JP7660807B2 - 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 the charge/discharge profile of a chloride ion battery using BiCl ₃ for the positive electrode, 1M [OMIM]Cl in [BMIM]BF ₄ for the non-aqueous electrolyte, and Li for the negative electrode ([OMIM]Cl is an abbreviation for 1-methyl-3-octylimidazolium chloride, and [BMIM]BF ₄ is an abbreviation for 1-butyl-3-methylimidazolium tetrafluoroborate). It states that the theoretical capacity was 255 mAh/g and the initial capacity was about 180 mAh/g.

X. Zhao, S. Ren, M. Bruns, and M. Fichtner, “Chloride ion battery: A new member in the rechargeable battery family”, J. Power Sources, 2014, 245, pp.706-711.

However, according to the charge/discharge profile described in Non-Patent Document 1, in this non-aqueous chloride ion battery, the initial reversible capacity drops to about 50% at the third cycle. This is because the metal chlorides used in the electrode materials of chloride ion batteries have ionic bonds, and therefore are basically highly soluble in polar solvents, resulting in poor cycle characteristics.

In view of the above problems, the present invention aims to provide a chargeable and dischargeable all-solid-state chloride ion battery with improved cycle characteristics and a method for manufacturing the same.

In order to achieve the above object, one aspect of the present invention provides 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 Pb1 _- XMxCl2 _-X (wherein _M is one or more alkali metal elements selected from the group consisting of Na, K, and Rb, and 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 _PbCl2 and MCl (M is one or more alkali metal elements selected from the group consisting of Na, K, and Rb) to a mechanical milling process to obtain a solid electrolyte; and pressing the solid electrolyte between a positive electrode material and a negative electrode material, thereby obtaining 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.

As described above, according to the present invention, by employing a compound represented by Pb1 _{- XM2Cl2 -X,} which is obtained by doping _PbCl2 with MCl, as a solid electrolyte and configuring an all-solid-state chloride ion battery, it is possible to provide a chargeable and dischargeable all-solid-state chloride ion battery with improved cycle characteristics and 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 an example of a solid electrolyte used in an all-solid-state chloride ion battery according to the present invention and a reference compound. FIG. 2 is an exploded perspective view showing a schematic diagram of an HS cell used in an AC impedance test. FIG. 5 is a cross-sectional view showing a schematic diagram of a sample inserted into the HS cell of FIG. 4. 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 charge/discharge curves of the all-solid-state chloride ion battery of the example. 1 is a graph showing cycle characteristics of an all-solid-state chloride ion battery of an example and a nonaqueous chloride ion battery of a reference 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 Pb1 _{- XMxCl2 -X} (wherein M is one or more alkali metal elements selected from the group consisting of Na, K, and Rb, and 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 Pb1 _{- XMxCl2 -X} as a solid electrolyte, which is lead chloride ( _PbCl2 ) doped with an alkali metal chloride (MCl). By using _PbCl2 as a solid electrolyte, it is possible to suppress the elution of the positive electrode active material ( _BiCl3 , etc.) of the positive electrode layer 13, and by further doping it with MCl, it is possible to improve the cycle characteristics of the all-solid-state chloride ion battery 10. This is speculation, but it is believed that the doping with MCl forms vacancies in the Cl ^- sites of the crystal structure of _PbCl2 , improving the ionic conductivity of Cl- ^, and thus improving the cycle characteristics.

If the alkali metal chloride (MCl) used for doping is a chloride of sodium (Na), potassium (K), rubidium (Rb), or a combination of these chlorides, vacancies are formed in the ^Cl- site of the crystal structure of _PbCl2 as described above, and the ionic conductivity of ^Cl- can be improved. X in the above formula representing the doping amount of MCl is preferably a number that satisfies, for example, 0.01≦X≦0.1, and more preferably a number that satisfies, for example, 0.01≦X≦0.03.

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 does not exhibit ion conductivity, and may therefore contain a solid electrolyte. As the solid electrolyte used for the electrode mixture of the positive electrode layer 13, a compound represented by Pb _1-X M _X Cl _2-X (wherein M is one or more alkali metal elements selected from the group consisting of Na, K, and Rb, and X is a number satisfying 0<X<1) is preferred, as with the solid electrolyte layer 12. Other examples of the solid electrolyte that may be used include SnCl ₂ , SrCl ₂ , and BaCl ₂ .

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 the protective layer 14 prevents 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 the solid electrolyte used for the protective material, a compound represented by Pb _1-X M _X Cl 2-X (wherein M is one or more alkali metal elements selected from the group consisting of Na, K, and Rb, and X is a number satisfying 0<X<1) is preferable, as with the solid electrolyte layer 12. In addition, for example, _{SnCl 2 ,} SrCl ₂ , BaCl ₂ , etc. may be used as the solid electrolyte. In addition, as the conductive agent used for 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, the compound represented by Pb1 _{- XMxCl2 -X} is used for the solid electrolyte of the solid electrolyte layer 12. This makes it possible to suppress the elution of the positive electrode active material such as _BiCl3 of the positive electrode layer 13 into the solid electrolyte layer 12, and also to improve the ionic conductivity of the solid electrolyte layer 12, thereby improving the cycle characteristics of the all-solid-state chloride ion battery 10.

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, for example, _PbCl2 and KCl are mixed as two raw materials 21a and 21b 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 Pb _1-X M _X Cl _2-X as a solid electrolyte, the raw materials PbCl ₂ and MCl are mixed to have a desired composition. That is, they are mixed so that the molar ratio of PbCl ₂ : MCl is 1-X:X. Then, by subjecting the mixture of powders of PbCl ₂ and MCl to mechanical milling, a powder of the compound represented by Pb _1-X M _X Cl _2-X can be obtained. X is a number that satisfies 0<X<1. For example, as shown in FIG. 2, when KCl is used as MCl and X=0.02, a solid electrolyte 23 of Pb _0.98 K _0.02 Cl _1.98 can be obtained by mixing PbCl ₂ and KCl in a molar ratio of 0.98:0.02.

For example, a ball mill, a vibration mill, a turbo mill, a mechanofusion mill, a disk mill, etc. can be used for the mechanical milling process. The rotation speed and processing time of the mechanical milling process may be such that the raw material _PbCl2 and MCl powders are converted into powders of the compound represented by _{Pb1- XMxCl2 -X} , and for example, the rotation speed is 400 to 600 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 second mechanical milling step 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 step 22, but the present invention is not limited thereto, and other solid electrolytes such as _SnCl2 , _SrCl2 , and _BaCl2 may be used. Specific examples of the conductive agent 24 and the blending ratio of the solid electrolyte 23 and the conductive agent 24 are described in the above description of the positive electrode layer, and therefore will not be described 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 Pb _0.98 K _0.02 Cl _1.98 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 Pb _0.98 K _0.02 Cl _1.98 particles are carbon-coated can be obtained as the conductive coating material 26, which is represented in this specification as Pb _0.98 K _0.02 Cl _1.98 /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 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. The mechanical milling process may be performed in a dry or wet manner.

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 Pb _0.98 K _0.02 Cl _1.98 /C is used as the conductive coating material 26 and bismuth chloride (BiCl ₃ ) is used as the positive electrode active material 27, the obtained electrode mixture 29 is represented in this specification as BiCl ₃ /Pb _0.98 K _0.02 Cl _1.98 /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]
_PbCl2 and KCl were mixed in an agate mortar in three molar ratios of 0.99:0.01, 0.98:0.02, and 0.97:0.03, and each mixture was subjected to mechanical milling at 600 rpm for 12 hours 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 (Miniflex600, manufactured by Rigaku Co., Ltd.). In addition, an XRD pattern of only _PbCl2 was also obtained for comparison. The results are shown in FIG. 3.

In addition, an AC impedance test was performed on each of the obtained samples using an HS cell (manufactured by Hosen Co., Ltd.) shown in FIG. 4. As shown in FIG. 4, the HS cell 40 is a cell for battery evaluation test, in which a flanged cell container 41, a sample cell 50, a cylindrical guide 42, a flanged cell lid 43, and a pressing member 44 are stacked in order, and the flanged cell container 41 and the flanged cell lid 43 are fixed with four sets of bolts 46 and nuts 47. As shown in FIG. 5, the sample cell 50 was first prepared by uniaxially pressurizing the above sample at 510 MPa to prepare a pellet 52 with a diameter of 10 mm, and Pt layers 51a and 51b were formed on both sides of the pellet 52 by Pt sputtering. Then, an AC impedance test was performed in the temperature range of 25 to 160°C. For comparison, a sample cell was also prepared in the same manner for PbCl ₂ and tested. The results are shown in FIG. 6.

The crystal structure was identified by the XRD pattern shown in Figure 3. From the analysis results of the XRD pattern, it was found that the crystal structure of Pb1 _{- XMxCl2 -X} (X = 0.01, 0.02, 0.03) in _which PbCl2 was doped with KCl did not change before and after ball milling, regardless of the amount of KCl doped.

In addition, the Arrhenius plot shown in Figure 6 reveals that the Cl ^- ion conductivity of _PbCl2 doped with KCl is improved by 2 to 3 orders of magnitude compared to that of PbCl2 not doped with KCl. In particular, PbCl2 doped with 2 mol% _KCl showed the highest Cl ^- ion conductivity, 2.28 x ^10-4 S/cm at 160oC. This is thought to be because the doping with KCl creates vacancies at the Cl ^- sites in the crystal structure of _PbCl2 , improving the 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 (Pb _0.98 M _0.02 Cl _1.98 ) in which PbCl ₂ was doped with 2 mol% KCl 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 (Pb _0.98 M _0.02 Cl _1.98 /C). Furthermore, BiCl ₃ 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 (BiCl ₃ /Pb _0.98 M _0.02 Cl _1.98 /C).

170 mg of the sample obtained by doping 2 mol% of KCl in _the above PbCl2 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 a Pb plate was used as the negative electrode material. The negative electrode Pb was charged in an excess amount relative to the mass of the electrode mixture, which is the positive electrode. The protective material, the positive electrode material, the solid electrolyte, and the negative electrode material were then 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. 7. The PEEK cell 70 is a cell for battery evaluation test, which is prepared by stacking a negative electrode side plate 71 made of polyether ether ketone (PEEK), an all-solid-state cell 10', a cylindrical guide 72, and a positive electrode side plate 73 made of PEEK in order, as shown in FIG. 7. 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, as shown in FIG. 1. Then, a charge-discharge test was carried out in a glove box under the conditions of 160° C. and 0.1 mA/cm ^2. The results are shown in FIG. 8 and FIG. 9.

Figure 8 shows the charge/discharge profile of the all-solid-state cell. As shown in Figure 8, the initial discharge and charge capacities were 187 mAh/g and 158 mAh/g, respectively. These correspond to approximately 2.2 and 1.9 electron reactions, respectively.

FIG. 9 shows the cycle characteristics of the all-solid-state cell (Example). As shown in FIG. 9, the all-solid-state cell exhibits relatively good cycle characteristics, and it was found that the initial reversible capacity was maintained at about 85% even at the 30th cycle. For comparison, the results of a charge-discharge test of a non-aqueous cell using BiCl ₃ for the positive electrode, Li for the negative electrode, and an ionic liquid of 1M 1-methyl-3-octylimidazolium chloride in a solvent of 1-butyl-3-methylimidazolium tetrafluoroborate as an electrolyte (Non-Patent Document 1) are also shown in FIG. 9 as a reference example. As shown in FIG. 9, it has been reported that the initial reversible capacity of this non-aqueous cell decreases to about 50% at the third cycle, and it has been revealed that the cycle characteristics of the all-solid-state chloride ion battery of the present invention are significantly improved.

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 40 HS cell 50 Sample cell 70 PEEK cell

Claims (6)

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 solid electrolyte layer includes a compound represented by Pb _1-X M _X Cl _2-X (wherein M is one or more alkali metal elements selected from the group consisting of Na, K and Rb, and X is a number satisfying 0.01≦X≦0.1 ). The all-solid-state chloride ion battery according to claim 1, wherein X in the formula is a number that satisfies 0.01≦X≦0.03. 3. The all-solid-state chloride ion battery according to claim 1 or 2, 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 Pb _1-X M _X Cl _2- X (wherein M is one or more alkali metal elements selected from the group consisting of Na, K and Rb, and X is a number satisfying 0<X<1) and a conductive agent. A step of subjecting a mixture containing PbCl ₂ and MCl (M is one or more alkali metal elements selected from the group consisting of Na, K, and Rb) in a molar ratio of 1-X:X (=PbCl ₂ :MCl) (X is a number satisfying 0.01≦X≦0.1) 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 4, further comprising 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,
6. The method for producing an all-solid-state chloride ion battery according to claim 4 or 5, 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.