WO2014073221A1 - リチウム二次電池用電極およびリチウム二次電池 - Google Patents
リチウム二次電池用電極およびリチウム二次電池 Download PDFInfo
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- WO2014073221A1 WO2014073221A1 PCT/JP2013/050674 JP2013050674W WO2014073221A1 WO 2014073221 A1 WO2014073221 A1 WO 2014073221A1 JP 2013050674 W JP2013050674 W JP 2013050674W WO 2014073221 A1 WO2014073221 A1 WO 2014073221A1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/133—Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/04—Construction or manufacture in general
- H01M10/0431—Cells with wound or folded electrodes
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
- H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
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- H—ELECTRICITY
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/64—Carriers or collectors
- H01M4/70—Carriers or collectors characterised by shape or form
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2220/00—Batteries for particular applications
- H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
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- 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
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Definitions
- the present invention relates to an electrode for a lithium secondary battery and a lithium secondary battery using the electrode.
- the lithium secondary battery in which the negative electrode is formed using a material capable of occluding and releasing lithium ions can suppress the precipitation of dendrite compared to the lithium battery in which the negative electrode is formed using metallic lithium, It has been put on the market as a battery with improved safety. In recent years, this lithium secondary battery is being developed for in-vehicle use, and regenerative capacity, that is, quick chargeability, has become a problem. As countermeasures, (1) battery resistance can be reduced, (2) the lithium ion inter-deintercalation reaction can prevent the precipitation of metallic lithium, and the inter-deintercalation reaction can proceed quickly. ing.
- the present invention has been made in order to cope with the above-described problems.
- the battery can be quickly charged in a very short time, for example, within one minute, and fully charged in one minute.
- An object is to provide a possible positive electrode and negative electrode for a lithium secondary battery, and a lithium secondary battery using these lithium secondary battery electrodes.
- the present invention relates to a lithium secondary battery in which lithium ion is repeatedly occluded and released by infiltrating or immersing an organic electrolyte in a wound or laminated electrode group through a separator between a positive electrode and a negative electrode. It is an electrode for lithium secondary batteries used for the above.
- the positive electrode is formed of a positive electrode current collector foil and a positive electrode active material layer formed on the positive electrode current collector foil
- the negative electrode is formed of a negative electrode current collector foil and the negative electrode.
- a negative electrode active material layer formed on the current collector foil is formed of a positive electrode current collector foil and a negative electrode.
- the active material that forms the positive electrode and negative electrode active material layers is an active material having at least one phase selected from a graphene phase and an amorphous phase as a surface layer, and these positive and negative electrode active materials formed on a current collector foil
- the electrode for a lithium secondary battery of the present invention is characterized in that a layer of activated carbon is further formed on the surface of the layer.
- the activated carbon has a specific surface area of 1000 m 2 / g or more.
- the positive electrode current collector foil and / or the negative electrode current collector foil constituting the electrode for the lithium secondary battery of the present invention is a protrusion penetrating the current collector foil and projecting to at least one foil surface side of the current collector foil A plurality of through-holes having a portion are formed.
- the lithium secondary battery of the present invention uses the positive electrode and the negative electrode for the lithium secondary battery, and permeates or immerses the organic electrolyte in an electrode group formed by winding or stacking the separator between the electrodes. It is a secondary battery that repeatedly stores and releases lithium ions.
- the electrode for the lithium secondary battery of the present invention forms an activated carbon layer on the surface of the positive and negative electrode active material layers, and it is particularly preferable to form an activated carbon layer having a specific surface area of 1000 m 2 / g or more, A lithium secondary battery can be obtained that can be fully charged in an extremely short charging time of 1 minute or less with respect to the electrode not formed with the activated carbon layer.
- this lithium secondary battery can prevent the deposition of metallic lithium dendrite, particularly on the surface of the negative electrode active material, during ultra-rapid charging.
- FIG. 1 is a cross-sectional view of one negative electrode plate including a foil-like current collector having a plurality of through holes having protrusions, an active material layer, and an activated carbon layer.
- the foil-like current collector 1a is provided with a protruding hole 1c having a protruding portion 1b around the through hole.
- An active material layer 1d is formed on the surface of the foil-shaped current collector 1a, and an activated carbon layer 1e is formed on the surface of the active material layer 1d.
- the activated carbon layer 1e may be the entire surface of the active material layer 1d or may be formed on a part of the surface.
- the active material forming the active material layer 1d examples include a carbon material having at least one phase selected from a graphene phase and an amorphous phase as a surface layer.
- the protrusion part 1b and the protrusion hole 1c may be formed over the whole surface of a collector, and may be formed in part leaving the flat foil part of a non-protrusion surface in part. Preferably, it is better to be formed in part due to the strength of the current collector foil in battery manufacture. In particular, it is preferable to leave flat foil portions without the protruding holes 1c without forming the protruding holes 1c in both width portions of the current collector foil.
- the foil cross-sectional shape of the protruding hole 1c any shape such as a polygonal pyramid, a cylindrical shape, a conical shape, or a combination of these shapes can be used.
- a conical shape is more preferable from the viewpoint of the processing speed, the processing shot life of the processing jig, and the possibility of generation of cutting powder and peeling powder after processing the tip of the protruding hole.
- this protrusion hole 1c is a through-hole formed by breaking through a current collection foil, it is preferable since the current collection effect is improved.
- the through-hole formed by breaking through the current collector foil has a large current charge / discharge compared to the through-hole formed in the current collector foil by punching or the unevenness formed by embossing. Excellent durability such as internal short circuit during cycling.
- the through hole is a circular hole having a diameter t 2 of 50 to 150 ⁇ m, the height t 1 of the protrusion is 50 to 400 ⁇ m, and the distance t 3 between adjacent through holes is 300 to 2000 ⁇ m.
- the carbon material forming the active material layer 1d has at least one phase selected from a graphene phase and an amorphous phase as a surface layer.
- the graphene phase refers to a single plane 6-membered ring structure of sp 2 -bonded carbon atoms
- the amorphous phase refers to a structure in which this 6-membered ring structure is three-dimensionally configured.
- Examples of the carbon material include graphite-based carbon materials including artificial graphite, natural graphite, graphitizable carbon materials, and amorphous carbon materials, acetylene black, ketjen black, conductive carbon black-based powders including graphite crystals, and Examples include at least one carbon material selected from conductive carbon fibers. These carbon materials are substances whose specific surface area is extremely smaller than that of the activated carbon and whose characteristics are different from those of the activated carbon.
- Graphite-based carbon material is a carbon material that easily develops on the surface a graphite structure, which is a hexagonal network plane composed of carbon atoms, a so-called graphene phase laminated with regularity, when heat treatment is performed in an inert atmosphere, So-called soft carbon can be used.
- the conductive carbon fiber preferably contains at least one of carbon fiber, graphite fiber, vapor grown carbon fiber, carbon nanofiber, and carbon nanotube.
- the fiber diameter of the carbon fiber is preferably 5 nm to 200 nm, and more preferably 10 nm to 100 nm.
- the fiber length is preferably 100 nm to 50 ⁇ m, more preferably 1 ⁇ m to 30 ⁇ m.
- the activated carbon that can be used in the present invention can be obtained by heat-treating a carbide produced from sawdust, wood chips, charcoal, coconut husk charcoal, coal, phenol resin, rayon, etc. at a high temperature close to about 1000 ° C.
- the activated carbon that can be used in the present invention preferably has a specific surface area of 1000 m 2 / g or more.
- the specific surface area is preferably 1500 to 2200 m 2 / g.
- the specific surface area is a value measured using the BET three-point method. Examples of commercial products of activated carbon can be used, Kureha Chemical Company MSP-20 N Part (specific surface area of 2100 m 2 / g), Taiko activated carbon C type Futamura Chemical Co., Ltd. (specific surface area of 1680m 2 / g) can be exemplified.
- the activated carbon layer 1e is formed on the surface of the active material layer 1d. It may be the entire surface of the active material layer 1d or a part of the surface. Preferably, it is the entire surface of the active material layer 1d.
- the thickness of the activated carbon layer 1e is 0.1 to 5 ⁇ m, preferably 0.5 to 4 ⁇ m. When the thickness is within this range, the quick charge performance is improved. Examples of a method for forming the activated carbon layer 1e on the surface of the active material layer 1d include a coating method such as a roll coater or a spray method.
- the positive electrode of the present invention includes, as an active material, a layered or spinel-structured lithium-containing metal oxide or a solid solution thereof, an olivine-structured lithium-containing metal phosphate compound or a lithium-containing metal silicate, and their A composite layer comprising a fluoride and a lithium-containing compound such as sulfur as a main material, a carbon material layer similar to the negative electrode material described above being formed on the surface layer of the material, and comprising a binder and a conductive material Is formed on an aluminum current collector foil as a perforated protruding foil similar to the negative electrode.
- a composite material including a main material such as the lithium-containing metal oxide and a conductive material is referred to as a positive electrode active material. Further, an activated carbon layer similar to the negative electrode is formed on the surface of the composite material layer.
- the lithium-containing metal phosphate compound include LiFePO 4 , LiCoPO 4 , and LiMnPO 4
- examples of the siliceous oxide include LiFeSiO 4 .
- the fluoride include Li 2 FePO 4 ⁇ F.
- the lithium-containing compound include LiS 4 , LiTi 2 (PO 4 ) 3 , LiFeO 2 and the like.
- LiCoO 2 , Li (Ni / Co / Mn) O 2 , LiMn 2 O 4 , and LiFePO 4 are preferably used in terms of electrochemical characteristics, safety, and cost.
- a carbon material layer having at least one phase selected from a graphene phase and an amorphous phase is formed on the surface of each active material.
- the conductive material include carbon black and carbon nanotubes. Then, an activated carbon layer is formed on the surface of the active material mixture layer to which the binder has been added.
- a separator that can be used for a lithium secondary battery is one that electrically insulates a positive electrode and a negative electrode to hold an electrolytic solution.
- the separator include synthetic resin films, fibers or inorganic fibers. Specific examples thereof include polyethylene and polypropylene films, woven and nonwoven fabrics made of these resins, glass fibers and cellulose fibers. And so on.
- the lithium secondary battery it is preferable to use a non-aqueous electrolyte containing a lithium salt, an ion conductive polymer, or the like as the electrolyte in which the electrode group described above is immersed.
- non-aqueous solvent in the non-aqueous electrolyte containing a lithium salt examples include ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), dimethyl carbonate (DMC), and methyl ethyl carbonate (MEC).
- lithium salts that can be dissolved in the non-aqueous solvent include lithium hexafluorophosphate (LiPF 6 ), lithium borotetrafluoride (LiBF 4 ), and lithium trifluoromethanesulfonate (LiSO 3 CF 4 ).
- the binder is a material that is physically and chemically stable under the atmosphere in the battery, and includes a fluorine-containing resin such as polytetrafluoroethylene, polyvinylidene fluoride, and fluorine rubber, polypropylene, A thermoplastic resin such as polyethylene can be used. Acrylic resin materials, styrene / butadiene based materials and the like can also be used.
- Electrode Example 1 and Electrode Comparative Example 1 In order to investigate the effect of the negative electrode of the present invention, a negative electrode for a lithium secondary battery was produced by the following method.
- a carbon material for the negative electrode 1 part by mass of a carbon nanotube conductive material is added to an artificial graphite surface layer formed of a carbon material, and a styrene / butadiene-based material (SBR) solution is mixed as a binder in a carboxymethylcellulose (CMC) aqueous solution.
- SBR styrene / butadiene-based material
- Electrode Example 1 of the present invention activated carbon having a specific surface area of 2100 m 2 / g, polyvinyl alcohol binder, and carboxymethyl cellulose (CMC) on both surfaces of the negative electrode coated with a thickness of 2 ⁇ m.
- the slurry solution prepared in (1) was roll-coated and dried.
- the negative electrode for lithium secondary batteries was obtained by pressing. The total thickness of the negative electrode when pressed was 124 ⁇ m.
- the negative electrode of the same structure as the electrode Example 1 was set as the electrode comparative example 1 except not having apply
- Electrode Example 2 As foil current collector of the negative electrode, shown in Figure 1, a circular hole with a diameter t 2 is 100 ⁇ m through-hole, the height t 1 is 45 ⁇ m protrusions, the distance between adjacent through-holes t 3 A copper foil having a thickness of 300 ⁇ m and a thickness of 10 ⁇ m was prepared. A negative electrode having the same configuration as that of the electrode example 1 was manufactured in the same manner as the electrode example 1 except that the foil-shaped current collector was used, and the electrode example 2 was obtained.
- Electrode Example 3 and Electrode Example 4 A negative electrode having the same configuration as that of the electrode example 1 was manufactured in the same manner as the electrode example 1 except that activated carbon having a specific surface area of 1680 m 2 / g was used, and this was designated as electrode example 3. Further, a negative electrode having the same configuration as that of the electrode example 1 was manufactured in the same manner as the electrode example 1 except that activated carbon having a specific surface area of 800 m 2 / g was used, and the electrode example 4 was obtained.
- the positive electrode used as the counter electrode of the negative electrode manufactured in the electrode example 1, the electrode example 2, the electrode example 3, the electrode example 4, and the electrode comparative example 1 was manufactured by the following method. First, olivine type lithium iron phosphate coated on the surface with conductive carbon having a secondary particle diameter of 2 to 3 ⁇ m is used as an active material, and 10 parts by mass of conductive carbon as a conductive agent is added to 84 parts by mass of the active material. A mixture of conductive carbon fiber bodies and 6 parts by mass of polyvinylidene fluoride as a binder were added. To this, N-methylpyrrolidone was added as a dispersion solvent and kneaded to prepare a positive electrode mixture (positive electrode slurry).
- Electrode Example 5 and Electrode Comparative Example 2 A smooth aluminum foil having a thickness of 20 ⁇ m and a width of 150 mm is prepared. And after apply
- Electrode Example 6 As the foil-like current collector of the positive electrode, the through hole shown in FIG. 1 is a circular hole having a diameter t 2 of 100 ⁇ m, the height t 1 of the protrusion is 60 ⁇ m, and the distance t 3 between adjacent through holes is 300 ⁇ m.
- a positive electrode for a lithium secondary battery having an activated carbon layer formed on the surface was manufactured in the same manner as in electrode example 5, except that a foil with a hole having a hole of 20 ⁇ m was used. .
- Battery Example 1 to Battery Example 5, Battery Comparative Example 1 A 3.4 V-5 Ah aluminum laminated film pack type lithium ion battery was produced using the positive electrode and the negative electrode for lithium secondary batteries produced in the above electrode examples and electrode comparative examples.
- the electrolytic solution a solution in which 1 mol / l of lithium hexafluorophosphate (LiPF6) was dissolved in a mixed solution of ethylene carbonate (EC), methyl ethyl carbonate (MEC), and dimethyl carbonate (DMC) was used.
- EC ethylene carbonate
- MEC methyl ethyl carbonate
- DMC dimethyl carbonate
- PE polyethylene
- Table 1 shows configurations of electrode examples and electrode comparative examples
- Table 2 shows combinations of positive electrodes and negative electrodes.
- the electrode or battery of the present invention can be charged rapidly within 1 minute at room temperature, and can be charged and discharged at a low temperature. This is because, especially in the activated carbon layer on the negative electrode surface, a large amount of lithium ions that have moved to the surface due to large current charging are first adsorbed like a capacitor and do not cause precipitation of metallic lithium. This is considered to be inserted between the active material carbon layers inside.
- the electrode comparative example 1 white crystals were formed on the entire surface, metal lithium was deposited, and lithium carbonate was formed or the direct electrolyte solution This is considered to be because lithium carbonate was produced by the decomposition reaction with the electrolytic solution.
- the use of a current collector foil having a protruding through hole and the application of the activated carbon layer and the through hole to both the positive electrode and the negative electrode plate further increase the synergistic effect. This is thought to be due to the rapid inter-deintercalation of lithium ions at both poles during rapid charging.
- the test results using a polyvinyl alcohol binder for the activated carbon layer on the negative electrode surface were shown, but similar results were also obtained with a binder made of styrene-butadiene (SBR) resin or polyacrylic resin.
- SBR styrene-butadiene
- lithium iron phosphate was used for the positive electrode and a carbon material was used for the negative electrode.
- another lithium oxide was used on the positive electrode side or when another negative electrode was used.
- the electrode of the lithium secondary battery of the present invention is capable of ultra-rapid charging, has a high capacity even at a low temperature, and is always in a fully charged state by improving the regenerative capacity without increasing the battery capacity. It has become possible to expand to industrial batteries.
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Abstract
Description
このリチウム二次電池用電極において、上記正電極は、正極集電箔とこの正極集電箔上に形成される正極活物質層とから形成され、上記負電極は、負極集電箔とこの負極集電箔上に形成される負極活物質層とから形成される。上記正極および負極活物質層を形成する活物質がグラフェン相およびアモルファス相から選ばれた少なくとも1つの相を表面層として有する活物質であり、集電箔上に形成されたこれら正および負極活物質層の表面にさらに活性炭の層が形成されていることを本発明のリチウム二次電池用電極は特徴とする。特に、該活性炭の比表面積が1000m2/g以上であることを特徴とする。
図1は突出部を有する複数の貫通孔を備えた箔状集電体、活物質層および活性炭の層からなる1枚の負極板の断面図である。
箔状集電体1aは、貫通孔周囲に突出部1bを有する突出孔1cが設けられている。そしてこの箔状集電体1aの表面に活物質層1dが形成され、この活物質層1dの表面に活性炭の層1eが形成されている。活性炭の層1eは、活物質層1dの全表面であっても、あるいは一部の面に形成されている場合であってもよい。
活物質層1dを形成する活物質は、グラフェン相およびアモルファス相から選ばれた少なくとも1つの相を表面層として有する炭素材が挙げられる。
なお、突出部1bと突出孔1cとは、集電体の全面にわたって形成されていても、また一部に非突出面の平坦な箔部を残して一部分に形成されていてもよい。好ましくは電池製造上の集電箔の強度の関係で、一部に形成されている方がよりよい。特に、集電箔の両幅部分には突出孔1cを形成することなく、突出孔1cのない平坦な箔部分を残すことが好ましい。
また、この突出孔1cは、集電箔を突き破って形成される貫通孔であることが集電効果を向上させるので好ましい。集電箔を突き破って形成される貫通孔は、集電箔にパンチング加工で形成される貫通孔またはエンボス加工で形成される凹凸に比較して、リチウム二次電池としたときの大電流充放電に優れ、サイクル時の内部短絡等の耐久性に優れる。
黒鉛系炭素材は、不活性雰囲気中で加熱処理を施したとき、炭素原子が構成する六角網平面、いわゆるグラフェン相が規則性をもって積層した構造である黒鉛構造を表面に発達させやすい炭素材料、いわゆるソフトカーボンを使用することができる。
導電性カーボン繊維は、カーボン繊維、グラファイト繊維、気相成長炭素繊維、カーボンナノファイバーおよびカーボンナノチューブのうちの少なくとも1種類を含有することが好ましい。カーボン繊維の繊維径としては5nm~200nmであることが好ましく、10nm~100nmであることがより好ましい。また、繊維長が100nm~50μmであることが好ましく、1μm~30μmであることがより好ましい。
また、負極材構成材料の配合割合で、導電材は1~12質量%、好ましくは4~8質量%配合することができる。
使用できる活性炭の市販品としては、クレハケミカル社製のMSP-20N品番(比表面積が2100m2/g)、フタムラ化学社製の太閤活性炭Cタイプ(比表面積が1680m2/g)が例示できる。
活性炭の層1eの厚さは0.1~5μm、好ましくは0.5~4μmである。厚さがこの範囲にあると、急速充電性能が向上する。
活物質層1dの表面に活性炭の層1eを形成する方法としては、ロールコーター等の塗工もしくはスプレー方式等が挙げられる。
これらの中で、電気化学特性、安全性やコスト面で、LiCoO2、Li(Ni/Co/Mn)O2、LiMn2O4、LiFePO4を用いることが好ましい。また各活物質の表面にグラフェン相およびアモルファス相から選ばれた少なくとも1つの相を有する炭素材層が形成されていることが好ましい。
また導電材としてはカーボンブラックやカーボンナノチューブが挙げられる。そしてバインダーを加えた活物質合材層の表面に活性炭層を形成する。
また、上記非水溶媒に溶解できるリチウム塩としては、六フッ化リン酸リチウム(LiPF6)、ホウ四フッ化リチウム(LiBF4)、トリフルオロメタンスルホン酸リチウム(LiSO3CF4)等が挙げられる。
電極実施例1および電極比較例1
本発明の負電極における効果を調べるために以下の方法でリチウム二次電池用負電極を製造した。
負極材の炭素材として、炭素材を人造黒鉛表面層形成させたものにカーボンナノチューブ導電材を1質量部添加し、カルボキシメチルセルロース(CMC)水溶液にバインダーとしてスチレン・ブタジエン系材料(SBR)溶液を混合して、CMCやSBRの固形部材として3質量部(CMC/SBR固形分比=1/2質量部)添加してスラリーを作製した。
次に貫通孔を設けない平滑面の銅箔に上記スラリーを75g/m2の塗工量で塗工して乾燥を行なった。続いて、本発明の電極実施例1として、厚さ2μmで上記塗工された負電極の両表面に、2100m2/gの比表面積を有する活性炭とポリビニールアルコールバインダーとカルボキシメチルセルロース(CMC)とで作製したスラリー溶液をロール塗布して乾燥した。その後、プレス処理をしてリチウム二次電池用の負電極を得た。プレスした時の負電極総厚さは124μmであった。また、前述の活性炭を塗布していない以外は、電極実施例1と同一構成の負電極を電極比較例1とした。
負電極の箔状集電体として、図1に示す、貫通孔の直径t2が100μmの円孔であり、突出部の高さt1が45μmであり、隣接する貫通孔との距離t3が300μmであり、厚さが10μmの銅箔を準備した。この箔状集電体を用いる以外は、電極実施例1と同一構成の負電極を電極実施例1と同様の方法で製造して電極実施例2とした。
1680m2/gの比表面積を有する活性炭を用いる以外は電極実施例1と同一構成の負電極を電極実施例1と同様の方法で製造して電極実施例3とした。
また、800m2/gの比表面積を有する活性炭を用いる以外は電極実施例1と同一構成の負電極を電極実施例1と同様の方法で製造して電極実施例4とした。
まず、二次粒子径が2~3μmの導電性カーボンが表面にコートされたオリビン型リン酸鉄リチウムを活物質とし、該活物質84質量部に、導電剤として10質量部の導電性カーボンおよび導電性カーボン繊維体の混合体と、結着剤として6質量部のポリフッ化ビニリデンを添加した。これに分散溶媒として、N-メチルピロリドンを添加し、混練して、正極合剤(正極スラリー)を作製した。
20μm厚さで、150mm幅の平滑アルミニウム箔を準備する。そして前述の正極スラリーを該アルミニウム箔の両面に塗工乾燥をしてから、電極実施例1の負極製造に用いた活性炭スラリーをこの正電極表面に塗布してリチウム二次電池用正電極を製造した。アルミニウム箔の両面に正極スラリーを塗工乾燥後、プレスした時の正電極の総厚さは160μmであった。この正電極を電極実施例5とする。また、前述の活性炭スラリーを塗布しない以外は、電極実施例5と同一構成の正電極を電極比較例2とした。
正極の箔状集電体として、図1に示す貫通孔の直径t2が100μmの円孔であり、突出部の高さt1が60μmであり、隣接する貫通孔との距離t3が300μmであり、厚さが20μmのアルミニウム箔の穴あき突起状の箔を用いる以外は、電極実施例5と同一の方法で、表面に活性炭層が形成されたリチウム二次電池用正電極を製造した。
上記各電極実施例および電極比較例で製造されたリチウム二次電池用正電極および負電極を用いて3.4V-5Ahのアルミラミネートフィルムパック式リチウムイオン電池を作製した。電解液にはエチレンカーボネート(EC)、メチルエチルカーボネート(MEC)、ジメチルカーボネート(DMC)溶媒を混合した溶液中に6フッ化リン酸リチウム(LiPF6)を1mol/l溶解したものを用いた。正・負電極のセパレータには、ポリエチレン(PE)樹脂製の厚さ40μmのフィルムを用いた。
電極実施例および電極比較例の構成を表1に、正電極および負電極の組み合わせを表2に示す。
また電池比較例1と電池実施例1、2、3および4とを比較すると、活性炭層があることで100ItAの超急速充電が可能となる効果は明白である。しかし、活性炭の比表面積が大きくなるに従って急速充電性能は向上しており、比表面積1000m2/g以上のものは性能が急激に上がっている。これは処理の活性炭層がグラファイト層に対して比表面積の比較的小さいものは接触抵抗体となり、大きいものに比して充電電流が流れにくかったためと考えられる。一方、正極での活性炭層の急速充電性への効果はあるものの、負極ほど顕著ではない。これは急速充電性能は負極支配で充電が進んでいることを意味する。
1b 突出部
1c 突出孔
1d 活物質層
1e 活性炭の層
Claims (4)
- 正電極と負電極との間にセパレータを介して、捲回または積層してなる電極群に有機電解液を浸透または浸漬させてリチウムイオンの吸蔵・放出を繰返し行なうリチウム二次電池に用いられるリチウム二次電池用電極であって、
前記正電極は、正極集電箔とこの正極集電箔上に形成される正極活物質層とから形成され、前記負電極は、負極集電箔とこの負極集電箔上に形成される負極活物質層とから形成され、この正極および負極活物質がグラフェン相およびアモルファス相から選ばれた少なくとも1つの相を表面層として有する活物質であり、これら正および負極活物質層の表面に活性炭の層が形成されていることを特徴とするリチウム二次電池用電極。 - 前記活性炭の比表面積が1000m2/g以上であることを特徴とする請求項1記載のリチウム二次電池用電極。
- 前記正極集電箔および前記負極集電箔から選ばれる少なくとも1つの集電箔は、該集電箔を貫通し、かつ集電箔の少なくとも一方の箔面側に突出する突出部を有する複数の貫通孔が形成されていることを特徴とする請求項1または請求項2記載のリチウム二次電池用電極。
- 正電極および負電極間にセパレータを介して、捲回または積層してなる電極群に有機電解液を浸透または浸漬させてリチウムイオンの吸蔵・放出を繰返し行なうリチウム二次電池であって、
前記正電極および前記負電極を構成する電極が請求項1、請求項2または請求項3記載のリチウム二次電池用電極であることを特徴とするリチウム二次電池。
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Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH11283623A (ja) * | 1998-03-31 | 1999-10-15 | Sanyo Electric Co Ltd | リチウムイオン電池及びその製造方法 |
JP2001143691A (ja) * | 1999-11-12 | 2001-05-25 | Osaka Gas Co Ltd | 黒鉛系炭素材料、その製造方法、リチウム二次電池用負極材料およびリチウム二次電池 |
JP2001351688A (ja) * | 2000-06-07 | 2001-12-21 | Fdk Corp | 電池・キャパシタ複合素子 |
JP2007280803A (ja) * | 2006-04-07 | 2007-10-25 | Teijin Ltd | ハイブリッド型積層電極、それを用いたハイブリッド二次電源 |
JP2008311171A (ja) * | 2007-06-18 | 2008-12-25 | Sei Kk | リチウム二次電池 |
JP2009070782A (ja) * | 2007-09-18 | 2009-04-02 | Fuji Heavy Ind Ltd | 蓄電デバイス |
JP2011049079A (ja) * | 2009-08-28 | 2011-03-10 | Nissan Motor Co Ltd | 二次電池 |
WO2011049153A1 (ja) | 2009-10-23 | 2011-04-28 | エス・イー・アイ株式会社 | リチウム二次電池およびリチウム二次電池用集電箔の製造方法、ならびにリチウム二次電池用集電箔 |
JP2013030275A (ja) * | 2011-07-26 | 2013-02-07 | Sumitomo Heavy Ind Ltd | 蓄電装置、及び蓄電装置を搭載した作業機械 |
Family Cites Families (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3541913B2 (ja) | 1996-11-27 | 2004-07-14 | 株式会社デンソー | 非水電解液二次電池 |
FR2773267B1 (fr) | 1997-12-30 | 2001-05-04 | Alsthom Cge Alkatel | Supercondensateur a electrolyte non aqueux et a electrode de charbon actif |
CN1167157C (zh) | 1998-05-29 | 2004-09-15 | 松下电器产业株式会社 | 不烧结型电极及其制造方法 |
EP1612819B1 (en) * | 2003-03-31 | 2019-06-12 | Subaru Corporation | Organic electrolyte capacitor |
CN1790799A (zh) * | 2004-12-14 | 2006-06-21 | 中国电子科技集团公司第十八研究所 | 高功率锂离子电池及制备无定形碳包覆正极材料的方法 |
CA2762964C (en) * | 2004-12-16 | 2014-09-16 | Uchicago Argonne, Llc | Long life lithium batteries with stabilized electrodes |
JP5040626B2 (ja) * | 2007-12-07 | 2012-10-03 | 三菱電機株式会社 | 電力貯蔵デバイスセルおよびその制御方法 |
CN101271972B (zh) | 2008-04-30 | 2010-09-01 | 深圳新宙邦科技股份有限公司 | 锂离子电池夹心电极片及其制备方法 |
KR20120042752A (ko) * | 2010-04-28 | 2012-05-03 | 파나소닉 주식회사 | 이차전지 |
CN101807683A (zh) * | 2010-04-28 | 2010-08-18 | 常州市宙纳新能源科技有限公司 | 一种锂离子电容电池的正负极片及其两种极片的制作方法 |
CN102244231A (zh) * | 2010-05-14 | 2011-11-16 | 中国科学院物理研究所 | 对正极活性材料和/或正极进行表面包覆的方法以及正极和电池的制备方法 |
KR101181851B1 (ko) * | 2010-08-09 | 2012-09-11 | 삼성에스디아이 주식회사 | 리튬 이차 전지용 활물질 및 이를 포함하는 리튬 이차 전지 |
KR101138562B1 (ko) | 2010-08-31 | 2012-05-10 | 삼성전기주식회사 | 전극 구조체 및 그 제조 방법, 그리고 상기 전극 구조체를 구비하는 에너지 저장 장치 |
KR101155915B1 (ko) * | 2010-09-13 | 2012-06-20 | 삼성에스디아이 주식회사 | 리튬 이차 전지 |
KR20120056556A (ko) * | 2010-11-25 | 2012-06-04 | 삼성전기주식회사 | 다층 구조의 전극, 및 상기 전극을 포함하는 슈퍼 캐패시터 |
JP5851707B2 (ja) * | 2011-04-01 | 2016-02-03 | 三井造船株式会社 | リン酸鉄リチウム正極材料およびその製造方法 |
-
2012
- 2012-11-09 JP JP2012246967A patent/JP5771810B2/ja not_active Expired - Fee Related
-
2013
- 2013-01-16 WO PCT/JP2013/050674 patent/WO2014073221A1/ja active Application Filing
- 2013-01-16 US US14/441,845 patent/US9660269B2/en not_active Expired - Fee Related
- 2013-01-16 CA CA2888216A patent/CA2888216A1/en not_active Abandoned
- 2013-01-16 CN CN201380053554.1A patent/CN104737333B/zh not_active Expired - Fee Related
- 2013-01-16 EP EP13852725.4A patent/EP2919300A4/en not_active Withdrawn
- 2013-01-16 KR KR1020157014718A patent/KR20150082467A/ko not_active Application Discontinuation
- 2013-05-28 TW TW102118800A patent/TW201419637A/zh unknown
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH11283623A (ja) * | 1998-03-31 | 1999-10-15 | Sanyo Electric Co Ltd | リチウムイオン電池及びその製造方法 |
JP2001143691A (ja) * | 1999-11-12 | 2001-05-25 | Osaka Gas Co Ltd | 黒鉛系炭素材料、その製造方法、リチウム二次電池用負極材料およびリチウム二次電池 |
JP2001351688A (ja) * | 2000-06-07 | 2001-12-21 | Fdk Corp | 電池・キャパシタ複合素子 |
JP2007280803A (ja) * | 2006-04-07 | 2007-10-25 | Teijin Ltd | ハイブリッド型積層電極、それを用いたハイブリッド二次電源 |
JP2008311171A (ja) * | 2007-06-18 | 2008-12-25 | Sei Kk | リチウム二次電池 |
JP2009070782A (ja) * | 2007-09-18 | 2009-04-02 | Fuji Heavy Ind Ltd | 蓄電デバイス |
JP2011049079A (ja) * | 2009-08-28 | 2011-03-10 | Nissan Motor Co Ltd | 二次電池 |
WO2011049153A1 (ja) | 2009-10-23 | 2011-04-28 | エス・イー・アイ株式会社 | リチウム二次電池およびリチウム二次電池用集電箔の製造方法、ならびにリチウム二次電池用集電箔 |
JP2013030275A (ja) * | 2011-07-26 | 2013-02-07 | Sumitomo Heavy Ind Ltd | 蓄電装置、及び蓄電装置を搭載した作業機械 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2919300A4 * |
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