JPH10251020A - Metal substituted lithium titanate, its production and lithium battery using the same - Google Patents
Metal substituted lithium titanate, its production and lithium battery using the sameInfo
- Publication number
- JPH10251020A JPH10251020A JP9076635A JP7663597A JPH10251020A JP H10251020 A JPH10251020 A JP H10251020A JP 9076635 A JP9076635 A JP 9076635A JP 7663597 A JP7663597 A JP 7663597A JP H10251020 A JPH10251020 A JP H10251020A
- Authority
- JP
- Japan
- Prior art keywords
- lithium
- metal
- lithium titanate
- titanate
- compound
- 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.)
- Pending
Links
Classifications
-
- 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
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
-
- 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]
【発明の属する技術分野】本発明は、リチウム電池の電
極材料などとして有用な金属置換チタン酸リチウムおよ
びその製造方法ならびにそれを用いてなるリチウム電池
に関する。The present invention relates to a metal-substituted lithium titanate useful as an electrode material for a lithium battery, a method for producing the same, and a lithium battery using the same.
【０００２】[0002]
【従来の技術】チタン酸リチウムの代表的化合物として
はＬｉ2.67Ｔｉ1.33Ｏ4 、ＬｉＴｉ2Ｏ4 、Ｌｉ1.33Ｔ
ｉ1.67Ｏ4 、Ｌｉ1.14Ｔｉ1.71Ｏ4 などがある。このチ
タン酸リチウムを得るには、酸化チタンとリチウム化合
物との混合物を７００〜１６００℃の温度で乾式加熱処
理する方法が用いられている（特開平６−２７５２６３
号を参照）。 2. Description of the Related Art Representative compounds of lithium titanate include Li 2.67 Ti 1.33 O 4 , LiTi 2 O 4 , and Li 1.33 T
i 1.67 O 4 and Li 1.14 Ti 1.71 O 4 . In order to obtain this lithium titanate, a method in which a mixture of titanium oxide and a lithium compound is dry-heat-treated at a temperature of 700 to 1600 ° C. is used (Japanese Patent Laid-Open No. 6-275263).
No.).
【０００３】[0003]
【発明が解決しようとする課題】前記の従来技術の方法
で得られるチタン酸リチウムは、粒子間の焼結が不均一
に起こった焼結体であるため、粒子の大きさや形状を制
御できないという問題がある。さらには、チタン酸リチ
ウムを得る反応が酸化チタン粉末とリチウム化合物粉末
との固固反応であるため、熱処理を高温度で行っても反
応性が悪く、未反応の原料粉末が多く残存するという問
題もある。一方、酸化チタンとリチウム化合物との混合
物を７００℃以下の低い温度で熱処理すると、反応が進
まずチタン酸リチウムが得られ難いという問題がある。The lithium titanate obtained by the above-mentioned prior art method is a sintered body in which sintering between particles has occurred unevenly, so that the size and shape of the particles cannot be controlled. There's a problem. Furthermore, since the reaction for obtaining lithium titanate is a solid-solid reaction between the titanium oxide powder and the lithium compound powder, even if the heat treatment is performed at a high temperature, the reactivity is poor, and a large amount of unreacted raw material powder remains. There is also. On the other hand, when a mixture of titanium oxide and a lithium compound is heat-treated at a low temperature of 700 ° C. or less, there is a problem that the reaction does not proceed and it is difficult to obtain lithium titanate.
【０００４】[0004]
【課題を解決するための手段】本発明者等は、リチウム
電池の電極材料などとして有用なチタン酸リチウム化合
物を得るべく種々検討した。その結果、従来法である乾
式加熱法で得られたチタン酸リチウムを水、アルコール
等の溶媒中で２以上の原子価を有する金属化合物と接触
させることにより、チタン酸リチウムのリチウム成分の
一部が２以上の原子価を有する金属でイオン交換され
て、２以上の原子価を有する金属で置換されたチタン酸
リチウムが得られること、しかも、チタン酸リチウムと
して、チタン酸化合物とリチウム化合物とを湿式反応さ
せて得られたチタン酸リチウム水和物を熱処理して得ら
れたものを用い、このものを２以上の原子価を有する金
属化合物と溶媒中で接触させてイオン交換すると、粒子
の大きさや形状が制御された金属置換チタン酸リチウム
が得られることなどを見出して本発明を完成した。Means for Solving the Problems The present inventors have made various studies to obtain a lithium titanate compound useful as an electrode material for a lithium battery. As a result, by bringing lithium titanate obtained by a conventional dry heating method into contact with a metal compound having a valence of 2 or more in a solvent such as water or alcohol, a part of the lithium component of lithium titanate is obtained. Is ion-exchanged with a metal having a valence of 2 or more to obtain a lithium titanate substituted with a metal having a valence of 2 or more. In addition, as the lithium titanate, a titanate compound and a lithium compound are used. Using a lithium titanate hydrate obtained by performing a wet reaction and heat-treating the same, this is brought into contact with a metal compound having a valence of 2 or more in a solvent to perform ion exchange to obtain a particle size of The inventors have found that a metal-substituted lithium titanate having a controlled sheath shape can be obtained, and completed the present invention.
【０００５】すなわち、本発明は、チタン酸リチウムの
リチウム成分の一部が２以上の原子価を有する金属で置
換されている金属置換チタン酸リチウム、さらには、そ
の粒子の大きさや形状が制御された金属置換チタン酸リ
チウムを提供することにある。また、本発明は、前記の
金属置換チタン酸リチウムを効率よく製造する方法を提
供することにある。さらに、本発明は、前記の金属置換
チタン酸リチウムを用いたリチウム電池用電極、さらに
は、それを用いたリチウム電池を提供することにある。That is, according to the present invention, there is provided a metal-substituted lithium titanate in which part of the lithium component of lithium titanate is substituted by a metal having a valence of 2 or more, and further, the size and shape of the particles are controlled. To provide a metal-substituted lithium titanate. Another object of the present invention is to provide a method for efficiently producing the metal-substituted lithium titanate. Further, the present invention is to provide a lithium battery electrode using the above-mentioned metal-substituted lithium titanate, and a lithium battery using the same.
【０００６】本発明は、一般式ＬｉX ＭY ＴｉZ Ｏ
4 （但し、Ｍは２以上の原子価を有する金属）で表され
る金属置換チタン酸リチウムに関し、このものは金属置
換チタン酸リチウムの単一相からなるもの、金属置換チ
タン酸リチウムと酸化チタンとの混合物からなるものの
いずれをも包含する。前記一般式中のＸ、Ｙ及びＺの値
は、（Ｘ＋Ｙ）／Ｚの値が０．５〜２の範囲になるもの
が好ましい。本発明においてリチウム成分の一部と置換
する金属としては、２以上の原子価を有するものであれ
ば、特に制限なく用いることができるが、コバルト、ニ
ッケル、マンガン、バナジウム、鉄、ホウ素、アルミニ
ウム、珪素、ジルコニウム、ストロンチウム、マグネシ
ウム及び錫からなる群より選ばれる少なくとも１種の金
属が好ましい。２以上の原子価を有する金属でリチウム
成分の一部を置換することにより、リチウムイオンのド
ープ、脱ドープが容易となり、リチウム電池用電極とし
て用いた場合に電池容量等の特性を改善することができ
る。本発明の金属置換チタン酸リチウム粒子の大きさ
は、比表面積として１〜３００ｍ2 ／ｇ、好ましくは５
〜３００ｍ2 ／ｇ、より好ましくは１０〜３００ｍ2 ／
ｇであり、この範囲を逸脱するとリチウム電池の電極材
料などに用いる際に必要な特性が得られ難くなる。The present invention relates to a compound represented by the general formula Li X MY Ti Z O
4 (where M is a metal having a valence of 2 or more), which is a metal-substituted lithium titanate consisting of a single phase of metal-substituted lithium titanate, a metal-substituted lithium titanate and titanium oxide And mixtures thereof. It is preferable that the value of X, Y and Z in the general formula is such that the value of (X + Y) / Z is in the range of 0.5 to 2. In the present invention, as the metal to be substituted for a part of the lithium component, any metal having a valence of 2 or more can be used without any particular limitation. However, cobalt, nickel, manganese, vanadium, iron, boron, aluminum, At least one metal selected from the group consisting of silicon, zirconium, strontium, magnesium and tin is preferred. By replacing a part of the lithium component with a metal having a valence of 2 or more, doping and undoping of lithium ions is facilitated, and when used as a lithium battery electrode, characteristics such as battery capacity can be improved. it can. The metal-substituted lithium titanate particles of the present invention have a specific surface area of 1 to 300 m 2 / g, preferably 5 to 300 m 2 / g.
~300m 2 / g, more preferably 10~300m 2 /
g, and if it deviates from this range, it becomes difficult to obtain the characteristics required for use as an electrode material of a lithium battery.
【０００７】本発明の金属置換チタン酸リチウム粒子は
板状形状をしており、このような板状形状は電子顕微鏡
観察により確認することができる。その粒子径（最長
径）は適宜設計することができるが、普通、０．１〜５
０μｍ、好ましくは０．２〜３０μｍである。この範囲
を逸脱するとリチウム電池の電極材料などに用いる際に
必要な特性が得られ難くなる。The metal-substituted lithium titanate particles of the present invention have a plate-like shape, and such a plate-like shape can be confirmed by observation with an electron microscope. The particle diameter (longest diameter) can be appropriately designed, but is usually 0.1 to 5
0 μm, preferably 0.2 to 30 μm. If the ratio deviates from this range, it becomes difficult to obtain characteristics required for use as an electrode material of a lithium battery.
【０００８】次に、本発明は一般式ＬｉX ＴｉY Ｏ
4 （但し、０．５≦Ｘ／Ｙ≦２）で表されるチタン酸リ
チウムのリチウム成分の一部を２以上の原子価を有する
金属でイオン交換することを特徴とする、一般式ＬｉX
ＭY ＴｉZ Ｏ4 （但し、Ｍは２以上の原子価を有する金
属であって、０．５≦（Ｘ＋Ｙ）／Ｚ≦２）で表される
金属置換チタン酸リチウムの製造方法である。イオン交
換は、例えば、水、アルコール、セルソルブ、メチルエ
チルケトン、キシレン、トルエン等の溶媒に一般式Ｌｉ
X ＴｉY Ｏ4 （但し、０．５≦Ｘ／Ｙ≦２）で表される
チタン酸リチウムを懸濁させ、この中に、必要に応じて
酸又はアルカリを添加してｐＨを４〜１２に調整して、
２以上の原子価を有する金属の化合物を添加することに
より行うことができる。この場合、イオン交換して得ら
れた金属置換チタン酸リチウムを２５０℃以下の温度で
さらに水熱処理することにより、特性を一層向上させる
ことができる。２以上の原子価を有する金属の化合物と
しては、特に制限はないが、それらの中でも前記のコバ
ルト、ニッケル、マンガン、バナジウム、鉄、ホウ素、
アルミニウム、珪素、ジルコニウム、ストロンチウム、
マグネシウム及び錫からなる群より選ばれる少なくとも
１種の金属の化合物が好ましく、より好ましくは前記金
属のアンモニア錯塩、塩化物、水酸化物、硝酸塩、炭酸
塩、硫酸塩、酢酸塩、およびそれらのオキシ塩、さらに
はそれらの金属アルコキシドなどの有機金属化合物であ
る。このような金属とイオン交換することにより本発明
の金属置換チタン酸リチウムが得られる。Next, the present invention relates to the general formula Li x Ti YO
4 (where, 0.5 ≦ X / Y ≦ 2 ) , characterized in that ion exchange with a metal having 2 or more valence of the part of the lithium component in the lithium titanate represented by the general formula Li X
M Y Ti Z O 4 (where, M is a metal with two or more valences, 0.5 ≦ (X + Y) / Z ≦ 2) is a method of manufacturing the metal-substituted lithium titanate represented. The ion exchange is performed, for example, by adding a solvent such as water, alcohol, cellosolve, methyl ethyl ketone, xylene, or toluene to a compound of the general formula Li.
X Ti Y O 4 (However, lithium titanate represented by 0.5 ≦ X / Y ≦ 2) is suspended, and an acid or an alkali is added thereto as necessary to adjust the pH to 4 to 12. Adjust to
It can be carried out by adding a compound of a metal having a valence of 2 or more. In this case, the properties can be further improved by further hydrothermally treating the metal-substituted lithium titanate obtained by ion exchange at a temperature of 250 ° C. or lower. The compound of the metal having a valence of 2 or more is not particularly limited, but among them, the above-mentioned cobalt, nickel, manganese, vanadium, iron, boron,
Aluminum, silicon, zirconium, strontium,
Compounds of at least one metal selected from the group consisting of magnesium and tin are preferred, and more preferred are ammonia complex salts, chlorides, hydroxides, nitrates, carbonates, sulfates, acetates, and oxyforms thereof. Salts, and organometallic compounds such as metal alkoxides thereof. By performing ion exchange with such a metal, the metal-substituted lithium titanate of the present invention can be obtained.
【０００９】一般式ＬｉX ＴｉY Ｏ4 （但し、０．５≦
Ｘ／Ｙ≦２）で表されるチタン酸リチウムを得るには、
酸化チタンとリチウム化合物との混合物を７００〜１
６００℃の温度で熱処理する方法、チタン化合物とア
ンモニウム化合物とを水系媒液中で反応させてチタン酸
化合物を得る第１工程、該チタン酸化合物とリチウム化
合物とを水系媒液中で反応させてチタン酸リチウム水和
物を得る第２工程、該チタン酸リチウム水和物を熱処理
する第３工程からなる方法等がある。本発明において
は、の方法で得られる一般式ＬｉX ＴｉY Ｏ4 （但
し、０．５≦Ｘ／Ｙ≦２）で表されるチタン酸リチウム
を用いると、粒子の大きさや形状が制御された金属置換
チタン酸リチウムが得られるので好ましい。The general formula Li X Ti Y O 4 (provided that 0.5 ≦
In order to obtain lithium titanate represented by X / Y ≦ 2),
700 to 1 mixture of titanium oxide and lithium compound
A heat treatment at a temperature of 600 ° C., a first step of reacting a titanium compound and an ammonium compound in an aqueous medium to obtain a titanate compound, and reacting the titanate compound and the lithium compound in an aqueous medium. There is a method including a second step of obtaining lithium titanate hydrate and a third step of heat-treating the lithium titanate hydrate. In the present invention, when the lithium titanate represented by the general formula Li x Ti Y O 4 (provided that 0.5 ≦ X / Y ≦ 2) obtained by the method is used, the size and shape of the particles are controlled. It is preferable because a metal-substituted lithium titanate can be obtained.
【００１０】前記の方法において、第１工程はチタン
化合物とアンモニウム化合物とを水系媒液中で反応させ
てチタン酸化合物を得る工程である。チタン酸化合物と
は、オルトチタン酸、オルトチタン酸の水素イオンの一
部がアンモニウムイオン等で置換されたもの等を意味す
る。チタン化合物としては、硫酸チタン、硫酸チタニ
ル、塩化チタンなどの無機チタン化合物やチタンアルコ
キシドなどの有機チタン化合物を使用することができ
る。特に、金属置換チタン酸リチウム内の不純物残量を
少なくできる塩化チタンを使用するのが好ましい。ま
た、アンモニウム化合物としては、アンモニア水、炭酸
アンモニウム、硫酸アンモニウム、硝酸アンモニウムな
どを使用することができる。このアンモニウム化合物に
代えて、ナトリウム化合物、カリウム化合物などのアル
カリ金属化合物を使用すると、得られるチタン酸化合物
内にナトリウムやカリウムなどの成分が残留し、その後
の加熱脱水の際に粒子間の焼結を引き起こし、粒子の大
きさや形状を不均一にし易いので好ましくない。水系媒
液としては、水、水−アルコールなどを使用することが
できる。チタン化合物とアンモニウム化合物とを水系媒
液中で混合することにより反応が進み、オルトチタン酸
（Ｈ4 ＴｉＯ4 ）またはその水素イオンがアンモニウム
イオンに置換されたＨ4-n （ＮＨ4 ）n ＴｉＯ4 で表さ
れる化合物であるチタン酸化合物が得られる。Ｈ
4-n （ＮＨ4 ）n ＴｉＯ4 のアンモニウムイオンの置換
量は、反応の際のアンモニウムイオン濃度、遊離水酸基
濃度、水素イオン濃度や反応温度などの条件を調整する
ことにより任意に変えられる。得られるチタン酸化合物
の粒子径は、その後の工程で得られるチタン酸リチウム
の粒子径に影響を及ぼすため、この第１工程は重要であ
り、微粒子状のチタン酸化合物、さらには、微粒子状の
チタン酸リチウムとするために、反応温度を０〜５０
℃、好ましくは５〜４０℃、より好ましくは１０〜３０
℃に設定する。In the above method, the first step is a step of reacting a titanium compound and an ammonium compound in an aqueous medium to obtain a titanate compound. The titanate compound means orthotitanic acid, a compound in which a part of hydrogen ions of orthotitanic acid is substituted with ammonium ion or the like. As the titanium compound, an inorganic titanium compound such as titanium sulfate, titanyl sulfate, and titanium chloride, and an organic titanium compound such as titanium alkoxide can be used. In particular, it is preferable to use titanium chloride which can reduce the remaining amount of impurities in the metal-substituted lithium titanate. Further, as the ammonium compound, aqueous ammonia, ammonium carbonate, ammonium sulfate, ammonium nitrate and the like can be used. When an alkali metal compound such as a sodium compound or a potassium compound is used in place of the ammonium compound, components such as sodium and potassium remain in the obtained titanate compound, and sintering between particles occurs during subsequent heating and dehydration. Is caused, and the size and shape of the particles tend to be non-uniform. As the aqueous medium, water, water-alcohol, or the like can be used. The reaction proceeds by mixing the titanium compound and the ammonium compound in an aqueous medium, and H 4 -n (NH 4 ) n TiO in which orthotitanic acid (H 4 TiO 4 ) or its hydrogen ion has been replaced by ammonium ion. Thus , a titanate compound represented by 4 is obtained. H
The replacement amount of ammonium ion of 4-n (NH 4 ) n TiO 4 can be arbitrarily changed by adjusting conditions such as ammonium ion concentration, free hydroxyl group concentration, hydrogen ion concentration and reaction temperature during the reaction. Since the particle size of the obtained titanate compound affects the particle size of the lithium titanate obtained in the subsequent step, the first step is important, and the fine titanate compound, and further, the fine particle titanate compound, In order to obtain lithium titanate, the reaction temperature is 0 to 50.
° C, preferably 5 to 40 ° C, more preferably 10 to 30 ° C.
Set to ° C.
【００１１】このようにして得られたチタン酸化合物
を、必要に応じて、濾過したり、洗浄したり、酸洗浄し
たり、あるいは乾燥したりして、次の第２工程の処理に
供する。The titanate compound thus obtained is filtered, washed, acid-washed or dried, if necessary, and then subjected to the second step.
【００１２】第２工程は、前記第１工程で得られたチタ
ン酸化合物とリチウム化合物とを水系媒液中で反応させ
てチタン酸リチウム水和物を得る工程である。リチウム
化合物としては、水酸化リチウム、炭酸リチウム、硝酸
リチウム、硫酸リチウムなどの水可溶性リチウム化合物
を用いることができる。このリチウム化合物とチタン酸
化合物とを水系媒液中で混合することにより反応が進
む。反応温度は、５０℃以上、好ましくは１００℃以
上、より好ましくは１００〜２５０℃であり、最も好ま
しくは１３０〜２００℃である。この温度範囲で反応さ
せることにより結晶性の優れたチタン酸リチウム水和物
を得ることができる。１００℃以上の温度で反応を行う
場合には、リチウム化合物とチタン酸化合物とをオート
クレーブに入れ、飽和蒸気圧下または加圧下で水熱処理
するのが好ましい。この水熱処理により、板状形状を有
するチタン酸リチウム水和物を得ることができる。水熱
処理をアンモニアの存在下で行うと、より低い温度で結
晶性の良い、形状の整ったチタン酸リチウム水和物が得
られる。The second step is a step of reacting the titanate compound obtained in the first step with a lithium compound in an aqueous medium to obtain lithium titanate hydrate. As the lithium compound, a water-soluble lithium compound such as lithium hydroxide, lithium carbonate, lithium nitrate, and lithium sulfate can be used. The reaction proceeds by mixing the lithium compound and the titanate compound in an aqueous medium. The reaction temperature is 50 ° C. or higher, preferably 100 ° C. or higher, more preferably 100 to 250 ° C., and most preferably 130 to 200 ° C. By reacting in this temperature range, a lithium titanate hydrate having excellent crystallinity can be obtained. When the reaction is carried out at a temperature of 100 ° C. or higher, it is preferable that the lithium compound and the titanate compound are placed in an autoclave and subjected to hydrothermal treatment under a saturated vapor pressure or under a pressure. By this hydrothermal treatment, a lithium titanate hydrate having a plate shape can be obtained. When the hydrothermal treatment is performed in the presence of ammonia, a well-crystallized and well-shaped lithium titanate hydrate can be obtained at a lower temperature.
【００１３】このようにして得られたチタン酸リチウム
水和物を濾過し、必要に応じて洗浄したり、乾燥したり
する。乾燥温度は、チタン酸リチウム水和物が結晶水を
放出する温度以下の温度であれば適宜設定することがで
き、３０〜２００℃の温度が適当である。The thus obtained lithium titanate hydrate is filtered, and, if necessary, washed and dried. The drying temperature can be appropriately set as long as the temperature is lower than the temperature at which lithium titanate hydrate releases water of crystallization, and a temperature of 30 to 200 ° C is appropriate.
【００１４】第３工程は、前記第２の工程で得られたチ
タン酸リチウム水和物を熱処理して一般式ＬｉX ＴｉY
Ｏ4 （但し、０．５≦Ｘ／Ｙ≦２）で表されるチタン酸
リチウムを得る工程である。熱処理の温度は、チタン酸
リチウム水和物が結晶水を放出する温度以上の温度か
ら、得られるチタン酸リチウムの比表面積が１ｍ2 ／ｇ
となる温度以下の温度までである。この熱処理の温度範
囲は、チタン酸リチウム水和物の組成や結晶水の量など
で異なる場合があると考えられるが、２００〜８００℃
程度であり、比表面積の大きなチタン酸リチウムを得る
うえでは、２５０〜７００℃の範囲が好ましく、３５０
〜６５０℃の範囲がより好ましい。In the third step, the lithium titanate hydrate obtained in the second step is subjected to a heat treatment to obtain a compound of the general formula Li x Ti Y
This is a step of obtaining lithium titanate represented by O 4 (provided that 0.5 ≦ X / Y ≦ 2). The temperature of the heat treatment is from the temperature at which the lithium titanate hydrate releases water of crystallization, and the specific surface area of the obtained lithium titanate is 1 m 2 / g.
Up to the temperature below. The temperature range of this heat treatment may vary depending on the composition of lithium titanate hydrate, the amount of water of crystallization, and the like.
In order to obtain lithium titanate having a large specific surface area, the temperature is preferably in the range of 250 to 700 ° C.
The range of -650 degreeC is more preferable.
【００１５】さらに、本発明は、前記の一般式ＬｉX Ｍ
Y ＴｉZ Ｏ4 （但し、Ｍは２以上の原子価を有する金属
であって、０．５≦（Ｘ＋Ｙ）／Ｚ≦２）で表される金
属置換チタン酸リチウムを熱処理する方法である。この
熱処理によって、金属置換チタン酸リチウム結晶を緻密
にすることができる。熱処理の温度は、得られるチタン
酸リチウムの比表面積が１ｍ2 ／ｇとなる温度以下の温
度までであればよく、通常、２００〜８００℃程度であ
り、比表面積の大きなチタン酸リチウムを得るうえで
は、２５０〜７００℃の範囲が好ましく、３５０〜６５
０℃の範囲がより好ましい。Further, the present invention relates to a compound represented by the above general formula Li X M
This is a method of heat-treating a metal-substituted lithium titanate represented by Y Ti Z O 4 (where M is a metal having a valence of 2 or more and 0.5 ≦ (X + Y) / Z ≦ 2). By this heat treatment, the metal-substituted lithium titanate crystal can be made dense. The temperature of the heat treatment may be any temperature up to a temperature at which the specific surface area of the obtained lithium titanate becomes 1 m 2 / g, and is usually about 200 to 800 ° C. to obtain lithium titanate having a large specific surface area. Is preferably in the range of 250 to 700 ° C., and 350 to 65 ° C.
A range of 0 ° C. is more preferred.
【００１６】次に、本発明は、前記の金属置換チタン酸
リチウムからなるリチウム電池用電極であり、さらに
は、その電極を用いてなるリチウム電池である。リチウ
ム電池用電極は、本発明の金属置換チタン酸リチウムに
カーボンブラックなどの導電材とフッ素樹脂などのバイ
ンダとを加え、適宜成形して得られる。また、リチウム
電池は、前記の電極と対極と電解液とを備える。対極に
は、コバルト酸リチウム、ニッケル酸リチウム、マンガ
ン酸リチウム、五酸化バナジウム、カーボンなどの常用
の材料を用いることができる。また、電解液には、プロ
ピレンカーボネート、エチレンカーボネート、１、２−
ジメトキシエタンなどの溶媒にＬｉＰＦ6、ＬｉＣｌＯ
4 、ＬｉＣＦ3 ＳＯ3 、ＬｉＮ（ＣＦ3 ＳＯ2 ）2 、Ｌ
ｉＢＦ4 などのリチウム塩を溶解させたものなどの常用
の電解液を用いることができる。これらの材料をそれぞ
れ組み合わせてリチウム電池を構成することができる。Next, the present invention relates to an electrode for a lithium battery comprising the above-mentioned metal-substituted lithium titanate, and further to a lithium battery using the electrode. The electrode for a lithium battery is obtained by adding a conductive material such as carbon black and a binder such as a fluororesin to the metal-substituted lithium titanate of the present invention, and appropriately molding the resultant. Further, the lithium battery includes the above-mentioned electrode, counter electrode, and electrolyte. A common material such as lithium cobaltate, lithium nickelate, lithium manganate, vanadium pentoxide, and carbon can be used for the counter electrode. In addition, propylene carbonate, ethylene carbonate, 1,2-
LiPF 6 , LiClO in a solvent such as dimethoxyethane
4 , LiCF 3 SO 3 , LiN (CF 3 SO 2 ) 2 , L
A common electrolytic solution such as one in which a lithium salt such as iBF 4 is dissolved can be used. These materials can be combined to form a lithium battery.
【００１７】[0017]
【実施例】以下に本発明の実施例を示すが、本発明はこ
れらの実施例に限定されるものではない。EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited to these examples.
【００１８】実施例１ （１）チタン酸化合物の合成 ５リットルの４ツ口フラスコに、２８重量％のアンモニ
ア水９１１ｍｌと純水１３３９ｍｌとを入れ、攪拌下、
溶液の温度が１０〜１５℃になるように氷冷しながら、
１．２５モル／ｌの四塩化チタン水溶液２２５０ｍｌを
２時間かけて加え、その後、１時間熟成して沈殿物を得
た。熟成後のｐＨは８．８５であり、ＴｉＯ2 濃度は５
０ｇ／ｌであり、遊離水酸基濃度は０．５モル／ｌであ
った。Example 1 (1) Synthesis of titanate compound In a 5 liter four-necked flask, 911 ml of 28% by weight ammonia water and 1339 ml of pure water were placed, and stirred.
While cooling with ice so that the temperature of the solution becomes 10 to 15 ° C,
2250 ml of a 1.25 mol / l titanium tetrachloride aqueous solution was added over 2 hours, and then aged for 1 hour to obtain a precipitate. The pH after aging is 8.85 and the TiO 2 concentration is 5
It was 0 g / l, and the free hydroxyl group concentration was 0.5 mol / l.
【００１９】次に、前記の熟成後のスラリーに、３５重
量％の塩酸１９９ｍｌを純水３００ｍｌで希釈した塩酸
水溶液を１時間かけて添加してｐＨを５．５０に調整し
た後、そのｐＨを保持しながら１時間熟成した。その
後、沈殿物を濾過し、洗浄して、アンモニア、塩素イオ
ンを除去した後、得られた濾過ケーキをリパルプしてＴ
ｉＯ2 濃度５０ｇ／ｌのスラリーにした。次いで、氷冷
しながら、このスラリーに、３５重量％の塩酸２６ｍｌ
を純水１０４ｍｌで希釈した塩酸水溶液を１時間かけて
添加してｐＨを５．５０に調整した後、そのｐＨを保持
しながら１時間熟成し、次いで、沈殿物を濾過し、洗浄
して、チタン酸化合物を得た。Next, an aqueous solution of hydrochloric acid prepared by diluting 199 ml of 35% by weight hydrochloric acid with 300 ml of pure water was added to the aged slurry over 1 hour to adjust the pH to 5.50. Aged for 1 hour while holding. Thereafter, the precipitate was filtered and washed to remove ammonia and chloride ions, and the obtained filter cake was repulped to T
A slurry having an iO 2 concentration of 50 g / l was obtained. Then, while cooling with ice, 26 ml of 35% by weight hydrochloric acid was added to the slurry.
Was added over 1 hour to adjust the pH to 5.50, then aged for 1 hour while maintaining the pH, and then the precipitate was filtered and washed, A titanate compound was obtained.
【００２０】このようにして得られたチタン酸化合物少
量を５０℃の温度で乾燥して、その物性を調べた。その
結果、このチタン酸化合物は、微細な粒子の集合体（不
定形）であり、Ｘ線的に非晶質であった。また、化学分
析によると、その成分割合は、Ｔｉ４７．０重量％、Ｎ
Ｈ4 １．４４重量％、Ｃｌ ０．０７重量％であり、そ
の組成はＨ3.92（ＮＨ4 ）0.08ＴｉＯ4 であると推定さ
れる。さらに、ＤＳＣ分析によると、１１１℃で脱水
し、４４０℃でアナターゼに結晶化することがわかっ
た。A small amount of the titanate compound thus obtained was dried at a temperature of 50 ° C., and its physical properties were examined. As a result, this titanate compound was an aggregate (amorphous) of fine particles and was X-ray amorphous. According to the chemical analysis, the component ratio was 47.0% by weight of Ti, N
H 4 1.44 wt%, a Cl 0.07 wt%, the composition is estimated to H 3.92 (NH 4) a 0.08 TiO 4. Further, DSC analysis revealed that the polymer was dehydrated at 111 ° C. and crystallized into anatase at 440 ° C.
【００２１】（２）チタン酸リチウム水和物の合成 前記（１）で得られたチタン酸化合物をリパルプしてＴ
ｉＯ2 濃度５５．０２ｇ／ｌのスラリーを得た。このス
ラリーのｐＨは６．９０であり、導電率は３３０μＳ／
ｃｍであった。このスラリー３．６４リットルを５リッ
トルの４ツ口フラスコに仕込み、スラリーの温度が１０
〜１５℃になるように氷冷しながら、８４．９７ｇの水
酸化リチウム一水塩を純水３６０ｍｌに溶解した水溶液
を１時間かけて加え、その後、一時間熟成した。添加終
了後のスラリーのｐＨは１２．１であり、ＴｉＯ2 濃度
は５０ｇ／ｌであった。また、添加したリチウム化合物
は、Ｌｉ／Ｔｉモル比が０．８であった。次に、このよ
うにして得られたスラリーをオートクレーブに仕込み、
１９０℃の温度で２時間水熱処理した。水熱処理後のス
ラリーは、ペースト状に増粘しており、ｐＨは１３であ
り、アンモニア臭がした。次いで、水熱処理後のスラリ
ーを濾過した後、洗浄せずに５０℃の温度で乾燥して、
チタン酸リチウム水和物を得た。(2) Synthesis of lithium titanate hydrate The titanate compound obtained in the above (1) is repulped and T
A slurry having an iO 2 concentration of 55.02 g / l was obtained. The pH of this slurry was 6.90 and the conductivity was 330 μS /
cm. 3.64 liters of this slurry was charged into a 5 liter four-necked flask, and the temperature of the slurry was 10
An aqueous solution in which 84.97 g of lithium hydroxide monohydrate was dissolved in 360 ml of pure water was added over 1 hour while ice-cooling to -15 ° C, followed by aging for 1 hour. After completion of the addition, the pH of the slurry was 12.1, and the TiO 2 concentration was 50 g / l. The lithium compound added had a Li / Ti molar ratio of 0.8. Next, the slurry thus obtained was charged into an autoclave,
Hydrothermal treatment was performed at a temperature of 190 ° C. for 2 hours. The slurry after the hydrothermal treatment was thickened into a paste, had a pH of 13, and had an ammonia odor. Next, after filtering the slurry after the hydrothermal treatment, the slurry was dried at a temperature of 50 ° C. without washing,
Lithium titanate hydrate was obtained.
【００２２】このようにして得られたチタン酸リチウム
水和物の物性を調べた。その結果、このチタン酸リチウ
ム水和物は、電子顕微鏡観察により、長径が１μｍ、短
径が０．８μｍ、厚さ１６ｎｍ程度の極薄い板状形状を
有していることががわかった。比表面積は１０５．２ｍ
2 ／ｇであり、空隙量は０．３８６ｍｌ／ｇであった。
また、さらに、化学分析によると、その成分割合は、Ｔ
ｉ４５．０６量％、Ｌｉ５．３７重量％、ＮＨ4 ＜０．
０１重量％、Ｃｌ＜０．００５重量％であり、Ｘ線回折
からＬｉ1.33Ｔｉ1.67Ｏ4 ・Ｈ2 Ｏの存在が確認され
た。さらに、ＤＳＣ分析によると、２１５℃で結晶水を
放出してＬｉ1.33Ｔｉ1.67Ｏ4 に相転移し、３３７℃で
結晶化することがわかった。The properties of the lithium titanate hydrate thus obtained were examined. As a result, it was found from an electron microscope observation that this lithium titanate hydrate had an extremely thin plate-like shape with a major axis of 1 μm, a minor axis of 0.8 μm, and a thickness of about 16 nm. Specific surface area is 105.2m
2 / g, and the void volume was 0.386 ml / g.
Further, according to the chemical analysis, the component ratio is T
i45.06% by weight, Li 5.37% by weight, NH 4 <0.
01 wt%, Cl <0.005 wt%, and the presence of Li 1.33 Ti 1.67 O 4 .H 2 O was confirmed by X-ray diffraction. Furthermore, DSC analysis revealed that water of crystallization was released at 215 ° C., phase-transformed to Li 1.33 Ti 1.67 O 4 , and crystallized at 337 ° C.
【００２３】（３）チタン酸リチウムの合成 前記（２）で得られたチタン酸リチウム水和物を瑪瑙乳
鉢で粉砕した後、粉砕物１００ｇをアルミナ坩堝に計り
取り、５５０℃の温度に設定した電気炉に入れ、２時間
大気中で熱処理して、チタン酸リチウムを得た。(3) Synthesis of Lithium Titanate The lithium titanate hydrate obtained in the above (2) was pulverized in an agate mortar, and 100 g of the pulverized substance was weighed into an alumina crucible and set at a temperature of 550 ° C. It was placed in an electric furnace and heat-treated in the atmosphere for 2 hours to obtain lithium titanate.
【００２４】（４）コバルトアンモニウム錯塩溶液の作
成 塩化コバルト（ＣｏＣｌ2 ）０．２５モルおよび塩化ア
ンモニウム（ＮＨ4 Ｃｌ）０．１２５モルを水２００ｍ
ｌに溶解し、次いで８．９７規定のアンモニア水１９５
ｍｌを添加して、その後過酸化水素水を加えて酸化し
た。得られた溶液を水で５００ｍｌに希釈し、水不溶分
を濾過・分離して、Ｃｏ3+として０．５モル／ｌの濃度
のコバルトアンモニウム錯塩溶液を得た。(4) Preparation of Cobalt Ammonium Complex Salt Solution 0.25 mol of cobalt chloride (CoCl 2 ) and 0.125 mol of ammonium chloride (NH 4 Cl) were added to 200 m of water.
1), and then 195 of 8.97 normal ammonia water.
Then, the mixture was oxidized by adding aqueous hydrogen peroxide. The obtained solution was diluted to 500 ml with water, and the water-insoluble content was filtered and separated to obtain a cobalt ammonium complex salt solution having a concentration of 0.5 mol / l as Co 3+ .
【００２５】（５）イオン交換 前記（３）で得られたチタン酸リチウム５０ｇを５００
ｍｌの純水中に分散させ、この中に前記（４）の方法に
て作成したコバルトアンモニウム錯塩溶液２００ｍｌを
添加し１時間攪拌して、チタン酸リチウム中のリチウム
をコバルトでイオン交換し、次いで、ろ過、洗浄し、１
１０℃で乾燥して、本発明の金属（コバルト）置換チタ
ン酸リチウム（試料Ａ）を得た。(5) Ion exchange 50 g of the lithium titanate obtained in the above (3) was
The mixture was dispersed in 200 ml of pure water, and 200 ml of the cobalt ammonium complex salt solution prepared by the method (4) was added thereto, followed by stirring for 1 hour to ion-exchange lithium in lithium titanate with cobalt. , Filtration, washing, 1
After drying at 10 ° C., a metal (cobalt) -substituted lithium titanate of the present invention (sample A) was obtained.
【００２６】（６）熱処理 前記（５）で得られたコバルト置換チタン酸リチウムを
それぞれ、３００℃、４００℃、５００℃、６００℃の
温度に設定した電気炉に入れ、２時間大気中で熱処理し
て、本発明のコバルト置換チタン酸リチウム（試料Ｂ〜
Ｅ）を得た。(6) Heat treatment The cobalt-substituted lithium titanate obtained in the above (5) is placed in an electric furnace set to a temperature of 300 ° C., 400 ° C., 500 ° C., and 600 ° C., and heat-treated in the air for 2 hours. The cobalt-substituted lithium titanate of the present invention (samples B to
E) was obtained.
【００２７】このようにして得られたコバルト置換チタ
ン酸リチウム（試料Ａ〜Ｅ）の物性を調べた。その結
果、これらコバルト置換チタン酸リチウムは、電子顕微
鏡観察により、長径が０．２〜０．３μｍ、短径が０．
１６〜０．２４μｍ、厚さ２０〜４０ｎｍ程度の極薄い
板状形状を有する微粒子であることがわかった。試料Ａ
〜ＥのＢＥＴ式による比表面積は、各々、５６．２ｍ2
／ｇ、５３．６ｍ2 ／ｇ、５０．１ｍ2 ／ｇ、４５．２
ｍ2 ／ｇ、３２．６ｍ2 ／ｇであった。また、化学分析
の結果、試料Ａのコバルト：リチウム：チタンのモル比
は０．０３９：０．７４６：１．０００であった。さら
に、Ｘ線回折の回折図形から、試料Ａ〜Ｅはスピネル構
造を有し、他の相が認められないことから、リチウムを
コバルトで置換したコバルト置換チタン酸リチウムが単
相で得られたと考えられる。The physical properties of the cobalt-substituted lithium titanate (samples A to E) thus obtained were examined. As a result, these cobalt-substituted lithium titanates had a major axis of 0.2 to 0.3 μm and a minor axis of 0.3 μm, as observed by an electron microscope.
It was found that the fine particles had an extremely thin plate shape with a thickness of about 16 to 0.24 μm and a thickness of about 20 to 40 nm. Sample A
To E are 56.2 m 2 , respectively.
/G,53.6m 2 /g,50.1m 2 /g,45.2
It was m 2 /g,32.6m 2 / g. As a result of chemical analysis, the molar ratio of cobalt: lithium: titanium in Sample A was 0.039: 0.746: 1.000. Further, from the diffraction pattern of X-ray diffraction, Samples A to E have a spinel structure and no other phases were observed, so it was considered that cobalt-substituted lithium titanate in which lithium was substituted with cobalt was obtained in a single phase. Can be
【００２８】実施例２ （１）チタン酸化合物の合成 前記実施例１の（１）に記載された方法に準じて、チタ
ン酸化合物を得た。Example 2 (1) Synthesis of titanate compound A titanate compound was obtained according to the method described in (1) of Example 1 above.
【００２９】（２）チタン酸リチウム水和物の合成 前記（１）で得られたチタン酸化合物をリパルプしてＴ
ｉＯ2 濃度５６．２４ｇ／ｌのスラリーを得た。このス
ラリー１．４９４リットルと純水０．２０８リットルを
３リットルの４ツ口フラスコに仕込み、スラリーの温度
が１０〜２０℃になるように氷冷しながら、３．０７５
Ｎの水酸化リチウム溶液３２５ｍｌを１時間かけて加
え、次いで、８．７１Ｎのアンモニア水溶液０．２７６
リットルと純水０．１リットルを加えて１時間攪拌し、
熟成した。次に、このようにして得られたスラリーをオ
ートクレーブに仕込み、１７０℃の温度で４時間水熱処
理した。ついで、この水熱処理後のスラリーを濾過した
後、洗浄せずに５０℃の温度で乾燥して、チタン酸リチ
ウム水和物を得た。(2) Synthesis of lithium titanate hydrate The titanate compound obtained in the above (1) is repulped and T
A slurry having an iO 2 concentration of 56.24 g / l was obtained. 1.494 liters of this slurry and 0.208 liters of pure water are charged into a 3 liter four-necked flask, and cooled with ice so that the temperature of the slurry becomes 10 to 20 ° C., while 3.075 liters are added.
325 ml of a lithium hydroxide solution of N are added over 1 hour, and then 0.276 of an aqueous ammonia solution of 8.71 N is added.
Liters and 0.1 liter of pure water are added and stirred for 1 hour,
Matured. Next, the slurry thus obtained was charged into an autoclave and subjected to a hydrothermal treatment at a temperature of 170 ° C. for 4 hours. Then, the slurry after the hydrothermal treatment was filtered and dried at a temperature of 50 ° C. without washing to obtain lithium titanate hydrate.
【００３０】（３）チタン酸リチウムの合成 前記実施例１の（３）に記載された方法に準じて、チタ
ン酸リチウムを得た。(3) Synthesis of lithium titanate Lithium titanate was obtained according to the method described in (3) of Example 1.
【００３１】（４）ニッケルアンモニウム錯塩溶液の作
成 塩化ニッケル（ＮｉＣｌ2 ）０．２５モルを水２００ｍ
ｌに溶解し、次いで８．９７規定のアンモニア水２２３
ｍｌを添加し、次いで、水で５００ｍｌに希釈して、Ｎ
ｉ2+として０．５モル／ｌの濃度のニッケルアンモニウ
ム錯塩溶液を得た。(4) Preparation of nickel ammonium complex salt solution 0.25 mol of nickel chloride (NiCl 2 ) was added to 200 m of water.
1 and then 223 of 8.97 normal ammonia water.
ml, then dilute to 500 ml with water and add N
A nickel ammonium complex salt solution having a concentration of 0.5 mol / l as i 2+ was obtained.
【００３２】（５）イオン交換 前記（３）で得られたチタン酸リチウム５０ｇを５００
ｍｌの純水中に分散させ、この中に前記（４）の方法に
て作成したニッケルアンモニウム錯塩溶液２００ｍｌを
添加し１時間攪拌して、チタン酸リチウム中のリチウム
をニッケルでイオン交換し、次いで、ろ過し、１１０℃
で乾燥して、本発明の金属（ニッケル）置換チタン酸リ
チウム（試料Ｆ）を得た。(5) Ion exchange 50 g of the lithium titanate obtained in the above (3) was
Disperse in pure water of 200 ml, add 200 ml of the nickel ammonium complex salt solution prepared by the above method (4), stir for 1 hour, and ion exchange lithium in lithium titanate with nickel. , Filtered, 110 ° C
To obtain a metal (nickel) -substituted lithium titanate of the present invention (Sample F).
【００３３】（６）熱処理 前記（５）で得られたニッケル置換チタン酸リチウムを
それぞれ３００℃、４００℃、５００℃、６００℃の温
度に設定した電気炉に入れ、２時間大気中で熱処理し
て、本発明のニッケル置換チタン酸リチウム（試料Ｇ〜
Ｊ）を得た。(6) Heat treatment The nickel-substituted lithium titanate obtained in the above (5) is placed in an electric furnace set at a temperature of 300 ° C., 400 ° C., 500 ° C., and 600 ° C., respectively, and heat-treated in the air for 2 hours. The nickel-substituted lithium titanate of the present invention (samples G to
J) was obtained.
【００３４】このようにして得られたニッケル置換チタ
ン酸リチウム（試料Ｆ〜Ｊ）の物性を調べた。その結
果、これらニッケル置換チタン酸リチウムは、電子顕微
鏡観察により、長径が０．２〜０．３μｍ、短径が０．
１６〜０．２４μｍ、厚さ２０〜４０ｎｍ程度の極薄い
板状形状を有する微粒子であることがわかった。試料Ｆ
〜ＪのＢＥＴ式による比表面積は、各々、５１．２ｍ2
／ｇ、４８．９ｍ2 ／ｇ、４０．５ｍ2 ／ｇ、３８．９
ｍ2 ／ｇ、３３．１ｍ2 ／ｇであった。また、化学分析
の結果、試料Ｆのニッケル：リチウム：チタンのモル比
は０．０１８：０．７２５：１．０００であった。さら
に、Ｘ線回折の回折図形から、試料Ｆ〜Ｊはスピネル構
造を有し、他の相が認められないことから、リチウムを
ニッケルで置換したニッケル置換チタン酸リチウムが単
相で得られたと考えられる。The physical properties of the thus obtained nickel-substituted lithium titanate (Samples F to J) were examined. As a result, these nickel-substituted lithium titanates had a major axis of 0.2 to 0.3 μm and a minor axis of 0.2 to 0.3 μm, as observed by an electron microscope.
It was found that the fine particles had an extremely thin plate shape with a thickness of about 16 to 0.24 μm and a thickness of about 20 to 40 nm. Sample F
To J are 51.2 m 2 , respectively.
/G,48.9m 2 /g,40.5m 2 /g,38.9
It was m 2 /g,33.1m 2 / g. As a result of chemical analysis, the molar ratio of nickel: lithium: titanium of Sample F was 0.018: 0.725: 1.000. Further, from the diffraction pattern of the X-ray diffraction, Samples F to J have a spinel structure and no other phases were recognized, and it is considered that nickel-substituted lithium titanate in which lithium was substituted with nickel was obtained as a single phase. Can be
【００３５】前記の実施例１および２で得られた試料Ａ
〜Ｊを用いてリチウム電池用電極、さらにはリチウム電
池を製造したところ、所望の特性を有するものであるこ
とを確認した。Sample A obtained in Examples 1 and 2 above
To J, a lithium battery electrode and further a lithium battery were manufactured, and it was confirmed that they had desired characteristics.
【００３６】[0036]
【発明の効果】本発明は、２以上の原子価を有する金属
でリチウム成分の一部が置換された一般式ＬｉX ＭY Ｔ
ｉZ Ｏ4 （但し、Ｍは２以上の原子価を有する金属であ
って、０．５≦（Ｘ＋Ｙ）／Ｚ≦２）で表される金属置
換チタン酸リチウムであって、リチウムイオンのドー
プ、脱ドープをすみやかに行うことができるため、リチ
ウム電池用電極などの特性に優れたものである。According to the present invention, there is provided a compound represented by the general formula Li X MY T in which a lithium component is partially substituted with a metal having a valence of 2 or more.
i Z O 4 (where M is a metal having a valence of 2 or more and is a metal-substituted lithium titanate represented by 0.5 ≦ (X + Y) / Z ≦ 2), and doped with lithium ions Since it can be quickly de-doped, it has excellent characteristics such as an electrode for a lithium battery.
【００３７】また、本発明は、一般式ＬｉX ＴｉY Ｏ4
（但し、０．５≦Ｘ／Ｙ≦２）で表されるチタン酸リチ
ウムのリチウム成分の一部を２以上の原子価を有する金
属でイオン交換することにより効率よく、一般式ＬｉX
ＭY ＴｉZ Ｏ4 （但し、Ｍは２以上の原子価を有する金
属であって、０．５≦（Ｘ＋Ｙ）／Ｚ≦２）で表される
金属置換チタン酸リチウムを製造する方法である。The present invention also relates to a compound represented by the general formula Li x Ti YO 4
(Where 0.5 ≦ X / Y ≦ 2) By ion-exchanging a part of the lithium component of lithium titanate with a metal having a valence of 2 or more, the compound of the general formula Li X
M Y Ti Z O 4 (where, M is a metal with two or more valences, 0.5 ≦ (X + Y) / Z ≦ 2) is a method for producing a metal-substituted lithium titanate represented by .
【００３８】さらに、本発明は、前記の金属置換チタン
酸リチウムからなることを特徴とするリチウム電池用電
極であり、さらには、その電極を用いてなることを特徴
とするリチウム電池であって、優れた電池特性を有し、
一次電池または二次電池として有用なものである。Further, the present invention provides a lithium battery electrode comprising the above-mentioned metal-substituted lithium titanate, and a lithium battery comprising the electrode. Has excellent battery characteristics,
It is useful as a primary battery or a secondary battery.
【図１】実施例１で得られたコバルト置換チタン酸リチ
ウム（試料Ａ）の粒子形状を示す電子顕微鏡写真であ
る。FIG. 1 is an electron micrograph showing the particle shape of cobalt-substituted lithium titanate (sample A) obtained in Example 1.
【図２】実施例１で得られたコバルト置換チタン酸リチ
ウム（試料Ａ）のＸ線回折図形である。FIG. 2 is an X-ray diffraction pattern of the cobalt-substituted lithium titanate (sample A) obtained in Example 1.
【図３】実施例２で得られたニッケル置換チタン酸リチ
ウム（試料Ｆ）の粒子形状を示す電子顕微鏡写真であ
る。FIG. 3 is an electron micrograph showing the particle shape of nickel-substituted lithium titanate (sample F) obtained in Example 2.
【図４】実施例２で得られたニッケル置換チタン酸リチ
ウム（試料Ｆ）のＸ線回折図形である。FIG. 4 is an X-ray diffraction pattern of the nickel-substituted lithium titanate (sample F) obtained in Example 2.
Claims (12)
が２以上の原子価を有する金属で置換されていることを
特徴とする一般式ＬｉX ＭY ＴｉZ Ｏ4 （但し、Ｍは２
以上の原子価を有する金属であって、０．５≦（Ｘ＋
Ｙ）／Ｚ≦２）で表される金属置換チタン酸リチウム。1. A general formula Li X MY Ti Z O 4 (where M is 2), wherein a part of a lithium component of lithium titanate is substituted by a metal having a valence of 2 or more.
A metal having the above valence, wherein 0.5 ≦ (X +
Y) A metal-substituted lithium titanate represented by / Z ≦ 2).
ト、ニッケル、マンガン、バナジウム、鉄、ホウ素、ア
ルミニウム、珪素、ジルコニウム、ストロンチウム、マ
グネシウム及び錫からなる群より選ばれる少なくとも１
種の金属であることを特徴とする請求項１に記載の金属
置換チタン酸リチウム。2. The method according to claim 2, wherein the metal having two or more valences is at least one selected from the group consisting of cobalt, nickel, manganese, vanadium, iron, boron, aluminum, silicon, zirconium, strontium, magnesium and tin.
The metal-substituted lithium titanate according to claim 1, which is a kind of metal.
有することを特徴とする請求項１に記載の金属置換チタ
ン酸リチウム。3. The metal-substituted lithium titanate according to claim 1, having a specific surface area in the range of 1 to 300 m 2 / g.
項１に記載の金属置換チタン酸リチウム。4. The metal-substituted lithium titanate according to claim 1, which has a plate-like shape.
有することを特徴とする請求項１に記載の金属置換チタ
ン酸リチウム。5. The metal-substituted lithium titanate according to claim 1, having a longest particle diameter in the range of 0.1 to 50 μm.
≦Ｘ／Ｙ≦２）で表されるチタン酸リチウムのリチウム
成分の一部を２以上の原子価を有する金属でイオン交換
することを特徴とする一般式ＬｉX ＭY ＴｉZ Ｏ4 （但
し、Ｍは２以上の原子価を有する金属であって、０．５
≦（Ｘ＋Ｙ）／Ｚ≦２）で表される金属置換チタン酸リ
チウムの製造方法。6. A compound of the general formula Li x Ti YO 4 (provided that 0.5
≦ X / Y ≦ 2) A lithium ion represented by the general formula Li X MY Ti Z O 4 wherein a part of the lithium component of lithium titanate is ion-exchanged with a metal having a valence of 2 or more. , M is a metal having a valence of 2 or more, and 0.5
A method for producing a metal-substituted lithium titanate represented by ≦ (X + Y) / Z ≦ 2).
水系媒液中で反応させてチタン酸化合物を得る第１工
程、該チタン酸化合物とリチウム化合物とを水系媒液中
で反応させてチタン酸リチウム水和物を得る第２工程お
よび該チタン酸リチウム水和物を熱処理してチタン酸リ
チウムを得る第３工程とからなることを特徴とする請求
項６に記載の一般式ＬｉX ＴｉY Ｏ4 （但し、０．５≦
Ｘ／Ｙ≦２）で表されるチタン酸リチウムの製造方法。7. A first step of reacting a titanium compound with an ammonium compound in an aqueous medium to obtain a titanate compound, and reacting the titanate compound with a lithium compound in an aqueous medium to form a lithium titanate solution. formula Li X Ti Y O 4 according to claim 6, characterized in that and a third step of obtaining a lithium titanate is heat treated a second step and lithium hydrate titanate obtain hydrate ( However, 0.5 ≦
X / Y ≦ 2) a method for producing lithium titanate.
は２以上の原子価を有する金属であって、０．５≦（Ｘ
＋Ｙ）／Ｚ≦２）で表される金属置換チタン酸リチウム
を熱処理することを特徴とする請求項６に記載の金属置
換チタン酸リチウムの製造方法。8. The general formula Li X MY Ti Z O 4 (where M
Is a metal having a valence of 2 or more, and 0.5 ≦ (X
The method for producing a metal-substituted lithium titanate according to claim 6, wherein the metal-substituted lithium titanate represented by (+ Y) / Z ≦ 2) is heat-treated.
化合物とを水系媒液中で水熱処理してチタン酸リチウム
水和物を得る工程であることを特徴とする請求項７に記
載のチタン酸リチウムの製造方法。9. The titanium according to claim 7, wherein the second step is a step of hydrothermally treating the titanate compound and the lithium compound in an aqueous medium to obtain lithium titanate hydrate. Method for producing lithium oxide.
ことを特徴とする請求項９に記載のチタン酸リチウムの
製造方法。10. The method for producing lithium titanate according to claim 9, wherein the hydrothermal treatment is performed in the presence of ammonia.
チウムからなることを特徴とするリチウム電池用電極。11. An electrode for a lithium battery, comprising the metal-substituted lithium titanate according to claim 1.
ことを特徴とするリチウム電池。12. A lithium battery using the electrode according to claim 11.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9076635A JPH10251020A (en) | 1997-03-11 | 1997-03-11 | Metal substituted lithium titanate, its production and lithium battery using the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9076635A JPH10251020A (en) | 1997-03-11 | 1997-03-11 | Metal substituted lithium titanate, its production and lithium battery using the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH10251020A true JPH10251020A (en) | 1998-09-22 |
Family
ID=13610845
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9076635A Pending JPH10251020A (en) | 1997-03-11 | 1997-03-11 | Metal substituted lithium titanate, its production and lithium battery using the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH10251020A (en) |
Cited By (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003030283A1 (en) * | 2001-10-02 | 2003-04-10 | Valence Technology, Inc. | Lithium cell based on lithiated transition metal titanates |
| US6706445B2 (en) | 2001-10-02 | 2004-03-16 | Valence Technology, Inc. | Synthesis of lithiated transition metal titanates for lithium cells |
| US6720112B2 (en) | 2001-10-02 | 2004-04-13 | Valence Technology, Inc. | Lithium cell based on lithiated transition metal titanates |
| JP2005504693A (en) * | 2000-12-05 | 2005-02-17 | ハイドロ−ケベック | Particle groups mainly composed of Li4Ti5O12, Li (4-α) ZαTi5O12, or Li4ZβTi (5-β) O12, a method for obtaining these particle groups, and a method for using these particle groups in an electrochemical device |
| JP2005063673A (en) * | 2003-08-08 | 2005-03-10 | Sanyo Electric Co Ltd | Nonaqueous electrolyte secondary battery |
| JP2006040557A (en) * | 2004-07-22 | 2006-02-09 | Hitachi Maxell Ltd | Organic electrolyte secondary battery |
| JP2006526255A (en) * | 2003-05-09 | 2006-11-16 | ユミコア | Negative electrode for lithium battery |
| JP2008517419A (en) * | 2004-08-30 | 2008-05-22 | トヨタ モーター エンジニアリング アンド マニュファクチャリング ノース アメリカ インコーポレイテッド | Improving charge / discharge cycle stability of lithium ion batteries with molten salt electrolytes |
| JP2009542562A (en) * | 2006-06-05 | 2009-12-03 | エイ１２３ システムズ インコーポレイテッド | Alkali metal titanates and methods for their synthesis |
| WO2010137582A1 (en) * | 2009-05-26 | 2010-12-02 | 石原産業株式会社 | Lithium titanate, process for production of same, and electrode active material and electricity storage device each comprising same |
| CN101967009A (en) * | 2010-11-09 | 2011-02-09 | 中国海洋石油总公司 | Method for preparing lithium titanate cathode material for lithium ion power batteries |
| US8053115B2 (en) | 2005-03-30 | 2011-11-08 | Gs Yuasa International Ltd. | Active material for lithium ion battery having Mg-containing lithium titanate and lithium ion battery |
| WO2012029697A1 (en) | 2010-08-31 | 2012-03-08 | 戸田工業株式会社 | Lithium titanate particulate powder and production method for same, mg-containing lithium titanate particulate powder and production method for same, negative electrode active material particulate powder for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery |
| JP4957911B2 (en) * | 2005-03-30 | 2012-06-20 | 株式会社Ｇｓユアサ | Lithium ion battery active material and lithium ion battery comprising Al-containing lithium titanate |
| JP2012131688A (en) * | 2010-12-20 | 2012-07-12 | Industrial Technology Research Inst | Material of phosphorus-doped lithium titanium oxide with spinel structure, and method of manufacturing the same |
| WO2012111293A1 (en) * | 2011-02-15 | 2012-08-23 | パナソニック株式会社 | Negative electrode active material for lithium ion secondary battery, and manufacturing method for same |
| JP2012221953A (en) * | 2011-04-05 | 2012-11-12 | Samsung Sdi Co Ltd | Negative electrode active material, method for manufacturing the same, and lithium secondary battery containing the same |
| JP2013062212A (en) * | 2011-09-15 | 2013-04-04 | Toyota Motor Corp | Negative electrode active material, negative electrode, and battery |
| CN103199231A (en) * | 2012-01-04 | 2013-07-10 | 罗伯特·博世有限公司 | Iron-doped lithium titanate as a cathode material |
| JP2014037345A (en) * | 2008-06-03 | 2014-02-27 | Sued-Chemie Ip Gmbh & Co Kg | Method for producing complex oxide, method of producing and using lithium titanate spinel |
| WO2014073700A1 (en) * | 2012-11-12 | 2014-05-15 | 国立大学法人九州大学 | Positive electrode active material for lithium battery, and lithium battery comprising said positive electrode active material for lithium battery |
| US9269948B2 (en) | 2010-11-16 | 2016-02-23 | Toyota Jidosha Kabushiki Kaisha | Positive electrode active material, process for producing same, and lithium secondary battery using same |
| WO2018110708A1 (en) | 2016-12-16 | 2018-06-21 | 宇部興産株式会社 | Lithium titanate powder and active material ingredient for electrode of power storage device, and electrode sheet and power storage device using same |
| CN110323433A (en) * | 2019-07-10 | 2019-10-11 | 银隆新能源股份有限公司 | A kind of lithium titanate composite material and preparation method thereof, lithium ion battery and preparation method thereof |
-
1997
- 1997-03-11 JP JP9076635A patent/JPH10251020A/en active Pending
Cited By (43)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010280560A (en) * | 2000-12-05 | 2010-12-16 | Hydro Quebec | PARTICLE ASSEMBLAGE INCLUDING Li4Ti5O12, Li(4-alpha)ZalphaTi5O12 OR Li4ZbetaTi(5-beta)O12 AS MAIN COMPONENT, METHOD FOR OBTAINING THE SAME, AND METHOD FOR APPLYING THE PARTICLE ASSEMBLAGE IN ELECTROCHEMICAL EQUIPMENT |
| JP2005504693A (en) * | 2000-12-05 | 2005-02-17 | ハイドロ−ケベック | Particle groups mainly composed of Li4Ti5O12, Li (4-α) ZαTi5O12, or Li4ZβTi (5-β) O12, a method for obtaining these particle groups, and a method for using these particle groups in an electrochemical device |
| US9077031B2 (en) | 2000-12-05 | 2015-07-07 | Hydro-Quebec | Li4Ti5O12, Li(4-α)ZαTi5O12or Li4ZβTi(5-β)O12 particles, processes for obtaining same and their use in electrochemical generators |
| US9559356B2 (en) | 2000-12-05 | 2017-01-31 | Hydro-Quebec | Li4Ti5O12, Li(4-α)ZαTi5O12 or Li4ZβTi(5-β)O12 particles, processes for obtaining same and use as electrochemical generators |
| US10734647B2 (en) | 2000-12-05 | 2020-08-04 | Hydro-Quebec | Li4Ti5O12, Li(4-α)ZαTi5O12 or Li4ZβTi(5-β)O12, particles, processes for obtaining same and use as electrochemical generators |
| US8114469B2 (en) | 2000-12-05 | 2012-02-14 | Hydro-Quebec | Li4Ti5O12, Li(4-α)ZαTi5O12 or Li4ZβTi(5-βO12 particles, processes for obtaining same and use as electrochemical generators |
| JP4790204B2 (en) * | 2000-12-05 | 2011-10-12 | ハイドロ−ケベック | Particle groups mainly composed of Li4Ti5O12, Li (4-α) ZαTi5O12, or Li4ZβTi (5-β) O12, a method for obtaining these particle groups, and a method for using these particle groups in an electrochemical device |
| US6706445B2 (en) | 2001-10-02 | 2004-03-16 | Valence Technology, Inc. | Synthesis of lithiated transition metal titanates for lithium cells |
| US6720112B2 (en) | 2001-10-02 | 2004-04-13 | Valence Technology, Inc. | Lithium cell based on lithiated transition metal titanates |
| WO2003030283A1 (en) * | 2001-10-02 | 2003-04-10 | Valence Technology, Inc. | Lithium cell based on lithiated transition metal titanates |
| JP4844892B2 (en) * | 2003-05-09 | 2011-12-28 | ユミコア | Negative electrode active material for lithium secondary battery and lithium secondary battery using the same |
| JP2006526255A (en) * | 2003-05-09 | 2006-11-16 | ユミコア | Negative electrode for lithium battery |
| JP2005063673A (en) * | 2003-08-08 | 2005-03-10 | Sanyo Electric Co Ltd | Nonaqueous electrolyte secondary battery |
| JP2006040557A (en) * | 2004-07-22 | 2006-02-09 | Hitachi Maxell Ltd | Organic electrolyte secondary battery |
| JP2008517419A (en) * | 2004-08-30 | 2008-05-22 | トヨタ モーター エンジニアリング アンド マニュファクチャリング ノース アメリカ インコーポレイテッド | Improving charge / discharge cycle stability of lithium ion batteries with molten salt electrolytes |
| JP4957911B2 (en) * | 2005-03-30 | 2012-06-20 | 株式会社Ｇｓユアサ | Lithium ion battery active material and lithium ion battery comprising Al-containing lithium titanate |
| US8053115B2 (en) | 2005-03-30 | 2011-11-08 | Gs Yuasa International Ltd. | Active material for lithium ion battery having Mg-containing lithium titanate and lithium ion battery |
| JP4957912B2 (en) * | 2005-03-30 | 2012-06-20 | 株式会社Ｇｓユアサ | Lithium ion battery active material and lithium ion battery comprising Mg-containing lithium titanate |
| JP2009542562A (en) * | 2006-06-05 | 2009-12-03 | エイ１２３ システムズ インコーポレイテッド | Alkali metal titanates and methods for their synthesis |
| KR101410844B1 (en) * | 2006-06-05 | 2014-06-23 | 에이일이삼 시스템즈 인코포레이티드 | Alkali metal titanates and methods for their synthesis |
| US9187336B2 (en) | 2008-06-03 | 2015-11-17 | Sued-Chemie Ip Gmbh & Co. Kg | Process for the preparation of lithium titanium spinel and its use |
| JP2014037345A (en) * | 2008-06-03 | 2014-02-27 | Sued-Chemie Ip Gmbh & Co Kg | Method for producing complex oxide, method of producing and using lithium titanate spinel |
| CN102428031A (en) * | 2009-05-26 | 2012-04-25 | 石原产业株式会社 | Lithium titanate, process for production of same, and electrode active material and electricity storage device each comprising same |
| JP5726074B2 (en) * | 2009-05-26 | 2015-05-27 | 石原産業株式会社 | Lithium titanate, method for producing the same, electrode active material using the same, and electricity storage device |
| US9452940B2 (en) | 2009-05-26 | 2016-09-27 | Ishihara Sangyo Kaisha, Ltd. | Lithium titanate, electrode active material and electricity storage device each comprising the same |
| US9126847B2 (en) | 2009-05-26 | 2015-09-08 | Ishihara Sangyo Kaisha, Ltd. | Lithium titanate, electrode active material and electricity storage device each comprising the same |
| WO2010137582A1 (en) * | 2009-05-26 | 2010-12-02 | 石原産業株式会社 | Lithium titanate, process for production of same, and electrode active material and electricity storage device each comprising same |
| WO2012029697A1 (en) | 2010-08-31 | 2012-03-08 | 戸田工業株式会社 | Lithium titanate particulate powder and production method for same, mg-containing lithium titanate particulate powder and production method for same, negative electrode active material particulate powder for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery |
| CN101967009A (en) * | 2010-11-09 | 2011-02-09 | 中国海洋石油总公司 | Method for preparing lithium titanate cathode material for lithium ion power batteries |
| US9269948B2 (en) | 2010-11-16 | 2016-02-23 | Toyota Jidosha Kabushiki Kaisha | Positive electrode active material, process for producing same, and lithium secondary battery using same |
| JP2012131688A (en) * | 2010-12-20 | 2012-07-12 | Industrial Technology Research Inst | Material of phosphorus-doped lithium titanium oxide with spinel structure, and method of manufacturing the same |
| US9065148B2 (en) | 2011-02-15 | 2015-06-23 | Panasonic Intellectual Property Management Co., Ltd. | Negative electrode active material for lithium ion secondary battery and method for producing the same |
| JP5148781B2 (en) * | 2011-02-15 | 2013-02-20 | パナソニック株式会社 | Negative electrode active material for lithium ion secondary battery and method for producing the same |
| WO2012111293A1 (en) * | 2011-02-15 | 2012-08-23 | パナソニック株式会社 | Negative electrode active material for lithium ion secondary battery, and manufacturing method for same |
| JP2012221953A (en) * | 2011-04-05 | 2012-11-12 | Samsung Sdi Co Ltd | Negative electrode active material, method for manufacturing the same, and lithium secondary battery containing the same |
| US8945771B2 (en) | 2011-09-15 | 2015-02-03 | Toyota Jidosha Kabushiki Kaisha | Negative-electrode active material comprising a pseudobrookite-structured compound, negative electrode and battery |
| JP2013062212A (en) * | 2011-09-15 | 2013-04-04 | Toyota Motor Corp | Negative electrode active material, negative electrode, and battery |
| CN103199231A (en) * | 2012-01-04 | 2013-07-10 | 罗伯特·博世有限公司 | Iron-doped lithium titanate as a cathode material |
| JP2014096333A (en) * | 2012-11-12 | 2014-05-22 | Kyushu Univ | Positive electrode active material for lithium battery and lithium battery containing the same |
| WO2014073700A1 (en) * | 2012-11-12 | 2014-05-15 | 国立大学法人九州大学 | Positive electrode active material for lithium battery, and lithium battery comprising said positive electrode active material for lithium battery |
| WO2018110708A1 (en) | 2016-12-16 | 2018-06-21 | 宇部興産株式会社 | Lithium titanate powder and active material ingredient for electrode of power storage device, and electrode sheet and power storage device using same |
| CN110323433A (en) * | 2019-07-10 | 2019-10-11 | 银隆新能源股份有限公司 | A kind of lithium titanate composite material and preparation method thereof, lithium ion battery and preparation method thereof |
| CN110323433B (en) * | 2019-07-10 | 2022-12-20 | 银隆新能源股份有限公司 | Lithium titanate composite material and preparation method thereof, lithium ion battery and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH10251020A (en) | Metal substituted lithium titanate, its production and lithium battery using the same | |
| JP3894614B2 (en) | Method for producing lithium titanate | |
| EP1483206B1 (en) | Process for making nano-sized and sub-micron-sized lithium-transition metal oxides | |
| US20200365889A1 (en) | Manganese spinel doped with magnesium, cathode material comprising the same, method for preparing thereof and lithium ion battery comprising such spinel | |
| JP2729176B2 (en) | Method for producing LiM3 + O2 or LiMn2O4 and LiNi3 + O2 for cathode material of secondary battery | |
| Pereira-Ramos | Electrochemical properties of cathodic materials synthesized by low-temperature techniques | |
| JP3894615B2 (en) | Lithium titanate, method for producing the same, and lithium battery using the same | |
| JP2013503102A (en) | Method for preparing lithium metal oxides using fluidized bed technology | |
| KR101548383B1 (en) | 2 titanium oxide compound for use in electrode and lithium secondary battery comprising the same | |
| KR20140047669A (en) | Production of nanostructured li4ti5o12 with superior high rate performance | |
| CN104781186A (en) | Layered and spinel lithium titanates and processes for preparing same | |
| US6699456B1 (en) | Method for producing lithium metal oxides | |
| US6054110A (en) | Process for producing lithium-cobalt composite oxide | |
| JP2003292322A (en) | Method for manufacturing active substance for positive electrode of lithium ion secondary battery | |
| JP6243932B2 (en) | Method for producing titanium niobium oxide, and method for producing titanium niobium oxide negative electrode active material using titanium niobium oxide obtained therefrom | |
| JP2002274849A (en) | Lithium titanate, production method therefor and its use | |
| US6706443B1 (en) | Process for preparing lithium manganese oxides | |
| KR101262054B1 (en) | 2D NANOSTRUCTURED Li4Ti5O12, SYNTHETIC METHOD THEREOF AND ELECTRODE MATERIAL COMPRISING SAID 2D NANOSTRUCTURED Li4Ti5O12 | |
| Monti et al. | Microwaves as a synthetic route for preparing electrochemically active TiO2 nanoparticles | |
| CN113348150B (en) | Titanium oxide, method for producing titanium oxide, and lithium secondary battery using electrode active material containing titanium oxide | |
| JPH10279315A (en) | Production of lithium-cobalt multiple oxide | |
| JP2001526620A (en) | Lithium metal oxide | |
| JPH09270260A (en) | Lithium nickelate as positive electrode active material of lithium secondary battery and manufacture thereof | |
| CN108400295B (en) | Silver-coated spinel-type LiMn2O4Material and method for the production thereof | |
| Kimijima et al. | Phase-selective hydrothermal synthesis of hydrous lithium titanates nanoparticles as a precursor to Li4Ti5O12 anode material for lithium ion rechargeable batteries |