WO2019188750A1 - Inspection method - Google Patents

Inspection method Download PDF

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WO2019188750A1
WO2019188750A1 PCT/JP2019/011995 JP2019011995W WO2019188750A1 WO 2019188750 A1 WO2019188750 A1 WO 2019188750A1 JP 2019011995 W JP2019011995 W JP 2019011995W WO 2019188750 A1 WO2019188750 A1 WO 2019188750A1
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atmosphere
sample
ionization potential
lithium secondary
secondary battery
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PCT/JP2019/011995
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French (fr)
Japanese (ja)
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手嶋　勝弥
信行 是津
山田　哲也
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国立大学法人信州大学
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Priority to KR1020207027760A priority Critical patent/KR102278258B1/en
Priority to JP2020509940A priority patent/JP6905292B2/en
Priority to CN201980022094.3A priority patent/CN111902977B/en
Publication of WO2019188750A1 publication Critical patent/WO2019188750A1/en

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/02—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/02—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material
    • G01N23/04—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material and forming images of the material
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/22—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material
    • G01N23/227—Measuring photoelectric effect, e.g. photoelectron emission microscopy [PEEM]
    • G01N23/2273—Measuring photoelectron spectrum, e.g. electron spectroscopy for chemical analysis [ESCA] or X-ray photoelectron spectroscopy [XPS]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0561—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of inorganic materials only
    • H01M10/0562—Solid materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • 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

Abstract

This inspection method is for inspecting, under atmospheric pressure, the condition of surface electrons of electrode materials or solid-state electrolyte materials for lithium secondary batteries. In this inspection method, the condition of surface electrons of an electrode material for lithium secondary batteries is inspected from the ionization potential specific to the electrode material for lithium secondary batteries or the solid-state electrolyte material.

Description

検査方法Inspection method
　本発明は、リチウム二次電池用材料の表面電子状態を検査する検査方法に関する。
本願は、２０１８年３月３０日に、日本に出願された特願２０１８－０６６４９５号に基づき優先権を主張し、その内容をここに援用する。 The present invention relates to an inspection method for inspecting a surface electronic state of a material for a lithium secondary battery.
This application claims priority on March 30, 2018 based on Japanese Patent Application No. 2018-066495 filed in Japan, the contents of which are incorporated herein by reference.
　リチウム二次電池は、既に携帯電話用途やノートパソコン用途などの小型電源として実用化されている。更に自動車用途や電力貯蔵用途などの中型、又は大型電源においても適用が試みられている。リチウム二次電池の性能の向上及び維持のため、リチウム二次電池自体又はその材料の性能を検査する方法についても、種々の検討がなされている。
　例えば特許文献１には、二次電池の内部短絡を検査する二次電池の検査方法が記載されている。 Lithium secondary batteries have already been put into practical use as small power sources for cellular phones and notebook computers. Furthermore, application is also attempted in medium-sized or large-sized power sources such as automobile applications and power storage applications. In order to improve and maintain the performance of the lithium secondary battery, various studies have been made on methods for inspecting the performance of the lithium secondary battery itself or its material.
For example, Patent Document 1 describes a secondary battery inspection method for inspecting an internal short circuit of a secondary battery.
特開２０１２－１０４２７６号公報JP 2012-104276 A
　リチウム二次電池には、電極活物質や固体電解質としてリチウム複合酸化物および非酸化物の粉末が使用されている。リチウム複合酸化物の表面は、大気に曝されると劣化する。劣化現象の例としては、大気中の水分と反応することにより、表面に抵抗層が形成される場合がある。このような劣化現象の発生は、リチウム二次電池の性能劣化の原因となる。その他、カチオンミキシングや格子欠陥などの生成により結晶構造が乱れる場合、電池性能が大幅に劣化する。
　このため、リチウム二次電池の原料として用いられるリチウム二次電池用材料の性能を、電池試験を行わなくても、短時間で正確に予測する検査方法が求められる。 Lithium secondary batteries use lithium composite oxides and non-oxide powders as electrode active materials and solid electrolytes. The surface of the lithium composite oxide deteriorates when exposed to the atmosphere. As an example of the deterioration phenomenon, a resistance layer may be formed on the surface by reacting with moisture in the atmosphere. Generation | occurrence | production of such a deterioration phenomenon causes the performance deterioration of a lithium secondary battery. In addition, when the crystal structure is disturbed due to generation of cation mixing or lattice defects, the battery performance is significantly deteriorated.
Therefore, there is a need for an inspection method that accurately predicts the performance of a lithium secondary battery material used as a raw material for a lithium secondary battery in a short time without performing a battery test.
　本発明は上記事情に鑑みてなされたものであって、リチウム二次電池材料の性能を左右する、原子層レベルから１０ｎｍ厚の表面抵抗層の生成や結晶構造の乱れなどの表面電子状態を短時間で正確に検査する方法を提供することを目的とする。これにより、リチウム二次電池の原料として用いられるリチウム二次電池用材料の性能を、電池試験を行わなくても、短時間で正確に予測できるようになる。 The present invention has been made in view of the above circumstances, and has a short effect on the surface electronic states such as generation of a surface resistance layer having a thickness of 10 nm from the atomic layer level and disorder of the crystal structure, which influence the performance of the lithium secondary battery material. The object is to provide a method for accurately checking in time. As a result, the performance of the material for the lithium secondary battery used as the raw material for the lithium secondary battery can be accurately predicted in a short time without performing a battery test.
　本発明は以下の［１］～［９］を包含する。
　本発明の第一の態様は、[１]に述べる検査方法を提供する。
［１］リチウム二次電池用電極材料または固体電解質材料の表面電子状態を大気圧下で検査する検査方法であって、前記リチウム二次電池用電極材料または前記固体電解質材料固有のイオン化ポテンシャルから、リチウム二次電池用電極材料の表面電子状態を検査する、検査工程を有する、検査方法。
　第一の態様の方法は、以下の特徴を好ましく含む。
［２］前記イオン化ポテンシャルを大気中紫外線光電子分光分析装置により測定する、［１］に記載の検査方法。
［３］前記検査工程が、大気中紫外線光電子分光分析装置を用いて、大気に曝した直後の、リチウム二次電池用電極材料または固体電解質材料の、イオン化ポテンシャルを測定する測定工程と、その後さらに前記リチウム二次電池用電極材料または固体電解質材料を大気に曝し、前記さらに大気に曝した材料のイオン化ポテンシャルを、前記装置を用いて測定する測定工程と、前記さらに大気に曝した材料について測定されたイオン化ポテンシャルが、大気に曝した直後のイオン化ポテンシャルよりも低下したかどうか、を判断する判断工程と、低下したと判断したときは、リチウム二次電池用電極材料の表面に劣化が見られたと判定する判定工程とを含む、［１］又は［２］に記載の検査方法。
　さらに本発明は、下記の態様を含む。
［４］前記大気に曝した直後の測定が、大気中に前記材料を曝してから０分間以上５分間以下の間に行われる、［３］に記載の検査方法。
［５］リチウム二次電池用電極材料または固体電解質材料を、第一の試料として用意する工程と、前記材料を、大気に曝した暴露時間を１回以上変えて１回以上の測定を行い、１つ以上のイオン化ポテンシャルの値を得る工程と、前記値を保管する工程と、第一の試料と同じ化学組成を有する化合物からなる第二の試料を用意する工程と、第二の試料のイオン化ポテンシャルを測定する工程と、前記第一の試料の保管された値と、第二の試料の測定された値を比較する工程と、比較の結果から、第二の試料の表面電子状態を判定する工程を含む、［１］に記載の検査方法。
［６］前記リチウム二次電池用電極材料または前記固体電解質材料を大気に曝してそのイオン化ポテンシャルを測定した測定結果と、前記大気に曝した材料のＳＴＥＭ－ＡＤＦ測定及びＥＥＬＳ測定の少なくとも１つの結果と、を比較する工程と、比較結果から、前記材料の表面電子状態を確定する工程と、を含む、［１］に記載の検査方法。
［７］大気に曝した第一の試料のイオン化ポテンシャルの値と、前記大気に曝した材料のＳＴＥＭ－ＡＤＦ測定及びＥＥＬＳ測定の少なくとも１つの結果と、を比較する工程と、比較結果から、前記材料の表面電子状態を確定する工程と、を含む、［５］に記載の検査方法。
［８］前記リチウム二次電池用電極材料または前記固体電解質材料を大気に曝してそのイオン化ポテンシャルを測定した測定結果と、前記材料を電池に用いて、放電容量を測定した測定結果と、を比較する工程と、比較結果から、前記材料の表面電子状態を確定する工程と、を含む、［１］に記載の検査方法。
［９］前記第二の試料が、別途保管しておいた材料であり、前記第一の試料の保管された値と、第二の試料の測定された値を比較する工程が、前記第二の試料が、電池の製造に使用可能か、又は使用不可能かを判断する工程である、［５］に記載の検査方法。 The present invention includes the following [1] to [9].
The first aspect of the present invention provides the inspection method described in [1].
[1] An inspection method for inspecting a surface electronic state of an electrode material for a lithium secondary battery or a solid electrolyte material under atmospheric pressure, from an ionization potential specific to the electrode material for the lithium secondary battery or the solid electrolyte material, An inspection method comprising an inspection step of inspecting a surface electronic state of an electrode material for a lithium secondary battery.
The method of the first aspect preferably includes the following features.
[2] The inspection method according to [1], wherein the ionization potential is measured by an atmospheric ultraviolet photoelectron spectrometer.
[3] A measuring step of measuring an ionization potential of an electrode material or a solid electrolyte material for a lithium secondary battery immediately after exposure to the atmosphere using an atmospheric ultraviolet photoelectron spectrometer, and then further The lithium secondary battery electrode material or solid electrolyte material is exposed to the atmosphere, and the ionization potential of the material exposed to the atmosphere is measured using the apparatus, and the material further exposed to the atmosphere is measured. When the ionization potential was judged to be lower than the ionization potential immediately after exposure to the atmosphere, and when it was judged that the ionization potential was lowered, the surface of the electrode material for the lithium secondary battery was deteriorated. The inspection method according to [1] or [2], including a determination step of determining.
Furthermore, the present invention includes the following aspects.
[4] The inspection method according to [3], wherein the measurement immediately after exposure to the atmosphere is performed between 0 minutes and 5 minutes after exposure of the material to the atmosphere.
[5] A step of preparing an electrode material or a solid electrolyte material for a lithium secondary battery as a first sample, and performing one or more measurements by changing the exposure time of the material to the atmosphere one or more times, Obtaining one or more ionization potential values, storing the values, preparing a second sample comprising a compound having the same chemical composition as the first sample, and ionizing the second sample The surface electronic state of the second sample is determined from the step of measuring the potential, the step of comparing the stored value of the first sample with the measured value of the second sample, and the comparison result. The inspection method according to [1], including a step.
[6] A measurement result of measuring the ionization potential of the lithium secondary battery electrode material or the solid electrolyte material exposed to the atmosphere, and at least one result of STEM-ADF measurement and EELS measurement of the material exposed to the atmosphere And a step of determining a surface electronic state of the material from the comparison result. The inspection method according to [1].
[7] A step of comparing the ionization potential value of the first sample exposed to the atmosphere with at least one result of the STEM-ADF measurement and the EELS measurement of the material exposed to the atmosphere. And a step of determining a surface electronic state of the material. The inspection method according to [5].
[8] Comparison between a measurement result obtained by measuring the ionization potential of the lithium secondary battery electrode material or the solid electrolyte material exposed to the atmosphere and a measurement result obtained by measuring the discharge capacity using the material in a battery. The inspection method according to [1], including a step of performing and a step of determining a surface electronic state of the material from a comparison result.
[9] The second sample is a separately stored material, and the step of comparing the stored value of the first sample with the measured value of the second sample includes the second sample. The inspection method according to [5], which is a step of determining whether or not the sample is usable for battery production.
　本発明によれば、リチウム二次電池に用いられるリチウム二次電池用材料、又は固体電解質材料の性能に密接に関わる表面電子状態を、短時間で正確に検査する方法を提供することができる。 According to the present invention, it is possible to provide a method for accurately inspecting a surface electronic state closely related to the performance of a material for a lithium secondary battery used for a lithium secondary battery or a solid electrolyte material in a short time.
ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を大気暴露した直後、およびその後所定時間ごとに測定した粉末Ｘ線回折測定結果を示す図である。LiNi 0.82 Co 0.15 Al 0.03 O 2 immediately after the particles exposed to the atmosphere, and is a diagram showing the subsequent powder X-ray diffraction measurement results measured at every predetermined time. ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を大気暴露した直後、およびその後所定時間ごとに測定したイオン化ポテンシャルの測定結果を示す図である。LiNi 0.82 Co 0.15 Al 0.03 O 2 immediately after the particles exposed to the atmosphere, and is a view showing the measurement results of the subsequent ionization potential measured every predetermined time. ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を３時間大気暴露した後に測定したＥＥＬＳ測定の結果を示す図である。Shows the results of LiNi 0.82 Co 0.15 Al 0.03 O 2 EELS measurements particles measured after 3 hours exposure to the atmosphere a. ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を３時間大気暴露した後に測定したＳＴＥＭ－ＡＤＦ観察の結果を示す図である。It is a graph showing the results of measured STEM-ADF observed after 3 hours exposure to air the LiNi 0.82 Co 0.15 Al 0.03 O 2 particles.
　以下に、本発明を実施するための好ましい例について詳細に説明する。以下の説明は、発明の趣旨をより良く理解させるために具体的に説明するものであり、特に指定のない限り、本発明を限定するものではない。本発明の範囲内において、特に制限の無い限り、必要に応じて、時間、回数、タイミング、数、量、材料、形状、位置、種類などを、変更、追加、及び／又は、省略することも可能である。
＜検査方法＞
　本発明は、リチウム二次電池用電極材料または固体電解質材料の表面電子状態を、大気下で検査する検査方法である。
　本発明は、リチウム二次電池用電極材料または固体電解質材料について、イオン化ポテンシャル測定を行う。本発明は、リチウム二次電池用電極材料または固体電解質材料の固有の、すなわち前記材料自身の、イオン化ポテンシャルが測定される。なお固有のイオン化ポテンシャルとは、例えば、大気に曝した時間が非常に短い条件での、イオン化ポテンシャルであってもよい。
　本発明によれば、電極や電解質などのリチウム二次電池材料について、特別な前処理等を実施することなく、大気下において比較的短い時間で、例えば１試料あたり５分間以内で、検査することができる。なお本発明において、大気圧下とは標準大気圧を意味してよいが、特殊な装置による減圧や加圧をされていない状態を意味してもよい。大気下とは、大気雰囲気下であることを意味してよい。 Below, the preferable example for implementing this invention is demonstrated in detail. The following description is given specifically for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified. Within the scope of the present invention, unless otherwise specified, the time, number of times, timing, number, amount, material, shape, position, type, etc. may be changed, added, and / or omitted as necessary. Is possible.
<Inspection method>
The present invention is an inspection method for inspecting the surface electronic state of an electrode material or a solid electrolyte material for a lithium secondary battery in the atmosphere.
In the present invention, ionization potential measurement is performed on an electrode material or a solid electrolyte material for a lithium secondary battery. In the present invention, the ionization potential inherent to the electrode material for a lithium secondary battery or the solid electrolyte material, that is, the material itself, is measured. The intrinsic ionization potential may be, for example, an ionization potential under a condition where the exposure time to the atmosphere is very short.
According to the present invention, lithium secondary battery materials such as electrodes and electrolytes are inspected in a relatively short time in the atmosphere, for example, within 5 minutes per sample, without any special pretreatment. Can do. In the present invention, “under atmospheric pressure” may mean standard atmospheric pressure, but may mean a state where no special apparatus is used for depressurization or pressurization. Under air may mean under atmospheric air.
　イオン化ポテンシャル測定は、大気中紫外線光電子分光分析装置により、測定することが好ましい。 The ionization potential is preferably measured with an atmospheric ultraviolet photoelectron spectrometer.
　本実施形態において、「リチウム二次電池用電極材料」とは、リチウム二次電池用正極活物質、リチウム二次電池用負極活物質が挙げられる。具体的な例としては、コバルト、ニッケル、マンガン、アルミニウムの群から選ばれる１種の元素と、リチウムとを主成分とする、リチウム複合金属酸化物が挙げられる。
　より具体的なリチウム複合金属酸化物の例を挙げれば、例えば、リチウムニッケルコバルトアルミニウム複合酸化物、リチウムニッケルマンガン複合酸化物等が挙げられる。
　本実施形態において、「固体電解質材料」とは、全固体電池の電解質材料に用いられる材料である。具体的な例としては、硫化物固体電解質、酸化物固体電解質、リチウム含有硫化物、リチウム含有金属酸化物、リチウム含有窒化物、リン酸リチウム等が挙げられる。
　前記電極材料や固体電解質材料の形状やサイズは特に限定されないが、粒子や塊であってもよい。 In the present embodiment, examples of the “electrode material for a lithium secondary battery” include a positive electrode active material for a lithium secondary battery and a negative electrode active material for a lithium secondary battery. As a specific example, a lithium composite metal oxide mainly containing one element selected from the group consisting of cobalt, nickel, manganese, and aluminum and lithium can be given.
More specific examples of lithium composite metal oxides include lithium nickel cobalt aluminum composite oxide and lithium nickel manganese composite oxide.
In the present embodiment, the “solid electrolyte material” is a material used for the electrolyte material of an all-solid battery. Specific examples include a sulfide solid electrolyte, an oxide solid electrolyte, a lithium-containing sulfide, a lithium-containing metal oxide, a lithium-containing nitride, and lithium phosphate.
The shape and size of the electrode material or solid electrolyte material are not particularly limited, but may be particles or lumps.
≪第１実施形態≫
　本実施形態の検査方法では、大気中紫外線光電子分光分析装置を用いて、リチウム二次電池用電極材料または固体電解質材料のイオン化ポテンシャルを測定する。例えば、大気に曝した直後の材料のイオン化ポテンシャルも予め測定しておき、測定されたイオン化ポテンシャルが、大気に曝した直後のイオン化ポテンシャルよりも低下しいているかどうかを比較し判断する。そして低下したときは、リチウム二次電池用電極材料の表面に劣化が見られたと判定する。本発明では、暴露時間の長さは、その都度任意に設定できる。例えば、１つのサンプルを用いて、継続して又は断続的に暴露を行い、所定の時間が経過するごとに、評価を行ってよい。あるいは同じ種類又は異なる種類のサンプルを１つ以上用意し、条件を変えて評価をしてもよい。またそれらのデータを保管して、比較に用いてもよい。例えば、予め、特定の化合物の製品について、暴露時間の長さが異なる場合の、イオン化ポテンシャルのデータを、予め参考のため測定及び保管しておいてもよい。その後に、劣化がないかどうか判断したい同じ種類の化合物の製品があるときに、この製品のイオン化ポテンシャルを測定し、保管しておいた前記データと比較してよい。
　具体的な例を挙げると、リチウム二次電池用電極材料または固体電解質材料を、第一の試料として用意し、前記材料を、大気に曝した暴露時間を１回以上変えて１回以上の測定を行い、１つ以上のイオン化ポテンシャルの値を得て、この値を保管しても良い。前記測定は、暴露した直後のみを測定してもよい。そして別途、第一の試料と同じ化学組成及び／又はその他の特徴を有する化合物からなる第二の試料を用意し、これのイオン化ポテンシャルを測定し、前記第一の試料の保管された値と、第二の試料の測定された値を比較し、その結果から、第二の試料の表面電子状態を判定してもよい。
　なお大気中紫外線光電子分光分析装置では、試料に紫外線のエネルギーを変えながら紫外線を照射する。測定に使用する紫外線のエネルギーの範囲は任意に選択できる。材料から放出された光電子の数は、大気中で電子計測が可能なオープンカウンターで測定される。これらにより、大気中でイオン化ポテンシャルを測定できる。 << First Embodiment >>
In the inspection method of the present embodiment, the ionization potential of the electrode material for a lithium secondary battery or the solid electrolyte material is measured using an atmospheric ultraviolet photoelectron spectrometer. For example, the ionization potential of the material immediately after exposure to the atmosphere is also measured in advance, and it is determined by comparing whether or not the measured ionization potential is lower than the ionization potential immediately after exposure to the atmosphere. And when it falls, it determines with deterioration having been seen on the surface of the electrode material for lithium secondary batteries. In the present invention, the length of the exposure time can be arbitrarily set each time. For example, the exposure may be performed continuously or intermittently using one sample, and the evaluation may be performed each time a predetermined time elapses. Alternatively, one or more samples of the same type or different types may be prepared, and evaluation may be performed by changing the conditions. These data may be stored and used for comparison. For example, ionization potential data for a specific compound product when the length of exposure time is different may be measured and stored in advance for reference. Thereafter, when there is a product of the same type of compound that it is desired to determine for degradation, the ionization potential of this product may be measured and compared to the stored data.
As a specific example, an electrode material or a solid electrolyte material for a lithium secondary battery is prepared as a first sample, and the material is exposed to the atmosphere for one or more times by changing the exposure time to one or more times. To obtain one or more ionization potential values and store these values. The measurement may be performed only immediately after exposure. Separately, preparing a second sample made of a compound having the same chemical composition and / or other characteristics as the first sample, measuring the ionization potential of the second sample, the stored value of the first sample, The measured values of the second sample may be compared, and the surface electronic state of the second sample may be determined from the result.
In the atmospheric ultraviolet photoelectron spectrometer, the sample is irradiated with ultraviolet rays while changing the energy of ultraviolet rays. The range of the ultraviolet energy used for the measurement can be arbitrarily selected. The number of photoelectrons emitted from the material is measured with an open counter capable of measuring electrons in the atmosphere. As a result, the ionization potential can be measured in the atmosphere.
　本実施形態においては、リチウム二次電池用電極材料または固体電解質材料を大気に曝した直後を０時間とする。そして、任意に設定される時間毎に、例えば１時間ごとに、イオン化ポテンシャル測定を実施する。測定前のリチウム二次電池用電極材料や固体電解質材料は、大気に触れないように、保管できる。
　０時間のイオン化ポテンシャルから、０．１ｅＶ以上増加した場合には、リチウム二次電池用電極材料または固体電解質材料の表面に劣化が見られた、と判定する。なお、大気に曝した直後とは、任意に選択される時間であってよい。例えば、大気中に取り出して、０分から１５分の間であってもよく、０分から１０分の間や、０分から５分や、０分から３分の間であってもよい。
　イオン化ポテンシャルを測定することにより、リチウム二次電池材料の表面に抵抗層が形成されているか否かなど、理想構造からの変化、特に電池特性に密接にかかわる表面電子状態変化を、短時間で判定することができる。
　本発明によれば、例えば、別途保管しておいた材料を、既に以前に測定され保管されていた同じ種類の材料のイオン化ポテンシャルのデータと比較して、保管されていた材料が、電池の製造に使用可能か、又は使用不可能かを容易に判断することができる。
　得られたイオン化ポテンシャルの結果は、下記に述べる第２実施形態での結果や、ＳＴＥＭ－ＡＤＦ測定やＥＥＬＳ測定の結果や、電池材料を実際に電池に用いて得られたた放電容量の結果などと組み合わせて、判断を行ってもよい。 In the present embodiment, the time immediately after exposing the electrode material for lithium secondary battery or the solid electrolyte material to the atmosphere is defined as 0 hour. And ionization potential measurement is implemented for every time set arbitrarily, for example for every hour. The electrode material for the lithium secondary battery and the solid electrolyte material before the measurement can be stored so as not to be exposed to the atmosphere.
When the ionization potential at 0 hour increases by 0.1 eV or more, it is determined that the surface of the electrode material for the lithium secondary battery or the solid electrolyte material has deteriorated. Note that “immediately after exposure to the atmosphere” may be an arbitrarily selected time. For example, it may be taken out into the atmosphere and may be from 0 minutes to 15 minutes, from 0 minutes to 10 minutes, from 0 minutes to 5 minutes, or from 0 minutes to 3 minutes.
By measuring the ionization potential, changes from the ideal structure, such as whether or not a resistance layer is formed on the surface of the lithium secondary battery material, especially surface electronic state changes that are closely related to battery characteristics, can be quickly determined. can do.
According to the present invention, for example, the separately stored material is compared with the ionization potential data of the same type of material that has been previously measured and stored, so that the stored material is It can be easily determined whether it can be used or not.
The results of the obtained ionization potential include the results of the second embodiment described below, the results of STEM-ADF measurement and EELS measurement, the results of the discharge capacity actually obtained by using the battery material for the battery, etc. Judgment may be made in combination.
≪第２実施形態≫
　本実施形態は、リチウム二次電池用電極材料を合成したとき、合成されたリチウム二次電池用電極材料のイオン化ポテンシャル測定を実施する。そして、測定されたイオン化ポテンシャルが、別途測定された同一組成の標準的なリチウム二次電池用電極材料のそれよりも増加したかどうかを、比較し判断する。そして増加したとき、何らかの変化の発生、例えば、カチオンミキシングが発生しているか否かなど、リチウム二次電池用電極材料の表面に結晶構造の乱れが見られた、と判定する検査方法である。例えば、同じ材料や材料組成を用いる一方で、製造条件や製造方法の条件を変えて得られた、複数の電池材料のイオン化ポテンシャル値を測定して比較してよい。また得られた材料に、さらに、第１実施のように、大気への暴露時間の違いによるイオン化ポテンシャル値の評価を行い、判断に使用しても良い。ＳＴＥＭ－ＡＤＦ測定やＥＥＬＳ測定の結果や、電池材料を実際に電池に用いて得られたた放電容量の結果などと組み合わせて、判断を行ってもよい。 << Second Embodiment >>
In the present embodiment, when a lithium secondary battery electrode material is synthesized, the ionization potential of the synthesized lithium secondary battery electrode material is measured. Then, a comparison is made to determine whether or not the measured ionization potential has increased more than that of a standard lithium secondary battery electrode material having the same composition and measured separately. And when it increases, it is an inspection method that determines that a disorder of the crystal structure is observed on the surface of the electrode material for a lithium secondary battery, such as occurrence of some change, for example, whether cation mixing has occurred. For example, while using the same material and material composition, the ionization potential values of a plurality of battery materials obtained by changing the manufacturing conditions and the manufacturing method conditions may be measured and compared. Further, as in the first embodiment, the obtained material may be evaluated for an ionization potential value according to a difference in exposure time to the atmosphere and used for judgment. The determination may be made in combination with the result of STEM-ADF measurement or EELS measurement, or the result of the discharge capacity actually obtained by using the battery material for the battery.
≪ＳＴＥＭ－ＡＤＦ、ＥＥＬＳ測定≫
　ＳＴＥＭ－ＡＤＦ測定と、ＥＥＬＳ測定は、第１実施形態や第２実施形態の測定と組み合わせて、使用しても良い。　ＳＴＥＭ－ＡＤＦ（Ａｎｎｕｌａｒ　Ｄａｒｋ　Ｆｉｅｌｄ　Ｓｃａｎｎｉｎｇ　Ｔｒａｎｓｍｉｓｓｉｏｎ　Ｅｌｅｃｔｒｏｎ　Ｍｉｃｒｏｓｃｏｐｅ）測定方法とは、以下のように実施してもよい。リチウム二次電池用電極材料を、ＣＰ（クロスセクションポリッシャー）や、ＦＩＢ（集束イオンビーム）等で、断面測定用に、薄膜加工する。そして、そのサンプルの断面を透過するように電子線をあて、散乱電子を測定し、その強度を像として表示する。また、ＥＥＬＳ測定は，同一のサンプル面内を透過する電子が、原子との相互作用によって失うエネルギーを測定する方法である。 ≪STEM-ADF, EELS measurement≫
The STEM-ADF measurement and the EELS measurement may be used in combination with the measurement of the first embodiment or the second embodiment. The STEM-ADF (Annual Dark Field Scanning Transmission Electron Microscope) measurement method may be performed as follows. The electrode material for a lithium secondary battery is processed into a thin film for cross-sectional measurement using CP (cross section polisher), FIB (focused ion beam), or the like. Then, an electron beam is applied so as to pass through the cross section of the sample, the scattered electrons are measured, and the intensity is displayed as an image. In addition, the EELS measurement is a method for measuring the energy that electrons passing through the same sample plane lose due to the interaction with atoms.
　上述の方法により得られた画像において、リチウム二次電池用電極材料または固体電解質材料の表面に、結晶構造に相当する格子縞が観察されない場合には、抵抗層が形成されている、と判定できる。 In the image obtained by the above-described method, if no lattice stripes corresponding to the crystal structure are observed on the surface of the electrode material for the lithium secondary battery or the solid electrolyte material, it can be determined that the resistance layer is formed.
　第１実施形態及び第２実施形態により得られる測定値と、ＳＴＥＭ－ＡＤＦ測定方法、及びはＥＥＬＳ測定のいずれか一方又は両方による表面観察結果とを組み合わせることにより、Ｘ線回折測定では検出することが困難な最表面層における電子状態変化を、イオン化ポテンシャル測定の結果から、より良く予測することができる。このようなデータ収集し、蓄積することにより、短時間の検査結果に基づいて、リチウム二次電池材料の表面電子状態を詳細に検査することができる。 Detecting in X-ray diffraction measurement by combining the measurement values obtained by the first embodiment and the second embodiment with the surface observation result by one or both of STEM-ADF measurement method and EELS measurement It is possible to better predict the change in the electronic state in the outermost surface layer, which is difficult to perform, from the result of ionization potential measurement. By collecting and accumulating such data, the surface electronic state of the lithium secondary battery material can be inspected in detail based on a short-time inspection result.
　以下、実施例により本発明をより具体的に説明するが、本発明は以下の実施例に限定されるものではない。 Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to the following examples.
（実施例１）：ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子表面の抵抗層生成による性能劣化予測
　共沈法で合成した前駆体と水酸化リチウムを反応させて合成したＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を大気暴露した。この直後、およびその後、所定時間ごとに、粉末Ｘ線回折測定と、イオン化ポテンシャル測定を実施した。
　得られたＸ線回折結果におけるピーク位置と相対強度の変化、およびイオン化ポテンシャル変化を調べた。 (Example 1): LiNi 0.82 Co 0.15 Al 0.03 O 2 Prediction of performance degradation due to generation of resistance layer on particle surface LiNi 0 synthesized by reacting a precursor synthesized by a coprecipitation method with lithium hydroxide .82 Co 0.15 Al 0.03 O 2 particles were exposed to air. Immediately after this and thereafter every predetermined time, powder X-ray diffraction measurement and ionization potential measurement were performed.
Changes in peak position and relative intensity, and changes in ionization potential in the obtained X-ray diffraction results were examined.
　イオン化ポテンシャル測定
　イオン化ポテンシャル変化は、大気中光電子分光装置(理研計器株式会社製，ＡＣ－３)を用いて測定した。前記大気中光電子分光装置は、大気中紫外線光電子分光分析装置である。具体的には、ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子の粉末試料１００ｍｇ程度を専用の試料台上に用意し、４．２－７．０ｅＶのエネルギー範囲で測定した。測定直前まで、サンプルは露点制御されたアルゴン雰囲気下および乾燥アルゴンガスを封入したパウチの中で保管した。試料は暴露処理や測定中のみ、大気暴露した。
　一つのサンプルの測定にかかる時間は５分以内であった。得られた結果について、エネルギーを横軸、規格化光電子収率の平方根を縦軸にプロットした。最小二乗法で得られた外挿直線とグランドレベルとの交点から、イオン化ポテンシャルとして見積もった。暴露直後と３時間経過後の試料の、イオン化ポテンシャルの結果を得られたイオン化ポテンシャルを横軸（単位：ｅＶ）、規格化強度を縦軸（図２中、「Ｃｏｕｎｔ（％）」と記載）として、図２に記載する。 Measurement of ionization potential Ionization potential change was measured using an atmospheric photoelectron spectrometer (AC-3, manufactured by Riken Keiki Co., Ltd.). The atmospheric photoelectron spectrometer is an atmospheric ultraviolet photoelectron spectrometer. Specifically, about 100 mg of a powder sample of LiNi 0.82 Co 0.15 Al 0.03 O 2 particles was prepared on a dedicated sample stage and measured in the energy range of 4.2 to 7.0 eV. Until immediately before the measurement, the sample was stored under a dew point-controlled argon atmosphere and in a pouch filled with dry argon gas. Samples were exposed to the atmosphere only during exposure processing and measurements.
The time taken to measure one sample was within 5 minutes. About the obtained result, energy was plotted on the horizontal axis and the square root of normalized photoelectron yield was plotted on the vertical axis. The ionization potential was estimated from the intersection of the extrapolated line obtained by the least square method and the ground level. The ionization potential obtained as a result of the ionization potential of the sample immediately after exposure and after 3 hours passed is the horizontal axis (unit: eV), and the normalized intensity is the vertical axis (described as “Count (%)” in FIG. 2). As shown in FIG.
　粉末Ｘ線回折測定
　一般に、ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２に代表されるリチウムニッケル含有複合酸化物では、層状岩塩型の結晶構造において、Ｘ線源としてＣｕ－Ｋα線を用いた粉末Ｘ線回折から得られる、（００３）面と（１０４）面に帰属する回折線ピーク強度の比が１．２以上である。
　このピーク強度の比から、結晶構造の乱れを判断した。カチオンミキシングが生じている場合、すなわち結晶構造が層状岩塩型から岩塩型に近づく場合、（００３）面に帰属するＸ線回折強度が小さくなる。従って、このピーク強度の比が大きいほど、乱れの少ない層状岩塩型構造であることを意味する。 Powder X-ray diffraction measurement Generally, in a lithium nickel-containing composite oxide represented by LiNi 0.82 Co 0.15 Al 0.03 O 2 , Cu—Kα rays are used as an X-ray source in a layered rock salt type crystal structure. The ratio of the diffraction line peak intensity attributed to the (003) plane and the (104) plane obtained from the powder X-ray diffraction used is 1.2 or more.
The disorder of the crystal structure was judged from this peak intensity ratio. When cation mixing occurs, that is, when the crystal structure approaches the rock salt type from the layered rock salt type, the X-ray diffraction intensity attributed to the (003) plane becomes small. Therefore, it means that the larger the ratio of the peak intensities is, the less the layered rock salt structure is.
　図１に、ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を、大気暴露した直後、およびその後、１時間ごとに５時間まで暴露をして測定した、粉末Ｘ線回折測定結果を示す。図１からも明らかなように、結果を示す線は重なっており、回折線の位置や、（００３）面と（１０４）面に帰属する回折線ピーク強度の比に、変化は見られなかった。粉末Ｘ線回折測定では変化を感知できなかった。 FIG. 1 shows the powder X-ray diffraction measurement results obtained by measuring LiNi 0.82 Co 0.15 Al 0.03 O 2 particles immediately after being exposed to the atmosphere and thereafter by exposing for 5 hours every hour. Show. As is clear from FIG. 1, the lines indicating the results overlap, and no change was observed in the position of the diffraction lines or the ratio of the diffraction line peak intensities belonging to the (003) plane and the (104) plane. . No changes could be detected by powder X-ray diffraction measurement.
　図２に、ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を、大気暴露した直後、およびその後所定時間ごとに測定した、イオン化ポテンシャル変化の測定結果を示す。
　図２からも明らかなように、大気暴露してから３時間経過後に、最小二乗法で得られた外挿直線とグランドレベルとの交点から、イオン化ポテンシャルが顕著に増加したことがわかる。 FIG. 2 shows the measurement result of the change in ionization potential, measured immediately after exposure of LiNi 0.82 Co 0.15 Al 0.03 O 2 particles to the atmosphere and every predetermined time thereafter.
As is clear from FIG. 2, it can be seen that the ionization potential significantly increased from the intersection of the extrapolated line obtained by the least square method and the ground level after 3 hours from exposure to the atmosphere.
　図３に、ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を３時間大気暴露した後に測定した、ＥＥＬＳ測定の結果を示す。図４に、ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を３時間大気暴露した後に測定した、ＳＴＥＭ－ＡＤＦ観察の結果を示す。これらにおいては、一つのサンプルの測定には、２日間以上の測定時間を要した。ＳＴＥＭ－ＡＤＦ観察写真から、格子縞とは異なる模様を有する層の形成が見られることから、表面層に異相の形成が示唆された。加えて、ＥＥＬＳスペクトルからは表面から１０ｎｍ程度の厚みの層において、Ｎｉ由来のピークのシフトが見られた。これは、表面層の岩塩層（抵抗層）の生成を示唆している。これらの結果は、イオン化ポテンシャルの測定結果と対応する。 FIG. 3 shows the result of EELS measurement measured after the LiNi 0.82 Co 0.15 Al 0.03 O 2 particles were exposed to the atmosphere for 3 hours. FIG. 4 shows the result of STEM-ADF observation, which was measured after LiNi 0.82 Co 0.15 Al 0.03 O 2 particles were exposed to the atmosphere for 3 hours. In these, measurement of one sample required measurement time of 2 days or more. From the STEM-ADF observation photograph, formation of a layer having a pattern different from the checkered pattern was observed, suggesting the formation of a different phase in the surface layer. In addition, from the EELS spectrum, a shift in Ni-derived peak was observed in a layer having a thickness of about 10 nm from the surface. This suggests the formation of a rock salt layer (resistance layer) in the surface layer. These results correspond to the measurement results of the ionization potential.
　大気未暴露及び大気暴露３時間後の上記ＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を、電極活物質とするＲ２０３２型ハーフセルを作製した。
　開回路電圧が安定した後、２５℃で正極に対する電流密度を、正極活物質重量に対して１０ｍＡｈ／ｇとして、４．３Ｖとなるまで充電し、その後３．０Ｖとなるまで放電した時の放電容量を測定する充放電試験を行い、初期放電容量を求めた。 An R2032 type half cell using the above LiNi 0.82 Co 0.15 Al 0.03 O 2 particles not exposed to the atmosphere and 3 hours after exposure to the atmosphere as an electrode active material was prepared.
After the open circuit voltage is stabilized, the current density with respect to the positive electrode is 10 mAh / g with respect to the weight of the positive electrode active material at 25 ° C., the battery is charged to 4.3 V, and then discharged to 3.0 V. A charge / discharge test for measuring the capacity was performed to determine the initial discharge capacity.
　その結果、大気未暴露のＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を正極活物質とする電池では、２００ｍＡｈ/gの初期容量が得られた。これに対して、大気暴露３時間後のＬｉＮｉ０．８２Ｃｏ０．１５Ａｌ０．０３Ｏ２粒子を正極活物質とする電池では、１８０ｍＡｈ/g以下まで低下することがわかった。当該活物質は共にリチウム占有率が９８%程度であるにもかかわらず、初期放電容量に差が生じた。この結果は、粒子表面に形成された抵抗層の有無の違いによるものと考えられる。 As a result, in the battery using LiNi 0.82 Co 0.15 Al 0.03 O 2 particles unexposed to the atmosphere as the positive electrode active material, an initial capacity of 200 mAh / g was obtained. On the other hand, in the battery using LiNi 0.82 Co 0.15 Al 0.03 O 2 particles after 3 hours exposure to the atmosphere as the positive electrode active material, it was found to be reduced to 180 mAh / g or less. Although both the active materials had a lithium occupancy rate of about 98%, there was a difference in initial discharge capacity. This result is considered to be due to the difference in the presence or absence of the resistance layer formed on the particle surface.
　以上のように、測定に２日間以上必要とするＳＴＥＭ－ＡＤＦ観察とＥＥＬＳ測定から予測される性能劣化を、イオン化ポテンシャル測定では測定時間５分以内に、予測可能であることがわかった。 As described above, it was found that the performance degradation predicted from the STEM-ADF observation and the EELS measurement required for the measurement for two days or more can be predicted within the measurement time of 5 minutes in the ionization potential measurement.
（実施例２）：ＬｉＣｏＯ２単結晶粒子表面のカチオンミキシングによる性能劣化予測
　異なる手法で合成した８つのＬｉＣｏＯ2単結晶粒子のイオン化ポテンシャルを、大気中光電子分光装置(理研計器株式会社製，ＡＣ－３ )を用いて測定した。単離したＬｉＣｏＯ2単結晶粒子の粉末試料１００ｍｇ程度を専用の試料台上に用意し、４．２－７．０ｅＶのエネルギー範囲で測定した。測定直前までサンプルは露点制御されたアルゴン雰囲気下および乾燥アルゴンガスを封入したパウチの中で保管した。測定中のみ大気暴露した。一つのサンプルの測定にかかる時間は５分以内であった。本発明の判定方法では、得られたイオン化ポテンシャル値の高低によって、判定を行うことができる。 (Example 2): LiCoO 2 the ionization potential of the synthesized eight LiCoO 2 single crystal grains in the single crystal grain surface different performance deterioration prediction by cation mixing techniques, atmospheric photoelectron spectrometer (Riken Keiki Co., AC- 3). About 100 mg of a powder sample of isolated LiCoO 2 single crystal particles was prepared on a dedicated sample stage and measured in the energy range of 4.2 to 7.0 eV. Until immediately before the measurement, the sample was stored in a dew point-controlled argon atmosphere and in a pouch filled with dry argon gas. Exposure to air only during measurement. The time taken to measure one sample was within 5 minutes. In the determination method of the present invention, the determination can be made based on the level of the obtained ionization potential value.
　得られた結果について、エネルギーを横軸、規格化光電子収率の平方根を縦軸にプロットした。最小二乗法で得られた外挿直線とグランドレベルとの交点から、イオン化ポテンシャルとして見積もった。
　表１に、８つのサンプルについて、イオン化ポテンシャルと初期放電容量を示す。
　具体的には、ＬｉＣｏＯ2単結晶粒子を電極活物質とするＲ２０３２型ハーフセルをそれぞれ８つ製造し、これらについて、開回路電圧が安定した後、２５℃で０．５Ｃとして、４．２となるまで充電し、その後２．８Ｖとなるまで１０Ｃとして放電した時の放電容量を測定する充放電試験を行った。表１には、初期放電容量と当該ＬｉＣｏＯ2粒子に対応するイオン化ポテンシャルを示す。 About the obtained result, energy was plotted on the horizontal axis and the square root of normalized photoelectron yield was plotted on the vertical axis. The ionization potential was estimated from the intersection of the extrapolated line obtained by the least square method and the ground level.
Table 1 shows the ionization potential and the initial discharge capacity for eight samples.
Specifically, eight R2032-type half cells each using LiCoO 2 single crystal particles as electrode active materials were manufactured, and after these, the open circuit voltage was stabilized, the temperature became 4.2 at 25 ° C. and 0.5 C. Then, a charge / discharge test was performed to measure the discharge capacity when discharged as 10C until 2.8V. Table 1 shows the initial discharge capacity and the ionization potential corresponding to the LiCoO 2 particles.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　８つのサンプルは、実施例１の実験と同様に、粒子の形態や組成、Ｘ線回折パターンは全て同じであった。それにもかかわらず、イオン化ポテンシャルが５．７５ｅＶ以下を有する、ＬｉＣｏＯ2単結晶粒子を正極活物質として正極に用いた二次電池のみ、１３０ｍＡｈ／ｇ以上の良好な初期放電容量を示した（サンプル１、３、５、７、８）。これらの物性値の違いはＬｉＣｏＯ2結晶粒子表面のカチオンミキシングが要因として考えられる。この結果から，本発明の優位性を顕著に示すことがわかる。
　以上のように、本発明によれば、リチウム二次電池の原料として用いられるリチウム二次電池用電極材料の性能を、短時間で正確に検査する方法を提供できる。 The eight samples had the same particle morphology, composition, and X-ray diffraction pattern as in the experiment of Example 1. Nevertheless, only the secondary battery using the LiCoO 2 single crystal particles as the positive electrode active material for the positive electrode having an ionization potential of 5.75 eV or less showed a good initial discharge capacity of 130 mAh / g or more (Sample 1). 3, 5, 7, 8). The difference in these physical property values can be attributed to cation mixing on the surface of the LiCoO 2 crystal particles. This result shows that the superiority of the present invention is remarkably exhibited.
As described above, according to the present invention, it is possible to provide a method for accurately inspecting the performance of an electrode material for a lithium secondary battery used as a raw material for a lithium secondary battery in a short time.

Claims (9)

  1. 　リチウム二次電池用電極材料または固体電解質材料の表面電子状態を大気圧下で検査する検査方法であって、
    　前記リチウム二次電池用電極材料または前記固体電解質材料固有のイオン化ポテンシャルから、リチウム二次電池用電極材料の表面電子状態を検査する、検査工程を有する、検査方法。     An inspection method for inspecting a surface electronic state of an electrode material or a solid electrolyte material for a lithium secondary battery under atmospheric pressure,
    An inspection method comprising an inspection step of inspecting a surface electronic state of an electrode material for a lithium secondary battery from an ionization potential specific to the electrode material for the lithium secondary battery or the solid electrolyte material.
  2. 　前記イオン化ポテンシャルを大気中紫外線光電子分光分析装置により測定する、請求項１に記載の検査方法。 The inspection method according to claim 1, wherein the ionization potential is measured by an atmospheric ultraviolet photoelectron spectrometer.
  3. 　前記検査工程が、
    　大気中紫外線光電子分光分析装置を用いて、大気に曝した直後の、リチウム二次電池用電極材料または固体電解質材料の、イオン化ポテンシャルを測定する測定工程と、
    　その後さらに前記リチウム二次電池用電極材料または固体電解質材料を大気に曝し、前記さらに大気に曝した材料のイオン化ポテンシャルを、前記装置を用いて測定する測定工程と、
    　前記さらに大気に曝した材料について測定されたイオン化ポテンシャルが、大気に曝した直後のイオン化ポテンシャルよりも低下したかどうか、を判断する判断工程と、
    　低下したと判断したときは、リチウム二次電池用電極材料の表面に劣化が見られたと判定する判定工程とを含む、請求項１又は２に記載の検査方法。     The inspection step is
    A measurement process for measuring the ionization potential of an electrode material or a solid electrolyte material for a lithium secondary battery immediately after exposure to the atmosphere using an atmospheric ultraviolet photoelectron spectrometer,
    Thereafter, the lithium secondary battery electrode material or the solid electrolyte material is exposed to the atmosphere, and the ionization potential of the material exposed to the atmosphere is further measured using the apparatus;
    A determination step of determining whether the ionization potential measured for the material exposed to the atmosphere is lower than the ionization potential immediately after exposure to the atmosphere;
    3. The inspection method according to claim 1, further comprising a determination step of determining that the surface of the electrode material for the lithium secondary battery has deteriorated when it is determined that the voltage has decreased.
  4. 　前記大気に曝した直後の測定が、大気中に前記材料を曝してから０分間以上５分間以下の間に行われる、請求項３に記載の検査方法。 4. The inspection method according to claim 3, wherein the measurement immediately after the exposure to the atmosphere is performed between 0 minutes and 5 minutes after the exposure of the material to the atmosphere.
  5. 　リチウム二次電池用電極材料または固体電解質材料を、第一の試料として用意する工程と、
    　前記材料を、大気に曝した暴露時間を１回以上変えて１回以上の測定を行い、１つ以上のイオン化ポテンシャルの値を得る工程と、
    　前記値を保管する工程と、
    　第一の試料と同じ化学組成を有する化合物からなる第二の試料を用意する工程と、
    　第二の試料のイオン化ポテンシャルを測定する工程と、
    　前記第一の試料の保管された値と、第二の試料の測定された値を比較する工程と、
    　比較の結果から、第二の試料の表面電子状態を判定する工程を含む、請求項１に記載の検査方法。     Preparing a lithium secondary battery electrode material or solid electrolyte material as a first sample;
    Changing the exposure time of the material to the atmosphere one or more times and performing one or more measurements to obtain one or more ionization potential values;
    Storing the value;
    Providing a second sample comprising a compound having the same chemical composition as the first sample;
    Measuring the ionization potential of the second sample;
    Comparing the stored value of the first sample with the measured value of the second sample;
    The inspection method according to claim 1, comprising a step of determining a surface electronic state of the second sample from the result of the comparison.
  6. 　前記リチウム二次電池用電極材料または前記固体電解質材料を大気に曝してそのイオン化ポテンシャルを測定した測定結果と、
    　前記大気に曝した材料のＳＴＥＭ－ＡＤＦ測定及びＥＥＬＳ測定の少なくとも１つの結果と、を比較する工程と、
    　比較結果から、前記材料の表面電子状態を確定する工程と、を含む、請求項１に記載の検査方法。     A measurement result of measuring the ionization potential of the lithium secondary battery electrode material or the solid electrolyte material exposed to the atmosphere;
    Comparing at least one result of STEM-ADF measurement and EELS measurement of the material exposed to the atmosphere;
    The method according to claim 1, further comprising: determining a surface electronic state of the material from the comparison result.
  7. 　大気に曝した第一の試料のイオン化ポテンシャルの値と、
    　前記大気に曝した材料のＳＴＥＭ－ＡＤＦ測定及びＥＥＬＳ測定の少なくとも１つの結果と、を比較する工程と、
    　比較結果から、前記材料の表面電子状態を確定する工程と、を含む、請求項５に記載の検査方法。     The value of the ionization potential of the first sample exposed to the atmosphere;
    Comparing at least one result of STEM-ADF measurement and EELS measurement of the material exposed to the atmosphere;
    The method according to claim 5, further comprising: determining a surface electronic state of the material from the comparison result.
  8. 　前記リチウム二次電池用電極材料または前記固体電解質材料を大気に曝してそのイオン化ポテンシャルを測定した測定結果と、
    　前記材料を電池に用いて、放電容量を測定した測定結果と、を比較する工程と、
    　比較結果から、前記材料の表面電子状態を確定する工程と、を含む、請求項１に記載の検査方法。     A measurement result of measuring the ionization potential of the lithium secondary battery electrode material or the solid electrolyte material exposed to the atmosphere;
    Using the material for a battery, comparing the measurement results of measuring discharge capacity,
    The method according to claim 1, further comprising: determining a surface electronic state of the material from the comparison result.
  9. 　前記第二の試料が、別途保管しておいた材料であり、
    　前記第一の試料の保管された値と、第二の試料の測定された値を比較する工程が、前記第二の試料が、電池の製造に使用可能か、又は使用不可能かを判断する工程である、請求項５に記載の検査方法。     The second sample is a separately stored material,
    The step of comparing the stored value of the first sample with the measured value of the second sample determines whether the second sample can be used for battery manufacture or not. The inspection method according to claim 5, which is a process.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002305028A (en) * 2001-04-04 2002-10-18 Nissan Motor Co Ltd Manufacturing method of solid polyelectrolytic battery and solid polyelectrolyte
JP2003257677A (en) * 2002-03-04 2003-09-12 Honda Motor Co Ltd Organic electroluminescence element and its manufacturing method
JP2004259650A (en) * 2003-02-27 2004-09-16 Kanegafuchi Chem Ind Co Ltd Magnesium secondary battery
US20100230632A1 (en) * 2005-09-20 2010-09-16 Virtic, Llc High energy battery materials
JP2015032425A (en) * 2013-08-01 2015-02-16 日立金属株式会社 Negative electrode active material and secondary battery using the same

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012104276A (en) 2010-11-08 2012-05-31 Toyota Motor Corp Method for inspecting secondary battery
JP6523113B2 (en) * 2015-09-14 2019-05-29 株式会社東芝 Electrode, non-aqueous electrolyte battery, battery pack, and automobile

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002305028A (en) * 2001-04-04 2002-10-18 Nissan Motor Co Ltd Manufacturing method of solid polyelectrolytic battery and solid polyelectrolyte
JP2003257677A (en) * 2002-03-04 2003-09-12 Honda Motor Co Ltd Organic electroluminescence element and its manufacturing method
JP2004259650A (en) * 2003-02-27 2004-09-16 Kanegafuchi Chem Ind Co Ltd Magnesium secondary battery
US20100230632A1 (en) * 2005-09-20 2010-09-16 Virtic, Llc High energy battery materials
JP2015032425A (en) * 2013-08-01 2015-02-16 日立金属株式会社 Negative electrode active material and secondary battery using the same

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