JP4296274B2 - Lithium manganate positive electrode active material and all-solid lithium secondary battery - Google Patents
Lithium manganate positive electrode active material and all-solid lithium secondary battery Download PDFInfo
- Publication number
- JP4296274B2 JP4296274B2 JP2004089498A JP2004089498A JP4296274B2 JP 4296274 B2 JP4296274 B2 JP 4296274B2 JP 2004089498 A JP2004089498 A JP 2004089498A JP 2004089498 A JP2004089498 A JP 2004089498A JP 4296274 B2 JP4296274 B2 JP 4296274B2
- Authority
- JP
- Japan
- Prior art keywords
- positive electrode
- lithium
- active material
- secondary battery
- electrode active
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 title claims description 54
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims description 53
- 229910052744 lithium Inorganic materials 0.000 title claims description 53
- 239000007774 positive electrode material Substances 0.000 title claims description 35
- 239000007787 solid Substances 0.000 title claims description 29
- 239000002245 particle Substances 0.000 claims description 44
- 239000000203 mixture Substances 0.000 claims description 32
- 239000007784 solid electrolyte Substances 0.000 claims description 26
- 229910052748 manganese Inorganic materials 0.000 claims description 11
- 229910003480 inorganic solid Inorganic materials 0.000 claims description 9
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims description 6
- 229910052804 chromium Inorganic materials 0.000 claims description 5
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- 229910052802 copper Inorganic materials 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 229910052749 magnesium Inorganic materials 0.000 claims description 4
- 229910052759 nickel Inorganic materials 0.000 claims description 4
- 229910052596 spinel Inorganic materials 0.000 claims description 4
- 239000011029 spinel Substances 0.000 claims description 4
- 239000000843 powder Substances 0.000 description 37
- 239000011572 manganese Substances 0.000 description 31
- 238000009826 distribution Methods 0.000 description 17
- 229910052751 metal Inorganic materials 0.000 description 13
- 239000002184 metal Substances 0.000 description 13
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 12
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 9
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 8
- 150000002500 ions Chemical class 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 7
- 239000003792 electrolyte Substances 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 230000001186 cumulative effect Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000005259 measurement Methods 0.000 description 5
- 239000005486 organic electrolyte Substances 0.000 description 5
- 229920000139 polyethylene terephthalate Polymers 0.000 description 5
- 239000005020 polyethylene terephthalate Substances 0.000 description 5
- 238000003825 pressing Methods 0.000 description 5
- 239000002203 sulfidic glass Substances 0.000 description 5
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 4
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 4
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 4
- 238000007599 discharging Methods 0.000 description 4
- 229910001416 lithium ion Inorganic materials 0.000 description 4
- 229910015643 LiMn 2 O 4 Inorganic materials 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 150000008064 anhydrides Chemical class 0.000 description 3
- 230000006866 deterioration Effects 0.000 description 3
- 150000004677 hydrates Chemical class 0.000 description 3
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 description 3
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 239000004071 soot Substances 0.000 description 3
- 229910009343 Li1.33 Mn1.67 O4 Inorganic materials 0.000 description 2
- 239000011149 active material Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000003575 carbonaceous material Substances 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- PQVSTLUFSYVLTO-UHFFFAOYSA-N ethyl n-ethoxycarbonylcarbamate Chemical compound CCOC(=O)NC(=O)OCC PQVSTLUFSYVLTO-UHFFFAOYSA-N 0.000 description 2
- 229910052738 indium Inorganic materials 0.000 description 2
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 description 2
- 229910052808 lithium carbonate Inorganic materials 0.000 description 2
- KWGKDLIKAYFUFQ-UHFFFAOYSA-M lithium chloride Chemical compound [Li+].[Cl-] KWGKDLIKAYFUFQ-UHFFFAOYSA-M 0.000 description 2
- GLXDVVHUTZTUQK-UHFFFAOYSA-M lithium hydroxide monohydrate Substances [Li+].O.[OH-] GLXDVVHUTZTUQK-UHFFFAOYSA-M 0.000 description 2
- 229940040692 lithium hydroxide monohydrate Drugs 0.000 description 2
- IIPYXGDZVMZOAP-UHFFFAOYSA-N lithium nitrate Chemical compound [Li+].[O-][N+]([O-])=O IIPYXGDZVMZOAP-UHFFFAOYSA-N 0.000 description 2
- 229940093474 manganese carbonate Drugs 0.000 description 2
- 235000006748 manganese carbonate Nutrition 0.000 description 2
- 239000011656 manganese carbonate Substances 0.000 description 2
- HDJUVFZHZGPHCQ-UHFFFAOYSA-L manganese(2+);oxalate;dihydrate Chemical compound O.O.[Mn+2].[O-]C(=O)C([O-])=O HDJUVFZHZGPHCQ-UHFFFAOYSA-L 0.000 description 2
- 229910000016 manganese(II) carbonate Inorganic materials 0.000 description 2
- XMWCXZJXESXBBY-UHFFFAOYSA-L manganese(ii) carbonate Chemical compound [Mn+2].[O-]C([O-])=O XMWCXZJXESXBBY-UHFFFAOYSA-L 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- GCLGEJMYGQKIIW-UHFFFAOYSA-H sodium hexametaphosphate Chemical compound [Na]OP1(=O)OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])O1 GCLGEJMYGQKIIW-UHFFFAOYSA-H 0.000 description 2
- 235000019982 sodium hexametaphosphate Nutrition 0.000 description 2
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 229910018091 Li 2 S Inorganic materials 0.000 description 1
- 229910018111 Li 2 S-B 2 S 3 Inorganic materials 0.000 description 1
- 229910018130 Li 2 S-P 2 S 5 Inorganic materials 0.000 description 1
- 229910005630 Li1.05Mn1.95O4 Inorganic materials 0.000 description 1
- 229910009178 Li1.3Al0.3Ti1.7(PO4)3 Inorganic materials 0.000 description 1
- 229910009265 Li1.4Al0.4Ge1.6(PO4)3 Inorganic materials 0.000 description 1
- 229910015645 LiMn Inorganic materials 0.000 description 1
- 229910014689 LiMnO Inorganic materials 0.000 description 1
- 229910002099 LiNi0.5Mn1.5O4 Inorganic materials 0.000 description 1
- 229910021380 Manganese Chloride Inorganic materials 0.000 description 1
- GLFNIEUTAYBVOC-UHFFFAOYSA-L Manganese chloride Chemical compound Cl[Mn]Cl GLFNIEUTAYBVOC-UHFFFAOYSA-L 0.000 description 1
- 229910020346 SiS 2 Inorganic materials 0.000 description 1
- KLARSDUHONHPRF-UHFFFAOYSA-N [Li].[Mn] Chemical compound [Li].[Mn] KLARSDUHONHPRF-UHFFFAOYSA-N 0.000 description 1
- 150000001242 acetic acid derivatives Chemical class 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 239000006182 cathode active material Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 150000001869 cobalt compounds Chemical class 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 238000007580 dry-mixing Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- XIXADJRWDQXREU-UHFFFAOYSA-M lithium acetate Chemical compound [Li+].CC([O-])=O XIXADJRWDQXREU-UHFFFAOYSA-M 0.000 description 1
- 229910000625 lithium cobalt oxide Inorganic materials 0.000 description 1
- BFZPBUKRYWOWDV-UHFFFAOYSA-N lithium;oxido(oxo)cobalt Chemical compound [Li+].[O-][Co]=O BFZPBUKRYWOWDV-UHFFFAOYSA-N 0.000 description 1
- 229940071125 manganese acetate Drugs 0.000 description 1
- 235000002867 manganese chloride Nutrition 0.000 description 1
- 239000011565 manganese chloride Substances 0.000 description 1
- 229940099607 manganese chloride Drugs 0.000 description 1
- 150000002697 manganese compounds Chemical class 0.000 description 1
- IPJKJLXEVHOKSE-UHFFFAOYSA-L manganese dihydroxide Chemical compound [OH-].[OH-].[Mn+2] IPJKJLXEVHOKSE-UHFFFAOYSA-L 0.000 description 1
- UOGMEBQRZBEZQT-UHFFFAOYSA-L manganese(2+);diacetate Chemical compound [Mn+2].CC([O-])=O.CC([O-])=O UOGMEBQRZBEZQT-UHFFFAOYSA-L 0.000 description 1
- MIVBAHRSNUNMPP-UHFFFAOYSA-N manganese(2+);dinitrate Chemical compound [Mn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MIVBAHRSNUNMPP-UHFFFAOYSA-N 0.000 description 1
- RGVLTEMOWXGQOS-UHFFFAOYSA-L manganese(2+);oxalate Chemical compound [Mn+2].[O-]C(=O)C([O-])=O RGVLTEMOWXGQOS-UHFFFAOYSA-L 0.000 description 1
- PPNAOCWZXJOHFK-UHFFFAOYSA-N manganese(2+);oxygen(2-) Chemical class [O-2].[Mn+2] PPNAOCWZXJOHFK-UHFFFAOYSA-N 0.000 description 1
- PVIFNYFAXIMOKR-UHFFFAOYSA-M manganese(3+);oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Mn+3] PVIFNYFAXIMOKR-UHFFFAOYSA-M 0.000 description 1
- 239000002905 metal composite material Substances 0.000 description 1
- 229910000000 metal hydroxide Inorganic materials 0.000 description 1
- 150000004692 metal hydroxides Chemical class 0.000 description 1
- 229910021645 metal ion Inorganic materials 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 150000004682 monohydrates Chemical class 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 150000003891 oxalate salts Chemical class 0.000 description 1
- 230000033116 oxidation-reduction process Effects 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 229920001690 polydopamine Polymers 0.000 description 1
- -1 polyethylene terephthalate Polymers 0.000 description 1
- 238000000634 powder X-ray diffraction Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 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
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
- Secondary Cells (AREA)
- Battery Electrode And Active Subsutance (AREA)
Description
本発明は、無機固体電解質を電解質として用いる全固体リチウム二次電池用に適するマンガン酸リチウム系正極活物質及び該活物質を含む正極を用いた全固体リチウム二次電池に関する。 The present invention relates to a lithium manganate positive electrode active material suitable for an all solid lithium secondary battery using an inorganic solid electrolyte as an electrolyte, and an all solid lithium secondary battery using a positive electrode containing the active material.
最近の国内における携帯電話、ＰＤＡ、ノートパソコンなどのモバイル機器の急速な普及および高機能化に伴い、その電源としての二次電池の高性能化、低コスト化、安全性向上の要求は厳しさを増している。 As mobile devices such as mobile phones, PDAs, and notebook computers have been rapidly spread and enhanced in recent years, the demand for higher performance, lower cost, and improved safety of secondary batteries as power sources has become severe. Is increasing.
かかる要求に応え得る二次電池として、現状の二次電池の中で最大のエネルギー密度を有するリチウム二次電池の生産量が急速に伸びてきている。リチウム二次電池は、通常、コバルト酸リチウム等のリチウム−遷移金属複合酸化物を用いた正極、有機電解液及び炭素負極より構成されている。 As a secondary battery capable of meeting such demand, the production amount of a lithium secondary battery having the maximum energy density among the current secondary batteries is rapidly increasing. A lithium secondary battery is usually composed of a positive electrode using a lithium-transition metal composite oxide such as lithium cobaltate, an organic electrolyte, and a carbon negative electrode.
上記リチウム二次電池の構成部材の内、特に正極は電池電圧および容量を概ね決定づける重要な構成部材の一つである。現在、正極活物質として汎用されているコバルト酸リチウムは、高作動電圧かつ高容量で信頼性が高い反面、コバルト資源が希少でかつ偏在していることから原料コスト高を招いており低コスト化のための安価な正極活物質の開発が求められている。 Among the constituent members of the lithium secondary battery, the positive electrode is one of important constituent members that generally determine the battery voltage and capacity. Lithium cobalt oxide, which is currently widely used as a positive electrode active material, has high operating voltage, high capacity, and high reliability. On the other hand, cobalt resources are scarce and unevenly distributed, leading to higher raw material costs and lower costs. There is a need for the development of inexpensive cathode active materials for
コバルト酸リチウム系の正極活物質に代わり得る材料として、マンガン酸リチウム（ＬｉＭｎ2Ｏ4）系の材料が提案されている。その理由は、マンガン酸リチウム系材料は、コバルト酸リチウム系材料と類似した充放電特性を有し、かつコバルト化合物に比べ資源的に豊富で安価なマンガン化合物を原料として用いることができるからである。 A lithium manganate (LiMn 2 O 4 ) -based material has been proposed as a material that can replace the lithium cobaltate-based positive electrode active material. The reason is that the lithium manganate-based material has charge / discharge characteristics similar to those of the lithium cobaltate-based material, and can use as a raw material a manganese compound that is resource-rich and inexpensive compared to the cobalt compound. .
一方、安全性向上の面からは、現状の有機電解液に比べて化学的に安定でかつ漏液の心配がない無機固体電解質を電解質として用いた全固体リチウム二次電池が提案されており盛んに研究開発が行われている。 On the other hand, from the aspect of improving safety, all-solid lithium secondary batteries using an inorganic solid electrolyte that is chemically stable and has no risk of leakage as compared with current organic electrolytes have been proposed. Research and development is underway.
例えば、コバルト酸リチウム又はニッケル酸リチウムを正極活物質として用い、且つ硫化物系固体電解質を用いた全固体リチウム二次電池は、有機電解液を用いたリチウム二次電池に匹敵する優れた充放電特性を有することが明らかにされている（特許文献１参照）。また、マンガン酸リチウムを正極および負極の活物質として用い、リチウムイオン伝導性を有する結晶質酸化物からなる固体電解質を用いた全固体リチウム二次電池も提案されている（特許文献２参照）。 For example, an all-solid lithium secondary battery using lithium cobaltate or lithium nickelate as a positive electrode active material and using a sulfide-based solid electrolyte is excellent charge / discharge comparable to a lithium secondary battery using an organic electrolyte. It has been clarified to have characteristics (see Patent Document 1). An all-solid lithium secondary battery using a solid electrolyte made of a crystalline oxide having lithium ion conductivity using lithium manganate as an active material for positive and negative electrodes has also been proposed (see Patent Document 2).
しかしながら、これらの全固体リチウム二次電池において、有機電解質を用いるリチウム二次電池と同等以上の充放電サイクル特性を得るために、充放電サイクル特性に密接に関係する正極活物質−固体電解質接触界面でのリチウムイオン移動を考慮して、該二次電池用のマンガン酸リチウム正極活物質において、いかなる素材特性を有することが必要であるのかは未だ明らかにされていない。 However, in these all-solid lithium secondary batteries, in order to obtain charge / discharge cycle characteristics equivalent to or better than those of lithium secondary batteries using organic electrolytes, the positive electrode active material-solid electrolyte contact interface closely related to the charge / discharge cycle characteristics In view of the lithium ion migration in the battery, it has not been clarified yet what material characteristics are necessary for the lithium manganate positive electrode active material for the secondary battery.
従って、かかる素材特性の解明なしでは、良好な充放電サイクル特性を有する低コスト全固体リチウム二次電池の開発は困難である。
本発明は、高容量でかつ容量の劣化が抑制され、充放電サイクル特性に優れた全固体リチウム二次電池用に適したマンガン酸リチウム系正極活物質を提供することを主な目的とする。 The main object of the present invention is to provide a lithium manganate-based positive electrode active material suitable for use in an all-solid lithium secondary battery that has a high capacity, suppresses capacity deterioration, and has excellent charge / discharge cycle characteristics.
本発明者は、上記目的を達成すべく、鋭意検討を重ねた結果、立方晶スピネル型構造を有するマンガン酸リチウムの化学組成及び粒度分布を精密に制御することにより、優れた電池特性を有する全固体リチウム二次電池に適した正極活物質が得られることを見出し、本発明を完成するに至った。 As a result of intensive studies to achieve the above object, the present inventor has achieved excellent battery characteristics by precisely controlling the chemical composition and particle size distribution of lithium manganate having a cubic spinel structure. The inventors have found that a positive electrode active material suitable for a solid lithium secondary battery can be obtained, and have completed the present invention.
本発明は、以下のマンガン酸リチウム系正極活物質、これを含む正極及び全固体リチウム二次電池を提供するものである。 The present invention provides the following lithium manganate-based positive electrode active material, a positive electrode including the same, and an all-solid lithium secondary battery.
１．立方晶スピネル型構造を有し、組成式
Ｌｉ1+x（Ｍｎ2-yＭy）2-xＯ4 （Ｉ）
（式中、ＭはＡｌ、Ｍｇ、Ｃｒ、Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ又はＺｎを示す。ｘは、ＭがＭｎである場合は、０＜ｘ＜０．３３の範囲の数であり、ＭがＭｎ以外である場合は、０≦ｘ＜０．３３の範囲の数である。ｙは、０≦ｙ≦１の範囲の数である。）で表され、且つ１μｍ以下の粒子の存在比が４０重量％以下であるマンガン酸リチウム系正極活物質。
1. It has a cubic spinel structure and has the composition formula Li 1 + x (Mn 2- y My ) 2-x O 4 (I)
(In the formula, M represents Al, Mg, Cr, Mn, Fe, Co, Ni, Cu, or Zn. When M is Mn, x is a number in the range of 0 <x <0.33. In the case where M is other than Mn, the number is in the range of 0 ≦ x <0.33. Y is the number in the range of 0 ≦ y ≦ 1, and the particle size is 1 μm or less. A lithium manganate-based positive electrode active material having an abundance ratio of 40% by weight or less.
２．上記項１に記載された正極活物質を含む全固体リチウム二次電池用正極。 2. A positive electrode for an all-solid lithium secondary battery, comprising the positive electrode active material according to Item 1.
３．上記項２に記載された正極を用い、且つ無機固体電解質を用いた全固体リチウム二次電池。 3. An all-solid lithium secondary battery using the positive electrode described in the above item 2 and using an inorganic solid electrolyte.
４．無機固体電解質が、硫化物系無機固体電解質である上記項３に記載の全固体リチウム二次電池。 4). Item 4. The all-solid lithium secondary battery according to Item 3, wherein the inorganic solid electrolyte is a sulfide-based inorganic solid electrolyte.
本発明のマンガン酸リチウム系正極活物質は、高容量でかつ容量の劣化が抑制されており、充放電サイクル特性に優れた全固体リチウム二次電池用として好適に利用できる。 The lithium manganate positive electrode active material of the present invention has a high capacity and suppresses the deterioration of capacity, and can be suitably used for an all solid lithium secondary battery excellent in charge / discharge cycle characteristics.
従って、本発明のマンガン酸リチウム系正極活物質を用いた全固体リチウム二次電池は、該リチウム二次電池の低コスト化等に貢献し得る。 Therefore, the all-solid-state lithium secondary battery using the lithium manganate positive electrode active material of the present invention can contribute to cost reduction of the lithium secondary battery.
マンガン酸リチウム系正極活物質
本発明のマンガン酸リチウム系正極活物質は、Ｌｉ／Ｍｎ比に着目した特定の化学組成を有し、且つ特定の粒度分布即ち１μｍ以下（サブミクロン）の粒子をできる限り低減した粉体特性を有することにより、特徴付けられる。
Lithium manganate-based positive electrode active material The lithium manganate-based positive electrode active material of the present invention has a specific chemical composition focused on the Li / Mn ratio, and can produce particles with a specific particle size distribution, that is, 1 μm or less (submicron). Characterized by having as much reduced powder properties.
化学組成
本発明のマンガン酸リチウム系正極活物質は立方晶スピネル型構造を有し、組成式
Ｌｉ1+x（Ｍｎ2-yＭy）2-xＯ4 （Ｉ）
（式中、ＭはＡｌ、Ｍｇ、Ｃｒ、Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ又はＺｎを示す。ｘは、ＭがＭｎである場合は、０＜ｘ＜０．３３の範囲の数であり、ＭがＭｎ以外である場合は
、０≦ｘ＜０．３３の範囲の数である。ｙは、０≦ｙ≦１の範囲の数である。）で表される。
Chemical Composition The lithium manganate positive electrode active material of the present invention has a cubic spinel structure, and has the composition formula Li 1 + x (Mn 2− y My ) 2−x O 4 (I)
(In the formula, M represents Al, Mg, Cr, Mn, Fe, Co, Ni, Cu, or Zn. When M is Mn, x is a number in the range of 0 <x <0.33. , M is other than Mn, the number is in the range of 0 ≦ x <0.33, and y is the number in the range of 0 ≦ y ≦ 1.
組成式（Ｉ）において、ＭがＭｎである場合、即ち異種金属イオンを含まないマンガン酸リチウムの場合は、過剰リチウム量ｘ＝０（ＬｉＭｎ2Ｏ4）でないことが望ましい。これは、ＬｉＭｎ2Ｏ4の組成を作製しようとすると、以前の報告(T. Nakamura and A. Kajiyama, Solid State Ionics, 133, 195-202, (2000)及びR. Kanno, M. Yonemura, T. Kohigashi, Y. Kawamoto, M. Tabuchi and T. Kamiyama, J. Power Sources, 97-98, 423-426, (2001))に記載されているように、酸素欠損相ＬｉＭｎ2Ｏ4-d(０＜ｄ＜０．０３)が生
じやすく、立方晶構造が不安定となり結果としてｘ＞０の試料に比べて著しい充放電容量のサイクル劣化を導くことが報告されているためである。
In the composition formula (I), when M is Mn, that is, in the case of lithium manganate not containing a different metal ion, it is desirable that the amount of excess lithium is not x = 0 (LiMn 2 O 4 ). This, when you try to prepare a composition of LiMn 2 O 4, previously reported (T. Nakamura and A. Kajiyama, Solid State Ionics, 133, 195-202, (2000) and R. Kanno, M. Yonemura, T As described in Kohigashi, Y. Kawamoto, M. Tabuchi and T. Kamiyama, J. Power Sources, 97-98, 423-426, (2001)), the oxygen-deficient phase LiMn 2 O 4-d ( This is because 0 <d <0.03) is likely to occur, and the cubic structure becomes unstable, and as a result, it has been reported that significant cycle deterioration of charge / discharge capacity is induced as compared with a sample of x> 0.
また、ｘ＝０．３３となると、Ｌｉ1.33Ｍｎ1.67Ｏ4組成となりマンガンの形式電荷は
３．９９となりほぼ４価に近くなる。マンガン酸リチウムの場合３価のマンガンが充電により４価に変化することによってリチウム脱離が可能となり充電容量が得られること、現在用いられているリチウム二次電池はリチウムイオンを構造中に有しない炭素材料が用いられ、充電しないと電池として使用できないことを考慮すると、４価のマンガン価数を有するＬｉ1.33Ｍｎ1.67Ｏ4組成においては充電不可能なのでリチウム二次電池の正極活物
質として用いることができない。従ってｘ値はＭ＝Ｍｎの場合０＜ｘ＜０．３３に位置していることが望ましい。
Further, when x = 0.33, the composition becomes Li 1.33 Mn 1.67 O 4 , and the formal charge of manganese becomes 3.99, which is almost tetravalent. In the case of lithium manganate, trivalent manganese changes to tetravalent by charging, so that lithium can be removed and charge capacity can be obtained. Currently used lithium secondary batteries do not have lithium ions in the structure. Considering that carbon materials are used and cannot be used as a battery unless they are charged, Li 1.33 Mn 1.67 O 4 composition with a tetravalent manganese valence cannot be used for charging, so it should be used as a positive electrode active material for lithium secondary batteries. I can't. Therefore, it is desirable that the x value is located at 0 <x <0.33 when M = Mn.
一方、組成式（Ｉ）において、ＭがＭｎ以外の金属である場合、即ちＭｎ以外の異種金属を含む場合、例えば、ＬｉＮｉ0.5Ｍｎ1.5Ｏ4、ＬｉＣｒＭｎＯ4、ＬｉＣｏＭｎＯ4等
においては、Ｍｎイオンはすべて４価であるが、Ｎｉイオン、Ｃｏイオンが充放電可能元素として働くためｘ＝０であっても問題はない。このような化合物は、Ｍｎイオンの酸化還元電位である４Ｖに比べて高い５Ｖ領域にて充放電を行うため、有機電解液に比べ化学的安定性に優れた無機固体電解質を用いる全固体リチウム二次電池用正極活物質として好適に用いることができる。
On the other hand, in the composition formula (I), when M is a metal other than Mn, that is, when a different metal other than Mn is included, for example, in LiNi 0.5 Mn 1.5 O 4 , LiCrMnO 4 , LiCoMnO 4 , Mn ions are Although all are tetravalent, since Ni ions and Co ions work as chargeable / dischargeable elements, there is no problem even if x = 0. Such a compound charges and discharges in a 5 V region, which is higher than 4 V, which is the oxidation-reduction potential of Mn ions. Therefore, all-solid lithium secondary batteries using an inorganic solid electrolyte that is superior in chemical stability to organic electrolytes are used. It can be suitably used as a positive electrode active material for a secondary battery.
ｙ値に関しては、用いる金属種の価数や充放電時の作動電圧によって０から１の間で変化できる。これは、組成式中のマンガン価数（３価から４価の間でのみ変化）によって規定されているためである。上記のようにＮｉイオンを固溶させる場合、Ｎｉイオンは２価で入るため、組成式（Ｉ）においてマンガンがすべて４価になる組成までしか固溶させることができないので、ｙ＝０．５が固溶限界である。一方、ＣｏやＣｒイオンは３価で固溶するためマンガンがすべて４価になるのはｙ＝１までである。 The y value can vary between 0 and 1 depending on the valence of the metal species used and the operating voltage during charging and discharging. This is because it is defined by the manganese valence (changes only between trivalent and tetravalent) in the composition formula. When Ni ions are dissolved as described above, since Ni ions are divalent, y can be dissolved only up to a composition in which manganese is tetravalent in the composition formula (I). Is the solid solubility limit. On the other hand, since Co and Cr ions are trivalent and form a solid solution, all the manganese becomes tetravalent until y = 1.
粒度分布
本発明のマンガン酸リチウム系正極活物質は、１μｍ以下の粒子の存在比が４０重量％以下と規定している。その理由は、次の通りである。
Particle Size Distribution In the lithium manganate positive electrode active material of the present invention, the abundance ratio of particles of 1 μm or less is defined as 40% by weight or less. The reason is as follows.
全固体リチウム二次電池において正極活物質は、充放電時に粉末表面においてリチウムイオンおよび電子のやりとりを固体電解質、集電体との間で行っているため、粉体の比表面積が大きければ大きい（粒子径が小さい）ほど容易に上記界面でのイオン、電子のやりとりが行えることが期待できる。しかしながら、粒径の小さな粒子は、充填性に乏しく電極内に空隙が多く含まれるため、結果として固体電解質や集電体との界面接触面積が小さくなってしまい充放電サイクル特性が向上しないことが考えられる。そのため１μｍ以下（サブミクロン）の微粒子量はできる限り低減する必要がある。 In the all-solid-state lithium secondary battery, the positive electrode active material exchanges lithium ions and electrons between the solid electrolyte and the current collector on the surface of the powder during charge / discharge, so that the larger the specific surface area of the powder is, the larger ( It can be expected that the smaller the particle size), the easier the exchange of ions and electrons at the interface. However, particles with a small particle size are poor in packing properties and contain many voids in the electrode. As a result, the interface contact area with the solid electrolyte and current collector is reduced, and the charge / discharge cycle characteristics may not be improved. Conceivable. Therefore, it is necessary to reduce the amount of fine particles of 1 μm or less (submicron) as much as possible.
従って、本発明におけるマンガン酸リチウム系正極活物質は、１μｍ以下の粒子の存在比即ち含有量が４０重量％以下であることが必要である。また、当該物質の１μｍ以下の
粒子存在比は、３５重量％以下であることが好ましい。
Therefore, the lithium manganate positive electrode active material in the present invention is required to have an abundance ratio of particles of 1 μm or less, that is, a content of 40% by weight or less. Further, the particle abundance ratio of 1 μm or less of the substance is preferably 35% by weight or less.
本発明のマンガン酸リチウム系正極活物質の平均粒径は、通常、１０μｍ以下である。かかる粉末試料内のサブミクロン粒子含有量を見積もる方法としては、特に限定されないが、通常の粒度分布計、走査型電子顕微鏡観察による方法等を採用できる。例えば、レーザー回折・散乱式粒度分布計を用いて、試料を０．２重量％のヘキサメタリン酸ナトリウム水溶液などに分散させた後、０．０３μｍから２８０μｍまでの範囲で粒度分布測定を行い１μｍ以下の粒子含有量を算出できる。 The average particle diameter of the lithium manganate positive electrode active material of the present invention is usually 10 μm or less. A method for estimating the submicron particle content in the powder sample is not particularly limited, and a normal particle size distribution meter, a method by observation with a scanning electron microscope, or the like can be employed. For example, using a laser diffraction / scattering particle size distribution analyzer, the sample is dispersed in a 0.2% by weight sodium hexametaphosphate aqueous solution, and then the particle size distribution is measured in the range from 0.03 μm to 280 μm to 1 μm or less. The particle content can be calculated.
マンガン酸リチウム系正極活物質の製造方法
本発明の特定の化学組成及び特定の粒度分布を有するマンガン酸リチウム系正極活物質の製造方法は、特に限定されない。
Manufacturing method of lithium manganate positive electrode active material The manufacturing method of the lithium manganate positive electrode active material having a specific chemical composition and a specific particle size distribution of the present invention is not particularly limited.
例えば、リチウム源、マンガン源及び異種金属源を、所定モル比で、乾式混合又は湿式混合し、大気中、還元雰囲気中、酸化雰囲気中等で、５００〜１，２００℃程度の温度範囲で焼成し、必要に応じて、分級することにより、調製することができる。 For example, a lithium source, a manganese source, and a dissimilar metal source are dry-mixed or wet-mixed at a predetermined molar ratio and fired in a temperature range of about 500 to 1,200 ° C. in the air, in a reducing atmosphere, in an oxidizing atmosphere, or the like. If necessary, it can be prepared by classification.
上記製造方法において、８００℃以上の焼成温度域では、Ｌｉの揮発が顕著になるため目的組成より過剰のリチウム源を加えて焼成しても良い。また、得られた試料をふるい等を用いて分級することによって、サブミクロン粒子量を更に低減しても良い。 In the above manufacturing method, in a firing temperature range of 800 ° C. or higher, Li volatilization becomes significant, and therefore, an excess lithium source from the target composition may be added and fired. Further, the amount of submicron particles may be further reduced by classifying the obtained sample using a sieve or the like.
リチウム源としては、例えば、水酸化リチウム、炭酸リチウム、酢酸リチウム、硝酸リチウム、塩化リチウムなどの無水物、水和物等を使用することができる。マンガン源としては、例えば、水酸化マンガン、酸化水酸化マンガン、シュウ酸マンガン、マンガン酸化物、炭酸マンガン、酢酸マンガン、硝酸マンガン、塩化マンガンなどの無水物、水和物等を使用することができる。異種金属源としては、例えば、Ａｌ、Ｍｇ、Ｃｒ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ、Ｚｎ等の金属の水酸化物、酸化物、酸化水酸化物、炭酸塩、シュウ酸塩、硝酸塩、酢酸塩、塩化物などの無水物、水和物等を使用することができる。 As the lithium source, for example, anhydrides such as lithium hydroxide, lithium carbonate, lithium acetate, lithium nitrate, and lithium chloride, hydrates, and the like can be used. As the manganese source, for example, manganese hydroxide, manganese oxide hydroxide, manganese oxalate, manganese oxide, manganese carbonate, manganese acetate, manganese nitrate, manganese chloride and other anhydrides and hydrates can be used. . Examples of the different metal source include metal hydroxides such as Al, Mg, Cr, Fe, Co, Ni, Cu, and Zn, oxides, oxide hydroxides, carbonates, oxalates, nitrates, and acetates. Further, anhydrides such as chlorides, hydrates, and the like can be used.
得られたマンガン酸リチウム系正極活物質は、できる限りマンガン酸リチウム相単相であることが望ましいが、充放電特性に重大な劣化を引き起こさない限り、炭酸リチウム、水酸化リチウム、他のリチウムマンガン酸化物（Ｌｉ2ＭｎＯ3、ＬｉＭｎＯ2等)、マンガン酸化物、異種金属酸化物などが含まれていても良い。 The obtained lithium manganate-based positive electrode active material is desirably a single phase of lithium manganate phase as much as possible, but lithium carbonate, lithium hydroxide, other lithium manganese, and so on, as long as the charge / discharge characteristics are not seriously deteriorated. Oxides (Li 2 MnO 3 , LiMnO 2, etc.), manganese oxides, dissimilar metal oxides, and the like may be included.
得られた本発明のマンガン酸リチウム系正極活物質は、正極活物質として高い機能を有するものであり、必要に応じて、導電材、バインダー樹脂等を加え、常法に従って、正極を作製することができる。 The obtained lithium manganate-based positive electrode active material of the present invention has a high function as a positive electrode active material, and if necessary, a conductive material, a binder resin, etc. are added, and a positive electrode is produced according to a conventional method. Can do.
全固体リチウム二次電池
上記本発明マンガン酸リチウム系正極活物質を用いて作製した正極、固体電解質、負極等を構成部材として、充放電サイクル特性等に優れた全固体リチウム二次電池を調製することができる。
All-solid lithium secondary battery An all-solid lithium secondary battery having excellent charge / discharge cycle characteristics and the like is prepared using a positive electrode, a solid electrolyte, a negative electrode, etc., produced using the above-described lithium manganate-based positive electrode active material of the present invention. be able to.
電池構成部材は、上記正極を用いること、電解質として無機固体電解質を用いること以外は、特に限定されない。無機固体電解質としては、例えば、硫化物系固体電解質、酸素酸塩系固体電解質等を用いることができる。その中でも硫化物系固体電解質は室温で高いイオン導電性を示すこと、粒界抵抗が低いため電池作製が容易であることから特に好ましい。 The battery component is not particularly limited except that the positive electrode is used and an inorganic solid electrolyte is used as the electrolyte. As the inorganic solid electrolyte, for example, a sulfide solid electrolyte, an oxyacid salt solid electrolyte, or the like can be used. Among them, the sulfide-based solid electrolyte is particularly preferable because it exhibits high ionic conductivity at room temperature and the battery can be easily manufactured because of its low grain boundary resistance.
硫化物系固体電解質としては、例えば、Ｌｉ2Ｓ−Ｐ2Ｓ5、Ｌｉ2Ｓ−Ｂ2Ｓ3、Ｌｉ2Ｓ
−ＳｉＳ2系などのガラス系電解質、Ｌｉ4-xＧｅ1-xＰxＳ4（０．２≦０ｘ≦０．８）な
どの結晶系電解質を使用することができる。また、酸素酸塩系固体電解質としては、例えば、Ｌｉ1.3Ａｌ0.3Ｔｉ1.7（ＰＯ4）3、Ｌｉ1.4Ａｌ0.4Ｇｅ1.6（ＰＯ4）3などを使用することができる。
Examples of the sulfide-based solid electrolyte include Li 2 S—P 2 S 5 , Li 2 S—B 2 S 3 , and Li 2 S.
A glass-based electrolyte such as SiS 2 or a crystalline electrolyte such as Li 4-x Ge 1-x P x S 4 (0.2 ≦ 0x ≦ 0.8) can be used. Further, as the oxyacid salt solid electrolyte, for example, Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 , Li 1.4 Al 0.4 Ge 1.6 (PO 4 ) 3 can be used.
上記固体電解質は単体でも混合物でも用いることができ、正極と負極の間に介在させるだけでなくマンガン酸リチウム系正極活物質との界面接触面積を多く取るため正極側に混合させても良い。その混合方法も通常の乾式混合ばかりでなくアセトニトリルなどの溶媒を用いた湿式混合を必要に応じて使い分けることが出来る。また、その正極側に入れる固体電解質と正極−負極を隔てる電解質の種類は、充放電特性に重大な影響を及ぼさない限り一致させる必要はない。 The solid electrolyte may be used alone or as a mixture, and may be mixed not only between the positive electrode and the negative electrode but also on the positive electrode side in order to increase the interface contact area with the lithium manganate positive electrode active material. As the mixing method, not only normal dry mixing but also wet mixing using a solvent such as acetonitrile can be used as needed. The type of the electrolyte separating the solid electrolyte and the positive electrode-negative electrode placed on the positive electrode side does not need to be matched as long as the charge / discharge characteristics are not significantly affected.
負極としては、リチウム二次電池に用いられる炭素材料に加えて、金属リチウム、金属インジウム、金属アルミニウム、チタン酸リチウムなどを用いることができる。 As the negative electrode, in addition to the carbon material used for the lithium secondary battery, metallic lithium, metallic indium, metallic aluminum, lithium titanate, or the like can be used.
本発明の全固体リチウム二次電池は、例えば、次のようにして作製することができる。即ち、マンガン酸リチウム系正極活物質粉末と硫化物系固体電解質粉末を、グローブボックス中で、重量比７：３の割合で秤量後、試薬瓶に入れアセトニトリル溶媒およびジルコニアボールを加えよく振盪させた後、大気にさらすことなく６５℃で１時間程度真空乾燥することにより溶媒を除去して、正極合材粉末を得る。ポリエチレンテレフタレート（ＰＥＴ）管中に、硫化物固体電解質粉末を入れ、上下より金属押し棒に挟んだ後１８５ＭＰａにてプレスし、固体電解質層を形成する。その一方に作製した正極合材粉末を入れ同様に３７０ＭＰａにてプレスし、その後集電体であるチタンメッシュ及びチタン箔を正極合材の上に入れ、再度５５５ＭＰａにてプレスする。 The all solid lithium secondary battery of the present invention can be produced, for example, as follows. That is, lithium manganate-based positive electrode active material powder and sulfide-based solid electrolyte powder were weighed in a glove box at a weight ratio of 7: 3, placed in a reagent bottle, added with acetonitrile solvent and zirconia balls, and shaken well. Thereafter, the solvent is removed by vacuum drying at 65 ° C. for about 1 hour without exposure to the atmosphere to obtain a positive electrode mixture powder. A sulfide solid electrolyte powder is put into a polyethylene terephthalate (PET) tube, sandwiched between metal push bars from above and below, and pressed at 185 MPa to form a solid electrolyte layer. The positive electrode composite powder produced on one side is put and pressed in the same manner at 370 MPa, and then a titanium mesh and a titanium foil as current collectors are put on the positive electrode mixture and pressed again at 555 MPa.
図１に、全固体リチウム二次電池の一例の断面図を示す。図１のリチウム二次電池に、上記正極および電解質層を含むＰＥＴ管を組み込み、正極と反対側に負極としてインジウム金属箔を入れ、再度上部よりプレスすることにより全固体リチウム二次電池が作製できる。 FIG. 1 shows a cross-sectional view of an example of an all-solid lithium secondary battery. An all-solid lithium secondary battery can be produced by incorporating the PET tube including the positive electrode and the electrolyte layer into the lithium secondary battery of FIG. 1, inserting an indium metal foil as the negative electrode on the side opposite to the positive electrode, and pressing again from above. .
以下、実施例及び比較例を挙げて、本発明をより一層具体的に説明するが、本発明は実施例により限定されるものではない。 EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited by an Example.
なお、各例で得られた生成相は粉末Ｘ線回折測定により確認し、マンガン酸リチウム系粉末の形状は走査型電子顕微鏡（ＳＥＭ）観察した。また、マンガン酸リチウム系粉末の粒度分布は、レーザー回折・散乱式粒度分析計を用いて、測定した。 The production phase obtained in each example was confirmed by powder X-ray diffraction measurement, and the shape of the lithium manganate powder was observed with a scanning electron microscope (SEM). The particle size distribution of the lithium manganate powder was measured using a laser diffraction / scattering particle size analyzer.
実施例１
シュウ酸マンガン２水和物０．１ｍｏｌ（１７．９０ｇ）を秤量し、電気炉にて大気中４００℃、５時間熱分解して、０．０５ｍｏｌのＭｎ2Ｏ3微粉末を作製した。得られた粉末に対し水酸化リチウム１水和物をＬｉ／Ｍｎ比０．５４（０．０１３５ｍｏｌ）になる量（０．５６６ｇ）を加え、乾式法にて十分に混合した。混合物を５００ｋｇ／ｃｍ2で
錠剤成形後、電気炉に入れ、大気中８５０℃、１０時間焼成した。得られた粉末を加熱可能な圧力容器に入れ、酸素ガスを５ａｔｍまで導入後、４００℃、２０時間熱処理し、室温まで冷却後圧力容器より取り出し、目的とするマンガン酸リチウム系粉末（Ｌｉ1.05Ｍｎ1.95Ｏ4）を得た。
Example 1
Manganese oxalate dihydrate 0.1 mol (17.90 g) was weighed and pyrolyzed in an electric furnace at 400 ° C. in the air for 5 hours to produce 0.05 mol of Mn 2 O 3 fine powder. Lithium hydroxide monohydrate was added to the obtained powder in an amount (0.566 g) to give a Li / Mn ratio of 0.54 (0.0135 mol), and mixed well by a dry method. The mixture was tableted at 500 kg / cm 2 , placed in an electric furnace, and baked in the atmosphere at 850 ° C. for 10 hours. The obtained powder is put into a heatable pressure vessel, oxygen gas is introduced to 5 atm, heat treated at 400 ° C. for 20 hours, cooled to room temperature, taken out from the pressure vessel, and the target lithium manganate powder (Li 1.05 Mn 1.95 O 4 ) was obtained.
得られた試料のＸ線回折図形より、すべてのピークが From the X-ray diffraction pattern of the obtained sample, all the peaks are
図２に、得られた粉末のＳＥＭ写真を示す。このＳＥＭ観察により、この粉末は、粒子径０．５〜２μｍ程度の粒子からなっていることがわかった。 FIG. 2 shows an SEM photograph of the obtained powder. This SEM observation revealed that the powder was composed of particles having a particle size of about 0.5 to 2 μm.
図３（ｂ）に、得られた粉末の粒度分布の測定結果を示す。図中、縦棒が各粒径での分率、黒丸が累積分布を示す。測定は、粉末試料を、０．２重量％のヘキサメタリン酸ナトリウム水溶液に分散させた後、０．０３μｍから２８０μｍまでの範囲で粒度分布測定を行った。図３（ｂ）より、平均粒径２．４μｍ（図中の累積粒度分布が５０％の累積度数と交差する点）で、１μｍ以下の粒子の存在比は１７重量％と見積もられ、サブミクロン粒子量の少ないマンガン酸リチウム系粉末が得られていることがわかる。 FIG. 3B shows the measurement result of the particle size distribution of the obtained powder. In the figure, vertical bars indicate the fractions for each particle size, and black circles indicate the cumulative distribution. In the measurement, a powder sample was dispersed in a 0.2 wt% sodium hexametaphosphate aqueous solution, and then a particle size distribution measurement was performed in a range from 0.03 μm to 280 μm. From FIG. 3 (b), the abundance ratio of particles having an average particle diameter of 2.4 μm (the point where the cumulative particle size distribution in the figure intersects the cumulative frequency of 50%) is 1 μm or less is estimated to be 17% by weight. It can be seen that a lithium manganate powder having a small amount of micron particles is obtained.
得られた粉末２１０ｍｇをグローブボックス中で秤量し、粉砕した硫化物ガラス粉末（０．０１Ｌｉ3ＰＯ4−０．６３Ｌｉ2Ｓ−０．３６ＳｉＳ2組成）９０ｍｇとともに試料瓶に入れた。この試料瓶に、ジルコニアビーズおよびアセトニトリル５ｍｌを加え、ふたをして１０分間振盪した。振盪後、試料瓶を大気にさらすことなく真空乾燥器に入れ６５℃、１時間程度真空乾燥してアセトニトリルを蒸散させた。得られた正極合材を室温まで冷却後、電池試験用に用いた。 210 mg of the obtained powder was weighed in a glove box, and placed in a sample bottle together with 90 mg of pulverized sulfide glass powder (0.01Li 3 PO 4 -0.63Li 2 S-0.36SiS 2 composition). To this sample bottle, zirconia beads and 5 ml of acetonitrile were added, capped and shaken for 10 minutes. After shaking, the sample bottle was placed in a vacuum dryer without exposing to the atmosphere, and vacuum dried at 65 ° C. for about 1 hour to evaporate acetonitrile. The obtained positive electrode mixture was cooled to room temperature and then used for battery testing.
粉砕した硫化物ガラス粉末（０．０１Ｌｉ3ＰＯ4−０．６３Ｌｉ2Ｓ−０．３６ＳｉＳ2組成）７０ｍｇと上記正極合材２０ｍｇをグローブボックス中で秤量した。 70 mg of the ground sulfide glass powder (0.01Li 3 PO 4 -0.63Li 2 S-0.36SiS 2 composition) and 20 mg of the positive electrode mixture were weighed in a glove box.
図１中の内径１０ｍｍのＰＥＴ管と金属押し棒を用いて、ＰＥＴ管内に硫化物ガラス粉末を充填し、１８５ＭＰａにて乾式プレスし固体電解質層を形成した。プレス後、金属押し棒の片側を開け、正極合材を充填し３７０ＭＰａにて乾式プレスし正極合材層を固体電解質層上に形成させた。プレス後、金属押し棒の正極合材充填側を開け、１０ｍｍ径の金属チタニウムメッシュを入れ、５５５ＭＰａにて乾式プレスし正極合材内にメッシュを充填した。プレス後、正極と反対側の金属押し棒をはずし、固体電解質層のひび割れ、剥離などの問題がないことを確認後、厚み０．３ｍｍ、直径１０ｍｍの金属インジウム箔を入れて図１のような電気化学セル内に導入し、押し棒上部よりさらに締め付けて試験用セルを作製した。 The PET tube was filled with sulfide glass powder using a PET tube having an inner diameter of 10 mm and a metal push rod in FIG. 1, and dry-pressed at 185 MPa to form a solid electrolyte layer. After pressing, one side of the metal push rod was opened, filled with the positive electrode mixture, and dry pressed at 370 MPa to form a positive electrode mixture layer on the solid electrolyte layer. After pressing, the positive electrode mixture filling side of the metal push bar was opened, a 10-mm diameter metal titanium mesh was put in, and dry pressing was performed at 555 MPa, and the positive electrode mixture was filled with the mesh. After pressing, remove the metal push rod on the opposite side of the positive electrode, confirm that there are no problems such as cracking and peeling of the solid electrolyte layer, and then insert a metal indium foil with a thickness of 0.3 mm and a diameter of 10 mm as shown in FIG. The sample was introduced into the electrochemical cell and further tightened from the top of the push rod to prepare a test cell.
図４に、上記試験用セルを電位範囲２．３〜３．９Ｖ、電流量０．０６４ｍＡ／ｃｍ2
にて、充電より充放電試験を１０サイクルまで行って得られた充放電曲線を示す。初期充電容量は５５ｍＡｈ／ｇ、初期放電容量は４３ｍＡｈ／ｇであり、１０サイクル後の充電容量は４１ｍＡｈ／ｇで放電容量は３９ｍＡｈ／ｇであった。これら充放電特性データより、得られたマンガン酸リチウム系正極活物質は、全固体リチウム二次電池において良好な充放電特性を示すことが明らかである。
FIG. 4 shows that the test cell has a potential range of 2.3 to 3.9 V and a current amount of 0.064 mA / cm 2.
The charging / discharging curve obtained by performing a charging / discharging test to 10 cycles from charge is shown. The initial charge capacity was 55 mAh / g, the initial discharge capacity was 43 mAh / g, the charge capacity after 10 cycles was 41 mAh / g, and the discharge capacity was 39 mAh / g. From these charge / discharge characteristic data, it is clear that the obtained lithium manganate-based positive electrode active material exhibits good charge / discharge characteristics in an all-solid lithium secondary battery.
実施例２
炭酸マンガンを、大気中５５０℃、５時間熱処理することによって得たＭｎ2Ｏ3を０．０５ｍｏｌ（７．８９ｇ）秤量し、Ｌｉ／Ｍｎ比０．６０に相当する０．０１５ｍｏｌの水酸化リチウム１水和物０．６２９ｇを加え、乾式法にて十分に混合後、実施例１と同様に錠剤成形し、電気炉を用いて酸素気流中９００℃、２０時間焼成後、室温まで炉冷する
ことにより、目的とするマンガン酸リチウム系粉末（Ｌｉ1.13Ｍｎ1.87Ｏ4）を得た。
Example 2
0.05 mol (7.89 g) of Mn 2 O 3 obtained by heat-treating manganese carbonate in the atmosphere at 550 ° C. for 5 hours was weighed, and 0.015 mol of lithium hydroxide corresponding to a Li / Mn ratio of 0.60 Add 0.629 g of monohydrate, mix well by dry method, and form tablets in the same manner as in Example 1. After baking in an oxygen stream at 900 ° C. for 20 hours, cool to room temperature. As a result, a target lithium manganate powder (Li 1.13 Mn 1.87 O 4 ) was obtained.
得られた試料のＸ線回折図形より、すべてのピークが From the X-ray diffraction pattern of the obtained sample, all the peaks are
図３（ｃ）に、得られた粉末の粒度分布を、実施例１と同様にして測定した結果を示す。図中、縦棒が各粒径での分率、黒丸が累積分布を示す。図３（ｃ）より、平均粒径６．６μｍ、サブミクロン粒子存在比６重量％のマンガン酸リチウム系正極活物質であることがわかった。 FIG. 3C shows the result of measuring the particle size distribution of the obtained powder in the same manner as in Example 1. In the figure, vertical bars indicate the fractions for each particle size, and black circles indicate the cumulative distribution. FIG. 3C shows that the lithium manganate-based positive electrode active material has an average particle size of 6.6 μm and a submicron particle abundance ratio of 6% by weight.
図４に、実施例１と同様に正極合材、全固体リチウム二次電池を作製し充放電試験を行った結果を示す。図４から明らかな通り、初期充電容量は５２ｍＡｈ／ｇ、初期放電容量は４２ｍＡｈ／ｇであり、１０サイクル後の充電容量は３９ｍＡｈ／ｇで放電容量は３８ｍＡｈ／ｇであった。これら充放電特性データより、得られたマンガン酸リチウム系正極活物質は全固体リチウム二次電池において良好な充放電特性を示すことが明らかである。 FIG. 4 shows the results of producing a positive electrode mixture and an all-solid lithium secondary battery and conducting a charge / discharge test in the same manner as in Example 1. As apparent from FIG. 4, the initial charge capacity was 52 mAh / g, the initial discharge capacity was 42 mAh / g, the charge capacity after 10 cycles was 39 mAh / g, and the discharge capacity was 38 mAh / g. From these charge / discharge characteristic data, it is clear that the obtained lithium manganate-based positive electrode active material exhibits good charge / discharge characteristics in an all-solid lithium secondary battery.
比較例
実施例１と同様にシュウ酸マンガン２水和物０．１ｍｏｌ（１７．９０ｇ）を秤量し、電気炉にて大気中４００℃、５時間熱分解して、０．０５ｍｏｌのＭｎ2Ｏ3微粉末を作製した。得られた粉末に対し、水酸化リチウム１水和物を、Ｌｉ／Ｍｎ比０．５０（０．０１２５ｍｏｌ）になる量（０．５２５ｇ）加え、乾式法にて十分に混合した。混合物を５００ｋｇ／ｃｍ2で錠剤成形後、電気炉に入れ、大気中８５０℃、１０時間焼成し、目的
とするマンガン酸リチウム系粉末（Ｌｉ1.00Ｍｎ2.00Ｏ4）を得た。
Comparative Example In the same manner as in Example 1, 0.1 mol (17.90 g) of manganese oxalate dihydrate was weighed and thermally decomposed in an electric furnace at 400 ° C. in the atmosphere for 5 hours to obtain 0.05 mol of Mn 2 O. 3 fine powders were prepared. Lithium hydroxide monohydrate was added to the obtained powder in an amount (0.525 g) to give a Li / Mn ratio of 0.50 (0.0125 mol), and mixed well by a dry method. The mixture was tableted at 500 kg / cm 2 and then placed in an electric furnace and baked in the atmosphere at 850 ° C. for 10 hours to obtain the target lithium manganate powder (Li 1.00 Mn 2.00 O 4 ).
得られた試料のＸ線回折図形より、すべてのピークが From the X-ray diffraction pattern of the obtained sample, all the peaks are
図２に、この比較例で得られた粉末のＳＥＭ写真を示す。このＳＥＭ観察により、この粉末は、実施例１に比して、粒子径３μｍ以上の粗大粒子が認められるものの、１μｍ以下のサブミクロン粒子がかなり存在していることが確認できた。 FIG. 2 shows an SEM photograph of the powder obtained in this comparative example. From this SEM observation, it was confirmed that although this particle had coarse particles having a particle diameter of 3 μm or more as compared with Example 1, submicron particles of 1 μm or less were considerably present.
図３（ａ）に、得られた粉末の粒度分布を、実施例１と同様にして測定した結果を示す。図中、縦棒が各粒径での分率、黒丸が累積分布を示す。図３（ａ）より、平均粒径１．１μｍ、サブミクロン粒子存在比４２重量％と見積もられ、多量のサブミクロン粒子が存在していることが確認でき、正極としたときに充填性が不十分なため電解質との界面接触面積が小さくなることが予想される。 FIG. 3A shows the result of measuring the particle size distribution of the obtained powder in the same manner as in Example 1. In the figure, vertical bars indicate the fractions for each particle size, and black circles indicate the cumulative distribution. From FIG. 3 (a), it is estimated that the average particle size is 1.1 μm and the submicron particle abundance ratio is 42% by weight, and it can be confirmed that a large amount of submicron particles are present. Since it is insufficient, the interface contact area with the electrolyte is expected to be small.
図４に、実施例１と同様に正極合材、全固体リチウム二次電池を作製し充放電試験を行った結果を示す。図４から明らかな通り、初期充電容量は３７ｍＡｈ／ｇ、初期放電容量は１９ｍＡｈ／ｇであり、１０サイクル後の充電容量は１４ｍＡｈ／ｇで放電容量は１３ｍＡｈ／ｇであった。これは上記の実施例１及び２と比較して、正極の重量当たり挿入・脱離できるＬｉ量が多いにもかかわらず低容量しか得られておらず、得られたマンガン酸リチウム系正極活物質は、全固体リチウム二次電池において良好な充放電特性を示していないことが明らかである。 FIG. 4 shows the results of producing a positive electrode mixture and an all-solid lithium secondary battery and conducting a charge / discharge test in the same manner as in Example 1. As is apparent from FIG. 4, the initial charge capacity was 37 mAh / g, the initial discharge capacity was 19 mAh / g, the charge capacity after 10 cycles was 14 mAh / g, and the discharge capacity was 13 mAh / g. Compared with Examples 1 and 2 above, only a low capacity was obtained despite the large amount of Li that could be inserted and removed per weight of the positive electrode, and the obtained lithium manganate positive electrode active material Is clearly not showing good charge / discharge characteristics in an all-solid lithium secondary battery.
Claims (1)
Ｌｉ１＋ｘ（Ｍｎ２−ｙＭｙ）２−ｘＯ４ （Ｉ）
（式中、ＭはＡｌ、Ｍｇ、Ｃｒ、Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ又はＺｎを示す。ｘは、ＭがＭｎである場合は、０＜ｘ＜０．３３の範囲の数であり、ＭがＭｎ以外である場合は、０≦ｘ＜０．３３の範囲の数である。ｙは、０≦ｙ≦１の範囲の数である。）で表され、且つ１μｍ以下の粒子の存在比が４０重量％以下であるマンガン酸リチウム系正極活物質を含む硫化物系無機固体電解質を用いた全固体リチウム二次電池。 It has a cubic spinel structure and has the composition formula Li 1 + x (Mn 2−y M y ) 2−x O 4 (I)
(In the formula, M represents Al, Mg, Cr, Mn, Fe, Co, Ni, Cu, or Zn. When M is Mn, x is a number in the range of 0 <x <0.33. In the case where M is other than Mn, the number is in the range of 0 ≦ x <0.33. Y is the number in the range of 0 ≦ y ≦ 1, and the particle size is 1 μm or less. An all-solid lithium secondary battery using a sulfide-based inorganic solid electrolyte containing a lithium manganate-based positive electrode active material having an abundance ratio of 40% by weight or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004089498A JP4296274B2 (en) | 2004-03-25 | 2004-03-25 | Lithium manganate positive electrode active material and all-solid lithium secondary battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004089498A JP4296274B2 (en) | 2004-03-25 | 2004-03-25 | Lithium manganate positive electrode active material and all-solid lithium secondary battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2005276680A JP2005276680A (en) | 2005-10-06 |
| JP4296274B2 true JP4296274B2 (en) | 2009-07-15 |
Family
ID=35176106
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004089498A Expired - Lifetime JP4296274B2 (en) | 2004-03-25 | 2004-03-25 | Lithium manganate positive electrode active material and all-solid lithium secondary battery |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4296274B2 (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2890241B1 (en) * | 2005-08-25 | 2009-05-22 | Commissariat Energie Atomique | HIGH SPEED SPINELLE STRUCTURE POSITIVE ELECTRODE MATERIAL BASED ON NICKEL AND MANGANESE FOR LITHIUM ACCUMULATORS |
| JP5224081B2 (en) * | 2006-04-19 | 2013-07-03 | 株式会社Ｇｓユアサ | Nonaqueous electrolyte secondary battery |
| JP2008091328A (en) * | 2006-09-04 | 2008-04-17 | Sumitomo Electric Ind Ltd | Lithium secondary cell and its manufacturing method |
| EP2172996A4 (en) | 2007-07-19 | 2013-07-31 | Jx Nippon Mining & Metals Corp | Lithium-manganese double oxide for lithium ion batteries and process for the production of the double oxide |
| JP5300241B2 (en) * | 2007-10-29 | 2013-09-25 | 日産自動車株式会社 | Positive electrode for high-power lithium-ion battery |
| JP5344418B2 (en) * | 2008-01-10 | 2013-11-20 | 出光興産株式会社 | All-solid lithium secondary battery and method for producing the same |
| JP2010045019A (en) * | 2008-07-16 | 2010-02-25 | Tokyo Metropolitan Univ | All-solid lithium secondary battery, and method of manufacturing the same |
| US20120028128A1 (en) * | 2009-03-18 | 2012-02-02 | Santoku Corporation | All-solid-state lithium battery |
| JP5710136B2 (en) * | 2009-03-18 | 2015-04-30 | 出光興産株式会社 | All solid lithium battery |
| JP5752890B2 (en) * | 2009-03-18 | 2015-07-22 | 出光興産株式会社 | Positive electrode mixture and lithium battery |
| JPWO2011111555A1 (en) * | 2010-03-09 | 2013-06-27 | 株式会社村田製作所 | All-solid secondary battery and manufacturing method thereof |
| CN103187554A (en) * | 2011-12-28 | 2013-07-03 | 上海空间电源研究所 | Manganese-based composite electrode, lithium-ion battery containing manganese-based composite electrode, and preparation method |
| CN105186045B (en) * | 2015-11-02 | 2017-11-07 | 深圳市新浦自动化设备有限公司 | A kind of chemical synthesizing method of flexible packing lithium ion battery |
| CN113130979A (en) * | 2021-04-20 | 2021-07-16 | 清华大学深圳国际研究生院 | Solid electrolyte, preparation method thereof and solid battery |
-
2004
- 2004-03-25 JP JP2004089498A patent/JP4296274B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP2005276680A (en) | 2005-10-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6108249B2 (en) | Positive electrode active material, method for producing the same, and lithium secondary battery including the same | |
| JP5617417B2 (en) | Garnet-type lithium ion conductive oxide and process for producing the same | |
| CN110521034B (en) | Negative electrode material for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery | |
| US9640794B2 (en) | Lithium transition metal oxide having layered structure | |
| JP4406744B2 (en) | Cathode active material for non-aqueous secondary battery, method for producing the same, and non-aqueous secondary battery using the same | |
| CN110800149A (en) | Solid electrolyte for lithium secondary battery and sulfide-based compound for the solid electrolyte | |
| JP4096754B2 (en) | Cathode active material for non-aqueous electrolyte secondary battery | |
| US20110053000A1 (en) | Ceramic material and use thereof | |
| JP5846482B2 (en) | Sodium manganese titanium nickel composite oxide, method for producing the same, and sodium secondary battery using the same as a member | |
| KR102016788B1 (en) | Anode active material for sodium secondary battery, and manufacturing method therefor | |
| JP2005251716A (en) | Cathode active substance for nonaqueous electrolyte secondary battery, cathode mixture for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery | |
| JP2000277116A (en) | Lithium secondary battery | |
| JP4296274B2 (en) | Lithium manganate positive electrode active material and all-solid lithium secondary battery | |
| JP2004235144A (en) | Nonaqueous electrolyte secondary battery and negative electrode active substance therefor | |
| JP4258170B2 (en) | Positive electrode for secondary battery and secondary battery using the same | |
| JP2002279985A (en) | Positive electrode active material for non-aqueous lithium secondary battery and the non-aqueous lithium secondary battery using the active material | |
| EP4023603A1 (en) | Positive electrode active material for lithium ion secondary battery, and lithium ion secondary battery | |
| TWI574451B (en) | A positive electrode active material for a lithium ion battery, a positive electrode for a lithium ion battery, and a lithium ion battery | |
| KR20150030656A (en) | Lithium metal complex oxide | |
| JP2006318929A (en) | Cathode active substance for lithium secondary battery, and nonaqueous lithium secondary battery | |
| CN106463720A (en) | Positive electrode active substance particle powder for non-aqueous electrolyte secondary battery, production method therefor, and non-aqueous electrolyte secondary battery | |
| JPH09219215A (en) | Lithium ion battery | |
| JP4798962B2 (en) | Lithium manganese composite oxide and method for producing the same | |
| JP7315553B2 (en) | Positive electrode active material | |
| JP2000231919A (en) | Positive electrode active material and nonaqueous electrolyte secondary battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20051004 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080515 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080715 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080908 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090317 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |