JP3658314B2 - Electrolytes - Google Patents

Description

【００２３】
式中、ｎは５〜１００、好ましくは５〜５０の整数である。ｍは１〜５０、好ましくは１〜１０の整数である。ｘは０．１〜０．９を示す。
【００２４】
次に、本発明に用いられる液晶化合物は、好ましくは下記一般式（Ｉ）〜（ＩＩ）で示される化合物である。
【００２５】
【化２】

【００２６】
一般式（Ｉ）において、Ｒ₁，Ｒ₂，Ｒ₃，Ｒ₄，Ｒ₅，Ｒ₆はそれぞれ独立に２つ以上のＯＣＨ₂ＣＨ₂セグメントあるいはＯＣＨ₂ＣＨ₂ＣＨ₂セグメントから構成され、末端部分に炭素原子数１〜２０の分岐状または直鎖状のアルキル基がついた側鎖を示す。但し、該アルキル基中の水素原子はフッ素原子に置き換わっていてもよく、また１つ以上のメチレン基はＯ、ＣＯ、−ＣＨ＝ＣＨ−、−Ｃ≡Ｃ−またはエポキシ基に置き換わっていてもよい。
【００２７】
前記一般式（Ｉ）において、好ましくはＲ₁，Ｒ₂，Ｒ₃，Ｒ₄，Ｒ₅，Ｒ₆がそれぞれ独立に（ＯＣＨ₂ＣＨ₂）_nＯＲ₇または（ＯＣＨ₂ＣＨ₂ＣＨ₂）_nＯＲ₇である。式中ｎは１〜２０の整数であり、Ｒ₇は炭素原子数４〜２０の分岐状または直鎖状のアルキル基を示す。該アルキル基中の水素原子はフッ素原子に置き換わっていてもよく、また１つ以上のメチレンはＯ、ＣＯ、−ＣＨ＝ＣＨ−、−Ｃ≡Ｃ−またはエポキシ基に置き換わっていてもよい。
【００２８】
【化３】

【００２９】
一般式（ＩＩ）において、ＡはＡ１−Ｂ１−Ａ２−Ｂ２−Ａ３−Ｂ３−Ａ４−Ｂ４−Ａ５−Ｂ５−Ａ６を示す。
Ａ１，Ａ２，Ａ３は１，４−フェニレン（１つ以上のＣＨはＣＦまたはＮに置き換わっていてもよい）または１，４−シクロヘキシレンを示す。
Ａ４，Ａ５，Ａ６は単結合または１，４−フェニレン（１つ以上のＣＨはＣＦまたはＮに置き換わっていてもよい）または１，４−シクロヘキシレンを示す。
Ｂ１，Ｂ２、Ｂ３，Ｂ４，Ｂ５は単結合または−ＣＨ₂Ｏ−，−ＯＣＨ₂−，−ＣＯＯ−，−ＯＯＣ−を示す。
Ｘは−ＣＨ₂ＣＨ₂Ｏ−または−ＣＨＣＨ₃ＣＨ₂Ｏ−を示す。
Ｙは−ＯＣＨ₂ＣＨ₂−または−ＯＣＨ₂ＣＨＣＨ₃−を示す。
Ｒ₁₁、Ｒ₁₂はそれぞれ独立に炭素原子数が１から１００までの直鎖状または分岐状のアルキル基であり、該アルキル基中の１つ以上のメチレンは−Ｏ−，−ＣＯ−，−Ｓ−，−ＣＨ＝ＣＨ−，−Ｃ≡Ｃ−に置き換わっていてもよい。また該アルキル基中の水素原子はフッ素原子に置き換わっていてもよい。
ｍ１、ｎ１は３から２５までの整数を示す。光学活性化合物でもよい。
【００３０】
また、好ましくは一般式（ＩＩ）において、化合物のＡが下記一般式（ＩＩａ）〜（ＩＩｉ）で示される化合物である。
式中、ｚはそれぞれ独立に０〜４の整数を示す。
【００３１】
【化４】

【００３２】
【化５】

以下、本発明の電解質に用いられる液晶化合物の具体的な構造式を表１〜１４に示す。但し、本発明はこれらのみに限定されるものではない。尚、表中の略記は以下の基を示す。
【００３３】
【化６】

【００３４】
【化７】

【００３５】
【表１】

【００３６】
【表２】

【００３７】
【表３】

【００３８】
【表４】

【００３９】
【表５】

【００４０】
【表６】

【００４１】
【表７】

【００４２】
【表８】

【００４３】
【表９】

【００４４】
【表１０】

【００４５】
【表１１】

【００４６】
【表１２】

【００４７】
【表１３】

【００４８】
【表１４】

【００４９】
次に、本発明の電解質の応用例として、二次電池について説明する。
図１は二次電池の模式的な構成例である。４１、４２はそれぞれ負、正の電極である。４３が電解質層であって、この層を通路として特定極性のイオンが負電極から正電極へ、あるいは正電極から負電極へ伝達される。上記負および正の電極はイオンの放出と吸収の機能、外部デバイスとの連携機能（例えば電子伝導性機能）、機械的な支持機能等、多義に渉る機能が要求されることから通常機能分離された複数の部材からなる複合体となる場合が多い。
【００５０】
負電極４１は外部回路との電子的接続機能を兼ねた銅、アルミニウム、金、白金などの電子伝導性支持体４１１に負極活物質４１２をコーティングしたものが用いられる。或いは支持体としての機能をかねた負極活物質を用いることもできる。負極活物質材料としてはＬｉイオン、Ｎａイオン、Ｋイオン等のアルカリイオン、アルカリ土類イオン、水素イオン等のカチオンを放出する能力を有する材料として、金属材料のなかからリチウム金属箔、リチウム−アルミニウム合金等が、高分子材料のなかから好ましくはｎ型にドープされたポリアセチレン、ポリチオフェン、ポリｐ−フェニレン、ポリアセン等およびその誘導体が、また炭素系材料のなかからグラファイト（黒鉛）、ピッチ、コークス、有機高分子の焼結体、あるいはこれらの材料と有機高分子の複合体が適宜選択的に用いられる。
【００５１】
正電極４２は、外部回路との電子的接続機能を兼ねた銅、アルミニウム、金、白金などの電子伝導性支持体４２１に正極活物質４２２をコーティングしたものが用いられる。或いは支持体としての機能をかねた正極活物質を用いることもできる。正極活物質材料としては無機材料のなかからコバルト、バナジウム、チタン、モリブデン、鉄、マンガンなど遷移金属のカルコゲン化合物及び酸化物、さらにこれらとリチウムの複合体が、炭素系材料のなかからグラファイト、弗化カーボンなど一連の層状化合物、あるいはこれらの材料と有機高分子の複合体が、高分子材料のなかから好ましくはｐ型またはｎ型にドープされたポリアセチレン、ポリアニリン、ポリピロール、ポリチオフェン、ポリｐ−フェニレン、ポリアセン、ポリフタロシアニン、ポリピリジン等、およびこれらの誘導体が適宜選択的に用いられる。
【００５２】
【実施例】
以下、実施例により本発明について更に詳細に説明するが、本発明はこれらの実施例に限定されるものではない。
【００５３】
合成例１
２，３，６，７，１０，１１−ヘキサ（２−ヘキシルオキシエチルオキシ）トリフェニレン（例示化合物Ｔ−６）の製造
（１）ｐ−トルエンスルホン酸２−ヘキシルオキシエチルの製造
反応容器に２−ヘキシルオキシエタノール３．２９ｇ（２２．５ｍｍｏｌ）とピリジン５．３３ｇ（６７．５ｍｍｏｌ）を入れ、それに氷浴中、ｐ−トルエンスルホン酸クロリド４．７２ｇ（２４．７ｍｍｏｌ）を加え、１時間撹拌した後、室温で更に３時間撹拌した。反応終了後、３Ｎ−ＨＣｌを加え酸性とした後、トルエンで２回抽出した。抽出液を水で洗浄した後、無水硫酸ナトリウムを加え乾燥した。溶媒を留去した後、シリカゲルカラムクロマトグラフィー（溶離溶媒：トルエン／酢酸エチル＝１０／１）により精製し、ｐ−トルエンスルホン酸２−ヘキシルオキシエチル６．４５ｇ（２１．５ｍｍｏｌ）を得た。収率９５％
【００５４】
（２） ２，３，６，７，１０，１１−ヘキサ（２−ヘキシルオキシエチルオキシ）トリフェニレンの製造
反応容器に乾燥Ｎ，Ｎ−ジメチルホルムアミド（ＤＭＦ）１５ｍｌと水素化ナトリウム（６０％ ｉｎ ｏｉｌ（鉱油））０．７７ｇ（１９．３ｍｍｏｌ）を入れ、それに水浴中、２，３，６，７，１０，１１−ヘキサヒドロキシトリフェニレン０．９２ｇ（２．８４ｍｍｏｌ）を加え１時間撹拌した。その後、ｐ−トルエンスルホン酸２−ヘキシルオキシエチル６．３ｇ（２１．０ｍｍｏｌ）と乾燥ＤＭＦ５ｍｌの混合液を滴下し、８０℃で５時間撹拌した。反応終了後、水を加えトルエンで２回抽出した。抽出液を水で洗浄した後、無水硫酸ナトリウムを加え乾燥した。溶媒を留去した後、シリカゲルカラムクロマトグラフィー（溶離溶媒：トルエン／酢酸エチル＝５／１）を２回行い精製し、２，３，６，７，１０，１１−ヘキサ（２−ヘキシルオキシエチルオキシ）トリフェニレン１．１５ｇ（１．０ｍｍｏｌ）を得た。収率３５％
【００５５】
得られた化合物のＤＳＣによる相転移温度を以下に示す。
昇温過程
Ｃｒｙ（−２４℃）Ｘｌ（１７℃）Ｘ２（２９℃）Ｄｈ（８４℃）Ｉｓｏ
冷却過程
Ｉｓｏ（８１℃）Ｄｈ（１６℃）Ｘ２（５℃）Ｘｌ（＜−５０℃）Ｃｒｙ
Ｃｒｙ：結晶相、Ｘ１，Ｘ２：未同定の相、Ｄｈ：ディスコチックカラムナー相、Ｉｓｏ：等方相
【００５６】
実施例１
次に合成した２，３，６，７，１０，１１−ヘキサ（２−ヘキシルオキシエチルオキシ）トリフェニレン６５．６ｍｇ（０．０６ｍｍｏｌ）に乾燥ジクロロメタンｌｍｌを加え、撹拌し完全に溶解させた。それにポリエチレンオキシド（重量平均分子量４００）２．４ｍｇ、過塩素酸リチウム３．１９ｍｇ（０．０３０ｍｍｏｌ）と乾燥エタノール１ｍｌを加え２時間撹拌した。完全に溶解していることを確認した後、溶媒を留去し、減圧乾燥して電解質Ａを得た。
【００５７】
得られた電解質Ａの相転移温度を示す。
昇温過程
Ｃｒｙ（＜−５０℃）Ｘｌ（２２℃）Ｘ２（２９℃）Ｄｈ（８８℃）Ｉｓｏ
冷却過程
Ｉｓｏ（８６℃）Ｄｈ（１０℃）Ｘ２（＜−５０℃）Ｘｌ（＜−５０℃）Ｃｒｙ
Ｃｒｙ：結晶相、Ｘ１，Ｘ２：未同定の相、Ｄｈ：ディスコチックカラムナー相、Ｉｓｏ：等方相
【００５８】
実施例２
２，３，６，７，１０，１１−ヘキサ（２−ヘキシルオキシエチルオキシ）トリフェニレン６５．６ｍｇ（０．０６ｍｍｏｌ）に乾燥ジクロロメタン１ｍｌを加え、撹拌し完全に溶解させた。それにポリエチレンオキシド（重量平均分子量３０００）４．８ｍｇ、過塩素酸リチウム３．１９ｍｇ（０．０３０ｍｍｏｌ）と乾燥エタノールｌｍｌを加え２時間撹拌した。完全に溶解していることを確認した後、溶媒を留去し、減圧乾燥して電解質Ｂを得た。
【００５９】
得られた電解質Ｂの相転移温度を示す。
昇温過程
Ｃｒｙ（＜−５０℃）Ｘｌ（２８℃）Ｘ２（３１℃）Ｄｈ（９０℃）Ｉｓｏ
冷却過程
Ｉｓｏ（８８℃）Ｄｈ（１１℃）Ｘ２（＜−５０℃）Ｘｌ（＜−５０℃）Ｃｒｙ
Ｃｒｙ：結晶相、Ｘ１，Ｘ２：未同定の相、Ｄｈ：ディスコチックカラムナー相、Ｉｓｏ：等方相
【００６０】
実施例３
透明電極として厚さ７００ÅのＩＴＯ膜を形成した厚さ１．１ｍｍの一対のガラス基板を用意した。該基板の透明電極上に、一方の基板上にスペーサーとして、平均粒径２．４μｍのシリカビーズを散布し、均一なセルギャップのセルＡを作製した。このセルに実施例１で調製した電解質Ａを等方性液体状態で注入し、等方相から２０℃／ｈでディスコチックカラムナー相を示す温度まで冷却した。このセルを偏光顕微鏡でクロスニコル下、テクスチャーを観察した所、暗視野が得られ、ディスコチックカラムナー相がホメオトロピック配向をしていることがわかった。
【００６１】
次に０．００１〜１００ｋＨｚ、１０ｍＶの交流電圧を印加した時の電流を測定して複素インピーダンスを測定し、イオン伝導率を算出した。その結果を以下に示す。
測定温度 イオン伝導率
５０℃ １．１×１０^-7Ｓ／ｃｍ
【００６２】
次に、平均粒径２．４μｍのシリカビーズの代わりに、平均粒径２０μｍのシリカビーズを用いる以外は同様の手法によりセルＢを作成し、電解質Ａを注入し、偏光顕微鏡でテクスチャーを観察した所、マルチドメイン配向が観察され、ディスコチックカラムナー相がランダム配向していることがわかった。
【００６３】
また、同様の手法で複素インピーダンスを測定し、イオン伝導率を算出した。その結果を以下に示す。
測定温度 イオン伝導率
５０℃ ３．６×１０^-9Ｓ／ｃｍ
【００６４】
実施例４
電解質Ａの代わりに電解質Ｂを用いる以外は実施例３と同様の手法により２種類のセルを作製、注入し、偏光顕微鏡でテクスチャーを観察した所、平均粒径２．４μｍのシリカビーズで作成したセルＡは暗視野が得られ、ディスコチックカラムナー相がホメオトロピック配向をしていることがわかった。平均粒径２０μｍのシリカビーズで作成したセルＢはマルチドメイン配向であり、ディスコチックカラムナー相がランダム配向していることがわかった。
【００６５】
実施例３と同様の手法で複素インピーダンスを測定し、イオン伝導率を算出した。その結果を以下に示す。
【００６６】
平均粒径２．４μｍシリカビーズセル
測定温度 イオン伝導率
５０℃ ９．４×１０^-8Ｓ／ｃｍ
平均粒径２０μｍシリカビーズセル
測定温度 イオン伝導率
５０℃ ８．８×１０^-9Ｓ／ｃｍ
【００６７】
比較例１
▲１▼電解質Ｃの製造
２，３，６，７，１０，１１−ヘキサ（２−ヘキシルオキシエチルオキシ）トリフェニレン６５．６ｍｇ（０．０６ｍｍｏｌ）に乾燥ジクロロメタン１ｍｌを加え、攪拌し完全に溶解させた。そこに過塩素酸リチウム０．６４ｍｇ（０．００６ｍｍｏｌ）と乾燥エタノール１ｍｌを加え２時間攪拌した。完全に溶解していることを確認した後、溶媒を留去し、減圧乾燥して電解質Ｃを得た。
【００６８】
相転移温度を以下に示す。
昇温過程
Ｃｒｙ（−３℃）Ｘ１（１９℃）Ｘ２（２７℃）Ｄｈ（８６℃）Ｉｓｏ
冷却過程
Ｉｓｏ（８４℃）Ｄｈ（７℃）Ｘ２（＜−１８℃）Ｘ１（＜−５０℃）Ｃｒｙ
Ｃｒｙ：結晶相、Ｘ１，Ｘ２：未同定の相、Ｄｈ：ディスコチックカラムナー相、Ｉｓｏ：等方相
【００６９】
▲２▼電解質Ｃのイオン伝導度の評価
電解質Ａの代わりに電解質Ｃを用いる以外は実施例３と同様の手法により２種類のセルを作製、注入し、偏光顕微鏡でテクスチャーを観察した所、２．４μｍのシリカビーズで作成したセルＡは暗視野が得られ、ディスコチックカラムナー相がホメオトロピック配向をしていることがわかったが、２０μｍのシリカビーズで作成したセルＢはマルチドメイン配向であり、ディスコチックカラムナー相がランダム配向していることがわかった。実施例３と同様の手法で複素インピーダンスを測定し、イオン伝導率を算出した。
【００７０】
その結果を以下に示す。
平均粒径２．４μｍシリカビーズセル
測定温度 イオン伝導率
５０℃ ２．４×１０^-9Ｓ／ｃｍ
平均粒径２０μｍシリカビーズセル
測定温度 イオン伝導率
５０℃ １．８×１０^-10Ｓ／ｃｍ
【００７１】
合成例２
４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ビフェニルカルボン酸４−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４’−ビフェニル（例示化合物Ｓ−１１）の製造
【００７２】
▲１▼メチルオキシトリ（エチレンオキシ）エチルオキシトシレートの製造
１００ｍｌナスフラスコにテトラエチレングリコールモノメチルエーテル２０ｇ（９６ｍｍｏｌ）とピリジン２０ｍｌを仕込み、氷浴で０℃に冷却した。ｐ−トルエンスルホン酸クロライド２３．８ｇ（１２５ｍｍｏｌ）をゆっくりと添加し、０℃で１２時間攪拌した。水を加えクロロホルムで抽出した。有機層を無水硫酸ナトリウムで乾燥後、溶媒を減圧留去し、シリカゲルクロマトグラフィー（クロロホルム／メタノール＝１００／１）で分離精製して、メチルオキシジ（エチレンオキシ）エチルオキシトシレート３４．５ｇ（９５．２ｍｍｏｌ，収率９９％）を得た。
【００７３】
▲２▼４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ビフェニルカルボン酸の製造
５００ｍｌナスフラスコに４’−ヒドロキシ−４−ビフェニルカルボン酸５ｇ（２３ｍｍｏｌ）、水酸化カリウム３．３ｇ、メタノール４００ｍｌを仕込み、１時間加熱還流を行った。メチルオキシトリ（エチレンオキシ）エチルオキシトシレート８．５ｇ（２３ｍｍｏｌ）を加え、更に２４時間加熱還流を行った。反応溶液を室温まで冷やし、１Ｎ塩酸で中和した後、水を加えクロロホルムで抽出した。有機層を無水硫酸ナトリウムで乾燥後、溶媒を減圧留去し、シリカゲルクロマトグラフィー（クロロホルム／メタノール＝３０／１）で分離精製して、白色固体４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ビフェニルカルボン酸３．８ｇ（９．４ｍｍｏｌ，収率４０％）を得た。
【００７４】
▲３▼４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ヒドロキシビフェニルの製造
５００ｍｌナスフラスコに４、４’−ビフェノール２．６ｇ（１４ｍｍｏｌ）、水酸化カリウム１．８ｇ、メタノール２５０ｍｌを仕込み、１時間加熱還流を行った。メチルオキシトリ（エチレンオキシ）エチルオキシトシレート５．１ｇ（１４ｍｍｏｌ）を加え、更に２４時間加熱還流を行った。反応溶液を室温まで冷やし、１Ｎ塩酸で中和した後、水を加えクロロホルムで抽出した。有機層を無水硫酸ナトリウムで乾燥後、溶媒を減圧留去し、シリカゲルクロマトグラフィー（クロロホルム／メタノール＝５０／１）で分離精製して、白色固体４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ヒドロキシビフェニル１．８ｇ（４．７ｍｍｏｌ，収率３３．６％）を得た。
【００７５】
▲４▼４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ビフェニルカルボン酸４−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４’−ビフェニル（例示化合物Ｓ−１１）の製造
１００ｍｌナスフラスコに４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ビフェニルカルボン酸２ｇ（５．０ｍｍｏｌ）、４‘−［メチルオキシジ（エチレンオキシ）エチルオキシ］−４−ヒドロキシビフェニル１．９ｇ（５．０ｍｍｏｌ）、１，３−ジシクロカルボジイミド０．８ｇ（１０ｍｍｏｌ）、４−ジメチルアミノピリジン０．６ｇ（５ｍｍｏｌ）、乾燥クロロホルム２０ｍｌを仕込み、２４時間室温攪拌を行った。
【００７６】
反応終了後、水を加えクロロホルムで抽出した。有機層を無水硫酸ナトリウムで乾燥後、溶媒を減圧留去し、シリカゲルクロマトグラフィー（クロロホルム／メタノール＝３０／１）で分離精製した後、再結晶（アセトン）を行い、白色固体４’−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４−ビフェニルカルボン酸４−［メチルオキシトリ（エチレンオキシ）エチルオキシ］−４‘−ビフェニル２．９ｇ（３．８ｍｍｏｌ，収率７５．２％）を得た。
【００７７】
¹Ｈ−ＮＭＲ（ＣＤＣｌ３／ＴＭＳ，σｐｐｍ）：３．４（６Ｈ，ｓ）、３．６−４．２（３２Ｈ，ｍ）、７．０（４Ｈ，ｍ）、７．３（２Ｈ，ｄ）、７．５−７．７（８Ｈ，ｍ）、８．２（２Ｈ，ｄ）
【００７８】
相転移温度を以下に示す。
昇温過程
Ｃｒｙ（５１℃）ＳｍＸ（１０４℃）ＳｍＣ（１５４℃）Ｎ（１７３℃）Ｉｓｏ
降温過程
Ｉｓｏ（１７０℃）Ｎ（１５０℃）ＳｍＣ（９９℃）ＳｍＸ（９℃）Ｃｒｙ
Ｃｒｙ：結晶相、ＳｍＸ：高次のスメクチック相、ＳｍＣ：スメクチックＣ相、Ｎ：ネマチック相、Ｉｓｏ：等方相
【００７９】
比較例２
▲１▼電解質Ｄの製造
例示化合物（Ｓ−１１）５０ｍｇ（０．０６６ｍｍｏｌ）に乾燥クロロホルム４ｍｌを加え、攪拌し完全に溶解させた。それにトリフルオロメタンスルホン酸リチウム４．０９ｍｇ（０．０２６ｍｍｏｌ）を溶解したＴＨＦ溶液１ｍｌを加え２時間攪拌した。溶媒をゆっくりと減圧留去した後、減圧乾燥し、電解質Ｄを得た。
【００８０】
相転移温度を以下に示す。
昇温過程
ＳｍＸ（９４℃）ＳｍＣ（１５１℃）ＳｍＡ（１６５℃）Ｎ（１７１℃）Ｉｓｏ
降温過程
Ｉｓｏ（１６９℃）Ｎ（１６４℃）ＳｍＡ（１５１℃）ＳｍＣ（８９℃）ＳｍＸ
ＳｍＸ：高次のスメクチック相、ＳｍＡ：スメクチックＡ相、ＳｍＣ：スメクチックＣ相、Ｎ：ネマチック相、Ｉｓｏ：等方相
【００８１】
▲２▼電解質Ｄのイオン伝導度の評価
２枚のガラス板を用意し、１枚のガラス板上に金膜を４００Åの厚さに形成し、図２に示すパターンにエッチングを行った。それぞれのガラス板上にポリイミド樹脂前駆体［東レ（株）製ＳＰ−７１０］１．５％ジメチルアセトアミド溶液を回転数２０００ｒ．ｐ．ｍ．のスピナーで１５秒間塗布した。成膜後、６０分間、３００℃加熱縮合焼成処理を施した。この時の塗膜の膜厚は約２５０Åであった。この焼成後の被膜にはアセテート植毛布によるラビング処理がなされ、その後、イソプロピルアルコール液で洗浄し、平均粒径２．０μｍのシリカビーズを一方のガラス板上に散布した後、それぞれのラビング処理軸が互いに平行となるようにし、接着シール剤［三井東圧（株）ストラクトボンド］を用いてガラス板を張り合わせ、６０分間、１７０℃にて加熱乾燥しセルＣを作成した。
【００８２】
このセルＣに電解質Ｄを等方性液体状態で注入し、等方相から３℃／ｍｉｎでスメクチックＡ相を示す温度まで冷却した。このセルを偏光顕微鏡でクロスニコル下、テクスチャーを観察した所、スメクチックＡ相のホモジニアス均一配向が観測された。次に０．００１〜１００ｋＨｚ、３０００ｍＶの交流電圧を印加した時の電流を測定して複素インピーダンスを測定し、イオン伝導率を算出した。その結果を以下に示す。
【００８３】
Ｘ方向
測定温度 イオン伝導率
４０℃ ５．２×１０^-7Ｓ／ｃｍ
８０℃ ２．０×１０^-6Ｓ／ｃｍ
Ｙ方向
測定温度 イオン伝導率
４０℃ ３．２×１０^-5Ｓ／ｃｍ
８０℃ １．２×１０^-4Ｓ／ｃｍ
【００８４】
比較例３
▲１▼電解質Ｅの製造
ポリエチレンオキシド（重量平均分子量４００）５．０ｍｇ、トリフルオロメタンスルホン酸リチウム０．８８ｍｇ（０．０５６ｍｍｏｌ）と乾燥ＴＨＦ１ｍｌを加え２時間攪拌した。完全に溶解していることを確認した後、溶媒を留去し、減圧乾燥して電解質Ｅを得た。
【００８５】
▲２▼電解質Ｅのイオン伝導度の評価
比較例２と同様の方法によりセルＣを作成し、電解質Ｄの代わりに電解質Ｅを用いる以外は比較例２と同様の方法により注入しイオン伝導率を算出した。その結果を以下に示す。
【００８６】
Ｘ方向
測定温度 イオン伝導率
４０℃ ６．９×１０^-4Ｓ／ｃｍ
８０℃ ３．２×１０^-3Ｓ／ｃｍ
Ｙ方向
測定温度 イオン伝導率
４０℃ ７．０×１０^-4Ｓ／ｃｍ
８０℃ ３．４×１０^-3Ｓ／ｃｍ
【００８７】
実施例５
▲１▼電解質Ｆの製造
合成した例示化合物（Ｓ−１１）３７．０ｍｇ（０．０５ｍｍｏｌ）に乾燥ジクロロメタン１ｍｌを加え、攪拌し完全に溶解させた。それにポリエチレンオキシド（重量平均分子量４００）３．４ｍｇ、トリフルオロメタンスルホン酸リチウム３．６ｍｇ（０．０２３ｍｍｏｌ）と乾燥ＴＨＦ１ｍｌを加え２時間攪拌した。完全に溶解していることを確認した後、溶媒を留去し、減圧乾燥して電解質Ｆを得た。
【００８８】
得られた電解質Ｆの相転移温度を示す。
昇温過程
ＳｍＸ（８０℃）ＳｍＣ（１１０℃）ＳｍＡ（１３２℃）Ｎ（１４６℃）Ｉｓｏ
降温過程
Ｉｓｏ（１４５℃）Ｎ（１３５℃）ＳｍＡ（１１６℃）ＳｍＣ（９０℃）ＳｍＸ
ＳｍＸ：高次のスメクチック相、ＳｍＡ：スメクチックＡ相、ＳｍＣ：スメクチックＣ相、Ｎ：ネマチック相、Ｉｓｏ：等方相
【００８９】
▲２▼電解質Ｆのイオン伝導度の評価
比較例２と同様の方法によりセルＣを作成し、電解質Ｄの代わりに電解質Ｆを用いる以外は比較例２と同様の方法により注入しイオン伝導率を算出した。その結果を以下に示す。
【００９０】
Ｘ方向
測定温度 イオン伝導率
４０℃ ６．９×１０^-6Ｓ／ｃｍ
８０℃ ５．３×１０^-5Ｓ／ｃｍ
Ｙ方向
測定温度 イオン伝導率
４０℃ ８．５×１０^-4Ｓ／ｃｍ
８０℃ １．０×１０^-3Ｓ／ｃｍ
【００９１】
実施例６
▲１▼電解質Ｇの製造
合成した例示化合物（Ｓ−１１）３７．０ｍｇ（０．０５ｍｍｏｌ）に乾燥ジクロロメタン１ｍｌを加え、攪拌し完全に溶解させた。それにポリエチレンオキシド（重量平均分子量４００）１０．２ｍｇ、トリフルオロメタンスルホン酸リチウム４．８ｍｇ（０．０３１ｍｍｏｌ）と乾燥ＴＨＦ２ｍｌを加え２時間攪拌した。完全に溶解していることを確認した後、溶媒を留去し、減圧乾燥して電解質Ｇを得た。
【００９２】
得られた電解質Ｇの相転移温度を示す。
昇温過程
Ｘ３（９０℃）Ｎ（１２４℃）Ｉｓｏ
降温過程
Ｉｓｏ（１２０℃）Ｎ（８７℃）Ｘ３
Ｘ３：未同定の高次の相、Ｎ：ネマチック相、Ｉｓｏ：等方相
【００９３】
▲２▼電解質Ｇのイオン伝導度の評価
比較例２と同様の方法によりセルＣを作成し、電解質Ｄの代わりに電解質Ｇを用いる以外は比較例２と同様の方法により注入しイオン伝導率を算出した。その結果を以下に示す。
【００９４】
Ｘ方向
測定温度 イオン伝導率
４０℃ ８．９×１０^-6Ｓ／ｃｍ
８０℃ ８．０×１０^-5Ｓ／ｃｍ
Ｙ方向
測定温度 イオン伝導率
４０℃ ７．７×１０^-3Ｓ／ｃｍ
８０℃ ３．０×１０^-3Ｓ／ｃｍ
【００９５】
【発明の効果】
以上説明した様に、本発明によれば、電池、センサデバイス等エレクトロニクス分野に用いる電解質においてイオン伝導性に異方性がある電解質を提供する事が出来る。
【図面の簡単な説明】
【図１】二次電池の模式的な構成図である。
【図２】セルＣのパターン図である。
【符号の説明】
４１ 負電極
４１１ 電子伝導性支持体
４１２ 負極活物質
４２ 正電極
４２１ 電子伝導性支持体
４２２ 正極活物質
４３ 電解質層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a novel electrolyte used in the electronics field such as a battery device, a photochromic device, and a sensor device.
[0002]
[Prior art]
In 1973, Wright et al. Reported the ion conduction characteristics of complexes of polyethylene oxide (PEO) and alkali metal salts. In 1979, Armand et al. Demonstrated the potential of electrolytes for batteries. Has spread worldwide. Since the solid electrolyte is not liquid, there is no leakage outside the unit, and it is advantageous over the liquid electrolyte in terms of heat resistance, reliability, safety, and device miniaturization. Moreover, since organic substances are more flexible than inorganic substances, there is an advantage that they are easy to process.
[0003]
In general, the ionic conductivity of an electrolyte is expressed by the product of carrier density, electric charge, and ion mobility. Therefore, a high polarity for dissociating ions and a low viscosity for moving dissociated ions are required. From this point of view, PEO cannot be said to have sufficient characteristics as a solid electrolyte. In the first place, the ion transport mechanism of PEO is based on ligand exchange in which ions dissociated by coordination to the donor polar group portion are successively delivered by segmental motion due to heat. For this reason, it is susceptible to temperature dependence. Further, when a large amount of metal ions is dissolved in order to increase the carrier density, crystallization occurs and conversely the ion mobility decreases. In order to prevent this crystallization, urethane cross-linked PEO (M. Watanabe et al, “Solid State Ionics”, 28-30, 911, 1988), and further to the cross-linked portion to improve the ion mobility at low temperature. A chain-introduced PEO ("Proceedings of the 40th Polymer Discussion", 3766, 1991) has also been developed. Recently, molten salt type PEO (K. Ito et al., “Solid State Ionics”, 86-88, 325, 1996, K. Ito et al., “Electrochim. Acta”) in which a salt is introduced at the end of the PEO is introduced. 42, 1561, 1997) have also been developed. However, since ionic conductivity cannot be obtained sufficiently at present, an electrolyte solution in which a high dielectric constant organic solvent and a low viscosity solvent are mixed or a gel electrolyte in which the electrolyte solution is fixed with an organic polymer has become the mainstream. Further, when using a solid electrolyte as a battery device, not only the ion transport efficiency but also the efficiency of the electrochemical reaction at the contact surface with the electrode is a problem.
[0004]
On the other hand, the discotic liquid crystal phase was developed in S. It is a liquid crystal phase discovered by Chandrasekhar et al. (“Pramana” 9 , 471 (1977)). For example, by the same authors, the title “Discussion Liquid Crystals” is “Rep. Prog. Phys.” 53 (1990) 57, or by Takenaka Shunsuke “The design and synthesis of discotic liquid crystal molecules”. As described in the volume “Political Chemistry” Vol. 22, p. 60, it can be seen in compounds in which a plurality of relatively long side chains are bonded to a disk-shaped core.
[0005]
The types of the compounds can be classified mainly by the structure of the core, such as 6-substituted benzene and 3-substituted benzene derivatives, phthalocyanine and porphyrin derivatives, triphenylene, torquesen, pyrylium derivatives, tribenzocyclononene derivatives, azacrown. Derivatives, cyclohexane derivatives and the like.
[0006]
Due to the structural characteristics of discotic liquid crystals, there have been some reports suggesting application to devices in the past. In systems with conjugated pi-electrons such as phthalocyanine and triphenylene, the application of electron (or hole) channels (Piechocki et al .: “J. Am. Chem. Soc.” 1982, 104, pp 5245), where the core is azacrown. In the case of such a ring, application of a molecular channel through which molecules selectively pass through a central void (“J. Chem. Soc., Chem. Commun.”, 1985, 1794, “J. Chem. Soc. Chem. Commun. ", 1995, 117, 9957).
[0007]
Recently, Kato et al. Reported on an electrolyte having a smectic liquid crystal phase (“1998 Proceedings of the Liquid Crystal Society of Japan”, 3BO8), and Japanese Patent Application Laid-Open No. 11-86629 uses the orientation of liquid crystals. An ion conductive material is disclosed. However, there is no description in which a liquid crystal compound, a linear or branched polyether compound and a metal salt are mixed and used.
[0008]
[Problems to be solved by the invention]
The present invention has been made in view of such prior art, and provides an electrolyte having anisotropy in ion conductivity, which contains a liquid crystal compound, a linear or branched polyether compound, and a metal salt. The purpose is to do.
[0009]
[Means for Solving the Problems]
That is, the present invention is an electrolyte comprising a discotic liquid crystal compound, a linear or branched polyether compound, and a metal salt.
[0010]
The present invention also provides an electrolyte comprising a liquid crystal compound that has been polymerized by a polymerization reaction, a linear or branched polyether compound, and a metal salt.
The present invention also provides an electrolyte containing an organic solvent, a liquid crystal compound, a linear or branched polyether compound, and a metal salt.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The electrolyte of the present invention includes a liquid crystal compound, a linear or branched polyether compound, and a metal salt.
[0013]
As the liquid crystal compound, a nematic liquid crystal compound typified by a rod-like liquid crystal, a smectic liquid crystal compound and a discotic liquid crystal compound are used, and a discotic liquid crystal compound having a columnar phase is preferable. These liquid crystal compounds are preferably polymerized by polymerization. In this case, a method in which a polymer group such as an acrylic group, a methacryl group, an epoxy group, or a vinyl group is added to the terminal of the liquid crystal side chain, and a method in which it is copolymerized with another polymerizable compound are preferable. Other polymerizable compounds are not particularly limited, and examples thereof include acrylic acid derivatives, methacrylic acid derivatives, vinyl derivatives, styrene derivatives, urethane derivatives, and epoxy derivatives.
[0014]
Further, the content of the liquid crystal compound contained in the electrolyte of the present invention is usually 99 to 50% by weight, preferably 95 to 70% by weight. If it is less than 50% by weight, it is difficult to maintain the liquid crystallinity, and if it exceeds 99% by weight, the ionic conductivity is lowered, which is not preferable.
[0015]
Examples of the linear or branched polyether compound include polyethylene oxide, polypropylene oxide, and copolymers thereof, and those having an average molecular weight of 200 to 6000 are preferable.
[0016]
Further, the content of the linear or branched polyether compound contained in the electrolyte of the present invention is usually 1 to 50% by weight, preferably 5 to 30% by weight. If it is less than 1% by weight, the ionic conductivity is lowered, and if it exceeds 50% by weight, it is difficult to maintain liquid crystallinity.
[0017]
Examples of the metal salt include alkali metal salts such as MClO ₄ , MBF ₄ , MPF ₆ , MCF ₃ SO ₂ , M (CF ₃ SO ₂ ) ₂ N (M represents Li, Na, K), and CuSO. ₄ , It is preferable to contain metal salts such as Ni (NO ₃ ) ₂ and Ni (BF ₄ ) ₂ . Particularly preferred are lithium metal salts such as LiClO ₄ , LiBF ₄ , LiPF ₆ , LiCF ₃ SO ₂ and Li (CF ₃ SO ₂ ) ₂ N.
[0018]
Further, the content of the metal salt contained in the electrolyte of the present invention is usually 0.01 to 50% by weight, preferably 0.1 to 30% by weight.
[0019]
The electrolyte of the present invention may contain an organic solvent, and is preferably a polar organic solvent. For example, ethylene carbonate, propylene carbonate, γ-butyrolactone, tetrahydrofuran, dioxane, ethyl ethyl ketone, methyl propionate, dimethoxy Ethane and glycols.
[0020]
In the present invention, anisotropy is imparted to ionic conduction by combining a polyether compound and a liquid crystal compound. However, not only that, many combinations can be made, and the Tg, viscosity, and ionic conduction of the electrolyte can be changed. Adjustment of electrolyte characteristics such as temperature dependency is facilitated.
[0021]
Hereinafter, specific structures of the polyether compound used in the present invention are preferably those represented by the following general formulas (a) to (d). However, the present invention is not limited to these.
[0022]
[Chemical 1]

[0023]
In the formula, n is an integer of 5 to 100, preferably 5 to 50. m is an integer of 1 to 50, preferably 1 to 10. x shows 0.1-0.9.
[0024]
Next, the liquid crystal compound used in the present invention is preferably a compound represented by the following general formulas (I) to (II).
[0025]
[Chemical formula 2]

[0026]
In the general formula (I), R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each independently composed of two or more OCH ₂ CH ₂ segments or OCH ₂ CH ₂ CH ₂ segments, A side chain having a branched or straight chain alkyl group having 1 to 20 carbon atoms in the portion is shown. However, a hydrogen atom in the alkyl group may be replaced with a fluorine atom, and one or more methylene groups may be replaced with O, CO, —CH═CH—, —C≡C— or an epoxy group. Good.
[0027]
In the general formula (I), preferably R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each independently (OCH ₂ CH ₂ ) _n OR ₇ or (OCH ₂ CH ₂ CH ₂ ) _n. OR ₇ In the formula, n is an integer of 1 to 20, and R ₇ represents a branched or straight chain alkyl group having 4 to 20 carbon atoms. The hydrogen atom in the alkyl group may be replaced with a fluorine atom, and one or more methylenes may be replaced with O, CO, —CH═CH—, —C≡C— or an epoxy group.
[0028]
[Chemical 3]

[0029]
In the general formula (II), A represents A1-B1-A2-B2-A3-B3-A4-B4-A5-B5-A6.
A1, A2 and A3 represent 1,4-phenylene (one or more CH may be replaced by CF or N) or 1,4-cyclohexylene.
A4, A5 and A6 each represents a single bond or 1,4-phenylene (one or more CH may be replaced by CF or N) or 1,4-cyclohexylene.
B1, B2, B3, B4, and B5 each represents a single bond or —CH ₂ O—, —OCH ₂ —, —COO—, —OOC—.
X represents —CH ₂ CH ₂ O— or —CHCH ₃ CH ₂ O—.
Y represents —OCH ₂ CH ₂ — or —OCH ₂ CHCH ₃ —.
R ₁₁ and R ₁₂ are each independently a linear or branched alkyl group having 1 to 100 carbon atoms, and one or more methylenes in the alkyl group are —O—, —CO—, — S—, —CH═CH—, —C≡C— may be substituted. The hydrogen atom in the alkyl group may be replaced with a fluorine atom.
m1 and n1 represent integers from 3 to 25. An optically active compound may be used.
[0030]
Further, preferably, in the general formula (II), the compound A is a compound represented by the following general formulas (IIa) to (IIi).
In formula, z shows the integer of 0-4 each independently.
[0031]
[Formula 4]

[0032]
[Chemical formula 5]

Hereinafter, specific structural formulas of the liquid crystal compounds used in the electrolyte of the present invention are shown in Tables 1 to 14. However, the present invention is not limited to these. In addition, the abbreviation in a table | surface shows the following groups.
[0033]
[Chemical 6]

[0034]
[Chemical 7]

[0035]
[Table 1]

[0036]
[Table 2]

[0037]
[Table 3]

[0038]
[Table 4]

[0039]
[Table 5]

[0040]
[Table 6]

[0041]
[Table 7]

[0042]
[Table 8]

[0043]
[Table 9]

[0044]
[Table 10]

[0045]
[Table 11]

[0046]
[Table 12]

[0047]
[Table 13]

[0048]
[Table 14]

[0049]
Next, a secondary battery will be described as an application example of the electrolyte of the present invention.
FIG. 1 is a schematic configuration example of a secondary battery. Reference numerals 41 and 42 denote negative and positive electrodes, respectively. 43 is an electrolyte layer, and ions of a specific polarity are transmitted from the negative electrode to the positive electrode or from the positive electrode to the negative electrode through the layer as a passage. The negative and positive electrodes are normally separated because they require functions that are ambiguous, such as ion emission and absorption functions, linkage functions with external devices (for example, electronic conductivity functions), and mechanical support functions. In many cases, the composite is composed of a plurality of members.
[0050]
The negative electrode 41 is formed by coating a negative electrode active material 412 on an electronically conductive support 411 such as copper, aluminum, gold, or platinum that also serves as an electronic connection with an external circuit. Alternatively, a negative electrode active material that also functions as a support can be used. As a negative electrode active material, a lithium metal foil, lithium-aluminum from a metal material as a material capable of releasing cations such as alkali ions such as Li ions, Na ions and K ions, alkaline earth ions and hydrogen ions. Alloys such as polyacetylene, polythiophene, poly-p-phenylene, polyacene and their derivatives doped with n-type from among polymer materials, and derivatives thereof, and graphite (graphite), pitch, coke, A sintered body of an organic polymer or a composite of these materials and an organic polymer is selectively used as appropriate.
[0051]
The positive electrode 42 is formed by coating a positive electrode active material 422 on an electronically conductive support 421 such as copper, aluminum, gold, or platinum that also functions as an electronic connection with an external circuit. Alternatively, a positive electrode active material that also serves as a support can be used. As the positive electrode active material, transition metal chalcogen compounds and oxides such as cobalt, vanadium, titanium, molybdenum, iron, and manganese, as well as composites of these with lithium, are composed of graphite, fluoride, and carbon. Polyacetylene, polyaniline, polypyrrole, polythiophene, poly-p-phenylene in which a series of layered compounds such as carbonized carbon, or a composite of these materials and an organic polymer is preferably doped into p-type or n-type among polymer materials , Polyacene, polyphthalocyanine, polypyridine and the like, and derivatives thereof are selectively used as appropriate.
[0052]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.
[0053]
Synthesis example 1
Production of 2,3,6,7,10,11-hexa (2-hexyloxyethyloxy) triphenylene (Exemplary Compound T-6) (1) Production of 2-hexyloxyethyl p-toluenesulfonate -Add 3.29 g (22.5 mmol) of hexyloxyethanol and 5.33 g (67.5 mmol) of pyridine, add 4.72 g (24.7 mmol) of p-toluenesulfonic acid chloride to the ice bath, and stir for 1 hour Then, the mixture was further stirred at room temperature for 3 hours. After completion of the reaction, the mixture was acidified with 3N HCl, and extracted twice with toluene. The extract was washed with water, dried over anhydrous sodium sulfate. After the solvent was distilled off, the residue was purified by silica gel column chromatography (eluent: toluene / ethyl acetate = 10/1) to obtain 6.45 g (21.5 mmol) of 2-hexyloxyethyl p-toluenesulfonate. Yield 95%
[0054]
(2) Production of 2,3,6,7,10,11-hexa (2-hexyloxyethyloxy) triphenylene In a reaction vessel, 15 ml of dry N, N-dimethylformamide (DMF) and sodium hydride (60% in oil) (Mineral oil)) 0.77 g (19.3 mmol) was added, 0.93 g (2.84 mmol) of 2,3,6,7,10,11-hexahydroxytriphenylene was added to the solution in a water bath, and the mixture was stirred for 1 hour. Thereafter, a mixed solution of 6.3 g (21.0 mmol) of 2-hexyloxyethyl p-toluenesulfonate and 5 ml of dry DMF was added dropwise, and the mixture was stirred at 80 ° C. for 5 hours. After completion of the reaction, water was added and extracted twice with toluene. The extract was washed with water, dried over anhydrous sodium sulfate. After the solvent was distilled off, silica gel column chromatography (eluent: toluene / ethyl acetate = 5/1) was performed twice for purification, and 2,3,6,7,10,11-hexa (2-hexyloxyethyl). 1.15 g (1.0 mmol) of oxy) triphenylene was obtained. Yield 35%
[0055]
The phase transition temperature by DSC of the obtained compound is shown below.
Temperature rise process Cry (-24 ° C) Xl (17 ° C) X2 (29 ° C) Dh (84 ° C) Iso
Cooling process Iso (81 ° C) Dh (16 ° C) X2 (5 ° C) Xl (<-50 ° C) Cry
Cry: crystalline phase, X1, X2: unidentified phase, Dh: discotic columnar phase, Iso: isotropic phase
Example 1
Next, 1 ml of dry dichloromethane was added to 65.6 mg (0.06 mmol) of 2,3,6,7,10,11-hexa (2-hexyloxyethyloxy) triphenylene synthesized, and the mixture was stirred and completely dissolved. To this, 2.4 mg of polyethylene oxide (weight average molecular weight 400), 3.19 mg (0.030 mmol) of lithium perchlorate and 1 ml of dry ethanol were added and stirred for 2 hours. After confirming complete dissolution, the solvent was distilled off and dried under reduced pressure to obtain an electrolyte A.
[0057]
The phase transition temperature of the obtained electrolyte A is shown.
Temperature rise process Cry (<-50 ° C) Xl (22 ° C) X2 (29 ° C) Dh (88 ° C) Iso
Cooling Process Iso (86 ° C) Dh (10 ° C) X2 (<-50 ° C) Xl (<-50 ° C) Cry
Cry: crystalline phase, X1, X2: unidentified phase, Dh: discotic columnar phase, Iso: isotropic phase
Example 2
To 65.6 mg (0.06 mmol) of 2,3,6,7,10,11-hexa (2-hexyloxyethyloxy) triphenylene was added 1 ml of dry dichloromethane, and the mixture was stirred and completely dissolved. 4.8 mg of polyethylene oxide (weight average molecular weight 3000), 3.19 mg (0.030 mmol) of lithium perchlorate and 1 ml of dry ethanol were added thereto and stirred for 2 hours. After confirming complete dissolution, the solvent was distilled off and dried under reduced pressure to obtain an electrolyte B.
[0059]
The phase transition temperature of the obtained electrolyte B is shown.
Temperature rise process Cry (<-50 ° C) Xl (28 ° C) X2 (31 ° C) Dh (90 ° C) Iso
Cooling process Iso (88 ° C) Dh (11 ° C) X2 (<-50 ° C) Xl (<-50 ° C) Cry
Cry: crystalline phase, X1, X2: unidentified phase, Dh: discotic columnar phase, Iso: isotropic phase
Example 3
A pair of glass substrates having a thickness of 1.1 mm on which an ITO film having a thickness of 700 mm was formed as a transparent electrode was prepared. On the transparent electrode of the substrate, silica beads having an average particle diameter of 2.4 μm were dispersed as a spacer on one substrate to produce a cell A having a uniform cell gap. The electrolyte A prepared in Example 1 was injected into this cell in an isotropic liquid state, and cooled from the isotropic phase to a temperature showing a discotic columnar phase at 20 ° C./h. When this cell was observed with a polarizing microscope under a crossed Nicol texture, a dark field was obtained, and it was found that the discotic columnar phase had homeotropic orientation.
[0061]
Next, the complex impedance was measured by measuring the current when an alternating voltage of 0.001 to 100 kHz and 10 mV was applied, and the ionic conductivity was calculated. The results are shown below.
Measurement temperature Ion conductivity 50 ° C. 1.1 × 10 ⁻⁷ S / cm
[0062]
Next, instead of using silica beads with an average particle diameter of 2.4 μm, a cell B was prepared in the same manner except that silica beads with an average particle diameter of 20 μm were used, electrolyte A was injected, and the texture was observed with a polarizing microscope. As a result, multi-domain orientation was observed, and it was found that the discotic columnar phase was randomly oriented.
[0063]
Moreover, the complex impedance was measured by the same method, and the ionic conductivity was calculated. The results are shown below.
Measurement temperature Ion conductivity 50 ° C. 3.6 × 10 ⁻⁹ S / cm
[0064]
Example 4
Two types of cells were prepared and injected in the same manner as in Example 3 except that electrolyte B was used instead of electrolyte A. The texture was observed with a polarizing microscope, and the beads were prepared with silica beads having an average particle size of 2.4 μm. Cell A was found to have a dark field, and the discotic columnar phase was homeotropically oriented. It was found that the cell B made of silica beads having an average particle diameter of 20 μm was multi-domain aligned and the discotic columnar phase was randomly aligned.
[0065]
Complex impedance was measured by the same method as in Example 3, and ionic conductivity was calculated. The results are shown below.
[0066]
Average particle size 2.4 μm Silica beads cell Measurement temperature Ion conductivity 50 ° C. 9.4 × 10 ⁻⁸ S / cm
Average particle diameter 20 μm Silica beads cell Measurement temperature Ion conductivity 50 ° C. 8.8 × 10 ⁻⁹ S / cm
[0067]
Comparative Example 1
(1) Production of electrolyte C Add 1 ml of dry dichloromethane to 65.6 mg (0.06 mmol) of 2,3,6,7,10,11-hexa (2-hexyloxyethyloxy) triphenylene and stir to dissolve completely. It was. Thereto were added lithium perchlorate 0.64 mg (0.006 mmol) and dry ethanol 1 ml, and the mixture was stirred for 2 hours. After confirming complete dissolution, the solvent was distilled off and dried under reduced pressure to obtain an electrolyte C.
[0068]
The phase transition temperature is shown below.
Temperature rising process Cry (-3 ° C) X1 (19 ° C) X2 (27 ° C) Dh (86 ° C) Iso
Cooling process Iso (84 ° C.) Dh (7 ° C.) X2 (<−18 ° C.) X1 (<−50 ° C.) Cry
Cry: crystalline phase, X1, X2: unidentified phase, Dh: discotic columnar phase, Iso: isotropic phase
(2) Evaluation of ionic conductivity of electrolyte C Two types of cells were prepared and injected in the same manner as in Example 3 except that electrolyte C was used instead of electrolyte A, and the texture was observed with a polarizing microscope. Cell A made with 4 μm silica beads has a dark field, and the discotic columnar phase was found to be homeotropic, but cell B made with 20 μm silica beads is multidomain oriented. It was found that the discotic columnar phase was randomly oriented. Complex impedance was measured by the same method as in Example 3, and ionic conductivity was calculated.
[0070]
The results are shown below.
Average particle size 2.4 μm Silica beads cell Measurement temperature Ion conductivity 50 ° C. 2.4 × 10 ⁻⁹ S / cm
Average particle size 20 μm Silica beads cell Measurement temperature Ion conductivity 50 ° C. 1.8 × 10 ⁻¹⁰ S / cm
[0071]
Synthesis example 2
Production of 4 ′-[methyloxytri (ethyleneoxy) ethyloxy] -4-biphenylcarboxylic acid 4- [methyloxytri (ethyleneoxy) ethyloxy] -4′-biphenyl (Exemplary Compound S-11)
(1) Production of methyloxytri (ethyleneoxy) ethyloxytosylate 20 g (96 mmol) of tetraethylene glycol monomethyl ether and 20 ml of pyridine were charged into a 100 ml eggplant flask and cooled to 0 ° C. in an ice bath. 23.8 g (125 mmol) of p-toluenesulfonic acid chloride was slowly added and stirred at 0 ° C. for 12 hours. Water was added and extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was separated and purified by silica gel chromatography (chloroform / methanol = 100/1) to obtain 34.5 g (95.95%) of methyloxydi (ethyleneoxy) ethyloxytosylate. 2 mmol, 99% yield).
[0073]
(2) Production of 4 '-[methyloxytri (ethyleneoxy) ethyloxy] -4-biphenylcarboxylic acid In a 500 ml eggplant flask, 5 g (23 mmol) of 4'-hydroxy-4-biphenylcarboxylic acid, 3.3 g of potassium hydroxide, 400 ml of methanol was charged and heated under reflux for 1 hour. Methyloxytri (ethyleneoxy) ethyloxytosylate (8.5 g, 23 mmol) was added, and the mixture was further heated under reflux for 24 hours. The reaction solution was cooled to room temperature, neutralized with 1N hydrochloric acid, water was added, and the mixture was extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was separated and purified by silica gel chromatography (chloroform / methanol = 30/1) to give a white solid 4 ′-[methyloxytri (ethyleneoxy) ethyloxy]. 3.8 g (9.4 mmol, yield 40%) of -4-biphenylcarboxylic acid was obtained.
[0074]
(3) Production of 4 '-[methyloxytri (ethyleneoxy) ethyloxy] -4-hydroxybiphenyl In a 500 ml eggplant flask, 2.6 g (14 mmol) of 4,4'-biphenol, 1.8 g of potassium hydroxide and 250 ml of methanol were added. The mixture was heated and refluxed for 1 hour. Methyloxytri (ethyleneoxy) ethyloxytosylate (5.1 g, 14 mmol) was added, and the mixture was further heated under reflux for 24 hours. The reaction solution was cooled to room temperature, neutralized with 1N hydrochloric acid, water was added, and the mixture was extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was separated and purified by silica gel chromatography (chloroform / methanol = 50/1) to give a white solid 4 ′-[methyloxytri (ethyleneoxy) ethyloxy]. 1.8 g (4.7 mmol, yield 33.6%) of -4-hydroxybiphenyl was obtained.
[0075]
(4) Production of 4 ′-[methyloxytri (ethyleneoxy) ethyloxy] -4-biphenylcarboxylic acid 4- [methyloxytri (ethyleneoxy) ethyloxy] -4′-biphenyl (Exemplary Compound S-11) 100 ml eggplant In a flask, 2 g (5.0 mmol) of 4 ′-[methyloxytri (ethyleneoxy) ethyloxy] -4-biphenylcarboxylic acid, 1.9 g of 4 ′-[methyloxydi (ethyleneoxy) ethyloxy] -4-hydroxybiphenyl (5. 0 mmol), 0.8 g (10 mmol) of 1,3-dicyclocarbodiimide, 0.6 g (5 mmol) of 4-dimethylaminopyridine, and 20 ml of dry chloroform were stirred at room temperature for 24 hours.
[0076]
After completion of the reaction, water was added and extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, the residue was separated and purified by silica gel chromatography (chloroform / methanol = 30/1), recrystallized (acetone), and white solid 4 ′-[methyl Oxytri (ethyleneoxy) ethyloxy] -4-biphenylcarboxylic acid 4- [methyloxytri (ethyleneoxy) ethyloxy] -4'-biphenyl 2.9 g (3.8 mmol, yield 75.2%) was obtained.
[0077]
¹ H-NMR (CDCl 3 / TMS, σ ppm): 3.4 (6H, s), 3.6-4.2 (32H, m), 7.0 (4H, m), 7.3 (2H, d ), 7.5-7.7 (8H, m), 8.2 (2H, d)
[0078]
The phase transition temperature is shown below.
Temperature rising process Cry (51 ° C.) SmX (104 ° C.) SmC (154 ° C.) N (173 ° C.) Iso
Temperature reduction process Iso (170 ° C.) N (150 ° C.) SmC (99 ° C.) SmX (9 ° C.) Cry
Cry: crystalline phase, SmX: higher smectic phase, SmC: smectic C phase, N: nematic phase, Iso: isotropic phase
Comparative Example 2
(1) Production of electrolyte D 4 ml of dry chloroform was added to 50 mg (0.066 mmol) of the exemplified compound (S-11), and the mixture was stirred and completely dissolved. 1 ml of a THF solution in which 4.09 mg (0.026 mmol) of lithium trifluoromethanesulfonate was dissolved was added thereto and stirred for 2 hours. The solvent was slowly distilled off under reduced pressure and then dried under reduced pressure to obtain an electrolyte D.
[0080]
The phase transition temperature is shown below.
Temperature raising process SmX (94 ° C.) SmC (151 ° C.) SmA (165 ° C.) N (171 ° C.) Iso
Temperature drop process Iso (169 ° C.) N (164 ° C.) SmA (151 ° C.) SmC (89 ° C.) SmX
SmX: Higher order smectic phase, SmA: Smectic A phase, SmC: Smectic C phase, N: Nematic phase, Iso: Isotropic phase
{Circle around (2)} Evaluation of Ion Conductivity of Electrolyte D Two glass plates were prepared, a gold film was formed to a thickness of 400 mm on one glass plate, and the pattern shown in FIG. 2 was etched. A polyimide resin precursor [SP-710 manufactured by Toray Industries, Inc.] 1.5% dimethylacetamide solution was added to each glass plate at a rotational speed of 2000 r. p. m. For 15 seconds. After film formation, a heat condensation baking process at 300 ° C. was performed for 60 minutes. At this time, the thickness of the coating film was about 250 mm. The baked coating is rubbed with an acetate blanket, then washed with isopropyl alcohol solution, and silica beads having an average particle size of 2.0 μm are dispersed on one glass plate, and then each rubbed shaft is rubbed. Were made parallel to each other, and a glass plate was laminated using an adhesive sealant [Strong Bond, Mitsui Toatsu Co., Ltd.], and heat-dried at 170 ° C. for 60 minutes to prepare cell C.
[0082]
Electrolyte D was injected into cell C in an isotropic liquid state, and cooled from the isotropic phase to a temperature showing a smectic A phase at 3 ° C./min. When the texture of this cell was observed with a polarizing microscope under crossed Nicols, homogeneous uniform orientation of the smectic A phase was observed. Next, the complex impedance was measured by measuring the current when an alternating voltage of 0.001 to 100 kHz and 3000 mV was applied, and the ionic conductivity was calculated. The results are shown below.
[0083]
X direction measurement temperature Ion conductivity 40 ° C 5.2 × 10 ^-7 S / cm
80 ° C. 2.0 × 10 ⁻⁶ S / cm
Y direction measurement temperature Ion conductivity 40 ° C 3.2 × 10 ^-5 S / cm
80 ° C. 1.2 × 10 ⁻⁴ S / cm
[0084]
Comparative Example 3
(1) Production of electrolyte E 5.0 mg of polyethylene oxide (weight average molecular weight 400), 0.88 mg (0.056 mmol) of lithium trifluoromethanesulfonate and 1 ml of dry THF were added and stirred for 2 hours. After confirming complete dissolution, the solvent was distilled off and dried under reduced pressure to obtain an electrolyte E.
[0085]
(2) Evaluation of ion conductivity of electrolyte E Cell C was prepared by the same method as in Comparative Example 2, and ion conductivity was injected by the same method as in Comparative Example 2 except that electrolyte E was used instead of electrolyte D. Calculated. The results are shown below.
[0086]
X direction measurement temperature Ion conductivity 40 ° C. 6.9 × 10 ⁻⁴ S / cm
80 ° C. 3.2 × 10 ⁻³ S / cm
Y direction measurement temperature Ionic conductivity 40 ° C. 7.0 × 10 ⁻⁴ S / cm
80 ° C. 3.4 × 10 ⁻³ S / cm
[0087]
Example 5
(1) Production of Electrolyte F 1 ml of dry dichloromethane was added to 37.0 mg (0.05 mmol) of the synthesized exemplary compound (S-11), and the mixture was stirred and completely dissolved. To this, 3.4 mg of polyethylene oxide (weight average molecular weight 400), 3.6 mg (0.023 mmol) of lithium trifluoromethanesulfonate and 1 ml of dry THF were added and stirred for 2 hours. After confirming complete dissolution, the solvent was distilled off and dried under reduced pressure to obtain an electrolyte F.
[0088]
The phase transition temperature of the obtained electrolyte F is shown.
Temperature raising process SmX (80 ° C.) SmC (110 ° C.) SmA (132 ° C.) N (146 ° C.) Iso
Temperature drop process Iso (145 ° C.) N (135 ° C.) SmA (116 ° C.) SmC (90 ° C.) SmX
SmX: Higher smectic phase, SmA: Smectic A phase, SmC: Smectic C phase, N: Nematic phase, Iso: Isotropic phase
(2) Evaluation of ion conductivity of electrolyte F Cell C was prepared by the same method as in Comparative Example 2, and ion conductivity was injected by the same method as in Comparative Example 2 except that electrolyte F was used instead of electrolyte D. Calculated. The results are shown below.
[0090]
X direction measurement temperature Ion conductivity 40 ° C. 6.9 × 10 ⁻⁶ S / cm
80 ° C. 5.3 × 10 ⁻⁵ S / cm
Y direction measurement temperature Ionic conductivity 40 ° C. 8.5 × 10 ⁻⁴ S / cm
80 ° C. 1.0 × 10 ⁻³ S / cm
[0091]
Example 6
(1) Production of Electrolyte G 1 ml of dry dichloromethane was added to 37.0 mg (0.05 mmol) of the exemplified compound (S-11) synthesized, and the mixture was stirred and completely dissolved. Thereto were added 10.2 mg of polyethylene oxide (weight average molecular weight 400), 4.8 mg (0.031 mmol) of lithium trifluoromethanesulfonate and 2 ml of dry THF, and the mixture was stirred for 2 hours. After confirming complete dissolution, the solvent was distilled off and dried under reduced pressure to obtain an electrolyte G.
[0092]
The phase transition temperature of the obtained electrolyte G is shown.
Temperature rise process X3 (90 ° C) N (124 ° C) Iso
Temperature drop process Iso (120 ° C) N (87 ° C) X3
X3: Unidentified higher order phase, N: Nematic phase, Iso: Isotropic phase
(2) Evaluation of ion conductivity of electrolyte G A cell C was prepared in the same manner as in Comparative Example 2, and the ion conductivity was measured by injecting in the same manner as in Comparative Example 2 except that the electrolyte G was used instead of the electrolyte D. Calculated. The results are shown below.
[0094]
X direction measurement temperature Ion conductivity 40 ° C. 8.9 × 10 ⁻⁶ S / cm
80 ° C. 8.0 × 10 ⁻⁵ S / cm
Y direction measurement temperature Ion conductivity 40 ° C. 7.7 × 10 ⁻³ S / cm
80 ° C. 3.0 × 10 ⁻³ S / cm
[0095]
【The invention's effect】
As described above, according to the present invention, an electrolyte having anisotropy in ion conductivity can be provided in an electrolyte used in the electronics field such as a battery and a sensor device.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a secondary battery.
FIG. 2 is a pattern diagram of a cell C. FIG.
[Explanation of symbols]
41 Negative Electrode 411 Electron Conductive Support 412 Negative Electrode Active Material 42 Positive Electrode 421 Electron Conductive Support 422 Positive Electrode Active Material 43 Electrolyte Layer

Claims (4)

An electrolyte comprising a discotic liquid crystal compound , a linear or branched polyether compound, and a metal salt . An electrolyte comprising a liquid crystal compound that has been polymerized by a polymerization reaction , a linear or branched polyether compound, and a metal salt . An electrolyte comprising an organic solvent , a liquid crystal compound, a linear or branched polyether compound, and a metal salt . The electrolyte according to any one of claims 1 to 3, wherein the liquid crystal compound is a compound represented by the following general formula (I).

(Wherein R ₁ , R ₂ , R _Three , R _Four , R _Five , R ₆ Each independently has one or more OCH ₂ CH ₂ Segment or OCH ₂ CH ₂ CH ₂ A side chain composed of segments and having a branched or straight chain alkyl group having 1 to 20 carbon atoms in the terminal portion is shown. )

Images