WO2008059990A1 - Capacitor - Google Patents

Capacitor Download PDF

Info

Publication number
WO2008059990A1
WO2008059990A1 PCT/JP2007/072597 JP2007072597W WO2008059990A1 WO 2008059990 A1 WO2008059990 A1 WO 2008059990A1 JP 2007072597 W JP2007072597 W JP 2007072597W WO 2008059990 A1 WO2008059990 A1 WO 2008059990A1
Authority
WO
WIPO (PCT)
Prior art keywords
capacitor
graphite
solvent
positive electrode
ethylene carbonate
Prior art date
Application number
PCT/JP2007/072597
Other languages
French (fr)
Japanese (ja)
Inventor
Masaki Yoshio
Hongyu Wang
Original Assignee
Im & T Ltd.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Im & T Ltd. filed Critical Im & T Ltd.
Priority to JP2008544222A priority Critical patent/JPWO2008059990A1/en
Publication of WO2008059990A1 publication Critical patent/WO2008059990A1/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/04—Hybrid capacitors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22—Electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/54—Electrolytes
    • H01G11/58—Liquid electrolytes
    • H01G11/60—Liquid electrolytes characterised by the solvent
    • 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
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries

Definitions

  • the present invention relates to a capacitor having a large capacitance, and more particularly to an electric double layer capacitor capable of operating at a high voltage.
  • Capacitors are electrical elements mainly composed of a positive electrode, a negative electrode, and a lithium-based non-aqueous electrolyte. Capacitors with various configurations have been proposed so far, and power sources such as mopile equipment, power storage systems for regeneration, personal computers, etc. It has been put to practical use as a backup power source.
  • the activated carbon used in such an electric double layer capacitor is activated using so-called water vapor or caustic potash (KOH) to increase the surface area, and the surface area is 1 0 0 0-3 0 0 O m 2 I have also reached ⁇ . For this reason, increasing the voltage has the disadvantage that the electrolyte solution decomposes and the life is shortened. As a result, the charging voltage has been limited to 2.3 V in the past and 2.5 V in recent years, with a few manufacturers having 2.7 V.
  • electric double layer capacitors using a graphite material as an electrode have been developed (in particular, Patent Document 1 uses a graphite material for the positive electrode and activated carbon or a non-porous carbonaceous material for the negative electrode. The electric double layer capacitor has also been described) Force S, which is superior in capacitance and withstand voltage compared to a capacitor using conventional activated carbon as an electrode (see, for example, Patent Documents 1 to 4).
  • Patent Document 1 Japanese Patent Laid-Open No. 2005-294780
  • Patent Document 2 Japanese Patent Laid-Open No. 2002-25867
  • Patent Document 3 Japanese Patent Laid-Open No. 2002-1 51 364
  • Patent Document 4 JP-A-2006-2951 53
  • a solvent mainly composed of a mixed solvent of ethylene carbonate (EC) and propylene carbonate (PC) is also known as a solvent for a capacitor electrolyte (Patent Document 5). See ⁇ 7) Force It has not been shown to combine such a solvent with an electrode containing a graphitic material.
  • Patent Document 5 JP-A-11-121285
  • Patent Document 6 Japanese Unexamined Patent Publication No. 2000-208372
  • Patent Document 7 Japanese Unexamined Patent Application Publication No. 2006-156836 Disclosure of Invention
  • An object of the present invention is to provide a capacitor having excellent withstand voltage and durability by using graphite, which hardly causes intercalation, as a positive electrode. Means for solving the problem
  • the present inventors have found that a positive electrode containing a specific graphite material, a negative electrode containing a non-graphitic carbon material such as activated carbon, and a specific non-material.
  • the inventors have found that a capacitor having a large capacitance and excellent withstand voltage stability can be obtained by combining a water electrolyte, and the present invention has been completed.
  • the present invention employs the following means in order to solve the above problems.
  • the non-aqueous electrolyte comprises, as a main solvent, a mixed solvent of ethylene carbonate and a carbonate other than ethylene carbonate, acetonitrile, or 0 / -butyl lactone.
  • the capacitor according to any one of (3) to (3).
  • the capacitor of the present invention uses an ethylene carbonate-based electrolyte solvent, a high charging voltage is possible and the capacitor has an excellent capacitance.
  • the intercalation of the electrolyte anion to the black lead-based cathode material is suppressed, the crystal lattice is hardly stretched and has excellent stability.
  • Figure 1 is an X-ray diffraction graph of positive electrode graphite associated with charging / discharging / discharging of the capacitor (sample) obtained in Comparative Example 4.
  • the capacitor of the present invention includes a positive electrode containing a specific graphite material, a negative electrode containing a non-graphitic carbon material such as activated carbon, and a specific non-aqueous electrolyte.
  • Electrolyte containing ethylene carbonate as a main solvent is particularly effective for new electric double layer capacitors with the positive electrode made of graphite.
  • the electrolyte anion does not enter the graphite material even when the voltage reaches 4 V, and high voltage charging, that is, production of a capacitor with high energy density is not possible. Therefore, it is possible to obtain a capacitor having good stability with little decomposition of the electrolyte.
  • the degree of graphitization was calculated from the (002) plane spacing (d. 2 ) of graphite using the following formula using an X-ray diffractometer.
  • the graphitization degree (%) is the above value multiplied by 100.
  • the graphite material used for the positive electrode in the present invention preferably has a graphitization degree of 90% or less, but can be used even at a graphitization degree of 100%.
  • various other materials can be used. Things can be used.
  • ethylene carbonate (EC) used as a solvent in the present invention has a melting point of room temperature. Because it is in the vicinity, it becomes solid at low temperatures and cannot be used. Therefore, it is necessary to mix with a solvent that exhibits liquid form over a wide temperature range and that is resistant to redox resistance.
  • the candidate is a carbonate ester solvent, which is preferably propylene carbonate (PC) having excellent thermal stability, or jetyl carbonate (DEC) from the viewpoint of viscosity.
  • a mixed solvent of ethylene carbonate and propylene carbonate is preferable.
  • the solvent indicates volume% unless otherwise specified), depending on the anion intercalation.
  • An increase in voltage is observed.
  • a mixing ratio of EC 5% or more is desirable.
  • the upper limit is not particularly limited, but in the case of 100% EC, when tetraethyl methyl ammonium ion (TEMABF 4 ) is used as the electrolyte salt, it is about 1.5 mol Z 1. However, it does not work as a capacitor because it consolidates.
  • TEMABF 4 tetraethyl methyl ammonium ion
  • EC 70 is desirable as the upper limit mixing ratio. If the weight of the activated carbon is increased, the capacity increases, but anion intercalation tends to occur. In this case as well, EC mixing is effective and intercalation is less likely to occur. To make negative intercalation difficult to occur, EC is preferably about 10% to 70%.
  • non-aqueous solvents include tetrahydrofuran (THF), methyltetrahydrofuran (Me THF), methylformamide, methyl acetate, dimethyl ether (DME), ⁇ -butyl lactone (GBL), dimethyl It is possible to select at least one selected from the group consisting of carbonate (DMC), acetonitrile (AN), sulfolane (SL), and these non-aqueous solvents containing a fluoride in a part of the molecule.
  • a solution obtained by dissolving a solute in the non-aqueous solvent can be used as the electrolytic solution for immersing the positive electrode and the negative electrode.
  • Anions that act in the electrolyte include tetrafluoroborate ion (BF 4 —), 6 fluhiphosphate ion (PF 6 —), perchlorate ion (C 10 4 ), arsenic hexafluoride ( A s F 6 —), antimony hexafluoride (S b F 6 —), perfluoromethylsulfonyl (CF 3 SO 2 ⁇ ), perfluoromethyl sulfonate (CF 3 SO 3 —) force
  • Cations include triethyl methyl ammonium ion (TEMA), trimethyl alkyl ammonium ion and ammonium ions having an alkyl group with 2 to 10 carbon atoms, such as symmetric and asymmetric quaternary ammonium ions.
  • Ion imidazolium derivative ions such as ethyl ion And at least one selected from the group consisting of lithium, tetraethylphosphine, and lithium ion.
  • separators, current collectors, etc. that are used for capacitors can be those usually used for capacitors.
  • the specific surface area of 1 700 meters 2 Zg steam activated carbon 2 Omg Teflon acetylene black (TAB) 5 mg of lightly were mixed in an agate mortar, molded into sheet one bets like a spatula to obtain a negative electrode.
  • Example 1 The above positive, negative electrode, separator (material: glass fiber), and propylene carbonate (PC) as a solvent, TEMAP F fi or SBPPF 6 as the solute 1-2mo 1 A capacitor with an electrolyte containing dm 3 was fabricated in a dry atmosphere, and the capacitor of Comparative Example 1 (Sample A) was obtained.
  • Example 1 The above positive, negative electrode, separator (material: glass fiber), and propylene carbonate (PC) as a solvent, TEMAP F fi or SBPPF 6 as the solute 1-2mo 1 A capacitor with an electrolyte containing dm 3 was fabricated in a dry atmosphere, and the capacitor of Comparative Example 1 (Sample A) was obtained.
  • Example 1 The above positive, negative electrode, separator (material: glass fiber), and propylene carbonate (PC) as a solvent, TEMAP F fi or SBPPF 6 as the solute 1-2mo 1 A capacitor with an electrolyte containing dm 3 was fabricated in a
  • Example 3 In the same manner as in Comparative Example 1, instead of using propylene carbonate (PC) instead of propylene carbonate (PC), a solvent with 50% propylene carbonate (PC) and 50% ethylene carbonate (EC) was used. Two capacitors (sample C) were obtained.
  • PC propylene carbonate
  • EC ethylene carbonate
  • Example 5 As the cathode material, instead of graphite with a graphitization degree of 90%, graphite for lithium ion battery cathode (Osaka Gas MCMB6-28) was used (93% graphitization degree, BET surface area 2m 2 ng). In the same manner as in Example 2, the capacitor (Sample E) of Example 4 was obtained.
  • Example 5 As the cathode material, instead of graphite with a graphitization degree of 90%, graphite for lithium ion battery cathode (Osaka Gas MCMB6-28) was used (93% graphitization degree, BET surface area 2m 2 ng). In the same manner as in Example 2, the capacitor (Sample E) of Example 4 was obtained.
  • Example 5 As the cathode material, instead of graphite with a graphitization degree of 90%, graphite for lithium ion battery cathode (Osaka Gas MCMB6-28) was used (93% graphitization degree, BET surface area 2m 2 ng). In the same manner as
  • Example 6 instead of graphite with a graphitization degree of 90% as a positive electrode material, we used lithium ion battery positive electrode (Hitachi Chemical Co., Ltd. MAG-D) (graphitization degree 98%, BET surface area 3m 2 / g) In the same manner as in Example 2, the capacitor (Sample F) of Example 5 was obtained.
  • Example 6 lithium ion battery positive electrode (Hitachi Chemical Co., Ltd. MAG-D) (graphitization degree 98%, BET surface area 3m 2 / g) In the same manner as in Example 2, the capacitor (Sample F) of Example 5 was obtained.
  • Example 6 lithium ion battery positive electrode (Hitachi Chemical Co., Ltd. MAG-D) (graphitization degree 98%, BET surface area 3m 2 / g)
  • Example 6 The positive electrode material of Example 6 was the same as Example 2 except that natural graphite (graphitization degree 100%, BET surface area lm 2 Zg) was used instead of graphite with a graphitization degree of 90% as the positive electrode material. (Sample G) was obtained. Comparative Example 2
  • Comparative Example 4 The same procedure as in Comparative Example 1 was used except that instead of graphite with a graphitization degree of 90%, a positive electrode material (Hitachi Chemical Co., Ltd. MAG-D) (graphitization degree 98%) was used as the positive electrode material. Thus, a capacitor (Sample K) of Comparative Example 3 was obtained. Comparative Example 4
  • Example L The capacitor (Sample L) of Comparative Example 4 was obtained in the same manner as Comparative Example 1 except that natural graphite (graphitization degree 100%) was used instead of graphite with a graphitization degree of 90% as the positive electrode material. It was.
  • Example 7
  • Example M A capacitor (sample M) of Example 7 was obtained in the same manner as in Comparative Example 1 except that was used.
  • Example 8
  • Example N The capacitor (Sample N) of Example 8 was obtained in the same manner as Comparative Example 1 except that 10% (EC) was used. Comparative Example 5
  • a capacitor (Sample O) of Comparative Example 5 was obtained in the same manner as Comparative Example 1 except that the weight ratio of the positive electrode to the negative electrode was set to 1: 1.3.
  • Table 1 summarizes the capacitor configurations of Examples 1 to 8 and Comparative Examples 1 to 5.
  • the capacitor of the present invention using graphite as a positive electrode and a solvent containing ethylene carbonate is a capacitor in which an intercalation reaction hardly occurs, and the charge voltage can be increased to 3 V or more. . It was also found that the intercalation and de-intercalation associated with charging / discharging would cause the graphite lattice to expand and contract very easily, thus extending the durability life.
  • the discharge capacity is 3 OmAh / g and the average voltage is 2.7 V in Example 1 where the weight ratio of the negative electrode to the positive electrode is 1, and in Comparative Example 1.
  • the energy density is 7 lWh / kg, but in Example 8 where the weight ratio of the negative electrode to the positive electrode is 2, the capacity is 5 OmAh / g, and the energy density is 1 35 WhZk g (both capacity per positive electrode weight, Energy density) is approximately twice as large.
  • the capacitor of the present invention using graphite as a positive electrode and a solvent containing ethylene carbonate is a capacitor in which an intercalation reaction is unlikely to occur, and the charge pressure can be increased to 3 V or more. As a result, the energy density can be increased. This is possible for the first time by using EC as the basic solvent of the mixed solvent.
  • the capacitor of the present invention Since the capacitor of the present invention has a large capacitance and can be rapidly charged and discharged, it is useful for a power source for a moving body such as an electric vehicle, an uninterruptible power supply, a power storage system for an electric utility, and the like. is there.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Electric Double-Layer Capacitors Or The Like (AREA)

Abstract

Disclosed is a capacitor having excellent withstand voltage characteristics and durability, wherein graphite which hardly causes intercalation is used for a positive electrode. Specifically disclosed is a capacitor comprising a positive electrode containing a graphite material, a negative electrode containing a non-graphite carbonaceous material and a nonaqueous electrolyte solution. This capacitor is characterized in that the solvent of the nonaqueous electrolyte solution contains ethylene carbonate.

Description

明細書  Specification
キャパシタ  Capacitors
技術分野  Technical field
本発明は、 静電容量が大きなキャパシタ、 とくに高電圧で動作可能な電気二重層キ ャパシタに関するものである。 背景技術  The present invention relates to a capacitor having a large capacitance, and more particularly to an electric double layer capacitor capable of operating at a high voltage. Background art
キャパシタは、 正極、 負極およびリチウム系非水電解質を主たる構成要素とする電 気素子であって、 これまでに種々の構成のキャパシタが提案され、 モパイル機器など の電源や回生用蓄電システム、 パーソナルコンピューターのバックアツプ電源などに 実用化されてきている。  Capacitors are electrical elements mainly composed of a positive electrode, a negative electrode, and a lithium-based non-aqueous electrolyte. Capacitors with various configurations have been proposed so far, and power sources such as mopile equipment, power storage systems for regeneration, personal computers, etc. It has been put to practical use as a backup power source.
現在開発市販されている非水溶媒を用いる電気二重層キャパシタは正極、 負極 両極材料に活性炭を用いているが、 非水溶媒としては、 主にプロピレンカーボネー トを用レ、、 欧米では低温特性に重点を置きァセトニトリルを用いている。  Currently developed and marketed electric double layer capacitors using non-aqueous solvents use activated carbon for both positive and negative electrode materials, but as non-aqueous solvents, mainly propylene carbonate is used, and low temperature characteristics in Europe and the United States. Acetonitrile is used with emphasis on.
このような電気二重層キャパシタに用いている活性炭は、 表面積を大きくするため、 いわゆる水蒸気や、 苛性カリ （K O H) を用いて賦活したものであり、 表面積が 1 0 0 0 - 3 0 0 O m 2 ^にも達している。 このため電圧を上げると電解液が分解し寿 命が短くなる欠点がある。 そのため充電電圧は、 以前は 2 . 3 V、 近年は 2 . 5 Vに 制限されており、 少数のメーカーでは 2 . 7 Vもある。 また、 近年、 黒鉛質材料を電極に用いた電気二重層キャパシタが開発されている (特に、 特許文献 1には、 正極に黒鉛質材料を用い、 負極に活性炭又は非多孔性炭素 質材料を用いた電気二重層キャパシタも記載されている） 力 S、 従来の活性炭を電極に 用いたキャパシタと較べ静電容量並びに耐電圧性に優れたものである （例えば、 特許 文献 1〜4参照） 。 The activated carbon used in such an electric double layer capacitor is activated using so-called water vapor or caustic potash (KOH) to increase the surface area, and the surface area is 1 0 0 0-3 0 0 O m 2 I have also reached ^. For this reason, increasing the voltage has the disadvantage that the electrolyte solution decomposes and the life is shortened. As a result, the charging voltage has been limited to 2.3 V in the past and 2.5 V in recent years, with a few manufacturers having 2.7 V. In recent years, electric double layer capacitors using a graphite material as an electrode have been developed (in particular, Patent Document 1 uses a graphite material for the positive electrode and activated carbon or a non-porous carbonaceous material for the negative electrode. The electric double layer capacitor has also been described) Force S, which is superior in capacitance and withstand voltage compared to a capacitor using conventional activated carbon as an electrode (see, for example, Patent Documents 1 to 4).
しかし、 これらの特許文献に記載された発明においては、 電極に用いた黒鉛質材料 と溶媒の関係については、 十分な検討がなされておらず、 実施例では、 溶媒として、 従来より一般的に用いられていたプロピレンカーボネ一トを用いている。 特許文献 1 ：特開 2005— 294780号公報 However, in the inventions described in these patent documents, the relationship between the graphite material used for the electrode and the solvent has not been sufficiently studied. In the examples, as the solvent, Propylene carbonate which has been generally used conventionally is used. Patent Document 1: Japanese Patent Laid-Open No. 2005-294780
特許文献 2 ：特開 2002— 25867号公報  Patent Document 2: Japanese Patent Laid-Open No. 2002-25867
特許文献 3 ：特開 2002— 1 51 364号公報  Patent Document 3: Japanese Patent Laid-Open No. 2002-1 51 364
特許文献 4 ：特開 2006— 2951 53号公報 一方、 キャパシタの電解液の溶媒として、 エチレンカーボネート （EC) とプロピ レンカーボネート （PC) の混合溶媒を主体としたものも公知である （特許文献 5〜 7参照） 力 このような溶媒を、 黒鉛質材料を含有する電極と組み合わせることは示 されていない。  Patent Document 4: JP-A-2006-2951 53 On the other hand, a solvent mainly composed of a mixed solvent of ethylene carbonate (EC) and propylene carbonate (PC) is also known as a solvent for a capacitor electrolyte (Patent Document 5). See ~ 7) Force It has not been shown to combine such a solvent with an electrode containing a graphitic material.
特許文献 5 ：特開平 1 1— 121 285号公報  Patent Document 5: JP-A-11-121285
特許文献 6 ：特開 2000— 208372号公報  Patent Document 6: Japanese Unexamined Patent Publication No. 2000-208372
特許文献 7 ：特開 2006— 1 56836号公報 発明の開示  Patent Document 7: Japanese Unexamined Patent Application Publication No. 2006-156836 Disclosure of Invention
発明が解決しょうとする課題  Problems to be solved by the invention
黒鉛質材料を電極に用いた特許文献 1〜4に記載の電気二重層キャパシタは、 上記 のとおり静電容量並びに耐電圧性に優れたものであるが、 より一層耐電圧性、 耐久性 の大きなキャパシタが求められている。  The electric double layer capacitors described in Patent Documents 1 to 4 using a graphite material as an electrode are excellent in electrostatic capacity and voltage resistance as described above, but have much higher voltage resistance and durability. There is a need for capacitors.
本発明は、 インターカレーシヨンの起こりにくい黒鉛を正極に用い、 耐電圧性、 耐 久性に優れたキャパシタを提供することを課題とする。 課題を解決するための手段  An object of the present invention is to provide a capacitor having excellent withstand voltage and durability by using graphite, which hardly causes intercalation, as a positive electrode. Means for solving the problem
本発明者らは、 上記の課題を解決すべく、 鋭意研究を重ねた結果、 特定の黒鉛質材 料を含有する正極、 活性炭等の非黒鉛質の炭素材料を含有する負極、 及び特定の非水 電解液を組み合わせることにより、 静電容量が大きく、 しかも耐電圧安定性にも優れ ているキャパシタが得られることを見出し、 本発明を完成させた。  As a result of intensive studies to solve the above problems, the present inventors have found that a positive electrode containing a specific graphite material, a negative electrode containing a non-graphitic carbon material such as activated carbon, and a specific non-material. The inventors have found that a capacitor having a large capacitance and excellent withstand voltage stability can be obtained by combining a water electrolyte, and the present invention has been completed.
本発明は、 上記の課題を解決するために、 以下の手段を採用する。  The present invention employs the following means in order to solve the above problems.
(1) 黒鉛質材料を含有する正極、 非黒鉛質の炭素質材料を含有する負極、 及び非水 電解液を備えてなるキャパシタにおいて、 前記非水電解液の溶媒が、 エチレンカーボ ネートを含有することを特徴とするキャパシタである。 (1) A positive electrode containing a graphite material, a negative electrode containing a non-graphitic carbonaceous material, and non-water A capacitor comprising an electrolytic solution, wherein the solvent of the non-aqueous electrolytic solution contains ethylene carbonate.
( 2 ) 前記黑鉛質材料が、 黒鉛化度が 9 0 %以下であることを特徴とする前記 （1 ) のキャパシタである。  (2) The capacitor according to (1), wherein the lead-containing material has a graphitization degree of 90% or less.
( 3 ) 前記非黒鉛質の炭素質材料が活性炭であることを特徴とする前記 （1 ) 又は ( 2 ) のキャパシタである。  (3) The capacitor according to (1) or (2), wherein the non-graphitic carbonaceous material is activated carbon.
( 4 ) 前記非水電解液が、 エチレンカーボネートと、 エチレンカーボネート以外の炭 酸エステル類、 ァセトニトリル又は 0/—プチルラク トン類との混合溶媒を主溶媒とす ることを特徴とする前記 （1 ) 〜 （3 ) のいずれか一項のキャパシタである。  (4) The non-aqueous electrolyte comprises, as a main solvent, a mixed solvent of ethylene carbonate and a carbonate other than ethylene carbonate, acetonitrile, or 0 / -butyl lactone. The capacitor according to any one of (3) to (3).
( 5 ) 前記非水電解液が、 エチレンカーボネートとプロピレンカーボネートとの混合 溶媒を主溶媒とすることを特徴とする前記 （4 ) のキャパシタである。 発明の効果  (5) The capacitor according to (4), wherein the non-aqueous electrolyte includes a mixed solvent of ethylene carbonate and propylene carbonate as a main solvent. The invention's effect
本発明のキャパシタは、 エチレンカーボネート系電解質溶媒を用いているため、 高 い充電電圧が可能となり、 静電容量に優れたものである。 また、 電解質ァニオンの黒 鉛質正極材料へのインターカレーシヨンが抑制されるため、 結晶格子の伸縮もほとん どなく、 安定性にも優れたものである。 図面の簡単な説明  Since the capacitor of the present invention uses an ethylene carbonate-based electrolyte solvent, a high charging voltage is possible and the capacitor has an excellent capacitance. In addition, since the intercalation of the electrolyte anion to the black lead-based cathode material is suppressed, the crystal lattice is hardly stretched and has excellent stability. Brief Description of Drawings
図 1は、 比較例 4で得られたキャパシタ （試料し） の充放電充放電に伴う正極黒鉛 の X線回折グラフである。 発明を実施するための最良の形態  Figure 1 is an X-ray diffraction graph of positive electrode graphite associated with charging / discharging / discharging of the capacitor (sample) obtained in Comparative Example 4. BEST MODE FOR CARRYING OUT THE INVENTION
本発明のキャパシタは、 特定の黒鉛質材料を含有する正極、 活性炭等の非黒鉛質の 炭素材料を含有する負極、 及び特定の非水電解液を備えたことを特徴とする。 エチレンカーボネートを主溶媒の一部とする電解液は、 特に、 正極を黒鉛とする新 型電気二重層キャパシタに有効である。  The capacitor of the present invention includes a positive electrode containing a specific graphite material, a negative electrode containing a non-graphitic carbon material such as activated carbon, and a specific non-aqueous electrolyte. Electrolyte containing ethylene carbonate as a main solvent is particularly effective for new electric double layer capacitors with the positive electrode made of graphite.
また、 プロピレンカーボネートを溶媒とする従来型電解液を用いた場合、 黒鉛材料 を正極とする新型キャパシタにおいては、 3. 5Vないし 3. 7V 付近から、 電解質 中のァニオンが黒鉛格子中にィンタ一力レートする。 このためキャパシタへの充電放 電に伴い、 黒鉛結晶格子が膨張収縮し、 次第に結晶格子が破壊され、 キャパシタのサ ィクル寿命が劣化する。 あるいは充電電圧を下げてィンタ一力レーシヨンが起こりに くくする必要がある。 その場合、 エネルギー密度を低く設定せざるを得なくなる。 一方、 エチレンカーボネートを主溶媒の一部として用いるならば、 4V に達しても 黒鉛質材料への電解質ァニオンのィンタ一力レーシヨンは認められず、 高電圧充電、 すなわち高エネルギー密度のキャパシタの製作が可能となり、 電解液の分解も少なく 安定性の良好なキャパシタとすることができる。 黒鉛化度は、 X 線回折装置を用いて、 黒鉛の （002) 面間隔 （d。。2) から、 次 式を用いて算出した。 In addition, when using a conventional electrolyte containing propylene carbonate as a solvent, In the new capacitor with a positive electrode, the anion in the electrolyte starts to enter the graphite lattice from around 3.5V to 3.7V. For this reason, as the capacitor is charged and discharged, the graphite crystal lattice expands and contracts, gradually destroying the crystal lattice and degrading the cycle life of the capacitor. Alternatively, it is necessary to reduce the charging voltage and make it difficult for the inverter to generate the power. In that case, the energy density must be set low. On the other hand, if ethylene carbonate is used as a part of the main solvent, the electrolyte anion does not enter the graphite material even when the voltage reaches 4 V, and high voltage charging, that is, production of a capacitor with high energy density is not possible. Therefore, it is possible to obtain a capacitor having good stability with little decomposition of the electrolyte. The degree of graphitization was calculated from the (002) plane spacing (d. 2 ) of graphite using the following formula using an X-ray diffractometer.
黒鉛化晶化度 = (3. 440-d 002) /0. 0868 Graphitization crystallinity = (3. 440-d 002 ) / 0. 0868
なお （d。。2) の値はオングス トローム単位である。 また黒鉛化度 （％) は上記値 に 100を掛けたものである。 本発明において正極に用いる黒鉛質材料は、 黒鉛化度が 90 %以下のものが好まし いが、 黒鉛化度が 100%でも使用可能で、 例えば、 特許文献 1に開示の黒鉛のほか 種々のものを用いることができる。 Note that the value of (d. 2 ) is in angstrom units. The graphitization degree (%) is the above value multiplied by 100. The graphite material used for the positive electrode in the present invention preferably has a graphitization degree of 90% or less, but can be used even at a graphitization degree of 100%. For example, in addition to the graphite disclosed in Patent Document 1, various other materials can be used. Things can be used.
後述する実施例からも明らかなように、 従来のプロピレンカーボネート （PC) を 用いる場合は、 黒鉛化度が高くなると、 特に 90— 95%以上の黒鉛では、 低い電圧 から陰イオンのインターカレーシヨン反応が起こるので、 耐電圧性、 耐久性に劣つ T いる。 これに対して、 エチレンカーボネートを主溶媒の一部として用いると、 黒鉛化 度が高くなっても、 高い電圧まで陰イオンのインター力レーシヨン反応が起こらない ので、 耐電圧性、 耐久性に優れたものになる。  As is clear from the examples described later, when conventional propylene carbonate (PC) is used, when the degree of graphitization increases, especially in the case of 90-95% or more of graphite, an anion intercalation reaction occurs from a low voltage. As a result, the voltage resistance and durability are inferior. On the other hand, when ethylene carbonate is used as a part of the main solvent, even if the degree of graphitization increases, an anion interaction reaction of anions does not occur up to a high voltage, so it has excellent withstand voltage and durability. Become a thing.
また、 負極に用いる非黒鉛質の炭素質材料としては、 通常用いられている活性炭、 非多孔性炭素質材料を用レ、ることができる。 次に、 本発明において溶媒に用いるエチレンカーボネート （EC) は、 融点を室温 付近に有するため、 低温では固体状となり使用できない。 そこで幅広い温度範囲で液 体状を示し、 かつ耐酸化還元性に耐える溶媒との混合が必要である。 その候補として は、 炭酸エステル系の溶媒で、 熱安定性に優れたプロピレンカーボネート （PC) や、 粘度の点からジェチルカーボネート （DEC) などが好ましい。 Also, as the non-graphitic carbonaceous material used for the negative electrode, commonly used activated carbon and nonporous carbonaceous material can be used. Next, ethylene carbonate (EC) used as a solvent in the present invention has a melting point of room temperature. Because it is in the vicinity, it becomes solid at low temperatures and cannot be used. Therefore, it is necessary to mix with a solvent that exhibits liquid form over a wide temperature range and that is resistant to redox resistance. The candidate is a carbonate ester solvent, which is preferably propylene carbonate (PC) having excellent thermal stability, or jetyl carbonate (DEC) from the viewpoint of viscosity.
特に、 エチレンカーボネートとプロピレンカーボネートとの混合溶媒は好ましく、 例えば、 £〇 5体積％ (以下、 特に断らない限り溶媒は体積％を示す。 ） 程度の混合 溶媒浴で、 陰イオンのインターカレーシヨンによる電圧の上昇が認められる。 した力 S つて、 EC 5%以上の混合割合が望ましい。 上限には特に制限はないが、 EC 100 %の場合、 電解質塩にトリェチルメチルアンモニゥムイオン （TEMA) の 4フッ化 物 （TEMABF4) を用いると、 1. 5モル Z 1程度であっても、 固結するので、 キャパシタとして働かない。 固結しない場合でも低温特性が悪くなるので、 EC 70 一 80%程度が上限の混合割合として、 望ましい。 また活性炭の重量を多くすると、 容量が大きくなるが、 陰イオンのインターカレーシヨンが起こりやすくなる。 この場 合にも ECの混合が有効であり、 インターカレーシヨンが起こりにくくなる。 陰ィォ ンのインターカレーシヨンが起こりにくくするには、 より好ましくは EC 10%から 70%程度である。 また、 その他の非水溶媒としては、 テトラヒ ドロフラン （THF) 、 メチルテトラ ヒ ドロフラン （Me THF) 、 メチルホルムアミ ド、 メチルアセテート、 ジメチルェ 一テル （DME) 、 γ—ブチルラク トン （GB L) 、 ジメチルカーボネート （DM C) 、 ァセトニトリル （AN) 、 スルホラン （S L) 、 あるいは分子の一部にフッ化 物を含有するこれら非水溶媒からなる群から選ばれる少なくとも 1種を選ぶことがで さる。 上記正極及び負極を浸漬する電解液としては、 上記非水溶媒に溶質を溶解させたも のを用いることができる。 電解液中で作用する陰イオンとしては、 4フッ化ホウ酸ィ オン （B F4— ) 、 6フツイヒリン酸イオン （P F6— )、 過塩素酸イオン （C 104一） 、 6フッ化ヒ素 （A s F6— ) 、 6フッ化アンチモン （S b F6— ) 、 ペルフルォロメチ ルスルホニル (C F 3 S O2~) 、 ペルフルォロメチルスルホナト （CF3SO3— ) 力 らなる群から選ばれる少なくとも一種等を挙げることができる。 また、 陽イオンとしては、 トリェチルメチルアンモニゥムイオン （TEMA) 、 ト リメチルアルキルアンモニゥムであってアルキル基の炭素数が 2から 10であるアン モニゥムイオン等の対称、 非対称の四級アンモニゥムイオン、 ェチルメチルイミダゾ リウム等のイミダゾリウム誘導体イオン、 スピロ一 （1 , 1， ） ビピロリジニゥム (SBP) 、 ジメチルピロリジニゥム、 ジェチルピロリジニゥム、 ェチルメチルピロ リジニゥム等のピロリジニゥム化合物、 テトラメチルホスホニゥム、 テトラエチルホ スホニゥム、 リチウムイオンからなる群から選ばれる少なくとも一種等を挙げること ができる。 . その他、 キャパシタを構成するための、 セパレータ、 集電体等は、 通常、 キャパシ タに用いられているものを採用することができる。 In particular, a mixed solvent of ethylene carbonate and propylene carbonate is preferable. For example, in a mixed solvent bath of about £ 5% by volume (hereinafter, the solvent indicates volume% unless otherwise specified), depending on the anion intercalation. An increase in voltage is observed. For a given force S, a mixing ratio of EC 5% or more is desirable. The upper limit is not particularly limited, but in the case of 100% EC, when tetraethyl methyl ammonium ion (TEMABF 4 ) is used as the electrolyte salt, it is about 1.5 mol Z 1. However, it does not work as a capacitor because it consolidates. Even when not consolidated, the low-temperature characteristics are deteriorated, so about 80% of EC 70 is desirable as the upper limit mixing ratio. If the weight of the activated carbon is increased, the capacity increases, but anion intercalation tends to occur. In this case as well, EC mixing is effective and intercalation is less likely to occur. To make negative intercalation difficult to occur, EC is preferably about 10% to 70%. Other non-aqueous solvents include tetrahydrofuran (THF), methyltetrahydrofuran (Me THF), methylformamide, methyl acetate, dimethyl ether (DME), γ-butyl lactone (GBL), dimethyl It is possible to select at least one selected from the group consisting of carbonate (DMC), acetonitrile (AN), sulfolane (SL), and these non-aqueous solvents containing a fluoride in a part of the molecule. As the electrolytic solution for immersing the positive electrode and the negative electrode, a solution obtained by dissolving a solute in the non-aqueous solvent can be used. Anions that act in the electrolyte include tetrafluoroborate ion (BF 4 —), 6 fluhiphosphate ion (PF 6 —), perchlorate ion (C 10 4 ), arsenic hexafluoride ( A s F 6 —), antimony hexafluoride (S b F 6 —), perfluoromethylsulfonyl (CF 3 SO 2 ~), perfluoromethyl sulfonate (CF 3 SO 3 —) force And at least one selected from the group consisting of: Cations include triethyl methyl ammonium ion (TEMA), trimethyl alkyl ammonium ion and ammonium ions having an alkyl group with 2 to 10 carbon atoms, such as symmetric and asymmetric quaternary ammonium ions. Ion, imidazolium derivative ions such as ethyl ion And at least one selected from the group consisting of lithium, tetraethylphosphine, and lithium ion. In addition, separators, current collectors, etc. that are used for capacitors can be those usually used for capacitors.
以下に本発明の実施例、 比較例を示すが、 これらは本発明を限定するものではない。 比較例 1  Examples of the present invention and comparative examples are shown below, but these do not limit the present invention. Comparative Example 1
(正極の製造）  (Manufacture of positive electrode)
黒鉛化度 90%、 B ET表面積 1 6m2Zgの黒鉛 2 Omgと、 テフロン化ァセチ レンブラック （TAB) 5m gを、 軽くめのう乳鉢中で混合したのち、 スパーテルで シート状に成形して、 正極を得た。 Graphite 90%, B ET surface area 16 m 2 Zg of graphite 2 Omg and Teflonated acetylene black (TAB) 5 mg are mixed in a light agate mortar and then molded into a sheet with a spatula. Got.
(負極の製造） (Manufacture of negative electrode)
比表面積が 1 700m2Zgの水蒸気賦活活性炭 2 Omgとテフロン化アセチレン ブラック （TAB) 5mgを、 軽くめのう乳鉢中で混合したのち、 スパーテルでシ一 ト状に成形して、 負極を得た。 The specific surface area of 1 700 meters 2 Zg steam activated carbon 2 Omg Teflon acetylene black (TAB) 5 mg of lightly were mixed in an agate mortar, molded into sheet one bets like a spatula to obtain a negative electrode.
(キャパシタの製造） (Manufacture of capacitors)
上記正、 負極とセパレータ （材質：ガラス繊維） 、 及び溶媒としてプロピレンカー ボネート （PC) を含み、 溶質として TEMAP Ffi又は S B P P F6を 1— 2mo 1 dm3含む電解液を備えたキャパシタを乾燥雰囲気中で製作し、 比較例 1のキャパ シタ （試料 A) を得た。 実施例 1 The above positive, negative electrode, separator (material: glass fiber), and propylene carbonate (PC) as a solvent, TEMAP F fi or SBPPF 6 as the solute 1-2mo 1 A capacitor with an electrolyte containing dm 3 was fabricated in a dry atmosphere, and the capacitor of Comparative Example 1 (Sample A) was obtained. Example 1
電解液の溶媒として、 プロピレンカーボネート （PC) の代わりに、 プロピレン力 ーボネート （PC) 75%、 エチレンカーボネート （EC) 25%のものを用いたほ かは、 比較例 1と同様にして、 実施例 1のキャパシタ （試料 B) を得た。 実施例 2  The same procedure as in Comparative Example 1 was used except that propylene carbonate (PC) 75% and ethylene carbonate (EC) 25% were used instead of propylene carbonate (PC) as the solvent for the electrolyte. 1 capacitor (sample B) was obtained. Example 2
電解液の溶媒として、 プロピレンカーボネート （PC) の代わりに、 プロピレン力 ーボネート （PC) 50%、 エチレンカーボネート （EC) 50%のものを用いたほ かは、 比較例 1と同様にして、 実施例 2のキャパシタ （試料 C) を得た。 実施例 3  In the same manner as in Comparative Example 1, instead of using propylene carbonate (PC) instead of propylene carbonate (PC), a solvent with 50% propylene carbonate (PC) and 50% ethylene carbonate (EC) was used. Two capacitors (sample C) were obtained. Example 3
電解液の溶媒として、 プロピレンカーボネート （PC) の代わりに、 プロピレン力 ーボネート （PC) 75%、 エチレンカーボネート （EC) 25%のものを用いたほ かは、 比較例 1と同様にして、 実施例 3のキャパシタ （試料 D) を得た。 実施例 4  The same procedure as in Comparative Example 1 was used except that propylene carbonate (PC) 75% and ethylene carbonate (EC) 25% were used instead of propylene carbonate (PC) as the solvent for the electrolyte. 3 capacitors (sample D) were obtained. Example 4
正極材料として、 黒鉛化度 90%の黒鉛の代わりに、 リチウムイオン電池正極用 (大阪ガス MCMB6-28) の黒鉛 （黒鉛化度 93%、 BET表面積 2m2ノ g) を用い たほかは、 実施例 2と同様にして、 実施例 4のキャパシタ （試料 E) を得た。 実施例 5 As the cathode material, instead of graphite with a graphitization degree of 90%, graphite for lithium ion battery cathode (Osaka Gas MCMB6-28) was used (93% graphitization degree, BET surface area 2m 2 ng). In the same manner as in Example 2, the capacitor (Sample E) of Example 4 was obtained. Example 5
正極材料として、 黒鉛化度 90%の黒鉛の代わりに、 リチウムイオン電池正極用 (日立化成 （株） MAG-D) (黒鉛化度 98%、 BET表面積 3m2/g) を用いたほ かは、 実施例 2と同様にして、 実施例 5のキャパシタ （試料 F) を得た。 実施例 6 Instead of graphite with a graphitization degree of 90% as a positive electrode material, we used lithium ion battery positive electrode (Hitachi Chemical Co., Ltd. MAG-D) (graphitization degree 98%, BET surface area 3m 2 / g) In the same manner as in Example 2, the capacitor (Sample F) of Example 5 was obtained. Example 6
正極材料として、 黒鉛化度 90%の黒鉛の代わりに、 天然黒鉛 （黒鉛化度 100%、 BET表面積lm2Zg) を用いたほかは、 実施例 2と同様にして、 実施例 6のキヤ パシタ （試料 G) を得た。 比較例 2 The positive electrode material of Example 6 was the same as Example 2 except that natural graphite (graphitization degree 100%, BET surface area lm 2 Zg) was used instead of graphite with a graphitization degree of 90% as the positive electrode material. (Sample G) was obtained. Comparative Example 2
正極材料として、 黒鉛化度 90%の黒鉛の代わりに、 リチウムイオン電池正極用 (大阪ガス MCMB6-28) の黒鉛 （黒鉛化度 93%) を用いたほかは、 比較例 1と同 様にして、 比較例 2のキャパシタ （試料 を得た。 比較例 3  As in the case of Comparative Example 1, except that graphite for the lithium ion battery cathode (Osaka Gas MCMB6-28) (graphite degree 93%) was used instead of graphite with a degree of graphitization 90% as the positive electrode material. The capacitor of Comparative Example 2 (Sample was obtained. Comparative Example 3
正極材料として、 黒鉛化度 90%の黒鉛の代わりに、 リチウムイオン電池正極用 (日立化成 （株） MAG-D) (黒鉛化度 98%) を用いたほかは、 比較例 1と同様に して、 比較例 3のキャパシタ （試料 K) を得た。 比較例 4  The same procedure as in Comparative Example 1 was used except that instead of graphite with a graphitization degree of 90%, a positive electrode material (Hitachi Chemical Co., Ltd. MAG-D) (graphitization degree 98%) was used as the positive electrode material. Thus, a capacitor (Sample K) of Comparative Example 3 was obtained. Comparative Example 4
正極材料として、 黒鉛化度 90%の黒鉛の代わりに、 天然黒鉛 （黒鉛化度 1 00 %) を用いたほかは、 比較例 1と同様にして、 比較例 4のキャパシタ （試料 L) を得 た。 実施例 7  The capacitor (Sample L) of Comparative Example 4 was obtained in the same manner as Comparative Example 1 except that natural graphite (graphitization degree 100%) was used instead of graphite with a graphitization degree of 90% as the positive electrode material. It was. Example 7
正極：負極の重量比を 1 : 1. 3とし、 電解液の溶媒として、 プロピレンカーボネ ート （PC) の代わりに、 プロピレンカーボネート （PC) 95%、 エチレンカーボ ネート （EC) 5%のものを用いたほかは、 比較例 1と同様にして、 実施例 7のキヤ パシタ （試料 M) を得た。 実施例 8  The positive electrode: negative electrode weight ratio is 1: 1.3, and the electrolyte solvent is propylene carbonate (PC) 95%, ethylene carbonate (EC) 5% instead of propylene carbonate (PC). A capacitor (sample M) of Example 7 was obtained in the same manner as in Comparative Example 1 except that was used. Example 8
正極：負極の重量比を 1 ： 2とし、 電解液の溶媒として、 プロピレンカーボネート (PC) の代わりに、 プロピレンカーボネート （PC) 90%、 エチレンカーボネー ト （E C ) 1 0 %のものを用いたほかは、 比較例 1と同様にして、 実施例 8のキャパ シタ （試料 N) を得た。 比較例 5 The weight ratio of the positive electrode: negative electrode is 1: 2, and instead of propylene carbonate (PC) as the solvent for the electrolyte, 90% propylene carbonate (PC), ethylene carbonate The capacitor (Sample N) of Example 8 was obtained in the same manner as Comparative Example 1 except that 10% (EC) was used. Comparative Example 5
正極 ： 負極の重量比を 1 ： 1 . 3としたほかは、 比較例 1と同様にして、 比較 例 5のキャパシタ （試料 O) を得た。  A capacitor (Sample O) of Comparative Example 5 was obtained in the same manner as Comparative Example 1 except that the weight ratio of the positive electrode to the negative electrode was set to 1: 1.3.
実施例 1〜8、 比較例 1〜5のキャパシタの構成をまとめて、 表 1に示す。 表 1  Table 1 summarizes the capacitor configurations of Examples 1 to 8 and Comparative Examples 1 to 5. table 1
Figure imgf000010_0001
実施例 1〜8 (試料 B〜G、 M、 N) 、 比較例：！〜 5 (A、 J〜L、 O ) で得られ たキャパシタの黒鉛正極へのァニオンへのィンタ一力レーション （層間化合物の生 成） は黒鉛の （0 0 2 ) 面のピーク位置の変化から評価した。 (充放電試験）
Figure imgf000010_0001
Examples 1 to 8 (Samples B to G, M, N), Comparative Example:! ~ 5 (A, J ~ L, O) Intermittent force on the anion (interlayer compound formation) on the graphite positive electrode of the capacitor obtained from the change of the peak position of the (0 0 2) plane of the graphite evaluated. (Charge / discharge test)
上記のキャパシタ （試料 A〜0) に対して、 1 m Aの定電流で充電電流を印加した 所定の電圧に達したのちに、 その電圧で 2分間電圧を維持しながら、 X 線回折装置で 測定をする （層間化合物の生成が認められた電圧を測定する） 。  Applying a charging current at a constant current of 1 mA to the above capacitors (samples A to 0) After reaching a predetermined voltage, the voltage is maintained at that voltage for 2 minutes while using an X-ray diffractometer. Measure (measure the voltage at which the formation of intercalation compounds was observed).
その試験結果を表 2に示す。  The test results are shown in Table 2.
Figure imgf000011_0001
表 2より、 黒鉛を正極に用い、 エチレンカーボネートを含有する溶媒を用いた本発 明のキャパシタは、 インターカレーシヨン反応が起こりにくいキャパシタであり、 充 電圧を 3 V 以上にすることが可能である。 また、 充放電に伴うインターカレーシヨン、 脱インターカレーシヨンにより黒鉛格子の膨張、 収縮が、 きわめて起こりにくいので 耐久寿命が長くなることがわかった。 また、 試料 Lの充放電曲線を図 1に示した。 図から、 天然黒鉛を正極に用い、 溶媒 をプロピレンカーボネートにすると 2 . 5 V から 2 0 = 2 6 ° 付近に新たなピークが 出現し層間化合物が生成することがわかる。 このピーク位置は、 充電とともに低角度 に移動する。 同時に 3 0— 3 2 ° 付近にも新たなピークが出現し、 層間化合物が生成 することがわかる。 さらに、 表 2及び図 1より、 黒鉛化度の高い黒鉛を正極に用い、 溶媒をプロピレンカーボネー卜にすると、 ァ-オンのィンタ一力レーションが容易に 起こり、 一方、 黒鉛化度の高い黒鉛を正極に用いても、 エチレンカーボネートを含有 する溶媒を用いた本発明のキャパシタは、 ァニオンのィンタ一力レーションが起こり にくいことがわかった。 比較例 5に示すように、 正極に対する負極の重量比を 1以上にすると、 黒鉛へのァ 二オンのインターカレーションが起こりやすくなる。 しかし EC 5%程度の混合で、 インターカレーシヨンが起こりにくくなることが認められた （実施例 7) 。 実用上は 実施例 8にあるように 10 %程度以上の混合が望ましい。
Figure imgf000011_0001
From Table 2, the capacitor of the present invention using graphite as a positive electrode and a solvent containing ethylene carbonate is a capacitor in which an intercalation reaction hardly occurs, and the charge voltage can be increased to 3 V or more. . It was also found that the intercalation and de-intercalation associated with charging / discharging would cause the graphite lattice to expand and contract very easily, thus extending the durability life. Figure 1 shows the charge / discharge curve of Sample L. From the figure, it can be seen that when natural graphite is used for the positive electrode and the solvent is propylene carbonate, a new peak appears from 2.5 V to around 20 ° = 26 ° and an intercalation compound is formed. This peak position moves at a low angle with charging. At the same time, a new peak appears around 30 ° –32 °, indicating that an intercalation compound is formed. Furthermore, from Table 2 and Figure 1, graphite with a high degree of graphitization was used for the positive electrode, When propylene carbonate is used as the solvent, the onion interfering easily occurs. On the other hand, even when graphite having a high degree of graphitization is used for the positive electrode, the capacitor of the present invention using the solvent containing ethylene carbonate is used. It was found that the Anion's Interplay is unlikely to occur. As shown in Comparative Example 5, when the weight ratio of the negative electrode to the positive electrode is 1 or more, anion intercalation into graphite tends to occur. However, it was confirmed that intercalation was less likely to occur when EC was mixed at about 5% (Example 7). For practical use, as in Example 8, it is desirable to mix approximately 10% or more.
3. 5 Vまでの充電を行うと、 その放電容量は、 正極に対する負極の重量比が 1の 実施例 1、 比較例 1の場合は、 3 OmAh/g、 平均電圧を 2. 7Vとするとェネル ギー密度は 7 lWh/k gであるが、 正極に対する負極の重量比が 2の実施例 8の場 合は容量が、 5 OmAh/g、 エネルギー密度 1 35WhZk g (いずれも正極重 量あたりの容量、 エネルギー密度） で約 2倍という大きなエネルギー密度となる。 黒鉛を正極に用い、 エチレンカーボネートを含有する溶媒を用いた本発明のキャパ シタは、 インターカレーシヨン反応が起こりにくいキャパシタであり、 充電圧を 3 V 以上にすることが可能であるとともに、 負極重量を増加させることが可能となり、 結 果的にエネルギー密度の上昇が可能となった。 このことは E Cを混合溶媒の基本溶媒 とすることにより、 始めて可能となったものである。 産業上の利用可能性 3. When charging up to 5 V, the discharge capacity is 3 OmAh / g and the average voltage is 2.7 V in Example 1 where the weight ratio of the negative electrode to the positive electrode is 1, and in Comparative Example 1. The energy density is 7 lWh / kg, but in Example 8 where the weight ratio of the negative electrode to the positive electrode is 2, the capacity is 5 OmAh / g, and the energy density is 1 35 WhZk g (both capacity per positive electrode weight, Energy density) is approximately twice as large. The capacitor of the present invention using graphite as a positive electrode and a solvent containing ethylene carbonate is a capacitor in which an intercalation reaction is unlikely to occur, and the charge pressure can be increased to 3 V or more. As a result, the energy density can be increased. This is possible for the first time by using EC as the basic solvent of the mixed solvent. Industrial applicability
本発明のキャパシタは、 静電容量が大きく、 しかも急速充放電が可能であるので、 電気自動車等の移動体用の電源、 無停電電源装置、 電気事業用の電力貯蔵システム等 に有用なものである。  Since the capacitor of the present invention has a large capacitance and can be rapidly charged and discharged, it is useful for a power source for a moving body such as an electric vehicle, an uninterruptible power supply, a power storage system for an electric utility, and the like. is there.

Claims

請求の範囲 The scope of the claims
1 . 黒鉛質材料を含有する正極、 非黒鉛質の炭素質材料を含有する負極、 及び非水電 解液を備えてなるキャパシタにおいて、 前記非水電解液の溶媒が、 エチレンカーボネ ートを含有することを特徴とするキャパシタ。 1. In a capacitor comprising a positive electrode containing a graphite material, a negative electrode containing a non-graphitic carbonaceous material, and a non-aqueous electrolyte, the solvent of the non-aqueous electrolyte contains ethylene carbonate. Capacitor characterized by that.
2 . 前記黒鉛質材料が、 黒鉛化度が 9 0 %以下であることを特徴とする請求の範囲第 1項に記載のキャパシタ 2. The capacitor according to claim 1, wherein the graphitic material has a graphitization degree of 90% or less.
3 . 前記非黒鉛質の炭素質材料が、 活性炭であることを特徴とする請求の範囲第 1項 に記載のキャパシタ。 3. The capacitor according to claim 1, wherein the non-graphitic carbonaceous material is activated carbon.
4 . 前記非水電解液が、 エチレンカーボネートと、 エチレンカーボネート以外の炭酸 エステル類、 ァセトニトリル又は γ—プチルラク トン類との混合溶媒を主溶媒とする ことを特徴とする請求の範囲第 1項〜第 3項のいずれか一項に記載のキャパシタ。 4. The non-aqueous electrolyte comprises, as a main solvent, a mixed solvent of ethylene carbonate and a carbonate other than ethylene carbonate, acetonitrile, or γ-butyl lactone. 4. The capacitor according to any one of items 3.
5 . 前記非水電解液が、 エチレンカーボネートとプロピレンカーボネートとの混合溶 媒を主溶媒とすることを特徴とする請求の範囲第 4項に記載のキャパシタ。 5. The capacitor according to claim 4, wherein the non-aqueous electrolyte contains a mixed solvent of ethylene carbonate and propylene carbonate as a main solvent.
PCT/JP2007/072597 2006-11-17 2007-11-15 Capacitor WO2008059990A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2008544222A JPWO2008059990A1 (en) 2006-11-17 2007-11-15 Capacitors

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2006311014 2006-11-17
JP2006-311014 2006-11-17

Publications (1)

Publication Number Publication Date
WO2008059990A1 true WO2008059990A1 (en) 2008-05-22

Family

ID=39401790

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2007/072597 WO2008059990A1 (en) 2006-11-17 2007-11-15 Capacitor

Country Status (2)

Country Link
JP (1) JPWO2008059990A1 (en)
WO (1) WO2008059990A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013146136A1 (en) * 2012-03-27 2013-10-03 住友精化株式会社 Electrolyte solution for capacitors, electric double layer capacitor, and lithium ion capacitor

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000173874A (en) * 1998-12-02 2000-06-23 Nichicon Corp Electrolytic solution for driving electric double-layered capacitor
JP2005294780A (en) * 2003-12-05 2005-10-20 Masayuki Yoshio Charge storage element and electric double-layer capacitor

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000173874A (en) * 1998-12-02 2000-06-23 Nichicon Corp Electrolytic solution for driving electric double-layered capacitor
JP2005294780A (en) * 2003-12-05 2005-10-20 Masayuki Yoshio Charge storage element and electric double-layer capacitor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013146136A1 (en) * 2012-03-27 2013-10-03 住友精化株式会社 Electrolyte solution for capacitors, electric double layer capacitor, and lithium ion capacitor
US9646773B2 (en) 2012-03-27 2017-05-09 Sumitomo Seika Chemicals Co., Ltd. Electrolyte solution for capacitors, electric double layer capacitor, and lithium ion capacitor

Also Published As

Publication number Publication date
JPWO2008059990A1 (en) 2010-03-04

Similar Documents

Publication Publication Date Title
CN107112600B (en) Aqueous electrolyte for electricity storage device and electricity storage device containing the same
JP4202334B2 (en) Electrochemical devices
US7241535B2 (en) Electrolyte for lithium-sulfur batteries and lithium-sulfur batteries comprising the same
JP4159954B2 (en) Non-aqueous electrolyte battery
US10033049B2 (en) Non-aqueous electrolyte for electrochemical devices, method for producing the same, and electrochemical device using the same
CN101578675B (en) Electric double layer capacitor
JP5378367B2 (en) Non-aqueous electrolyte and electrochemical device including the same
WO2017122597A1 (en) Aqueous electrolytic solution for electrical storage device, and electrical storage device including said aqueous electrolytic solution
US20040009393A1 (en) Electrolyte of lithium-sulfur batteries and lithium-sulfur batteries comprising the same
US20130136972A1 (en) Nonaqueous secondary battery electrode, nonaqueous secondary battery including the same, and assembled battery
TW200305174A (en) Material for electrolytic solutions and use thereof
KR20140004773A (en) Polyimide capacitance battery and manufacturing method thereof
TW201539834A (en) Non-aqueous electrolyte for lithium secondary battery and lithium secondary battery having the same
JP4904616B2 (en) Electrolytic solution and electrochemical element using the same
WO2017038796A1 (en) Electrolyte composition, secondary battery, and method for using secondary battery
JP5886606B2 (en) Layered compound and storage battery using the same
JP2010205695A (en) Energy storage device
WO2016006315A1 (en) Nonaqueous electrolytic solution including ester having 3,3,3-trifluoropropionate group and nonaqueous electrolyte battery using same
WO2001020698A1 (en) Electrochemical capacitor
JP4904950B2 (en) Electric double layer capacitor
WO2008059990A1 (en) Capacitor
JP5245864B2 (en) Power storage device
JP4190207B2 (en) Electrolytes for electrochemical devices, electrolytes or solid electrolytes thereof, and batteries
JP6831180B2 (en) Power storage device and its manufacturing method
KR101018142B1 (en) Non-aqueous electrolyte and secondary battery comprising the same

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 07832327

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2008544222

Country of ref document: JP

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 07832327

Country of ref document: EP

Kind code of ref document: A1