JP7660808B2 - All-solid-state chloride ion battery and method for producing same - Google Patents

Description

Patent Law Article 30, Paragraph 2 Applies Patent Law Article 30, Paragraph 2 Applies, 61st Battery Symposium Koen Proceedings, Disclosure of All-Solid-State Chloride Ion Battery and Its Manufacturing Method by Inventor (November 11, 2020)

Patent Law Article 30, Paragraph 2 Applies Patent Law Article 30, Paragraph 2 Applies, 61st Battery Symposium (online symposium), Inventor discloses all-solid-state chloride ion battery and its manufacturing method (November 20, 2020)

The present invention relates to an all-solid-state chloride ion battery and a method for manufacturing the same.

Lithium ion batteries use Li ⁺ as a carrier and are characterized by their high voltage. On the other hand, halide ion batteries that use halide ions such as F ^- as a carrier are said to have theoretically 1.5 to 3 times the energy density of current lithium ion batteries, and are expected to be a promising candidate for post-lithium ion batteries. Among them, chloride ion batteries, which use chlorides, which are abundant resources, also have the advantage of excellent cost performance.

For example, Non-Patent Document 1 reports cubic perovskite-type CsSnCl ₃ as a solid electrolyte that exhibits high ^Cl ion conductivity of 10 ⁻⁴ S/cm or more near room temperature.

K. Yamada Y. Kuranaga, K. Ueda, S. Goto, T. Okuda, and Y. Furukawa, “Phase Transition and Electric Conductivity of ASnCl3 (A = Cs and CH3NH3)”, Bull. Chem. Soc. Jpn., 1998, 71, pp.127-134.

Since chlorides have a low Young's modulus and excellent plasticity, it is possible that excellent battery characteristics and cycle stability can be achieved by making them into an all-solid-state battery. However, few solid electrolytes are known that exhibit high chloride ion conductivity near room temperature. In addition, CsSnCl ₃ described in Non-Patent Document 1 undergoes a phase transition from a monoclinic to a cubic perovskite structure having high Cl ^-ion conductivity when heated to around 120 ° C. Thereafter, when the temperature is lowered, the cubic perovskite structure is maintained up to 40 ° C., but when the temperature is further lowered, the structure returns to the original monoclinic structure, ^and high Cl -ion conductivity cannot be maintained at room temperature, resulting in a problem of structural stability that makes the room temperature operation of the battery unstable.

In view of the above problems, the present invention aims to provide an all-solid-state chloride ion battery that operates stably near room temperature, exhibits high chloride ion conductivity, and can be charged and discharged near room temperature, and a method for manufacturing the same.

In order to achieve the above object, one aspect of the present invention is an all-solid-state chloride ion battery including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, the solid electrolyte layer containing a compound represented by CsSn _1-X Mn _X Cl ₃ (wherein X is a number satisfying 0<X<1).

In addition, as another aspect, the present invention provides a method for producing an all-solid-state chloride ion battery, the method including the steps of: subjecting a mixture containing CsCl, _SnCl2 , and _MnCl2 to a mechanical milling process to obtain a solid electrolyte; and pressing a positive electrode material and a negative electrode material with the solid electrolyte disposed between them to obtain an all-solid-state chloride ion battery including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer.

Thus, according to the present invention, by using a compound represented _by CsSn1 _{- XMnXCl3} in which part of the Sn2 ⁺ sites of _CsSnCl3 are substituted and doped with Mn2 ⁺ as a solid electrolyte and configuring an all-solid-state chloride ion battery, it is possible to provide an all-solid-state chloride ion battery that operates stably near room temperature, exhibits high chloride ion conductivity, and is capable of being charged and discharged near room temperature, as well as a method for producing the same.

1 is a cross-sectional view showing a schematic diagram of an embodiment of an all-solid-state chloride ion battery according to the present invention. FIG. 1 is a flow chart showing a part of an embodiment of a method for producing an all-solid-state chloride ion battery according to the present invention. 1 shows XRD patterns of a compound of a solid electrolyte used in an all-solid-state chloride ion battery according to the present invention and a reference compound. 1 is a chart showing the results of examining the crystal structures of a compound of a solid electrolyte used in an all-solid-state chloride ion battery according to the present invention and a reference compound by a differential scanning calorimeter (DSC). FIG. 2 is an exploded perspective view showing a schematic diagram of an HS cell used in an AC impedance test. FIG. 6 is a cross-sectional view showing a schematic diagram of a sample inserted into the HS cell of FIG. 5 . 1 is a graph showing the results of an AC impedance test. FIG. 2 is an exploded perspective view showing a typical example of a PEEK cell used in a charge/discharge test. 1 is a graph showing a charge/discharge profile at 30° C. of the all-solid-state chloride ion battery of the example. 1 is a graph showing a charge/discharge profile at 100° C. of the all-solid-state chloride ion battery of the example.

Below, an embodiment of the all-solid-state chloride ion battery and its manufacturing method according to the present invention will be described in detail with reference to the attached drawings.

As shown in Fig. 1, the all-solid-state chloride ion battery 10 of this embodiment includes a positive electrode layer 13, a negative electrode layer 11, and a solid electrolyte layer ₁₂ disposed between the positive electrode layer and the negative electrode layer. The solid electrolyte layer 12 includes a compound represented by CsSn1 _{- XMnXCl3} (wherein X is a number satisfying 0<X<1). Optionally, the battery may further include a protective layer 14 on the outside of the positive electrode layer, i.e., on the side opposite to the solid electrolyte layer. Each layer will be described in detail.

The solid electrolyte layer 12 contains a compound represented _by CsSn1 _{- XMnXCl3} as a solid electrolyte, which is obtained by doping some of the Sn2 ⁺ sites of _CsSnCl3 with Mn2 ⁺ substitution doping. The cubic perovskite structure _CsSnCl3 is known to exhibit high Cl ^- ion conductivity, but when cooled from a temperature of about 120°C or higher, it undergoes a phase transition to a monoclinic crystal, and has a structural stability defect in that it cannot maintain high Cl ^- ion conductivity at around room temperature. On the other hand, a compound represented by CsSn1 _{- XMnXCl3} in which Mn2 ⁺ is substituted and doped into a part of the _Sn2 ⁺ sites of _CsSnCl3 does not undergo phase transition during either heating or cooling in a temperature range above room temperature, and maintains a stable cubic perovskite structure even near room temperature, and can maintain a high Cl ^- ion conductivity of the order of ^10-4 S/cm, which is equivalent to that of cubic perovskite structure _CsSnCl3 .

In the above formula, X, which represents the amount of substitutional doping of Mn, is preferably a number that satisfies 0<X≦0.2, more preferably a number that satisfies 0<X≦0.1, and even more preferably a number that satisfies 0.01≦X≦0.1.

The solid electrolyte layer 12 is preferably a green compact obtained by pressure molding solid electrolyte particles. The solid electrolyte particles are not sintered, and because they are chlorides, they are a soft material with excellent plasticity. By pressure molding, the particles can adhere to each other and also to the adjacent positive electrode layer 13 and negative electrode layer 11.

The thickness of the solid electrolyte layer 12 is preferably 1 μm or more, and more preferably 100 μm or more. On the other hand, the thickness of the solid electrolyte layer 12 is preferably 1000 μm or less, and more preferably 500 μm or less.

The positive electrode layer 13 includes an electrode mixture containing at least a positive electrode active material. The positive electrode active material is preferably a metal chloride, and examples of the positive electrode active material include chlorides of poor metals such as bismuth chloride (BiCl ₃ ), gallium chloride (GaCl ₃ ), and indium chloride (InCl ₃ ), chlorides of precious metals such as copper chloride (CuCl) and silver chloride (AgCl), chlorides of iron group elements such as nickel chloride (NiCl ₂ ), cobalt chloride (CoCl ₂ ), and iron chloride (FeCl ₂ ), and vanadium chloride (VCl ₃ ).

The electrode mixture of the positive electrode layer 13 generally has low ionic conductivity and may contain a solid electrolyte. As with the solid electrolyte layer 12, the solid electrolyte used for the electrode mixture of the positive electrode layer 13 is preferably a compound represented by CsSn _1-X Mn _X Cl ₃ (wherein X is a number satisfying 0<X<1).

The proportion of solid electrolyte in the electrode mixture of the positive electrode layer 13 is preferably 50 parts by mass or more, and more preferably 100 parts by mass or more, per 100 parts by mass of the positive electrode active material. On the other hand, the proportion of solid electrolyte in the electrode mixture is preferably 200 parts by mass or less, and more preferably 150 parts by mass or less.

The electrode mixture of the positive electrode layer 13 generally does not have electronic conductivity, and may therefore contain a conductive agent. Examples of the conductive agent include carbon materials and metal compounds. Examples of the carbon material include carbon black (e.g., acetylene black, ketjen black, furnace black, etc.), graphite powder, and fibrous carbon materials. Examples of the metal compound include metals, metal alloys, and metal oxides that have electronic conductivity.

In the case of a carbon material, the proportion of the conductive agent in the electrode mixture of the positive electrode layer 13 is preferably 10 parts by mass or more, and more preferably 30 parts by mass or more, per 100 parts by mass of the positive electrode active material. On the other hand, the proportion of the conductive agent in the electrode mixture is preferably 100 parts by mass or less, and more preferably 50 parts by mass or less.

The positive electrode layer 13 is preferably a compact obtained by pressure molding electrode mixture particles. The electrode mixture particles are not sintered, and since they contain chlorides, they are a soft material with excellent plasticity. By pressure molding, the particles can adhere to each other and also to the adjacent solid electrolyte layer 12.

The thickness of the positive electrode layer 13 is preferably 1 μm or more, and more preferably 100 μm or more. On the other hand, the thickness of the positive electrode layer 13 is preferably 1000 μm or less, and more preferably 500 μm or less.

The negative electrode layer 11 contains at least a negative electrode active material. As the negative electrode active material, an active material having a lower potential than the positive electrode active material is used. Examples of such active materials include simple metals such as lead (Pb) and tin (Sn), alloys, oxides thereof, and chlorides thereof.

The negative electrode layer 11 may be a compact obtained by pressure molding negative electrode active material particles, or may be a foil or plate of negative electrode active material. The thickness of the negative electrode layer 11 is preferably 1 μm or more, and more preferably 100 μm or more. On the other hand, the thickness of the negative electrode layer 11 is preferably 1000 μm or less, and more preferably 500 μm or less.

The protective layer 14 is a layer that can be provided arbitrarily, and prevents the contact between the current collector and the electrode mixture and suppresses the reaction between them, thereby further improving the cycle characteristics. The protective layer 14 preferably includes a protective material containing a solid electrolyte and a conductive agent. As with the solid electrolyte layer 12, the solid electrolyte used as the protective material is preferably a compound represented by CsSn _1-X Mn _X Cl ₃ (wherein X is a number satisfying 0<X<1). In addition, as the conductive agent used as the protective material, a carbon material and a metal compound similar to those of the electrode mixture of the positive electrode layer 13 may be used.

The protective layer 14 is preferably a green compact obtained by pressure molding protective material particles. Since the protective layer 14 does not affect the charge/discharge capacity of the battery, it is preferable that the thickness of the protective layer 14 is thin, preferably 500 μm or less, and more preferably 100 μm or less. There is no particular limit to the lower limit of the thickness, but for example, 1 μm or more is preferable.

In the all-solid-state chloride ion battery 10 having such a configuration, a compound represented by CsSn1 _{-xMnxCl3 is} used for the solid electrolyte of the solid electrolyte layer ₁₂ , so that the battery can stably maintain a cubic perovskite structure even at around room temperature and exhibit a high Cl ^- ion conductivity on the order of ^10-4 S/cm.

Next, a method for manufacturing the all-solid-state chloride ion battery according to the present embodiment will be described. As shown in Fig. 2, the method includes a first mechanical milling step 22 in which CsCl, _SnCl2 , and _MnCl2 are mixed as three raw materials 21a, 21b, and 21c of the solid electrolyte, and the mixture is subjected to mechanical milling to obtain a solid electrolyte 23, and a pressing step (not shown) in which the solid electrolyte 23 is placed between a positive electrode material and a negative electrode material and pressed to obtain an all-solid-state chloride ion battery.

Optionally, the method may further include a second mechanical milling step 25 in which the solid electrolyte 23 and the conductive agent 24 are mixed and the mixture is subjected to a mechanical milling process to obtain a conductive coating material 26 in which the solid electrolyte is coated with the conductive agent. The conductive coating material 26 can be used as a protective material for forming a protective layer, and in the pressing step, the protective material, the positive electrode material, the solid electrolyte, and the negative electrode material are arranged in this order and pressed to obtain an all-solid-state chloride ion battery.

Optionally, the method may further include a third mechanical milling step 28 in which the conductive coating material 26 and the positive electrode active material 27 are mixed and the mixture is subjected to a mechanical milling process to obtain an electrode mixture 29. The electrode mixture 29 is used as a positive electrode material in the pressing step. Each of the above steps will be described in detail.

In the first mechanical milling step 22, first, in order to obtain a compound represented _by CsSn1 _{- XMnXCl3} as a solid electrolyte, the raw materials CsCl, _SnCl2 , and _MnCl2 are mixed to have a desired composition. That is, they are mixed so that the molar ratio of CsCl: _SnCl2 : _MnCl2 is 1:1-X:X. Then, the mixture of powders of CsCl, _SnCl2 , and _MnCl2 is subjected to mechanical milling treatment, thereby obtaining a powder of the compound represented by _{CsSn1- XMnXCl3 .} X is a number satisfying 0<X<1. For example, when X=0.05 as shown in FIG. ₂ , a solid electrolyte 23 of _{CsSn0.95Mn0.05Cl3} can be obtained by mixing CsCl, _SnCl2 , and _MnCl2 in a molar ratio of 1:0.95: _0.05 .

For the mechanical milling process, for example, a ball mill, a vibration mill, a turbo mill, a mechanofusion mill, a disk mill, etc. The rotation speed and processing time of the mechanical milling process may be such that the raw material powders of CsCl, _SnCl2 , and _MnCl2 are each converted into a powder of a compound represented by CsSn1 _{-XMnXCl3 , and} for example, the rotation speed is 400 to 600 rpm and the processing time is 3 to 12 hours.

In the second mechanical milling process 25, first, the solid electrolyte 23 and the conductive agent 24 are mixed. As shown in FIG. 2, the solid electrolyte 23 is preferably the solid electrolyte 23 obtained in the first mechanical milling process 22. Specific examples of the conductive agent 24 and the mixing ratio of the solid electrolyte 23 and the conductive agent 24 are described in the description of the positive electrode layer above, so the description will be omitted here.

Then, the mixture containing the solid electrolyte 23 and the conductive agent 24 is subjected to mechanical milling to obtain the conductive coating material 26. The conductive coating material 26 is a collection of particles in which the surfaces of the solid electrolyte particles are coated with the conductive agent. For example, as shown in FIG. 2, when CsSn _0.95 Mn _0.05 Cl ₃ is used as the solid electrolyte 23 and carbon black (C) is used as the conductive agent 24, a collection of particles in which the surfaces of CsSn _0.95 Mn _0.05 Cl ₃ particles are carbon-coated can be obtained as the conductive coating material 26, which is represented in this specification as CsSn _0.95 Mn _0.05 Cl ₃ /C.

The equipment used for the mechanical milling process is the same as that used for the first mechanical milling process. The rotation speed and processing time of the mechanical milling process may be such that the surface of the solid electrolyte particles is covered with the conductive agent, for example, the rotation speed is 400 to 600 rpm and the processing time is 3 to 12 hours.

In the third mechanical milling process 28, first, the conductive coating material 26 and the positive electrode active material 27 are mixed. As shown in FIG. 2, the conductive coating material 26 obtained in the second mechanical milling process 25 is preferable, but the present invention is not limited to this, and a collection of particles in which particles of other solid electrolytes are coated with other conductive agents may be used. The mixing ratio of the conductive coating material 26 and the positive electrode active material 27 is determined by the ratio of the mass of the solid electrolyte in the conductive coating material 26 to the mass of the positive electrode active material. The ratio of the solid electrolyte to the positive electrode active material and specific examples of the positive electrode active material are described in the description of the positive electrode layer above, so a description thereof will be omitted here.

Then, the mixture containing the conductive coating material 26 and the positive electrode active material 27 is subjected to mechanical milling to obtain an electrode mixture 29. The electrode mixture 29 is a mixture of the conductive coating material and the positive electrode active material. For example, as shown in FIG. 2, when _{CsSn0.95Mn0.05Cl3} / _C is used as the conductive coating material 26 and _bismuth chloride ( _BiCl3 ) is used as the positive _electrode active material 27, the obtained electrode mixture ₂₉ is represented in this specification as _BiCl3 /CsSn0.95Mn0.05Cl3/ _C .

The equipment used for the mechanical milling process is the same as that used in the first mechanical milling process. The rotation speed and processing time of the mechanical milling process may be such that the process is continued until a mixture of the conductive coating material and the positive electrode active material is obtained. For example, the rotation speed is 100 to 400 rpm, and the processing time is 3 to 12 hours. The mechanical milling process may be performed in a dry or wet manner.

In the pressing process (not shown), the positive electrode composite 29 and solid electrolyte 23 obtained above, and the negative electrode material are arranged in this order and pressed to form an all-solid-state chloride ion battery having a positive electrode layer, a solid electrolyte layer, and a negative electrode layer in this order. A negative electrode active material can be used as the negative electrode material. The negative electrode active material is described in the description of the negative electrode layer above, so a description of the negative electrode active material is omitted here. In addition, in order to form an all-solid-state chloride ion battery further comprising a protective layer, the conductive coating material 26 obtained above, the positive electrode composite 29 and solid electrolyte 23, and the negative electrode material are arranged in this order and pressed.

The pressure during pressing may be any pressure that can cause the particles of the solid electrolyte 23 obtained above to undergo plastic deformation and form a dense solid electrolyte layer, and is preferably, for example, 255 to 510 MPa. The temperature during pressing may be room temperature. No heating process such as sintering is required.

According to the manufacturing method of the all-solid-state chloride ion battery using such processes, the solid electrolyte 23, electrode mixture 29, and conductive coating material, which are the materials for the solid electrolyte layer, positive electrode layer, and optional protective layer that make up the battery, can be efficiently obtained, and an all-solid-state chloride ion battery capable of reversible charging and discharging can be obtained through the simple manufacturing process of pressure-molding the constituent materials of the battery. In addition, since there is no need for sintering, it is also possible to avoid high resistance due to side reactions.

[1. Solid electrolyte]
CsCl, SnCl ₂ and MnCl ₂ were enclosed and mixed in a pot in a glove box in an Ar atmosphere at a molar ratio of 1:0.95:0.05 and 1:0.90:0.10, respectively, and the mixture was subjected to mechanical milling treatment for 12 hours at 600 rpm using a planetary ball mill (Premium line P-7, manufactured by Fritch Co., Ltd.). For each sample obtained, an XRD pattern was obtained using an X-ray diffraction (XRD) measuring device (manufactured by Rigaku Co., Ltd., product number: Miniflex600). In addition, an XRD pattern of CsSnCl ₃ of each structure was also obtained for comparison. The results are shown in FIG. 3.

_{From the XRD patterns shown in FIG. 3, it was confirmed that both CsSn0.95Mn0.05Cl3 and CsSn0.9Mn0.1Cl3 obtained} above have a cubic _perovskite structure.

In addition, _{the CsSn0.95Mn0.05Cl3} obtained above _{and CsSnCl3} as a comparative example were heated from near room temperature to 200°C, then cooled to -150°C, and then heated again to near room temperature, and the crystal structures of the above two compounds during this period were examined by a differential scanning calorimeter (DSC). The results are shown in Figure 4.

As shown in Fig. 4, _CsSnCl3 underwent a phase transition from a monoclinic to a cubic perovskite structure when the temperature exceeded 120°C during heating, but the cubic perovskite structure was no longer maintained at around ₁₈ ° _C during cooling. On the other hand, _{CsSn0.95Mn0.05Cl3} had a cubic perovskite structure at temperatures above -14°C, both during heating and cooling.

In addition, an AC impedance test was performed on the obtained sample of CsSn _0.95 Mn _0.05 Cl ₃ using an HS cell (manufactured by Hosen Co., Ltd.) shown in FIG. 5. As shown in FIG. 5, the HS cell 50 is a cell for battery evaluation test, in which a flanged cell container 51, a sample cell 60, a cylindrical guide 52, a flanged cell lid 53, and a pressing member 54 are stacked in order, and the flanged cell container 51 and the flanged cell lid 53 are fixed with four sets of bolts 56 and nuts 57. As shown in FIG. 6, the sample cell 60 was first prepared into a pellet 62 with a diameter of 10 mm by uniaxial pressure molding at 510 MPa, and Pt layers 61a and 61b were formed on both sides of the pellet 62. Then, an AC impedance test was performed in the temperature range of 25 to 150° C. In addition, for comparison, a sample cell was also prepared for CsSnCl ₃ in the same manner and tested. The results are shown in FIG. 7.

From the Arrhenius plots in the temperature rise and fall processes of CsSnCl ₃ and CsSn _0.95 Mn _0.05 Cl ₃ shown in FIG. 7, CsSnCl ₃ exhibited a high Cl ^-ion conductivity of the order of 10 ^-4 S / cm at around 120 ° C. in the temperature rise process, and maintained this high Cl ^-ion conductivity up to 40 ° C. in the temperature fall process, but the Cl ^-ion conductivity dropped sharply at 25 ° C. On the other hand, CsSn _0.95 Mn _0.05 Cl ₃ exhibited a high Cl ^-ion conductivity of the order of 10 ^-4 S / cm at 25 ° C. in both processes, regardless of the temperature rise and fall. From this, it became clear that CsSn _0.95 Mn _0.05 Cl ₃ has a stable cubic perovskite structure at room temperature, regardless of the temperature rise and fall, and can maintain high Cl ^-ion conductivity.

[2. All-solid-state chloride ion battery]
The sample obtained above was used as a solid electrolyte to fabricate an all-solid-state chloride ion battery, and a charge/discharge test was performed.

First, acetylene black was mixed with a sample _{of CsSn0.95Mn0.05Cl3} in a mass ratio of 5: ₁ . Then, this mixture was subjected to mechanical milling treatment at 600 rpm for 12 hours in a planetary ball mill to obtain a carbon coating material ( _{CsSn0.95Mn0.05Cl3} / _C ). Furthermore _{, BiCl3} was mixed with this in a mass ratio of 2:1. Then, this mixture was subjected to mechanical milling treatment at 150 rpm for 12 hours in a planetary ball mill to produce an _electrode composite material ( _BiCl3 / _{CsSn0.95Mn0.05Cl3} / _C ).

200 mg of _the above _{CsSn0.95Mn0.05Cl3} sample was used as _the solid electrolyte, 30 mg of the above carbon coating material was used as the protective material, 30 mg of the above electrode mixture was used as the positive electrode material, and Sn plate was used as the negative electrode material. The negative electrode Sn was charged in an excess amount relative to the mass of the electrode mixture, which is the positive electrode. Then, the protective material, the positive electrode material, the solid electrolyte, and the negative electrode material were arranged in this order, and pressed at room temperature with a pressure of 510 MPa to obtain a coin-shaped all-solid-state cell with a diameter of 10 mm in which the protective layer, the positive electrode layer, the solid electrolyte layer, and the negative electrode layer were stacked in this order.

The all-solid-state cell thus obtained was subjected to a charge-discharge test using a PEEK cell (manufactured by MTI Japan) shown in FIG. 8. As shown in FIG. 8, the PEEK cell 80 is a cell for battery evaluation test, which is prepared by stacking a negative electrode side plate 81 made of polyether ether ketone (PEEK), an all-solid-state cell 10', a cylindrical guide 82, and a positive electrode side plate 83 made of PEEK in order. As shown in FIG. 1, the all-solid-state cell 10' is a cell in which a protective layer 14, a positive electrode layer 13, a solid electrolyte layer 12, and a negative electrode layer 11 are stacked in order. Then, in a glove box, a charge-discharge test was performed under two conditions: 30° C., 0.1 mA/cm ² and 100° C., 0.1 mA/cm ^2. The results are shown in FIG. 9 and FIG. 10.

According to the charge/discharge profile shown in Fig. 9, the initial discharge capacity per weight of the positive electrode of the all-solid-state cell was 66 mAh/g. This corresponds to 26% of the theoretical capacity of 255 mAh/g for the three-electron reaction of _BiCl3 based on the following reaction formula, and demonstrated the operation of the all-solid-state chloride ion battery at room temperature.

According to the charge/discharge profile shown in Figure 9, the initial discharge capacity per weight of the positive electrode of the all-solid-state cell was 240 mAh/g. This corresponds to approximately 95% of the theoretical capacity mentioned above.

REFERENCE SIGNS LIST 10 All-solid-state chloride ion battery 11 Anode layer 12 Solid electrolyte layer 13 Cathode layer 14 Protective layer 22 First mechanical milling step 25 Second mechanical milling step 28 Third mechanical milling step 50 HS cell 60 Sample cell 80 PEEK cell

Claims (7)

An all-solid-state chloride ion battery comprising a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer,
The all-solid-state chloride ion battery, wherein the solid electrolyte layer contains a compound represented by CsSn _1-x Mn _x Cl ₃ (wherein X is a number satisfying 0<X ≦0.2 ). The all-solid-state chloride ion battery according to claim 1, wherein X in the formula is a number that satisfies 0<X≦0.1. The all-solid-state chloride ion battery according to claim 1 or 2, wherein the solid electrolyte layer has a cubic perovskite crystal at room temperature (25°C). 4. The all-solid-state chloride ion battery according to claim 1, further comprising a protective layer on the opposite side of the positive electrode layer to the solid electrolyte layer, the protective layer containing a compound represented by CsSn _1-X Mn _X Cl ₃ (wherein X is a number satisfying 0<X<1) and a conductive agent. A step of subjecting a mixture containing CsCl, SnCl ₂ and MnCl ₂ in a molar ratio of 1:1-X:X (=CsCl:SnCl ₂ :MnCl ₂ ) (X is a number satisfying 0<X≦0.2) to a mechanical milling process to obtain a solid electrolyte;
and pressing the solid electrolyte disposed between a positive electrode material and a negative electrode material to obtain an all-solid-state chloride ion battery including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer. The method for producing an all-solid-state chloride ion battery according to claim 5 further includes a step of subjecting a mixture containing a part of the solid electrolyte and a positive electrode active material containing a metal chloride to a mechanical milling process to obtain an electrode mixture as the positive electrode material. The method further includes a step of subjecting the mixture containing another part of the solid electrolyte and the conductive agent to a mechanical milling process to obtain a protective material,
7. The method for producing an all-solid-state chloride ion battery according to claim 5 or 6, wherein in the pressing step, pressing is performed while the protective material, the positive electrode material, the solid electrolyte, and the negative electrode material are arranged in this order, to obtain an all-solid-state chloride ion battery in which a protective layer, the positive electrode layer, the solid electrolyte layer, and the negative electrode layer are stacked in this order.