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WO2013052911A1 - Difluorure de polyvinylidène, oxyde de polyéthylène, et particules de matière active modifiées en surface par un dérivé pour utilisé comme liant pour applicationcaoutchouc styrène-butadiènes d'électrode au lithium-ion - Google Patents

Difluorure de polyvinylidène, oxyde de polyéthylène, et particules de matière active modifiées en surface par un dérivé pour utilisé comme liant pour applicationcaoutchouc styrène-butadiènes d'électrode au lithium-ion Download PDF

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Publication number
WO2013052911A1
WO2013052911A1 PCT/US2012/059120 US2012059120W WO2013052911A1 WO 2013052911 A1 WO2013052911 A1 WO 2013052911A1 US 2012059120 W US2012059120 W US 2012059120W WO 2013052911 A1 WO2013052911 A1 WO 2013052911A1
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WO
WIPO (PCT)
Prior art keywords
pvdf
graphite particles
sbr
coated graphite
electrode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2012/059120
Other languages
English (en)
Inventor
Gao Liu
Lei Wang
Park SANG-JAE
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
University of California Berkeley
University of California San Diego UCSD
Original Assignee
University of California Berkeley
University of California San Diego UCSD
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 University of California Berkeley, University of California San Diego UCSD filed Critical University of California Berkeley
Publication of WO2013052911A1 publication Critical patent/WO2013052911A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—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
    • 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
    • H01M4/04—Processes of manufacture in general
    • H01M4/0402—Methods of deposition of the material
    • H01M4/0404—Methods of deposition of the material by coating on electrode collectors
    • 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
    • H01M4/139—Processes of manufacture
    • H01M4/1393—Processes of manufacture of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being polymers
    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/626—Metals
    • 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
    • H01M4/64—Carriers or collectors
    • H01M4/66—Selection of materials
    • H01M4/661—Metal or alloys, e.g. alloy coatings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0025—Organic electrolyte
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • PVDF Polyvinylidene difluoride
  • SBR Water soluble styrene-butadiene rubber
  • Other binders have also been tested.
  • SBR Water soluble styrene-butadiene rubber
  • the reported performance based on non-PVDF binders is lower than the performance for PVDF binder electrodes.
  • FIG. 1 illustrates swelling test of Polyvinylidene difluoride (PVDF) and styrene- butadiene rubber (SBR) in the 1 M LiPF 6 in EC/DEC (1 : 1 by weight) electrolyte according to an embodiment of the invention.
  • PVDF Polyvinylidene difluoride
  • SBR styrene- butadiene rubber
  • Figure 2 illustrates impedance of the swelled PVDF and SBR films after exposing to the electrolyte according to an embodiment of the invention.
  • Figure 3 illustrates the rate performance of electrodes made with PVDF binder and SBR binder according to an embodiment of the invention.
  • Figure 4 illustrates the cycling performance of electrode made with PVDF binder and SBR binder according to an embodiment of the invention.
  • Figure 5 illustrates SEM images of the SBR binder electrodes before and after cycling tests according to an embodiment of the invention.
  • Figure 6 illustrates a graphite particle coated with PVDF polymer layer by a solution based process according to an embodiment of the invention.
  • Figure 7 illustrates a schematic of an electrode cross-section made with PVDF coated graphite particles and SBR binder according to an embodiment of the invention.
  • FIG 8 illustrates rate performance of graphite electrode with different binders.
  • PVDF coating is 2% of the weight of the graphite of the PVDF costing/SBR series (diamond) according to an embodiment of the invention.
  • Figure 9 illustrates cycling performance of PVDF coating graphite with SBR binder according to an embodiment of the invention.
  • FIG 10 illustrates polyethyleneoxide (PEO) derivatives used for active material particle coating according to an embodiment of the invention.
  • PEO polyethyleneoxide
  • Figure 11 illustrates a graphite particle with coated cross-linked PEO polymer layer by the cross-linking process in Figure 10 according to an embodiment of the invention.
  • Figure 12 illustrates a schematic of an electrode cross-section made with PEO coated graphite particles and SBR binder according to an embodiment of the invention.
  • PVDF Polyvinylidene difluoride
  • SBR styrene-butadiene rubber
  • the PVDF binding force is much lower than that of the SBR binder to the lithium ion electrode materials and to current collectors.
  • the swelling of PVDF in an electrolyte solution further compromises the PVDF binding force to the active materials.
  • the SBR swells less than the PVDF in electrolyte solutions as illustrated in Figure 1 .
  • the swelling of the binder due to an electrolyte is an important factor for the lithium ion transport from the electrolyte to the active material particles.
  • the low swelling SBR has a high impedance while the swelled PVDF has a low impedance as evidenced in Figure 2.
  • Embodiments of the invention fully or partially replace PVDF with an SBR binder in the electrode laminates and at the same time retains and/or improves the performance characteristics of the SBR binder electrode in terms of rate, cycle, and storage life.
  • PVDF has been the widely used binder materials for both cathode and anode electrodes.
  • a water soluble SBR binder has also been tested for LiFeP0 4 , LiCo0 2 and Graphite electrodes.
  • Various other binders have also been tested.
  • the only major commercial binder used in lithium ion battery electrodes other than PVDF is the SBR type of binder for graphite anode applications.
  • the reported performance based on non-PVDF binders is lower than the performance for the PVDF binder electrodes.
  • various embodiments of the invention describe the benefits of using a PVDF/SBR hybrid binder electrode system.
  • the commercially used SBR is a SBR aqueous suspension.
  • SBR solid 50-100 nm round particles are suspended in a water solution.
  • the SBR water suspension is made by an emulsion polymerization process.
  • Surfactant molecules cover the surface of SBR particles.
  • the surfactant produces the suspension properties of SBR nanometer (nm) sized balls in the water solution.
  • the SBR nm particles provide the adhesion between the solid lithium-ion storage and conductive additive particles.
  • increasing the amount of SBR binder degrades the performance of the graphite electrode based on the SBR binder.
  • An embodiment of the invention demonstrates that when SBR is dissolved in a toluene organic solvent, and the SBR/toluene solution is used to make graphite and acetylene black additive electrodes, the rate and cycling performance of the SBR based electrode is less than hoped for (see Figure 3, 4). Also, SBR delamination was detected after the cell was cycled (see Figure 5).
  • SBR is made in commodity scale at very low cost as compared to PVDF.
  • slurry made with low boiling point organic solvents can significantly decrease the energy used and shorten the time to dry the laminate.
  • lithium is stable in hydrocarbon solvents such as toluene, allowing for the inclusion of a stabilized lithium metal powder (SLMP) into the slurry mixing, coating and drying process.
  • SLMP stabilized lithium metal powder
  • this SLMP added electrode can reduce irreversible lithium loss during the formation; 2) allows for lithium ion battery formation without application of an external charge; 3) if a large amount of SLMP is added to the anode, it will prelithiate the anode to enable the use of none lithium containing low cost cathodes, such as CFx and Mn0 2 (electrolytic manganese dioxide) in rechargeable cells.
  • CFx and Mn0 2 electrolytic manganese dioxide
  • Various embodiments of this invention contemplate the use of SBR binder for both cathode and anode lithium ion electrodes.
  • graphite material is utilized as for the anode.
  • Lithium-ion battery electrode binders other than PVDF have not been widely accepted due to the reduced performance. Both rate and lifetime have been compromised compared to the electrodes made with PVDF based binder.
  • the binding force of PVDF is not as strong as many of the other binders such as SBR.
  • Various embodiments of the invention combine both the superior performance of the PVDF binder and the strong binding force of the SBR binder to form an electrode system that has increased or at least equivalent performance compared to the PVDF binder based electrode.
  • the improved SBR/PVDF based electrode will use far less PVDF binder relative to the PVDF only electrode to reduce the cost of the PVDF materials.
  • various embodiments of the invention provide a new way to achieve comparable or improved results at a reduced cost.
  • PVDF polystyrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-styrene-sulfate (PS) solvent) to form a PVDF/NMP solution. A certain amount of graphite particles is added to the solution and mixed thoroughly. The NMP will be evaporated to leave PVDF coated graphite particles. The PVDF coated graphite particle ranges from 10-0.0001% by weight to the graphite. The current result shows that from 0.75-3% of PVDF coating. A 1% PVDF coating by weight gives the best performance data.
  • NMP N-methylpyrrolidone
  • the PVDF coated graphite particles are mixed with SBR binder in either a water soluble format or SBR in organic solvent such as toluene to form a slurry.
  • organic solvent such as toluene
  • Acetylene black and/or carbon fiber can be part of a conductive additive to add into the slurry.
  • the organic solvent should not dissolve the PVDF coating.
  • a toluene solvent may be used.
  • the slurry may then be utilized to coat an electrode laminate on a Cu current collector, and dried to form a negative electrode as shown in Figure 7.
  • the SBR and PVDF do not mix, and PVDF does not dissolve in toluene.
  • the PVDF remains on the surface of the graphite.
  • the SBR is also phase separated from the PVDF in a micro-scale, when the electrode is made.
  • the PVDF will uptake electrolyte and swell.
  • This swelled PVDF layer is in connection with the active material particle surface.
  • the electrolyte swelled PVDF provides a channel for the lithium-ions to move between the electrolyte and active material surface.
  • This invention will overcome the lithium-ion blocking effect exerted by a SBR coating on active material surface in SBR only systems.
  • FIG. 8 shows the rate performance comparison among the three electrode compositions: 1) PVDF binder (orange square), 2) SBR binder (blue triangle) and 3) PVDF coating/SBR binder (diamond).
  • the rate performance of 2% PVDF coated graphite performs as good as a PVDF binder based electrode, and far superior than the SBR binder without PVDF coating.
  • the electrode made with PVDF coating graphite and SBR binder shows very good cycling performance as illustrated in Figure 9.
  • Possible surface modification agents for an anode include PVDF and related copolymer, polyether (such as polyethyleneoxide (PEO)) type of materials, polyvinylenecarbonate and its derivatives.
  • Possible surface modification agents for cathode include PVDF
  • Figure 10 shows the molecular structures of the PEO derivatives according to
  • a thin layer of PEO type of polymer precursors (lc or 2c) is coated on the surface of graphite particles as shown in Figure 11.
  • An example of the process is as follows.
  • the lc polymer precursor ( Figure 10) and a small amount of radical initiator e.g. Azobisisobutyronitrile, (AIBN)
  • AIBN Azobisisobutyronitrile
  • the lc polymer precursor/graphite mixture is dispersed in a solvent, which does not dissolve thelc polymer precursor, (eg. Hexane). Heating or UV light will be used to initiate the crosslinking of the lc polymer precursor to form a permanent coating (Id) on the surface of the graphite, while the coated graphite particles are dispersed in the solvent.
  • a solvent which does not dissolve thelc polymer precursor, (eg. Hexane).
  • Heating or UV light will be used to initiate the crosslinking of the lc polymer precursor to form a permanent coating (Id) on the surface of the graphite, while the coated graphite particles are dispersed in the solvent.
  • This Id coated graphite particles will be mixed with SBR binder in aqueous based SBR dispersion or SBR in organic solvent such as toluene to form slurry.
  • Acetylene black or/and carbon fiber can be part of the conductive additive to add into the slurry.
  • the solvents used in this step should not dissolve the lc coating, as it is already crosslinked.
  • This slurry is used to coat an electrode laminate on a Cu current collector, and dried to form the negative electrode as Figure 12.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

Les liants d'électrode pour batterie au lithium-ion autres que le PVDF ne sont pas largement accueillis en raison de leur rendement limité. Tant la teneur que la durée de vie d'autres liants ont été compromises par rapport à une électrode réalisée avec un liant dont le PVDF est le seul constituant. La force d'adhérence du PVDF n'est toutefois pas aussi importante que celle d'une sélection d'autres liants tels que le SBR. Un mode de réalisation de l'invention allie le rendement supérieur du liant PVDF et la grande force d'adhérence du liant SBR pour former un système d'électrodes à rendement meilleur ou au moins équivalent par rapport à des électrodes dont le PVDF est le seul constituant Cette électrode améliorée utilisera moins de liant PVDF, ce qui réduit le coût des matériaux PVDF. Cette invention offre ainsi une nouvelle façon d'obtenir des résultats meilleurs ou équivalents à un coût beaucoup plus bas.
PCT/US2012/059120 2011-10-05 2012-10-05 Difluorure de polyvinylidène, oxyde de polyéthylène, et particules de matière active modifiées en surface par un dérivé pour utilisé comme liant pour applicationcaoutchouc styrène-butadiènes d'électrode au lithium-ion Ceased WO2013052911A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201161543629P 2011-10-05 2011-10-05
US61/543,629 2011-10-05

Publications (1)

Publication Number Publication Date
WO2013052911A1 true WO2013052911A1 (fr) 2013-04-11

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106463803A (zh) * 2014-05-15 2017-02-22 宝马股份公司 锂空气电池组
WO2018174565A1 (fr) * 2017-03-22 2018-09-27 주식회사 엘지화학 Électrode pour batterie entièrement solide et son procédé de fabrication
CN115353476A (zh) * 2022-08-19 2022-11-18 安阳工学院 一种马来酰亚胺-酰胺-低聚乙二醇-丙酸的合成方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080274408A1 (en) * 2004-06-24 2008-11-06 Christine Ruth Jarvis Anode for Lithium Ion Cell
US20090123850A1 (en) * 2005-07-04 2009-05-14 Showa Denko K.K. Method for producing anode for lithium secondary battery and anode composition, and lithium secondary battery
US20100129719A1 (en) * 2008-11-26 2010-05-27 Sony Corporation Nonaqueous electrolyte secondary battery

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080274408A1 (en) * 2004-06-24 2008-11-06 Christine Ruth Jarvis Anode for Lithium Ion Cell
US20090123850A1 (en) * 2005-07-04 2009-05-14 Showa Denko K.K. Method for producing anode for lithium secondary battery and anode composition, and lithium secondary battery
US20100129719A1 (en) * 2008-11-26 2010-05-27 Sony Corporation Nonaqueous electrolyte secondary battery

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106463803A (zh) * 2014-05-15 2017-02-22 宝马股份公司 锂空气电池组
US10693204B2 (en) 2014-05-15 2020-06-23 Bayerische Motoren Werke Aktiengesellschaft Lithium-air battery
WO2018174565A1 (fr) * 2017-03-22 2018-09-27 주식회사 엘지화학 Électrode pour batterie entièrement solide et son procédé de fabrication
US11631839B2 (en) 2017-03-22 2023-04-18 Lg Energy Solution, Ltd. Electrode for solid state battery and method for manufacturing the same
CN115353476A (zh) * 2022-08-19 2022-11-18 安阳工学院 一种马来酰亚胺-酰胺-低聚乙二醇-丙酸的合成方法
CN115353476B (zh) * 2022-08-19 2024-03-26 安阳工学院 一种马来酰亚胺-酰胺-低聚乙二醇-丙酸的合成方法

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