JPH0831418A - Manufacture of positive electrode material of lithium secondary battery and nickel acid lithium - Google Patents
Manufacture of positive electrode material of lithium secondary battery and nickel acid lithiumInfo
- Publication number
- JPH0831418A JPH0831418A JP6157400A JP15740094A JPH0831418A JP H0831418 A JPH0831418 A JP H0831418A JP 6157400 A JP6157400 A JP 6157400A JP 15740094 A JP15740094 A JP 15740094A JP H0831418 A JPH0831418 A JP H0831418A
- Authority
- JP
- Japan
- Prior art keywords
- lithium
- nickel
- nickel compound
- positive electrode
- secondary battery
- 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.)
- Granted
Links
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
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、ニッケル酸リチウムを
含むリチウム二次電池用正極材料とリチウム二次電池お
よび複合酸化物であるニッケル酸リチウムの製造方法に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive electrode material for lithium secondary batteries containing lithium nickelate, a lithium secondary battery and a method for producing lithium nickelate which is a composite oxide.
【０００２】[0002]
【従来の技術】六方晶系であるα−ＮａＦｅＯ2 型構造
を有するコバルト酸リチウム（以下、コバルト酸リチウ
ムと略すことがある。）は、酸素イオン最密充填層の垂
直方向にリチウムイオンとコバルトイオンとが交互に層
状に規則配列した構造を有する化合物である。その構造
故に層内のリチウムイオンの拡散が比較的容易であり、
リチウムイオンを電気化学的にドープ・脱ドープするこ
とが可能である。この性質を利用して、コバルト酸リチ
ウムは、既に一部の携帯用電話やビデオカメラの電源用
のリチウム二次電池の正極材料として実用化された。さ
らに、リチウム二次電池は、次世代の高性能小型二次電
池、将来的には電気自動車用電源、あるいはロ−ドレベ
リング用電力貯蔵装置として期待され、コバルト酸リチ
ウムは、リチウム二次電池の正極材料としての応用がさ
らに検討されている。 2. Description of the Related Art Lithium cobalt oxide having a hexagonal α-NaFeO 2 type structure (hereinafter sometimes abbreviated as lithium cobalt oxide) is composed of lithium ions and cobalt in the direction perpendicular to the closest packed layer of oxygen ions. It is a compound having a structure in which ions and ions are alternately arranged in layers. Due to its structure, diffusion of lithium ions in the layer is relatively easy,
It is possible to electrochemically dope / undope lithium ions. Utilizing this property, lithium cobalt oxide has already been put to practical use as a positive electrode material for lithium secondary batteries for power supplies of some mobile phones and video cameras. Furthermore, lithium secondary batteries are expected as next-generation high-performance small secondary batteries, power sources for electric vehicles, or power storage devices for road leveling in the future, and lithium cobalt oxide is a lithium secondary battery The application as a positive electrode material is further studied.
【０００３】これに対して、α−ＮａＦｅＯ2 型構造を
有するニッケル酸リチウム（以下、ニッケル酸リチウム
と略すことがある。）も、コバルト酸リチウムと同様の
性質を有する物質として知られており、原料コスト、資
源的豊富さの面で有利であるが、コバルト酸リチウムに
比べて合成が難しいため、コバルト酸リチウムを用いた
研究開発が主流になっている。On the other hand, lithium nickelate having an α-NaFeO 2 type structure (hereinafter sometimes abbreviated as lithium nickelate) is also known as a substance having the same properties as lithium cobaltate, Although it is advantageous in terms of raw material cost and abundance of resources, it is more difficult to synthesize than lithium cobalt oxide, so research and development using lithium cobalt oxide has become the mainstream.
【０００４】ニッケル酸リチウムの合成が難しい理由と
して、８００℃を越える高温で焼成するとリチウムイオ
ンとニッケルイオンとが不規則に配列した、いわゆる岩
塩型ドメイン（以下、岩塩ドメインということがあ
る。）が混入する割合が大きくなってしまう点が挙げら
れる。岩塩ドメインは充放電に寄与しないばかりか、ニ
ッケル酸リチウムからリチウムイオンが引き抜かれる際
の可逆的な構造変化を阻害する。したがって、岩塩ドメ
インが混入すると、二次電池は充分な放電容量を得られ
ないので好ましくない。The reason why it is difficult to synthesize lithium nickelate is that there is a so-called rock salt type domain (hereinafter sometimes referred to as rock salt domain) in which lithium ions and nickel ions are irregularly arranged when fired at a high temperature exceeding 800 ° C. There is a point that the ratio of mixing becomes large. The rock salt domain not only contributes to charge and discharge, but also inhibits reversible structural change when lithium ions are extracted from lithium nickelate. Therefore, if the rock salt domain is mixed, the secondary battery cannot obtain a sufficient discharge capacity, which is not preferable.
【０００５】これを避けるために８００℃以下の低温で
焼成すると、リチウムサイトにニッケルが入るタイプの
置換が起こり易くなることが知られている。これは原料
として用いる炭酸リチウム等のリチウム化合物の分解反
応および拡散が律速となり、結果的にリチウムの供給が
遅れるためであると考えられている。リチウムサイトに
ニッケルが存在するとリチウムイオンの拡散を阻害して
充放電特性に悪影響を与えるとされている。このような
場合、試料のＬｉ／Ｎｉ比は１よりも小さくなるが、こ
の値と初回の放電容量との関係が調べられており、Ｌｉ
／Ｎｉ比が大きいほど放電容量が大きくなると報告され
ている〔荒井ら、第33回電池討論会、講演番号1A11(199
2)〕。It is known that, in order to avoid this, firing at a low temperature of 800 ° C. or lower facilitates substitution of the type in which nickel enters the lithium site. It is considered that this is because the decomposition reaction and diffusion of a lithium compound such as lithium carbonate used as a raw material are rate-determining, and as a result, the supply of lithium is delayed. It is said that the presence of nickel at the lithium site hinders the diffusion of lithium ions and adversely affects the charge / discharge characteristics. In such a case, the Li / Ni ratio of the sample becomes smaller than 1, but the relationship between this value and the initial discharge capacity has been investigated, and
It has been reported that the larger the / Ni ratio, the larger the discharge capacity [Arai et al., 33rd Battery Symposium, Lecture No. 1A11 (199
2)].
【０００６】したがって、リチウム二次電池用正極材料
としての応用を考えた場合、充放電に寄与せず、可逆的
な充放電を阻害する岩塩ドメインを含まず、かつリチウ
ムイオンの拡散に悪影響を与えるリチウムサイトのニッ
ケル存在量の小さなニッケル酸リチウム、即ち層状構造
で化学量論組成のＬｉＮｉＯ2 を得ることが望ましい。Therefore, in consideration of application as a positive electrode material for a lithium secondary battery, it does not contribute to charge and discharge, does not contain rock salt domains that inhibit reversible charge and discharge, and adversely affects diffusion of lithium ions. It is desirable to obtain lithium nickelate having a small amount of nickel present at the lithium site, that is, LiNiO 2 having a layered structure and a stoichiometric composition.
【０００７】そのような試みとしては、例えばニッケル
酸リチウム生成反応に先立つリチウム化合物の分解の必
要がない酸化リチウムＬｉ2 ０〔N. Brongerら、Z. Ano
rg.Allg. Chem., 333, 188 (1964)〕および過酸化リチ
ウムＬｉ2 ０2 〔菅野ら、電気化学協会第60回大会、講
演番号1G20(1993)〕を用いた方法が知られている。しか
しながら、これらの方法は出発物質がいずれも入手が困
難で、かつ容易に空気中の炭酸ガスあるいは水分と反応
してしまうために空気中で取り扱えないという欠点を有
する。As such an attempt, for example, lithium oxide Li 2 0 [N. Bronger et al., Z. Ano, which does not require decomposition of a lithium compound prior to a reaction for producing lithium nickelate, has been proposed.
rg.Allg. Chem., 333, 188 (1964) ] and lithium peroxide Li 2 0 2 [Sugano et al, Electrochemical Society 60th Annual Meeting, methods using Lecture No. 1G20 (1993)] are known . However, these methods have drawbacks in that they cannot be handled in air because all the starting materials are difficult to obtain and easily react with carbon dioxide gas or moisture in the air.
【０００８】また、特開平２−４０８６１号公報には、
水酸化リチウムと酸化ニッケルとを粉末形態で混合し、
大気中６００℃から８００℃で焼成することによりＬｉ
y Ｎｉ2-y Ｏ2 （ｙは０．８４から１．２２の範囲）を
得る方法が開示されている。しかしながら、同公報によ
ればこの方法で得られたＬｉy Ｎｉ2-y Ｏ2 は充電最大
電圧Ｖmax ＝４．２５Ｖ、放電最小電圧Ｖmin ＝３Ｖ、
０．２ｍＡ／ｃｍ2 の定電流で充放電試験を行った場
合、充放電サイクルを繰り返すことにより容量が低下す
ることが記載されている。すなわち、公報記載の図か
ら、サイクル特性が良好ではなく、第３０回目の放電容
量は第５回目の約６０％にすぎないことがわかる。この
ようにリチウム二次電池用正極材料としての性能はいま
だ不充分であった。Further, Japanese Patent Laid-Open No. 2-40861 discloses that
Mixing lithium hydroxide and nickel oxide in powder form,
Li by firing in air at 600 ° C to 800 ° C
A method for obtaining y Ni 2-y O 2 (y is in the range of 0.84 to 1.22) is disclosed. However, according to the same publication, Li y Ni 2-y O 2 obtained by this method has a maximum charge voltage Vmax = 4.25 V, a minimum discharge voltage Vmin = 3 V,
It is described that when a charge / discharge test is performed at a constant current of 0.2 mA / cm 2, the capacity is reduced by repeating the charge / discharge cycle. That is, it can be seen from the drawings described in the publication that the cycle characteristics are not good and the discharge capacity at the 30th time is only about 60% at the 5th time. Thus, the performance as a positive electrode material for a lithium secondary battery was still insufficient.
【０００９】また、リチウム化合物として硝酸リチウム
を用い、炭酸ニッケルまたは水酸化ニッケルと粉末形態
で混合して酸素中７５０℃で１５時間焼成する方法によ
り、Ｖmax ＝４．２Ｖ、Ｖmin ＝２．５Ｖ、０．１７ｍ
Ａ／ｃｍ2 の定電流で充放電試験を行った場合に約１６
０ｍＡｈ／ｇの放電容量を示すニッケル酸リチウムが得
られたこと、および２回目以降の充放電のクーロン効率
Ｅが９９．３％と優れた値を示すことが報告されている
が、初回の効率については２回目以降よりもかなり低い
値であることはうかがえるものの具体的な報告はない
〔小槻ら、第33回電池討論会、講演番号1A07(1992)〕。Further, lithium nitrate was used as a lithium compound, mixed with nickel carbonate or nickel hydroxide in powder form, and baked in oxygen at 750 ° C. for 15 hours to obtain Vmax = 4.2V, Vmin = 2.5V, 0.17m
Approximately 16 when charged / discharged at constant current of A / cm 2.
It has been reported that lithium nickel oxide having a discharge capacity of 0 mAh / g was obtained and that the Coulombic efficiency E of the second and subsequent charging / discharging shows an excellent value of 99.3%. Although it can be seen that the value is significantly lower than the second and subsequent times, there is no specific report [Otsuki et al., 33rd Battery Symposium, Lecture No. 1A07 (1992)].
【００１０】また、水酸化ニッケル粉末を水酸化リチウ
ム水溶液に分散した後、スプレードライ法により水酸化
ニッケル粉末表面に水酸化リチウムを析出させた後、６
００℃で４時間空気中で焼成する方法が知られている
（J. R. Dahnら、Solid StateIonics, 44, 87(199
0)）。この方法では生成物が少量の水酸化リチウムと炭
酸リチウムを含有するため、水で洗浄する必要があると
されている。この洗浄工程でニッケル酸リチウムのリチ
ウムイオンの一部が水素イオンＨ+ で置換されてしまう
ために、さらに６００℃で１時間空気中で焼成して水素
イオンを水として除去しなければならない。このように
非常に複雑な工程であり、工業的に効率的な方法ではな
かった。以上のように、従来の合成法を用いてリチウム
二次電池に応用した際に優れた充放電特性を示すニッケ
ル酸リチウムを含む正極材料は未だ得られていなかっ
た。Further, after the nickel hydroxide powder is dispersed in a lithium hydroxide aqueous solution, lithium hydroxide is deposited on the surface of the nickel hydroxide powder by a spray drying method, and then 6
A method of firing in air at 00 ° C for 4 hours is known (JR Dahn et al. Solid State Ionics, 44, 87 (199).
0)). According to this method, since the product contains a small amount of lithium hydroxide and lithium carbonate, it is necessary to wash with water. In this washing step, some of the lithium ions of lithium nickelate are replaced with hydrogen ions H + , so the hydrogen ions must be removed as water by baking in air at 600 ° C. for 1 hour. As such, it is a very complicated process and not an industrially efficient method. As described above, a positive electrode material containing lithium nickel oxide that exhibits excellent charge / discharge characteristics when applied to a lithium secondary battery using the conventional synthesis method has not been obtained yet.
【００１１】[0011]
【発明が解決しようとする課題】本発明の目的は、優れ
た充放電特性をもつα−ＮａＦｅＯ2 型構造を有するニ
ッケル酸リチウムを含むリチウム二次電池正極材料とリ
チウム二次電池およびニッケル酸リチウムの製造方法を
提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a lithium secondary battery positive electrode material containing lithium nickelate having an α-NaFeO 2 type structure having excellent charge / discharge characteristics, a lithium secondary battery, and lithium nickelate. It is to provide a manufacturing method of.
【００１２】[0012]
【課題を解決するための手段】このような事情をみて、
本発明者らは鋭意検討を行なった結果、硝酸リチウム溶
液中にニッケル化合物を分散させた後乾燥することで両
者を混合し、その後焼成することにより得られたニッケ
ル酸リチウムをリチウム二次電池正極として使用する
と、初回の充放電において８０％以上のクーロン効率を
示すことを見出し、本発明を完成させるに至ったもので
ある。[Means for Solving the Problems] In view of such circumstances,
As a result of intensive investigations by the present inventors, the nickel compound is dispersed in a lithium nitrate solution and then dried to mix the two, and then the nickel nickel oxide obtained by firing is mixed with lithium nickel battery positive electrode. It has been found that when used as, a coulombic efficiency of 80% or more is exhibited in the first charge and discharge, and the present invention has been completed.
【００１３】すなわち、本発明は次に記す発明である。 （１）初回の充放電におけるクーロン効率が８０％以上
であることを特徴とするα−ＮａＦｅＯ2 型構造を有す
るニッケル酸リチウムを含むリチウム二次電池正極材
料。 （２）硝酸リチウム溶液中にニッケル化合物を分散させ
た後溶媒を揮散させ、硝酸リチウムとニッケル化合物と
の混合物（ただし、硝酸リチウムとニッケル化合物との
混合比が等モルの場合を除く。）を得て、酸素を含む雰
囲気下で該混合物を焼成することを特徴とする（１）記
載のニッケル酸リチウムの製造方法。 （３）硝酸リチウム溶液中にニッケル化合物を分散させ
た後溶媒を揮散させ、硝酸リチウムとニッケル化合物
〔ただし、ＮｉＣＯ3 ・ｗＨ2 Ｏ（式中、ｗ≧０）を除
く。〕との混合物を得て、酸素を含む雰囲気下で該混合
物を焼成することを特徴とする（１）記載のニッケル酸
リチウムの製造方法。 （４）リチウム金属、リチウム合金、またはリチウムイ
オンをドープ・脱ドープ可能な材料を含む負極と、リチ
ウムイオンをドープ・脱ドープ可能な材料を含む正極
と、液体または固体の電解質とを有するリチウム二次電
池において、該正極として（１）記載のリチウム二次電
池正極材料を用いることを特徴とするリチウム二次電
池。That is, the present invention is the invention described below. (1) A lithium secondary battery positive electrode material containing lithium nickelate having an α-NaFeO 2 type structure, which has a Coulombic efficiency of 80% or more in the first charge and discharge. (2) A nickel compound is dispersed in a lithium nitrate solution and then the solvent is volatilized to obtain a mixture of lithium nitrate and a nickel compound (except when the mixing ratio of lithium nitrate and nickel compound is equimolar). The method for producing lithium nickelate according to (1), characterized in that the mixture is obtained and calcined in an atmosphere containing oxygen. (3) Dispersing the nickel compound in the lithium nitrate solution and then volatilizing the solvent to remove lithium nitrate and the nickel compound [however, NiCO 3 · wH 2 O (where, w ≧ 0). ], And baking the mixture in an atmosphere containing oxygen, the method for producing lithium nickelate according to (1). (4) Lithium secondary battery having a negative electrode containing lithium metal, a lithium alloy, or a material capable of doping or dedoping lithium ions, a positive electrode containing a material capable of doping or dedoping lithium ions, and a liquid or solid electrolyte. In a secondary battery, a lithium secondary battery positive electrode material described in (1) is used as the positive electrode.
【００１４】以下、本発明のニッケル酸リチウムを含む
リチウム二次電池正極材料とリチウム二次電池およびニ
ッケル酸リチウムの製造方法について詳しく説明する。
ここで、充放電のクーロン効率Ｅは次式で定義される。 Ｅ＝（放電電気量）／（充電電気量）×１００（％） ＝（放電電流×放電時間）／（充電電流×充電時間）×
１００（％）The lithium secondary battery positive electrode positive electrode material containing lithium nickel oxide, the lithium secondary battery and the method for producing lithium nickel oxide of the present invention will be described in detail below.
Here, the charge / discharge Coulombic efficiency E is defined by the following equation. E = (discharged electricity amount) / (charged electricity amount) × 100 (%) = (discharge current × discharge time) / (charge current × charge time) ×
100 (%)
【００１５】リチウム二次電池用正極材料としてニッケ
ル酸リチウムを用いた場合、初回の充放電のクーロン効
率が１００％を大きく下回る、即ち、いわゆる不可逆容
量が存在することが問題であり、従来は初回の充放電の
クーロン効率が８０％以上のものは得られていなかっ
た。When lithium nickel oxide is used as a positive electrode material for a lithium secondary battery, the problem is that the Coulomb efficiency of the first charge / discharge is much lower than 100%, that is, there is a so-called irreversible capacity, and conventionally, the first time. No charging / discharging Coulomb efficiency of 80% or more was obtained.
【００１６】本発明のニッケル酸リチウムを含む正極材
料は、初回の充放電におけるクーロン効率が８０％以上
であり、好ましくは８５％以上のものである。さらに、
本発明のニッケル酸リチウムを含む正極材料は、２回目
以降の効率は９９％以上を示し、サイクル劣化も小さい
という特徴を有する。The positive electrode material containing lithium nickel oxide according to the present invention has a Coulombic efficiency of 80% or more, preferably 85% or more in the first charge / discharge. further,
The positive electrode material containing lithium nickel oxide according to the present invention is characterized in that the efficiency after the second time is 99% or more and the cycle deterioration is small.
【００１７】次に、本発明におけるニッケル酸リチウム
の製造方法を説明する。原料として用いる硝酸リチウム
は高純度であることが好ましい。いったん溶液としてか
ら混合を行うため、粒径については特に制限はない。Next, the method for producing lithium nickelate according to the present invention will be described. The lithium nitrate used as a raw material is preferably highly pure. Since the solution is once mixed, the particle size is not particularly limited.
【００１８】硝酸リチウムを溶解させる溶媒としては、
水、エタノール等のアルコール類が挙げられる。特に水
が好ましい。しかしながら、これらに限定されるもので
はなく、硝酸リチウムを溶解するその他の有機溶媒を使
用することもできる。溶媒中に炭酸ガスが溶存している
と難溶性の炭酸リチウムを生成する可能性があるため、
硝酸リチウム溶液の調製に先だって脱炭酸操作を行うこ
とがより好ましいが、不可欠な操作ではない。As a solvent for dissolving lithium nitrate,
Examples include water and alcohols such as ethanol. Water is particularly preferable. However, the present invention is not limited to these, and other organic solvents that dissolve lithium nitrate can also be used. When carbon dioxide gas is dissolved in the solvent, it may form sparingly soluble lithium carbonate.
It is more preferable to perform a decarboxylation operation prior to the preparation of the lithium nitrate solution, but it is not an essential operation.
【００１９】硝酸リチウム溶液中に分散させるニッケル
化合物としては、酸化ニッケル、水酸化ニッケル、炭酸
ニッケルＮｉＣＯ3 ・ｗＨ2 Ｏ（式中、ｗ≧０）、塩基
性炭酸ニッケルｘＮｉＣＯ3 ・ｙＮｉ（ＯＨ）2 ・ｚＨ
2 Ｏ（式中、ｘ＞０、ｙ＞０、ｚ＞０）、または酸性炭
酸ニッケルＮｉm Ｈ2n（ＣＯ3 ）m+n （式中、ｍ＞０、
ｎ＞０）などが挙げられる。酸化ニッケルとしては、一
酸化ニッケル（ＮｉＯ）、三酸化二ニッケル（Ｎｉ 2 Ｏ
3 ）、四酸化三ニッケル（Ｎｉ3 Ｏ4 ）が挙げられる。
なお、三酸化二ニッケル、四酸化三ニッケルについては
水化物も含む。塩基性炭酸ニッケルとしては、ＮｉＣＯ
3 ・２Ｎｉ（ＯＨ）2 ・４Ｈ2 Ｏ、２ＮｉＣＯ3 ・３Ｎ
ｉ（ＯＨ）2 ・４Ｈ2 Ｏ等が挙げられる。これらの中
で、塩基性炭酸ニッケルは一般に比表面積が大きく、工
業原料として安価で入手が容易であるため本発明で使用
するニッケル化合物として好ましい。Nickel dispersed in a lithium nitrate solution
Compounds include nickel oxide, nickel hydroxide, carbonic acid
Nickel NiCO3・ WH2O (in the formula, w ≧ 0), base
Nickel Carbonate x NiCO3・ YNi (OH)2・ ZH
2O (where x> 0, y> 0, z> 0) or acidic carbon
Nickel acid salt NimH2n(CO3)m + n(Where m> 0,
n> 0) and the like. As nickel oxide,
Nickel oxide (NiO), dinickel trioxide (Ni 2O
3), Tri-nickel tetroxide (Ni3OFour).
For dinickel trioxide and trinickel tetraoxide,
Including hydrates. As basic nickel carbonate, NiCO
3・ 2Ni (OH)2・ 4H2O, 2NiCO3・ 3N
i (OH)2・ 4H2O etc. are mentioned. Among these
In general, basic nickel carbonate has a large specific surface area,
Used in the present invention because it is cheap and easy to obtain as industrial raw material
Is preferable as the nickel compound.
【００２０】使用されるニッケル化合物は高純度である
ことが好ましい。また、分散性とその表面に硝酸リチウ
ムを析出させることを考慮すると、使用されるニッケル
化合物の平均粒径は、好ましくは１００μm 以下であ
り、さらに好ましくは５０μm以下である。比表面積と
しては、１ｍ2 ／ｇ以上のニッケル化合物を用いること
が好ましい。硝酸リチウム溶液にニッケル化合物を分散
させる場合、ニッケル化合物を真空容器に入れ真空にし
た後、硝酸リチウム溶液を添加し真空含浸することが好
ましい。ニッケル化合物の細孔部まで硝酸リチウム溶液
が浸透し、より均一に混合することができる。このよう
にして焼成して得られるニッケル酸リチウムは、真空含
浸を行わないものに比べて放電容量に変化はないが、試
料間の放電容量のバラツキが低減される。The nickel compound used is preferably of high purity. In consideration of dispersibility and precipitation of lithium nitrate on the surface, the average particle size of the nickel compound used is preferably 100 μm or less, more preferably 50 μm or less. A nickel compound having a specific surface area of 1 m 2 / g or more is preferably used. When the nickel compound is dispersed in the lithium nitrate solution, it is preferable that the nickel compound is placed in a vacuum container and evacuated, and then the lithium nitrate solution is added to carry out vacuum impregnation. The lithium nitrate solution penetrates into the pores of the nickel compound, and can be mixed more uniformly. The lithium nickelate obtained by firing in this manner has no change in discharge capacity as compared with the one not vacuum impregnated, but the variation in discharge capacity between samples is reduced.
【００２１】硝酸リチウムとニッケル化合物との混合比
は、Ｌｉ／Ｎｉ＝１の化学量論組成比で行うことができ
るが、１．０≦Ｌｉ／Ｎｉ≦１．１の範囲が好ましい。
この比が１．０未満では、得られた複合酸化物がリチウ
ム不足になるので好ましくない。混合状態に多少のバラ
ツキすなわち微視的な組成の分布が存在する可能性を考
慮すると、１．０＜Ｌｉ／Ｎｉ≦１．１の範囲がより好
ましく、１．００５≦Ｌｉ／Ｎｉ≦１．１の範囲がさら
に好ましい。また、この比が１．１を超えると、未反応
のリチウム成分が焼成後空気中で取り扱う際に炭酸リチ
ウムとなって試料中に残留してしまう割合が大きくな
り、放電容量を低下させるので好ましくない。The lithium nitrate and nickel compound can be mixed at a stoichiometric composition ratio of Li / Ni = 1, but preferably in the range of 1.0 ≦ Li / Ni ≦ 1.1.
If this ratio is less than 1.0, the obtained composite oxide becomes insufficient in lithium, which is not preferable. Considering the possibility that there is some variation in the mixed state, that is, there is a microscopic composition distribution, the range of 1.0 <Li / Ni ≦ 1.1 is more preferable, and 1.005 ≦ Li / Ni ≦ 1. The range of 1 is more preferable. If this ratio exceeds 1.1, the proportion of unreacted lithium component that becomes lithium carbonate and remains in the sample when handled in air after firing increases the discharge capacity, which is preferable. Absent.
【００２２】ニッケル化合物を分散させた硝酸リチウム
溶液から溶媒を揮散させるには、ロータリーエバポレー
ター、スプレードライヤーを用いることができる。ある
いは乾燥、焼成を同時に行うスプレードライヤーと縦型
焼成炉を組み合わせた、いわゆる噴霧熱分解装置を使用
することができる。A rotary evaporator and a spray dryer can be used to volatilize the solvent from the lithium nitrate solution in which the nickel compound is dispersed. Alternatively, it is possible to use a so-called spray pyrolyzer, which is a combination of a spray dryer for simultaneously drying and firing and a vertical firing furnace.
【００２３】焼成雰囲気としては酸素を含む雰囲気であ
る。具体的には、不活性ガスと酸素との混合気体、空気
等の酸素を含む雰囲気を挙げることができる。焼成雰囲
気の酸素分圧は高い方が好ましい。焼成は、好ましくは
酸素中で、より好ましくは酸素気流中で行われる。ま
た、焼成前に硝酸リチウムとニッケル化合物の混合粉末
を、硝酸リチウムの融点未満の温度で乾燥させることが
好ましい。硝酸リチウムの融点以上で乾燥を行うと相分
離を起こす可能性があるため好ましくない。このように
して焼成して得られるニッケル酸リチウムの放電容量
は、乾燥させないものに比べて変化はないが、試料間の
放電容量のバラツキが低減される。The firing atmosphere is an atmosphere containing oxygen. Specifically, a mixed gas of an inert gas and oxygen and an atmosphere containing oxygen such as air can be given. The oxygen partial pressure in the firing atmosphere is preferably high. Calcination is preferably carried out in oxygen, more preferably in a stream of oxygen. Further, it is preferable to dry the mixed powder of lithium nitrate and nickel compound at a temperature lower than the melting point of lithium nitrate before firing. Drying above the melting point of lithium nitrate may cause phase separation, which is not preferable. Although the discharge capacity of lithium nickel oxide obtained by firing in this way is not different from that of the case where it is not dried, variations in discharge capacity between samples are reduced.
【００２４】焼成温度は３５０℃以上８００℃以下が好
ましい。さらに好ましくは６００℃以上７５０℃以下で
ある。焼成温度が８００℃を超えると、岩塩ドメインの
混入割合が大きくなるので好ましくない。また、焼成温
度が３５０℃未満であるとニッケル酸リチウムの生成反
応がほとんど進行しないため好ましくない。焼成時間
は、２時間以上が好ましく、５時間以上がさらに好まし
い。The firing temperature is preferably 350 ° C. or higher and 800 ° C. or lower. More preferably, it is 600 ° C. or higher and 750 ° C. or lower. If the firing temperature exceeds 800 ° C., the mixing ratio of rock salt domains increases, which is not preferable. Further, if the firing temperature is lower than 350 ° C., the reaction for producing lithium nickelate hardly proceeds, which is not preferable. The firing time is preferably 2 hours or longer, more preferably 5 hours or longer.
【００２５】本発明の製造方法においては、焼成後のニ
ッケル酸リチウム粉末の洗浄操作は特に必要とはされな
いが、洗浄およびその後の熱処理、あるいは単独の熱処
理工程を必要に応じて付加することもできる。In the production method of the present invention, the washing operation of the lithium nickelate powder after firing is not particularly required, but washing and subsequent heat treatment, or a single heat treatment step can be added as necessary. .
【００２６】次に本発明のリチウム二次電池について詳
細に説明する。本発明のリチウム二次電池の正極は、前
述した本発明のニッケル酸リチウムを含むリチウム二次
電池正極材料を用いる。該正極は、具体的には、該ニッ
ケル酸リチウム、導電材としての炭素質材料、バインダ
ーとしての熱可塑性樹脂などを含有するものが挙げられ
る。炭素質材料としては、天然黒鉛、人造黒鉛、コーク
ス類などが挙げられる。熱可塑性樹脂としては、ポリフ
ッ化ビニリデン、ポリテトラフルオロエチレン、ポリエ
チレン、ポリプロピレンなどが挙げられる。Next, the lithium secondary battery of the present invention will be described in detail. The positive electrode of the lithium secondary battery of the present invention uses the lithium secondary battery positive electrode material containing the lithium nickel oxide of the present invention described above. Specific examples of the positive electrode include those containing the lithium nickel oxide, a carbonaceous material as a conductive material, and a thermoplastic resin as a binder. Examples of the carbonaceous material include natural graphite, artificial graphite, cokes and the like. Examples of the thermoplastic resin include polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene and the like.
【００２７】本発明のリチウム二次電池の負極として
は、リチウム金属、リチウム合金、またはリチウムイオ
ンをドープ・脱ドープ可能な材料が用いられる。リチウ
ムイオンをドープ・脱ドープ可能な材料としては、天然
黒鉛、人造黒鉛、コークス類、カーボンブラック、熱分
解炭素類、炭素繊維、有機高分子化合物焼成体などの炭
素質材料が挙げられる。炭素質材料の形状は薄片状、球
状、繊維状、または微粉末の凝集体などのいずれでもよ
く、必要に応じてバインダーとしての熱可塑性樹脂を添
加することができる。熱可塑性樹脂としては、ポリフッ
化ビニリデン、ポリエチレン、ポリプロピレンなどが挙
げられる。As the negative electrode of the lithium secondary battery of the present invention, a lithium metal, a lithium alloy, or a material capable of being doped / dedoped with lithium ions is used. Examples of the material capable of doping / dedoping with lithium ions include carbonaceous materials such as natural graphite, artificial graphite, cokes, carbon black, pyrolytic carbons, carbon fibers, and organic polymer compound fired bodies. The carbonaceous material may be in the form of flakes, spheres, fibers, or an aggregate of fine powder, and a thermoplastic resin as a binder may be added if necessary. Examples of the thermoplastic resin include polyvinylidene fluoride, polyethylene, polypropylene and the like.
【００２８】本発明のリチウム二次電池の電解質として
は、リチウム塩を有機溶媒に溶解させた非水電解質溶
液、または固体電解質のいずれかから選ばれる公知のも
のが用いられる。リチウム塩としては、ＬｉＣｌＯ4 、
ＬｉＰＦ6 、ＬｉＡｓＦ6 、ＬｉＳｂＦ6 、ＬｉＢ
Ｆ4 、ＬｉＣＦ3 ＳＯ3 、ＬｉＮ（ＣＦ3 ＳＯ2 ）2 、
Ｌｉ 2 Ｂ10Ｃｌ10、低級脂肪族カルボン酸リチウム塩、
ＬｉＡｌＣｌ4 などのうち一種あるいは二種以上の混合
物が挙げられる。As the electrolyte of the lithium secondary battery of the present invention
Is a non-aqueous electrolyte solution prepared by dissolving a lithium salt in an organic solvent.
A well-known material selected from either liquid or solid electrolytes
Is used. As the lithium salt, LiClOFour,
LiPF6, LiAsF6, LiSbF6, LiB
FFour, LiCF3SO3, LiN (CF3SO2)2,
Li 2BTenClTen, Lower aliphatic carboxylic acid lithium salt,
LiAlClFourOr a mixture of two or more
Things can be mentioned.
【００２９】有機溶媒としてはプロピレンカーボネー
ト、エチレンカーボネート、ジメチルカーボネート、ジ
エチルカーボネートなどのカーボネート類；１，２−ジ
メトキシエタン、１，３−ジメトキシプロパン、テトラ
ヒドロフラン、２−メチルテトラヒドロフランなどのエ
ーテル類；ギ酸メチル、酢酸メチル、γ−ブチロラクト
ンなどのエステル類；アセトニトリル、ブチロニトリル
などのニトリル類；Ｎ，Ｎ−ジメチルホルムアミド、
Ｎ，Ｎ−ジメチルアセトアミドなどのアミド類；３−メ
チル−２−オキサゾリドンなどのカーバメート類；スル
ホラン、ジメチルスルホキシド、１，３−プロパンサル
トンなどの含硫黄化合物が挙げられるが、通常はこれら
のうちの二種以上を混合して用いる。中でもカーボネー
ト類を含む混合溶媒が好ましく、環状カーボネートと非
環状カーボネート、または環状カーボネートとエーテル
類の混合溶媒がさらに好ましい。As the organic solvent, carbonates such as propylene carbonate, ethylene carbonate, dimethyl carbonate and diethyl carbonate; ethers such as 1,2-dimethoxyethane, 1,3-dimethoxypropane, tetrahydrofuran and 2-methyltetrahydrofuran; methyl formate , Esters such as methyl acetate and γ-butyrolactone; nitriles such as acetonitrile and butyronitrile; N, N-dimethylformamide,
Amides such as N, N-dimethylacetamide; carbamates such as 3-methyl-2-oxazolidone; sulfur-containing compounds such as sulfolane, dimethylsulfoxide, and 1,3-propanesultone, but of these, usually Two or more of these are mixed and used. Among them, a mixed solvent containing a carbonate is preferable, and a mixed solvent of a cyclic carbonate and an acyclic carbonate, or a mixed solvent of a cyclic carbonate and an ether is more preferable.
【００３０】固体電解質としてはポリエチレンオキサイ
ド系、ポリオルガノシロキサン鎖もしくはポリオキシア
ルキレン鎖の少なくとも一種以上を含む高分子化合物な
どの高分子電解質、またはＬｉ2 Ｓ−ＳｉＳ2 、Ｌｉ2
Ｓ−ＧｅＳ2 、Ｌｉ2 Ｓ−Ｐ 2 Ｓ5 、Ｌｉ2 Ｓ−Ｂ2 Ｓ
3 などの硫化物系電解質、またはＬｉ2 Ｓ−ＳｉＳ2−
Ｌｉ3 ＰＯ4 、Ｌｉ2 Ｓ−ＳｉＳ2 −Ｌｉ2 ＳＯ4 など
の硫化物を含む無機化合物系電解質が挙げられる。ま
た、高分子に非水電解質溶液を保持させた、いわゆるゲ
ルタイプのものを用いることもできる。なお、本発明の
リチウム二次電池の形状は特に限定されず、ペーパー
型、コイン型、円筒型、角型などのいずれであってもよ
い。Polyethylene oxide as the solid electrolyte
De-based, polyorganosiloxane chain or polyoxya
A polymer compound containing at least one or more alkylene chains
Which polyelectrolyte, or Li2S-SiS2, Li2
S-GeS2, Li2SP 2SFive, Li2S-B2S
3Sulfide-based electrolyte such as, or Li2S-SiS2−
Li3POFour, Li2S-SiS2-Li2SOFourSuch
Inorganic compound-based electrolytes containing sulfides of Well
In addition, a so-called gel in which a non-aqueous electrolyte solution is held in a polymer is used.
It is also possible to use the red type. In addition, according to the present invention
The shape of the lithium secondary battery is not particularly limited.
Type, coin type, cylindrical type, square type, etc.
Yes.
【００３１】[0031]
【実施例】以下、本発明を実施例によりさらに詳細に説
明するが、本発明はこれらによって何ら限定されるもの
ではない。なお、特に断らない限り、電極作製は下記の
条件で実施した。即ち、活物質としてニッケル酸リチウ
ム８８wt％、導電材としてアセチレンブラック（商品名
デンカブラック５０％プレス品、電気化学工業株式会社
製）６wt％、バインダーとしてフッ素樹脂（商品名テフ
ロン３０−Ｊ、三井・デュポンフロロケミカル株式会社
製）６wt％を水を用いて混練してペーストとし、集電体
となる＃２００ステンレスメッシュに塗布して１５０℃
で８時間真空乾燥を行った。また、使用したニッケル化
合物の平均粒径およびＢＥＴ比表面積は以下のようにし
て測定した。 平均粒径：分散媒として商品名Ｄａｒｖａｎ８２１Ａ
（Ｒ．Ｔ．Ｖａｎｄｅｒｂｉｌｔ社製）の０．２％水溶
液を用い、レーザー散乱式粒度分布測定装置（株式会社
島津製、ＳＡＬＤ１１００）により測定した粒度分布を
体積基準で微粒側から積算した場合の５０％粒子径（メ
ディアン径）を平均粒径とした。 ＢＥＴ比表面積：試料を５０℃で２時間真空乾燥した
後、マイクロメリティクス社製フローソーブII２３００
型を用いて測定した。EXAMPLES The present invention will now be described in more detail by way of examples, which should not be construed as limiting the invention thereto. In addition, unless otherwise specified, the electrodes were manufactured under the following conditions. That is, 88 wt% of lithium nickel oxide as an active material, 6 wt% of acetylene black (trade name Denka Black 50% pressed product, manufactured by Denki Kagaku Kogyo Co., Ltd.) as a conductive material, and fluororesin as a binder (trade name Teflon 30-J, Mitsui. DuPont Fluorochemicals Co., Ltd.) 6 wt% is kneaded with water to form a paste, which is applied to a # 200 stainless steel mesh serving as a current collector and applied at 150 ° C.
It was vacuum dried for 8 hours. The average particle size and BET specific surface area of the nickel compound used were measured as follows. Average particle size: Trade name Darvan821A as dispersion medium
50 when a particle size distribution measured by a laser scattering type particle size distribution measuring device (Shimadzu Corporation, SALD1100) is used from a fine particle side by volume, using a 0.2% aqueous solution (manufactured by RT Vanderbilt). The% particle size (median size) was defined as the average particle size. BET specific surface area: The sample was vacuum dried at 50 ° C. for 2 hours, and then flow-sorb II2300 manufactured by Micromeritics.
It was measured using a mold.
【００３２】実施例１ 硝酸リチウム（和光純薬工業株式会社、試薬特級グレー
ド）７．２３ｇをエタノール（和光純薬工業株式会社、
試薬特級グレード）１００ｇに溶解させ、さらに塩基性
炭酸ニッケル〔ＮｉＣＯ3 ・２Ｎｉ( ＯＨ)2・４Ｈ
2 Ｏ：和光純薬工業株式会社、試薬グレード、平均粒径
２０μｍ、ＢＥＴ比表面積２８６ｍ2 ／ｇ〕１２．５４
ｇを加えてよく分散させた後、ロータリーエバポレータ
ーを用いてエタノールを蒸発させた。得られた混合粉末
をめのう製乳鉢で軽く解砕した後、アルミナ炉心管を使
用した管状炉に入れ、酸素流量５０ｃｍ3 ／ｍｉｎの酸
素気流中において７００℃で１５時間焼成した。得られ
たニッケル酸リチウム粉末は、粉末Ｘ線回折によりα−
ＮａＦｅＯ2 型構造を有することが確認された。Example 1 7.23 g of lithium nitrate (Wako Pure Chemical Industries, Ltd., special grade reagent) was added to ethanol (Wako Pure Chemical Industries, Ltd.,
Dissolved in reagent special grade) 100 g, further basic nickel carbonate [NiCO 3 · 2Ni (OH) 2 · 4H
2 O: Wako Pure Chemical Industries, Ltd., reagent grade, average particle size 20 μm, BET specific surface area 286 m 2 / g] 12.54
After g was added and well dispersed, ethanol was evaporated using a rotary evaporator. The obtained mixed powder was lightly crushed in an agate mortar, put in a tubular furnace using an alumina core tube, and fired at 700 ° C. for 15 hours in an oxygen stream having an oxygen flow rate of 50 cm 3 / min. The obtained lithium nickelate powder was analyzed by powder X-ray diffraction to obtain α-
It was confirmed to have a NaFeO 2 type structure.
【００３３】該ニッケル酸リチウム粉末を電極に加工
し、電解質溶液としてプロピレンカーボネート（ＰＣ）
と１，２−ジメトキシエタン（ＤＭＥ）の１：１混合液
に過塩素酸リチウムを１モル／リットルとなるように溶
解したものを、セパレーターとしてポリプロピレン多孔
質膜を、また対極（負極）として金属リチウムをそれぞ
れ用いて平板型電池を作製した。The lithium nickel oxide powder was processed into an electrode, and propylene carbonate (PC) was used as an electrolyte solution.
A mixture of 1: 1 and 1,2-dimethoxyethane (DME) in which lithium perchlorate was dissolved at a concentration of 1 mol / liter was used as a separator, and a polypropylene porous film was used as a separator, and as a counter electrode (negative electrode), a metal A flat plate type battery was manufactured by using each of lithium.
【００３４】その後充電最大電圧Ｖmax ＝４．２Ｖ、放
電最小電圧Ｖmin ＝２．５Ｖ、０．１７ｍＡ／ｃｍ2 の
定電流で室温で充放電試験を実施した。第１回から第５
回までの充放電のクーロン効率および放電容量を表１に
示す。第１回の充放電におけるクーロン効率は８９％で
あった。Thereafter, a charge / discharge test was carried out at room temperature with a maximum charge voltage Vmax = 4.2V, a minimum discharge voltage Vmin = 2.5V and a constant current of 0.17 mA / cm 2 . 1st to 5th
Table 1 shows the Coulombic efficiency and the discharge capacity of charge and discharge up to the number of times. The Coulombic efficiency in the first charge / discharge was 89%.
【００３５】実施例２ 硝酸リチウム（和光純薬工業株式会社、試薬特級グレー
ド）１０．８５ｇをエタノール（和光純薬工業株式会
社、試薬特級グレード）１５０ｇに溶解させ、さらに三
酸化二ニッケル（ナカライテスク株式会社、ＥＰグレー
ド、平均粒径１４μm 、ＢＥＴ比表面積１３７ｍ2 ／
ｇ）１２．４１ｇを加えてよく分散させた後、実施例１
と同様に、ロータリーエバポレーターを用いてエタノー
ルを蒸発させ、酸素流量５０ｃｍ3 ／ｍｉｎの酸素気流
中において７００℃で１５時間焼成した。得られたニッ
ケル酸リチウム粉末は、粉末Ｘ線回折によりα−ＮａＦ
ｅＯ2型構造を有することが確認された。Example 2 10.85 g of lithium nitrate (Wako Pure Chemical Industries, Ltd. special grade reagent) was dissolved in 150 g of ethanol (Wako Pure Chemical Industries, Ltd. special grade reagent), and dinickel trioxide (Nacalai Tesque) was dissolved. Ltd., EP grade, average particle size 14 μm, BET specific surface area 137 m 2 /
g) 12.41 g was added and well dispersed, and then Example 1
Similarly to the above, ethanol was evaporated using a rotary evaporator, and the mixture was baked at 700 ° C. for 15 hours in an oxygen stream having an oxygen flow rate of 50 cm 3 / min. The obtained lithium nickelate powder was analyzed by powder X-ray diffraction to obtain α-NaF.
It was confirmed to have an eO 2 type structure.
【００３６】該ニッケル酸リチウム粉末を用いて実施例
１と同様の方法で平板型電池を作製し、Ｖmax ＝４．２
Ｖ、Ｖmin ＝２．５Ｖ、０．１７ｍＡ／ｃｍ2 の定電流
で室温で充放電試験を実施した。第１回から第５回まで
の充放電のクーロン効率および放電容量を表１に示す。
第１回の充放電におけるクーロン効率は８９％であっ
た。Using the lithium nickel oxide powder, a flat plate type battery was prepared in the same manner as in Example 1, and Vmax = 4.2.
A charge / discharge test was carried out at room temperature at a constant current of V, Vmin = 2.5V and 0.17 mA / cm 2 . Table 1 shows the Coulombic efficiency and discharge capacity of the first to fifth charging / discharging.
The Coulombic efficiency in the first charge / discharge was 89%.
【００３７】実施例３ 硝酸リチウム（和光純薬工業株式会社、試薬特級グレー
ド）７．２３ｇを純水１０ｇに溶解させ、さらに塩基性
炭酸ニッケル〔ＮｉＣＯ3 ・２Ｎｉ（ＯＨ）2・４Ｈ2
Ｏ：和光純薬工業株式会社、試薬グレード、平均粒径２
０μm 、ＢＥＴ比表面積２８６ｍ2 ／ｇ〕１２．５４ｇ
を加えてよく分散させた後、実施例１と同様に、ロータ
リーエバポレーターを用いて水を蒸発させ、酸素流量５
０ｃｍ3／ｍｉｎの酸素気流中において７００℃で１５
時間焼成した。得られたニッケル酸リチウム粉末は、粉
末Ｘ線回折によりα−ＮａＦｅＯ2 型構造を有すること
が確認された。Example 3 7.23 g of lithium nitrate (Wako Pure Chemical Industries, Ltd., special grade reagent) was dissolved in 10 g of pure water, and basic nickel carbonate [NiCO 3 .2Ni (OH) 2 .4H 2] was added.
O: Wako Pure Chemical Industries, Ltd., reagent grade, average particle size 2
0 μm, BET specific surface area 286 m 2 / g] 12.54 g
After adding well and dispersing well, water was evaporated using a rotary evaporator in the same manner as in Example 1, and the oxygen flow rate was 5
15 at 700 ° C in an oxygen stream of 0 cm 3 / min
Burned for hours. It was confirmed by powder X-ray diffraction that the obtained lithium nickelate powder had an α-NaFeO 2 type structure.
【００３８】該ニッケル酸リチウム粉末を用いて実施例
１と同様の方法で平板型電池を作製し、Ｖmax ＝４．２
Ｖ、Ｖmin ＝２．５Ｖ、０．１７ｍＡ／ｃｍ2 の定電流
で充放電試験を実施した。第１回から第５回までの充放
電のクーロン効率および放電容量を表１に示す。第１回
の充放電におけるクーロン効率は８６％であった。Using the lithium nickel oxide powder, a flat plate type battery was manufactured in the same manner as in Example 1, and Vmax = 4.2.
A charge / discharge test was conducted at V, Vmin = 2.5 V and a constant current of 0.17 mA / cm 2 . Table 1 shows the Coulombic efficiency and discharge capacity of the first to fifth charging / discharging. The Coulombic efficiency in the first charge / discharge was 86%.
【００３９】比較例１ 硝酸リチウム（和光純薬工業株式会社、試薬特級グレー
ド）１５．４６ｇと塩基性炭酸ニッケル〔ＮｉＣＯ3 ・
２Ｎｉ( ＯＨ)2・４Ｈ2 Ｏ：和光純薬工業株式会社、試
薬グレード、平均粒径２０μm 、ＢＥＴ比表面積２８６
ｍ2 ／ｇ〕２５．７１ｇをめのう製乳鉢で混合した後、
アルミナ炉心管を使用した管状炉に入れ、酸素流量５０
ｃｍ3 ／ｍｉｎの酸素気流中において７５０℃で１５時
間焼成した。得られたニッケル酸リチウム粉末は、粉末
Ｘ線回折によりα−ＮａＦｅＯ2型構造を有することが
確認された。Comparative Example 1 15.46 g of lithium nitrate (Wako Pure Chemical Industries, Ltd. special grade reagent) and basic nickel carbonate [NiCO 3 ·.
2Ni (OH) 2 · 4H 2 O: Wako Pure Chemical Industries, Ltd., reagent grade, average particle size 20 [mu] m, BET specific surface area 286
m 2 / g] After mixing 25.71 g in an agate mortar,
Put in a tubular furnace using alumina core tube, oxygen flow rate 50
It was fired at 750 ° C. for 15 hours in an oxygen stream of cm 3 / min. It was confirmed by powder X-ray diffraction that the obtained lithium nickelate powder had an α-NaFeO 2 type structure.
【００４０】該ニッケル酸リチウム粉末を用いて実施例
１と同様の方法で平板型電池を作製し、Ｖmax ＝４．２
Ｖ、Ｖmin ＝２．５Ｖ、０．１７ｍＡ／ｃｍ2 の定電流
で室温で充放電試験を実施した。第１回から第５回まで
の充放電のクーロン効率および放電容量を表１に示す。
第１回の充放電におけるクーロン効率は７９％であっ
た。Using the lithium nickel oxide powder, a flat plate type battery was manufactured in the same manner as in Example 1, and Vmax = 4.2.
A charge / discharge test was carried out at room temperature at a constant current of V, Vmin = 2.5V and 0.17 mA / cm 2 . Table 1 shows the Coulombic efficiency and discharge capacity of the first to fifth charging / discharging.
The Coulombic efficiency in the first charge / discharge was 79%.
【００４１】[0041]
【表１】 [Table 1]
【００４２】実施例４ 硝酸リチウム（和光純薬工業株式会社、試薬特級グレー
ド）１０８．６ｇを純水１５０ｇに溶解させ、さらに塩
基性炭酸ニッケル〔ＮｉＣＯ3 ・２Ｎｉ（ＯＨ）2 ・４
Ｈ2 Ｏ：和光純薬工業株式会社、試薬グレード、平均粒
径２０μｍ、ＢＥＴ比表面積２８６ｍ2 ／ｇ〕１８８．
１ｇを加えてよく分散させた後、実施例１と同様に、ロ
ータリーエバポレーターを用いて水を蒸発させ、酸素流
量５０ｃｍ3 ／ｍｉｎの酸素気流中において７００℃で
５時間焼成した。得られたニッケル酸リチウム粉末は、
粉末Ｘ線回折によりα−ＮａＦｅＯ2 型構造を有するこ
とが確認された。該ニッケル酸リチウム粉末と導電材と
しての人造黒鉛粉末（商品名ＫＳ−１５、Ｌｏｎｚａ社
製）を充分混合した後、バインダーとしてポリフッ化ビ
ニリデン（呉羽化学社製）、溶媒として１−メチル−２
−ピロリドン（和光純薬工業株式会社、試薬一級グレー
ド）を用いて作製したペーストをアルミ箔集電体の両面
に塗布、乾燥、ロールプレスを行って正極用電極シート
を得た。このときのニッケル酸リチウム粉末と、導電
材、バインダーの配合比率は重量比で８７：１０：３と
した。[0042] EXAMPLE 4 lithium nitrate (manufactured by Wako Pure Chemical Industries, Ltd., reagent special grade) was 108.6g dissolved in pure water 150 g, further basic nickel carbonate [NiCO 3 · 2Ni (OH) 2 · 4
H 2 O: Wako Pure Chemical Industries, Ltd., reagent grade, average particle size 20 μm, BET specific surface area 286 m 2 / g] 188.
After 1 g was added and well dispersed, water was evaporated using a rotary evaporator in the same manner as in Example 1, and the mixture was calcined at 700 ° C. for 5 hours in an oxygen stream having an oxygen flow rate of 50 cm 3 / min. The obtained lithium nickelate powder is
It was confirmed by powder X-ray diffraction that it had an α-NaFeO 2 type structure. After sufficiently mixing the lithium nickel oxide powder and artificial graphite powder (trade name KS-15, manufactured by Lonza) as a conductive material, polyvinylidene fluoride (manufactured by Kureha Chemical Co., Ltd.) as a binder and 1-methyl-2 as a solvent.
-Pyrrolidone (Wako Pure Chemical Industries, Ltd., first-grade reagent grade) was applied on both sides of an aluminum foil current collector, dried, and roll pressed to obtain a positive electrode sheet. The weight ratio of the lithium nickel oxide powder, the conductive material and the binder was 87: 10: 3.
【００４３】また、初回のクーロン効率測定用に、同様
にして片面塗布シートを作製した。この片面塗布シート
を用いて、実施例１と同様の方法で平板型電池を作製
し、Ｖｍａｘ＝４．２Ｖ、Ｖｍｉｎ＝２．５Ｖ、０．１
７ｍＡ／ｃｍ2 の定電流で室温で充放電試験を実施し
た。第１回の充放電におけるクーロン効率は８５％であ
った。次に平均粒径が６μｍのメソカーボンマイクロビ
ーズの黒鉛化炭素〔大阪ガス（株）製、ＭＣＭＢ６−２
８〕球状粉末とバインダーとしてポリフッ化ビニリデン
（呉羽化学社製）、溶媒として１−メチル−２−ピロリ
ドン（和光純薬工業株式会社、試薬一級グレード）を用
いて作製したペーストを銅箔集電体の両面に塗布、乾
燥、ロールプレスを行って負極用電極シートを得た。こ
のときの黒鉛化炭素球状粉末とバインダーの配合比率は
重量比で９０：１０とした。以上のようにして得た正極
と負極をポリプロピレン製セパレーターを介して巻き取
り、エチレンカーボネート（ＥＣ）とジメチルカーボネ
ート（ＤＭＣ）の１：１混合液に６フッ化燐酸リチウム
を１モル／リットルとなるように溶解した電解質溶液を
含浸して、円筒型電池（単三型）を作製した。この電池
を電流１００ｍＡ、定電圧４．２０Ｖで１５時間充電し
た後、定電流１００ｍＡで２．７５Ｖまで放電させた。
その後は電流１００ｍＡ、定電圧４．２０Ｖでの１２時
間充電と、定電流１００ｍＡで２．７５Ｖまでの放電を
繰り返した。初回、および３回目の放電容量はそれぞれ
６０３、および６０５ｍＡｈであった。A single-sided coated sheet was similarly prepared for the first Coulombic efficiency measurement. Using this single-sided coated sheet, a flat plate type battery was manufactured in the same manner as in Example 1, and Vmax = 4.2V, Vmin = 2.5V, 0.1.
A charge / discharge test was performed at room temperature with a constant current of 7 mA / cm 2 . The Coulombic efficiency in the first charge / discharge was 85%. Next, graphitized carbon of mesocarbon microbeads having an average particle size of 6 μm [MCMB6-2 manufactured by Osaka Gas Co., Ltd.
8] A copper foil current collector is a paste prepared by using spherical powder, polyvinylidene fluoride (manufactured by Kureha Chemical Co., Ltd.) as a binder, and 1-methyl-2-pyrrolidone (Wako Pure Chemical Industries, Ltd., first-grade reagent) as a solvent. Both sides were coated, dried and roll pressed to obtain an electrode sheet for negative electrode. The weight ratio of the graphitized carbon spherical powder to the binder was 90:10. The positive electrode and the negative electrode obtained as described above are wound with a polypropylene separator interposed therebetween, and 1 mol / liter of lithium hexafluorophosphate is added to a 1: 1 mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC). The thus-dissolved electrolyte solution was impregnated to prepare a cylindrical battery (AA battery). This battery was charged at a current of 100 mA and a constant voltage of 4.20 V for 15 hours and then discharged at a constant current of 100 mA to 2.75 V.
After that, charging was performed at a current of 100 mA and a constant voltage of 4.20 V for 12 hours, and discharging at a constant current of 100 mA to 2.75 V was repeated. The discharge capacities of the first and third times were 603 and 605 mAh, respectively.
【００４４】[0044]
【発明の効果】本発明のニッケル酸リチウムを含む正極
材料は、高価なコバルト化合物を原料とするコバルト酸
リチウムよりも、資源的に豊富で安価であるニッケル化
合物を用いているので材料コストの面から有利である。
さらに、初回の充放電において８０％以上のクーロン効
率を示す本発明のリチウム二次電池用正極材料を、リチ
ウム金属、リチウム合金、またはリチウムイオンをドー
プ・脱ドープ可能な材料を含む負極と、液体または固体
の電解質とを有するリチウム二次電池に用いると優れた
充放電特性を有するリチウム二次電池を得ることがで
き、工業的価値は極めて大きい。The positive electrode material containing lithium nickelate according to the present invention uses a nickel compound which is resource-rich and cheaper than lithium cobaltate prepared from an expensive cobalt compound as a raw material. Is advantageous.
Furthermore, a positive electrode material for a lithium secondary battery of the present invention that exhibits a Coulombic efficiency of 80% or more in the first charge and discharge, a negative electrode containing a lithium metal, a lithium alloy, or a material capable of being doped / dedoped with lithium ions Alternatively, when used in a lithium secondary battery having a solid electrolyte, a lithium secondary battery having excellent charge / discharge characteristics can be obtained, and its industrial value is extremely large.
Claims (12)
％以上であることを特徴とするα−ＮａＦｅＯ2 型構造
を有するニッケル酸リチウムを含むリチウム二次電池正
極材料。1. The Coulomb efficiency in the first charge and discharge is 80.
% Or more, a lithium secondary battery positive electrode material containing lithium nickelate having an α-NaFeO 2 type structure.
散させた後溶媒を揮散させ、硝酸リチウムとニッケル化
合物との混合物（ただし、硝酸リチウムとニッケル化合
物との混合比が等モルの場合を除く。）を得て、酸素を
含む雰囲気下で該混合物を焼成することを特徴とする請
求項１記載のニッケル酸リチウムの製造方法。2. A mixture of a lithium compound and a nickel compound after dispersing a nickel compound in a lithium nitrate solution and excluding the solvent (except when the mixing ratio of lithium nitrate and nickel compound is equimolar). (2) is obtained and the mixture is fired in an atmosphere containing oxygen.
散させた後溶媒を揮散させ、硝酸リチウムとニッケル化
合物〔ただし、ＮｉＣＯ3 ・ｗＨ2 Ｏ（式中、ｗ≧０）
を除く。〕との混合物を得て、酸素を含む雰囲気下で該
混合物を焼成することを特徴とする請求項１記載のニッ
ケル酸リチウムの製造方法。3. A lithium compound is dispersed in a lithium nitrate solution and then the solvent is volatilized to obtain lithium nitrate and a nickel compound [where NiCO 3 .wH 2 O (where, w ≧ 0)].
except for. ] The method for producing lithium nickelate according to claim 1, wherein the mixture is obtained and the mixture is fired in an atmosphere containing oxygen.
びアルコール類の中から選ばれた少なくとも一種である
ことを特徴とする請求項２または３記載のニッケル酸リ
チウムの製造方法。4. The method for producing lithium nickelate according to claim 2, wherein the solvent for dissolving lithium nitrate is at least one selected from water and alcohols.
ることを特徴とする請求項２または３記載のニッケル酸
リチウムの製造方法。5. The method for producing lithium nickel oxide according to claim 2, wherein the nickel compound is basic nickel carbonate.
散させる場合、ニッケル化合物を真空容器に入れ真空に
した後、硝酸リチウム溶液を添加し真空含浸することを
特徴とする請求項２または３記載のニッケル酸リチウム
の製造方法。6. The method according to claim 2, wherein when the nickel compound is dispersed in the lithium nitrate solution, the nickel compound is placed in a vacuum container and evacuated, and then the lithium nitrate solution is added and vacuum impregnated. Method for producing lithium nickelate.
が１．０＜Ｌｉ／Ｎｉ≦１．１の範囲であることを特徴
とする請求項２記載のニッケル酸リチウムの製造方法。7. The method for producing lithium nickelate according to claim 2, wherein the mixing ratio of lithium nitrate and nickel compound is in the range of 1.0 <Li / Ni ≦ 1.1.
が１．０≦Ｌｉ／Ｎｉ≦１．１の範囲であることを特徴
とする請求項３記載のニッケル酸リチウムの製造方法。8. The method for producing lithium nickelate according to claim 3, wherein the mixing ratio of lithium nitrate and the nickel compound is in the range of 1.0 ≦ Li / Ni ≦ 1.1.
請求項２または３記載のニッケル酸リチウムの製造方
法。9. The method for producing lithium nickelate according to claim 2, wherein the firing atmosphere is oxygen.
の混合粉末を硝酸リチウムの融点未満の温度で乾燥する
ことを特徴とする請求項２または３記載のニッケル酸リ
チウムの製造方法。10. The method for producing lithium nickelate according to claim 2, wherein the mixed powder of lithium nitrate and a nickel compound is dried at a temperature lower than the melting point of lithium nitrate before firing.
あることを特徴とする請求項２または３記載のニッケル
酸リチウムの製造方法。11. The method for producing lithium nickelate according to claim 2, wherein the firing temperature is 350 ° C. or higher and 800 ° C. or lower.
チウムイオンをドープ・脱ドープ可能な材料を含む負極
と、リチウムイオンをドープ・脱ドープ可能な材料を含
む正極と、液体または固体の電解質とを有するリチウム
二次電池において、該正極として請求項１記載のリチウ
ム二次電池正極材料を用いることを特徴とするリチウム
二次電池。12. A negative electrode containing lithium metal, a lithium alloy, or a material capable of doping / dedoping lithium ions, a positive electrode containing a material capable of doping / dedoping lithium ions, and a liquid or solid electrolyte. A lithium secondary battery, wherein the positive electrode material for a lithium secondary battery according to claim 1 is used as the positive electrode in a lithium secondary battery.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15740094A JP3577744B2 (en) | 1993-07-15 | 1994-07-08 | Lithium secondary battery positive electrode material and method for producing lithium nickelate |
Applications Claiming Priority (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17519893 | 1993-07-15 | ||
| JP5-175198 | 1993-07-15 | ||
| JP5-330242 | 1993-12-27 | ||
| JP33024293 | 1993-12-27 | ||
| JP9837994 | 1994-05-12 | ||
| JP6-98379 | 1994-05-12 | ||
| JP15740094A JP3577744B2 (en) | 1993-07-15 | 1994-07-08 | Lithium secondary battery positive electrode material and method for producing lithium nickelate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0831418A true JPH0831418A (en) | 1996-02-02 |
| JP3577744B2 JP3577744B2 (en) | 2004-10-13 |
Family
ID=27468628
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15740094A Expired - Fee Related JP3577744B2 (en) | 1993-07-15 | 1994-07-08 | Lithium secondary battery positive electrode material and method for producing lithium nickelate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3577744B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6015637A (en) * | 1996-09-30 | 2000-01-18 | Sharp Kabushiki Kaisha | Process of producing lithium nickel oxide and nonaqueous secondary battery using the same |
| US6344294B1 (en) | 1998-10-27 | 2002-02-05 | Sharp Kabushiki Kaisha | Process for preparing a positive electrode active material for a nonaqueous secondary battery by forming an oxalate precipitate |
| CN113972364A (en) * | 2021-09-30 | 2022-01-25 | 广东邦普循环科技有限公司 | Preparation method of layered carbon-doped sodium iron phosphate cathode material |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115101745A (en) * | 2022-07-12 | 2022-09-23 | 上海交通大学 | Micro lithium-rich lithium nickelate positive electrode material with layered structure, preparation method and application of material in lithium ion battery |
-
1994
- 1994-07-08 JP JP15740094A patent/JP3577744B2/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6015637A (en) * | 1996-09-30 | 2000-01-18 | Sharp Kabushiki Kaisha | Process of producing lithium nickel oxide and nonaqueous secondary battery using the same |
| US6344294B1 (en) | 1998-10-27 | 2002-02-05 | Sharp Kabushiki Kaisha | Process for preparing a positive electrode active material for a nonaqueous secondary battery by forming an oxalate precipitate |
| CN113972364A (en) * | 2021-09-30 | 2022-01-25 | 广东邦普循环科技有限公司 | Preparation method of layered carbon-doped sodium iron phosphate cathode material |
| CN113972364B (en) * | 2021-09-30 | 2023-03-24 | 广东邦普循环科技有限公司 | Preparation method of layered carbon-doped sodium iron phosphate cathode material |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3577744B2 (en) | 2004-10-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5808073B2 (en) | Positive electrode active material and positive electrode and lithium battery employing the same | |
| US9005810B2 (en) | Cathode active material, cathode and non-aqueous secondary battery | |
| JP3222022B2 (en) | Method for producing lithium secondary battery and negative electrode active material | |
| JP4985524B2 (en) | Lithium secondary battery | |
| US20020182497A1 (en) | Carbon-containing lithium-iron composite phosphorus oxide for lithium secondary battery positive electrode active material and process for producing the same | |
| KR20010040161A (en) | Active material for non-aqueous secondary battery and non-aqueous secondary battery using the same | |
| WO2009053823A2 (en) | Positive electrode active material, lithium secondary battery, and manufacture methods therefore | |
| WO2009096255A1 (en) | Positive electrode active material, positive electrode, and nonaqueous rechargeable battery | |
| EP0643430B1 (en) | Cathode material for lithium secondary battery and method for producing lithiated nickel dioxide and lithium secondary battery | |
| JP5312099B2 (en) | Method for producing positive electrode active material and positive electrode active material | |
| EP3534443A1 (en) | Positive electrode active material for potassium ion battery, positive electrode for potassium ion battery, and potassium ion battery | |
| JP2007053081A (en) | Positive active material for nonaqueous electrolyte secondary battery | |
| KR20120117234A (en) | Cathode active material, preparation method thereof, and cathode and lithium battery containing the material | |
| KR101551407B1 (en) | Negative electrode active material for rechargeable lithium battery, method for preparing the same, negative electrode including the same, and rechargeable lithium battery including the negative electrode | |
| US20200403224A1 (en) | Lithium molybdate anode material | |
| JP2003017056A (en) | Lithium transition-metal compound oxide for positive electrode active material for lithium secondary battery, and lithium secondary battery using the same | |
| JP2004299944A (en) | Graphite particle, its producing method, lithium ion secondary battery and negative electrode material for it | |
| JP2013062190A (en) | Positive electrode material and storage battery manufactured using the same | |
| WO2007011053A1 (en) | Positive electrode active material for nonaqueous electrolyte secondary battery | |
| US20200106096A1 (en) | Positive active material for potassium secondary battery and potassium secondary battery including the same | |
| JP5565391B2 (en) | Electrode active material, method for producing the electrode active material, and lithium secondary battery including the electrode active material | |
| JP3577744B2 (en) | Lithium secondary battery positive electrode material and method for producing lithium nickelate | |
| JP2002117845A (en) | Lithium iron complex oxide for lithium secondary battery positive electrode active material | |
| JP6503768B2 (en) | Lithium ion secondary battery | |
| JP6360374B2 (en) | Method for producing lithium-containing composite metal oxide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20031212 |
|
| A911 | Transfer of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20040223 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20040316 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20040514 |
|
| 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: 20040622 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20040705 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| 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 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080723 Year of fee payment: 4 |
|
| RD05 | Notification of revocation of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: R3D05 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080723 Year of fee payment: 4 |
|
| RD05 | Notification of revocation of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: R3D05 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090723 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100723 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110723 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110723 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120723 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120723 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130723 Year of fee payment: 9 |
|
| LAPS | Cancellation because of no payment of annual fees |