JP2020047383A - Positive electrode active material, method for manufacturing the same, positive electrode and lithium ion battery - Google Patents
Positive electrode active material, method for manufacturing the same, positive electrode and lithium ion battery Download PDFInfo
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- 239000007774 positive electrode material Substances 0.000 title claims abstract description 58
- 229910001416 lithium ion Inorganic materials 0.000 title claims description 29
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims description 27
- 238000000034 method Methods 0.000 title claims description 24
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 239000002245 particle Substances 0.000 claims abstract description 51
- 239000011247 coating layer Substances 0.000 claims abstract description 42
- 239000000203 mixture Substances 0.000 claims abstract description 28
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 10
- 238000000576 coating method Methods 0.000 claims description 29
- 239000011248 coating agent Substances 0.000 claims description 25
- 238000001766 barrel sputter deposition Methods 0.000 claims description 11
- 229910052760 oxygen Inorganic materials 0.000 claims description 9
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 8
- 238000010304 firing Methods 0.000 claims description 8
- 239000001301 oxygen Substances 0.000 claims description 8
- 150000001875 compounds Chemical class 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 5
- 239000002994 raw material Substances 0.000 claims description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 abstract description 41
- 229910052759 nickel Inorganic materials 0.000 abstract description 14
- 239000007787 solid Substances 0.000 abstract description 3
- 239000011572 manganese Substances 0.000 description 13
- 229910013641 LiNbO 3 Inorganic materials 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 9
- 239000003792 electrolyte Substances 0.000 description 8
- 239000007784 solid electrolyte Substances 0.000 description 8
- 229910052748 manganese Inorganic materials 0.000 description 6
- 238000013459 approach Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 229910012851 LiCoO 2 Inorganic materials 0.000 description 4
- 239000002131 composite material Substances 0.000 description 4
- 239000007771 core particle Substances 0.000 description 4
- 239000008151 electrolyte solution Substances 0.000 description 4
- 238000011156 evaluation Methods 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000011149 active material Substances 0.000 description 3
- 239000006182 cathode active material Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 238000004438 BET method Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000004993 emission spectroscopy Methods 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 230000005764 inhibitory process Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 206010021143 Hypoxia Diseases 0.000 description 1
- 229910008029 Li-In Inorganic materials 0.000 description 1
- 229910015872 LiNi0.8Co0.1Mn0.1O2 Inorganic materials 0.000 description 1
- 229910001290 LiPF6 Inorganic materials 0.000 description 1
- 229910001228 Li[Ni1/3Co1/3Mn1/3]O2 (NCM 111) Inorganic materials 0.000 description 1
- 229910006670 Li—In Inorganic materials 0.000 description 1
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 1
- SOXUFMZTHZXOGC-UHFFFAOYSA-N [Li].[Mn].[Co].[Ni] Chemical compound [Li].[Mn].[Co].[Ni] SOXUFMZTHZXOGC-UHFFFAOYSA-N 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 150000004703 alkoxides Chemical class 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 229910000361 cobalt sulfate Inorganic materials 0.000 description 1
- 229940044175 cobalt sulfate Drugs 0.000 description 1
- KTVIXTQDYHMGHF-UHFFFAOYSA-L cobalt(2+) sulfate Chemical compound [Co+2].[O-]S([O-])(=O)=O KTVIXTQDYHMGHF-UHFFFAOYSA-L 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- PQVSTLUFSYVLTO-UHFFFAOYSA-N ethyl n-ethoxycarbonylcarbamate Chemical compound CCOC(=O)NC(=O)OCC PQVSTLUFSYVLTO-UHFFFAOYSA-N 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000001879 gelation Methods 0.000 description 1
- 239000002241 glass-ceramic Substances 0.000 description 1
- YWXYYJSYQOXTPL-SLPGGIOYSA-N isosorbide mononitrate Chemical compound [O-][N+](=O)O[C@@H]1CO[C@@H]2[C@@H](O)CO[C@@H]21 YWXYYJSYQOXTPL-SLPGGIOYSA-N 0.000 description 1
- 238000007561 laser diffraction method Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- GLXDVVHUTZTUQK-UHFFFAOYSA-M lithium hydroxide monohydrate Substances [Li+].O.[OH-] GLXDVVHUTZTUQK-UHFFFAOYSA-M 0.000 description 1
- 229940040692 lithium hydroxide monohydrate Drugs 0.000 description 1
- 229910003002 lithium salt Inorganic materials 0.000 description 1
- 159000000002 lithium salts Chemical class 0.000 description 1
- 229940099596 manganese sulfate Drugs 0.000 description 1
- 239000011702 manganese sulphate Substances 0.000 description 1
- 235000007079 manganese sulphate Nutrition 0.000 description 1
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical compound [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical compound [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 description 1
- 229940053662 nickel sulfate Drugs 0.000 description 1
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000011163 secondary particle Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000013077 target material Substances 0.000 description 1
- 239000013076 target substance Substances 0.000 description 1
- 239000011206 ternary composite Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
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
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- Battery Electrode And Active Subsutance (AREA)
Abstract
Description
本開示は、正極活物質、及び、その製造方法、並びに、正極、及びリチウムイオン電池に関する。より具体的には、ニッケルを含有する正極活物質、及び、その製造方法、並びに、正極、及びリチウムイオン電池に関する。 The present disclosure relates to a positive electrode active material, a method for producing the same, a positive electrode, and a lithium ion battery. More specifically, the present invention relates to a positive electrode active material containing nickel, a method for producing the same, a positive electrode, and a lithium ion battery.
現在のリチウムイオン二次電池は、電解液を用いる物が多い。この電解液は可燃性であるため発火のリスクが比較的高い。このため、代替品として、固体電解質を用いた全固体リチウムイオン二次電池(以下、全固体ＬＩＢと略す)の開発が各社にて進められている。 Many current lithium ion secondary batteries use an electrolytic solution. Since this electrolyte is flammable, the risk of ignition is relatively high. For this reason, as an alternative, the development of an all-solid-state lithium ion secondary battery (hereinafter, abbreviated as an all-solid-state LIB) using a solid electrolyte is being promoted by each company.
この全固体ＬＩＢは、電解液を用いる従来のリチウムイオン二次電池に比べて、上記の発火の危険性が少なくなる。その反面、リチウムイオンの伝導が粒子内および粒子間を通して行われるため、開発当初より安定動作に関する懸念が指摘されていた。 This all-solid-state LIB has a lower risk of ignition as compared with a conventional lithium-ion secondary battery using an electrolytic solution. On the other hand, since the conduction of lithium ions is carried out inside and between the particles, concerns have been pointed out about the stable operation from the beginning of development.
上記問題に対するアプローチとして、以下の手段が挙げられる：
（１）電極中に固体電解質を３割程度混合する、
（２）正極活物質粒子または正極活物質薄膜の界面にＬｉ化合物を被覆する、
（３）より高いリチウムイオン伝導率を有する固体電解質を採用する。
こうしたアプローチにより、従来のリチウムイオン二次電池と同様な安定動作の実現に近づきつつある。
Approaches to the above issues include the following:
(1) mixing about 30% of the solid electrolyte in the electrode;
(2) coating the interface of the cathode active material particles or the cathode active material thin film with a Li compound,
(3) Use a solid electrolyte having a higher lithium ion conductivity.
With such an approach, realization of a stable operation similar to that of a conventional lithium ion secondary battery is approaching.
上記アプローチ（２）に関連して、特許文献１では、ＬｉＣｏＯ2粉末粒子表面上へＬｉＮｂＯ3被覆層を設けることを開示している。更に、該文献では、その手段として、湿式法（Ｎｂ等を含むアルコキシド溶液を用いる方法）を開示している。また、特許文献２〜３では、被覆する手段として乾式法（バレルスパッタリング法）を開示している。 In connection with the above approach (2), Patent Document 1 discloses providing a LiNbO 3 coating layer on the surface of LiCoO 2 powder particles. Further, this document discloses a wet method (a method using an alkoxide solution containing Nb or the like) as the means. Patent Documents 2 and 3 disclose a dry method (barrel sputtering method) as a means for coating.
活物質の観点から、上記（２）のアプローチは、全固体ＬＩＢでの出力特性を向上させるのに非常に重要な技術となる可能性がある。例えば、特許文献１においてＬｉＣｏＯ2の表面をＬｉＮｂＯ3で被覆した材料が開示されている。これにより、ＬｉＣｏＯ2および固体電解質材料の間の界面抵抗を低減させ、電池の高出力化が図れる。しかし、それでも従来の電解液を使用したリチウムイオン二次電池の容量に匹敵する容量は得られていない。 From the viewpoint of the active material, the approach (2) may be a very important technique for improving the output characteristics of the all-solid-state LIB. For example, Patent Literature 1 discloses a material in which the surface of LiCoO 2 is coated with LiNbO 3 . Thereby, the interface resistance between LiCoO 2 and the solid electrolyte material is reduced, and the output of the battery can be increased. However, a capacity comparable to the capacity of a lithium ion secondary battery using a conventional electrolytic solution has not yet been obtained.
更に容量を上げる目的で、公知のＬｉＣｏＯ2やＬｉＮｉ1/3Ｃｏ1/3Ｍｎ1/3Ｏ2に代えて、容量の大きい物質を正極活物質として採用することが考えられている。より具体的には、ＬｉＮｉ0.8Ｃｏ0.1Ｍｎ0.1Ｏ2などのＮｉ／（Ｎｉ＋Ｃｏ＋Ｍｎ）モル比が０．８以上の物質(以下、ハイニッケルと略す)を正極活物質として採用することが考えられている。 For the purpose of further increasing the capacity, it has been considered to employ a material having a large capacity as the positive electrode active material instead of the known LiCoO 2 or LiNi 1/3 Co 1/3 Mn 1/3 O 2 . More specifically, it is considered that a substance having a Ni / (Ni + Co + Mn) molar ratio of 0.8 or more (hereinafter abbreviated as high nickel) such as LiNi 0.8 Co 0.1 Mn 0.1 O 2 is used as the positive electrode active material. I have.
ハイニッケル正極活物質は、電解液を用いる従来のリチウムイオン二次電池では、使用しづらいとみなされてきた。この理由として、スラリー作製時のゲル化が発生することや、上記の電解液やリチウム塩との相性が悪い点が挙げられる。しかし、全固体ＬＩＢでは、上述した問題点は回避できると予想される。そこで、これらのハイニッケル正極活物質を全固体ＬＩＢへ採用することにより、従来のリチウムイオン二次電池に匹敵する電池特性を確保できる期待が高まっていた。 High nickel positive electrode active materials have been regarded as difficult to use in conventional lithium ion secondary batteries using an electrolyte. The reason for this is that gelation occurs during the preparation of the slurry and that the compatibility with the above-mentioned electrolyte and lithium salt is poor. However, it is expected that the above-mentioned problems can be avoided with an all solid LIB. Therefore, there has been an increasing expectation that by adopting these high nickel positive electrode active materials for the all-solid-state LIB, battery characteristics comparable to conventional lithium ion secondary batteries can be secured.
そこで、発明者は、ハイニッケル正極活物質に、上記アプローチ（２）の方法を試してみた。より具体的には、発明者は、乾式被覆法を試してみた。しかし、結果として電池の容量自体は向上するものの、それでも、従来のリチウムイオン二次電池に匹敵する電池特性を確保することができなかった。発明者は、この原因を以下のように考えた。 Then, the inventor tried the method of the above approach (2) for a high nickel positive electrode active material. More specifically, the inventors tried a dry coating method. However, as a result, although the capacity of the battery itself is improved, battery characteristics comparable to those of the conventional lithium ion secondary battery could not be secured. The inventor considered this cause as follows.
一部の乾式被覆法では、被覆材となるＬｉＮｂＯ3粒子をサブミクロンサイズまでしか小さくできない。このことが原因となって、被覆量が少ない場合はＬｉＮｂＯ3をアイランド状にしか被覆しない（つまり、部分的な被覆となる）。従って、被覆されていない箇所において、被覆粒子と電解質とが直接接触してしまうことになる。一方で、被覆量を多くした場合、ほぼ全面コーティングがされるが、被覆層が厚くなり過ぎてしまう。被覆層が厚くなり過ぎてしまうと、Ｌｉイオンの移動が阻害されてしまう。このような被覆層の厚い材料を正極活物質として用いた場合、全固体ＬＩＢは、従来のリチウムイオン二次電池に比べて半分程度の容量しかない。 In some dry coating methods, LiNbO 3 particles serving as a coating material can be reduced only to a submicron size. Due to this, when the coating amount is small, LiNbO 3 is coated only in the form of islands (that is, partial coating). Therefore, the coated particles and the electrolyte come into direct contact with each other in the area that is not coated. On the other hand, when the coating amount is increased, almost the entire surface is coated, but the coating layer becomes too thick. If the coating layer is too thick, the movement of Li ions will be hindered. When such a material having a thick coating layer is used as the positive electrode active material, the all-solid-state LIB has only about half the capacity of a conventional lithium-ion secondary battery.
このように、正極活物質は多くの改良の余地が残されている。そこで、本開示は、ＬｉとＮｂの酸化物、好ましくはＬｉＮｂＯ3で被覆した新たなハイニッケル正極活物質を提供すること、以って全固体ＬＩＢにおける電池特性の改善を達成することを目的とする。 Thus, the positive electrode active material has much room for improvement. Therefore, the present disclosure aims to provide a new high-nickel positive electrode active material coated with an oxide of Li and Nb, preferably LiNbO 3 , thereby achieving an improvement in battery characteristics in an all-solid-state LIB. I do.
上記試行錯誤の結果から、本発明者は以下のように考えた。即ち、完全に被覆された状態（又はこれに近い状態）を確保しながらも、できる限り被覆層を薄くすることで、上記の問題を解消できる可能性がある。そこで、均一な被覆が可能なバレルスパッタ法を採用し、諸条件を検討した結果、所望の被覆層を実現できることを見出した。 From the results of the above trial and error, the present inventor considered as follows. That is, there is a possibility that the above problem can be solved by making the coating layer as thin as possible while ensuring a completely covered state (or a state close to this). Therefore, a barrel sputtering method capable of uniform coating was adopted, and various conditions were examined. As a result, it was found that a desired coating layer could be realized.
上記知見に基づいて完成した発明は、一側面において以下の発明を包含する。
（発明１）
正極活物質であって、
前記正極活物質は、粒子と被覆層とを含み、
前記粒子の組成は以下の式で表され、
ＬｉaＮｉbＣｏcＭｎdＯe
（ここで、
１．０≦ａ≦１．０５、
０．８≦ｂ≦０．９、
１．８≦ｅ≦２．２、
ｂ＋ｃ＋ｄ＝１）
前記被覆層の組成は、ＬｉとＮｂの酸化物で表され、
前記正極活物質の比表面積と、Ｎｂ含有量とが、以下の関係を満たす、正極活物質。
０．２５≦Ｙ／Ｘ≦０．６０（Ｘ＝比表面積（ｍ2／ｇ）、Ｙ＝Ｎｂ含有量（重量％））
（発明２）
発明１に記載の正極活物質であって、前記粒子のＤ５０が２〜１２μｍである、正極活物質。
（発明３）
発明１又は２に記載の正極活物質であって、以下の組成条件を満たす、正極活物質。
０．０５≦ｃ≦０．１９、
０．０１≦ｄ≦０．１
（発明４）
発明１〜３いずれか１つに記載の正極活物質であって、前記正極活物質の被覆層の厚みが４ｎｍ以下である、正極活物質。
（発明５）
発明１〜４いずれか１つに記載の正極活物質であって、前記Ｎｂ含有量が０．５重量％以下である、正極活物質。
（発明６）
発明１〜５いずれか１つに記載の正極活物質を製造するための方法であって、
以下の組成の化合物の原料を混合して、７００℃〜８００℃の温度で１２〜２４時間焼成し、焼成体を得る工程と、
ＬｉaＮｉbＣｏcＭｎdＯe
（前記式において、
１．０≦ａ≦１．０５、
０．８≦ｂ≦０．９、
１．８≦ｅ≦２．２、
ｂ＋ｃ＋ｄ＝１）
前記焼成体を粉砕して粒子を得る工程と、
前記粒子をＬｉとＮｂの酸化物で被覆する工程と、
を含み、
前記被覆する工程が、酸素分圧３０ａｔ％以下でバレルスパッタ法により被覆することを含む、該方法。
（発明７）
発明６に記載の方法であって、前記被覆する工程が、１〜４時間バレルスパッタ法により被覆することを含む、該方法。
（発明８）
発明１〜５いずれか１つに記載の正極活物質を含むリチウムイオン電池用正極。
（発明９）
発明８のリチウムイオン電池用正極を含むリチウムイオン電池。
The invention completed on the basis of the above findings includes the following inventions in one aspect.
(Invention 1)
A positive electrode active material,
The positive electrode active material includes particles and a coating layer,
The composition of the particles is represented by the following formula,
Li a Ni b Co c M n d O e
(here,
1.0 ≦ a ≦ 1.05,
0.8 ≦ b ≦ 0.9,
1.8 ≦ e ≦ 2.2,
b + c + d = 1)
The composition of the coating layer is represented by an oxide of Li and Nb,
A positive electrode active material, wherein the specific surface area of the positive electrode active material and the Nb content satisfy the following relationship.
0.25 ≦ Y / X ≦ 0.60 (X = specific surface area (m 2 / g), Y = Nb content (% by weight))
(Invention 2)
The positive electrode active material according to the first aspect, wherein the particles have a D50 of 2 to 12 μm.
(Invention 3)
The positive electrode active material according to invention 1 or 2, which satisfies the following composition conditions.
0.05 ≦ c ≦ 0.19,
0.01 ≦ d ≦ 0.1
(Invention 4)
The positive electrode active material according to any one of Inventions 1 to 3, wherein the coating layer of the positive electrode active material has a thickness of 4 nm or less.
(Invention 5)
The positive electrode active material according to any one of Inventions 1 to 4, wherein the Nb content is 0.5% by weight or less.
(Invention 6)
A method for producing a positive electrode active material according to any one of Inventions 1 to 5,
Mixing a raw material of a compound having the following composition and firing at a temperature of 700 ° C to 800 ° C for 12 to 24 hours to obtain a fired body;
Li a Ni b Co c M n d O e
(In the above formula,
1.0 ≦ a ≦ 1.05,
0.8 ≦ b ≦ 0.9,
1.8 ≦ e ≦ 2.2,
b + c + d = 1)
A step of crushing the fired body to obtain particles,
Coating the particles with an oxide of Li and Nb;
Including
The method, wherein the step of coating includes coating by a barrel sputtering method at an oxygen partial pressure of 30 at% or less.
(Invention 7)
7. The method according to claim 6, wherein the step of coating comprises coating by barrel sputtering for 1 to 4 hours.
(Invention 8)
A positive electrode for a lithium ion battery, comprising the positive electrode active material according to any one of Inventions 1 to 5.
(Invention 9)
A lithium ion battery including the positive electrode for a lithium ion battery according to Invention 8.
一側面において、正極活物質は、比表面積とＮｂ含有量とが特定の関係を有する。これにより、全固体ＬＩＢにおける電池特性の改善を実現できる。 In one aspect, the positive electrode active material has a specific relationship between the specific surface area and the Nb content. Thereby, the improvement of the battery characteristics in the all-solid-state LIB can be realized.
以下、本開示の発明を実施するための具体的な実施形態について説明する。以下の説明は、本開示の発明の理解を促進するためのものである。即ち、本発明の範囲を限定することを意図するものではない。 Hereinafter, specific embodiments for carrying out the invention of the present disclosure will be described. The following description is provided to facilitate understanding of the present disclosure. That is, it is not intended to limit the scope of the present invention.
１．正極活物質の特性
本開示は、一実施形態において、ハイニッケル正極活物質に関する。前記ハイニッケル正極活物質は、粒子と、該粒子を被覆する被覆層とを含むことができる。前記粒子は、以下の組成で表されるＬｉ複合化合物であってもよい。
ＬｉaＮｉbＣｏcＭｎdＯe
（ここで、
１．０≦ａ≦１．０５、
０．８≦ｂ≦０．９、
１．８≦ｅ≦２．２、
ｂ＋ｃ＋ｄ＝１）
1. The present disclosure, in one embodiment, relates to a high nickel positive electrode active material. The high nickel positive electrode active material may include particles and a coating layer that covers the particles. The particles may be a Li composite compound represented by the following composition.
Li a Ni b Co c M n d O e
(here,
1.0 ≦ a ≦ 1.05,
0.8 ≦ b ≦ 0.9,
1.8 ≦ e ≦ 2.2,
b + c + d = 1)
更なる一実施形態において、上記組成式中のＣｏ及びＭｎの存在比は、下記の通りであってもよい。
０．０５≦ｃ≦０．１９、
０．０１≦ｄ≦０．１、
更なる一実施形態において、上記組成式中の酸素の存在比ｅは２であってもよい。
In a further embodiment, the abundance ratio of Co and Mn in the composition formula may be as follows.
0.05 ≦ c ≦ 0.19,
0.01 ≦ d ≦ 0.1,
In a further embodiment, the abundance e of oxygen in the composition formula may be 2.
また、前記被覆層は、ＬｉとＮｂの酸化物を含んでもよく、より好ましくはＬｉＮｂＯ3で表される化合物を含んでもよい。これにより、上述したように、固体電解質と活物質との間の界面抵抗を減少させることができる。 Further, the coating layer may include an oxide of Li and Nb, and more preferably may include a compound represented by LiNbO 3 . Thereby, as described above, the interface resistance between the solid electrolyte and the active material can be reduced.
一実施形態において、被覆層を備えた正極活物質の比表面積は、１ｍ2／ｇ以下、好ましくは、０．９ｍ2／ｇ以下である。１ｍ2／ｇ以下であることにより、二次粒子の表面の凹凸が抑制され、緻密な粒子が形成されたものとみなすことができる。結果として、容量を向上させたリチウムイオン電池の形成が可能となる。比表面積の下限値については特に限定されないが、典型的には、０．１ｍ2／ｇ以上である。 In one embodiment, the specific surface area of the cathode active material provided with the coating layer is 1 m 2 / g or less, preferably 0.9 m 2 / g or less. When the particle size is 1 m 2 / g or less, irregularities on the surface of the secondary particles are suppressed, and it can be considered that dense particles are formed. As a result, it is possible to form a lithium ion battery having an improved capacity. Although the lower limit of the specific surface area is not particularly limited, it is typically 0.1 m 2 / g or more.
なお、本明細書における、比表面積は、以下の手順で測定した値を指す：
・対象物質を１５０℃で２時間脱気
・カンタクローム社製のＭｏｎｏｓｏｒｂにて、吸着ガスとしてＨｅ７０ａｔ％−Ｎ２３０ａｔ％混合ガスを使用し、ＢＥＴ法（１点法）にて測定する。
In the present specification, the specific surface area indicates a value measured by the following procedure:
Degas the target substance at 150 ° C. for 2 hours. Measure by BET method (one-point method) using Monosorb made by Cantachrome Co., using a mixed gas of He at 70 at% and N at 230 at% as an adsorption gas.
一実施形態において、被覆層を備えた正極活物質の粒径は、Ｄ５０が２〜１２μｍ、より好ましくは、２．５〜１０．５μｍであってもよい。上記範囲とすることで、容量を向上させることができる。 In one embodiment, the particle diameter of the positive electrode active material provided with the coating layer may have a D50 of 2 to 12 μm, more preferably 2.5 to 10.5 μm. With the above range, the capacity can be improved.
なお、本明細書における、Ｄ５０は、以下の手順で測定した値を指す：日機装株式会社製のマイクロトラックＭＴ３０００ＥＸ ＩＩによるレーザー回折法で測定した粒度分布における５０％径（メジアン径：頻度の累積が５０％となる粒子径）。 In the present specification, D50 indicates a value measured by the following procedure: 50% diameter (median diameter: cumulative frequency) in the particle size distribution measured by a laser diffraction method using Microtrack MT3000EX II manufactured by Nikkiso Co., Ltd. The particle diameter becomes 50%).
一実施形態において、被覆層の厚さは４ｎｍ以下、好ましくは３ｎｍ以下である。これにより、Ｌｉイオンの移動阻害等の悪影響を回避できる。下限値は、特に限定されないが、典型的には１ｎｍ以上であり、好ましくは２ｎｍ以上である。なお、被覆層の厚さは、走査型透過電子顕微鏡（ＳＴＥＭ）を用いた元素マッピング分析及びライン分析により測定することができる。 In one embodiment, the thickness of the coating layer is 4 nm or less, preferably 3 nm or less. As a result, adverse effects such as inhibition of the movement of Li ions can be avoided. The lower limit is not particularly limited, but is typically 1 nm or more, and preferably 2 nm or more. In addition, the thickness of the coating layer can be measured by element mapping analysis and line analysis using a scanning transmission electron microscope (STEM).
一実施形態において、正極活物質に全体（例えば、粒子の組成が上述したＬｉaＮｉbＣｏcＭｎdＯeであり、且つ被覆層の組成がＬｉとＮｂの酸化物（好ましくはＬｉＮｂＯ3）である場合、Ｌｉ、Ｎｉ、Ｍｎ、Ｃｏ、Ｏ及びＮｂの合計を１００ｗｔ％とする）に対するＮｂ含有量は０．５重量％以下であり、好ましくは、０．３９重量％以下であり、更に好ましくは０．３５重量％以下である。下限値は、特に限定されないが、好ましくは、０．０９重量％以上であり、更に好ましくは０．１５重量％以上である。なお、Ｎｂ含有量はＩＣＰ発光分光分析により測定可能である。 In one embodiment, the entire positive electrode active material (e.g., a Li a Ni b Co c Mn d O e the composition of the particles described above, and the composition of the coating layer is an oxide of Li and Nb (preferably LiNbO 3) , The total content of Li, Ni, Mn, Co, O and Nb is 100 wt%), the Nb content is 0.5% by weight or less, preferably 0.39% by weight or less, It is preferably at most 0.35% by weight. The lower limit is not particularly limited, but is preferably 0.09% by weight or more, and more preferably 0.15% by weight or more. The Nb content can be measured by ICP emission spectroscopy.
一実施形態において、正極活物質の比表面積と、Ｎｂ濃度とは、以下の関係を充足することができる。
０．２５≦Ｙ／Ｘ≦０．６０（Ｘ＝比表面積（ｍ2／ｇ）、Ｙ＝Ｎｂ含有量（重量％））
In one embodiment, the following relationship can be satisfied between the specific surface area of the positive electrode active material and the Nb concentration.
0.25 ≦ Y / X ≦ 0.60 (X = specific surface area (m 2 / g), Y = Nb content (% by weight))
上記Ｙ／Ｘの値の上限値は、好ましくは、０．５５以下であり、更に好ましくは、０．４５以下である。上記Ｙ／Ｘの値の下限値は、好ましくは、０．２７以上であり、更に好ましくは、０．３０以上である。 The upper limit of the value of Y / X is preferably 0.55 or less, and more preferably 0.45 or less. The lower limit of the value of Y / X is preferably 0.27 or more, and more preferably 0.30 or more.
比率Ｙ／Ｘの値を上記範囲とすることにより、容量を向上させることができる。上記式中の比表面積は、上述したＢＥＴ法により測定した値を指す。 By setting the value of the ratio Y / X within the above range, the capacity can be improved. The specific surface area in the above formula indicates a value measured by the above-described BET method.
上記関係式の技術的意義を以下説明する。
まず、被覆層が薄いとＬｉの移動阻害が低くなる等の理由から、被覆層は薄いことが好ましい。一方で、被覆層を薄くし過ぎると、粒子を完全に（又はこれに近い状態まで）覆うことができず、粒子と電解質が直接接触してしまい、望ましくない。従って、完全に（又はこれに近い状態まで）被覆する一方で、被覆層を極力薄くする必要がある。
The technical significance of the above relational expression will be described below.
First, it is preferable that the coating layer is thin because the thinner the coating layer, the lower the inhibition of Li migration. On the other hand, if the coating layer is too thin, the particles cannot be completely (or nearly) covered, and the particles and the electrolyte come into direct contact, which is undesirable. Therefore, it is necessary to make the coating layer as thin as possible while completely (or close to) coating.
同一の粒径において、完全に（又はこれに近い状態まで）被覆された場合と部分的に被覆された場合とを比較すると、被覆層の成分であるＮｂ濃度に差が生じる。即ち、部分的に被覆された場合の方が、Ｎｂ濃度が小さい。 Comparing the case where the coating is completely (or close to) with the same particle size and the case where the coating is partially coated, a difference occurs in the Nb concentration as a component of the coating layer. That is, the Nb concentration is lower when the coating is partially applied.
しかし、実際には様々な粒径が存在するため、必ずしもＮｂ濃度の大小だけで、両者（完全（又はこれに近い状態まで）に被覆された場合と部分的に被覆された場合）を判別できるわけではない。例えば、同程度被覆された場合であっても、粒径が大きくなれば、Ｎｂ濃度は小さくなる。そこで、比表面積とＮｂ濃度とを組み合わせたパラメータを採用する。これにより、粒径が大きくなることでＮｂ濃度が小さい場合と、部分的に被覆されたことでＮｂ濃度が小さい場合とを区別することができる。 However, since there are actually various particle sizes, it is not always necessary to determine only the magnitude of the Nb concentration to determine whether both are completely (or almost completely covered) or partially covered. Do not mean. For example, even when the particles are coated to the same extent, the Nb concentration decreases as the particle size increases. Therefore, a parameter obtained by combining the specific surface area and the Nb concentration is adopted. This makes it possible to distinguish between a case where the Nb concentration is low due to the increase in the particle diameter and a case where the Nb concentration is low due to the partial coverage.
即ち、粒径が大きくなることでＮｂ濃度が小さくなる場合、比表面積も同時に小さくなるので、両者の比をとることでオフセットできる。一方で、部分的に被覆されたことでＮｂ濃度が小さい場合は、こうしたオフセットは起こらず、両者の比は小さくなる。 That is, when the Nb concentration is decreased by increasing the particle diameter, the specific surface area is also decreased at the same time, so that the offset can be obtained by taking the ratio between the two. On the other hand, when the Nb concentration is small due to partial coverage, such offset does not occur, and the ratio between the two becomes small.
一方で、同一の粒径において、被覆層が薄い場合と厚い場合とを比較すると、被覆層が厚い方が、Ｎｂ濃度が大きい。 On the other hand, when the coating layer is thinner and thicker when the particle diameter is the same, the thicker the coating layer, the higher the Nb concentration.
しかし、実際には様々な粒径が存在するため、必ずしもＮｂ濃度の大小だけで、両者（被覆が厚い場合と被覆層が薄い場合）を判別できるわけではない。例えば、同程度の厚さの被覆層であっても、粒径が小さい場合の方が、相対的にＮｂ濃度が高くなってしまう。そこで、比表面積とＮｂ濃度とを組み合わせたパラメータを採用する。これにより、被覆層が厚くなることでＮｂ濃度が大きくなる場合と、粒径が小さいことでＮｂ濃度が大きくなる場合とを区別することができる。 However, since there are actually various particle sizes, it is not always possible to distinguish between the two cases (thick coating and thin coating layer) only by the magnitude of the Nb concentration. For example, even if the coating layers have the same thickness, the Nb concentration becomes relatively higher when the particle size is smaller. Therefore, a parameter obtained by combining the specific surface area and the Nb concentration is adopted. This makes it possible to distinguish between a case where the Nb concentration increases due to the thicker coating layer and a case where the Nb concentration increases due to the smaller particle size.
即ち、粒径が小さくなることでＮｂ濃度が大きくなる場合、比表面積も同時に大きくなるので、両者の比をとることでオフセットできる。一方で、被覆層が厚くなることでＮｂ濃度が大きい場合は、こうしたオフセットは起こらず、両者の比は大きくなる。 That is, when the Nb concentration increases due to a decrease in the particle diameter, the specific surface area also increases at the same time, so that the offset can be obtained by taking the ratio between the two. On the other hand, when the Nb concentration is large due to the thick coating layer, such offset does not occur, and the ratio between the two becomes large.
２．正極活物質の製造方法
２−１．Ｌｉ複合化合物粒子の製造方法
本開示の一実施形態に係るリチウムイオン電池用正極活物質の製造方法としては、まず、Ｎｉ組成がモル比で０．８以上であるＮｉ・Ｃｏ・Ｍｎの三元系複合水酸化物、又は、Ｎｉ・Ｃｏ・Ｍｎとの三元系複合水酸化物の前駆体を準備する。次に、当該複合水酸化物に、Ｌｉ源（炭酸Ｌｉ、水酸化Ｌｉ等）を、各原料の混合割合を調整してヘンシェルミキサー等で乾式混合した後、７００℃〜８００℃の温度で１２〜２４時間焼成することで、焼成体（正極活物質）を得る。その後、必要であれば、焼成体を、例えば、パルベライザー等を用いて解砕することにより正極活物質の粉体を得る。
2. Manufacturing method of positive electrode active material
2-1. Method for Producing Li Composite Compound Particles As a method for producing a positive electrode active material for a lithium ion battery according to an embodiment of the present disclosure, first, a ternary Ni / Co / Mn having a Ni composition of 0.8 or more in molar ratio is used. A composite hydroxide or a precursor of a ternary composite hydroxide with Ni.Co.Mn is prepared. Next, a Li source (Li carbonate, Li hydroxide, etc.) is dry-mixed with the composite hydroxide using a Henschel mixer or the like after adjusting the mixing ratio of each raw material, and then mixed at a temperature of 700 ° C to 800 ° C. By firing for ~ 24 hours, a fired body (positive electrode active material) is obtained. Thereafter, if necessary, the fired body is crushed using, for example, a pulverizer or the like to obtain a powder of a positive electrode active material.
本発明の更なる一実施形態において、上記焼成温度（７００℃〜８００℃）は、組成に応じて適宜調整することが好ましい。より具体的には、Ｎｉの比率に応じて、焼成温度を調整することが好ましい。本発明では、上述のようにＮｉの比率ｂを０．８〜０．９の範囲で規定している。例えば、当該範囲でＮｉの比率が比較的低い場合には、焼成温度を高めに設定し、Ｎｉの比率が比較的高い場合には、焼成温度を低めに設定することが好ましい。 In a further embodiment of the present invention, the firing temperature (700 ° C. to 800 ° C.) is preferably appropriately adjusted according to the composition. More specifically, it is preferable to adjust the firing temperature according to the ratio of Ni. In the present invention, the Ni ratio b is defined in the range of 0.8 to 0.9 as described above. For example, when the ratio of Ni is relatively low in the range, it is preferable to set the firing temperature higher, and when the ratio of Ni is relatively high, it is preferable to set the firing temperature lower.
２−２．被覆方法
一実施形態において、上記粉体は、更にＬｉとＮｂの酸化物（より好ましくはＬｉＮｂＯ3）で被覆することができる。被覆方法には湿式法と乾式法が含まれるが、当該実施形態では、乾式法、より具体的にはバレルスパッタ法を採用する。
2-2. In one embodiment of the coating method , the powder can be further coated with an oxide of Li and Nb (more preferably, LiNbO 3 ). The coating method includes a wet method and a dry method. In this embodiment, a dry method, more specifically, a barrel sputtering method is employed.
例えば、ＬｉＮｂＯ3ターゲット材を使用し、出力を３００〜７００Ｗの条件下でバレルスパッタを行うことができる。 For example, barrel sputtering can be performed using a LiNbO 3 target material at a power of 300 to 700 W.
バレルスパッタを実施する際の酸素分圧は特に限定されないが、３０ａｔ％以下であってもよい。酸素の存在により、酸素欠損の発生を抑制できる。例えば、酸素欠損が生じると空孔が形成される。これにより、電気伝導性が向上していまい、正極活物質の化学ポテンシャルが被覆層を通して固体電解質に印加される。結果として、被覆層と固体電解質の界面に高抵抗層が生じてしまう懸念がある。酸素分圧の下限値は特に限定されないが、典型的には０ｖｏｌ％以上であってもよい。 The oxygen partial pressure when performing the barrel sputtering is not particularly limited, but may be 30 at% or less. Oxygen deficiency can be suppressed by the presence of oxygen. For example, when oxygen vacancies occur, vacancies are formed. Thereby, the electric conductivity is improved, and the chemical potential of the positive electrode active material is applied to the solid electrolyte through the coating layer. As a result, there is a concern that a high resistance layer may be formed at the interface between the coating layer and the solid electrolyte. The lower limit of the oxygen partial pressure is not particularly limited, but may be typically 0 vol% or more.
所望の比表面積とＮｂ含有量との関係を実現する観点から、バレルスパッタを実施する時間を適切に調節することが好ましい。実施時間が長すぎると、被覆層が厚くなりすぎてしまう。一方で、実施時間が短すぎると、粒子を完全（又はこれに近い状態まで）に被覆することができず、部分的に被覆された状態となる。典型的には、実施時間は１ｈ〜４ｈである。下限値について、好ましくは、実施時間は１．５ｈ以上である。上限値については、３ｈ以下が好ましい。 From the viewpoint of realizing the desired relationship between the specific surface area and the Nb content, it is preferable to appropriately adjust the time for performing the barrel sputtering. If the operation time is too long, the coating layer becomes too thick. On the other hand, if the operation time is too short, the particles cannot be completely (or almost completely) coated, and become partially coated. Typically, the run time is between 1 h and 4 h. Regarding the lower limit, preferably, the operation time is 1.5 hours or more. The upper limit is preferably 3 hours or less.
実施時間は、他の要素を考慮しながら適宜調節することが好ましい。例えば、Ｎｉ、Ｃｏ、Ｍｎを全体としたＮｉのモル比率が、低い場合（例えばＮｉ／（Ｎｉ＋Ｃｏ＋Ｍｎ）≒０．８の場合）、実施時間は上記範囲内で相対的に長い時間にすることが好ましい。一方で、Ｎｉ、Ｃｏ、Ｍｎを全体としたＮｉのモル比率が、高い場合（例えばＮｉ／（Ｎｉ＋Ｃｏ＋Ｍｎ）≒０．９の場合）、実施時間は上記範囲内で相対的に短い時間にすることが好ましい。 It is preferable that the operation time is appropriately adjusted in consideration of other factors. For example, when the molar ratio of Ni as a whole of Ni, Co, and Mn is low (for example, Ni / (Ni + Co + Mn) ≒ 0.8), the implementation time may be set to a relatively long time within the above range. preferable. On the other hand, when the molar ratio of Ni as a whole of Ni, Co, and Mn is high (for example, Ni / (Ni + Co + Mn) ≒ 0.9), the implementation time should be relatively short within the above range. Is preferred.
３．リチウムイオン電池用正極及びリチウムイオン電池
このようにして得られたリチウムイオン電池用正極活物質を利用し、公知の手段に従い、リチウムイオン電池用正極を製造することができる。更には、前記正極を用いて、公知の手段に従い、リチウムイオン電池を作製することができる。
3. Lithium Ion Battery Positive Electrode and Lithium Ion Battery A positive electrode for a lithium ion battery can be produced using the thus obtained positive electrode active material for a lithium ion battery according to a known means. Furthermore, a lithium ion battery can be manufactured using the positive electrode according to a known means.
被覆前の粒子の平均粒子径Ｄ５０、及び比表面積については、上述の手法で評価した。また、電池の特性については以下のように評価した。 The average particle diameter D50 and the specific surface area of the particles before coating were evaluated by the above-described method. The characteristics of the battery were evaluated as follows.
−電池特性の評価（電解液系電池）−
正極活物質と、導電材と、バインダーを９０：５：５の割合で秤量し、バインダーを有機溶媒（Ｎ−メチルピロリドン）に溶解したものに、正極活物質と導電材とを混合してスラリー化し、Ａｌ箔上に塗布して乾燥後にプレスして正極とした。続いて、対極をＬｉとした評価用の２０３２型コインセルを作製し、電解液に１Ｍ−ＬｉＰＦ６をＥＣ−ＤＭＣ（１：１）に溶解したものを用いて、放電レート０．０５Ｃで得られた初期容量（２５℃、充電上限電圧：４．３Ｖ、放電下限電圧：３．０Ｖ）を測定した。
-Evaluation of battery characteristics (electrolyte battery)-
The positive electrode active material, the conductive material, and the binder were weighed at a ratio of 90: 5: 5, and the binder was dissolved in an organic solvent (N-methylpyrrolidone). It was applied on an Al foil, dried and pressed to obtain a positive electrode. Subsequently, a 2032 type coin cell for evaluation with Li as a counter electrode was prepared, and a 1M-LiPF6 dissolved in EC-DMC (1: 1) in an electrolytic solution was obtained at a discharge rate of 0.05C. The initial capacity (25 ° C., charge upper limit voltage: 4.3 V, discharge lower limit voltage: 3.0 V) was measured.
−電池特性の評価（全固体電池）−
固体電解質としてＬｉ2Ｓ−Ｐ2Ｓ5（７５：２５ｍｏｌ％）ガラスセラミックスを使用し、以下の要領でセルを作製した。
（１）正極活物質、電解質、アセチレンブラックを６０：３５：５の重量比となるように秤量、
（２）上記（１）の合材粉末を乳鉢で混合（全量で約５０ｍｇ）、
（３）適量の電解質を冶具に入れプレス、
（４）上記（２）で作製した適量の合材を冶具に入れ、プレス、
（５）上部を固定して反転させ下パンチを外す、
（６）負極のＬｉ−Ｉｎ箔を冶具に入れて下部を固定、
（７）加圧ネジで最終固定してシール用袋ナットを締める。
このセルを用いて放電レート０．０５Ｃで得られた初期容量（２５℃、充電上限電圧：３．７Ｖ、放電下限電圧：２．５Ｖ）にて測定した。セルは市販（宝泉製）で販売されているＫＰ−ＳｏｌｉｄＣｅｌｌとなる。
-Evaluation of battery characteristics (all-solid-state battery)-
A cell was produced in the following manner using Li 2 SP 2 S 5 (75:25 mol%) glass ceramic as a solid electrolyte.
(1) The positive electrode active material, the electrolyte, and acetylene black are weighed to have a weight ratio of 60: 35: 5,
(2) mixing the mixture powder of (1) above in a mortar (about 50 mg in total);
(3) An appropriate amount of electrolyte is put into a jig and pressed.
(4) Put an appropriate amount of the mixture prepared in (2) above into a jig, press
(5) Fix the upper part, turn it over and remove the lower punch,
(6) Put the Li-In foil of the negative electrode in a jig and fix the lower part,
(7) Finally fix with a pressure screw and tighten the cap nut for sealing.
Using this cell, measurement was performed at an initial capacity (25 ° C., charge upper limit voltage: 3.7 V, discharge lower limit voltage: 2.5 V) obtained at a discharge rate of 0.05 C. The cell is KP-SolidCell which is commercially available (manufactured by Hosen).
・コア粒子
市販の硫酸ニッケル、硫酸コバルト、硫酸マンガンを水溶液として、Ｎｉ、Ｃｏ、Ｍｎのモル比率が、表１の通りになるように混合し、十分撹拌しながらアルカリ（水酸化ナトリウム）溶液と共沈反応させ、ろ過、洗浄を実施した。反応方法は常法に従って実施した。その後、ＮｉとＣｏとＭｎの合計に対するＬｉのモル比（Ｌｉ／（Ｎｉ＋Ｃｏ＋Ｍｎ））が１．０２となるように、上記共沈反応物を水酸化リチウム１水和物と混合し、ローラーハースキルンで表１の条件で焼成し（焼成時間２４時間）、ロールミルとパルべライザーを用いて粒子径（Ｄ５０）が表１の通りになるように解砕し、コア粒子の粉末（リチウムニッケルコバルトマンガン酸化物）を得た。
Core particles Commercially available nickel sulfate, cobalt sulfate, and manganese sulfate are mixed as aqueous solutions so that the molar ratios of Ni, Co, and Mn are as shown in Table 1, and the mixture is thoroughly stirred with an alkali (sodium hydroxide) solution. A coprecipitation reaction was performed, followed by filtration and washing. The reaction was carried out according to a conventional method. Thereafter, the coprecipitated product was mixed with lithium hydroxide monohydrate so that the molar ratio of Li to the total of Ni, Co and Mn (Li / (Ni + Co + Mn)) was 1.02, and the mixture was mixed with a roller hearth kiln. Under the conditions shown in Table 1 (firing time: 24 hours), crushed using a roll mill and a pulverizer so that the particle size (D50) becomes as shown in Table 1, and powdered core particles (lithium nickel cobalt manganese) Oxide) was obtained.
・乾式被覆（バレルスパッタ）
上記コア粒子をバレルスパッタ用の装置（機器名：ユーテック社製）のバレル内に配置した。ターゲット金属として、ＬｉＮｂＯ3を配置した。反応性ガスとして、酸素（Ｏ2）を表１に示す分圧でバレル内に導入した。バレルを揺動させ、上記コア粒子を攪拌させ、同時にターゲット金属とバレルとの間に表１に示す出力で印加した。
・ Dry coating (barrel spatter)
The core particles were placed in a barrel of a device for barrel sputtering (device name: U-Tech). LiNbO 3 was arranged as a target metal. Oxygen (O 2 ) was introduced into the barrel at a partial pressure shown in Table 1 as a reactive gas. The barrel was rocked to agitate the core particles, and at the same time, a voltage was applied between the target metal and the barrel with the output shown in Table 1.
被覆後の膜厚及び放電容量等を上述方法により測定した。また、Ｎｂの含有量を、ＩＣＰ発光分光分析（日立ハイテクサイエンス社製、型番ＳＰＳ５５２０のＩＣＰ−ＯＥ）により測定した。結果を表１に示す。
実施例１〜１２の被覆後の活物質は、いずれもＹ／Ｘが０．２５〜０．６０の範囲内となっていた。そして、全固体電池としての電池特性の評価結果において、対応する比較例よりも優れていた。 Each of the coated active materials of Examples 1 to 12 had a Y / X in the range of 0.25 to 0.60. And in the evaluation result of the battery characteristics as an all-solid-state battery, it was superior to the corresponding comparative example.
比較例１〜７は、いずれもＹ／Ｘが０．２５〜０．６０の範囲外となっていた。 In each of Comparative Examples 1 to 7, Y / X was out of the range of 0.25 to 0.60.
比較例１はＹ／Ｘが大きくなっており、正極活物質の被覆層が厚すぎる状態となった。そして、組成及び粒径が同じである実施例２と比べると、電池特性が劣っていた。 In Comparative Example 1, Y / X was large, and the coating layer of the positive electrode active material was in a state of being too thick. The battery characteristics were inferior to those of Example 2 having the same composition and particle size.
比較例２はＹ／Ｘが小さくなっており、正極活物質の被覆層が不十分（担持）な状態となった。そして、組成及び粒径が同じである実施例２と比べると、電池特性が劣っていた。 In Comparative Example 2, Y / X was small, and the coating layer of the positive electrode active material was insufficient (supported). The battery characteristics were inferior to those of Example 2 having the same composition and particle size.
比較例３はＹ／Ｘが大きくなっており、正極活物質の被覆層が厚すぎる状態となった。そして、組成及び粒径が同じである実施例５と比べると、電池特性が劣っていた。 In Comparative Example 3, Y / X was large, and the coating layer of the positive electrode active material was in a state of being too thick. And the battery characteristics were inferior to Example 5 in which the composition and the particle size were the same.
比較例４はＹ／Ｘが小さくなっており、正極活物質の被覆層が不十分な状態となった。そして、組成及び粒径が同じである実施例５と比べると、電池特性が劣っていた。 In Comparative Example 4, Y / X was small, and the coating layer of the positive electrode active material was insufficient. And the battery characteristics were inferior to Example 5 in which the composition and the particle size were the same.
比較例５はＹ／Ｘが大きくなっており、正極活物質の被覆層が厚すぎる状態となった。そして、組成及び粒径が同じである実施例８と比べると、全固体セルにおいては、電池特性が劣っていた。 In Comparative Example 5, Y / X was large, and the coating layer of the positive electrode active material was in a state of being too thick. Then, as compared with Example 8 having the same composition and particle size, the battery characteristics were inferior in the all solid cells.
比較例６はＹ／Ｘが小さくなっており、正極活物質の被覆層が不十分な状態となった。そして、組成及び粒径が同じである実施例８と比べると、電池特性が劣っていた。 In Comparative Example 6, Y / X was small, and the coating layer of the positive electrode active material was insufficient. Then, as compared with Example 8 having the same composition and particle size, the battery characteristics were inferior.
比較例７はＹ／Ｘが大きくなっており、正極活物質の被覆層が厚すぎる状態となった。そして、組成及び粒径が同じである実施例１１と比べると、電池特性が劣っていた。 In Comparative Example 7, Y / X was large, and the coating layer of the positive electrode active material was in a state of being too thick. The battery characteristics were inferior to those of Example 11 having the same composition and particle size.
以上、本開示の発明の具体的な実施形態について説明してきた。上記実施形態は、具体例に過ぎず、本発明は上記実施形態に限定されない。例えば、特記しない限り、上述の実施形態の１つに開示された技術的特徴は、他の実施形態に提供することができる。また、特記しない限り、特定の方法については、一部の工程を他の工程の順序と入れ替えることも可能であり、特定の２つの工程の間に更なる工程を追加してもよい。本発明の範囲は、特許請求の範囲によって規定される。 Hereinabove, the specific embodiments of the present disclosure have been described. The above embodiments are merely specific examples, and the present invention is not limited to the above embodiments. For example, unless otherwise noted, technical features disclosed in one of the above embodiments can be provided in another embodiment. Unless otherwise specified, for a particular method, some steps may be interchanged with the order of the other steps, and additional steps may be added between the particular two steps. The scope of the present invention is defined by the appended claims.
Claims (9)
前記正極活物質は、粒子と被覆層とを含み、
前記粒子の組成は以下の式で表され、
ＬｉaＮｉbＣｏcＭｎdＯe
（ここで、
１．０≦ａ≦１．０５、
０．８≦ｂ≦０．９、
１．８≦ｅ≦２．２、
ｂ＋ｃ＋ｄ＝１）
前記被覆層の組成は、ＬｉとＮｂの酸化物で表され、
前記正極活物質の比表面積と、Ｎｂ含有量とが、以下の関係を満たす、正極活物質。
０．２５≦Ｙ／Ｘ≦０．６０（Ｘ＝比表面積（ｍ2／ｇ）、Ｙ＝Ｎｂ含有量（重量％）） A positive electrode active material,
The positive electrode active material includes particles and a coating layer,
The composition of the particles is represented by the following formula,
Li a Ni b Co c M n d O e
(here,
1.0 ≦ a ≦ 1.05,
0.8 ≦ b ≦ 0.9,
1.8 ≦ e ≦ 2.2,
b + c + d = 1)
The composition of the coating layer is represented by an oxide of Li and Nb,
A positive electrode active material, wherein the specific surface area of the positive electrode active material and the Nb content satisfy the following relationship.
0.25 ≦ Y / X ≦ 0.60 (X = specific surface area (m 2 / g), Y = Nb content (% by weight))
０．０５≦ｃ≦０．１９、
０．０１≦ｄ≦０．１ The positive electrode active material according to claim 1 or 2, which satisfies the following composition conditions.
0.05 ≦ c ≦ 0.19,
0.01 ≦ d ≦ 0.1
以下の組成の化合物の原料を混合して、７００℃〜８００℃の温度で１２〜２４時間焼成し、焼成体を得る工程と、
ＬｉaＮｉbＣｏcＭｎdＯe
（前記式において、
１．０≦ａ≦１．０５、
０．８≦ｂ≦０．９、
１．８≦ｅ≦２．２、
ｂ＋ｃ＋ｄ＝１）
前記焼成体を粉砕して粒子を得る工程と、
前記粒子をＬｉとＮｂの酸化物で被覆する工程と、
を含み、
前記被覆する工程が、酸素分圧３０ａｔ％以下でバレルスパッタ法により被覆することを含む、該方法。 A method for producing a positive electrode active material according to any one of claims 1 to 5,
Mixing a raw material of a compound having the following composition and firing at a temperature of 700 ° C to 800 ° C for 12 to 24 hours to obtain a fired body;
Li a Ni b Co c M n d O e
(In the above formula,
1.0 ≦ a ≦ 1.05,
0.8 ≦ b ≦ 0.9,
1.8 ≦ e ≦ 2.2,
b + c + d = 1)
A step of crushing the fired body to obtain particles,
Coating the particles with an oxide of Li and Nb;
Including
The method, wherein the step of coating includes coating by a barrel sputtering method at an oxygen partial pressure of 30 at% or less.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022201609A1 (en) * | 2021-03-22 | 2022-09-29 | Ｊｘ金属株式会社 | Positive electrode active material for all-solid-state lithium ion batteries, positive electrode for all-solid-state lithium ion batteries, all-solid-state lithium ion battery, and method for producing positive electrode active material for all-solid-state lithium ion batteries |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007004590A1 (en) * | 2005-07-01 | 2007-01-11 | National Institute For Materials Science | All-solid lithium battery |
| JP2009176644A (en) * | 2008-01-28 | 2009-08-06 | Sumitomo Electric Ind Ltd | Lithium cell |
| JP2009245913A (en) * | 2007-09-11 | 2009-10-22 | Sumitomo Electric Ind Ltd | Lithium battery |
| WO2010107084A1 (en) * | 2009-03-18 | 2010-09-23 | 株式会社三徳 | All-solid-state lithium battery |
| WO2012043321A1 (en) * | 2010-09-28 | 2012-04-05 | Ｄｏｗａホールディングス株式会社 | Lithium-transition metal oxide powder, method for producing same, positive electrode active material for lithium ion battery, and lithium ion secondary battery |
| WO2015037330A1 (en) * | 2013-09-12 | 2015-03-19 | トヨタ自動車株式会社 | Active material composite powder, lithium battery, method for producing active material composite powder, and method for manufacturing lithium battery |
| JP2017107827A (en) * | 2015-11-27 | 2017-06-15 | 住友金属鉱山株式会社 | Positive electrode active material for nonaqueous electrolyte secondary battery, and method for producing the same, and nonaqueous electrolyte secondary battery |
| JP2017174611A (en) * | 2016-03-23 | 2017-09-28 | トヨタ自動車株式会社 | Lithium ion battery and method for manufacturing the same |
| JP2018116784A (en) * | 2017-01-16 | 2018-07-26 | 株式会社日立製作所 | Positive electrode material for solid-state battery, solid-state battery, and method of manufacturing the solid-state battery |
| JP2019046716A (en) * | 2017-09-05 | 2019-03-22 | 住友金属鉱山株式会社 | Positive electrode active material for nonaqueous electrolyte secondary battery, method for manufacturing the same, and nonaqueous electrolyte secondary battery |
| WO2019065254A1 (en) * | 2017-09-28 | 2019-04-04 | Ｊｘ金属株式会社 | Positive electrode active material, method for producing same, positive electrode, and lithium ion battery |
| JP2019125510A (en) * | 2018-01-17 | 2019-07-25 | トヨタ自動車株式会社 | Positive electrode mixture for all-solid battery, positive electrode for all-solid battery, all-solid battery and manufacturing methods thereof |
| JP2019139862A (en) * | 2018-02-06 | 2019-08-22 | Ｊｘ金属株式会社 | Positive electrode active material for lithium ion battery, method for manufacturing the same, positive electrode for lithium ion battery and lithium ion battery |
-
2018
- 2018-09-14 JP JP2018172689A patent/JP6633161B1/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007004590A1 (en) * | 2005-07-01 | 2007-01-11 | National Institute For Materials Science | All-solid lithium battery |
| JP2009245913A (en) * | 2007-09-11 | 2009-10-22 | Sumitomo Electric Ind Ltd | Lithium battery |
| JP2009176644A (en) * | 2008-01-28 | 2009-08-06 | Sumitomo Electric Ind Ltd | Lithium cell |
| WO2010107084A1 (en) * | 2009-03-18 | 2010-09-23 | 株式会社三徳 | All-solid-state lithium battery |
| WO2012043321A1 (en) * | 2010-09-28 | 2012-04-05 | Ｄｏｗａホールディングス株式会社 | Lithium-transition metal oxide powder, method for producing same, positive electrode active material for lithium ion battery, and lithium ion secondary battery |
| WO2015037330A1 (en) * | 2013-09-12 | 2015-03-19 | トヨタ自動車株式会社 | Active material composite powder, lithium battery, method for producing active material composite powder, and method for manufacturing lithium battery |
| JP2017107827A (en) * | 2015-11-27 | 2017-06-15 | 住友金属鉱山株式会社 | Positive electrode active material for nonaqueous electrolyte secondary battery, and method for producing the same, and nonaqueous electrolyte secondary battery |
| JP2017174611A (en) * | 2016-03-23 | 2017-09-28 | トヨタ自動車株式会社 | Lithium ion battery and method for manufacturing the same |
| JP2018116784A (en) * | 2017-01-16 | 2018-07-26 | 株式会社日立製作所 | Positive electrode material for solid-state battery, solid-state battery, and method of manufacturing the solid-state battery |
| JP2019046716A (en) * | 2017-09-05 | 2019-03-22 | 住友金属鉱山株式会社 | Positive electrode active material for nonaqueous electrolyte secondary battery, method for manufacturing the same, and nonaqueous electrolyte secondary battery |
| WO2019065254A1 (en) * | 2017-09-28 | 2019-04-04 | Ｊｘ金属株式会社 | Positive electrode active material, method for producing same, positive electrode, and lithium ion battery |
| JP2019125510A (en) * | 2018-01-17 | 2019-07-25 | トヨタ自動車株式会社 | Positive electrode mixture for all-solid battery, positive electrode for all-solid battery, all-solid battery and manufacturing methods thereof |
| JP2019139862A (en) * | 2018-02-06 | 2019-08-22 | Ｊｘ金属株式会社 | Positive electrode active material for lithium ion battery, method for manufacturing the same, positive electrode for lithium ion battery and lithium ion battery |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022201609A1 (en) * | 2021-03-22 | 2022-09-29 | Ｊｘ金属株式会社 | Positive electrode active material for all-solid-state lithium ion batteries, positive electrode for all-solid-state lithium ion batteries, all-solid-state lithium ion battery, and method for producing positive electrode active material for all-solid-state lithium ion batteries |
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