JP2022035366A - Positive electrode material for alkali metal ion battery, positive electrode, and alkali metal ion battery - Google Patents
Positive electrode material for alkali metal ion battery, positive electrode, and alkali metal ion battery Download PDFInfo
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- JP2022035366A JP2022035366A JP2020139620A JP2020139620A JP2022035366A JP 2022035366 A JP2022035366 A JP 2022035366A JP 2020139620 A JP2020139620 A JP 2020139620A JP 2020139620 A JP2020139620 A JP 2020139620A JP 2022035366 A JP2022035366 A JP 2022035366A
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- Prior art keywords
- positive electrode
- particles
- alkali metal
- metal ion
- ion battery
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- 229910001413 alkali metal ion Inorganic materials 0.000 title claims abstract description 48
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- 229910052748 manganese Inorganic materials 0.000 claims abstract description 10
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- 229910052759 nickel Inorganic materials 0.000 claims abstract description 6
- 239000003792 electrolyte Substances 0.000 claims description 6
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- IRXRGVFLQOSHOH-UHFFFAOYSA-L dipotassium;oxalate Chemical compound [K+].[K+].[O-]C(=O)C([O-])=O IRXRGVFLQOSHOH-UHFFFAOYSA-L 0.000 description 1
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- 229910000402 monopotassium phosphate Inorganic materials 0.000 description 1
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- YPEWWOUWRRQBAX-UHFFFAOYSA-N n,n-dimethyl-3-oxobutanamide Chemical compound CN(C)C(=O)CC(C)=O YPEWWOUWRRQBAX-UHFFFAOYSA-N 0.000 description 1
- 239000007773 negative electrode material Substances 0.000 description 1
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical group Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 1
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- 235000013855 polyvinylpyrrolidone Nutrition 0.000 description 1
- 235000011056 potassium acetate Nutrition 0.000 description 1
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 1
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- 235000011164 potassium chloride Nutrition 0.000 description 1
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 1
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Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- 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
Landscapes
- Battery Electrode And Active Subsutance (AREA)
Abstract
Description
本発明は、アルカリ金属イオン電池用正極材料、正極及びアルカリ金属イオン電池に関する。 The present invention relates to a positive electrode material for an alkali metal ion battery, a positive electrode, and an alkali metal ion battery.
電池のｘＥＶ搭載が進む中、電池のエネルギー密度の向上が望まれている。エネルギー密度改善のため、ＬｉＮｉＣｏＭｎＯ４、ＬｉＮｉＣｏＡｌＯ２等のリチウムを含有した酸化物系正極材料が広く用いられている。
ＬｉＮｉＣｏＭｎＯ４、ＬｉＮｉＣｏＡｌＯ２等のリチウムを含有した酸化物系正極材料を用いることで高いエネルギー密度の電池が得られるものの、リチウム資源は埋蔵量が乏しく、また資源偏在の問題があり、地政学上のリスクを抱えている。また、充放電中に発熱や酸素放出が生じ、過充電が行われた際に電池が故障するなどの問題がある。
上記資源問題の解決手段として、資源上の問題の大きいリチウムを資源上の問題の小さいカリウムに変更した正極材料が提唱されている（例えば、特許文献１参照）。
As the installation of xEV in batteries progresses, it is desired to improve the energy density of batteries. In order to improve the energy density, lithium-containing oxide-based positive electrode materials such as LiNiCoMnO 4 and LiNiCoAlO 2 are widely used.
Although a battery with a high energy density can be obtained by using an oxide-based positive electrode material containing lithium such as LiNiCoMnO 4 and LiNiCoAlO 2 , the lithium resource has a small reserve and there is a problem of uneven distribution of resources, so that it is geopolitical. I have a risk. Further, there is a problem that heat generation and oxygen release occur during charging / discharging, and the battery breaks down when overcharging is performed.
As a means for solving the above-mentioned resource problem, a positive electrode material in which lithium having a large resource problem is changed to potassium having a small resource problem has been proposed (see, for example, Patent Document 1).
カリウム含有型正極材料ＫＮｉＰＯ４、ＫＣｏＰＯ４のようなリン酸塩は、酸素とリンと強い共有結合性を有することから、充放電時の酸素放出が少なく、過充電が行われても電池の故障を抑制し得ることが期待される。しかしながら、ＫＮｉＰＯ４及びＫＣｏＰＯ４は電子伝導性に乏しく、従来報告されたＫＮｉＰＯ４及びＫＣｏＰＯ４ではその電池特性を十分に発現することが困難である。 Phosphates such as potassium-containing positive electrode materials KNiPO 4 and KCoPO 4 have a strong covalent bond with oxygen and phosphorus, so that oxygen release during charging and discharging is small, and even if overcharging is performed, the battery will fail. Is expected to be suppressed. However, KNiPO 4 and KCoPO 4 have poor electron conductivity, and it is difficult for the conventionally reported KNiPO 4 and KCoPO 4 to fully exhibit their battery characteristics.
本発明は、このような実情に鑑みてなされたものであり、従来報告されたＫＮｉＰＯ４及びＫＣｏＰＯ４に比べ、高いエネルギー密度が得られるアルカリ金属イオン電池、及び該電池を得ることができるアルカリ金属イオン電池用正極材料及び正極を提供することを目的とする。 The present invention has been made in view of such circumstances, and is an alkali metal ion battery capable of obtaining a higher energy density than the conventionally reported KNiPO 4 and KCoPO 4 , and an alkali metal capable of obtaining the battery. It is an object of the present invention to provide a positive electrode material for an ion battery and a positive electrode.
本発明者らは、上記の課題を解決するべく鋭意検討した結果、ＫＮｉＰＯ４、ＫＣｏＰＯ４等のリン酸カリウム化合物の粒子表面に導電性を有する炭素質被膜を被覆しつつ、所定のラマン特性備えることで、電子伝導性の低いＫＮｉＰＯ４及びＫＣｏＰＯ４であっても、電池作動可能な電子導電性を付与することができ、従来報告された炭素質未被膜の材料に比べ高い放電容量を発現することを見出した。
本発明は、かかる知見に基づいて完成したものである。
As a result of diligent studies to solve the above problems, the present inventors have a predetermined Raman property while coating the particle surface of a potassium phosphate compound such as KNiPO 4 or KCoPO 4 with a carbonaceous film having conductivity. As a result, even KNiPO 4 and KCoPO 4 , which have low electron conductivity, can be imparted with battery-operable electron conductivity, and exhibit higher discharge capacity than the conventionally reported carbonaceous uncoated materials. I found that.
The present invention has been completed based on such findings.
すなわち、本発明は、以下の［１］～［３］を提供する。
［１］ 一般式ＫｘＡｙＤｚＰＯ４で表される化合物の粒子と、前記粒子の表面を被覆する炭素質被膜とを有し、
ラマン分光測定で１５５０～１６５０ｃｍ－１に観測されるＧバンドの最大強度ＩＧに対する、９３０～１０３０ｃｍ－１に測定されるＰＯ４バンドの最大強度ＩＰＯ４の比ＩＰＯ４／ＩＧが０．０３≦ＩＰＯ４／ＩＧ≦０．３であるアルカリ金属イオン電池用正極材料。
但し、上記一般式において、ＡはＣｏ、Ｍｎ、及びＮｉからなる群から選択される少なくとも１種であり、ＤはＭｎ、Ｆｅ、Ｍｇ、Ｃａ、Ｓｒ、Ｂａ、Ｔｉ、Ｚｎ、Ｂ、Ａｌ、Ｇａ、Ｉｎ、Ｓｉ、Ｇｅ、Ｓｃ及びＹからなる群から選択される少なくとも１種であり、ｘ、ｙ、ｚは、０．９＜ｘ＜１．１、０．６５＜ｙ≦１．０、０≦ｚ＜０．３５、０．９＜ｙ＋ｚ＜１．１である。
［２］ 比表面積が５ｍ２／ｇ以上かつ３０ｍ２／ｇ以下である上記［１］に記載のアルカリ金属イオン電池用正極材料。
［３］ 上記［１］又は［２］に記載のアルカリ金属イオン電池用正極材料を用いた正極。
［４］ 上記［３］に記載の正極と、Ｌｉイオン、Ｎａイオン、及びＫイオンからなる群から選択される少なくとも１種を含む電解質とを有するアルカリ金属イオン電池。
That is, the present invention provides the following [1] to [3].
[1] It has particles of a compound represented by the general formula KxAyDzPO 4 and a carbonaceous coating that covers the surface of the particles.
The ratio of the maximum intensity IPO4 of the PO4 band measured from 930 to 1030 cm -1 to the maximum intensity IG of the G band observed from 1550 to 1650 cm -1 by Raman spectroscopy IPO4 / IG is 0.03 ≤ IPO4 / IG ≤ Positive electrode material for alkali metal ion batteries of 0.3.
However, in the above general formula, A is at least one selected from the group consisting of Co, Mn, and Ni, and D is Mn, Fe, Mg, Ca, Sr, Ba, Ti, Zn, B, Al, It is at least one selected from the group consisting of Ga, In, Si, Ge, Sc and Y, and x, y and z are 0.9 <x <1.1, 0.65 <y ≦ 1.0. , 0 ≦ z <0.35, 0.9 <y + z <1.1.
[2] The positive electrode material for an alkali metal ion battery according to the above [1], which has a specific surface area of 5 m 2 / g or more and 30 m 2 / g or less.
[3] A positive electrode using the positive electrode material for an alkali metal ion battery according to the above [1] or [2].
[4] An alkali metal ion battery comprising the positive electrode according to the above [3] and an electrolyte containing at least one selected from the group consisting of Li ion, Na ion, and K ion.
本発明によれば、従来報告されたＫＮｉＰＯ４及びＫＣｏＰＯ４に比べ、高いエネルギー密度が得られるアルカリ金属イオン電池、及び該電池を得ることができるアルカリ金属イオン電池用正極材料及び正極を提供することができる。 According to the present invention, an alkali metal ion battery capable of obtaining a higher energy density than the conventionally reported KNiPO 4 and KCoPO 4 , and a positive electrode material and a positive electrode for an alkali metal ion battery capable of obtaining the battery are provided. Can be done.
＜アルカリ金属イオン電池用正極材料＞
本実施形態のアルカリ金属イオン電池用正極材料（カリウム含有型正極材料と称することがある）は、一般式ＫｘＡｙＤｚＰＯ４で表される化合物の粒子と、前記粒子の表面を被覆する炭素質被膜とを有し、ラマン分光測定で１５５０～１６５０ｃｍ－１に観測されるＧバンドの最大強度ＩＧに対する、９３０～１０３０ｃｍ－１に測定されるＰＯ４バンドの最大強度ＩＰＯ４の比ＩＰＯ４／ＩＧが０．０３≦ＩＰＯ４／ＩＧ≦０．３である。
ＫＮｉＰＯ４、ＫＣｏＰＯ４等のリン酸カリウム化合物の粒子表面に導電性を有する炭素質被膜を被覆しつつ、所定のラマン特性備えることで、電子伝導性の低いＫＮｉＰＯ４及びＫＣｏＰＯ４等であっても、電池作動可能な電子導電性を付与することができ、従来報告された炭素質未被膜の材料に比べ高い放電容量を発現することができる。
本実施形態のカリウム含有型正極材料は、充放電可能な理論容量はリチウム含有酸化物材料に劣るものの、リチウム含有酸化物材料に比べ低い原料コストで製造することが可能である。また酸素とリンと強い共有結合性を有することから充放電時の酸素放出が少なく、過充電が行われても、電池の故障を抑制し得る。
<Positive material for alkali metal ion batteries>
The positive electrode material for an alkali metal ion battery (sometimes referred to as a potassium-containing positive electrode material) of the present embodiment comprises particles of a compound represented by the general formula KxAyDzPO 4 and a carbonaceous film covering the surface of the particles. The ratio IPO4 / IG of the maximum intensity IPO4 of the PO4 band measured from 930 to 1030 cm -1 to the maximum intensity IG of the G band observed from 1550 to 1650 cm -1 by Raman spectroscopy is 0.03 ≤ IPO4. / IG ≦ 0.3.
By covering the particle surface of potassium phosphate compounds such as KNiPO 4 and KCoPO 4 with a carbonaceous film having conductivity and having predetermined Raman characteristics, even KNiPO 4 and KCoPO 4 having low electron conductivity can be used. , Battery-operable electron conductivity can be imparted, and a higher discharge capacity can be exhibited as compared with the conventionally reported carbonaceous uncoated materials.
The potassium-containing positive electrode material of the present embodiment can be manufactured at a lower raw material cost than the lithium-containing oxide material, although the theoretical capacity that can be charged and discharged is inferior to that of the lithium-containing oxide material. Further, since it has a strong covalent bond with oxygen and phosphorus, oxygen release during charging and discharging is small, and even if overcharging is performed, battery failure can be suppressed.
〔ラマン特性〕
本実施形態のカリウム含有型正極材料は、ラマン分光測定で１５５０～１６５０ｃｍ－１に観測されるＧバンドの最大強度ＩＧに対する、９３０～１０３０ｃｍ－１に測定されるＰＯ４バンドの最大強度ＩＰＯ４の比ＩＰＯ４／ＩＧが０．０３≦ＩＰＯ４／ＩＧ≦０．３である。
比ＩＰＯ４／ＩＧは、化合物の粒子表面への炭素被覆状態を表す指標である。化合物の粒子表面の炭素被覆率が高く、粒子表面が炭素でおおわれているほど化合物粒子由来のＰＯ４バンドは小さくなり、一方で化合物の粒子表面の炭素被覆率が低く、粒子表面が露出しているほど化合物粒子由来のＰＯ４バンドは大きくなる。
比ＩＰＯ４／ＩＧが０．０３未満であると炭素の被覆状態が高くなりすぎた状態であり、アルカリ金属を含有する電解液と化合物の結晶表面の接触が阻害され、電池反応が阻害され十分な放電容量を得ることができない。一方で、０．３を超えると炭素の被覆状態が低くなりすぎた状態であり、化合物の粒子表面の電子伝導性が不十分となり、正極中の電子移動が阻害されるため、電池反応が阻害され十分な放電容量を得ることができない。
比ＩＰＯ４／ＩＧは、上記の観点から、０．０３５≦ＩＰＯ４／ＩＧ≦０．２９であることが好ましく、０．０４≦ＩＰＯ４／ＩＧ≦０．２８５であることがより好ましく、０．０５≦ＩＰＯ４／ＩＧ≦０．２８であることが更に好ましい。
[Raman characteristics]
The potassium-containing positive electrode material of the present embodiment is the ratio IPO4 of the maximum intensity IPO4 of the PO4 band measured at 930 to 1030 cm -1 to the maximum intensity IG of the G band observed at 1550 to 1650 cm -1 by Raman spectroscopy. / IG is 0.03 ≦ IPO4 / IG ≦ 0.3.
The ratio IPO4 / IG is an index showing the carbon coating state of the compound on the particle surface. The carbon coverage of the particle surface of the compound is high, and the more the particle surface is covered with carbon, the smaller the PO4 band derived from the compound particles, while the carbon coverage of the compound particle surface is low and the particle surface is exposed. The larger the PO4 band derived from the compound particles, the larger.
When the ratio IPO4 / IG is less than 0.03, the carbon coating state becomes too high, the contact between the electrolytic solution containing the alkali metal and the crystal surface of the compound is hindered, and the battery reaction is hindered sufficiently. The discharge capacity cannot be obtained. On the other hand, if it exceeds 0.3, the carbon coating state becomes too low, the electron conductivity of the particle surface of the compound becomes insufficient, and the electron transfer in the positive electrode is hindered, so that the battery reaction is hindered. It is not possible to obtain a sufficient discharge capacity.
From the above viewpoint, the ratio IPO4 / IG is preferably 0.035 ≦ IPO4 / IG ≦ 0.29, more preferably 0.04 ≦ IPO4 / IG ≦ 0.285, and more preferably 0.05 ≦. It is more preferable that IPO4 / IG ≦ 0.28.
〔一般式ＫｘＡｙＤｚＰＯ４で表される化合物〕
本実施形態のカリウム含有型正極材料は、一般式ＫｘＡｙＤｚＰＯ４で表される化合物の粒子を含み、一般式ＫｘＡｙＤｚＰＯ４で表される化合物は、正極活物質として機能する。
一般式において、ＡはＣｏ、Ｍｎ、及びＮｉからなる群から選択される少なくとも１種であり、ＤはＭｎ、Ｆｅ、Ｍｇ、Ｃａ、Ｓｒ、Ｂａ、Ｔｉ、Ｚｎ、Ｂ、Ａｌ、Ｇａ、Ｉｎ、Ｓｉ、Ｇｅ、Ｓｃ及びＹからなる群から選択される少なくとも１種であり、ｘ、ｙ、ｚは、０．９＜ｘ＜１．１、０．６５＜ｙ≦１．０、０≦ｚ＜０．３５、０．９＜ｙ＋ｚ＜１．１である。
一般式において、Ａ及びＤは、各々独立に、１種であってもよいし、２種以上であってもよく、例えば、ＫｘＡ１ｙ１Ａ２ｙ２Ｄ１ｚ１Ｄ２ｚ２Ｄ３ｚ３Ｄ４ｚ４ＰＯ４のような式で表されてもよい。このとき、ｙ１とｙ２との合計がｙの範囲、すなわち０．６５を超え１．０以下の範囲にあればよく、ｚ１とｚ２とｚ３とｚ４との合計がｚの範囲、すなわち０以上０．３５未満の範囲にあればよい。
[Compound represented by the general formula KxAyDzPO 4 ]
The potassium-containing positive electrode material of the present embodiment contains particles of a compound represented by the general formula KxAyDzPO 4 , and the compound represented by the general formula KxAyDzPO 4 functions as a positive electrode active material.
In the general formula, A is at least one selected from the group consisting of Co, Mn, and Ni, and D is Mn, Fe, Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In. , Si, Ge, Sc and Y are at least one selected from the group, and x, y, z are 0.9 <x <1.1, 0.65 <y ≦ 1.0, 0 ≦. z <0.35, 0.9 <y + z <1.1.
In the general formula, A and D may be independently one kind or two or more kinds, for example, KxA 1 y 1 A 2 y 2 D 1 z 1 D 2 z 2 D. It may be expressed by an equation such as 3 z 3 D 4 z 4 PO 4 . At this time, the sum of y 1 and y 2 may be in the range of y, that is, in the range of more than 0.65 and 1.0 or less, and the sum of z 1 and z 2 and z 3 and z 4 is z. It may be in the range, that is, in the range of 0 or more and less than 0.35.
一般式ＫｘＡｙＤｚＰＯ４で表される化合物は、上記構成であれば、特に限定されない。
一般式ＫｘＡｙＤｚＰＯ４において、Ａは、Ｃｏ及びＮｉが好ましい。また、Ｄは、はＭｎ、Ｆｅ、Ｍｇ、及びＡｌが好ましく、Ａｌがより好ましい。化合物がこれらの元素を含むことで、高い放電電位、高い安全性を実現可能な正極合材層とすることができる。また、資源量が豊富であるため、選択する材料として好ましい。
The compound represented by the general formula KxAyDzPO 4 is not particularly limited as long as it has the above constitution.
In the general formula KxAyDzPO 4 , A is preferably Co and Ni. Further, as for D, Mn, Fe, Mg, and Al are preferable, and Al is more preferable. When the compound contains these elements, a positive electrode mixture layer capable of achieving high discharge potential and high safety can be obtained. Moreover, since the amount of resources is abundant, it is preferable as a material to be selected.
本実施形態のリン酸塩系化合物の粒子は、一次粒子及び該一次粒子の集合体である二次粒子を含むことが好ましい。
リン酸塩系化合物の一次粒子及び二次粒子を、総じて正極活物質粒子と称する。
The particles of the phosphate-based compound of the present embodiment preferably include primary particles and secondary particles which are aggregates of the primary particles.
The primary particles and secondary particles of the phosphate-based compound are generally referred to as positive electrode active material particles.
〔炭素質被膜〕
本実施形態のカリウム含有型正極材料は、一般式ＫｘＡｙＤｚＰＯ４で表される化合物の粒子（正極活物質粒子）の表面を被覆する炭素質被膜を有する。炭素質被膜を有する正極活物質粒子を炭素質被覆正極活物質粒子とも称する。
[Carbonaceous film]
The potassium-containing positive electrode material of the present embodiment has a carbonaceous film that covers the surface of the particles (positive electrode active material particles) of the compound represented by the general formula KxAyDzPO 4 . Positive electrode active material particles having a carbonaceous film are also referred to as carbonaceous coated positive electrode active material particles.
炭素質被膜は、厚さが０．５ｎｍ以上かつ５ｎｍ以下であることが好ましい。
炭素質被膜の膜厚が０．５ｎｍ以上であることで、炭素質被膜中の電子の移動抵抗の総和が高くなりにくく、アルカリ金属イオン電池の内部抵抗が上昇しにくく、高速充放電レートにおける電圧低下が生じにくい。炭素質被膜の膜厚が５ｎｍ以下であることで、リン酸カリウム化合物にとアルカリ金属を含有する電解液との接触が阻害されにくく、電池反応が進み易く、十分な放電容量を得ることができる。
炭素質被膜の膜厚は、０．６ｎｍ以上であることがより好ましく、４．５ｎｍ以上であることが更に好ましく、０．７ｎｍ以上であることがより更に好ましく、また、４ｎｍ以下であるよりことが好ましく、０．９ｎｍ以下であることが更に好ましく、３．５ｎｍ以下であることがより更に好ましい。
炭素質被膜の膜厚は、正極材料（より具体的には、炭素質被覆正極活物質粒子）上の２０箇所の炭素質被膜の膜厚を、透過型電子顕微鏡を用いて測定し、平均値として算出した値である。
The carbonaceous film preferably has a thickness of 0.5 nm or more and 5 nm or less.
When the film thickness of the carbonaceous film is 0.5 nm or more, the total transfer resistance of electrons in the carbonaceous film is unlikely to increase, the internal resistance of the alkali metal ion battery is unlikely to increase, and the voltage at a high-speed charge / discharge rate is low. It is unlikely to drop. When the thickness of the carbonaceous film is 5 nm or less, the contact between the potassium phosphate compound and the electrolytic solution containing the alkali metal is less likely to be hindered, the battery reaction is easy to proceed, and a sufficient discharge capacity can be obtained. ..
The film thickness of the carbonaceous film is more preferably 0.6 nm or more, further preferably 4.5 nm or more, further preferably 0.7 nm or more, and more preferably 4 nm or less. Is more preferable, and it is more preferably 0.9 nm or less, and even more preferably 3.5 nm or less.
The film thickness of the carbonaceous film is an average value obtained by measuring the film thickness of the carbonaceous film at 20 points on the positive electrode material (more specifically, the carbonaceous coated positive electrode active material particles) using a transmission electron microscope. It is a value calculated as.
炭素質被膜は、該炭素質被膜の原料となる有機物を炭化することにより得られる熱分解炭素質被膜である。
有機物としては、正極活物質粒子の表面に炭素質被膜を形成できる化合物であれば特に限定されず、例えば、ポリビニルアルコール（ＰＶＡ）、ポリビニルピロリドン、セルロース、デンプン、ゼラチン、カルボキシメチルセルロース、メチルセルロース、ヒドロキシメチルセルロース、ヒドロキシエチルセルロース、ポリアクリル酸、ポリスチレンスルホン酸、ポリアクリルアミド、ポリ酢酸ビニル、フェノール、フェノール樹脂、グルコース、フルクトース、ガラクトース、マンノース、マルトース、スクロース、ラクトース、グリコーゲン、ペクチン、アルギン酸、グルコマンナン、キチン、ヒアルロン酸、コンドロイチン、アガロース、ポリエーテル、多価アルコール等が挙げられる。多価アルコールには、たとえば、ポリエチレングリコール、ポリプロピレングリコール、ポリグリセリンおよびグリセリン等が挙げられる。これらは、１種のみを用いてもよく、２種以上を混合して用いてもよい。
The carbonaceous film is a pyrolytic carbonaceous film obtained by carbonizing an organic substance that is a raw material of the carbonaceous film.
The organic substance is not particularly limited as long as it is a compound capable of forming a carbonaceous film on the surface of the positive electrode active material particles, and is, for example, polyvinyl alcohol (PVA), polyvinylpyrrolidone, cellulose, starch, gelatin, carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose. , Hydroxyethyl cellulose, polyacrylic acid, polystyrene sulfonic acid, polyacrylamide, polyvinyl acetate, phenol, phenolic resin, glucose, fructose, galactose, mannose, maltose, sucrose, lactose, glycogen, pectin, alginic acid, glucomannan, chitin, hyaluron Examples thereof include acid, chondroitin, agarose, polyether, polyhydric alcohol and the like. Examples of the polyhydric alcohol include polyethylene glycol, polypropylene glycol, polyglycerin and glycerin. Only one kind of these may be used, or two or more kinds thereof may be mixed and used.
〔比表面積〕
本実施形態におけるカリウム含有型正極材料（好ましくは、炭素質被覆正極活物質粒子）は、比表面積が５ｍ２／ｇ以上かつ３０ｍ２／ｇ以下であることが好ましい。
カリウム含有型正極材料の比表面積が５ｍ２／ｇ以上であることで、化合物の一次粒子の粒径が細かくなり、カリウムイオン及び電子の移動にかかる時間を短くして大電流での作動時及び低温での作動時の容量を増加することができる。
カリウム含有型正極材料の比表面積が３０ｍ２／ｇ以下であることで、金属溶出を抑制することができる。
エネルギー密度をより高める観点から、カリウム含有型正極材料の比表面積は、７ｍ２／ｇ以上かつ２４ｍ２／ｇ以下であることがより好ましく、８ｍ２／ｇ以上かつ２０ｍ２／ｇ以下であることが更に好ましい。
上記比表面積は、比表面積計（例えば、日本ベル社製、商品名：ＢＥＬＳＯＲＰ－ｍｉｎｉ）を用いて、窒素（Ｎ２）吸着によるＢＥＴ法により測定することができる。
〔Specific surface area〕
The potassium-containing positive electrode material (preferably carbonaceous coated positive electrode active material particles) in the present embodiment preferably has a specific surface area of 5 m 2 / g or more and 30 m 2 / g or less.
When the specific surface area of the potassium-containing positive electrode material is 5 m 2 / g or more, the particle size of the primary particles of the compound becomes finer, the time required for the movement of potassium ions and electrons is shortened, and when operating at a large current and The capacity when operating at low temperature can be increased.
When the specific surface area of the potassium-containing positive electrode material is 30 m 2 / g or less, metal elution can be suppressed.
From the viewpoint of further increasing the energy density, the specific surface area of the potassium-containing positive electrode material is more preferably 7 m 2 / g or more and 24 m 2 / g or less, and 8 m 2 / g or more and 20 m 2 / g or less. Is more preferable.
The specific surface area can be measured by a BET method by adsorbing nitrogen (N 2 ) using a specific surface area meter (for example, manufactured by Nippon Bell Co., Ltd., trade name: BELSORP-mini).
（炭素量）
本実施形態におけるカリウム含有型正極材料（好ましくは、炭素質被覆正極活物質粒子）は、炭素量が１．０質量％以上かつ４．０質量％以下であることが好ましい。
カリウム含有型正極材料の炭素量が１．０質量％以上であることで、炭素間の距離が縮まり、導電パスが容易になり易いため、アルカリ金属イオン電池のサイクル特性を向上し易い。また、カリウム含有型正極材料の炭素量が４．０質量％以下であることで、オリビン型リン酸塩系化合物の一次粒子間の空隙が狭まりにくく、カリウム含有型正極材料の電解液保持量を高めることができ、入力特性を向上し易い。
エネルギー密度をより高くする観点から、カリウム含有型正極材料の炭素量は、１．２質量％以上かつ３．５質量％以下であることがより好ましく、１．４質量％以上かつ３．０質量％以下であることが更に好ましい。
なお、上記炭素含有量は、炭素分析計（例えば、堀場製作所社製、型番：ＥＭＩＡ－２２０Ｖ）を用いて測定することができる。
(Carbon content)
The potassium-containing positive electrode material (preferably carbonaceous coated positive electrode active material particles) in the present embodiment preferably has a carbon content of 1.0% by mass or more and 4.0% by mass or less.
When the carbon content of the potassium-containing positive electrode material is 1.0% by mass or more, the distance between carbons is shortened and the conductive path is easily facilitated, so that the cycle characteristics of the alkali metal ion battery are easily improved. Further, since the carbon content of the potassium-containing positive electrode material is 4.0% by mass or less, the voids between the primary particles of the olivine-type phosphate compound are less likely to be narrowed, and the amount of the electrolytic solution retained in the potassium-containing positive electrode material can be increased. It can be enhanced and the input characteristics can be easily improved.
From the viewpoint of increasing the energy density, the carbon content of the potassium-containing positive electrode material is more preferably 1.2% by mass or more and 3.5% by mass or less, and 1.4% by mass or more and 3.0% by mass or less. % Or less is more preferable.
The carbon content can be measured using a carbon analyzer (for example, manufactured by HORIBA, Ltd., model number: EMIA-220V).
本実施形態におけるカリウム含有型正極材料（好ましくは、炭素質被覆正極活物質粒子）のタップ密度は、１．０～１．６ｇ／ｃｍ３であることが好ましい。
カリウム含有型正極材料のタップ密度が１．０ｇ／ｃｍ３以上であることで、正極活物質と電解液との接触面積が大きくなり過ぎず、正極活物質からの金属溶出量を抑制することができる。カリウム含有型正極材料のタップ密度が１．６ｇ／ｃｍ３以下であることで、正極活物質と電解液との接触面積が大きくなり、正極活物質へのカリウムイオンの脱挿入がしやすくなり、容量を大きくすることができる。
上記観点から、カリウム含有型正極材料のタップ密度は、１．１～１．５であることがより好ましく、１．２～１．５であることが更に好ましい。
タップ密度は、ＪＩＳ Ｒ １６２８：１９９７ ファインセラミックス粉末のかさ密度測定方法に則った手法にて測定することができる。
The tap density of the potassium-containing positive electrode material (preferably carbonaceous coated positive electrode active material particles) in the present embodiment is preferably 1.0 to 1.6 g / cm 3 .
When the tap density of the potassium-containing positive electrode material is 1.0 g / cm 3 or more, the contact area between the positive electrode active material and the electrolytic solution does not become too large, and the amount of metal elution from the positive electrode active material can be suppressed. can. When the tap density of the potassium-containing positive electrode material is 1.6 g / cm 3 or less, the contact area between the positive electrode active material and the electrolytic solution becomes large, and it becomes easy to remove and insert potassium ions into the positive electrode active material. The capacity can be increased.
From the above viewpoint, the tap density of the potassium-containing positive electrode material is more preferably 1.1 to 1.5, and further preferably 1.2 to 1.5.
The tap density can be measured by a method according to the bulk density measuring method of JIS R 1628: 1997 fine ceramic powder.
炭素質被膜で被覆された正極活物質粒子（炭素質被覆正極活物質粒子）の一次粒子の平均粒子径は、好ましくは５０ｎｍ以上、より好ましくは７０ｎｍ以上、さらに好ましくは１００ｎｍ以上であり、そして、好ましくは５００ｎｍ以下、より好ましくは４５０ｎｍ以下、さらに好ましくは４００ｎｍ以下である。一次粒子の平均粒子径が５０ｎｍ以上であるとカリウム含有型正極材料の比表面積の増加に起因する炭素量の増加を抑制でき、これによりアルカリ金属イオン電池の充放電容量が低減することを抑制できる。一方、５００ｎｍ以下であるとカリウム含有型正極材料内を移動するカリウムイオンの移動時間または電子の移動時間を短くすることができる。これにより、アルカリ金属イオン電池の内部抵抗の増加に起因する出力特性の悪化を抑制できる。
ここで、一次粒子の平均粒子径とは、個数平均粒子径のことである。上記一次粒子の平均粒子径は、走査電子顕微鏡（ＳＥＭ）観察により測定した２００個以上の粒子の粒子径を個数平均することで求めることができる。
The average particle size of the primary particles of the positive electrode active material particles coated with the carbonaceous film (carbonaceous coated positive electrode active material particles) is preferably 50 nm or more, more preferably 70 nm or more, still more preferably 100 nm or more, and It is preferably 500 nm or less, more preferably 450 nm or less, still more preferably 400 nm or less. When the average particle size of the primary particles is 50 nm or more, it is possible to suppress an increase in the amount of carbon due to an increase in the specific surface area of the potassium-containing positive electrode material, thereby suppressing a decrease in the charge / discharge capacity of the alkali metal ion battery. .. On the other hand, when it is 500 nm or less, the movement time of potassium ions or the movement time of electrons in the potassium-containing positive electrode material can be shortened. As a result, deterioration of output characteristics due to an increase in the internal resistance of the alkali metal ion battery can be suppressed.
Here, the average particle size of the primary particles is the number average particle size. The average particle size of the primary particles can be obtained by averaging the particle sizes of 200 or more particles measured by scanning electron microscope (SEM) observation.
炭素質被覆正極活物質粒子の二次粒子の平均粒子径は、好ましくは０．５μｍ以上、より好ましくは１．０μｍ以上、さらに好ましくは１．５μｍ以上であり、そして、好ましくは２０μｍ以下、より好ましくは１８μｍ以下、さらに好ましくは１５μｍ以下である。二次粒子の平均粒子径が０．５μｍ以上であるとカリウム含有型正極材料と導電助剤とバインダー樹脂（結着剤）と溶剤とを混合してアルカリ金属イオン電池正極材料ペーストを調製する際、導電助剤及び結着剤が多量に必要となることを抑制できる。これによりアルカリ金属イオン電池の正極の正極合材層における単位質量あたりのアルカリ金属イオン電池の電池容量を高くすることができる。一方、２０μｍ以下であるとアルカリ金属イオン電池の正極の正極合材層中の導電助剤や結着剤の分散性及び均一性を高くすることができる。その結果、アルカリ金属イオン電池の高速充放電における放電容量が高くなる。
ここで、二次粒子の平均粒子径とは、体積平均粒子径のことである。上記二次粒子の平均粒子径は、レーザー回折散乱式粒度分布測定装置等を用いて測定することができる。
The average particle size of the secondary particles of the carbonaceous coated positive electrode active material particles is preferably 0.5 μm or more, more preferably 1.0 μm or more, still more preferably 1.5 μm or more, and preferably 20 μm or less. It is preferably 18 μm or less, more preferably 15 μm or less. When the average particle size of the secondary particles is 0.5 μm or more, when preparing an alkali metal ion battery positive electrode material paste by mixing a potassium-containing positive electrode material, a conductive auxiliary agent, a binder resin (binding agent), and a solvent. , It is possible to suppress the need for a large amount of conductive auxiliary agent and binder. As a result, the battery capacity of the alkali metal ion battery per unit mass in the positive electrode mixture layer of the positive electrode of the alkali metal ion battery can be increased. On the other hand, when it is 20 μm or less, the dispersibility and uniformity of the conductive auxiliary agent and the binder in the positive electrode mixture layer of the positive electrode of the alkali metal ion battery can be improved. As a result, the discharge capacity of the alkali metal ion battery in high-speed charging / discharging becomes high.
Here, the average particle size of the secondary particles is the volume average particle size. The average particle size of the secondary particles can be measured by using a laser diffraction / scattering type particle size distribution measuring device or the like.
正極活物質粒子に対する炭素質被膜の被覆率は６０％以上であることが好ましく、８０％以上であることがより好ましい。炭素質被膜の被覆率が６０％以上であることで、炭素質被膜の被覆効果が十分に得られる。
なお、炭素質被膜の被覆率は、透過型電子顕微鏡（ＴＥＭ）、エネルギー分散型Ｘ線分析装置（Ｅｎｅｒｇｙ Ｄｉｓｐｅｒｓｉｖｅ Ｘ－ｒａｙ ｍｉｃｒｏａｎａｌｙｚｅｒ、ＥＤＸ）等を用いて粒子を観察し、粒子表面を覆っている部分の割合を算出し、その平均値から求めることができる。
The coverage of the carbonaceous film on the positive electrode active material particles is preferably 60% or more, more preferably 80% or more. When the coverage of the carbonaceous film is 60% or more, the coating effect of the carbonaceous film can be sufficiently obtained.
The coverage of the carbonaceous film is determined by observing the particles using a transmission electron microscope (TEM), an energy dispersive X-ray analyzer (EDX), etc., and covering the particle surface. The ratio of parts can be calculated and calculated from the average value.
炭素質被膜を構成する炭素分によって計算される、炭素質被膜の密度は、好ましくは０．３ｇ／ｃｍ３以上、より好ましくは０．４ｇ／ｃｍ３以上であり、そして、好ましくは２．０ｇ／ｃｍ３以下、より好ましくは１．８ｇ／ｃｍ３以下である。炭素質被膜を構成する炭素分によって計算される、炭素質被膜の密度とは、炭素質被膜が炭素のみから構成されると想定した場合に、炭素質被膜の単位体積当たりの質量である。
炭素質被膜の密度が０．３ｇ／ｃｍ３以上であると、炭素質被膜が十分な電子伝導性を示すことができる。一方、２．０ｇ／ｃｍ３以下であると、炭素質被膜中に層状構造からなる黒鉛の微結晶が少量であるため、カリウムイオンが炭素質被膜中を拡散する際に黒鉛の微結晶による立体障害が生じない。これにより、カリウムイオン移動抵抗が高くなることがない。その結果、アルカリ金属イオン電池の内部抵抗が上昇することがなく、アルカリ金属イオン電池の高速充放電レートにおける電圧低下が生じない。
The density of the carbonaceous film, calculated by the carbon content constituting the carbonaceous film, is preferably 0.3 g / cm 3 or more, more preferably 0.4 g / cm 3 or more, and preferably 2.0 g. It is / cm 3 or less, more preferably 1.8 g / cm 3 or less. The density of the carbonaceous film, calculated by the carbon content constituting the carbonaceous film, is the mass per unit volume of the carbonaceous film, assuming that the carbonaceous film is composed only of carbon.
When the density of the carbonaceous film is 0.3 g / cm 3 or more, the carbonaceous film can exhibit sufficient electron conductivity. On the other hand, when it is 2.0 g / cm 3 or less, since the amount of graphite microcrystals having a layered structure is small in the carbonaceous film, steric hindrance due to graphite microcrystals when potassium ions diffuse in the carbonaceous film. No obstacles occur. As a result, the potassium ion transfer resistance does not increase. As a result, the internal resistance of the alkali metal ion battery does not increase, and the voltage does not decrease at the high-speed charge / discharge rate of the alkali metal ion battery.
（アルカリ金属イオン電池正極材料の製造方法）
本実施形態のアルカリ金属イオン電池正極材料の製造方法は、特に限定されないが、例えば、正極活物質粒子を得る工程（Ａ）と、前記工程（Ａ）で得られた正極活物質粒子に有機化合物を添加して混合物を調製する工程（Ｂ）と、混合物を焼成鞘に入れて焼成する工程（Ｃ）とを有する。
(Manufacturing method of alkali metal ion battery positive electrode material)
The method for producing the positive electrode material of the alkali metal ion battery of the present embodiment is not particularly limited, but for example, the step (A) for obtaining the positive electrode active material particles and the organic compound in the positive electrode active material particles obtained in the step (A). It has a step (B) of preparing a mixture by adding the mixture, and a step (C) of putting the mixture in a firing sheath and firing it.
〔工程（Ａ）〕
工程（Ａ）において、上記正極活物質粒子を製造する方法としては、特に限定されず、例えば、固相法、液相法、気相法等の従来の方法を用いることができる。このような方法で得られた粒子状のＫｘＡｙＤｚＰＯ４を以下、「ＫｘＡｙＤｚＰＯ４粒子」と言う。
ＫｘＡｙＤｚＰＯ４粒子は、例えば、Ｋ源と、Ａ源と、Ｐ源と、水と、必要に応じてＤ源と、を混合して得られるスラリー状の混合物を水熱合成して前駆体となるＫｘＡｙＤｚＰＯ４・Ｈ２Ｏを得た後に、前駆体を加熱処理することで目的のＫｘＡｙＤｚＰＯ４粒子を得られる。水熱合成によれば、ＫｘＡｙＤｚＰＯ４・Ｈ２Ｏ前駆体は、水中に沈殿物として生成する。
この水熱合成には耐圧密閉容器を用いることが好ましい。
[Step (A)]
In the step (A), the method for producing the positive electrode active material particles is not particularly limited, and for example, conventional methods such as a solid phase method, a liquid phase method, and a gas phase method can be used. The particulate KxAyDzPO 4 obtained by such a method is hereinafter referred to as "KxAyDzPO 4 particles".
The KxAyDzPO 4 particles are, for example, hydrothermally synthesized into a precursor by hydrothermally synthesizing a slurry-like mixture obtained by mixing a K source, an A source, a P source, water, and if necessary, a D source. After obtaining KxAyDzPO 4 · H 2 O, the precursor is heat-treated to obtain the desired KxAyDzPO 4 particles. According to hydrothermal synthesis, the KxAyDzPO 4 · H2O precursor is formed as a precipitate in water.
It is preferable to use a pressure-resistant airtight container for this hydrothermal synthesis.
水熱合成の反応条件としては、例えば、加熱温度は、好ましくは１１０℃以上３００℃以下、より好ましくは１１５℃以上２８０℃以下、さらに好ましくは１２０℃以上２７０℃以下である。加熱温度を上記範囲内とすることで、正極活物質粒子の比表面積を上述の範囲内とすることができる。
また、反応時間は、好ましくは２０分以上１６９時間以下、より好ましくは３０分以上２４時間以下、さらに好ましくは１時間以上１０時間以下である。さらに、反応時の圧力は、好ましくは０．１ＭＰａ以上２２ＭＰａ以下、より好ましくは０．１ＭＰａ以上１７ＭＰａ以下である。
As the reaction conditions for hydrothermal synthesis, for example, the heating temperature is preferably 110 ° C. or higher and 300 ° C. or lower, more preferably 115 ° C. or higher and 280 ° C. or lower, and further preferably 120 ° C. or higher and 270 ° C. or lower. By setting the heating temperature within the above range, the specific surface area of the positive electrode active material particles can be within the above range.
The reaction time is preferably 20 minutes or more and 169 hours or less, more preferably 30 minutes or more and 24 hours or less, and further preferably 1 hour or more and 10 hours or less. Further, the pressure during the reaction is preferably 0.1 MPa or more and 22 MPa or less, and more preferably 0.1 MPa or more and 17 MPa or less.
Ｋ源、Ａ源、Ｄ源及びＰ源のモル比（Ｋ：Ａ：Ｄ：Ｐ）は、好ましくは２．５～４．０：０．５～１．０：０～１．０：０．９～１．１５、より好ましくは２．８～３．５：０．６～１．０：０～１．０：０．９５～１．１である。 The molar ratio (K: A: D: P) of K source, A source, D source and P source is preferably 2.5 to 4.0: 0.5 to 1.0: 0 to 1.0: 0. It is 9.9 to 1.15, more preferably 2.8 to 3.5: 0.6 to 1.0: 0 to 1.0: 0.95 to 1.1.
ここで、Ｋ源としては、例えば、水酸化カリウム（ＫＯＨ）等の水酸化物；炭酸カリウム（Ｋ２ＣＯ３）、塩化カリウム（ＫＣｌ）、硝酸カリウム（ＫＮＯ３）、リン酸カリウム（Ｋ３ＰＯ４）、リン酸水素二カリウム（Ｋ２ＨＰＯ４）およびリン酸二水素カリウム（ＫＨ２ＰＯ４）等のカリウム無機酸塩；酢酸カリウム（ＫＣＨ３ＣＯＯ）、蓚酸カリウム（（ＣＯＯＫ）２）等のカリウム有機酸塩；ならびに、これらの水和物からなる群から選択される少なくとも１種を用いることが好ましい。
なお、リン酸カリウム（Ｋ３ＰＯ４）は、Ｋ源およびＰ源としても用いることができる。
Here, as the K source, for example, a hydroxide such as potassium hydroxide (KOH); potassium carbonate (K 2 CO 3 ), potassium chloride (KCl), potassium nitrate (KNO 3 ), potassium phosphate (K 3 PO). 4 ), Potassium inorganic acid salts such as dipotassium hydrogen phosphate (K 2 HPO 4 ) and potassium dihydrogen phosphate (KH 2 PO 4 ); potassium acetate (KCH 3 COO), potassium oxalate ((COOK) 2 ), etc. Potassium organic acid salt; and at least one selected from the group consisting of these hydrates is preferably used.
In addition, potassium phosphate (K 3 PO 4 ) can also be used as a K source and a P source.
Ａ源としては、Ｃｏ、Ｍｎ、及びＮｉからなる群から選択される少なくとも１種を含む塩化物、カルボン酸塩、硫酸塩等が挙げられる。例えば、ＫｘＡｙＤｚＰＯ４におけるＡがＮｉである場合、Ｎｉ源としては、塩化ニッケル（ＮｉＣｌ２）、硫酸ニッケル（ＮｉＳＯ４）、及びこれらの水和物等；ＡがＣｏである場合、Ｃｏ源としては、塩化コバルト（ＣｏＣｌ２）、硫酸コバルト（ＣｏＳＯ４）、及びこれらの水和物等が挙げられる。 Examples of the A source include chlorides, carboxylates, sulfates and the like containing at least one selected from the group consisting of Co, Mn and Ni. For example, when A in KxAyDzPO 4 is Ni, the Ni source is nickel chloride (NiCl 2 ), nickel sulfate (NiSO 4 ), and hydrates thereof, etc .; when A is Co, the Co source is , Cobalt chloride (CoCl 2 ), cobalt sulfate (CoSO 4 ), and hydrates thereof.
Ｄ源としては、Ｍｎ、Ｆｅ、Ｍｇ、Ｃａ、Ｓｒ、Ｂａ、Ｔｉ、Ｚｎ、Ｂ、Ａｌ、Ｇａ、Ｉｎ、Ｓｉ、Ｇｅ、Ｓｃ及びＹからなる群から選択される少なくとも１種を含む塩化物、カルボン酸塩、硫酸塩等が挙げられる。例えば、ＫｘＡｙＤｚＰＯ４におけるＤがＡｌである場合、Ａｌ源としては、水酸化アルミニウム（Ａｌ（ＯＨ）３）、塩化アルミニウム（ＡｌＣｌ３）、硫酸アルミニウム（Ａｌ２（ＳＯ４）３）、硝酸アルミニウム（Ａｌ（ＮＯ３）３）、酢酸アルミニウム（Ａｌ（ＣＨ３ＣＯＯ）３）、及びこれらの水和物等が挙げられる。 As the D source, a chloride containing at least one selected from the group consisting of Mn, Fe, Mg, Ca, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc and Y. , Carboxylate, sulfate and the like. For example, when D in KxAyDzPO 4 is Al, the Al sources include aluminum hydroxide (Al (OH) 3 ), aluminum chloride (AlCl 3 ), aluminum sulfate (Al 2 (SO 4 ) 3 ), and aluminum nitrate (Al 2 (SO 4) 3). Examples thereof include Al (NO 3 ) 3 ), aluminum acetate (Al (CH 3 COO) 3 ), and hydrates thereof.
Ｐ源としては、リン酸（Ｈ３ＰＯ４）、リン酸二水素アンモニウム（ＮＨ４Ｈ２ＰＯ４）、リン酸水素二アンモニウム（（ＮＨ４）２ＨＰＯ４）等のリン酸化合物が挙げられる。これらの中でも、Ｐ源としては、リン酸、リン酸二水素アンモニウム及びリン酸水素二アンモニウムからなる群から選択される少なくとも１種を用いることが好ましい。 Examples of the P source include phosphoric acid compounds such as phosphoric acid (H 3 PO 4 ), ammonium dihydrogen phosphate (NH 4 H 2 PO 4 ), and diammonium hydrogen phosphate ((NH 4 ) 2 HPO 4 ). .. Among these, as the P source, it is preferable to use at least one selected from the group consisting of phosphoric acid, ammonium dihydrogen phosphate and diammonium hydrogen phosphate.
〔工程（Ｂ）〕
工程（Ｂ）では、前記工程（Ａ）で得られた正極活物質粒子（ＫｘＡｙＤｚＰＯ４粒子）に有機化合物を添加して混合物を調製する。
まず、上記正極活物質粒子に有機化合物を添加し、次いで、溶媒を添加する。
正極活物質粒子に対する有機化合物の配合量は、炭素質被膜の膜厚を０．５ｎｍ以上かつ５ｎｍ以下とする観点から、有機化合物の全質量を炭素元素に換算したとき、正極活物質粒子１００質量部に対して、好ましくは０．１５質量部以上３質量部以下、より好ましくは０．３質量部以上２質量部以下である。
また、正極活物質粒子に対する有機化合物の配合量が０．１５質量部以上であると、この有機化合物を熱処理することにより生じる炭素質被膜の正極活物質粒子表面における被覆率を８０％以上にすることができる。これにより、アルカリ金属イオン電池の高入力特性及びサイクル特性を向上することができる。一方、正極活物質粒子に対する有機化合物の配合量が３質量部以下であると、正極活物質粒子の嵩密度を小さくし、電極密度の低下を抑制し、単位体積あたりのアルカリ金属イオン電池の容量低下を抑制することができる。
[Step (B)]
In the step (B), an organic compound is added to the positive electrode active material particles (KxAyDzPO 4 particles) obtained in the step (A) to prepare a mixture.
First, an organic compound is added to the positive electrode active material particles, and then a solvent is added.
The blending amount of the organic compound with respect to the positive electrode active material particles is 100 mass of the positive electrode active material particles when the total mass of the organic compound is converted into a carbon element from the viewpoint that the film thickness of the carbonaceous film is 0.5 nm or more and 5 nm or less. It is preferably 0.15 parts by mass or more and 3 parts by mass or less, and more preferably 0.3 parts by mass or more and 2 parts by mass or less.
Further, when the blending amount of the organic compound with respect to the positive electrode active material particles is 0.15 parts by mass or more, the coverage of the carbonaceous film formed by heat treatment of the organic compound on the surface of the positive electrode active material particles is increased to 80% or more. be able to. This makes it possible to improve the high input characteristics and cycle characteristics of the alkali metal ion battery. On the other hand, when the blending amount of the organic compound with respect to the positive electrode active material particles is 3 parts by mass or less, the bulk density of the positive electrode active material particles is reduced, the decrease in the electrode density is suppressed, and the capacity of the alkali metal ion battery per unit volume. The decrease can be suppressed.
正極活物質粒子に溶媒を添加する際、その固形分が好ましくは１０～６０質量％、より好ましくは１５～５５質量％、さらに好ましくは２５～５０質量％となるように調整する。固形分を上記範囲内とすることで、得られるカリウム含有型正極材料のタップ密度を上述の範囲内とすることができる。 When the solvent is added to the positive electrode active material particles, the solid content thereof is adjusted to preferably 10 to 60% by mass, more preferably 15 to 55% by mass, and further preferably 25 to 50% by mass. By setting the solid content within the above range, the tap density of the obtained potassium-containing positive electrode material can be within the above range.
上記溶媒としては、たとえば、水；メタノール、エタノール、１－プロパノール、２－プロパノール（イソプロピルアルコール：ＩＰＡ）、ブタノール、ペンタノール、ヘキサノール、オクタノールおよびジアセトンアルコール等のアルコール類、酢酸エチル、酢酸ブチル、乳酸エチル、プロピレングリコールモノメチルエーテルアセテート、プロピレングリコールモノエチルエーテルアセテートおよびγ－ブチロラクトン等のエステル類；ジエチルエーテル、エチレングルコールモノメチルエーテル（メチルセロソルブ）、エチレングルコールモノエチルエーテル（エチルセロソルブ）、エチレングルコールモノブチルエーテル（ブチルセロソルブ）、ジエチレングリコールモノメチルエーテルおよびジエチレングリコールモノエチルエーテル等のエーテル類；アセトン、メチルエチルケトン（ＭＥＫ）、メチルイソブチルケトン（ＭＩＢＫ）、アセチルアセトンおよびシクロヘキサノン等のケトン類；ジメチルホルムアミド、Ｎ，Ｎ－ジメチルアセトアセトアミドおよびＮ－メチルピロリドン等のアミド類；ならびにエチレングリコール、ジエチレングリコールおよびプロピレングリコール等のグリコール類等が挙げられる。これらの溶媒は、１種を用いてもよく、２種以上を混合して用いてもよい。これらの溶媒の中で、好ましい溶媒は水である。
なお、必要に応じて分散剤を添加してもよい。
Examples of the solvent include water; alcohols such as methanol, ethanol, 1-propanol, 2-propanol (isopropyl alcohol: IPA), butanol, pentanol, hexanol, octanol and diacetone alcohol, ethyl acetate, butyl acetate, and the like. Esters such as ethyl lactate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate and γ-butyrolactone; diethyl ether, ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), ethylene glue Ethers such as colmonobutyl ether (butyl cellosolve), diethylene glycol monomethyl ether and diethylene glycol monoethyl ether; ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), acetyl acetone and cyclohexanone; dimethylformamide, N, N-dimethyl Examples include amides such as acetoacetamide and N-methylpyrrolidone; and glycols such as ethylene glycol, diethylene glycol and propylene glycol. One of these solvents may be used, or two or more of these solvents may be mixed and used. Of these solvents, the preferred solvent is water.
A dispersant may be added as needed.
正極活物質粒子と有機化合物とを、溶媒に分散させる方法としては、正極活物質粒子が均一に分散し、かつ有機化合物が溶解または分散する方法であれば、とくに限定されない。このような分散に使用する装置としては、たとえば、遊星ボールミル、振動ボールミル、ビーズミル、ペイントシェーカー、アトライタ等の媒体粒子を高速で撹拌する媒体撹拌型分散装置が挙げられる。 The method for dispersing the positive electrode active material particles and the organic compound in the solvent is not particularly limited as long as the positive electrode active material particles are uniformly dispersed and the organic compound is dissolved or dispersed. Examples of the device used for such dispersion include a medium stirring type dispersion device for stirring medium particles such as a planetary ball mill, a vibrating ball mill, a bead mill, a paint shaker, and an attritor at high speed.
噴霧熱分解法を用いて、上記混合物を高温雰囲気中、たとえば、１１０℃以上２００℃以下の大気中に噴霧し、乾燥して、混合物の造粒体を生成してもよい。
この噴霧熱分解法では、速やかに乾燥して略球状の造粒体を生成するためには、噴霧の際の液滴の粒子径は、０．０１μｍ以上１００μｍ以下であることが好ましい。
The mixture may be sprayed into a high temperature atmosphere, for example, 110 ° C. or higher and 200 ° C. or lower, and dried to form a granulated product of the mixture by using a spray pyrolysis method.
In this spray pyrolysis method, the particle size of the droplets at the time of spraying is preferably 0.01 μm or more and 100 μm or less in order to quickly dry to form a substantially spherical granule.
〔工程（Ｃ）〕
工程（Ｃ）では、前記工程（Ｂ）で得られた混合物を焼成鞘に入れて焼成する。
焼成鞘として、たとえば、カーボン等の熱伝導性に優れる物質からなる焼成鞘が好適に用いられる。
焼成温度は、好ましくは６３０℃以上７９０℃以下であり、より好ましくは６８０℃以上７７０℃以下ある。
焼成温度が６３０℃以上であると、有機化合物の分解及び反応が十分に進行し、有機化合物を十分に炭化させることができる。その結果、得られたカリウム含有型正極材料に低抵抗の炭素質被膜を形成することができる。一方、焼成温度が７９０℃以下であると、カリウム含有型正極材料の粒成長が進行せず十分に高い比表面積を保つことができる。その結果、アルカリ金属イオン電池を形成した場合に高速充放電レートにおける放電容量が大きくなり、十分な充放電レート性能を実現することができる。
[Step (C)]
In the step (C), the mixture obtained in the step (B) is placed in a firing sheath and fired.
As the firing sheath, for example, a firing sheath made of a substance having excellent thermal conductivity such as carbon is preferably used.
The firing temperature is preferably 630 ° C. or higher and 790 ° C. or lower, and more preferably 680 ° C. or higher and 770 ° C. or lower.
When the calcination temperature is 630 ° C. or higher, the decomposition and reaction of the organic compound proceed sufficiently, and the organic compound can be sufficiently carbonized. As a result, a carbonaceous film having low resistance can be formed on the obtained potassium-containing positive electrode material. On the other hand, when the firing temperature is 790 ° C. or lower, the grain growth of the potassium-containing positive electrode material does not proceed and a sufficiently high specific surface area can be maintained. As a result, when the alkali metal ion battery is formed, the discharge capacity at a high-speed charge / discharge rate becomes large, and sufficient charge / discharge rate performance can be realized.
焼成時間は、有機化合物が十分に炭化する時間であればよく、とくに制限はないが、たとえば、０．１時間以上１００時間以下である。
焼成雰囲気は、好ましくは窒素（Ｎ２）およびアルゴン（Ａｒ）等の不活性ガスからなる不活性雰囲気または水素（Ｈ２）等の還元性ガスを含む還元性雰囲気である。混合物の酸化をより抑えたい場合には、焼成雰囲気は還元性雰囲気であることがより好ましい。
The firing time may be any time as long as the organic compound is sufficiently carbonized, and is not particularly limited, but is, for example, 0.1 hour or more and 100 hours or less.
The firing atmosphere is preferably an inert atmosphere composed of an inert gas such as nitrogen (N 2 ) and argon (Ar) or a reducing atmosphere containing a reducing gas such as hydrogen (H 2 ). When it is desired to further suppress the oxidation of the mixture, it is more preferable that the firing atmosphere is a reducing atmosphere.
工程（Ｃ）の焼成により、有機化合物は焼成により分解および反応して、炭素が生成する。そして、この炭素は正極活物質粒子の表面に付着して炭素質被膜となる。これにより、正極活物質粒子の表面は炭素質被膜により覆われる。 By the calcination in the step (C), the organic compound is decomposed and reacted by the calcination to produce carbon. Then, this carbon adheres to the surface of the positive electrode active material particles to form a carbonaceous film. As a result, the surface of the positive electrode active material particles is covered with the carbonaceous film.
＜アルカリ金属イオン電池＞
本実施形態のアルカリ金属イオン電池は、本実施形態のアルカリ金属イオン電池用正極材料を用いた正極と、Ｌｉイオン、Ｎａイオン、及びＫイオンからなる群から選択される少なくとも１種を含む電解質とを有する。
<Alkali metal ion battery>
The alkali metal ion battery of the present embodiment includes a positive electrode using the positive electrode material for an alkali metal ion battery of the present embodiment, and an electrolyte containing at least one selected from the group consisting of Li ion, Na ion, and K ion. Have.
〔正極〕
正極を作製するには、上記のカリウム含有型正極材料と、バインダー樹脂からなる結着剤と、溶媒とを混合して、正極形成用塗料又は正極形成用ペーストを調製する。この際、必要に応じてカーボンブラック、アセチレンブラック、グラファイト、ケッチェンブラック、天然黒鉛、人造黒鉛等の導電助剤を添加してもよい。
結着剤、すなわちバインダー樹脂としては、例えば、ポリテトラフルオロエチレン（ＰＴＦＥ）樹脂、ポリフッ化ビニリデン（ＰＶｄＦ）樹脂、フッ素ゴム等が好適に用いられる。
カリウム含有型正極材料とバインダー樹脂との配合比は、特に限定されないが、例えば、カリウム含有型正極材料１００質量部に対してバインダー樹脂を１質量部～３０質量部、好ましくは３質量部～２０質量部とする。
[Positive electrode]
In order to prepare a positive electrode, the above-mentioned potassium-containing positive electrode material, a binder made of a binder resin, and a solvent are mixed to prepare a positive electrode forming paint or a positive electrode forming paste. At this time, if necessary, a conductive auxiliary agent such as carbon black, acetylene black, graphite, Ketjen black, natural graphite, or artificial graphite may be added.
As the binder, that is, the binder resin, for example, polytetrafluoroethylene (PTFE) resin, polyvinylidene fluoride (PVdF) resin, fluororubber and the like are preferably used.
The blending ratio of the potassium-containing positive electrode material and the binder resin is not particularly limited, but for example, 1 part by mass to 30 parts by mass, preferably 3 parts by mass to 20 parts by mass of the binder resin with respect to 100 parts by mass of the potassium-containing positive positive material. It is a mass part.
正極形成用塗料又は正極形成用ペーストに用いる溶媒としては、バインダー樹脂の性質に合わせて適宜選択すればよい。
例えば、水、メタノール、エタノール、１－プロパノール、２－プロパノール（イソプロピルアルコール：ＩＰＡ）、ブタノール、ペンタノール、ヘキサノール、オクタノール、ジアセトンアルコール等のアルコール類、酢酸エチル、酢酸ブチル、乳酸エチル、プロピレングリコールモノメチルエーテルアセテート、プロピレングリコールモノエチルエーテルアセテート、γ－ブチロラクトン等のエステル類、ジエチルエーテル、エチレングルコールモノメチルエーテル（メチルセロソルブ）、エチレングルコールモノエチルエーテル（エチルセロソルブ）、エチレングルコールモノブチルエーテル（ブチルセロソルブ）、ジエチレングリコールモノメチルエーテル、ジエチレングリコールモノエチルエーテル等のエーテル類、アセトン、メチルエチルケトン（ＭＥＫ）、メチルイソブチルケトン（ＭＩＢＫ）、アセチルアセトン、シクロヘキサノン等のケトン類、ジメチルホルムアミド、Ｎ，Ｎ－ジメチルアセトアセトアミド、Ｎ－メチルピロリドン等のアミド類、エチレングリコール、ジエチレングリコール、プロピレングリコール等のグリコール類等を挙げることができる。これらは、１種のみを用いてもよく、２種以上を混合して用いてもよい。
The solvent used for the positive electrode forming paint or the positive electrode forming paste may be appropriately selected according to the properties of the binder resin.
For example, alcohols such as water, methanol, ethanol, 1-propanol, 2-propanol (isopropyl alcohol: IPA), butanol, pentanol, hexanol, octanol, diacetone alcohol, ethyl acetate, butyl acetate, ethyl lactate, propylene glycol. Esters such as monomethyl ether acetate, propylene glycol monoethyl ether acetate, γ-butyrolactone, diethyl ether, ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), ethylene glycol monobutyl ether (butyl cellosolve) ), Ethers such as diethylene glycol monomethyl ether and diethylene glycol monoethyl ether, ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), acetyl acetone and cyclohexanone, dimethylformamide, N, N-dimethylacetoacetamide, N- Examples thereof include amides such as methylpyrrolidone, glycols such as ethylene glycol, diethylene glycol and propylene glycol. Only one kind of these may be used, or two or more kinds thereof may be mixed and used.
次いで、正極形成用塗料又は正極形成用ペーストを、アルミニウム箔の一方の面に塗布し、その後、乾燥し、上記のカリウム含有型正極材料とバインダー樹脂との混合物からなる塗膜が一方の面に形成されたアルミニウム箔を得る。
次いで、塗膜を加圧圧着し、乾燥して、アルミニウム箔の一方の面に正極合材層を有する集電体（正極）を作製する。
このようにして、高入力特性及びサイクル特性に優れるアルカリ金属イオン電池を得ることができる正極を作製することができる。
Next, a paint for forming a positive electrode or a paste for forming a positive electrode is applied to one surface of an aluminum foil, and then dried, so that a coating film composed of the above-mentioned mixture of a potassium-containing positive electrode material and a binder resin is applied to one surface. Obtain the formed aluminum foil.
Next, the coating film is pressure-bonded and dried to prepare a current collector (positive electrode) having a positive electrode mixture layer on one surface of the aluminum foil.
In this way, it is possible to manufacture a positive electrode capable of obtaining an alkali metal ion battery having excellent high input characteristics and cycle characteristics.
〔負極〕
負極としては、例えば、金属Ｌｉ、天然黒鉛、ハードカーボン等の炭素材料、Ｌｉ合金及びＬｉ４Ｔｉ５Ｏ１２、Ｓｉ（Ｌｉ４．４Ｓｉ）等の負極材料を含むものが挙げられる。
[Negative electrode]
Examples of the negative electrode include carbon materials such as metallic Li, natural graphite and hard carbon, and negative electrode materials such as Li alloy and Li 4 Ti 5 O 12 and Si (Li 4.4 Si).
〔電解質〕
電解質は、Ｌｉイオン、Ｎａイオン、及びＫイオンからなる群から選択される少なくとも１種を含む。
電解質は非水電解質であることが好ましく、例えば、炭酸エチレンと、炭酸ジエチルとを、質量比で１：１となるように混合し、得られた混合溶媒に六フッ化リン酸金属塩（ＭＰＦ６）を、例えば、濃度１モル／ｄｍ３となるように溶解したものが挙げられる。ここで、ＭＰＦ６において、Ｍは、Ｌｉイオン、Ｎａイオン、又はＫイオンを表す。ＭＰＦ６は１種のみ用いてもよいし、２種以上を混合して用いてもよい。
〔Electrolytes〕
The electrolyte contains at least one selected from the group consisting of Li ion, Na ion, and K ion.
The electrolyte is preferably a non-aqueous electrolyte. For example, ethylene carbonate and diethyl carbonate are mixed so as to have a mass ratio of 1: 1 and a metal hexafluoride phosphate (MPF) is added to the obtained mixed solvent. 6 ) is dissolved, for example, so as to have a concentration of 1 mol / dm 3 . Here, in MPF 6 , M represents Li ion, Na ion, or K ion. Only one type of MPF 6 may be used, or two or more types may be mixed and used.
〔セパレータ〕
本実施形態の正極と負極とは、セパレータを介して対向させることができる。セパレータとして、例えば、多孔質プロピレンを用いることができる。
また、非水電解質とセパレータの代わりに、固体電解質を用いてもよい。
[Separator]
The positive electrode and the negative electrode of the present embodiment can be opposed to each other via a separator. As the separator, for example, porous propylene can be used.
Further, a solid electrolyte may be used instead of the non-aqueous electrolyte and the separator.
本実施形態のアルカリ金属イオン電池は、正極が、本実施形態のアルカリ金属イオン電池正極材料を用いてなる正極合材層を有することから、電池構成部材のいずれの周囲においてもアルカリ金属イオン移動に優れ、高入力特性及びサイクル特性に優れる。そのため、電気自動車駆動用バッテリー、ハイブリッド自動車駆動用バッテリーなどに好適に用いられる。 In the alkali metal ion battery of the present embodiment, since the positive electrode has a positive electrode mixture layer made of the alkali metal ion battery positive electrode material of the present embodiment, alkali metal ion transfer can occur around any of the battery components. Excellent, high input characteristics and excellent cycle characteristics. Therefore, it is suitably used for a battery for driving an electric vehicle, a battery for driving a hybrid vehicle, and the like.
以下、実施例及び比較例を挙げて本発明を具体的に説明する。なお、本発明は、実施例に記載の形態に限定されるものではない。 Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is not limited to the embodiments described in the examples.
〔アルカリ金属イオン電池用正極材料の製造〕
（実施例１）
以下のようにして、ＫＮｉＰＯ４化合物を製造した。
Ｋ源およびＰ源としてＫ３ＰＯ４を、Ｎｉ源としてＮｉＳＯ４水溶液を用い、これらをモル比でＫ：Ｎｉ：Ｐ＝３：１：１となるように混合して、２．０Ｌの原料スラリーＡ１を調製した。
次いで、原料スラリーＡ１を耐圧容器に入れた。
その後、原料スラリーＡ１について、２５０℃にて４８時間、加熱反応を行い、水熱合成を行った。このときの耐圧容器内の圧力は０．８ＭＰａであった。
[Manufacturing of positive electrode materials for alkali metal ion batteries]
(Example 1)
The KNiPO 4 compound was produced as follows.
Using K 3 PO 4 as the K source and P source and NiSO 4 aqueous solution as the Ni source, these are mixed so as to have a molar ratio of K: Ni: P = 3: 1: 1 to obtain a raw material of 2.0 L. Slurry A1 was prepared.
Next, the raw material slurry A1 was placed in a pressure-resistant container.
Then, the raw material slurry A1 was subjected to a heating reaction at 250 ° C. for 48 hours to perform hydrothermal synthesis. The pressure in the pressure-resistant container at this time was 0.8 MPa.
反応後、耐熱容器内の雰囲気が室温になるまで冷却して、ケーキ状態の反応生成物の沈殿物を得た。
この沈殿物を蒸留水で複数回、充分に水洗し、乾燥しないように含水率４０％に保持し、ケーキ状物質とした。
このケーキ状物質を７０℃にて２時間真空乾燥させて、前駆体となるＫＮｉＰＯ４・Ｈ２Ｏ粒子を得た。
このＫＮｉＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱することにより、ＫＮｉＰＯ４粒子を得た。
After the reaction, the atmosphere in the heat-resistant container was cooled to room temperature to obtain a cake-like reaction product precipitate.
This precipitate was thoroughly washed with distilled water multiple times and kept at a water content of 40% so as not to dry, to form a cake-like substance.
This cake-like substance was vacuum dried at 70 ° C. for 2 hours to obtain KNiPO 4 · H 2 O particles as precursors.
The KNiPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain 4 KNiPO particles.
得られたＫＮｉＰＯ４粒子の９６質量％に対し、あらかじめ２０質量％に調整したポリビニルアルコール４質量％を水溶媒中に分散してなる原料スラリーＢ１を乾燥し造粒した。その後、７５０℃にて４時間加熱することにより、ＫＮｉＰＯ４粒子の表面を炭素質被膜によって被覆し、炭素質被覆正極活物質粒子を得た。 The raw material slurry B1 obtained by dispersing 4% by mass of polyvinyl alcohol prepared in advance to 20% by mass with respect to 96% by mass of the obtained 4 KNiPO particles in an aqueous solvent was dried and granulated. Then, the surface of the KNiPO 4 particles was coated with a carbonaceous film by heating at 750 ° C. for 4 hours to obtain carbonaceous coated positive electrode active material particles.
（実施例２）
以下のようにして、ＫＣｏＰＯ４化合物を製造した。
Ｋ源およびＰ源としてＫ３ＰＯ４を、Ｎｉ源としてＣｏＳＯ４水溶液を用い水溶液を用い、これらをモル比でＫ：Ｃｏ：Ｐ＝３：１：１となるように混合して、２．０Ｌの原料スラリーＡ２を調製した。
次いで、原料スラリーＡ２を耐圧容器に入れた。
その後、原料スラリーＡ２について、２２０℃にて４８時間、加熱反応を行い、水熱合成を行った。このときの耐圧容器内の圧力は０．８ＭＰａであった。
(Example 2)
The KCoPO 4 compound was produced as follows.
2. K 3 PO 4 was used as the K source and P source, and an aqueous solution was used using a CoSO 4 aqueous solution as the Ni source, and these were mixed so as to have a molar ratio of K: Co: P = 3: 1: 1. 0 L of raw material slurry A2 was prepared.
Next, the raw material slurry A2 was placed in a pressure-resistant container.
Then, the raw material slurry A2 was subjected to a heating reaction at 220 ° C. for 48 hours to perform hydrothermal synthesis. The pressure in the pressure-resistant container at this time was 0.8 MPa.
反応後、耐熱容器内の雰囲気が室温になるまで冷却して、ケーキ状態の反応生成物の沈殿物を得た。
この沈殿物を蒸留水で複数回、充分に水洗し、乾燥しないように含水率４０％に保持し、ケーキ状物質とした。
このケーキ状物質を７０℃にて２時間真空乾燥させて、前駆体となるＫＣｏＰＯ４・Ｈ２Ｏ粒子を得た。
このＫＣｏＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱することにより、ＫＣｏＰＯ４粒子を得た。
After the reaction, the atmosphere in the heat-resistant container was cooled to room temperature to obtain a cake-like reaction product precipitate.
This precipitate was thoroughly washed with distilled water multiple times and kept at a water content of 40% so as not to dry, to form a cake-like substance.
This cake-like substance was vacuum dried at 70 ° C. for 2 hours to obtain KCoPO 4 · H 2 O particles as precursors.
The KCoPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain KCoPO 4 particles.
得られたＫＣｏＰＯ４粒子の９６質量％に対し、あらかじめ２０質量％に調整したポリビニルアルコール４質量％を水溶媒中に分散してなる原料スラリーＢ２を乾燥し造粒した。その後、７５０℃にて４時間加熱することにより、ＫＣｏＰＯ４粒子の表面を炭素質被膜によって被覆し、炭素質被覆正極活物質粒子を得た。 The raw material slurry B2 prepared by dispersing 4% by mass of polyvinyl alcohol prepared in advance to 20% by mass with respect to 96% by mass of the obtained 4 KCoPO particles in an aqueous solvent was dried and granulated. Then, the surface of the KCoPO 4 particles was coated with a carbonaceous film by heating at 750 ° C. for 4 hours to obtain carbonaceous coated positive electrode active material particles.
（実施例３）
以下のようにして、ＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４化合物を製造した。
Ｋ源およびＰ源としてＫ３ＰＯ４を、Ｎｉ源としてＮｉＳＯ４水溶液、Ｃｏ源としてＣｏＳＯ４水溶液、Ａｌ源としてＡｌ２（ＳＯ４）３水溶液を用い、これらをモル比でＫ：Ｎｉ：Ｐ＝３：０．９：０．０５：０．０５：１となるように混合して、２．０Ｌの原料スラリーＡ３を調製した。
次いで、原料スラリーＡ３を耐圧容器に入れた。
その後、原料スラリーＡ３について、２５０℃にて４８時間、加熱反応を行い、水熱合成を行った。このときの耐圧容器内の圧力は０．８ＭＰａであった。
(Example 3)
KNi 0.9 Co 0.05 Al 0.05 PO 4 compound was produced as follows.
K 3 PO 4 was used as the K source and P source, NiSO 4 aqueous solution was used as the Ni source, CoSO 4 aqueous solution was used as the Co source, and Al 2 (SO 4 ) 3 aqueous solution was used as the Al source. A 2.0 L raw material slurry A3 was prepared by mixing so that the ratio was 3: 0.9: 0.05: 0.05: 1.
Next, the raw material slurry A3 was placed in a pressure-resistant container.
Then, the raw material slurry A3 was subjected to a heating reaction at 250 ° C. for 48 hours to perform hydrothermal synthesis. The pressure in the pressure-resistant container at this time was 0.8 MPa.
反応後、耐熱容器内の雰囲気が室温になるまで冷却して、ケーキ状態の反応生成物の沈殿物を得た。
この沈殿物を蒸留水で複数回、充分に水洗し、乾燥しないように含水率４０％に保持し、ケーキ状物質とした。
このケーキ状物質を７０℃にて２時間真空乾燥させて、前駆体となるＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４・Ｈ２Ｏ粒子を得た。
このＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱することにより、ＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４粒子を得た。
得られたＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４粒子の９６質量％に対し、あらかじめ２０質量％に調整したポリビニルアルコール４質量％を水溶媒中に分散してなる原料スラリーＢ３を乾燥し、造粒した。その後、７５０℃にて４時間加熱することにより、ＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４粒子の表面を炭素質被膜によって被覆し、炭素質被覆正極活物質粒子を得た。
After the reaction, the atmosphere in the heat-resistant container was cooled to room temperature to obtain a cake-like reaction product precipitate.
This precipitate was thoroughly washed with distilled water multiple times and kept at a water content of 40% so as not to dry, to form a cake-like substance.
This cake-like substance was vacuum-dried at 70 ° C. for 2 hours to obtain KNi 0.9 Co 0.05 Al 0.05 PO 4 · H 2 O particles as precursors.
The KNi 0.9 Co 0.05 Al 0.05 PO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain KNi 0.9 Co 0.05 Al 0.05 PO 4 particles. ..
A raw material slurry B3 obtained by dispersing 4% by mass of polyvinyl alcohol prepared in advance to 20% by mass in an aqueous solvent with respect to 96% by mass of the obtained KNi 0.9 Co 0.05 Al 0.05 PO 4 particles. It was dried and granulated. Then, by heating at 750 ° C. for 4 hours, the surface of the KNi 0.9 Co 0.05 Al 0.05 PO 4 particles was coated with a carbonaceous film to obtain carbonaceous coated positive electrode active material particles.
（実施例４）
実施例１と同様にしてＫＮｉＰＯ４・Ｈ２Ｏ粒子を得て、このＫＮｉＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱して、ＫＮｉＰＯ４粒子を得た。その後、得られたＫＣｏＰＯ４粒子の９７質量％に対し、あらかじめ２０質量％に調整したポリビニルアルコール３質量％を水溶媒中に分散してなる原料スラリーＢ４を乾燥し造粒し、炭素質被覆正極活物質粒子を得た。
(Example 4)
KNiPO 4 · H 2 O particles were obtained in the same manner as in Example 1, and the KNiPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain 4 KNiPO particles. Then, the raw material slurry B4 obtained by dispersing 3% by mass of polyvinyl alcohol adjusted to 20% by mass in advance in an aqueous solvent with respect to 97% by mass of the obtained 4 KCoPO particles was dried and granulated to form a carbonaceous coated positive electrode. Active material particles were obtained.
（実施例５）
実施例１と同様にしてＫＮｉＰＯ４・Ｈ２Ｏ粒子を得て、このＫＮｉＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱して、ＫＮｉＰＯ４粒子を得た。得られたＫＮｉＰＯ４粒子の９５質量％に対し、あらかじめ２０質量％に調整したポリビニルアルコール５質量％を水溶媒中に分散してなる原料スラリーＢ５を乾燥し造粒し、炭素質被覆正極活物質粒子を得た。
(Example 5)
KNiPO 4 · H 2 O particles were obtained in the same manner as in Example 1, and the KNiPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain 4 KNiPO particles. The raw material slurry B5, which is obtained by dispersing 5% by mass of polyvinyl alcohol adjusted to 20% by mass in advance in an aqueous solvent with respect to 95% by mass of the obtained 4 KNiPO particles, is dried and granulated to form a carbonaceous coated positive electrode active material. Obtained particles.
（比較例１）
実施例１と同様にしてＫＮｉＰＯ４・Ｈ２Ｏ粒子を得て、このＫＮｉＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱して、ＫＮｉＰＯ４粒子を得た。得られたＫＮｉＰＯ４粒子に炭素被覆を行わずにそのまま正極活物質粒子として用いた。
(Comparative Example 1)
KNiPO 4 · H 2 O particles were obtained in the same manner as in Example 1, and the KNiPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain 4 KNiPO particles. The obtained KNiPO 4 particles were used as they were as positive electrode active material particles without carbon coating.
（比較例２）
実施例２と同様にしてＫＣｏＰＯ４・Ｈ２Ｏ粒子を得て、このＫＣｏＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱して、ＫＣｏＰＯ４粒子を得た。得られたＫＣｏＰＯ４粒子に炭素被覆を行わずにそのまま正極活物質粒子として用いた。
(Comparative Example 2)
KCoPO 4 · H 2 O particles were obtained in the same manner as in Example 2, and the KCoPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain 4 KCoPO particles. The obtained KCoPO 4 particles were used as they were as positive electrode active material particles without carbon coating.
（比較例３）
実施例３と同様にしてＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４・Ｈ２Ｏ粒子を得て、このＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱して、ＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４粒子を得た。得られたＫＮｉ０．９Ｃｏ０．０５Ａｌ０．０５ＰＯ４粒子に炭素被覆を行わずにそのまま正極活物質粒子として用いた。
(Comparative Example 3)
KNi 0.9 Co 0.05 Al 0.05 PO 4 · H 2 O particles were obtained in the same manner as in Example 3, and the KNi 0.9 Co 0.05 Al 0.05 PO 4 · H 2 O particles were obtained. Was heated at 700 ° C. for 2 hours to obtain KNi 0.9 Co 0.05 Al 0.05 PO 4 particles. The obtained KNi 0.9 Co 0.05 Al 0.05 PO 4 particles were used as they were as positive electrode active material particles without carbon coating.
（比較例４）
実施例１と同様にしてＫＮｉＰＯ４・Ｈ２Ｏ粒子を得て、このＫＮｉＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱して、ＫＮｉＰＯ４粒子を得た。得られたＫＮｉＰＯ４粒子の９８質量％に対し、あらかじめ２０質量％に調整したポリビニルアルコール２質量％を水溶媒中に分散してなる原料スラリーＢ６を乾燥し造粒し、炭素質被覆正極活物質粒子を得た。
(Comparative Example 4)
KNiPO 4 · H 2 O particles were obtained in the same manner as in Example 1, and the KNiPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain 4 KNiPO particles. The raw material slurry B6, which is obtained by dispersing 2% by mass of polyvinyl alcohol prepared in advance to 20% by mass with respect to 98% by mass of the obtained 4 KNiPO particles in an aqueous solvent, is dried and granulated to form a carbonaceous coated positive electrode active material. Obtained particles.
（比較例５）
実施例１と同様にしてＫＮｉＰＯ４・Ｈ２Ｏ粒子を得て、このＫＮｉＰＯ４・Ｈ２Ｏ粒子を７００℃にて２時間加熱して、ＫＮｉＰＯ４粒子を得た。得られたＫＮｉＰＯ４粒子の９４質量％に対し、あらかじめ２０質量％に調整したポリビニルアルコール６質量％を水溶媒中に分散してなる原料スラリーＢ７乾燥し造粒し、炭素質被覆正極活物質粒子を得た。
(Comparative Example 5)
KNiPO 4 · H 2 O particles were obtained in the same manner as in Example 1, and the KNiPO 4 · H 2 O particles were heated at 700 ° C. for 2 hours to obtain 4 KNiPO particles. Raw material slurry B7 made by dispersing 6% by mass of polyvinyl alcohol prepared in advance to 20% by mass with respect to 94% by mass of the obtained 4 KNiPO particles was dried and granulated, and carbonaceous coated positive electrode active material particles. Got
実施例１～５及び比較例４～５の炭素質被膜を有する正極活物質粒子（炭素質被覆正極活物質粒子）、並びに比較例１～３の炭素質被膜を有しない正極活物質粒子を、それぞれ、アルカリ金属二次電池用正極材料として用いた。 The positive electrode active material particles having a carbonaceous coating of Examples 1 to 5 and Comparative Examples 4 to 5 (carbonaceous coated positive electrode active material particles), and the positive electrode active material particles having no carbonaceous coating of Comparative Examples 1 to 3 were used. Each was used as a positive electrode material for an alkali metal secondary battery.
〔正極材料の評価〕
実施例及び比較例で得られた正極材料、及び該正極材料が含む成分について物性を評価した。評価方法は、以下の通りである。結果を表１に示す。
[Evaluation of positive electrode material]
The physical properties of the positive electrode materials obtained in Examples and Comparative Examples and the components contained in the positive electrode materials were evaluated. The evaluation method is as follows. The results are shown in Table 1.
（１）炭素量
炭素分析計（堀場製作所社製、型番：ＥＭＩＡ－２２０Ｖ）を用いて、正極材料の炭素量を測定した。
(1) Carbon amount The carbon amount of the positive electrode material was measured using a carbon analyzer (manufactured by HORIBA, Ltd., model number: EMIA-220V).
（２）比表面積
比表面積計（日本ベル社製、商品名：ＢＥＬＳＯＲＰ－ｍｉｎｉ）を用いて、窒素（Ｎ２）吸着によるＢＥＴ法により、正極材料の比表面積を測定した。
(2) Specific surface area The specific surface area of the positive electrode material was measured by the BET method by adsorbing nitrogen (N 2 ) using a specific surface area meter (manufactured by Nippon Bell Co., Ltd., trade name: BELSORP-mini).
（３）正極活物質粒子の平均径
正極活物質粒子の一次粒子平均径と二次粒子平均径を、レーザー回折式粒度分布測定装置（島津製作所社製、商品名：ＳＡＬＤ－１０００）を用いて測定した。
(3) Average diameter of positive electrode active material particles The average diameter of primary particles and the average diameter of secondary particles of positive positive active material particles are measured using a laser diffraction type particle size distribution measuring device (manufactured by Shimadzu Corporation, trade name: SALD-1000). It was measured.
（４）ラマン特性（ＩＰＯ４／ＩＧ）
ラマン分光装置（堀場製作所社製、ＬａｂＲａｂ ＨＲ ｅｖｏｌｕｔｉｏｎ ＵＶ－ＶＩＳ－ＮＩＲ）を用いて正極材料のラマン分光測定を行った。
ラマン分光測定で１５５０～１６５０ｃｍ－１に観測されるＧバンドの最大強度ＩＧと、９３０～１０３０ｃｍ－１に測定されるＰＯ４バンドの最大強度ＩＰＯ４とを測定し、両者の比ＩＰＯ４／ＩＧを算出した。
(4) Raman characteristics (IPO4 / IG)
Raman spectroscopy of the positive electrode material was performed using a Raman spectroscope (LabRab HR evolution UV-VIS-NIR, manufactured by Horiba, Ltd.).
The maximum intensity IG of the G band observed from 1550 to 1650 cm -1 by Raman spectroscopy and the maximum intensity IPO4 of the PO4 band measured from 930 to 1030 cm -1 were measured, and the ratio IPO4 / IG of the two was calculated. ..
〔カリウムイオン二次電池の作製と評価〕
（１）ラミネート型カリウムイオン二次電池の作製
実施例１～５および比較例１～５のアルカリ金属二次電池用正極材料９０質量％、アセチレンブラック５質量％およびポリフッ化ビニリデン（ＰＶｄＦ）５質量％を、Ｎ－メチル－２－ピロリドン（ＮＭＰ）に加えて混合し、スラリーを調製した。
このスラリーを、厚さ１５μｍのアルミニウム箔からなる集電体に塗布し、乾燥した後、プレスすることにより正極を作製した。
[Manufacturing and evaluation of potassium ion secondary battery]
(1) Preparation of Laminated Potassium Ion Secondary Battery 90% by mass of positive electrode material for alkali metal secondary batteries of Examples 1 to 5 and Comparative Examples 1 to 5, 5% by mass of acetylene black, and 5% by mass of polyvinylidene fluoride (PVdF). % Was added to N-methyl-2-pyrrolidone (NMP) and mixed to prepare a slurry.
This slurry was applied to a current collector made of an aluminum foil having a thickness of 15 μm, dried, and then pressed to prepare a positive electrode.
天然黒鉛粉末９０質量％、アセチレンブラック５質量％およびポリフッ化ビニリデン（ＰＶｄＦ）５質量％を、Ｎ－メチル－２－ピロリドン（ＮＭＰ）に加えて混合し、スラリーを調製した。
このスラリーを、厚さ１５μｍの銅箔からなる集電体に塗布し、乾燥した後、プレスすることにより負極を作製した。
90% by mass of natural graphite powder, 5% by mass of acetylene black and 5% by mass of polyvinylidene fluoride (PVdF) were added to N-methyl-2-pyrrolidone (NMP) and mixed to prepare a slurry.
This slurry was applied to a current collector made of a copper foil having a thickness of 15 μm, dried, and then pressed to prepare a negative electrode.
得られた正極を２．８ｃｍ×２．６ｃｍに；負極を３．０ｃｍ×２．８ｃｍに；セパレータとして厚さ２５μｍの多孔質ポリプロピレンフィルムを３．２ｃｍ×３．２ｃｍに、それぞれ切断した。その後、正極と負極の塗布面の間にセパレータを配置し、これら電極とセパレータを２枚のアルミニウムラミネートフィルムで挟み、長辺の片側を除いた３辺を幅８ｍｍで熱封止し、電解液を注入した。その後、残りの一辺を熱封止して、ラミネート型カリウムイオン二次電池を作製した。電解液としては、炭酸エチレンと炭酸ジエチルとを１：１（質量比）にて混合し、さらに０．７ＭのＫＰＦ６溶液を加えて溶解したものを用いた。 The obtained positive electrode was cut into 2.8 cm × 2.6 cm; the negative electrode was cut into 3.0 cm × 2.8 cm; and a porous polypropylene film having a thickness of 25 μm as a separator was cut into 3.2 cm × 3.2 cm, respectively. After that, a separator is placed between the coated surfaces of the positive electrode and the negative electrode, these electrodes and the separator are sandwiched between two aluminum laminated films, and the three sides excluding one side of the long side are heat-sealed with a width of 8 mm to obtain an electrolytic solution. Was injected. Then, the remaining one side was heat-sealed to prepare a laminated potassium ion secondary battery. As the electrolytic solution, ethylene carbonate and diethyl carbonate were mixed at a ratio of 1: 1 (mass ratio), and a 0.7 M KPF 6 solution was further added and dissolved.
（２）カリウムイオン二次電池の評価
環境温度２５℃にて正極の電圧が天然黒鉛負極電圧に対して５．６Ｖになるまで電流値０．１ＣＡにて定電流充電を行い、目標電圧に到達した後、電流値が０．０１ＣＡになるまで定電圧充電を行った。
その後、１分間休止した後、環境温度２５℃にて、正極の電圧が天然黒鉛負極電圧に対して２．０Ｖになるまで０．１ＣＡの定電流放電を行い、０．１Ｃ放電容量を以下の基準で評価した。
○：０．１Ｃ放電容量が４０ｍＡｈ／ｇ以上でありカリウムイオン電気放電特性に優れる。
×：０．１Ｃ放電容量が４０ｍＡｈ／ｇ未満でありカリウムイオン電気放電特性に優れない。
結果を表１に示す。
(2) Evaluation of potassium ion secondary battery Constant current charging is performed at a current value of 0.1 CA until the positive voltage becomes 5.6 V with respect to the natural graphite negative voltage at an environmental temperature of 25 ° C, and the target voltage is reached. After that, constant voltage charging was performed until the current value reached 0.01 CA.
Then, after resting for 1 minute, a constant current discharge of 0.1 CA was performed at an ambient temperature of 25 ° C. until the voltage of the positive electrode became 2.0 V with respect to the voltage of the negative electrode of natural graphite, and the 0.1 C discharge capacity was set to the following. Evaluated by criteria.
◯: 0.1C The discharge capacity is 40 mAh / g or more, and the potassium ion electric discharge characteristics are excellent.
X: 0.1C The discharge capacity is less than 40mAh / g, and the potassium ion electric discharge characteristics are not excellent.
The results are shown in Table 1.
（結果のまとめ）
表１からわかるように、リン酸カリウム化合物の粒子表面に炭素被覆し、比ＩＰＯ４／ＩＧを０．０３≦ＩＰＯ４／ＩＧ≦０．３の範囲とすることで、カリウムイオン電池として高い放電特性が得られ高いエネルギー密度を得ることができる。
(Summary of results)
As can be seen from Table 1, by coating the surface of the potassium phosphate compound particles with carbon and setting the ratio IPO4 / IG in the range of 0.03 ≦ IPO4 / IG ≦ 0.3, high discharge characteristics as a potassium ion battery can be obtained. The obtained high energy density can be obtained.
本発明のアルカリ金属イオン電池用正極材料は、リチウムイオン、ナトリウムイオン、カリウムイオン等の各種アルカリ金属イオン二次電池の正極として有用である。 The positive electrode material for an alkali metal ion battery of the present invention is useful as a positive electrode for various alkali metal ion secondary batteries such as lithium ion, sodium ion, and potassium ion.
Claims (4)
ラマン分光測定で１５５０～１６５０ｃｍ－１に観測されるＧバンドの最大強度ＩＧに対する、９３０～１０３０ｃｍ－１に測定されるＰＯ４バンドの最大強度ＩＰＯ４の比ＩＰＯ４／ＩＧが０．０３≦ＩＰＯ４／ＩＧ≦０．３であるアルカリ金属イオン電池用正極材料。
但し、上記一般式において、ＡはＣｏ、Ｍｎ、及びＮｉからなる群から選択される少なくとも１種であり、ＤはＭｎ、Ｆｅ、Ｍｇ、Ｃａ、Ｓｒ、Ｂａ、Ｔｉ、Ｚｎ、Ｂ、Ａｌ、Ｇａ、Ｉｎ、Ｓｉ、Ｇｅ、Ｓｃ及びＹからなる群から選択される少なくとも１種であり、ｘ、ｙ、ｚは、０．９＜ｘ＜１．１、０．６５＜ｙ≦１．０、０≦ｚ＜０．３５、０．９＜ｙ＋ｚ＜１．１である。 It has particles of a compound represented by the general formula KxAyDzPO 4 and a carbonaceous film covering the surface of the particles.
The ratio of the maximum intensity IPO4 of the PO4 band measured from 930 to 1030 cm -1 to the maximum intensity IG of the G band observed from 1550 to 1650 cm -1 by Raman spectroscopy IPO4 / IG is 0.03 ≤ IPO4 / IG ≤ Positive electrode material for alkali metal ion batteries of 0.3.
However, in the above general formula, A is at least one selected from the group consisting of Co, Mn, and Ni, and D is Mn, Fe, Mg, Ca, Sr, Ba, Ti, Zn, B, Al, It is at least one selected from the group consisting of Ga, In, Si, Ge, Sc and Y, and x, y and z are 0.9 <x <1.1, 0.65 <y ≦ 1.0. , 0 ≦ z <0.35, 0.9 <y + z <1.1.
Ｌｉイオン、Ｎａイオン、及びＫイオンからなる群から選択される少なくとも１種を含む電解質と
を有するアルカリ金属イオン電池。 The positive electrode according to claim 3 and
An alkali metal ion battery having an electrolyte containing at least one selected from the group consisting of Li ion, Na ion, and K ion.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2006302671A (en) * | 2005-04-20 | 2006-11-02 | Mitsui Mining Co Ltd | Cathode material for lithium-ion secondary battery and its manufacturing method as well as lithium-ion secondary battery using same |
| JP2016157684A (en) * | 2015-02-24 | 2016-09-01 | 東レ株式会社 | Method for manufacturing carbon-coated polyanion based positive electrode active material particles, and intermediate particles for manufacturing carbon-coated polyanion based positive electrode active material particles |
| JP2018055886A (en) * | 2016-09-27 | 2018-04-05 | 株式会社Ｇｓユアサ | Carbon-coated positive electrode active material, method for manufacturing the same, positive electrode, and nonaqueous electrolyte power storage device |
| JP2019102247A (en) * | 2017-11-30 | 2019-06-24 | 国立研究開発法人産業技術総合研究所 | Potassium ion secondary battery cathode active material and secondary battery |
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| JP2016157684A (en) * | 2015-02-24 | 2016-09-01 | 東レ株式会社 | Method for manufacturing carbon-coated polyanion based positive electrode active material particles, and intermediate particles for manufacturing carbon-coated polyanion based positive electrode active material particles |
| JP2018055886A (en) * | 2016-09-27 | 2018-04-05 | 株式会社Ｇｓユアサ | Carbon-coated positive electrode active material, method for manufacturing the same, positive electrode, and nonaqueous electrolyte power storage device |
| JP2019102247A (en) * | 2017-11-30 | 2019-06-24 | 国立研究開発法人産業技術総合研究所 | Potassium ion secondary battery cathode active material and secondary battery |
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