WO2022138148A1 - 正極活物質及びリチウムイオン二次電池 - Google Patents
正極活物質及びリチウムイオン二次電池 Download PDFInfo
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- WO2022138148A1 WO2022138148A1 PCT/JP2021/045009 JP2021045009W WO2022138148A1 WO 2022138148 A1 WO2022138148 A1 WO 2022138148A1 JP 2021045009 W JP2021045009 W JP 2021045009W WO 2022138148 A1 WO2022138148 A1 WO 2022138148A1
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- positive electrode
- active material
- electrode active
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- powder
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- 239000007774 positive electrode material Substances 0.000 title claims abstract description 105
- 229910001416 lithium ion Inorganic materials 0.000 title claims abstract description 46
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims abstract description 41
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 55
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000002131 composite material Substances 0.000 claims abstract description 43
- 239000000654 additive Substances 0.000 claims abstract description 24
- 230000000996 additive effect Effects 0.000 claims abstract description 21
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 15
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 14
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical group [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims abstract description 12
- 239000000843 powder Substances 0.000 claims description 264
- 239000007784 solid electrolyte Substances 0.000 claims description 114
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims description 86
- 239000002245 particle Substances 0.000 claims description 71
- 229910018119 Li 3 PO 4 Inorganic materials 0.000 claims description 51
- 239000000203 mixture Substances 0.000 claims description 51
- 239000011148 porous material Substances 0.000 claims description 40
- 239000007773 negative electrode material Substances 0.000 claims description 31
- 238000002441 X-ray diffraction Methods 0.000 claims description 20
- INHCSSUBVCNVSK-UHFFFAOYSA-L lithium sulfate Chemical compound [Li+].[Li+].[O-]S([O-])(=O)=O INHCSSUBVCNVSK-UHFFFAOYSA-L 0.000 abstract description 6
- 229910001386 lithium phosphate Inorganic materials 0.000 abstract description 2
- RIUWBIIVUYSTCN-UHFFFAOYSA-N trilithium borate Chemical compound [Li+].[Li+].[Li+].[O-]B([O-])[O-] RIUWBIIVUYSTCN-UHFFFAOYSA-N 0.000 abstract description 2
- TWQULNDIKKJZPH-UHFFFAOYSA-K trilithium;phosphate Chemical compound [Li+].[Li+].[Li+].[O-]P([O-])([O-])=O TWQULNDIKKJZPH-UHFFFAOYSA-K 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 description 153
- 238000002360 preparation method Methods 0.000 description 73
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- 238000001878 scanning electron micrograph Methods 0.000 description 16
- 229910052796 boron Inorganic materials 0.000 description 14
- 239000011230 binding agent Substances 0.000 description 12
- 238000000635 electron micrograph Methods 0.000 description 12
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 11
- 238000013507 mapping Methods 0.000 description 11
- 239000013078 crystal Substances 0.000 description 10
- 230000006866 deterioration Effects 0.000 description 9
- 239000010936 titanium Substances 0.000 description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
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- 229910003900 Li(Ni0.5Co0.2Mn0.3)O2 Inorganic materials 0.000 description 4
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- 238000000992 sputter etching Methods 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 3
- 229910052723 transition metal Inorganic materials 0.000 description 3
- 150000003624 transition metals Chemical class 0.000 description 3
- 229910019737 (Ni0.5Co0.2Mn0.3)(OH)2 Inorganic materials 0.000 description 2
- -1 Li 3 BO 3 Chemical compound 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 239000006230 acetylene black Substances 0.000 description 2
- 239000011149 active material Substances 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 239000012752 auxiliary agent Substances 0.000 description 2
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- 238000009616 inductively coupled plasma Methods 0.000 description 2
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- 229910008035 Li-La-Zr-O Inorganic materials 0.000 description 1
- 229910012305 LiPON Inorganic materials 0.000 description 1
- 229910006268 Li—La—Zr—O Inorganic materials 0.000 description 1
- 229910001275 Niobium-titanium Inorganic materials 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- HFCVPDYCRZVZDF-UHFFFAOYSA-N [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O Chemical compound [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O HFCVPDYCRZVZDF-UHFFFAOYSA-N 0.000 description 1
- 239000000443 aerosol Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
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- 229910002804 graphite Inorganic materials 0.000 description 1
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- 229910052738 indium Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
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- 239000007788 liquid Substances 0.000 description 1
- 150000002641 lithium Chemical class 0.000 description 1
- 229910021437 lithium-transition metal oxide Inorganic materials 0.000 description 1
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- 150000002738 metalloids Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- RJSRQTFBFAJJIL-UHFFFAOYSA-N niobium titanium Chemical compound [Ti].[Nb] RJSRQTFBFAJJIL-UHFFFAOYSA-N 0.000 description 1
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- 229910052719 titanium Inorganic materials 0.000 description 1
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Images
Classifications
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- H01M4/36—Selection of substances as active materials, active masses, active liquids
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- H01M10/05—Accumulators with non-aqueous electrolyte
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- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0561—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of inorganic materials only
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- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
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- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
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- H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
- H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
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- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
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- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Definitions
- the present invention relates to a positive electrode active material used in a lithium ion secondary battery and a lithium ion secondary battery.
- a positive electrode active material layer for a lithium ion secondary battery it is obtained by kneading and molding a powder of a lithium composite oxide (typically, a lithium transition metal oxide) and an additive such as a binder or a conductive agent.
- a powder of a lithium composite oxide typically, a lithium transition metal oxide
- an additive such as a binder or a conductive agent.
- Powder-dispersed positive electrodes are widely known. Since the powder-dispersed positive electrode contains a relatively large amount (for example, about 10% by weight) of a binder that does not contribute to the capacity, the packing density of the lithium composite oxide as the positive electrode active material is low. Therefore, there is a lot of room for improvement in the powder dispersion type positive electrode in terms of capacity and charge / discharge efficiency.
- a liquid electrolyte (electrolyte solution) using a flammable organic solvent as a diluting solvent has been conventionally used as a medium for transferring ions.
- problems such as leakage of the electrolytic solution, ignition, and explosion may occur.
- solid-state batteries are being developed in which solid electrolytes are used instead of liquid electrolytes and all other elements are made of solids. ing. Since the electrolyte of such an all-solid-state battery is solid, there is no concern about ignition, liquid leakage does not occur, and problems such as deterioration of battery performance due to corrosion are unlikely to occur.
- Patent Document 1 (WO2019 / 093222A1) contains an oriented positive electrode plate which is a lithium composite oxide sintered plate having a void ratio of 10 to 50%, Ti, and 0.4 V (against Li / Li +). )
- an all-solid lithium battery including a negative electrode plate capable of inserting and removing lithium ions and a solid electrolyte having a melting point lower than the melting point or decomposition temperature of the oriented positive electrode board or the negative electrode plate is disclosed.
- Various materials such as Li 2 SO 4 ) are disclosed.
- Such a solid electrolyte can be permeated into the voids of the electrode plate as a melt, and strong interfacial contact can be realized. As a result, it is said that the battery resistance and the rate performance at the time of charging / discharging can be remarkably improved, and the yield of battery manufacturing can be significantly improved.
- Patent Document 2 Li p (Ni x , Coy, Mn z ) O 2 (in the formula, 0.9 ⁇ p ⁇ 1.3, 0 ⁇ x ⁇ 0.8, 0 )
- An oriented positive electrode plate having a layered rock salt structure having a basic composition represented by ⁇ y ⁇ 1, 0 ⁇ z ⁇ 0.7, x + y + z 1), a Li-La-Zr-O ceramic material and / or lithium phosphate.
- an all-solid lithium battery comprising a solid electrolyte layer made of an oxynitride (LiPON) ceramic material and a negative electrode layer.
- LiPON oxynitride
- the present inventors have obtained the finding that among the above-mentioned low melting point solid electrolytes, the LiOH / Li 2 SO 4 system solid electrolytes such as 3 LiOH / Li 2 SO 4 exhibit high lithium ion conductivity.
- a cell is configured by using a LiOH / Li 2 SO 4 system solid electrolyte such as 3 LiOH / Li 2 SO 4 for a non-oriented sintered plate electrode, and battery operation is performed. Then, there is a problem that the cycle characteristic becomes low.
- the non-oriented sintered plate has an advantage that it is not easily restricted by the raw material powder in controlling the microstructure such as the pore diameter, it is convenient if the non-oriented sintered plate can be used to improve the cycle characteristics. be. Needless to say, it is needless to say that not only the sintered plate electrode but also the mixed material electrode is similarly desired to have improved cycle characteristics.
- the present inventors have made the lithium composite oxide used for the positive electrode of a lithium ion secondary battery contain at least one additive selected from Li 3 BO 3 , Li 3 PO 4 and Li 2 SO 4 . As a result, it was found that the cycle characteristics can be significantly improved.
- an object of the present invention is to provide a positive electrode active material capable of significantly improving cycle characteristics when incorporated into a lithium ion secondary battery.
- the present invention is a positive electrode active material used in a lithium ion secondary battery.
- the positive electrode active material contains a lithium composite oxide having a layered rock salt structure containing Li, Ni, Co and Mn, and at least one selected from Li 3 BO 3 , Li 3 PO 4 and Li 2 SO 4 .
- a positive electrode active material further comprising an additive is provided.
- the positive electrode layer containing the positive electrode active material and Negative electrode layer containing negative electrode active material and A LiOH / Li 2 SO 4 system solid electrolyte interposed between the positive electrode layer and the negative electrode layer, Lithium ion secondary batteries are provided, including.
- FIG. 3 is an electron micrograph and an EPMA mapping image of a cross section of a positive electrode active material (NCM) / solid electrolyte of the all-solid-state battery produced in Example 3.
- the image located on the far left is an electron micrograph (the white part corresponds to NCM and the black part corresponds to the solid electrolyte), and the EPMA mapping images of Mn, Co, and Ni are shown in order from there to the right.
- FIG. 3 is an electron micrograph and an EPMA mapping image of a cross section of a positive electrode active material (NCM) / solid electrolyte of the all-solid-state battery produced in Example 14.
- the image located on the far left is an electron micrograph (the white part corresponds to NCM and the black part corresponds to the solid electrolyte), and the EPMA mapping images of Mn, Co, and Ni are shown in order from there to the right. It is an electron micrograph (reflected electron image) of the cross section of the positive electrode plate produced in Example 8. It is an electron micrograph (reflection electron image) of the cross section of the positive electrode plate after resin embedding of the positive electrode plate produced in Example 12.
- the positive electrode active material according to the present invention is used for a lithium ion secondary battery.
- This positive electrode active material contains a lithium composite oxide having a layered rock salt structure containing Li, Ni, Co and Mn.
- the positive electrode active material then further comprises at least one additive selected from Li 3 BO 3 , Li 3 PO 4 and Li 2 SO 4 .
- the lithium composite oxide used in the lithium ion secondary battery contains at least one additive selected from Li 3 BO 3 , Li 3 PO 4 and Li 2 SO 4 to provide cycle characteristics ( In particular, the cycle maintenance rate) can be significantly improved.
- the lithium ion secondary battery provided with the negative electrode layer and the negative electrode layer has a higher cycle maintenance rate than the battery using the additive-free lithium composite oxide as the positive electrode.
- the mechanism is not clear, but it is thought to be as follows.
- the causes of deterioration of cycle characteristics are (1) a side reaction occurs at the interface between the positive electrode and the solid electrolyte during charging and discharging, and the solid electrolyte deteriorates, and (2) expansion and contraction of the lithium composite oxide due to charging and discharging. It is presumed that fine cracks are generated at the grain boundaries of the lithium composite oxide.
- Li 3 BO 3 , Li 3 PO 4 and / or Li 2 SO 4 precipitated on at least a part of the surface of the lithium composite oxide suppresses side reactions to the factor (1) above. It is presumed to do.
- Li 3 BO 3 , Li 3 PO 4 and / or Li 2 SO 4 deposited at least a part of the grain boundaries relieve the stress of expansion and contraction. Will be done. Therefore, it is preferable that the additive is present in a state of being precipitated at at least a part of the grain boundaries and the surface of the lithium composite oxide.
- the positive electrode active material contains a lithium composite oxide having a layered rock salt structure containing Li, Ni, Co and Mn.
- This lithium composite oxide is also referred to as cobalt-nickel-lithium manganate, and is abbreviated as NCM.
- the layered rock salt structure is a crystal structure in which a lithium layer and a transition metal layer other than lithium are alternately laminated with an oxygen layer sandwiched between them (typically ⁇ -NaFeO type 2 structure: cubic crystal rock salt type structure [111]. ] A structure in which transition metals and lithium are regularly arranged in the axial direction).
- the positive electrode active material according to the present invention is used for a lithium ion secondary battery, and the positive electrode is preferably in the form of a sintered plate obtained by sintering a positive electrode raw material powder. That is, the positive electrode active material is preferably in the form of a sintered plate.
- the positive electrode active material preferably has a structure in which a plurality of primary particles having a layered rock salt structure containing Li, Ni, Co and Mn are bonded. Since the sintered plate does not need to contain an electron conduction aid or a binder, the energy density of the positive electrode can be increased.
- the sintered plate may be a dense body or a porous body, and a solid electrolyte may be contained in the pores of the porous body.
- the positive electrode is a mixture of a positive electrode active material, an electron conduction aid, a lithium ion conductive material, a binder, etc., which is generally called a mixture electrode, or a positive electrode active material, a LiOH / Li 2 SO4 system solid electrolyte, and an electron conduction assist. It may be in the form of molding a mixture such as an agent (in the form of a mixture). In this case, the positive electrode active material can be in the form of powder. Thus, the positive electrode active material can be a mixed powder containing a lithium composite oxide powder and at least one powder selected from Li 3 BO 3 , Li 3 PO 4 and Li 2 SO 4 .
- the content of the additive in the positive electrode active material (that is, the content ratio of the additive to the total content of the lithium composite oxide and the additive) is a cycle characteristic regardless of the form of the positive electrode (sintered plate or mixture). From the viewpoint of improvement, it is preferably 0.1 to 10% by weight, more preferably 0.5 to 7.0% by weight, and even more preferably 1.0 to 6.0% by weight. It is considered that the above-mentioned content of the additive is almost the same between the amount of the additive charged at the time of producing the positive electrode active material and the content of the additive in the finally obtained positive electrode active material. This can be inferred from the fact that, for example, there is almost no change in weight when the additive alone is measured by thermogravimetric analysis (TG).
- TG thermogravimetric analysis
- the sintered plate is on the (003) plane with respect to the diffraction intensity I [104] due to the (104) plane in the XRD profile measured by X-ray diffraction (XRD).
- the degree of orientation I [003] / I [104] which is defined as the ratio of the resulting diffraction intensity I [003] , is 1.2 to 3.6, preferably 1.2 to 3.5. It is more preferably 1.2 to 3.0, and even more preferably 1.2 to 2.6.
- a plane other than the crystal plane ((003) plane) where lithium ions are satisfactorily transferred in and out for example, a plane (101) or a plane (104). ) Side) and the other side (003) side.
- each diffraction intensity of the (003) plane and the (104) plane by XRD is conveniently used as an index for calculating the degree of orientation.
- the non-oriented sintered body has an advantage that it is not easily restricted by the raw material powder in controlling the microstructure such as the pore diameter. Therefore, the microstructure of the sintered body (for example, the pore diameter) is controlled. It becomes easier to select a raw material powder that is convenient for the sinter, and it becomes easier to realize improvement of cycle characteristics.
- the porosity of the sintered plate is preferably 20 to 40%, more preferably 20 to 38%, still more preferably 20 to 36%, and particularly preferably 20 to 36%. It is 20 to 33%. Within such a range, when the battery is manufactured, the pores can be sufficiently filled with the solid electrolyte, and the proportion of the positive electrode active material in the positive electrode increases, so that the high energy density of the battery can be achieved. It can be realized.
- the "porosity” is the volume ratio of pores in the sintered plate. This porosity can be measured by image analysis of a cross-sectional SEM image of the sintered plate. For example, after the sintered plate is embedded with resin and the cross section is polished by ion milling, the polished cross section is observed with an SEM (scanning electron microscope) to obtain a cross section SEM image (for example, a magnification of 500 to 1000 times), and the obtained SEM is obtained. By analyzing the image, the ratio (%) of the area filled with the resin to the total area of the part of the electrode active material and the part filled with the resin (the part that was originally a pore) is calculated and fired. The pore ratio (%) of the knot may be calculated.
- the porosity may be measured without embedding the sintered plate with resin.
- the porosity of a sintered plate (positive electrode plate taken out from an all-solid secondary battery) in which the pores are filled with the solid electrolyte can be measured with the solid electrolyte still filled.
- the average pore diameter of the sintered plate is preferably 3.5 ⁇ m or more, more preferably 3.5 to 15.0 ⁇ m, still more preferably 3.5 to. It is 10.0 ⁇ m, particularly preferably 3.5 to 8.0 ⁇ m. Within such a range, the number of solid electrolyte portions (solid electrolyte portions located at a distance from the interface) that are less susceptible to deterioration due to side reactions between the solid electrolyte and the lithium composite oxide increases.
- the "average pore diameter” is an average value of the diameters of pores contained in the sintered plate of the electrode. Such “diameter” is typically the length of a line segment (Martin diameter) that divides the projected area of the pore into two equal parts. In the present invention, the “mean value” is preferably calculated on the basis of the number of pieces.
- This average pore diameter can be measured by image analysis of a cross-sectional SEM image of the sintered plate. For example, the SEM image obtained by the above-mentioned porosity measurement is analyzed, and the portion of the sintered plate that is filled with the electrode active material and the portion filled with the resin (the portion that was originally the pores) is separated and then filled with the resin.
- the maximum Martin diameter of each region may be obtained in the region of the portion, and the average value thereof may be used as the average pore diameter of the sintered plate. If the measurement can be performed with a desired accuracy, the average pore diameter may be measured without embedding the sintered plate with resin. For example, the average pore diameter of a sintered plate (positive electrode plate taken out from an all-solid-state secondary battery) in which the pores are filled with the solid electrolyte can be measured with the solid electrolyte still filled.
- the interface length per unit cross-sectional area of 1 ⁇ m 2 of the sintered plate is preferably 0.45 ⁇ m or less, more preferably 0.10 to 0.40 ⁇ m, and further. It is preferably 0.10 to 0.35 ⁇ m, and particularly preferably 0.10 to 0.30 ⁇ m. Within such a range, the chances of a side reaction between the lithium composite oxide and the solid electrolyte are reduced. Therefore, it is considered that the element diffusion between the solid electrolyte and the lithium composite oxide is suppressed, the decrease in Li ion conductivity due to the deterioration of the solid electrolyte is alleviated, and the discharge capacity and the cycle characteristics are more effectively improved.
- the "interface length per 1 ⁇ m 2 unit cross-sectional area" is the total length of the interface of all pores / active materials contained in the unit cross-sectional area per 1 ⁇ m 2 unit cross-sectional area of the sintered plate. be.
- This interface length can be measured by image analysis of a cross-sectional SEM image of the sintered plate. For example, the SEM image obtained by the above-mentioned porosity measurement is analyzed to separate the electrode active material portion and the resin-filled portion (the originally pore-filled portion) of the sintered plate, and then filled with the resin.
- the peripheral length of the entire region that is, the total length of the interface between the portion of the positive electrode active material and the portion filled with the resin
- the entire region analyzed that is, the portion of the positive electrode active material and the resin.
- the perimeter may be divided by the area of the entire analyzed region to obtain the interface length per unit cross-sectional area of 1 ⁇ m 2 . If the measurement can be performed with a desired accuracy, the interface length may be measured without embedding the sintered plate with resin. For example, the interface length of a sintered plate (positive electrode plate taken out from an all-solid-state secondary battery) in which the pores are filled with a solid electrolyte can be measured with the solid electrolyte still filled.
- the thickness of the positive electrode is preferably 30 to 300 ⁇ m, more preferably 50 to 300 ⁇ m, still more preferably 80 to 300 ⁇ m from the viewpoint of improving the energy density of the battery, regardless of the form of the positive electrode (sintered plate or mixture). Is.
- the lithium composite oxide sintered plate according to the preferred embodiment of the present invention may be produced by any method, but preferably (a) preparation of NCM raw material powder. It is manufactured through (b) preparation of an NCM green sheet and (c) firing of the NCM green sheet.
- NCM raw material powder is prepared.
- the preferred NCM raw material powder is Li (Ni 0.5 Co 0.2 Mn 0.3 ) O 2 powder or Li (Ni 0.3 Co 0.6 Mn 0.1 ) O 2 powder.
- the Li (Ni 0.5 Co 0.2 Mn 0.3 ) O 2 powder was weighed so that the molar ratio of Li / (Ni + Co + Mn) was 1.00 to 1.30 (Ni 0.5 Co 0 ). .2 Mn 0.3 ) (OH) 2 powder and Li 2 CO 3 powder are mixed and then fired at 700 to 1200 ° C. (preferably 750 to 1000 ° C.) for 1 to 24 hours (preferably 2 to 15 hours). Can be produced by.
- Li (Ni 0.3 Co 0.6 Mn 0.1 ) O 2 powder was weighed so that the molar ratio of Li / (Ni + Co + Mn) was 1.00 to 1.30 (Ni 0.3 ).
- Co 0.6 Mn 0.1 ) (OH) 2 powder and Li 2 CO 3 powder are mixed and then baked at 700 to 1200 ° C (preferably 750 to 1000 ° C) for 1 to 24 hours (preferably 2 to 15 hours). By doing so, it can be preferably produced.
- a large NCM raw material powder having a volume-based D50 particle size of 3 to 20 ⁇ m (preferably 5 to 15 ⁇ m) is used. It is preferable to prepare a small NCM raw material powder having a volume-based D50 particle size of 0.05 to 1 ⁇ m (preferably 0.1 to 0.6 ⁇ m) and use a mixed powder obtained by mixing these.
- the ratio of the large NCM raw material powder to the mixed powders of these two types, large and small, is preferably 50 to 99% by weight, more preferably 70 to 95% by weight.
- the smaller NCM raw material powder may be produced by pulverizing the larger NCM raw material powder by a known method such as a ball mill.
- Additives such as Li 3 BO 3 , Li 3 PO 4 , and Li 2 SO 4 may be added to the calcined NCM raw material powder prepared as described above, or (Ni 0.5 Co 0.2 Mn). It may be added to NCM precursor powder before firing such as 0.3 ) (OH) 2 powder or (Ni 0.3 Co 0.6 Mn 0.1 ) (OH) 2 . Further, when obtaining a mixed powder of two types, large and small, as described above, an additive may be added to at least one of a large NCM raw material powder and a small NCM raw material powder.
- NCM Green Sheet NCM raw material powder (preferably the above-mentioned NCM mixed powder), solvent, binder, plasticizer, and dispersant are mixed to form a paste. After adjusting the viscosity of the obtained paste, an NCM green sheet is produced by molding into a sheet.
- NCM sintered plate Preparation of NCM Sintered Plate
- the NCM green sheet thus produced is cut into a desired size and shape, placed in a firing sheath, and fired.
- the firing rate is 50 to 600 ° C./h (preferably 100 to 300 ° C./h), and the temperature is raised to 800 to 1000 ° C. (preferably 850 to 970 ° C.) for 1 to 24 hours (preferably 2 to 2 to 970 ° C.). It is desirable to do this by holding for 12 hours).
- NCM sintered plate a lithium composite oxide sintered plate
- the positive electrode active material according to the present invention is used for a lithium ion secondary battery (typically an all-solid-state battery). Therefore, according to a preferred embodiment of the present invention, there is provided a lithium ion secondary battery including a positive electrode layer containing the positive electrode active material of the present invention, a negative electrode layer, and a LiOH / Li 2SO4 system solid electrolyte.
- the negative electrode layer contains a negative electrode active material.
- the LiOH / Li 2 SO 4 system solid electrolyte is interposed between the positive electrode layer and the negative electrode layer.
- the lithium ion secondary battery using the lithium composite oxide to which Li 3 BO 3 , Li 3 PO 4 and / or Li 2 SO 4 is added for the positive electrode layer is a conventional lithium ion without additives. It can exhibit a higher cycle maintenance rate than a lithium ion secondary battery using a composite oxide as a positive electrode layer.
- the positive electrode layer is preferably in the form of a sintered plate obtained by sintering the positive electrode raw material powder. That is, the positive electrode active material is preferably in the form of a sintered plate. Since the sintered plate does not need to contain an electron conduction aid or a binder, the energy density of the positive electrode layer can be increased.
- the sintered plate may be a dense body or a porous body, and a solid electrolyte may be contained in the pores of the porous body.
- the positive electrode layer is a mixture of a positive electrode active material, an electron conduction aid, a lithium ion conductive material, a binder, etc., which is generally called a mixture electrode, or a positive electrode active material, a LiOH / Li 2 SO4 system solid electrolyte, and electron conduction. It may be in the form of molding a mixture such as an auxiliary agent (in the form of a mixture). That is, the positive electrode layer may contain particles of the positive electrode active material, particles of the LiOH / Li 2SO4 system solid electrolyte, and an electron conduction aid in the form of a mixture.
- the density (filling rate) of the positive electrode active material in the positive electrode in the mixed material form is preferably 50 to 80% by volume, more preferably 55 to 80% by volume, still more preferably 60 to 80% by volume, particularly in the form of the positive electrode. It is preferably 65 to 75% by volume. If the density is within such a range, the voids in the positive electrode active material can be sufficiently filled with the solid electrolyte, and the proportion of the positive electrode active material in the positive electrode increases, so that the energy density as a battery is high. Can be realized.
- the value of the density (filling rate) in this mixture form corresponds to a value obtained by subtracting the ratio of the portion (including the pores) other than the positive electrode active material from 100.
- the negative electrode layer (typically the negative electrode plate) contains the negative electrode active material.
- a negative electrode active material generally used for a lithium ion secondary battery can be used.
- Examples of such general negative electrode active materials include carbon-based materials, metals or metalloids such as Li, In, Al, Sn, Sb, Bi, Si, or alloys containing any of these. ..
- an oxide-based negative electrode active material may be used.
- a particularly preferable negative electrode active material contains a material capable of inserting and removing lithium ions at 0.4 V (vs. Li / Li + ) or higher, and preferably contains Ti.
- the negative electrode active material satisfying such conditions is preferably an oxide containing at least Ti.
- Preferred examples of such a negative electrode active material include lithium titanate Li 4 Ti 5 O 12 (hereinafter, may be referred to as LTO), niobium titanium composite oxide Nb 2 TiO 7 , and titanium oxide TiO 2 .
- LTO and Nb 2 TiO 7 are preferable, and LTO is more preferable.
- LTO is typically known to have a spinel-type structure, other structures may be adopted during charging / discharging. For example, LTO reacts in a two-phase coexistence of Li 4 Ti 5 O 12 (spinel structure) and Li 7 Ti 5 O 12 (rock salt structure) during charging and discharging. Therefore, LTO is not limited to the spinel structure.
- the negative electrode is a mixture of a negative electrode active material, an electron conduction aid, a lithium ion conductive material, a binder, etc., which is generally called a mixture electrode, or a negative electrode active material, a LiOH / Li 2SO4 solid electrolyte, an electron conduction aid, etc. It may be in the form of a molded mixture of. That is, the negative electrode may contain particles of the negative electrode active material, particles of the LiOH / Li 2SO4 system solid electrolyte, and an electron conduction aid in the form of a mixture. However, the negative electrode is preferably in the form of a sintered plate obtained by sintering the negative electrode raw material powder.
- the negative electrode or the negative electrode active material is preferably in the form of a sintered plate. Since the sintered plate does not need to contain an electron conduction aid or a binder, the energy density of the negative electrode can be increased.
- the sintered plate may be a dense body or a porous body, and a solid electrolyte may be contained in the pores of the porous body.
- the negative electrode active material particles have a preferable particle size of 0.05 to 50 ⁇ m, more preferably 0.1 to 30 ⁇ m, and even more preferably 0.5 to 20 ⁇ m.
- the LiOH / Li 2 SO4 system solid electrolyte particles have a preferable particle size of 0.01 to 50 ⁇ m, more preferably 0.05 to 30 ⁇ m, and further preferably 0.1 to 20 ⁇ m.
- the electron conduction aid is not particularly limited as long as it is an electron conduction substance generally used for an electrode, but a carbon material is preferable.
- Preferred examples of carbon materials include, but are not limited to, carbon black, graphite, carbon nanotubes, graphene, graphene reduced oxide, and any combination thereof, but various other carbon materials can also be used. ..
- the density (filling rate) of the negative electrode active material in the negative electrode is preferably 55 to 80% by volume, more preferably 60 to 80%, still more preferably 65 to 65, regardless of the form of the negative electrode (sintered plate or mixture). It is 75%. If the density is within such a range, the voids in the negative electrode active material can be sufficiently filled with the solid electrolyte, and the proportion of the negative electrode active material in the negative electrode increases, so that the energy density as a battery is high. Can be realized.
- the value of the density (filling rate) in the mixed material form corresponds to a value obtained by subtracting the ratio of the portion (including the pores) other than the negative electrode active material from 100.
- the thickness of the negative electrode is preferably 40 to 410 ⁇ m, more preferably 65 to 410 ⁇ m, still more preferably 100 to 410 ⁇ m, regardless of the form of the negative electrode (sintered plate or mixture) from the viewpoint of improving the energy density of the battery. Particularly preferably, it is 107 to 270 ⁇ m.
- the solid electrolyte is a LiOH / Li 2 SO 4 system solid electrolyte.
- the LiOH / Li 2 SO 4 system solid electrolyte contains a solid electrolyte identified as 3 LiOH / Li 2 SO 4 by X-ray diffraction.
- This preferred solid electrolyte contains 3LiOH ⁇ Li 2 SO 4 as the main phase. Whether or not 3LiOH / Li 2 SO 4 is contained in the solid electrolyte can be confirmed by identifying the X-ray diffraction pattern using 032-0598 of the ICDD database.
- 3LiOH / Li 2 SO 4 refers to a crystal structure that can be regarded as the same as 3LiOH / Li 2 SO 4 , and the crystal composition does not necessarily have to be the same as 3LiOH / Li 2 SO 4 .
- the solid electrolyte contains a dopant such as boron (for example, 3LiOH / Li 2 SO 4 in which boron is dissolved and the X-ray diffraction peak is shifted to the high angle side), the crystal structure is 3LiOH / Li 2 SO. As long as it can be regarded as the same as 4 , it is referred to herein as 3LiOH ⁇ Li 2 SO 4 .
- the solid electrolyte used in the present invention also allows the inclusion of unavoidable impurities.
- the LiOH / Li 2 SO 4 system solid electrolyte may contain a different phase in addition to the main phase of 3LiOH / Li 2 SO 4 .
- the heterogeneous phase may contain a plurality of elements selected from Li, O, H, S and B, or may consist only of a plurality of elements selected from Li, O, H, S and B. May be.
- Examples of the heterogeneous phase include LiOH, Li 2 SO 4 and / or Li 3 BO 3 derived from the raw material. Regarding these heterogeneous phases, it is considered that unreacted raw materials remained when forming 3LiOH / Li2SO4 , but since they do not contribute to lithium ion conduction , the amount is smaller except for Li3BO3 . desirable.
- a heterogeneous phase containing boron such as Li 3 BO 3
- the solid electrolyte may be composed of a single phase of 3LiOH / Li 2 SO 4 in which boron is dissolved.
- the LiOH / Li 2 SO 4 system solid electrolyte (particularly 3 LiOH / Li 2 SO 4 ) preferably further contains boron.
- boron By further containing boron in the solid electrolyte identified as 3LiOH / Li 2SO 4 , it is possible to significantly suppress the decrease in lithium ion conductivity even after holding at a high temperature for a long time. Boron is presumed to be incorporated into one of the sites of the crystal structure of 3LiOH / Li2SO4 and improve the stability of the crystal structure with respect to temperature.
- the molar ratio (B / S) of boron B to sulfur S contained in the solid electrolyte is preferably more than 0.002 and less than 1.0, more preferably 0.003 or more and 0.9 or less, still more preferably. It is 0.005 or more and 0.8 or less.
- B / S is within the above range, it is possible to improve the maintenance rate of lithium ion conductivity. Further, when the B / S is within the above range, the content of the unreacted heterogeneous phase containing boron is low, so that the absolute value of the lithium ion conductivity can be increased.
- the LiOH / Li 2 SO 4 system solid electrolyte may be a green compact of a powder obtained by crushing a melt-solidified body, but a melt-solidified body (that is, one solidified after being heated and melted) is preferable.
- the method for crushing the melt-solidified body is not particularly limited, but a method using a general mortar, ball mill, jet mill, roller mill, cutter mill, ring mill or the like can be adopted, and a wet method or a dry method may be adopted.
- the LiOH / Li 2 SO4 solid electrolyte is also filled in the pores of the positive electrode layer and / or the pores of the negative electrode layer, or is incorporated into the positive electrode layer and / or the negative electrode layer (as a component of the mixture).
- the thickness of the solid electrolyte layer (excluding the portion that has entered the pores in the positive electrode layer and the negative electrode layer) is preferably 1 to 500 ⁇ m, more preferably 3 to 50 ⁇ m, from the viewpoint of charge / discharge rate characteristics and the insulating property of the solid electrolyte. More preferably, it is 5 to 40 ⁇ m.
- a positive electrode with a current collector formed if necessary
- a positive electrode with a current collector formed if necessary
- a positive electrode with a current collector formed if necessary
- This can be done by preparing the negative electrode and ii) sandwiching a solid electrolyte between the positive electrode and the negative electrode and applying pressure, heating, or the like to integrate the positive electrode, the solid electrolyte, and the negative electrode.
- the positive electrode, the solid electrolyte, and the negative electrode may be bonded by other methods.
- a method of placing a solid electrolyte molded body or powder on one of the electrodes a method of screen-printing a paste of the solid electrolyte powder on the electrode.
- Examples thereof include a method of colliding and solidifying a solid electrolyte powder by an aerosol disposition method or the like using an electrode as a substrate, and a method of depositing a solid electrolyte powder on an electrode by an electrophoresis method to form a film.
- the production of an all-solid secondary battery when a mixture electrode is used is, for example, a positive electrode mixture powder (including positive electrode active material particles, a solid electrolyte particle, and an electron conduction auxiliary agent), a solid electrolyte powder, and a negative electrode combination.
- a positive electrode mixture powder including positive electrode active material particles, a solid electrolyte particle, and an electron conduction auxiliary agent
- a solid electrolyte powder and a negative electrode combination.
- the material powder including negative electrode active material particles, solid electrolyte particles, and electron conduction aid
- the charging and pressurization of the various powders may be performed in any order so that the positive electrode layer, the solid electrolyte layer, and the negative electrode layer are finally in that order.
- the positive electrode active material particles are in the form of a mixed powder containing a lithium composite oxide powder and at least one powder selected from Li 3 BO 3 , Li 3 PO 4 and Li 2 SO 4 . Can be.
- Example 1 to 18 The example described below is an example relating to an all-solid-state secondary battery in which the positive electrode and the negative electrode are in the form of a sintered plate.
- NCM raw material powders 1 to 22 for producing a positive electrode plate were produced.
- Tables 1A to 1C show a summary of the characteristics of these raw material powders.
- NCM raw material powder 1 Preparation of NCM raw material powder 1
- Commercially available (Ni 0.5 Co 0.2 Mn 0.3 ) (OH) 2 powder (average particle size 9 to 10 ⁇ m) and Li weighed so that the molar ratio of Li / (Ni + Co + Mn) is 1.15.
- 2 CO 3 powder (average particle size 3 ⁇ m) was mixed and then held at 750 ° C. for 10 hours to obtain NCM raw material powder 1.
- the volume-based D50 particle size of this powder was 8 ⁇ m.
- NCM raw material powder 2 [Preparation of NCM raw material powder 2] Add 2.45% by weight of Li 3 BO 3 (relative to the total amount of NCM raw material powder 1 and Li 3 BO 3 ) to the NCM raw material powder 1 and wet pulverize the ball mill to make the volume-based D50 particle size about 0.4 ⁇ m. After adjusting to the above, the mixture was dried to obtain NCM raw material powder 2.
- NCM raw material powder 3 Preparation of NCM raw material powder 3
- NCM raw material powder 4 The volume-based D50 particle size of the NCM raw material powder 1 was adjusted to about 5.5 ⁇ m by wet pulverization with a ball mill, and then dried to obtain the NCM raw material powder 4.
- NCM raw material powder 5 Add 1.0% by weight of Li 3 PO 4 to the NCM raw material powder 1 (relative to the total amount of the NCM raw material powder 1 and Li 3 PO 4 ), and wet pulverize the ball mill to obtain a volume-based D50 particle size of about 5.5 ⁇ m. Then, it was dried to obtain NCM raw material powder 5.
- NCM raw material powder 6 To the NCM raw material powder 1, 5.0% by weight of Li 3 PO 4 (relative to the total amount of the NCM raw material powder 1 and Li 3 PO 4 ) was added, and the volume standard D50 particle size was about 5.5 ⁇ m by wet grinding with a ball mill. Then, it was dried to obtain NCM raw material powder 6.
- NCM raw material powder 7 Preparation of NCM raw material powder 7
- 2 CO 3 powder average particle size 3 ⁇ m was mixed and then held at 850 ° C. for 10 hours to obtain NCM raw material powder 7.
- the volume-based D50 particle size of this powder was 6.5 ⁇ m.
- NCM raw material powder 8 Add 9.2% by weight of Li 3 BO 3 (relative to the total amount of NCM raw material powder 7 and Li 3 BO 3 ) to the NCM raw material powder 7 and wet pulverize the ball mill to make the volume-based D50 particle size about 0.4 ⁇ m. After adjusting to the above, the mixture was dried to obtain NCM raw material powder 8.
- NCM raw material powder 9 [Preparation of NCM raw material powder 9] Add 16.8% by weight of Li 3 BO 3 (relative to the total amount of NCM raw material powder 7 and Li 3 BO 3 ) to the NCM raw material powder 7 and wet pulverize the ball mill to make the volume-based D50 particle size about 0.4 ⁇ m. After adjusting to the above, the mixture was dried to obtain NCM raw material powder 9.
- NCM raw material powder 10 Preparation of NCM raw material powder 10
- NCM raw material powder 11 [Preparation of NCM raw material powder 11] Add 16.8% by weight of Li 2 SO 4 to the NCM raw material powder 7 (relative to the total amount of the NCM raw material powder 7 and Li 2 SO 4 ), and wet pulverize the ball mill to obtain a volume-based D50 particle size of about 0.4 ⁇ m. Then, it was dried to obtain NCM raw material powder 11.
- NCM raw material powder 12 Preparation of NCM raw material powder 12
- the volume-based D50 particle size of the NCM raw material powder 7 was adjusted to about 0.4 ⁇ m by wet pulverization with a ball mill, and then dried to obtain the NCM raw material powder 13.
- the volume-based D50 particle size of the NCM raw material powder 7 was adjusted to about 4.3 ⁇ m by wet pulverization with a ball mill, and then dried to obtain the NCM raw material powder 14.
- NCM raw material powder 15 Preparation of NCM raw material powder 15
- 2 CO 3 powder average particle size 3 ⁇ m
- NCM raw material powder 15 was obtained.
- NCM raw material powder 16 Preparation of NCM raw material powder 16
- 2 CO 3 powder average particle size 3 ⁇ m
- Li 3 PO 4 powder average particle size 0.5 ⁇ m
- the mixture was kept at 870 ° C. for 10 hours to obtain NCM raw material powder 16.
- the volume-based D50 particle size of this powder was 7.4 ⁇ m.
- NCM raw material powder 17 Preparation of NCM raw material powder 17
- the mixture was kept at 870 ° C. for 10 hours to obtain NCM raw material powder 17.
- the volume-based D50 particle size of this powder was 7.5 ⁇ m.
- NCM raw material powder 18 Preparation of NCM raw material powder 18
- the mixture was kept at 870 ° C. for 10 hours to obtain an NCM raw material powder 18.
- the volume-based D50 particle size of this powder was 7.7 ⁇ m.
- NCM raw material powder 19 Preparation of NCM raw material powder 19
- 2 CO 3 powder average particle size 3 ⁇ m was mixed and then held at 750 ° C. for 10 hours to obtain NCM raw material powder 19.
- the volume-based D50 particle size of this powder was 7.0 ⁇ m.
- NCM raw material powder 19 NCM raw material powder 19 with Li 3 BO 3 (relative to the total amount of NCM raw material powder 19 and Li 3 BO 3 ) 9.2% by weight, Li 3 PO 4 (total of NCM raw material powder 19 and Li 3 PO 4 ). After adding 1.0% by weight based on the amount and adjusting the volume-based D50 particle size to about 0.5 ⁇ m by wet pulverization of a ball mill, the powder was dried to obtain NCM raw material powder 20.
- NCM raw material powder 21 NCM raw material powder 19 with Li 3 BO 3 (relative to the total amount of NCM raw material powder 19 and Li 3 BO 3 ) 9.2% by weight, Li 3 PO 4 (total of NCM raw material powder 19 and Li 3 PO 4 ). After adding 2.5% by weight based on the amount and adjusting the volume-based D50 particle size to about 0.5 ⁇ m by wet pulverization of a ball mill, the powder was dried to obtain NCM raw material powder 21.
- NCM raw material powder 19 with Li 3 BO 3 (relative to the total amount of NCM raw material powder 19 and Li 3 BO 3 ) 9.2% by weight, Li 3 PO 4 (total of NCM raw material powder 19 and Li 3 PO 4 ). (With respect to the amount) 5.0% by weight was added, and the volume-based D50 particle size was adjusted to about 0.5 ⁇ m by wet pulverization of a ball mill, and then dried to obtain NCM raw material powder 22.
- Example 1 Preparation of positive electrode plate (1a) Preparation of NCM green sheet First, as shown in Tables 1A to 1C, NCM raw material powders 1 and 2 are uniformly mixed at a mixing ratio (weight ratio) of 80:20 to NCM. A mixed powder A was prepared. This mixed powder A was mixed with a solvent for tape molding, a binder, a plasticizer, and a dispersant. After adjusting the viscosity of the obtained paste, an NCM green sheet was produced by molding it into a sheet on a PET (polyethylene terephthalate) film. The thickness of the NCM green sheet was adjusted so that the thickness after firing was 100 ⁇ m.
- NCM Sintered Plate The NCM green sheet peeled off from the PET film was punched out into a circle with a diameter of 11 mm and placed in a firing sheath. Baking was performed by raising the temperature to 940 ° C. at a heating rate of 200 ° C./h and holding it for 10 hours. The thickness of the obtained sintered plate was about 100 ⁇ m according to SEM observation. An Au film (thickness 100 nm) was formed as a current collector layer on one side of this NCM sintered plate by sputtering. In this way, a positive electrode plate was obtained.
- the thickness and porosity (% by volume) of each of the LTO sintered plates in the state were measured as follows. First, the positive electrode plate (or the negative electrode plate) was embedded with resin, and then the cross section was polished by ion milling, and then the polished cross section was observed by SEM to obtain a cross section SEM image. The thickness was calculated from this SEM image.
- the SEM images for porosity measurement were images with a magnification of 1000 times and a magnification of 500 times.
- the obtained image is binarized using image analysis software (Image-Pro Premier manufactured by Media Cybernetics), and the positive electrode active material (or negative electrode active material) in the positive electrode plate (or negative electrode plate) is subjected to binarization treatment.
- Porosity of the positive electrode plate (or negative electrode plate) by calculating the ratio (%) of the area filled with resin to the total area of the part filled with resin and the part filled with resin (the part that was originally pores). It was set to (%).
- the threshold value for binarization was set using Otsu's binarization as a discriminant analysis method.
- the porosity of the positive electrode plate is as shown in Table 2, and the porosity of the negative electrode plate was 38% (that is, the density was 62%).
- the average pore diameter was measured as follows. Image analysis software (Image-Pro Premier manufactured by Media Cybernetics) is used to perform a binarization process, and the positive electrode plate (or negative electrode plate) is filled with a portion of the positive electrode active material (or negative electrode active material) and a resin. The part (the part that was originally a pore) was cut out. Then, in the region of the portion filled with the resin, the maximum Martin diameter of each region was obtained, and the average value thereof was taken as the average pore diameter ( ⁇ m) of the positive electrode plate (or the negative electrode plate).
- the average pore diameter of the positive electrode plate is as shown in Table 2, and the average pore diameter of the negative electrode plate was 2.1 ⁇ m.
- the inductively coupled plasma is the molar ratio Li / (Ni + Co + Mn) of the Li content to the total content of Ni, Co and Mn in the positive electrode plate produced in (1) above. It was calculated from the measurement result of the metal element analysis by the emission spectroscopic analysis method (ICP-AES method). The results are shown in Table 2.
- Example 2 In the preparation of the positive electrode plate of (1) above, NCM mixed powder B containing NCM raw material powders 1 and 3 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 90:10 instead of 1) mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 950 ° C., and various evaluations were performed.
- Example 3 In the preparation of the positive electrode plate of (1) above, except that 1) only the NCM raw material powder 5 shown in Tables 1A to 1C was used instead of the mixed powder A, and 2) the firing temperature was set to 920 ° C. , A positive electrode plate and a battery were produced in the same manner as in Example 1, and various evaluations were performed. In addition, the battery produced in this example was disassembled in a glove box, and the interface between the positive electrode plate and the solid electrolyte was observed with an electron microscope and elemental mapping was performed with an electron probe microanalyzer (EPMA).
- EPMA electron probe microanalyzer
- FIG. 1 shows an electron micrograph and an EPMA mapping image of a cross section of a positive electrode active material (NCM) / solid electrolyte of the all-solid-state battery produced in this example.
- NCM positive electrode active material
- the leftmost image in FIG. 1 is an electron micrograph (white part corresponds to NCM, black part corresponds to solid electrolyte), and EPMA mapping images of Mn, Co, and Ni are shown in order from there to the right. ..
- Example 4 In the preparation of the positive electrode plate of (1) above, except that 1) only the NCM raw material powder 6 shown in Tables 1A to 1C was used instead of the mixed powder A, and 2) the firing temperature was set to 920 ° C. , A positive electrode plate and a battery were produced in the same manner as in Example 1, and various evaluations were performed.
- Example 5 In the preparation of the positive electrode plate of (1) above, NCM mixed powder C containing NCM raw material powders 7 and 8 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 90:10 instead of 1) mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed.
- Example 6 In the preparation of the positive electrode plate of (1) above, NCM mixed powder D containing NCM raw material powders 7 and 8 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 95: 5 instead of 1) mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 950 ° C., and various evaluations were performed.
- Example 7 In the preparation of the positive electrode plate of (1) above, NCM mixed powder E containing NCM raw material powders 7 and 9 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 95: 5 instead of 1) mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed.
- Example 8 In the preparation of the positive electrode plate of (1) above, NCM mixed powder F containing NCM raw material powders 7 and 10 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 95: 5 instead of 1) mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed. Further, FIG. 3 shows an electron micrograph (reflected electron image) of the cross section of the positive electrode plate produced in this example.
- Example 9 In the preparation of the positive electrode plate of (1) above, NCM mixed powder G containing NCM raw material powders 7 and 11 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 95: 5 instead of 1) mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed.
- Example 10 In the preparation of the positive electrode plate of (1) above, the NCM mixed powder H containing the NCM raw material powders 7 and 12 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 95: 5 instead of 1) the mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed.
- Example 11 In the preparation of the positive electrode plate of (1) above, the NCM mixed powder I containing the NCM raw material powders 16 and 20 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 90:10 instead of 1) the mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed.
- Example 12 In the preparation of the positive electrode plate of (1) above, the NCM mixed powder J containing the NCM raw material powders 17 and 21 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 90:10 instead of 1) the mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed.
- FIG. 4 shows an electron micrograph (reflected electron image) of a cross section of the positive electrode plate after resin embedding of the positive electrode plate produced in this example.
- Example 13 In the preparation of the positive electrode plate of (1) above, the NCM mixed powder K containing the NCM raw material powders 18 and 22 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 90:10 instead of 1) the mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 920 ° C., and various evaluations were performed.
- Example 14 (comparison) In the preparation of the positive electrode plate of (1) above, except that 1) only the NCM raw material powder 4 shown in Tables 1A to 1C was used instead of the mixed powder A, and 2) the firing temperature was set to 920 ° C. , A positive electrode plate and a battery were produced in the same manner as in Example 1, and various evaluations were performed. In addition, the battery produced in this example was disassembled in a glove box, and the interface between the positive electrode plate and the solid electrolyte was observed by an electron microscope and elemental mapping was performed by an electron probe microanalyzer (EPMA).
- EPMA electron probe microanalyzer
- FIG. 2 shows an electron micrograph and an EPMA mapping image of a cross section of a positive electrode active material (NCM) / solid electrolyte of the all-solid-state battery produced in this example.
- NCM positive electrode active material
- the leftmost image in FIG. 2 is an electron micrograph (white part corresponds to NCM, black part corresponds to solid electrolyte), and EPMA mapping images of Mn, Co, and Ni are shown in order from there to the right. ..
- Example 15 (comparison) In the preparation of the positive electrode plate of (1) above, except that 1) only the NCM raw material powder 14 shown in Tables 1A to 1C was used instead of the mixed powder A, and 2) the firing temperature was set to 920 ° C. , A positive electrode plate and a battery were produced in the same manner as in Example 1, and various evaluations were performed.
- Example 16 (comparison) In the preparation of the positive electrode plate of (1) above, except that 1) only the NCM raw material powder 15 shown in Tables 1A to 1C was used instead of the mixed powder A, and 2) the firing temperature was set to 890 ° C. , A positive electrode plate and a battery were produced in the same manner as in Example 1, and various evaluations were performed.
- Example 17 In the preparation of the positive electrode plate of (1) above, NCM mixed powder L containing NCM raw material powders 7 and 13 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 90:10 instead of 1) mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 950 ° C., and various evaluations were performed.
- Example 18 In the preparation of the positive electrode plate of (1) above, the NCM mixed powder M containing the NCM raw material powders 7 and 13 shown in Tables 1A to 1C in a blending ratio (weight ratio) of 95: 5 instead of 1) the mixed powder A.
- a positive electrode plate and a battery were produced in the same manner as in Example 1 except that 2) the firing temperature was set to 950 ° C., and various evaluations were performed.
- Results Table 2 shows the specifications of the positive electrode plates produced in each example and the evaluation results of the cells.
- XRD X-ray diffraction
- the batteries of Examples 1 to 13 using the positive electrode active material satisfying the requirements of the present invention showed a significantly higher cycle maintenance rate than the batteries of Examples 14 to 18 (comparative example) not satisfying the requirements of the present invention. ..
- Example 19 to 33> The example described below is an example relating to an all-solid-state secondary battery in which the positive electrode and the negative electrode are in the form of a mixture.
- Example 19 (1) Preparation of positive electrode active material powder Commercially available (Ni 0.3 Co 0.6 Mn 0.1 ) (OH) 2 powder (Ni 0.3 Co 0.6 Mn 0.1) (OH) 2 powders weighed so that the molar ratio of Li / (Ni + Co + Mn) is 1.07. After mixing Li 2 CO 3 powder (average particle size 3 ⁇ m) with an average particle size of 9 to 10 ⁇ m, the mixture was held at 950 ° C. for 10 hours to obtain an NCM raw material powder 23.
- the obtained NCM raw material powder 23 is added with 1.0% by weight of Li 3 BO 3 (relative to the total amount of NCM raw material powder 23 and Li 3 BO 3 ) and Li 3 PO 4 (with respect to the total amount of NCM raw material powder 23 and Li 3 PO 3). After adding 1.0% by weight (to the total amount of 4 ) and mixing, the mixture was held at 950 ° C. for 10 hours to obtain an NCM powder.
- the filling rate (% by volume) of the active material in each of the positive electrode and the negative electrode of the all-solid-state battery manufactured in (4) above was measured as follows. First, after polishing the cross section of the all-solid-state battery by ion milling, the cross section of the polished positive electrode (or negative electrode) was observed by SEM to obtain a cross-sectional SEM image. The SEM image was an image with a magnification of 1000 times. The obtained image was binarized using image analysis software (Image-Pro Premier manufactured by Media Cybernetics). The threshold value for binarization was set using Otsu's binarization as a discriminant analysis method.
- Example 20 The negative electrode active material powder was prepared as follows, and in the charge / discharge evaluation of (5c) above, the discharge capacity of the battery at an operating temperature of 150 ° C. was measured in the voltage range of 2.7V-1.5V. Except for the above, the batteries were prepared and evaluated in the same manner as in Example 19.
- Example 21 In the preparation of the positive electrode active material powder of (1) above, Li 3 BO 3 is added to the NCM raw material powder 23 (relative to the total amount of the NCM raw material powder 23 and Li 3 BO 3 ) in an amount of 1.0% by weight, Li 3 PO 4 . The same as in Example 19 except that 2.5% by weight (relative to the total amount of NCM raw material powder 23 and Li 3 PO 4 ) was added and mixed, and then the mixture was held at 950 ° C. for 10 hours to obtain NCM powder. The battery was manufactured and evaluated.
- Example 22 In the preparation of the positive electrode active material powder of (1) above, Li 3 BO 3 is added to the NCM raw material powder 23 (relative to the total amount of the NCM raw material powder 23 and Li 3 BO 3 ) in an amount of 1.0% by weight, Li 3 PO 4 . The same as in Example 19 except that 5.0% by weight (relative to the total amount of the NCM raw material powder 23 and Li 3 PO 4 ) was added and mixed, and then the mixture was held at 950 ° C. for 10 hours to obtain an NCM powder. The battery was manufactured and evaluated.
- Example 23 In the preparation of the positive electrode active material powder of (1) above, 1.0% by weight of Li 3 PO 4 (relative to the total amount of the NCM raw material powder 23 and Li 3 PO 4 ) was added to the NCM raw material powder 23 and mixed. , The battery was prepared and evaluated in the same manner as in Example 19 except that the NCM powder was obtained by holding at 950 ° C. for 10 hours.
- Example 24 In the preparation of the positive electrode active material powder of (1) above, 5.0% by weight of Li 3 PO 4 (relative to the total amount of the NCM raw material powder 23 and Li 3 PO 4 ) was added to the NCM raw material powder 23 and mixed. , The battery was prepared and evaluated in the same manner as in Example 19 except that the NCM powder was obtained by holding at 950 ° C. for 10 hours.
- Example 25 In the preparation of the positive electrode active material powder of (1) above, 1.0% by weight of Li 2 SO 4 (relative to the total amount of the NCM raw material powder 23 and Li 2 SO 4 ) was added to the NCM raw material powder 23 and mixed. , The battery was prepared and evaluated in the same manner as in Example 19 except that the NCM powder was obtained by holding at 950 ° C. for 10 hours.
- Example 26 In the preparation of the positive electrode active material powder of (1) above, after adding 5.0% by weight of Li 2 SO 4 (relative to the total amount of the NCM raw material powder 23 and Li 2 SO 4 ) to the NCM raw material powder 23 and mixing. , The battery was prepared and evaluated in the same manner as in Example 19 except that the NCM powder was obtained by holding at 950 ° C. for 10 hours.
- Example 27 In the preparation of the positive electrode active material powder of (1) above, after adding 1.0% by weight of Li 3 BO 3 (relative to the total amount of the NCM raw material powder 23 and Li 3 BO 3 ) to the NCM raw material powder 23 and mixing. , The battery was prepared and evaluated in the same manner as in Example 19 except that the NCM powder was obtained by holding at 950 ° C. for 10 hours.
- Example 28 In the preparation of the positive electrode active material powder of (1) above, after adding 5.0% by weight of Li 3 BO 3 (relative to the total amount of the NCM raw material powder 23 and Li 3 BO 3 ) to the NCM raw material powder 23 and mixing. , The battery was prepared and evaluated in the same manner as in Example 19 except that the NCM powder was obtained by holding at 950 ° C. for 10 hours.
- Example 29 Batteries were prepared and evaluated in the same manner as in Example 19 except that the positive electrode active material powder was prepared as follows.
- Example 30 In the preparation of the positive electrode active material powder of (1') above, 1.0% by weight of Li 3 PO 4 (relative to the total amount of the NCM raw material powder 24 and Li 3 PO 4 ) was added to the NCM raw material powder 24 and mixed. After that, the batteries were prepared and evaluated in the same manner as in Example 29 except that the NCM powder was obtained by holding at 920 ° C. for 10 hours.
- Example 31 (Comparison) Except for the addition of Li 3 BO 3 and Li 3 PO 4 and the subsequent heat treatment not performed in the preparation of the positive electrode active material powder in (1) above (that is, the NCM raw material powder 23 was used as it is as the positive electrode active material powder). Made and evaluated the battery in the same manner as in Example 19.
- Example 32 (comparison) Except for the addition of Li 3 BO 3 and Li 3 PO 4 and the subsequent heat treatment not performed in the preparation of the positive electrode active material powder in (1) above (that is, the NCM raw material powder 23 was used as it is as the positive electrode active material powder). Made and evaluated the battery in the same manner as in Example 20.
- Example 33 (Comparison) In the preparation of the positive electrode active material powder of (1') above, the addition of Li 3 BO 3 and Li 3 PO 4 and the subsequent heat treatment were not performed (that is, the NCM raw material powder 24 was used as it is as the positive electrode active material powder). Except for the above, the batteries were prepared and evaluated in the same manner as in Example 29.
- Results Table 3 shows the specifications of the mixed material cells produced in each example and the evaluation results of the cells.
- XRD X-ray diffraction
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Abstract
Description
前記正極活物質は、Li、Ni、Co及びMnを含む層状岩塩構造を有するリチウム複合酸化物を含み、なおかつ、Li3BO3、Li3PO4及びLi2SO4から選択される少なくとも1つの添加剤をさらに含む、正極活物質が提供される。
前記正極活物質を含む正極層と、
負極活物質を含む負極層と、
前記正極層と前記負極層との間に介在する、LiOH・Li2SO4系固体電解質と、
を含む、リチウムイオン二次電池が提供される。
本発明による正極活物質は、リチウムイオン二次電池に用いられるものである。この正極活物質は、Li、Ni、Co及びMnを含む層状岩塩構造を有するリチウム複合酸化物を含む。そして、この正極活物質は、Li3BO3、Li3PO4及びLi2SO4から選択される少なくとも1つの添加剤をさらに含む。このように、リチウムイオン二次電池に用いられるリチウム複合酸化物に、Li3BO3、Li3PO4及びLi2SO4から選択される少なくとも1つの添加剤を含有させることにより、サイクル特性(特にサイクル維持率)を大幅に向上させることができる。
本発明の好ましい態様によるリチウム複合酸化物焼結板はいかなる方法で製造されたものであってもよいが、好ましくは、(a)NCM原料粉末の作製、(b)NCMグリーンシートの作製、及び(c)NCMグリーンシートの焼成を経て製造される。
まず、NCM原料粉末を作製する。好ましいNCM原料粉末はLi(Ni0.5Co0.2Mn0.3)O2粉末、又はLi(Ni0.3Co0.6Mn0.1)O2粉末である。Li(Ni0.5Co0.2Mn0.3)O2粉末は、Li/(Ni+Co+Mn)のモル比が1.00~1.30となるように秤量された(Ni0.5Co0.2Mn0.3)(OH)2粉末とLi2CO3粉末を混合後、700~1200℃(好ましくは750~1000℃)で1~24時間(好ましくは2~15時間)焼成することにより作製することができる。また、Li(Ni0.3Co0.6Mn0.1)O2粉末は、Li/(Ni+Co+Mn)のモル比が1.00~1.30となるように秤量された(Ni0.3Co0.6Mn0.1)(OH)2粉末とLi2CO3粉末を混合後、700~1200℃(好ましくは750~1000℃)で1~24時間(好ましくは2~15時間)焼成することにより好ましく作製することができる。
NCM原料粉末(好ましくは上述したNCM混合粉末)、溶媒、バインダー、可塑剤、及び分散剤を混合してペーストとする。得られたペーストを粘度調整した後、シート状に成形することによってNCMグリーンシートを作製する。
こうして作製したNCMグリーンシートを所望のサイズ及び形状に切り出し、焼成用鞘内に載置して焼成を行う。焼成は、昇温速度50~600℃/h(好ましくは100~300℃/h)で、800~1000℃(好ましくは850~970℃)に昇温して1~24時間(好ましくは2~12時間)保持することにより行うのが望ましい。こうしてリチウム複合酸化物焼結板(NCM焼結板)が得られる。
本発明による正極活物質は、リチウムイオン二次電池(典型的には全固体電池)に用いられるものである。したがって、本発明の好ましい態様によれば、本発明の正極活物質を含む正極層と、負極層と、LiOH・Li2SO4系固体電解質とを備えるリチウムイオン二次電池が提供される。負極層は負極活物質を含む。LiOH・Li2SO4系固体電解質は、正極層と負極層との間に介在する。上述したように、Li3BO3、Li3PO4及び/又はLi2SO4が添加されたリチウム複合酸化物を正極層に用いたリチウムイオン二次電池は、従来の添加剤無添加のリチウム複合酸化物を正極層に用いたリチウムイオン二次電池よりも、高いサイクル維持率を呈することができる。
リチウムイオン二次電池の製造は、焼結板電極を用いる場合、i)(必要に応じて集電体を形成した)正極と(必要に応じて集電体を形成した)負極とを準備し、ii)正極と負極との間に固体電解質を挟んで加圧や加熱等を施して正極、固体電解質及び負極を一体化させることにより行うことができる。正極、固体電解質、及び負極は他の手法により結合されてもよい。この場合、正極と負極の間に固体電解質を形成させる手法の例としては、一方の電極上に固体電解質の成形体や粉末を載置する手法、電極上に固体電解質粉末のペーストをスクリーン印刷で施す手法、電極を基板としてエアロゾルディポジション法等により固体電解質の粉末を衝突固化させる手法、電極上に電気泳動法により固体電解質粉末を堆積させて成膜する手法等が挙げられる。一方、合材電極を用いる場合における全固体二次電池の製造は、例えば、正極合材粉(正極活物質粒子、固体電解質粒子、及び電子伝導助剤を含む)、固体電解質粉末、及び負極合材粉(負極活物質粒子、固体電解質粒子、及び電子伝導助剤を含む)をそれぞれプレス型に投入して加圧することにより行うことができる。この場合における各種粉末の投入及び加圧は、最終的に正極層、固体電解質層、負極層の順になるように任意の順序で行えばよい。なお、前述のとおり、正極活物質粒子は、リチウム複合酸化物の粉末と、Li3BO3、Li3PO4及びLi2SO4から選択される少なくとも1つの粉末とを含む、混合粉末の形態でありうる。
以下に説明する例は、正極及び負極が焼結板の形態である全固体二次電池に関する例である。
Li/(Ni+Co+Mn)のモル比が1.15となるように秤量された市販の(Ni0.5Co0.2Mn0.3)(OH)2粉末(平均粒径9~10μm)とLi2CO3粉末(平均粒径3μm)を混合後、750℃で10時間保持し、NCM原料粉末1を得た。この粉末の体積基準D50粒径は8μmであった。
NCM原料粉末1にLi3BO3を(NCM原料粉末1及びLi3BO3の合計量に対して)2.45重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末2を得た。
NCM原料粉末1にLi3BO3を(NCM原料粉末1及びLi3BO3の合計量に対して)9.2重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末3を得た。
NCM原料粉末1をボールミルの湿式粉砕にて体積基準D50粒径を約5.5μmに調整した後、乾燥してNCM原料粉末4を得た。
NCM原料粉末1にLi3PO4を(NCM原料粉末1及びLi3PO4の合計量に対して)1.0重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約5.5μmに調整した後、乾燥してNCM原料粉末5を得た。
NCM原料粉末1にLi3PO4を(NCM原料粉末1及びLi3PO4の合計量に対して)5.0重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約5.5μmに調整した後、乾燥してNCM原料粉末6を得た。
Li/(Ni+Co+Mn)のモル比が1.15となるように秤量された市販の(Ni0.3Co0.6Mn0.1)(OH)2粉末(平均粒径7~8μm)とLi2CO3粉末(平均粒径3μm)を混合後、850℃で10時間保持し、NCM原料粉末7を得た。この粉末の体積基準D50粒径は6.5μmであった。
NCM原料粉末7にLi3BO3を(NCM原料粉末7及びLi3BO3の合計量に対して)9.2重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末8を得た。
NCM原料粉末7にLi3BO3を(NCM原料粉末7及びLi3BO3の合計量に対して)16.8重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末9を得た。
NCM原料粉末7にLi3BO3を(NCM原料粉末7及びLi3BO3の合計量に対して)51重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末10を得た。
NCM原料粉末7にLi2SO4を(NCM原料粉末7及びLi2SO4の合計量に対して)16.8重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末11を得た。
NCM原料粉末7にLi2SO4を(NCM原料粉末7及びLi2SO4の合計量に対して)51重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末12を得た。
NCM原料粉末7をボールミルの湿式粉砕にて体積基準D50粒径を約0.4μmに調整した後、乾燥してNCM原料粉末13を得た。
NCM原料粉末7をボールミルの湿式粉砕にて体積基準D50粒径を約4.3μmに調整した後、乾燥してNCM原料粉末14を得た。
Li/(Ni+Co+Mn)のモル比が1.15となるように秤量された市販の(Ni0.3Co0.6Mn0.1)(OH)2粉末(平均粒径7~8μm)とLi2CO3粉末(平均粒径3μm)を混合後、950℃で10時間保持し、得られた粉末をボールミルの湿式粉砕にて体積基準D50粒径を約1.9μmに調整した後、乾燥してNCM原料粉末15を得た。
Li/(Ni+Co+Mn)のモル比が1.15となるように秤量された市販の(Ni0.3Co0.6Mn0.1)(OH)2粉末(平均粒径9~10μm)とLi2CO3粉末(平均粒径3μm)にLi3PO4粉末(平均粒径0.5μm)を(NCM水酸化物とLi2CO3及びLi3PO4の合計量に対して)0.74重量%加え混合後、870℃で10時間保持し、NCM原料粉末16を得た。この粉末の体積基準D50粒径は7.4μmであった。
Li/(Ni+Co+Mn)のモル比が1.15となるように秤量された市販の(Ni0.3Co0.6Mn0.1)(OH)2粉末(平均粒径9~10μm)とLi2CO3粉末(平均粒径3μm)にLi3PO4粉末(平均粒径0.5μm)を(NCM水酸化物とLi2CO3及びLi3PO4の合計量に対して)1.8重量%加え混合後、870℃で10時間保持し、NCM原料粉末17を得た。この粉末の体積基準D50粒径は7.5μmであった。
Li/(Ni+Co+Mn)のモル比が1.15となるように秤量された市販の(Ni0.3Co0.6Mn0.1)(OH)2粉末(平均粒径9~10μm)とLi2CO3粉末(平均粒径3μm)にLi3PO4粉末(平均粒径0.5μm)を(NCM水酸化物とLi2CO3及びLi3PO4の合計量に対して)3.6重量%加え混合後、870℃で10時間保持し、NCM原料粉末18を得た。この粉末の体積基準D50粒径は7.7μmであった。
Li/(Ni+Co+Mn)のモル比が1.15となるように秤量された市販の(Ni0.3Co0.6Mn0.1)(OH)2粉末(平均粒径9~10μm)とLi2CO3粉末(平均粒径3μm)を混合後、750℃で10時間保持し、NCM原料粉末19を得た。この粉末の体積基準D50粒径は7.0μmであった。
NCM原料粉末19にLi3BO3を(NCM原料粉末19及びLi3BO3の合計量に対して)9.2重量%、Li3PO4を(NCM原料粉末19及びLi3PO4の合計量に対して)1.0重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.5μmに調整した後、乾燥してNCM原料粉末20を得た。
NCM原料粉末19にLi3BO3を(NCM原料粉末19及びLi3BO3の合計量に対して)9.2重量%、Li3PO4を(NCM原料粉末19及びLi3PO4の合計量に対して)2.5重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.5μmに調整した後、乾燥してNCM原料粉末21を得た。
NCM原料粉末19にLi3BO3を(NCM原料粉末19及びLi3BO3の合計量に対して)9.2重量%、Li3PO4を(NCM原料粉末19及びLi3PO4の合計量に対して)5.0重量%加え、ボールミルの湿式粉砕にて体積基準D50粒径を約0.5μmに調整した後、乾燥してNCM原料粉末22を得た。
(1)正極板の作製
(1a)NCMグリーンシートの作製
まず、表1A~1Cに示されるようにNCM原料粉末1及び2を80:20の配合割合(重量比)で均一に混合してNCM混合粉末Aを用意した。この混合粉末Aと、テープ成形用の溶媒、バインダー、可塑剤、及び分散剤とを混合した。得られたペーストを粘度調整した後、PET(ポリエチレンテレフタレート)フィルム上にシート状に成形することによってNCMグリーンシートを作製した。NCMグリーンシートの厚さは焼成後の厚さが100μmとなるように調整した。
PETフィルムから剥がしたNCMグリーンシートをポンチで直径11mmの円形に抜き出し、焼成用鞘内に載置した。昇温速度200℃/hで940℃まで昇温して10時間保持することで焼成を行った。得られた焼結板の厚さはSEM観察より、約100μmであった。このNCM焼結板の片面にスパッタリングによりAu膜(厚さ100nm)を集電層として形成した。こうして、正極板を得た。
(2a)LTOグリーンシートの作製
Li/Tiのモル比が0.84となるように秤量された市販のTiO2粉末(平均粒径1μm以下)とLi2CO3粉末(平均粒径3μm)を混合後、1000℃で2時間保持し、LTO粒子からなる粉末を得た。この粉末をボールミルの湿式粉砕にて平均粒径約2μmに調整した後、テープ成形用の溶媒、バインダー、可塑剤及び分散剤と混合した。得られたペーストの粘度を調整した後、このペーストをPETフィルム上にシート状に成形することによってLTOグリーンシートを作製した。LTOグリーンシートの厚さは焼成後の厚さが130μmとなるように調整した。
PETフィルムから剥がしたLTOグリーンシートをポンチで直径11mmの円形に抜き出し、焼成用鞘内に載置した。昇温速度200℃/hで850℃まで昇温して2時間保持することで焼成を行った。得られた焼結板の厚さはSEM観察より、約130μmであった。このLTO焼結板の片面にスパッタリングによりAu膜(厚さ100nm)を集電層として形成した。こうして、負極板を得た。
(3a)原料混合粉末の準備
Li2SO4粉末(市販品、純度99%以上)、LiOH粉末(市販品、純度98%以上)、及びLi3BO3(市販品、純度99%以上)をLi2SO4:LiOH:Li3BO3=1:2.6:0.05(モル比)となるように混合して原料混合粉末を得た。これらの粉末は、Ar雰囲気中のグローブボックス内で取り扱い、吸湿等の変質が起こらないように十分に注意した。
Ar雰囲気中で原料混合粉末を高純度アルミナ製のるつぼに投入した。このるつぼを電気炉にセットし、430℃で2時間、Ar雰囲気で熱処理を行い溶融物を作製した。引き続き、電気炉内にて100℃/hで溶融物を冷却して凝固物を形成した。
得られた凝固物をAr雰囲気中のグローブボックス内で乳鉢にて粉砕することによって、体積基準D50粒径が5~50μmの固体電解質粉末を得た。
正極板上に固体電解質粉末を載置し、その上に負極板を載置した。更に負極板上に重しを載置し、電気炉内で400℃で45分間加熱した。このとき、固体電解質粉末は溶融し、その後の凝固を経て電極板間に固体電解質層が形成された。得られた正極板/固体電解質/負極板で構成されるセルを用いて電池を作製した。
(5a)配向度
上記(1)で作製された正極板に対してXRD(X線回折)測定を行った。この測定は、XRD装置(BRUKER社製、D8 ADVANCE)を用い、正極板の板面に対してX線を照射したときのXRDプロファイルを測定することにより行った。このXRDプロファイルから、NCMの(104)面に起因する回折強度(ピーク高さ)I[104]に対する(003)面に起因する回折強度(ピーク高さ)I[003]の比率であるI[003]/I[104]を算出し、これを配向度とした。
上記(1)で作製された正極板(固体電解質を含まない状態のNCM焼結板)と上記(2)で作製された負極板(固体電解質を含まない状態のLTO焼結板)のそれぞれの厚さ及び気孔率(体積%)を以下のようにして測定した。まず、正極板(又は負極板)を樹脂埋め後、イオンミリングにより断面研磨した後、研磨された断面をSEMで観察して断面SEM画像を取得した。このSEM画像より厚さを算出した。気孔率測定のSEM画像は、倍率1000倍及び500倍の画像とした。得られた画像に対し、画像解析ソフト(Media Cybernetics社製、Image-Pro Premier)を用いて、2値化処理を行い、正極板(又は負極板)における、正極活物質(又は負極活物質)の部分と樹脂で充填された部分(もともと気孔であった部分)の合計面積に占める、樹脂で充填された部分の面積の割合(%)を算出して正極板(又は負極板)の気孔率(%)とした。2値化する際の閾値は、判別分析法として大津の2値化を用いて設定した。正極板の気孔率は表2に示されるとおりであり、負極板の気孔率は38%(すなわち緻密度62%)であった。
上記の気孔率測定に使用したSEM画像を用い、以下のようにして平均気孔径を測定した。画像解析ソフト(Media Cybernetics社製、Image-Pro Premier)を用いて、2値化処理を行い、正極板(又は負極板)における、正極活物質(又は負極活物質)の部分と樹脂で充填された部分(もともと気孔であった部分)を切り分けた。その後、樹脂で充填された部分の領域において、各領域の最大マーチン径を求め、それらの平均値を正極板(又は負極板)の平均気孔径(μm)とした。正極板の平均気孔径は表2に示されるとおりであり、負極板の平均気孔径は2.1μmであった。
上記の気孔率測定に使用したSEM画像を用い、以下のようにして単位断面積1μm2当たりの界面長を測定した。画像解析ソフト(Media Cybernetics社製、Image-Pro Premier)を用いて、2値化処理を行い、正極板における、正極活物質の部分と樹脂で充填された部分(もともと気孔であった部分)を切り分けた。その後、樹脂で充填された部分の領域において、全領域の周囲長(すなわち正極活物質の部分と樹脂で充填された部分との界面の合計長さ)と、解析した全領域(すなわち正極活物質の部分と樹脂で充填された部分の両方からなる領域)の面積を求めた。周囲長を、解析した全領域の面積で除し、単位断面積1μm2当たりの界面長(μm)とした。結果を表2に示す。
上記(1)で作製された正極板におけるLi含有量のNi、Co及びMnの合計含有量に対するモル比率Li/(Ni+Co+Mn)を、誘導結合プラズマ発光分光分析法(ICP-AES法)による金属元素分析の測定結果から算出した。結果を表2に示す。
上記(3c)で得られたLiOH・Li2SO4系固体電解質をX線回折(XRD)で解析したところ、3LiOH・Li2SO4と同定された。
上記(4)で作製された電池について、150℃の作動温度における電池の放電容量を2.5V-1.5Vの電圧範囲において測定した。この測定は、電池電圧が上記電圧範囲の上限に達するまで定電流定電圧充電した後、上記電圧範囲の下限になるまで放電することにより行った。この試験を繰り返し行い(サイクル試験)、所定サイクル時の放電容量の維持率(=100×(所定サイクル時の放電容量)/(初回の放電容量))を算出した。結果を表2に示す。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末1及び3を90:10の配合割合(重量比)で含むNCM混合粉末Bを用いたこと、及び2)焼成温度を950℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末5のみを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。また、本例で作製された電池をグローブボックス内で解体し、正極板と固体電解質の界面に対して、電子顕微鏡観察及び電子プローブマイクロアナライザ(EPMA)による元素マッピングを行った。図1に、本例で作製された全固体電池の正極活物質(NCM)/固体電解質断面の電子顕微鏡写真及びEPMAマッピング像を示す。図1において最も左に位置する画像が電子顕微鏡写真(白い部分がNCM、黒い部分が固体電解質に相当)であり、そこから右に向かってMn、Co、及びNiのEPMAマッピング像が順に示される。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末6のみを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び8を90:10の配合割合(重量比)で含むNCM混合粉末Cを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び8を95:5の配合割合(重量比)で含むNCM混合粉末Dを用いたこと、及び2)焼成温度を950℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び9を95:5の配合割合(重量比)で含むNCM混合粉末Eを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び10を95:5の配合割合(重量比)で含むNCM混合粉末Fを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。また、図3に、本例で作製された正極板断面の電子顕微鏡写真(反射電子像)を示す。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び11を95:5の配合割合(重量比)で含むNCM混合粉末Gを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び12を95:5の配合割合(重量比)で含むNCM混合粉末Hを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末16及び20を90:10の配合割合(重量比)で含むNCM混合粉末Iを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末17及び21を90:10の配合割合(重量比)で含むNCM混合粉末Jを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。また、図4に、本例で作製された正極板の樹脂埋め後における、正極板断面の電子顕微鏡写真(反射電子像)を示す。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末18及び22を90:10の配合割合(重量比)で含むNCM混合粉末Kを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末4のみを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。また、本例で作製された電池をグローブボックス内で解体し、正極板と固体電解質の界面に対して、電子顕微鏡観察及び電子プローブマイクロアナライザ(EPMA)による元素マッピングを行った。図2に、本例で作製された全固体電池の正極活物質(NCM)/固体電解質断面の電子顕微鏡写真及びEPMAマッピング像を示す。図2において最も左に位置する画像が電子顕微鏡写真(白い部分がNCM、黒い部分が固体電解質に相当)であり、そこから右に向かってMn、Co、及びNiのEPMAマッピング像が順に示される。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末14のみを用いたこと、及び2)焼成温度を920℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末15のみを用いたこと、及び2)焼成温度を890℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び13を90:10の配合割合(重量比)で含むNCM混合粉末Lを用いたこと、及び2)焼成温度を950℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
上記(1)の正極板の作製において、1)混合粉末Aの代わりに、表1A~1Cに示されるNCM原料粉末7及び13を95:5の配合割合(重量比)で含むNCM混合粉末Mを用いたこと、及び2)焼成温度を950℃としたこと以外は、例1と同様にして正極板及び電池を作製し、各種評価を行った。
表2に各例で作製した正極板の仕様及びセルの評価結果を示す。なお、充放電特性は同レート同サイクル数で比較し、所定サイクル時の放電容量の維持率(=100×(所定サイクル時の放電容量)/(初回の放電容量))を算出して表2に示した。なお、各例にてLiOH・Li2SO4系固体電解質をX線回折(XRD)で解析したところ、3LiOH・Li2SO4と同定された。
以下に説明する例は、正極及び負極が合材の形態である全固体二次電池に関する例である。
(1)正極活物質粉末の作製
Li/(Ni+Co+Mn)のモル比が1.07となるように秤量された市販の(Ni0.3Co0.6Mn0.1)(OH)2粉末(平均粒径9~10μm)とLi2CO3粉末(平均粒径3μm)を混合した後、950℃で10時間保持してNCM原料粉末23を得た。得られたNCM原料粉末23にLi3BO3を(NCM原料粉末23及びLi3BO3の合計量に対して)1.0重量%、Li3PO4を(NCM原料粉末23及びLi3PO4の合計量に対して)1.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得た。
市販のカーボン粉末(平均粒径10~14μm)を用意した。
(3a)原料粉末の準備
Li2SO4粉末(市販品、純度99%以上)、LiOH粉末(市販品、純度98%以上)、及びLi3BO3(市販品、純度99%以上)をLi2SO4:LiOH:Li3BO3=1:2.2:0.05(モル比)となるように混合して原料混合粉末を得た。これらの粉末は、Ar雰囲気中のグローブボックス内で取り扱い、吸湿等の変質が起こらないように十分に注意した。
Ar雰囲気中で原料混合粉末を高純度アルミナ製のるつぼに投入した。このるつぼを電気炉にセットし、430℃で2時間、Ar雰囲気で熱処理を行い溶融物を作製した。引き続き、電気炉内にて100℃/hで溶融物を冷却して凝固物を形成した。
得られた凝固物をAr雰囲気中のグローブボックス内で乳鉢にて粉砕し、さらに玉石を用いた粉砕により、平均粒径D50が1~20μmの固体電解質粉末を得た。
(4a)正極合材粉及び負極合材粉の作製
上記(1)で得られた正極活物質粉末と、上記(3)で得られた固体電解質粉末と、電子伝導助剤(アセチレンブラック(市販品))とを体積比で60:40:2となるように秤量し、これらを乳鉢で混合して正極合材粉を作製した。同様に、上記(2)で得られた負極活物質粉末と、上記(3)で得られた固体電解質粉末と、電子伝導助剤(アセチレンブラック(市販品))とを体積比で60:40:2となるように秤量し、これらを乳鉢で混合して負極合材粉を作製した。
穴径10mmのプレス型に正極層、固体電解質層、負極層の順で、それぞれ100μm、500μm、110μmの厚さとなるように、各層につき粉末の投入及び100MPaでの加圧を行った。こうして3層を積層した後に積層体を150MPaで加圧して、プレス成形体を得た。
プレス成形体を、ステンレス板/正極層/固体電解質層/負極層/ステンレス板の層構成となるように1対のステンレス板で挟み、プレス成形体をステンレス板ごと150MPaで保持した状態とし、評価用セルとしての全固体電池を得た。
(5a)正極層における金属元素のモル比の測定
上記(1)で作製された正極層におけるLi含有量のNi、Co及びMnの合計含有量に対するモル比率Li/(Ni+Co+Mn)を、誘導結合プラズマ発光分光分析法(ICP-AES法)による金属元素分析の測定結果から算出した。結果を表3に示す。
上記(3c)で得られたLiOH・Li2SO4系固体電解質をX線回折(XRD)で解析したところ、3LiOH・Li2SO4と同定された。
上記(4)で作製された電池について、150℃の作動温度における電池の放電容量を4.15V-2.0Vの電圧範囲において測定した。この測定は、電池電圧が上記電圧範囲の上限に達するまで定電流定電圧充電した後、上記電圧範囲の下限になるまで放電することにより行った。この試験を繰り返し行い(サイクル試験)、所定サイクル時の放電容量の維持率(=100×(所定サイクル時の放電容量)/(初回の放電容量))を算出した。結果を表3に示す。
上記(4)で作製された全固体電池の正極と負極のそれぞれにおける活物質の充填率(体積%)を以下のようにして測定した。まず、全固体電池をイオンミリングにより断面研磨した後、研磨された正極(又は負極)の断面をSEMで観察して断面SEM画像を取得した。SEM画像は、倍率1000倍の画像とした。得られた画像に対し、画像解析ソフト(Media Cybernetics社製、Image-Pro Premier)を用いて2値化処理を行った。2値化する際の閾値は、判別分析法として大津の2値化を用いて設定した。得られた2値化画像に基づいて、正極(又は負極)における正極活物質(又は負極活物質)の充填率F(%)を以下の式:
充填率F=[SA/(SA+SB)]×100
(式中、SAは2値化画像における正極活物質(又は負極活物質)が占める部分の面積であり、SBは2値化画像における正極活物質(又は負極活物質)以外の部分の面積であり固体電解質、電子伝導助剤及び空隙が占める面積を含む)
により算出した。結果を表3に示す。
以下のようにして負極活物質粉末の作製を行ったこと、及び上記(5c)の充放電評価において、150℃の作動温度における電池の放電容量を2.7V-1.5Vの電圧範囲において測定したこと以外は、例19と同様にして電池の作製及び評価を行った。
Li/Tiのモル比が0.84となるように秤量された市販のTiO2粉末(平均粒径1μm以下)とLi2CO3粉末(平均粒径3μm)を混合後、1000℃で2時間保持し、LTO粒子からなる平均粒径約3.5μmの粉末を得た。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi3BO3を(NCM原料粉末23及びLi3BO3の合計量に対して)1.0重量%、Li3PO4を(NCM原料粉末23及びLi3PO4の合計量に対して)2.5重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi3BO3を(NCM原料粉末23及びLi3BO3の合計量に対して)1.0重量%、Li3PO4を(NCM原料粉末23及びLi3PO4の合計量に対して)5.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi3PO4を(NCM原料粉末23及びLi3PO4の合計量に対して)1.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi3PO4を(NCM原料粉末23及びLi3PO4の合計量に対して)5.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi2SO4を(NCM原料粉末23及びLi2SO4の合計量に対して)1.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi2SO4を(NCM原料粉末23及びLi2SO4の合計量に対して)5.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi3BO3を(NCM原料粉末23及びLi3BO3の合計量に対して)1.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製において、NCM原料粉末23にLi3BO3を(NCM原料粉末23及びLi3BO3の合計量に対して)5.0重量%加えて混合した後、950℃で10時間保持してNCM粉末を得たこと以外は、例19と同様にして電池の作製及び評価を行った。
以下のようにして正極活物質粉末の作製を行ったこと以外は、例19と同様にして電池の作製及び評価を行った。
Li/(Ni+Co+Mn)のモル比が1.05となるように秤量された市販の(Ni0.5Co0.2Mn0.3)(OH)2粉末(平均粒径9μm)とLi2CO3粉末(平均粒径3μm)を混合した後、920℃で10時間保持してNCM原料粉末24を得た。得られたNCM原料粉末24にLi3BO3を(NCM原料粉末24及びLi3BO3の合計量に対して)1.0重量%、Li3PO4を(NCM原料粉末24及びLi3PO4の合計量に対して)1.0重量%加えて混合した後、920℃で10時間保持してNCM粉末を得た。
上記(1’)の正極活物質粉末の作製において、NCM原料粉末24にLi3PO4を(NCM原料粉末24及びLi3PO4の合計量に対して)1.0重量%加えて混合した後、920℃で10時間保持してNCM粉末を得たこと以外は、例29と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製においてLi3BO3及びLi3PO4の添加及びその後の熱処理を行わなかったこと(すなわちNCM原料粉末23をそのまま正極活物質粉末として用いたこと)以外は、例19と同様にして電池の作製及び評価を行った。
上記(1)の正極活物質粉末の作製においてLi3BO3及びLi3PO4の添加及びその後の熱処理を行わなかったこと(すなわちNCM原料粉末23をそのまま正極活物質粉末として用いたこと)以外は、例20と同様にして電池の作製及び評価を行った。
上記(1’)の正極活物質粉末の作製においてLi3BO3及びLi3PO4の添加及びその後の熱処理を行わなかったこと(すなわちNCM原料粉末24をそのまま正極活物質粉末として用いたこと)以外は、例29と同様にして電池の作製及び評価を行った。
表3に各例で作製した合材セルの仕様及びセルの評価結果を示す。なお、充放電特性は同レート同サイクル数で比較し、所定サイクル時の放電容量の維持率(=100×(所定サイクル時の放電容量)/(初回の放電容量))を算出して表3に示した。なお、各例にてLiOH・Li2SO4系固体電解質をX線回折(XRD)で解析したところ、3LiOH・Li2SO4と同定された。
Claims (16)
- リチウムイオン二次電池に用いられる正極活物質であって、
前記正極活物質は、Li、Ni、Co及びMnを含む層状岩塩構造を有するリチウム複合酸化物を含み、なおかつ、Li3BO3、Li3PO4及びLi2SO4から選択される少なくとも1つの添加剤をさらに含む、正極活物質。 - 前記添加剤が、前記リチウム複合酸化物の粒界及び表面の少なくとも一部に析出した状態で存在している、請求項1に記載の正極活物質。
- 前記添加剤の含有量が、前記リチウム複合酸化物及び前記添加剤の合計含有量に対して、0.1~10重量%である、請求項1又は2に記載の正極活物質。
- 前記正極活物質が焼結板の形態である、請求項1~3のいずれか一項に記載の正極活物質。
- 前記焼結板は、X線回折(XRD)によって測定されるXRDプロファイルにおける、(104)面に起因する回折強度I[104]に対する(003)面に起因する回折強度I[003]の比として定義される、配向度I[003]/I[104]が1.2~3.6である、請求項4に記載の正極活物質。
- 前記焼結板の、単位断面積1μm2当たりの界面長が0.45μm以下である、請求項4又は5のいずれか一項に記載の正極活物質。
- 前記焼結板の気孔率が20~40%である、請求項4~6のいずれか一項に記載の正極活物質。
- 前記焼結板の平均気孔径が3.5μm以上である、請求項4~7のいずれか一項に記載の正極活物質。
- 前記焼結板の厚さが30~300μmである、請求項4~8のいずれか一項に記載の正極活物質。
- 前記正極活物質が粉末の形態である、請求項1~3のいずれか一項に記載の正極活物質。
- 前記正極活物質におけるLi/(Ni+Co+Mn)のモル比が0.95~1.10である、請求項1~10のいずれか一項に記載の正極活物質。
- 請求項1~11のいずれか一項に記載の正極活物質を含む正極層と、
負極活物質を含む負極層と、
前記正極層と前記負極層との間に介在する、LiOH・Li2SO4系固体電解質と、
を含む、リチウムイオン二次電池。 - 前記正極活物質が焼結板の形態である、請求項12に記載のリチウムイオン二次電池。
- 前記正極層が、前記正極活物質の粒子、前記LiOH・Li2SO4系固体電解質の粒子、及び電子伝導助剤を合材の形態で含む、請求項12に記載のリチウムイオン二次電池。
- 前記負極活物質がLi4Ti5O12である、請求項12~14のいずれか一項に記載のリチウムイオン二次電池。
- 前記LiOH・Li2SO4系固体電解質がX線回折により3LiOH・Li2SO4と同定される固体電解質を含む、請求項12~15のいずれか一項に記載のリチウムイオン二次電池。
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PCT/JP2021/045009 WO2022138148A1 (ja) | 2020-12-22 | 2021-12-07 | 正極活物質及びリチウムイオン二次電池 |
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PCT/JP2021/013156 WO2022137583A1 (ja) | 2020-12-22 | 2021-03-26 | 正極活物質及びリチウムイオン二次電池 |
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Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006520525A (ja) * | 2003-03-14 | 2006-09-07 | スリーエム イノベイティブ プロパティズ カンパニー | リチウムイオン・カソード材料の製造方法 |
JP5601157B2 (ja) * | 2010-11-01 | 2014-10-08 | トヨタ自動車株式会社 | 正極活物質材料、正極活物質層、全固体電池および正極活物質材料の製造方法 |
WO2015151566A1 (ja) | 2014-03-31 | 2015-10-08 | 日本碍子株式会社 | 全固体リチウム電池 |
JP2018206609A (ja) * | 2017-06-05 | 2018-12-27 | 株式会社Gsユアサ | 非水電解質二次電池 |
WO2019093221A1 (ja) * | 2017-11-10 | 2019-05-16 | 日本碍子株式会社 | 二次電池 |
WO2019093222A1 (ja) | 2017-11-10 | 2019-05-16 | 日本碍子株式会社 | 全固体リチウム電池及びその製造方法 |
WO2019221140A1 (ja) * | 2018-05-17 | 2019-11-21 | 日本碍子株式会社 | リチウム二次電池 |
JP6780140B1 (ja) * | 2020-01-17 | 2020-11-04 | 住友化学株式会社 | 全固体リチウムイオン電池用混合粉末、全固体リチウムイオン電池用混合ペースト、電極および全固体リチウムイオン電池 |
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2020
- 2020-12-22 WO PCT/JP2020/048035 patent/WO2022137360A1/ja unknown
- 2020-12-22 JP JP2022570833A patent/JP7506767B2/ja active Active
- 2020-12-22 EP EP20966851.6A patent/EP4250402A1/en active Pending
- 2020-12-22 KR KR1020237008860A patent/KR20230051267A/ko unknown
- 2020-12-22 CN CN202080107474.XA patent/CN116438682A/zh active Pending
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2021
- 2021-03-26 WO PCT/JP2021/013156 patent/WO2022137583A1/ja active Application Filing
- 2021-12-07 JP JP2022572094A patent/JPWO2022138148A1/ja active Pending
- 2021-12-07 WO PCT/JP2021/045009 patent/WO2022138148A1/ja active Application Filing
- 2021-12-07 KR KR1020237008904A patent/KR20230051269A/ko active Search and Examination
- 2021-12-07 CN CN202180079355.2A patent/CN116569358A/zh active Pending
- 2021-12-07 EP EP21910297.7A patent/EP4270546A1/en active Pending
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2023
- 2023-05-25 US US18/323,608 patent/US20230299285A1/en active Pending
- 2023-06-05 US US18/328,903 patent/US20230307625A1/en active Pending
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006520525A (ja) * | 2003-03-14 | 2006-09-07 | スリーエム イノベイティブ プロパティズ カンパニー | リチウムイオン・カソード材料の製造方法 |
JP5601157B2 (ja) * | 2010-11-01 | 2014-10-08 | トヨタ自動車株式会社 | 正極活物質材料、正極活物質層、全固体電池および正極活物質材料の製造方法 |
WO2015151566A1 (ja) | 2014-03-31 | 2015-10-08 | 日本碍子株式会社 | 全固体リチウム電池 |
JP2018206609A (ja) * | 2017-06-05 | 2018-12-27 | 株式会社Gsユアサ | 非水電解質二次電池 |
WO2019093221A1 (ja) * | 2017-11-10 | 2019-05-16 | 日本碍子株式会社 | 二次電池 |
WO2019093222A1 (ja) | 2017-11-10 | 2019-05-16 | 日本碍子株式会社 | 全固体リチウム電池及びその製造方法 |
WO2019221140A1 (ja) * | 2018-05-17 | 2019-11-21 | 日本碍子株式会社 | リチウム二次電池 |
JP6780140B1 (ja) * | 2020-01-17 | 2020-11-04 | 住友化学株式会社 | 全固体リチウムイオン電池用混合粉末、全固体リチウムイオン電池用混合ペースト、電極および全固体リチウムイオン電池 |
Also Published As
Publication number | Publication date |
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WO2022137360A1 (ja) | 2022-06-30 |
KR20230051267A (ko) | 2023-04-17 |
CN116438682A (zh) | 2023-07-14 |
US20230299285A1 (en) | 2023-09-21 |
EP4250402A1 (en) | 2023-09-27 |
KR20230051269A (ko) | 2023-04-17 |
JPWO2022137360A1 (ja) | 2022-06-30 |
CN116569358A (zh) | 2023-08-08 |
JPWO2022138148A1 (ja) | 2022-06-30 |
WO2022137583A1 (ja) | 2022-06-30 |
JP7506767B2 (ja) | 2024-06-26 |
US20230307625A1 (en) | 2023-09-28 |
EP4270546A1 (en) | 2023-11-01 |
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