 0.1 to 5 mol / L. 2 mol / L is preferred. When the concentration is 0.01 mol / L or more, the current collector and the electrode active material layer generated on the surface of the current collector are satisfactorily adhered, and the active material particles are fixed. Further, when the concentration is 5 mol / L or less, the electrode active material layer forming liquid can maintain a good viscosity enough to be applied to the current collector surface, and a uniform coating film is formed. Is done.

Shape change agent:
As one of means for forming the metal oxide generated in the electrode active material layer forming step as a coating layer covering a plurality of active material particles, and forming a plurality of protrusions on the surface of the coating layer And a method of adding a shape-changing agent to the electrode active material layer forming liquid. As the shape change agent, a coupling agent is preferable, and a silane coupling agent, titanate coupling agent, or aluminum coupling agent is particularly preferable. By using the shape change agent, it is easy to obtain a form in which the surface of the coating layer opposite to the active material particles is contracted and raised, which is one embodiment of the present invention.

  Examples of the silane coupling agent include γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, and β- (3,4-epoxycyclohexyl) ethyl. Trimethoxysilane, γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane hydrochloride, γ-glycidoxy Propyltrimethoxysilane, aminosilane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltriacetoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilazane, γ-anilinopropyltrimethoxy Sisilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, octadecyldimethyl [3- (trimethoxysilyl) propyl] ammonium chloride, γ-chloropropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxy Examples include silane, methyltrichlorosilane, dimethyldichlorosilane, and trimethylchlorosilane.

  Examples of the titanate coupling agent include isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctylpyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite). Phyto) titanate, tetra (2,2-diallyloxymethyl) bis (di-tridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, isopropyl Dimethacrylisostearoyl titanate, isopropylisostearoyl diacryl titanate DOO, isopropyl tri (dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, isopropyl tri (N- amidoethyl-aminoethyl) titanate, dicumyl phenyloxy acetate titanate, diisostearoyl ethylene titanate.

  Examples of the aluminum coupling agent include acetoalkoxyaluminum diisopropylate.

(Other additives)
In addition to the active material particles, the metal element-containing compound, and the shape change agent described above, the electrode active material layer forming liquid includes a conductive material, a dispersant, a plasticizer, or a range that does not depart from the spirit of the present invention. Other additives may be added. As the other additives except the conductive material, the dispersant, and the plasticizer, the same materials as described in the description of the electrode active material layer of the present invention can be used.

  When the conductive material is added to the electrode active material layer forming liquid, the active material particles generated on the current collector surface, or the active material particles and the total amount of metal oxides scheduled to be formed are 100 parts by weight. In addition, the addition amount of the conductive material is desirably 5 to 20 parts by weight. In addition, the above is not the meaning which excludes adding a conductive material exceeding 20 weight.

The dispersant is used to satisfactorily disperse the active material particles and the conductive agent added to the electrode active material layer forming liquid in the forming liquid. Examples of the dispersant include aromatic solvents such as toluene, ketone solvents such as amines, solvents such as esters, ether solvents, amides, and water.

  The plasticizer is added to the electrode active material layer forming liquid in order to ensure the so-called pot life for ensuring the performance of the electrode active material layer forming liquid as an ink. Examples of the plasticizer include phthalic acid esters such as dioctyl phthalate, diheptyl phthalate and dibutyl phthalate, organic acid esters such as adipic acid ester, glyceric acid ester and citrate ester, and phosphorous such as trioctyl phosphate. Examples include acid esters, liquid paraffin, solid wax, mineral oil, and the like. These may be used alone or as a mixture.

(solvent)
The solvent used for preparing the electrode active material layer forming liquid is not particularly limited. For example, water or a lower alcohol having a total carbon number of 5 or less, such as methanol, ethanol, isopropyl alcohol, propanol, and butanol. And diketones such as acetylacetone, diacetyl and benzoylacetone, ketoesters such as ethyl acetoacetate, ethyl pyruvate, ethyl benzoylacetate and ethyl benzoylformate, toluene, and a mixed solvent thereof.

  In addition, the electrode active material layer forming liquid requires active material particles, metal oxides, or other additives such as a conductive material as required in the electrode active material layer to be formed on the current collector. These amounts are determined in consideration of being included in the amounts. At that time, the ratio of the solute added to the solvent (that is, the active material particles, the metal element-containing compound, and the optional additive) depends on the coating property on the current collector and the electrode active material layer forming step in the coating step. Adjust as appropriate in consideration of removal of the solvent. Generally, when the electrode active material layer forming liquid is 100% by weight, the total amount of solutes contained is adjusted to be 30 to 70% by weight.

  Next, the electrode active material layer forming liquid prepared as described above is applied onto a current collector to form a coating film. The current collector used in the production method of the present invention is the same as the current collector used in the electrode plate for a non-aqueous electrolyte secondary battery, and the description thereof is omitted here.

  In the coating step in the production method of the present invention, a known coating method can be appropriately selected and implemented as a solution coating method. For example, the electrode active material layer forming liquid can be applied to any region of the current collector surface to form a coating film by printing, spin coating, dip coating, bar coating, spray coating, or the like. In addition, when the current collector surface is porous, has a large number of irregularities, or has a three-dimensional structure, the coating method is other than the above method, for example, a manual coating method. Is also possible. Note that the current collector used in the present invention is preferable because corona treatment, oxygen plasma treatment, and the like can be performed in advance as necessary to further improve the film forming property of the electrode active material layer.

  The amount of the electrode active material layer forming liquid applied to the current collector can be arbitrarily determined according to the application of the electrode plate to be produced. Since the electrode active material layer in the present invention can be formed very thin as described above, when it is desired to reduce the thickness, the final electrode active material layer has a thickness of 300 nm to 150 μm, particularly 500 nm. You may apply | coat thinly so that it may be set to about ~ 100 micrometers. As described above, a coating film for forming an electrode active material layer containing a metal element-containing compound that is a precursor of a metal oxide that is a binder is formed by applying an electrode layer forming solution to a substrate. The

  A pressing step may be further performed between the coating step and the electrode active material layer forming step or after the electrode active material layer forming step. The said press process can be implemented by drying the said coating film for electrode active material layer formation formed on the electrical power collector as needed, removing a solvent, and pressing it after that. Therefore, when performing an electrode active material layer formation process after a press process, a part or all of the solvent in a coating film may be removed beforehand before this electrode active material layer formation process. The pressing method can be carried out in the same manner as the press performed by applying a slurry-like electrode active material layer forming liquid containing a conventional resin binder on the current collector and drying it. However, it is not limited to this. Thus, the manufacturing method of the present invention can adjust the porosity of the electrode active material layer in the finally manufactured electrode plate and increase the energy density per volume by performing the pressing step. .

  Next, the electrode active material layer forming step for forming the electrode active material layer from the coating film formed in the coating step will be described by taking a heating step for heating the coating film as an example. This heating step is carried out for the purpose of thermally decomposing and oxidizing the metal element-containing compound present in the coating film, and removing the solvent contained in the coating film (but before the heating step) When carrying out the pressing step, the solvent is substantially removed beforehand by drying before pressing). The heating method is not particularly limited as long as it is a heating method or a heating apparatus capable of heating the coating film at a heating temperature described later, and can be appropriately selected and carried out. Specific examples include a method of using a hot plate, an oven, a heating furnace, an infrared heater, a halogen heater, a hot air blower, or the like, or a combination of two or more. When the current collector to be used is planar, it is preferable to use a hot plate or the like for the heating step. In addition, when heating using a hot plate, it is preferable to install and heat the coating film surface side in a direction not in contact with the hot plate surface. The heating temperature varies depending on the type of the metal element-containing compound used. However, the metal element-containing compound is favorably thermally decomposed by heating the coating film in a temperature range of 150 ° C. to 800 ° C. An oxide is produced. The generated metal oxide is understood to be a crystalline metal oxide because it exhibits a lithium ion insertion / release reaction.

  Here, generally, when producing a crystalline metal oxide, it is necessary to heat the coating film at a temperature of at least about 800 ° C. or higher. On the other hand, in the production method of the present invention, the crystalline metal oxide is generated even at a low heating temperature of 700 ° C. or lower, further 600 ° C. or lower, particularly 400 ° C. or lower. This is one of the characteristic points of the manufacturing method. Note that the crystalline metal oxide includes a microcrystalline state. According to the study by the present inventors, the coating step and the heating step in the production method of the present invention were carried out using a test solution prepared in the same manner as the electrode active material layer forming liquid except that the active material particles were not included. It was also found that a crystalline metal oxide (hereinafter referred to as metal oxide A) exhibiting a lithium ion insertion / elimination reaction was produced even when carried out. In addition to this, when the electrode active material layer is formed on the current collector using the electrode active material layer forming liquid containing the active material particles, the binder contained in the electrode active material layer It was found that the metal oxide (hereinafter referred to as “metal oxide B” in this paragraph) exhibits a lithium ion insertion / release reaction and a discharge capacity (μAh) superior to that of the metal oxide A. . The discharge capacity (μAh) shown in the metal oxide B tends to be shown to a value very close to the theoretical value of the metal oxide B. The point that a metal oxide having such a high discharge capacity (that is, excellent crystallinity) can be produced at a heating temperature as low as 700 ° C. or less, further 600 ° C. or less, particularly 400 ° C. or less. This is a notable advantage of the production method of the present invention. The relationship between the heating temperature described above and the development of crystallinity of the metal oxide produced is estimated as follows. That is, since the active material particles are contained in the electrode active material layer forming liquid, the generated metal oxide follows the crystallinity of the active material particles, and is 700 ° C. or lower, further 600 ° C. In particular, it is presumed that lithium insertion / extraction reaction is possible even at a heating temperature of 400 ° C. or lower, and a highly crystalline metal oxide is obtained. In particular, when the chemical composition of the active material particles to be mixed with the generated metal oxide is the same, this follow-up action is assumed to be remarkable.

  The heating step is performed at a heating temperature of 400 ° C. or less, so that the selection range of the current collector is widened, and the electrode active material layer can be directly formed on various current collectors. Since various effects, such as the point that cost merit improves by having low temperature, are preferable.

  In addition, the heating temperature is preliminarily applied to a suitable substrate with a solution in which a metal element-containing compound to be used is dissolved and heated, and a film laminated on the substrate is scraped and used as a sample. By performing composition analysis and measuring the content ratio of the metal element and oxygen, it can be determined whether or not a metal oxide is formed. And when the metal oxide was produced | generated, it was confirmed that the used metal element containing compound was heated at the temperature more than thermal decomposition start temperature on a board | substrate. That is, in the present invention, the “thermal decomposition start temperature of the metal element-containing compound” can be understood as a temperature at which the metal element-containing compound is decomposed by heating and the oxidation of the metal element starts.

  In the heating step, when determining the heating temperature, it is desirable to further consider the heat resistance of the current collector, active material particles, conductive material, and the like used. For example, since the heat resistance of an aluminum foil generally used as a current collector for a positive electrode plate is around 660 ° C., the current collector may be damaged if the heating temperature exceeds 660 ° C. Therefore, the current collector, active material particles, etc. to be used are determined first, taking into account their heat resistance, taking into account their heat resistant temperature and thermal decomposition starting temperature, and selecting a metal element-containing compound. Also good. In the production method of the present invention, “heating temperature” means the highest temperature in the heating step. The heating mode in the heating step may be arbitrarily determined, for example, by gradually increasing the temperature, heating at a constant temperature, or heating at a stepped temperature.

  The electrode plate of the present invention may further contain a resin component in the electrode active material layer produced as described above. For example, the electrode active material layer may further contain a resin component by, for example, applying a resin mixed solution to the surface of the electrode active material layer or immersing an electrode plate in a resin mixed solution tank, A method of removing the solvent of the resin mixed solution impregnated in the electrode active material layer by infiltrating the gaps in the electrode active material layer and then drying, and leaving only the resin component inside the electrode active material layer. Can be mentioned. Thus, if it is the electrode plate of this invention which contains a resin component in an electrode active material layer, the bending tolerance of an electrode plate will improve by presence of a resin component, and it can improve a process characteristic. In particular, when the resin component is a conventionally used resin binder, the film adhesion of the electrode active material layer to the current collector can be further improved.

  As the resin material contained in the resin mixed solution, for example, a conventional resin binder such as PVDF, styrene butadiene rubber (SBR), carboxymethoxy cellulose (CMC), or those listed in the viscosity modifier are selected. However, the present invention is not limited to this. The resin material is appropriately selected to have a size that can penetrate into the voids in the electrode active material layer. Examples of the solvent for the resin mixture include lower alcohols having a total carbon number of 5 or less such as methanol, ethanol, isopropyl alcohol, propanol, and butanol, diketones such as acetylacetone, diacetyl, and benzoylacetone, ethyl acetoacetate, and pyrubin. Ketoesters such as ethyl acetate, ethyl benzoylacetate and ethyl benzoylformate, pyrrolidones such as N-methylpyrrolidone (NMP), toluene, a mixed solvent thereof, water, and the like can be used. Can be mixed to prepare a resin mixed solution.

  The amount of the resin component contained in the electrode active material layer is desirably adjusted to such an extent that the input / output performance of the electrode plate is not deteriorated. That is, when manufacturing the electrode plate of the present invention in which the resin material is contained in the electrode active material layer, the pore diameter or porosity specified in the present invention is adjusted to an amount that can be ensured.

[Nonaqueous electrolyte secondary battery]
In general, the non-aqueous electrolyte secondary battery of the present invention includes a positive electrode plate 50 in which an electrode active material layer 54 is provided on one surface side of a current collector 55, as illustrated in FIG. An electrode plate 10 in which the electrode active material layer 2 is provided on one side of the current collector 1 to be combined (that is, in FIG. 8, the electrode plate 10 is a negative electrode plate), and a polyethylene porous material therebetween. A separator 70 such as a film is provided. These are housed in the outer casings 81 and 82 and sealed and manufactured in a state where the outer casings 81 and 82 are filled with the non-aqueous electrolyte 90, thereby forming the non-aqueous electrolyte secondary battery 100. The

(Electrode plate)
The non-aqueous electrolyte secondary battery of the present invention is particularly characterized in that at least one of the positive electrode plate and the negative electrode plate uses the electrode plate for a non-aqueous electrolyte secondary battery of the present invention described above.

  In particular, conventionally, when the negative electrode plate is composed of a carbonaceous material, it has been common to add a large amount of conductive material to the positive electrode plate in order to increase the conductivity of the positive electrode plate accordingly. For this reason, the porosity of the positive electrode plate is lowered, and the permeability of the electrolytic solution is lowered, so that it is difficult to increase the output of the battery. However, since the electrode plate of the present invention is an electrode plate capable of high input / output, when this is used as a positive electrode plate, a large amount of conductive material is not used as in the prior art, or no conductive material is used at all. Good electrical conductivity and high input / output can be achieved.

  In addition, non-aqueous electrolyte secondary batteries do not insert and remove lithium ions, such as metallic lithium and its alloys, tin, silicon, and their alloys, rather than carbonaceous materials such as graphite, as the negative electrode active material used in the negative electrode plate. The aspect which comprises a negative electrode plate using the material which can be separated is also included. In such a battery, a nonaqueous electrolyte secondary battery can be produced by positively using the electrode plate of the present invention as a negative electrode.

  Moreover, a nonaqueous electrolyte secondary battery can also be comprised using the electrode plate of this invention for both a positive electrode plate and a negative electrode plate.

  In the nonaqueous electrolyte secondary battery of the present invention, when the electrode plate of the present invention is used in either the positive electrode plate or the negative electrode plate, the other electrode plate is used in the nonaqueous electrolyte secondary battery. The conventionally well-known electrode plate used can be used suitably.

  As a conventionally well-known positive electrode plate, in general, at least part of the current collector surface similar to the current collector used in the electrode plate of the present invention, positive electrode active material particles, conductive material, resin binder A positive electrode active material layered solution to which is added, etc. is applied, dried, and pressed as necessary.

  On the other hand, as a conventionally known negative electrode plate, a copper foil such as an electrolytic copper foil or a rolled copper foil having a thickness of about 5 to 50 μm is used as a current collector, and a negative electrode active material layer type is formed on at least a part of the current collector surface. What was formed by apply | coating a liquid, drying, and pressing as needed is used. In the negative electrode active material layered liquid, generally active material particles made of carbonaceous material such as natural graphite, artificial graphite, amorphous carbon, carbon black, or those obtained by adding different elements to these components, or Active material particles made of lithium ion insertion / desorption materials such as metallic lithium and alloys thereof, tin, silicon, and alloys thereof, and other additives such as resin binders and conductive materials as required It is common for agents to be mixed.

(Non-aqueous electrolyte)
The non-aqueous electrolyte used in the present invention is not particularly limited as long as it is generally used as a non-aqueous electrolyte for a non-aqueous electrolyte secondary battery, but a lithium salt is dissolved in an organic solvent. A non-aqueous electrolyte is preferably used.

Examples of the lithium salt include inorganic lithium salts such as LiClO ₄ , LiBF ₄ , LiPF ₆ , LiAsF ₆ , LiCl, and LiBr; LiB (C ₆ H ₅ ) ₄ , LiN (SO ₂ CF ₃ ) ₂ , LiC ( Organic compounds such as SO ₂ CF ₃ ) ₃ , LiOSO ₂ CF ₃ , LiOSO ₂ C ₂ F ₅ , LiOSO ₂ C ₄ F ₉ , LiOSO ₂ C ₅ F ₁₁ , LiOSO ₂ C ₆ F ₁₃ , and LiOSO ₂ C ₇ F ₁₅ Typical examples include lithium salts.

  Examples of the organic solvent used for dissolving the lithium salt include cyclic esters such as propylene carbonate and butylene carbonate, chain esters such as dimethyl carbonate and diethyl carbonate, cyclic ethers such as tetrahydrofuran and alkyltetrahydrofuran, and 1,2- Examples include, but are not limited to, chain ethers such as dimethoxyethane and 1,2-diethoxyethane.

  As the structure of the non-aqueous electrolyte secondary battery of the present invention produced using the positive electrode plate, the negative electrode plate, the separator, and the non-aqueous electrolyte solution, a conventionally known structure can be appropriately selected and employed. For example, the structure which winds a positive electrode plate and a negative electrode plate in the shape of a spiral via the separator like a polyethylene porous film, and accommodates in a battery container is mentioned. As another aspect, a structure may be employed in which a positive electrode plate and a negative electrode plate cut into a predetermined shape are stacked and fixed via a separator, and are accommodated in a battery container. In any structure, for example, after the positive electrode plate and the negative electrode plate are accommodated in the battery container, the lead wire attached to the positive electrode plate is connected to the positive electrode terminal provided in the outer container, while being attached to the negative electrode plate. A non-aqueous electrolyte secondary battery is manufactured by connecting the lead wire to a negative electrode terminal provided in the exterior container, and further filling the battery container with a non-aqueous electrification solution and then sealing the battery container.

[Battery pack]
The nonaqueous electrolyte secondary battery using the electrode plate of the present invention as a positive electrode plate and / or a negative electrode plate can be used as a so-called nonaqueous electrolyte secondary battery used in a battery pack. That is, the battery pack of the present invention uses the electrode plate of the present invention as a positive electrode plate and / or a negative electrode plate, and includes a nonaqueous electrolyte secondary battery including a positive electrode terminal and a negative electrode terminal, and a protection circuit having an overdischarge protection function Are housed in a storage case. The battery pack of the present invention is equipped with a protection function for protecting the battery from, for example, overcharge, overdischarge, overcurrent, a short circuit of the battery peripheral circuit, a short circuit between the positive and negative electrodes, etc., in the nonaqueous electrolyte secondary battery itself. In addition, it may be a battery pack in which a protection circuit for preventing overcharge and overdischarge is housed and integrated in a storage case together with the non-aqueous electrolyte secondary battery. The battery pack of the present invention can be suitably used as a battery power supply device for a device that consumes a large amount of power relative to the scale of the device, such as a portable device such as a notebook computer, a camera, or a mobile phone.

  FIG. 9 shows a schematic exploded view of a battery pack 30 of the present invention using a lithium ion secondary battery 31 configured using the electrode plate of the present invention as an embodiment of the battery pack of the present invention. The battery pack 30 includes a lithium ion secondary battery 31 housed in a resin container 36a, a resin container 36b, and an end case 37. At this time, a protection circuit for preventing overcharge and overdischarge between one end face of the lithium ion secondary battery 31 and a face including the positive electrode terminal 32 and the negative electrode terminal 33 and the end case 37. A substrate 34 is provided. The protection circuit board 34 includes an external connection connector 35. The external connection connector 35 is inserted into an external connection window 38a provided in the resin container 36a and an external connection window 38b provided in the end case 37. Connected to an external terminal. The protection circuit board 34 includes a charge / discharge safety circuit (not shown) for controlling charge / discharge, a wiring circuit for connecting the external connection terminal and the lithium ion secondary battery 31, and the like. In addition, the battery pack 30 can employ | adopt the structure of a conventionally well-known battery pack suitably except using the lithium ion secondary battery 31 in which the electrode plate of this invention was used. Although not shown, the battery pack 30 includes a positive electrode lead plate connected to the positive electrode terminal 32, a negative electrode lead plate connected to the negative electrode terminal 33, an insulator, and the like between the lithium ion secondary battery 31 and the end case 37. , May be provided as appropriate.

  In addition, the non-aqueous electrolyte secondary battery of the present invention using the electrode plate of the present invention has functions such as overcurrent blocking and battery temperature monitoring in addition to the above-described protection circuit, in addition to the usage mode for battery packs. And the protection circuit may be used by being integrated with the secondary battery itself. In such an embodiment, the battery pack can be used as a secondary battery having a protection function and a protection circuit without constituting a battery pack, and is highly versatile. In addition, some aspects mentioned above are only illustrations, and do not limit use of the electrode plate of this invention, or the nonaqueous electrolyte secondary battery of this invention at all.

Example 1
<Preparation of electrode plate for non-aqueous electrolyte secondary battery>
The electrode active material layer form liquid for forming the electrode active material layer in the electrode plate for nonaqueous electrolyte secondary batteries was prepared as follows.
First, a solution in which 2.1 g of lithium acetate (Kanto Chemical) and 9.8 g of manganese acetate (Kanto Chemical) was dissolved in 20 g of methanol was prepared. In the above solution, 1 g of a positive electrode active material lithium manganate having an average particle diameter of 4 μm, 1 g of acetylene black HS-100 as a conductive material, 0.2 g of VGCF (Showa Denko), and 0.1 g of a resin hydroxyethyl cellulose are purified water. 5 g of a thickener aqueous solution dissolved in 4.9 g and 0.5 g of a silane coupling agent having an amino group as a functional group (KBM-603, manufactured by Shin-Etsu Silicone Co., Ltd.) are mixed, and Excel Auto Homogenizer (Nippon Seiki Co., Ltd.) is mixed. The electrode active material layer forming liquid was prepared by stirring for 20 minutes at a rotation speed of 7000 rpm in a manufacturing company).

Next, an aluminum foil having a thickness of 15 μm as a current collector is prepared, and the electrode active material layer forming liquid prepared above is applied to one surface side of the current collector, and the weight of the electrode active material layer after drying. Was applied with an applicator so as to be 20 g / m ^2, and dried to form a coating film for forming an electrode active material layer. Subsequently, it pressed using the roll press machine and adjusted the thickness of the coating film. The thickness of the coating film was about 20 μm before pressing and about 12 μm after pressing. Next, the current collector with the electrode active material layer-forming coating film formed on the surface thereof was placed in an electric furnace (high-temperature atmosphere box furnace, manufactured by Koyo Thermo System Co., Ltd., KB8610N-VP) in an air atmosphere. Heating to 450 ° C. over time, and then heating for 10 minutes while maintaining the temperature at 450 ° C. The non-aqueous solution of the present invention in which an electrode active material layer suitable as a positive electrode active material layer is laminated on a current collector An electrode plate for an electrolyte secondary battery was obtained. Then, the electrode plate was allowed to stand until it reached room temperature, then opened to the atmosphere, taken out, and cut into a predetermined size (a disk having a diameter of 15 mm) to obtain Example 1. In addition, the thickness of the coating film for forming an electrode active material layer was calculated by measuring 10 points in any part of the coating film and obtaining an average value. In addition, the content of active material particles per unit area in Example 1 (3.0 mg / 1.77 cm ² ) was calculated from the amount of active material particles used and the like and shown in Table 3.

Film formation evaluation:
In preparing Example 1, the positive electrode plate obtained above was processed into a disk shape of a desired size, but in the processing operation, there was no problem such as peeling of the electrode active material layer. We were able to. From this, it was confirmed that the film forming property of the electrode active material layer was good.
Also in the following examples and comparative examples, as described above, when the electrode plate can be pulled out into a disk shape without any defects, it is evaluated that the film forming property of the electrode active material layer is good. . On the other hand, part of the electrode active material layer is peeled off in the above-mentioned punching process, or the active material particles fall from the current collector, etc., and the processing is poor, and it is used as a working electrode of a tripolar coin cell to be described later In the case where a disk that can withstand the above is not formed, it is evaluated that the film forming property of the electrode active material layer is poor.

Cyclic voltammetry test (CV test):
Moreover, in order to confirm beforehand whether the metal oxide which is a binder contained in the electrode active material layer in Example 1 exhibits a lithium ion insertion / release reaction, the following test was performed. . That is, except that lithium manganate particles as positive electrode active material particles were not used, a solution was prepared in the same manner as in the electrode active material layered liquid used in Example 1, and this was used in the same manner as in Example 1. A laminate was prepared and used as Reference Example 1. And the CV test was done using the above Reference Example 1. Specifically, the operation of first sweeping the electrode potential from 3.0 V to 4.3 V and then returning it to 3.0 V was repeated three times. The scanning speed was 1 mV / sec. In the cyclic voltammogram showing the results of the second cycle, an oxidation peak corresponding to the Li elimination reaction of LiMn ₂ O ₄ was observed near 3.9 V, and a reduction peak corresponding to the Li insertion reaction was confirmed near 4.1 V. . Thus, it was confirmed that the metal oxide contained in the electrode active material layer exhibits a lithium-on insertion / release reaction. The CV test was performed using VMP3 manufactured by Bio Logic.

<Production of tripolar coin cell>
Lithium hexafluorophosphate (LiPF ₆ ) is added as a solute to a mixed solvent of ethylene carbonate (EC) / dimethyl carbonate (DMC) (volume ratio = 1: 1), and the concentration of LiPF _{6 as} the solute is 1 mol. The non-aqueous electrolyte was prepared by adjusting the concentration to be / L. Example 1 produced as described above as a positive electrode plate was used as a working electrode plate, a metal lithium plate was used as a counter electrode plate and a reference electrode plate, and the non-aqueous electrolyte produced as described above was used as an electrolytic solution. And this was designated as Example Test Cell 1. The example test cell 1 was subjected to the following charge / discharge test.

<Charge / discharge test>
In the example test cell 1, which is a tripolar coin cell created as described above, the example test cell 1 was first fully charged as shown in the following charging test in order to conduct a discharge test of the working electrode plate.
(Charge test)
Example Test cell 1 was charged at a constant current (270 μA) under a 25 ° C. environment until the voltage reached 4.3 V, and after the voltage reached 4.3 V (full charge voltage), The current (discharge rate: 1 C) was reduced until the voltage became 5% or less so that the voltage did not exceed 4.3 V, the battery was charged at a constant voltage, fully charged, and then rested for 10 minutes. Here, the “1C” means a current value (current value reaching the discharge end voltage) at which constant current discharge is performed using the tripolar coin cell and discharge is completed in one hour. In addition, the constant current is a capacity that can be discharged in 1 hour (90 mAh / g in the case of lithium manganate in Example 1) in the working electrode plate in Example Test Cell 1 in 1 hour in this charge / discharge test. The current value is set to complete the discharge.

(Discharge test)
Thereafter, the fully charged example test cell 1 was subjected to a constant current (270 μA) (discharge) in an environment of 25 ° C. until the voltage changed from 4.3 V (full charge voltage) to 3.0 V (discharge end voltage). A constant current discharge at a rate of 1 C), the cell voltage (V) on the vertical axis, the discharge time (h) on the horizontal axis, a discharge curve is created, and the discharge capacity (mAh) of the electrode plate for positive electrode is obtained. The electrode capacity (μAh) of the electrode plate (15 mmφ test cell) was determined.

DC resistance measurement:
Using the example test cell 1, the DC resistance value of the electrode plate was calculated as follows. When a discharge test is performed under the condition of a discharge rate of 1C, a voltage value (V1) (mV) 10 seconds after the start of discharge is measured. Furthermore, also when the discharge test is performed under the condition of the discharge rate 5C, the voltage value (V5) (mV) 10 seconds after the start of discharge is measured. Based on these measured values (V1, V5) and the constant current values (I1, I5) (mA) corresponding to the discharge rates 1C and 5C, the DC resistance value (Ω) is expressed by the following equation (2). Calculated. The results are shown in Table 3.

Initial charge / discharge efficiency:
The initial charge / discharge efficiency of Example 1 was determined as follows. That is, in the first charge test at the constant current of 270 μA (equivalent to 1C), the vertical axis represents the applied current (mA), the horizontal axis represents the charging time (h), the charging curve was created, and the area (current × time) The charge capacity (μAh) of the positive electrode plate is obtained from the area obtained by the above calculation, and the discharge capacity (μAh) of the positive electrode plate is the same in the first discharge test at the constant current of 270 μA (equivalent to 1C). Was measured, and the initial charge / discharge efficiency was calculated from the formula: (Measured discharge capacity of electrode plate (μAh)) / (Measured charge capacity of electrode plate (μAh)) × 100.

(Examples 2-5, Examples 8-10)
An electrode active material layer solution was prepared in the same manner as in Example 1 except that the type or amount of the coupling agent used was changed to the contents shown in Table 1. And the electrode plate was produced similarly to Example 1, and it cut | judged to the predetermined magnitude | size, and was set as Examples 2-5, respectively. The coupling agent KBM-403 is a silane coupling agent (manufactured by Shin-Etsu Silicone Co., Ltd.) having an epoxy group as a functional group, and the silane coupling agent KBE-903 is a silane cup having an amino group as a functional group. It is a ring agent (manufactured by Shin-Etsu Silicone). In addition, as the titanate coupling agent (TC200), Matsumoto Kosho Co., Ltd., aluminum coupling agent (Plenact AL-M) manufactured by Ajinomoto Fine Techno Co., Ltd. was used.

(Example 6)
An electrode plate was prepared in the same manner as in Example 1. And Example 1 was immersed in the immersion tank with which the resin liquid mixture prepared as follows was filled, and the said resin liquid mixture was fully osmose | permeated in the space | gap of Example 1. FIG. Then, Example 1 was taken out from the said immersion layer, and it set in the oven heated at 150 degreeC, it was made to dry for 15 minutes, and the solvent of the resin liquid mixture was removed. Thus, a positive electrode plate in which the resin binder remained in the electrode active material layer was prepared, and this was designated as Example 6. The resin mixed solution was prepared by using PVDF resin as a resin material and mixing it with an NMP solvent so that the concentration of PVDF was 0.1%.

(Example 7)
A positive electrode plate was prepared in the same manner as in Example 6 except that the concentration of the PVDF resin was adjusted to 5%.

(Comparative Example 1)
The electrode active material layer form liquid for forming the electrode active material layer in the electrode plate for nonaqueous electrolyte secondary batteries was prepared as follows. 10 g of positive electrode active material lithium manganate having an average particle size of 4 μm, 1 g of acetylene black HS-100 as a conductive material, 0.2 g of VGCF (manufactured by Showa Denko KK), and PVDF (manufactured by Kureha, KF # 1100) 1 3 g of organic solvent NMP (Mitsubishi Chemical Co., Ltd.) is added and dispersed, and an Excel auto homogenizer (Nihon Seiki Seisakusho Co., Ltd.) is rotated at 7000 rpm so that the solid content concentration becomes 55% by weight. The mixture was stirred for 15 minutes to prepare a slurry-like electrode active material layer forming liquid.

The electrode active material layered solution prepared above is applied onto a 15 μm thick aluminum foil used as a positive electrode current collector so that the coating amount of the electrode active material layer solution after drying is 22 g / m ^2. And dried in an air atmosphere at 120 ° C. using an oven to form an electrode active material layer.
Furthermore, after pressing using a roll press machine so that the coating density of the formed electrode active material layer is 1.5 g / cm ³ (thickness of the electrode active material layer: 15 μm), a predetermined size is obtained. The resultant was cut into (15 mmφ) and vacuum-dried at 140 ° C. for 5 minutes to produce a positive electrode plate.

(Comparative Example 2)
Except that the shape-changing agent was not added to the electrode active material layer forming liquid, and the heating conditions of the current collector with the electrode active material layer forming coating film formed on the surface were changed to the contents shown in Table 1. As in Example 2, an electrode plate was prepared and cut into a predetermined size to obtain Comparative Example 2.

  For Examples 2 to 10, Comparative Example 1 and Comparative Example 2 described above, as in Example 1, measurement of the thickness of the formed electrode active material layer, evaluation of film formation, adhesion of the electrode active material layer Evaluation was performed. The results are shown in Table 2.

  For Examples 2 to 10 described above, Comparative Example 1 and Comparative Example 2 as well as Reference Example 1 related to Example 1, except that the active material particles were removed, each of the Examples and Comparative Examples was performed in the same manner. A reference example was prepared, a CV test was performed in the same manner as described above, and a lithium ion of a metal oxide (comparative example 1 using only a resin binder) is a lithium ion The presence or absence of an insertion / elimination reaction was confirmed. The result is “Yes” when the peak was confirmed and showed a lithium insertion / elimination reaction, and “No” when the peak was not confirmed and showed no lithium insertion / elimination reaction. The results are collectively shown as “insertion and desorption reaction of Li as a binder”.

  In addition, for Examples 2 to 10 and Comparative Example 1 and Comparative Example 2 described above, Example Test Cells 2 to 10 and Comparative Example Test Cell 1 and Comparative Example Test Cell 2 were prepared in the same manner as Example Test Cell 1 described above. The charge / discharge test was conducted in the same manner as described above except that the constant current value, the full charge voltage value, and the discharge end voltage value were changed. Table 3 summarizes the specific constant current value, full charge voltage value, and end-of-discharge voltage value of each test cell. And like Example 1, it calculated | required about the weight of the active material particle | grains per unit area, an electrode capacity | capacitance, DC resistance value, and initial stage charge / discharge efficiency. The results are shown in Table 3.

Scanning electron microscope photography:
The surface of the electrode active material layer in Example 1 was photographed with a scanning electron microscope at a magnification of 10,000 times and 50,000 times, and shown as FIGS. 2 and 3, respectively. In addition, the surface of the electrode active material layer in Example 2 was photographed with a scanning electron microscope at magnifications of 10,000 and 50,000, and are shown as FIGS. 4 and 5, respectively. From FIG. 2 and FIG. 3, the metal oxide, which is a binder contained in the electrode active material layer of Example 1, is a continuous pleated coating layer covering a plurality of active material particles, It is confirmed that a plurality of needle-like protrusions are present on the surface of the coating layer. Also, from FIG. 4 and FIG. 5, the metal oxide that is the binder contained in the electrode active material layer of Example 2 is a continuous covering layer covering a plurality of active material particles, Further, it is confirmed that a plurality of scale-like protrusions are present on the surface of the coating layer.
Similarly, the surface of the electrode active material layer of Comparative Example 1 was photographed with a scanning electron microscope at a magnification of 10,000 times and a magnification of 50,000 times, and shown as FIGS. 10A and 10B, respectively. From FIG. 10B, it is confirmed that the resin binder joins the active material particles and the conductive material.
Similarly, the surface of the electrode active material layer of Comparative Example 2 was photographed with a scanning electron microscope at a magnification of 10,000 times and shown in FIG. From FIG. 11, it is confirmed that the metal oxide as the binding material has a particulate shape.

(Example consideration)
As shown in Table 3, in Examples 1 to 5, all of the electrode active material layers were formed without using the resin binder, but all of the film forming properties were good and the resin binder was used. It was confirmed that the adhesion to the current collector was as good as that of the comparative example. Therefore, it was confirmed that the metal oxide formed in the electrode active material layer acts as a binder. In addition, in Examples 1 to 7, it was confirmed that all of the reference examples prepared by removing the active material particles showed a lithium ion insertion / release reaction, and the metal was a binding material present in the electrode active material layer. It was confirmed that the oxide exhibits a lithium ion insertion / release reaction.

  Moreover, as shown in Table 3, although the weight of the active material particles per unit area in the electrode active material layer is less than that of Comparative Example 1 in Examples 1 to 7, 9 and 10, the electrode capacity ( μAh) was almost the same in Examples and Comparative Examples. Similarly, in Example 8, although the weight of the active material particles per unit area in the electrode active material layer is smaller than that in Comparative Example 3, the electrode capacity (μAh) of the electrode plate is the same as in Example 8 and Comparative Example 3. It was almost the same. From this result, in the electrode plate of the present invention, the metal oxide produced in the electrode active material layer acts as a binding material and also acts as an active material by causing a lithium ion insertion / release reaction. It has been confirmed that the effect of substantially increasing the electrode capacity is exhibited. Further, each of Examples 1 to 10 was shown to have a lower DC resistance value than Comparative Examples 1 to 3, a good conductive path, and excellent input / output characteristics.

  In addition, Examples 1 to 10 had lower DC resistance values and higher initial charge / discharge efficiencies than Comparative Examples 1 to 3. In addition, Example 2 showed better results in any of electrode capacity, DC resistance value, and initial charge / discharge efficiency than Comparative Example 2. As a result, the binding material constitutes a coating layer that coats the active material particles, and there are a plurality of protrusions on the surface of the coating layer, and the surface opposite to the active material particles is contracted and raised. It was confirmed that excellent performance was exhibited by showing a continuous pleated or humped layer structure.

  In addition, Examples 6 and 7 each including an electrode active material layer including a metal oxide as a binder and a resin binder have the same DC resistance, electrode capacity, and initial charge / discharge efficiency as those in Example 2. It was confirmed that

  In addition, Examples 1 to 10 are those in which the direct current resistance value of the electrode plate itself was evaluated, but in any of the electrode plates, the direct current resistance is low, the electrode capacity is large, and the initial charge and discharge efficiency is high. When a lithium ion secondary battery is made using either or both of these electrode plates, it is naturally suggested that the battery input / output performance, battery capacity, initial charge / discharge efficiency, etc. are improved. It was. In addition, it is suggested that the non-aqueous electrolyte secondary battery and the battery pack using any one of the electrode plates of Examples 1 to 10 as the positive electrode plate and / or the negative electrode plate also improve the input / output characteristics and the battery capacity. It was.

1, 1 ′, 1 ″, 55 Current collector 2, 2 ′, 54 Electrode active material layer 3 Current collecting base material 4 Conductive layer 5 Intermittent layer 6 Void 7 Corrugated coating layer 8 Protrusions 10, 20, 20 ', 20'',20''' electrode plate 21 for non-aqueous electrolyte secondary battery 21 active material particles 30 battery pack 31 lithium ion secondary battery 32 positive electrode terminal 33 negative electrode terminal 34 protective circuit board 35 external connection connectors 36a, 36b Resin container 37 End case 38a, 38b External connection window 50 Nonaqueous electrolyte secondary battery electrode plate (positive electrode plate)
70 Separator 81, 82 Exterior 90 Non-aqueous electrolyte 100 Lithium ion secondary battery 101, 102, 103, 103 ′ Current collector surface

Claims (13)

An electrode plate for a nonaqueous electrolyte secondary battery comprising a current collector and an electrode active material layer formed on at least a part of the surface of the current collector,
The electrode active material layer contains active material particles and a binder,
The binder is a metal oxide that exhibits a lithium ion insertion / release reaction,
The metal oxide constitutes a coating layer covering a plurality of active material particles,
An electrode plate for a non-aqueous electrolyte secondary battery, wherein the surface of the coating layer has a plurality of protrusions. 2. The non-aqueous electrolyte secondary battery according to claim 1, wherein at least a surface of the coating layer opposite to a surface on the side of the active material particle to be coated is contracted and raised. Electrode plate. The electrode plate for a nonaqueous electrolyte secondary battery according to claim 1, wherein the metal oxide is a lithium composite oxide. 4. The metal oxide according to claim 1, wherein the metal oxide is a composite oxide of at least one metal selected from cobalt, nickel, manganese, iron, and titanium and lithium. 5. The electrode plate for non-aqueous electrolyte secondary batteries according to any one of the above. The electrode plate for a nonaqueous electrolyte secondary battery according to any one of claims 1 to 4, wherein the active material particles and the metal oxide are the same compound. The electrode active material layer is configured such that active material particles are fixed to each other by a binding material, and the active material particles are fixed to a current collector by a binding material. The electrode plate for a nonaqueous electrolyte secondary battery according to any one of 1 to 5. The electrode plate for a non-aqueous electrolyte secondary battery according to any one of claims 1 to 6, wherein the binder material covers at least a part of the surface of the active material particles. A non-aqueous electrolyte secondary battery comprising at least a positive electrode plate, a negative electrode plate, a separator provided between the positive electrode plate and the negative electrode plate, and an electrolyte containing a non-aqueous solvent,
Either one or both of the positive electrode plate and the negative electrode plate is the electrode plate for a non-aqueous electrolyte secondary battery according to any one of claims 1 to 7, wherein the non-aqueous electrolyte solution 2 Next battery. Application step of applying an electrode active material layer forming liquid containing at least active material particles and one or more metal element-containing compounds to at least a part of the current collector to form a coating film When,
The electrode which forms the electrode active material layer which contains this metal oxide and the said active material particle on the said collector by making the metal element containing compound contained in the said coating film react, and producing | generating a metal oxide An active material layer forming step in this order,
The metal element-containing compound used in the coating step is selected in advance so that the metal oxide generated in the electrode active material layer forming step becomes a metal oxide exhibiting a lithium ion insertion / release reaction, and
The electrode active material layer-forming liquid contains a shape change agent for coating the metal oxide with a plurality of active material particles, the surface layer having a plurality of protrusions. A method for producing an electrode plate for a non-aqueous electrolyte secondary battery. The method for producing an electrode plate for a non-aqueous electrolyte secondary battery according to claim 9, wherein the shape change agent is a coupling agent. The method for producing an electrode plate for a nonaqueous electrolyte secondary battery according to claim 9 or 10, wherein at least a lithium salt is used as the metal element-containing compound. 12. The metal element-containing compound, wherein at least one metal salt containing a metal selected from cobalt, nickel, manganese, iron and titanium and a lithium salt are used. The manufacturing method of the electrode plate for nonaqueous electrolyte secondary batteries of any one of these. A storage case; a non-aqueous electrolyte secondary battery including a positive electrode terminal and a negative electrode terminal; and a protection circuit having an overcharge and over-discharge protection function, wherein the storage case includes the non-aqueous electrolyte secondary battery and the In a battery pack configured to contain a protection circuit,
The non-aqueous electrolyte secondary battery includes at least a positive electrode plate, a negative electrode plate, a separator provided between the positive electrode plate and the negative electrode plate, and an electrolyte solution containing a non-aqueous solvent. A secondary battery,
Either one of the said positive electrode plate or a negative electrode plate, or both are the electrode plates for nonaqueous electrolyte secondary batteries of any one of Claim 1 to 7, The battery pack characterized by the above-mentioned.