JP7275300B2 - All-solid lithium secondary battery and method for manufacturing all-solid lithium secondary battery - Google Patents

Description

TECHNICAL FIELD The present invention relates to an all-solid lithium secondary battery and a method for manufacturing an all-solid lithium secondary battery.

Lithium-ion batteries using non-aqueous electrolytes are commonly used. However, the lithium-ion battery has a flammable electrolyte, which may cause a fire or the like, and an organic solvent is used. Therefore, an all-solid lithium secondary battery using a polymer electrolyte has been developed. However, the polymer electrolyte has low ionic conductivity at low temperatures, and the usable temperature range is narrower than that of the lithium ion battery using the non-aqueous electrolyte. Therefore, an all-solid lithium secondary battery using a sulfide-based solid electrolyte has been developed. However, sulfides can react with water to generate hydrogen sulfide, which limits the temperature range in which they can be used. Therefore, development of an all-solid-state battery using an oxide-based solid electrolyte that can compensate for such drawbacks of polymer electrolytes and sulfide-based electrolytes is expected.

For example, in Patent Document 1 below, a composite solid electrolyte layer having lithium ion conductive oxide particles and a lithium ion conductive amorphous portion interposed between the oxide particles is combined with a positive electrode having a positive electrode active material. An all-solid-state lithium secondary battery sandwiched between a negative electrode having a negative electrode active material is described.

Further, Patent Document 2 below describes a solid electrolyte for an all-solid lithium ion secondary battery using an oxide solid electrolyte. In this solid electrolyte, an adhesive layer having lithium ion conductivity is provided on the surface of the solid electrolyte body for the purpose of reducing the resistance at the interface between the solid electrolyte body and the electrode.

JP 2015-138741 A JP 2017-069036 A

The all-solid lithium secondary battery using the oxide solid electrolyte as described in Patent Document 1 is easy to handle because it does not easily react with water to generate hydrogen sulfide, but the sulfide electrolyte is used. High internal resistance and low conductivity compared to all-solid lithium secondary batteries.

Further, the adhesive layer of the solid electrolyte described in Patent Document 2 is preferably as thin as possible because the ionic conductivity is one order of magnitude lower than that of the solid electrolyte body. However, if the adhesive layer is made thin, there is a possibility that the gap between the electrode and the solid electrolyte body cannot be filled, and there is a concern that the internal resistance will rather increase.

Therefore, in all-solid lithium secondary batteries using an oxide solid electrolyte that is easy to handle, it is desired to reduce the internal resistance and achieve a large current.

Accordingly, an object of the present invention is to provide an all-solid lithium secondary battery that is easy to handle and can achieve a large current, and a method for manufacturing the all-solid lithium secondary battery.

In order to solve the above problems, the all-solid lithium secondary battery of the present invention comprises an oxide solid electrolyte layer containing oxide solid electrolyte particles having lithium ion conductivity, and on one surface side of the oxide solid electrolyte layer a positive electrode active material layer disposed; a negative electrode active material layer disposed on the other side of the oxide solid electrolyte layer; at least one of the positive electrode active material layer and the negative electrode active material layer; and the oxide solid electrolyte a solid electrolyte dispersed polymer layer in which the oxide solid electrolyte particles are dispersed in a lithium ion conductive polymer material having lithium ion conductivity, the positive electrode active material layer and and the negative electrode active material layer, the solid electrolyte-dispersed polymer layer, and the oxide solid electrolyte layer are integrated.

Unlike the above sulfides, oxides do not easily generate gases such as hydrogen sulfide that require careful handling even when reacted with water. Therefore, the all-solid lithium secondary battery of the present invention using an oxide solid electrolyte is easy to handle.

In addition, the state in which layers are integrated in this specification means a state in which they cannot be separated and breakage occurs when they are forcibly separated. Therefore, in the all-solid lithium secondary battery of the present invention, the positive electrode active material layer, the negative electrode active material layer, the solid electrolyte dispersed polymer layer, and the oxide solid electrolyte layer are in a state in which they cannot be separated. The resistors among the positive electrode active material layer, the negative electrode active material layer, the solid electrolyte-dispersed polymer layer, and the oxide solid electrolyte layer, which are integrated in this way, are not integrated and are simply arranged adjacent to each other. It is lower than the resistance between the positive electrode active material layer, the negative electrode active material layer, the solid electrolyte dispersed polymer layer, and the oxide solid electrolyte layer.

Further, in the all-solid lithium secondary battery of the present invention, the solid electrolyte dispersed polymer layer comprises a lithium ion conductive polymer material having lithium ion conductivity and oxide solid electrolyte particles dispersed in this material. include. In general, oxide solid electrolyte particles have higher lithium ion conductivity than lithium ion conductive polymer materials. higher than a layer consisting only of a flexible polymeric material. Therefore, the solid electrolyte-dispersed polymer layer of the present invention can be formed thicker than the layer composed only of the lithium ion conductive polymer material such as the adhesive layer of Patent Document 2 above. Therefore, it is possible to suppress an increase in internal resistance caused by the inability to fill the gap between the electrode and the solid electrolyte body, unlike the adhesive layer of Patent Document 2 described above. Therefore, according to the all-solid-state lithium secondary battery of the present invention, the internal resistance is reduced and a large current can be achieved.

Further, in the method for producing an all-solid lithium secondary battery of the present invention, a positive electrode active material layer is positioned on one side of an oxide solid electrolyte layer containing oxide solid electrolyte particles and having lithium ion conductivity, and an oxide A negative electrode active material layer is positioned on the other side of the solid electrolyte layer, and lithium having lithium ion conductivity is present between at least one of the positive electrode active material layer and the negative electrode active material layer and the oxide solid electrolyte layer. The oxide solid electrolyte layer, the positive electrode active material layer, the negative electrode active material layer, and the an arrangement step of arranging the solid electrolyte-dispersed polymer layer; and integration of integrating the positive electrode active material layer, the negative electrode active material layer, the solid electrolyte-dispersed polymer layer, and the oxide solid electrolyte layer. and a step.

According to such a method for manufacturing an all-solid lithium secondary battery, it is possible to manufacture an all-solid lithium secondary battery that uses an oxide solid electrolyte that is easy to handle, has a reduced internal resistance, and can achieve a large current. can be done.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, an all-solid lithium secondary battery that is easy to handle and can achieve a large current, and a method for manufacturing an all-solid lithium secondary battery are provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows sectional drawing of the all-solid-state lithium secondary battery which concerns on embodiment of this invention. FIG. 2 is an enlarged view from a positive electrode active material layer to an oxide solid electrolyte layer in FIG. 1; 2 is an enlarged view from the negative electrode active material layer to the oxide solid electrolyte layer in FIG. 1. FIG. 1 is a flow chart of a method for manufacturing an all-solid lithium secondary battery according to an embodiment of the present invention; It is a figure which shows the mode of a preparation process. It is a figure which shows the mode of an arrangement|positioning process. It is a figure which shows the mode of an integration process. 4 is a Cole-Cole plot showing the measurement results of Examples.

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of an all-solid lithium secondary battery and a method for manufacturing an all-solid lithium secondary battery according to the present invention will now be described in detail with reference to the drawings. In addition, the embodiment illustrated below is for facilitating understanding of the present invention, and is not for limiting and interpreting the present invention. The present invention can be modified and improved without departing from its spirit. Also, for ease of understanding, there are cases where a part of each drawing is exaggerated.

FIG. 1 is a diagram showing a cross-sectional view of an all-solid lithium secondary battery according to an embodiment of the present invention. As shown in FIG. 1, the all-solid lithium secondary battery 1 of this embodiment has a battery body 1b arranged in a packaging material 10. As shown in FIG. The battery body 1b includes an oxide solid electrolyte layer 11, a positive electrode side solid electrolyte dispersed polymer layer 12, a positive electrode active material layer 13, a positive electrode current collector layer 14, and a negative electrode side solid electrolyte dispersed polymer layer 15. , a negative electrode active material layer 16 and a negative electrode current collector layer 17 as main components.

<Oxide solid electrolyte layer>
FIG. 2 is an enlarged view from the positive electrode active material layer 13 to the oxide solid electrolyte layer 11 in FIG. As shown in FIG. 2, in the oxide solid electrolyte layer 11, the lithium ion conductive polymer material 11b enters at least partly between the oxide solid electrolyte particles 11a. It is configured such that the lithium ion conductive polymer material 11b is arranged at least partly between the particles.

The oxide solid electrolyte constituting the oxide solid electrolyte particles 11a is not particularly limited as long as it is an oxide solid electrolyte having lithium ion conductivity. Examples include lithium aluminum titanium phosphate (LATP) and lithium lanthanum zirconium oxide. (LLZO), lithium lanthanum titanium oxide (LLTO), aluminum-substituted lithium germanium phosphate (LAGP), and the like. Silicon (Si) or germanium (Ge) may be added to LATP.

The average particle diameter of the oxide solid electrolyte particles 11a is, for example, 0.1 μm or more and 5 μm or less. In this specification, the particle size refers to an average particle size measured by, for example, a 1090L laser diffraction particle size distribution analyzer manufactured by CILAS.

The lithium ion conductive polymer material 11b that enters between the particles of the oxide solid electrolyte particles 11a has lithium ion conductivity. As such a lithium ion conductive polymer material 11b, a polymer material having lithium ion conductivity can be mentioned. Examples of such polymer materials include polyethylene oxide (PEO), polyethylene glycol (PEG), and polyvinylidene fluoride (PVDF). Further, as the lithium ion conductive polymer material 11b, a polymer containing a lithium salt can be mentioned. In other words, the polymer does not have lithium ion conductivity, but has lithium ion conductivity when the lithium salt, which is a supporting salt, is contained in the polymer. Examples of such lithium salts include lithium hexafluorophosphate (LiPF ₆ ), lithium borofluoride (LiBF ₄ ), lithium bis(oxalate)borate (LiBOB), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI ), lithium bis(fluorosulfonyl)imide (LiFSI). In addition, a configuration in which a polymer having lithium ion conductivity such as PEO, PEG, or PVDF contains a lithium salt may be used. Furthermore, it is preferable to mix lithium ion conductive oxide solid electrolyte particles with the polymer having lithium ion conductivity. As the oxide solid electrolyte particles in this case, particles similar to the oxide solid electrolyte that can be used for the oxide solid electrolyte particles 11a can be mentioned. In particular, lithium ion conductive oxides such as LATP and LLZO tend to have high lithium ion conductive polymer ion conductivity, so mixing them can further increase the lithium ion conductivity.

As described above, the oxide solid electrolyte layer 11 of the present embodiment has a structure in which the lithium ion conductive polymer material 11b enters between the oxide solid electrolyte particles 11a. The resistance can be reduced compared to the case where the lithium ion conductive polymer material 11b does not enter between the oxide solid electrolyte particles 11a, which are composed only of the electrolyte particles 11a. The oxide solid electrolyte layer 11 having such a configuration is sometimes called a composite solid electrolyte layer.

<Positive electrode active material layer>
The positive electrode active material layer 13 of the present embodiment has a structure in which the lithium ion conductive polymer material 13b is inserted between the positive electrode active materials 13a, and has lithium ion conductivity.

The material constituting the positive electrode active material 13a is not particularly limited as long as it contains lithium and can take in and release lithium ions. Examples include lithium manganate (LMO), lithium cobalt oxide (LCO), Lithium nickel oxide (LNO), ternary system (NMC or NCA), lithium iron phosphate (LFP), vanadium phosphate oxide (LVP), cobalt manganese phosphate (LCMP), and mixtures thereof can be mentioned. The term "ternary system" as used herein means containing, for example, nickel, manganese or aluminum, and cobalt.

As the lithium ion conductive polymer material 13b that enters between the positive electrode active materials 13a, materials similar to those that can be used for the lithium ion conductive polymer material 11b can be used. In this embodiment, the lithium ion conductive polymer material 13b that enters between the positive electrode active materials 13a and the lithium ion conductive polymer material 11b that enters between the oxide solid electrolyte particles 11a are made of the same material. or different materials.

Further, a conductive aid such as acetylene black may be dispersed in the lithium ion conductive polymer material 13b of the positive electrode active material layer 13 .

<Positive electrode side solid electrolyte dispersed polymer layer>
In this embodiment, a solid electrolyte dispersed polymer layer in which oxide solid electrolyte particles 12a are dispersed in a lithium ion conductive polymer material 12b between the positive electrode active material layer 13 and the oxide solid electrolyte layer 11 A positive electrode-side solid electrolyte-dispersed polymer layer 12 is interposed. As the lithium ion conductive polymer material 12b constituting the positive electrode-side solid electrolyte dispersed polymer layer 12, materials similar to those that can be used for the lithium ion conductive polymer material 11b of the oxide solid electrolyte layer 11 are listed. be able to.

As the oxide solid electrolyte forming the oxide solid electrolyte particles 12a of the positive electrode-side solid electrolyte-dispersed polymer layer 12, an oxide solid electrolyte that can be used for the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 can include oxide solid electrolytes similar to . From the viewpoint of reducing contact resistance, the oxide solid electrolyte particles 12a of the positive electrode-side solid electrolyte-dispersed polymer layer 12 and the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 are made of the same oxide solid electrolyte. preferable. Further, the oxide solid electrolyte particles 12a of the positive electrode-side solid electrolyte-dispersed polymer layer 12 and the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 may be made of different oxide solid electrolytes. In this case, for example, LAGP or LLZO is used as the oxide solid electrolyte constituting the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11, and the oxide solid electrolyte particles of the positive electrode-side solid electrolyte-dispersed polymer layer 12 are used. LATP is used for the oxide solid electrolyte that constitutes 12a. With such a combination, the reduction resistance of the oxide solid electrolyte can be improved.

Moreover, the particle size of the oxide solid electrolyte particles 12 a of the positive electrode-side solid electrolyte dispersed polymer layer 12 may be the same as the particle size of the oxide solid electrolyte particles 11 a of the oxide solid electrolyte layer 11 . In this case, the average particle size of the oxide solid electrolyte particles 12a is, for example, 0.1 μm or more and 5 μm or less. However, the particle size of oxide solid electrolyte particles 12 a in positive electrode-side solid electrolyte-dispersed polymer layer 12 may differ from the particle size of oxide solid electrolyte particles 11 a in oxide solid electrolyte layer 11 . For example, if the particle size of the oxide solid electrolyte particles 12a of the positive electrode-side solid electrolyte dispersed polymer layer 12 is smaller than the particle size of the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11, the positive electrode-side solid electrolyte dispersion height This is preferable because the molecular layer 12 can be made thinner and the resistance of the all-solid lithium secondary battery 1 can be reduced. Further, when forming the positive electrode-side solid electrolyte-dispersed polymer layer 12 by coating as described later, the oxide solid electrolyte particles 12a are placed between the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 to provide lithium ion conductivity. It can be embedded with polymeric material 12b. However, the particle size of oxide solid electrolyte particles 12 a in positive electrode-side solid electrolyte-dispersed polymer layer 12 may be larger than the particle size of oxide solid electrolyte particles 11 a in oxide solid electrolyte layer 11 .

The average thickness of positive electrode-side solid electrolyte-dispersed polymer layer 12 may be smaller than the particle size of oxide solid electrolyte particles 12a. In this case, the positive electrode-side solid electrolyte-dispersed polymer layer 12 is thicker at portions where the oxide solid electrolyte particles 12a are located, and is thinner at portions where the oxide solid electrolyte particles 12a are not located. Therefore, the oxide solid electrolyte particles 12a easily come into contact with the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 and the positive electrode active material 13a.

Moreover, in the positive electrode side solid electrolyte dispersed polymer layer 12, the volume ratio of the oxide solid electrolyte particles 12a is preferably larger than the volume ratio of the lithium ion conductive polymer material 12b. By doing so, the resistance of the positive electrode side solid electrolyte dispersed polymer layer 12 can be further reduced.

In this embodiment, the oxide solid electrolyte layer 11 and the positive electrode-side solid electrolyte-dispersed polymer layer 12 are integrated, and the positive electrode active material layer 13 and the positive electrode-side solid electrolyte-dispersed polymer layer 12 are integrated. The oxide solid electrolyte layer 11 and the positive electrode active material layer 13 are integrated with the positive electrode side solid electrolyte dispersed polymer layer 12 interposed therebetween. Therefore, when the oxide solid electrolyte layer 11 and the positive electrode active material layer 13 are peeled off, the cell structure is destroyed.

It should be noted that the lithium ion conductive polymer material 15b constituting the positive electrode side solid electrolyte dispersed polymer layer 12 and the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a are made of the same material. , is preferable from the viewpoint that the integration strength between the positive electrode-side solid electrolyte-dispersed polymer layer 12 and the oxide solid electrolyte layer 11 can be increased. In this case, it is also preferable from the viewpoint that the positive electrode-side solid electrolyte-dispersed polymer layer 12 and the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a can be simultaneously formed by coating. However, even if the lithium ion conductive polymer material 12b of the positive electrode side solid electrolyte dispersed polymer layer 12 and the lithium ion conductive polymer material 11b interposed between the oxide solid electrolyte particles 11a are the same material. A positive electrode-side solid electrolyte-dispersed polymer layer 12 may be provided on the positive electrode side surface of the oxide solid electrolyte layer 11 in which the lithium ion conductive polymer material 11b is inserted between the oxide solid electrolyte particles 11a. Further, the lithium ion conductive polymer material forming the positive electrode side solid electrolyte dispersed polymer layer 12 and the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a may be different materials. . In this case, for example, PVDF is used as the lithium ion conductive polymer material constituting the positive electrode side solid electrolyte dispersed polymer layer 12, and as the lithium ion conductive polymer material 11b that enters between the oxide solid electrolyte particles 11a, Preferably PEO is used. With such a combination, the cell voltage can be increased by using PVDF, which is less likely to be decomposed than PEO on the high potential side. Therefore, it can contribute to increase the potential and energy of the all-solid lithium secondary battery 1 .

Further, the lithium ion conductive polymer material forming the positive electrode side solid electrolyte dispersed polymer layer 12 and the lithium ion conductive polymer material 13b inserted between the positive electrode active materials 13a are made of the same material. This is preferable from the viewpoint that the integration strength between the solid electrolyte-dispersed polymer layer 12 and the positive electrode active material layer 13 can be increased. Further, the lithium ion conductive polymer material forming the positive electrode side solid electrolyte dispersed polymer layer 12 and the lithium ion conductive polymer material 13b inserted between the positive electrode active materials 13a may be different materials. In this case, for example, PEO is used as the lithium ion conductive polymer material 12b constituting the positive electrode side solid electrolyte dispersed polymer layer 12, and PVDF is used as the lithium ion conductive polymer material 13b that enters between the positive electrode active materials 13a. is preferably used. With such a combination, the cell voltage can be increased by using PVDF, which is less likely to be decomposed than PEO on the high potential side. Therefore, it can contribute to increase the potential and energy of the all-solid lithium secondary battery 1 .

<Positive collector layer>
The positive electrode current collector layer 14 is arranged on the side of the positive electrode active material layer 13 opposite to the oxide solid electrolyte layer 11 side, and is integrated with the positive electrode active material layer 13 . The positive electrode current collector layer 14 is made of an electrically conductive and non-ionically conductive material. Examples of such materials include metals and carbon sheets, and examples of such metals include copper, aluminum, iron-nickel alloys, and the like.

<Negative electrode active material layer>
FIG. 3 is an enlarged view from the negative electrode active material layer 16 to the oxide solid electrolyte layer 11 in FIG. The negative electrode active material layer 16 of the present embodiment has lithium ion conductivity because the lithium ion conductive polymer material 16b is inserted between the negative electrode active materials 16a.

The material constituting the negative electrode active material 16a is not particularly limited as long as it can take in and release lithium ions. A mixture of these and the like can be mentioned.

Examples of the lithium ion conductive polymer material 16b that enters between the negative electrode active materials 16a include materials that can be used for the lithium ion conductive polymer material 11b. In the present embodiment, the lithium ion conductive polymer material 16b that enters between the negative electrode active materials 16a and the lithium ion conductive polymer material 11b that enters between the oxide solid electrolyte particles 11a are made of the same material. or different materials. In addition, the lithium ion conductive polymer material 16b inserted between the negative electrode active materials 16a and the lithium ion conductive polymer material 13b inserted between the positive electrode active materials 13a may be the same material or different materials. .

Further, a conductive aid such as acetylene black may be dispersed in the lithium ion conductive polymer material 16 b of the negative electrode active material layer 16 .

<Negative electrode side solid electrolyte dispersed polymer layer>
In this embodiment, a solid electrolyte dispersed polymer layer in which oxide solid electrolyte particles 15a are dispersed in a lithium ion conductive polymer material 15b between the negative electrode active material layer 16 and the oxide solid electrolyte layer 11 A negative electrode-side solid electrolyte-dispersed polymer layer 15 is interposed. As the lithium ion conductive polymer material 15b forming the negative electrode-side solid electrolyte dispersed polymer layer 15, materials that can be used for the lithium ion conductive polymer material 11b can be mentioned.

As the oxide solid electrolyte constituting the oxide solid electrolyte particles 15a of the negative electrode-side solid electrolyte-dispersed polymer layer 15, an oxide solid electrolyte that can be used for the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 can include oxide solid electrolytes similar to . From the viewpoint of reducing contact resistance, the oxide solid electrolyte particles 15a of the negative electrode-side solid electrolyte-dispersed polymer layer 15 and the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 are made of the same oxide solid electrolyte. preferable. Further, the oxide solid electrolyte particles 15a of the negative electrode-side solid electrolyte-dispersed polymer layer 15 and the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 may be made of different oxide solid electrolytes. In this case, for example, LATP is used for the oxide solid electrolyte constituting the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11, and the oxide solid electrolyte particles 15a of the negative electrode-side solid electrolyte-dispersed polymer layer 15 are LAGP and LLZO are used for the constituent oxide solid electrolyte. With such a combination, reduction resistance at the negative electrode can be improved.

Further, the particle size of the oxide solid electrolyte particles 15 a of the negative electrode-side solid electrolyte dispersed polymer layer 15 may be the same as the particle size of the oxide solid electrolyte particles 11 a of the oxide solid electrolyte layer 11 . However, the particle size of oxide solid electrolyte particles 15 a in negative electrode-side solid electrolyte-dispersed polymer layer 15 may differ from the particle size of oxide solid electrolyte particles 11 a in oxide solid electrolyte layer 11 . For example, if the particle size of the oxide solid electrolyte particles 15a of the negative electrode-side solid electrolyte dispersed polymer layer 15 is smaller than the particle size of the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11, the negative electrode-side solid electrolyte dispersion height This is preferable because the molecular layer 15 can be made thinner and the resistance of the all-solid lithium secondary battery 1 can be reduced. Further, when forming the negative electrode-side solid electrolyte-dispersed polymer layer 15 by coating as described later, the oxide solid electrolyte particles 15a are placed between the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 to provide lithium ion conductivity. It can be embedded with polymeric material 15b. However, the particle size of oxide solid electrolyte particles 15 a in negative electrode-side solid electrolyte-dispersed polymer layer 15 may be larger than the particle size of oxide solid electrolyte particles 11 a in oxide solid electrolyte layer 11 .

The average thickness of the negative electrode-side solid electrolyte-dispersed polymer layer 15 may be smaller than the particle size of the oxide solid electrolyte particles 15a. In this case, the negative electrode-side solid electrolyte-dispersed polymer layer 15 is thicker at portions where the oxide solid electrolyte particles 15a are located, and is thinner at portions where the oxide solid electrolyte particles 15a are not located. Therefore, the oxide solid electrolyte particles 15a easily come into contact with the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 and the positive electrode active material 13a.

Moreover, in the negative electrode-side solid electrolyte-dispersed polymer layer 15, the volume ratio of the oxide solid electrolyte particles 15a is preferably larger than the volume ratio of the lithium ion conductive polymer material 15b. By doing so, the resistance of the anode-side solid electrolyte-dispersed polymer layer 15 can be further reduced.

In this embodiment, the oxide solid electrolyte layer 11 and the anode-side solid electrolyte-dispersed polymer layer 15 are integrated, and the anode active material layer 16 and the anode-side solid electrolyte-dispersed polymer layer 15 are integrated. , the oxide solid electrolyte layer 11 and the negative electrode active material layer 16 are integrated with the negative electrode side solid electrolyte dispersed polymer layer 15 interposed therebetween. Therefore, when the oxide solid electrolyte layer 11 and the negative electrode active material layer 16 are separated, breakage occurs.

It should be noted that the lithium ion conductive polymer material 15b constituting the negative electrode-side solid electrolyte dispersed polymer layer 15 and the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a are made of the same material. , is preferable from the viewpoint that the integration strength between the negative electrode-side solid electrolyte-dispersed polymer layer 15 and the oxide solid electrolyte layer 11 can be increased. In this case, it is also preferable from the viewpoint that the negative electrode-side solid electrolyte-dispersed polymer layer 15 and the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a can be simultaneously formed by coating. However, even if the lithium ion conductive polymer material 15b of the negative electrode-side solid electrolyte dispersed polymer layer 15 and the lithium ion conductive polymer material 11b interposed between the oxide solid electrolyte particles 11a are the same material. A negative electrode-side solid electrolyte-dispersed polymer layer 15 may be provided on the negative electrode-side surface of the oxide solid electrolyte layer 11 in which the lithium ion conductive polymer material 11b is inserted between the oxide solid electrolyte particles 11a. Further, the lithium ion conductive polymer material constituting the negative electrode-side solid electrolyte dispersed polymer layer 15 and the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a may be different materials. . In this case, for example, PVDF, SBR, acrylate, or the like can be appropriately used as the lithium ion conductive polymer material constituting the anode-side solid electrolyte-dispersed polymer layer 15. PEO is preferably used as the conductive polymer material 11b.

Further, the lithium ion conductive polymer material forming the negative electrode side solid electrolyte dispersed polymer layer 15 and the lithium ion conductive polymer material 16b inserted between the negative electrode active materials 16a are made of the same material. This is preferable from the viewpoint that the integration strength between the solid electrolyte-dispersed polymer layer 15 and the negative electrode active material layer 16 can be increased. Also, the lithium ion conductive polymer material forming the negative electrode-side solid electrolyte dispersed polymer layer 15 and the lithium ion conductive polymer material 16b inserted between the negative electrode active materials 16a may be different materials. In this case, for example, PVDF is used as the lithium ion conductive polymer material constituting the negative electrode side solid electrolyte dispersed polymer layer 15, and PEO and PEO are used as the lithium ion conductive polymer material 13b that enters between the negative electrode active materials 16a. Preferably a mixture of PVDF is used. With such a combination, the degree of adhesion between the negative electrode-side solid electrolyte-dispersed polymer layer 15 and the negative electrode active material layer 16 can be improved.

<Negative electrode current collector layer>
The negative electrode collector layer 17 is arranged on the side of the negative electrode active material layer 16 opposite to the oxide solid electrolyte layer 11 side, and is integrated with the negative electrode active material layer 16 . Examples of the material of the negative electrode current collector layer 17 include the same materials as those of the positive electrode current collector layer 14 .

<Packaging material>
The packaging material 10 includes a positive electrode current collector layer 14, a positive electrode active material layer 13, a positive electrode side solid electrolyte dispersed polymer layer 12, an oxide solid electrolyte layer 11, a negative electrode side solid electrolyte dispersed polymer layer 15, and a negative electrode active material layer 16. , and the negative electrode current collector layer 17 are accommodated and sealed. Part of the positive electrode current collector layer 14 and the negative electrode current collector layer 17 are led out of the packaging material 10 as electrodes.

The structure of the packaging material 10 is not particularly limited as long as it suppresses the intrusion of external oxygen, moisture, etc. into the area surrounded by the packaging material 10 and does not conduct with the area. A foil laminated with a resin layer can be used.

As described above, the all-solid-state lithium secondary battery 1 of the present embodiment uses an oxide solid electrolyte, and unlike sulfides, even if oxides react with water, it is difficult to generate gases such as hydrogen sulfide that require careful handling. Therefore, it is easy to handle. Further, in the all-solid lithium secondary battery 1 of the present embodiment, the positive electrode active material layer 13, the negative electrode active material layer 16, the positive electrode side solid electrolyte dispersed polymer layer 12, and the negative electrode side solid electrolyte dispersed polymer layer 15 , and the oxide solid electrolyte layer 11 are so integrated that they cannot be separated from each other. The resistance between each layer that is integrated in this way is lower than the resistance between the layers that are not integrated and are simply placed adjacent to each other.

Further, in the all-solid lithium secondary battery 1 of the present embodiment, the positive electrode-side solid electrolyte-dispersed polymer layer 12 interposed between the positive electrode current collector layer 14 and the oxide solid electrolyte layer 11 has high lithium ion conductivity. The oxide solid electrolyte particles 12a are dispersed in the molecular material 12b. Further, in the all-solid lithium secondary battery 1 of the present embodiment, the negative electrode-side solid electrolyte-dispersed polymer layer 15 interposed between the negative electrode active material layer 16 and the oxide solid electrolyte layer 11 is a lithium ion conductive polymer. The oxide solid electrolyte particles 15a are dispersed in the material 15b. In general, oxide solid electrolyte particles have higher lithium ion conductivity than lithium ion conductive polymer materials. It is higher than a layer consisting only of ion-conducting polymer material. Therefore, the positive electrode-side solid electrolyte-dispersed polymer layer 12 and the negative electrode-side solid electrolyte-dispersed polymer layer 15 of this embodiment are located between the positive electrode active material layer 13 and the oxide solid electrolyte layer 11 and between the negative electrode active material layer 16 and the oxide solid electrolyte layer 11 can be formed thicker than in the case where a layer composed only of a lithium ion conductive polymer material is arranged. Therefore, it is possible to prevent the internal resistance from increasing due to the inability to fill the gaps between the positive electrode active material layer 13 and the negative electrode active material layer 16 and the oxide solid electrolyte layer 11 .

As described above, according to the all-solid-state lithium secondary battery 1 of the present embodiment, the internal resistance is reduced and a large current can be achieved.

Next, a method for manufacturing the all-solid lithium secondary battery 1 of this embodiment will be described.

FIG. 4 is a flow chart of a method for manufacturing the all-solid lithium secondary battery 1 according to the embodiment. As shown in FIG. 4, the manufacturing method of the all-solid lithium secondary battery 1 of this embodiment includes a preparation process P1, an arrangement process P2, an integration process P3, and a sealing process P4.

<Preparation process P1>
This step is a step of mainly preparing the oxide solid electrolyte layer 11, the positive electrode active material layer 13, the positive electrode current collector layer 14, the negative electrode active material layer 16, and the negative electrode current collector layer 17. . FIG. 5 is a diagram showing the state of the preparation process.

(Preparation of oxide solid electrolyte layer)
In preparing the oxide solid electrolyte layer 11, first, a green sheet in which the oxide solid electrolyte particles 11a are dispersed in a binder is prepared, and then fired to integrate the oxide solid electrolyte particles 11a. A porous sheet-like member that becomes the oxide solid electrolyte layer 11 is obtained. Alternatively, the oxide solid electrolyte particles 11a may be placed in a mold, molded into a sheet, and then baked under a predetermined pressure to obtain a porous sheet-like member that becomes the oxide solid electrolyte layer 11. good. Alternatively, after the oxide solid electrolyte particles 11a are dispersed in a binder, they may be molded into a sheet shape and the binder may be hardened. In addition, the binder may be made of the lithium ion conductive polymer material 11b. Alternatively, the binder may not be made of the lithium ion conductive polymer material 11b, but in the present embodiment, the lithium ion conductive polymer material 11b enters between the oxide solid electrolyte particles 11a. In this case, the amount of the binder is such that voids are formed between the oxide solid electrolyte particles 11a. Thus, a sheet-like member containing oxide solid electrolyte particles 11a is obtained.

Next, a dispersion liquid in which oxide solid electrolyte particles are dispersed in a lithium ion conductive polymer material is applied to both surfaces of the sheet member containing the oxide solid electrolyte particles 11a and solidified. At this time, the applied lithium ion conductive polymer material enters between the oxide solid electrolyte particles 11a to form the lithium ion conductive polymer material 11b arranged between the oxide solid electrolyte particles 11a. In this way, the oxide solid electrolyte layer 11 in which the lithium ion conductive polymer material 11b enters between the oxide solid electrolyte particles 11a shown in FIG. 5 is obtained. At this time, it is more preferable that the oxide solid electrolyte particles in the dispersion enter between the oxide solid electrolyte particles 11a from the viewpoint of reducing the resistance. In this case, if the particle size of the oxide solid electrolyte particles in the dispersion is smaller than the particle size of the oxide solid electrolyte particles 11a of the sheet-shaped member, the oxide solid electrolyte particles in the dispersion will be the oxide solid electrolyte particles 11a. It is preferable because it is easy to get in between. After the oxide solid electrolyte particles 11a are dispersed in the binder made of the lithium ion conductive polymer material 11b as described above, the sheet-shaped member is molded into a sheet shape and the binder is hardened. In the case of , the lithium ion conductive polymer material 11b is embedded between the oxide solid electrolyte particles 11a before the coating, so that the lithium ion conductive polymer material 11b applied between the oxide solid electrolyte particles 11a by the coating is Polymeric material may not enter.

Further, in this embodiment, when the lithium ion conductive polymer material is applied to both surfaces of the sheet-like member made of the oxide solid electrolyte particles 11a, the lithium ion conductive polymer is applied to both surfaces of the sheet-like member. Apply the lithium ion conductive polymeric material to the extent that the material forms a layer. As a result, the lithium ion conductive polymer material on one side of the oxide solid electrolyte layer 11 solidifies to form the positive electrode side solid electrolyte dispersed polymer layer 12 shown in FIG. The lithium ion conductive polymer material on the surface is solidified to form the anode-side solid electrolyte-dispersed polymer layer 15 shown in FIG.

(Preparation of positive electrode active material layer and positive electrode current collector)
In the preparation of the positive electrode active material layer and the positive electrode current collector, the positive electrode active material 13a and, if necessary, a conductive aid are dispersed in the lithium ion conductive polymer material 13b, and the positive electrode current collector layer 14 is coated with the positive electrode active material 13a. Apply to and dry. Thus, the cathode active material layer 13 is provided on the cathode current collector layer 14 .

(Preparation of negative electrode active material layer and negative electrode current collector)
In the preparation of the negative electrode active material layer and the negative electrode current collector, the negative electrode active material 16a and a conductive aid as necessary are dispersed in the lithium ion conductive polymer material 16b, and are dispersed on the negative electrode current collector layer 17. Apply to and dry. Thus, the negative electrode active material layer 16 is provided on the negative electrode current collector layer 17 .

<Placement process P2>
FIG. 6 is a diagram showing the state of this process. As shown in FIG. 6, after the preparation step P1, a laminate of the positive electrode active material layer 13 and the positive electrode current collector layer 14 is placed on one side of the oxide solid electrolyte layer 11 so that the positive electrode active material layer 13 is a solid oxide. It is arranged so as to face the electrolyte layer 11 side. However, since the positive electrode-side solid electrolyte-dispersed polymer layer 12 is positioned on one surface of the oxide solid electrolyte layer 11 as described above, the positive electrode active material layer 13 is formed on the positive electrode-side solid electrolyte-dispersed polymer layer 12. placed in

Also, the laminate of the negative electrode active material layer 16 and the negative electrode current collector layer 17 is arranged on the other surface side of the oxide solid electrolyte layer 11 so that the negative electrode active material layer 16 faces the oxide solid electrolyte layer 11 side. However, since the negative electrode-side solid electrolyte-dispersed polymer layer 15 is positioned on the other surface of the oxide solid electrolyte layer 11 as described above, the negative electrode active material layer 16 is formed on the negative electrode-side solid electrolyte-dispersed polymer layer 15. placed in

In this way, as shown in FIG. 6, an oxide solid electrolyte layer 11, a positive electrode-side solid electrolyte-dispersed polymer layer 12, a positive electrode active material layer 13, a positive electrode current collector layer 14, a negative electrode-side solid electrolyte-dispersed polymer layer 15, and a negative electrode are formed. A battery body 1b in which the active material layer 16 and the negative electrode current collector layer 17 are laminated is obtained.

<Integration process P3>
After the placement step P2, the laminated oxide solid electrolyte layer 11, positive electrode-side solid electrolyte-dispersed polymer layer 12, positive electrode active material layer 13, positive electrode current collector layer 14, negative electrode-side solid electrolyte-dispersed polymer layer 15, and negative electrode The active material layer 16 and the negative electrode current collector layer 17 are integrated. The oxide solid electrolyte layer 11, the positive electrode-side solid electrolyte-dispersed polymer layer 12, and the negative electrode-side solid electrolyte-dispersed polymer layer 15 have already been integrated, and the positive electrode active material layer 13 and the positive electrode current collector layer 14 are integrated. The negative electrode active material layer 16 and the negative electrode current collector layer 17 are integrated. Therefore, in this step, the positive electrode side solid electrolyte dispersed polymer layer 12 and the positive electrode active material layer 13 are integrated, and the negative electrode side solid electrolyte dispersed polymer layer 15 and the negative electrode active material layer 16 are integrated.

FIG. 7 is a diagram showing this process. As shown in FIG. 7, in this embodiment, integration is performed by hot pressing. Specifically, the battery body 1b is sandwiched between a pair of heated hot press dies 21 and 22 . Then, the hot press molds 21 and 22 are pressed while being heated. At this time, the temperature of the hot press dies 21 and 22 is higher than the temperature at which the lithium ion conductive polymer material constituting the positive electrode side solid electrolyte dispersed polymer layer 12 and the negative electrode side solid electrolyte dispersed polymer layer 15 softens. Preferably. For example, if the lithium ion conductive polymer material is PEO, the softening temperature is approximately 100° C., so the temperature of the hot press dies 21 and 22 is preferably higher than this temperature. Further, for example, when the lithium ion conductive polymer material is PEO as described above, setting the temperature to 130° C. or less increases the fluidity, so that the lithium ion conductive polymer material flows out. is preferable from the viewpoint of suppressing Further, for example, when the lithium ion conductive polymer material is PEO as described above, the temperature of the heat press molds 21 and 22 is more preferably between 110°C and 120°C. Further, the pressure for pressing the battery body 1b is preferably, for example, 1 MPa or more and 50 MPa or less, from the viewpoint of suppressing the outflow of the lithium ion conductive polymer material while firmly integrating each layer.

Further, in this step, a part of the lithium ion conductive polymer material constituting the positive electrode side solid electrolyte dispersed polymer layer 12 may enter into the positive electrode active material layer 13, and the negative electrode side solid electrolyte dispersed polymer layer 15 may be formed. Part of the constituent lithium ion conductive polymer material may enter into the negative electrode active material layer 16 .

In this way, the positive electrode-side solid electrolyte-dispersed polymer layer 12 and the positive electrode active material layer 13 are integrated, and the negative electrode-side solid electrolyte-dispersed polymer layer 15 and the negative electrode active material layer 16 are integrated. A battery body 1b in the material 10 is obtained.

<Sealing step P4>
Next, the integrated battery body 1b is arranged in the packaging material 10, and the packaging material 10 is sealed. It is preferable that heat sealing or the like be used for the sealing.

Thus, the all-solid lithium secondary battery 1 shown in FIG. 1 is obtained.

As described above, according to the method for manufacturing the all-solid lithium secondary battery 1 of the present embodiment, the positive electrode active material layer 13, the negative electrode active material layer 16, and the oxide solid electrolyte layer 11 are integrated. Therefore, an easily handled oxide solid electrolyte is used, and the resistance between the positive electrode active material layer 13 and the oxide solid electrolyte layer 11 and between the negative electrode active material layer 16 and the oxide solid electrolyte layer 11 is It is possible to manufacture an all-solid-state lithium secondary battery 1 that is reduced and can achieve a large current.

Further, in the present embodiment, the integration step P3 is performed by thermocompression bonding. Therefore, for example, the integration process P3 can be performed more easily than when the integration process P3 is performed using ultrasonic waves.

Although the present invention has been described above using the embodiments as examples, the present invention is not limited to these.

For example, in the above-described embodiment, in the oxide solid electrolyte layer 11, the lithium ion conductive polymer material 11b enters at least partly between the oxide solid electrolyte particles 11a. However, in the present invention, as long as the oxide solid electrolyte layer 11 has lithium ion conductivity, the oxide solid electrolyte layer 11 may not have the lithium ion conductive polymeric material 11b. However, from the viewpoint of maintaining good lithium ion conductivity of the oxide solid electrolyte layer 11, it is preferable that the lithium ion conductive polymer material 11b enter at least part of the spaces between the oxide solid electrolyte particles 11a.

In addition, the lithium ion conductive polymer material 12b forming the positive electrode side solid electrolyte dispersed polymer layer 12, the lithium ion conductive polymer material 15b forming the negative electrode side solid electrolyte dispersed polymer layer 15, and the oxide solid electrolyte particles 11a. A material different from the lithium ion conductive polymer material 11b that enters between the particles of the . In this case, in the preparation step P1, when the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a is applied, the lithium ion conductive polymer material 11b is applied to the oxide solid electrolyte particles 11a. The oxide solid electrolyte layer 11 is obtained by coating the sheet member so as not to form a layer. Then, a lithium ion conductive polymer material that becomes the positive electrode side solid electrolyte dispersed polymer layer 12 and the negative electrode side solid electrolyte dispersed polymer layer 15 may be applied on the obtained oxide solid electrolyte layer 11 .

In addition, the lithium ion conductive polymer material 13b may not enter between the positive electrode active materials 13a of the positive electrode active material layer 13, and the lithium ion conductive polymer material may not enter between the negative electrode active materials 16a of the negative electrode active material layer 16. 16b may not be included.

In addition, in the above embodiment, the integration step P3 is performed by thermocompression bonding, but the integration step P3 may be performed by a method other than thermocompression bonding such as ultrasonic fusion bonding.

Next, the polymer arranged between the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11 is a polymer having lithium ion conductivity, and lithium salt is dispersed in the polymer. I checked the amount of salt.

(Example 1)
In order to produce the battery body 1b, a laminate was prepared in which solid electrolyte dispersed polymer layers were provided on both sides of the oxide solid electrolyte layer 11 . In this preparation, first, a porous oxide solid electrolyte particle bonding layer to which the oxide solid electrolyte particles 11a were bonded was prepared. The oxide solid electrolyte particles consist of LLZO.

Next, a coating liquid composed of a lithium ion conductive polymer material in which oxide solid electrolyte particles and a lithium salt are dispersed was applied to both surfaces of the oxide solid electrolyte particle bonding layer. PEO was used as the lithium ion conductive polymer material, LiFSI was used as the lithium salt, and LLZO particles were used as the oxide solid electrolyte particles. Also, the weight ratio of PEO and LiFSI was set to 1:1. This coating allows at least the lithium ion conductive polymer material and the lithium salt to enter between the oxide solid electrolyte particles in the oxide solid electrolyte particle bonding layer, thereby forming the oxide solid electrolyte layer 11 shown in FIGS. A positive electrode-side solid electrolyte-dispersed polymer layer 12 was prepared from a layer made of a coating solution formed on one surface of oxide solid electrolyte layer 11 , and formed on the other surface of oxide solid electrolyte layer 11 . A negative electrode-side solid electrolyte-dispersed polymer layer 15 was produced from a layer made of the coating liquid.

Also, a laminate was prepared in which the positive electrode active material layer 13 was provided on one surface of the positive electrode current collector layer 14 . Specifically, an aluminum foil is used as the positive electrode current collector layer 14, and lithium nickelate (NCA), carbon black, acrylate, and carboxymethyl cellulose (CMC) are dispersed on one surface of the positive electrode current collector layer 14. The resulting solution was applied and dried to obtain the positive electrode active material layer 13, thereby forming the laminate.

Also, a laminate was prepared in which the negative electrode active material layer 16 was provided on one surface of the negative electrode current collector layer 17 . Specifically, a copper foil is used as the negative electrode current collector layer 17, and graphitizable carbon, a styrene-butadiene block copolymer (SBR), and CMC are dispersed on one surface of the negative electrode current collector layer 17. By applying and drying the solution, the negative electrode active material layer 16 was obtained, and the laminate was obtained.

Next, the above three laminates were superimposed and integrated. Specifically, the positive electrode-side solid electrolyte-dispersed polymer layer 12 provided on one surface of the oxide solid electrolyte layer 11 and the positive electrode active material layer 13 provided on one surface of the positive electrode current collector layer 14 are superimposed to form the negative electrode-side solid electrolyte-dispersed polymer layer 15 provided on the other surface of the oxide solid electrolyte layer 11 and the negative electrode active material layer 16 provided on one surface of the negative electrode current collector layer 17. superimposed. Next, the superimposed laminate was integrated by thermocompression bonding.

Thus, a battery body 1b was obtained.

Next, an AC voltage was applied to the positive electrode current collector layer 14 and the negative electrode current collector layer 17 of the battery body 1b while sweeping the frequency, and impedance was measured. A Cole-Cole plot of the results is shown in FIG. In FIG. 8, the horizontal axis indicates the resistance component, and the vertical axis indicates the reactance component. As a result, the resistance of the battery body of Example 1 was approximately 50Ω.

(Example 2)
A battery body 1b was produced in the same manner as in Example 1, except that the weight ratio of PEO and LiFSI was 4:1. When PEO and LiFSI are used in a general all-solid lithium secondary battery other than the present invention, the weight ratio is the same as in this example. Impedance measurement was performed in the same manner as in Example 1 for this battery body 1b. A Cole-Cole plot of the results is shown in FIG. As a result, the resistance of the battery body of the reference example was approximately 2000Ω.

Although the resistance of Example 2 is sufficiently low for practical use, the resistance of Example 1 was approximately 1/40 of the resistance of Example 2. Therefore, the lithium ion concentration of the lithium ion conductive polymer material 11b entering between the oxide solid electrolyte particles 11a of the oxide solid electrolyte layer 11, the positive electrode side solid electrolyte dispersed polymer layer 12, and the lithium ion conductive polymer material 13b It has been found that when the molecular material is PEO and LiFSI is dispersed in the lithium ion polymer material, the weight of LiFSI relative to PEO is preferably 1 or more times.

Note that if the weight of LiFSI relative to PEO is more than twice the weight, there is concern about strength, so the weight of LiFSI relative to PEO is preferably at most twice the weight.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, an all-solid lithium secondary battery that is easy to handle and can achieve a large current and a method for manufacturing an all-solid lithium secondary battery are provided, and are used for automobile batteries and industrial equipment. It is expected to be used in fields such as batteries and batteries for consumer electronics.

Claims (7)

an oxide solid electrolyte layer containing oxide solid electrolyte particles having lithium ion conductivity and a lithium ion conductive polymer material having lithium ion conductivity entering between the oxide solid electrolyte particles;
a positive electrode active material layer disposed on one side of the oxide solid electrolyte layer;
a negative electrode active material layer disposed on the other surface side of the oxide solid electrolyte layer;
The oxide solid electrolyte particles are dispersed in a lithium ion conductive polymer material having lithium ion conductivity, which is disposed between the positive electrode active material layer and the negative electrode active material layer and the oxide solid electrolyte layer. a solid electrolyte dispersed polymer layer;
with
The positive electrode active material layer, the negative electrode active material layer, the solid electrolyte dispersed polymer layer, and the oxide solid electrolyte layer are integrated ,
the lithium ion conductive polymer material entering between the oxide solid electrolyte particles of the oxide solid electrolyte layer and the lithium ion conductive polymer material of the solid electrolyte dispersed polymer layer are the same material,
Lithium salt is dispersed in each of the lithium ion conductive polymer material of the oxide solid electrolyte layer and the lithium ion conductive polymer material of the solid electrolyte dispersed polymer layer,
The lithium ion conductive polymer material of the oxide solid electrolyte layer and the lithium ion conductive polymer material of the solid electrolyte dispersed polymer layer are polyethylene oxide,
The lithium salt is lithium bis(fluorosulfonyl)imide,
The weight of the lithium salt is 1 to 2 times the weight of the lithium ion conductive polymer material.
An all-solid lithium secondary battery characterized by: an oxide solid electrolyte layer containing oxide solid electrolyte particles having lithium ion conductivity and a lithium ion conductive polymer material having lithium ion conductivity entering between the oxide solid electrolyte particles;
a positive electrode active material layer disposed on one side of the oxide solid electrolyte layer;
a negative electrode active material layer disposed on the other surface side of the oxide solid electrolyte layer;
The oxide solid electrolyte particles are disposed between at least one of the positive electrode active material layer and the negative electrode active material layer and the oxide solid electrolyte layer, and the lithium ion conductive polymer material having lithium ion conductivity contains the oxide solid electrolyte particles. a solid electrolyte-dispersed polymer layer to be dispersed;
with
The positive electrode active material layer, the negative electrode active material layer, the solid electrolyte dispersed polymer layer, and the oxide solid electrolyte layer are integrated ,
The lithium ion conductive polymer material that enters between the oxide solid electrolyte particles of the oxide solid electrolyte layer and the lithium ion conductive polymer material of the solid electrolyte dispersed polymer layer are different materials.
An all-solid lithium secondary battery characterized by: 3. The method according to claim 1, wherein the particle size of the oxide solid electrolyte particles of the solid electrolyte-dispersed polymer layer is smaller than the particle size of the oxide solid electrolyte particles of the oxide solid electrolyte layer. All-solid-state lithium secondary battery. an oxide solid electrolyte layer containing oxide solid electrolyte particles having lithium ion conductivity;
a positive electrode active material layer disposed on one side of the oxide solid electrolyte layer;
a negative electrode active material layer disposed on the other surface side of the oxide solid electrolyte layer;
The oxide solid electrolyte particles are disposed between at least one of the positive electrode active material layer and the negative electrode active material layer and the oxide solid electrolyte layer, and the lithium ion conductive polymer material having lithium ion conductivity contains the oxide solid electrolyte particles. a solid electrolyte-dispersed polymer layer to be dispersed;
with
The positive electrode active material layer, the negative electrode active material layer, the solid electrolyte dispersed polymer layer, and the oxide solid electrolyte layer are integrated ,
The particle size of the oxide solid electrolyte particles in the solid electrolyte dispersed polymer layer is smaller than the particle size of the oxide solid electrolyte particles in the oxide solid electrolyte layer.
An all-solid lithium secondary battery characterized by: 5. The method according to claim 4 , wherein the lithium ion conductive polymer material of the solid electrolyte-dispersed polymer layer is intruded into at least a portion between the oxide solid electrolyte particles of the oxide solid electrolyte layer. All-solid lithium secondary battery. The oxide solid electrolyte layer further has a lithium ion conductive polymer material that enters between the oxide solid electrolyte particles,
The lithium ion conductive polymer material entering between the oxide solid electrolyte particles of the oxide solid electrolyte layer and the lithium ion conductive polymer material of the solid electrolyte dispersed polymer layer are the same material. The all-solid lithium secondary battery according to claim 4 . the solid electrolyte dispersed polymer layer is disposed between the positive electrode active material layer and the negative electrode active material layer and the oxide solid electrolyte layer;
Lithium salt is dispersed in each of the lithium ion conductive polymer material of the oxide solid electrolyte layer and the lithium ion conductive polymer material of the solid electrolyte dispersed polymer layer,
The lithium ion conductive polymer material of the oxide solid electrolyte layer and the lithium ion conductive polymer material of the solid electrolyte dispersed polymer layer are polyethylene oxide,
The lithium salt is lithium bis(fluorosulfonyl)imide,
7. The all-solid lithium secondary battery according to claim 6 , wherein the weight of the lithium salt is 1 to 2 times the weight of the lithium ion conductive polymer material.

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