WO2023032592A1 - 非水電解質二次電池用の負極活物質、それを用いた非水電解質二次電池、および非水電解質二次電池用の負極活物質の製造方法 - Google Patents

非水電解質二次電池用の負極活物質、それを用いた非水電解質二次電池、および非水電解質二次電池用の負極活物質の製造方法 Download PDF

Info

Publication number
WO2023032592A1
WO2023032592A1 PCT/JP2022/030083 JP2022030083W WO2023032592A1 WO 2023032592 A1 WO2023032592 A1 WO 2023032592A1 JP 2022030083 W JP2022030083 W JP 2022030083W WO 2023032592 A1 WO2023032592 A1 WO 2023032592A1
Authority
WO
WIPO (PCT)
Prior art keywords
group
active material
negative electrode
less
integer
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/JP2022/030083
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
翔 柴田
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.)
Panasonic Intellectual Property Management Co Ltd
Original Assignee
Panasonic Intellectual Property Management Co 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 Panasonic Intellectual Property Management Co Ltd filed Critical Panasonic Intellectual Property Management Co Ltd
Priority to EP22864178.3A priority Critical patent/EP4398343A4/en
Priority to US18/686,553 priority patent/US20240356026A1/en
Priority to CN202280058243.3A priority patent/CN117897831A/zh
Priority to JP2023545388A priority patent/JPWO2023032592A1/ja
Publication of WO2023032592A1 publication Critical patent/WO2023032592A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00—Silicon; Compounds thereof
    • C01B33/20—Silicates
    • C01B33/32—Alkali metal silicates
    • 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
    • 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
    • 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
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • 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
    • 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
    • H01M4/625—Carbon or graphite
    • 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
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • 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
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • 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

  • the present disclosure relates to a negative electrode active material for non-aqueous electrolyte secondary batteries, a non-aqueous electrolyte secondary battery using the same, and a method for manufacturing the negative electrode active material for non-aqueous electrolyte secondary batteries.
  • Silicon materials such as silicon (Si) and silicon oxide represented by SiOx are known to be able to absorb more lithium ions per unit volume than carbon materials such as graphite, and are used as negative electrodes of lithium ion batteries and the like. is being considered for application to A non-aqueous electrolyte secondary battery using a silicon material as a negative electrode active material has a problem of lower charge/discharge efficiency than a case where graphite is used as a negative electrode active material. Therefore, it has been proposed to use lithium silicate as a negative electrode active material in order to improve charge/discharge efficiency.
  • Patent Document 1 Japanese Unexamined Patent Application Publication No. 2003-160328 describes "a lithium-containing silicon oxide powder represented by the general formula SiLi x O y , wherein the range of x and y is 0 ⁇ x ⁇ 1.0,0 ⁇ A lithium-containing silicon oxide powder characterized in that y ⁇ 1.5, and in which lithium is coalesced and partially crystallized.”
  • Patent Document 2 Japanese Patent Application Laid-Open No. 2014-150068 discloses that "a silicon-containing substance having a surface water content per unit specific surface area (200-300°C) of 0.1 to 20 ppm/(m 2 /g) is added to silane.
  • Non-Patent Document 1 reports that adding a vinyl group-containing silane coupling agent to the electrolyte of a monopolar battery using a Si/C composite improves the capacity retention rate in charge-discharge cycles.
  • one of the objects of the present disclosure is to provide a negative electrode active material that can constitute a non-aqueous electrolyte secondary battery having a high capacity retention rate in charge-discharge cycles.
  • the negative electrode active material includes active material particles containing silicon and a surface layer formed on the surface of the active material particles, and the surface layer is a reaction product of a compound reacted to form a siloxane bond.
  • the compound comprises a structure represented by Si-R1-Si, wherein R1 is a hydrocarbon group having a carbon number in the range of 1 to 50, and one of the two Si is carbon A group represented by -O-(C x1 H 2x1+1 O y1 ) including an alkoxy group and an oxyalkylene group whose number is in the range of 1 to 6 (x1 is an integer of 2 or more and 6 or less and y1 is 1 or more and 3 or less is an integer), a chloro group, and at least one atomic group selected from the group consisting of a hydroxyl group, and the other of the two Si is an alkoxy group having a carbon number in the range of 1 to 6 , a group represented by -O-(C x2 H 2x2+1 O y2 ) containing an oxyalkylene group (x2 is an integer of 2 or more and 6 or less and y2 is an integer of 1 or more and 3 or less), a chloro group, and a
  • the nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a nonaqueous electrolyte, and the negative electrode includes the negative electrode active material according to the present disclosure.
  • Another aspect of the present disclosure relates to a method for producing a negative electrode active material for non-aqueous electrolyte secondary batteries.
  • the manufacturing method includes a first step of contacting a compound or a liquid in which the compound is dissolved with silicon-containing active material particles, and the compound or the liquid and the active material particles are in contact.
  • a second step of reacting the compound to form a siloxane bond in the state of and one of the two Si includes an alkoxy group and an oxyalkylene group having a carbon number in the range of 1 to 6, and is represented by -O-(C x1 H 2x1+1 O y1 ) (x1 is an integer of 2 or more and 6 or less and y1 is an integer of 1 or more and 3 or less), a chloro group, and at least one atomic group selected from the group consisting of a hydroxyl group is bonded, and
  • the other of the two Si is a group represented by -O-(C x2 H 2x2+1 O y2 ) containing an alkoxy group and an oxyalkylene group having a carbon number in the range of 1 to 6 (x2 is 2 or more and 6 or less is an integer and y2 is an integer of 1 or more and 3 or less), a chloro group, and a hydroxyl group.
  • FIG. 1 is a partially cutaway plan view schematically showing the structure of a non-aqueous electrolyte secondary battery according to an embodiment of the present invention
  • FIG. 2 is a cross-sectional view of the non-aqueous secondary battery shown in FIG. 1 taken along the line X-X';
  • FIG. 1 is a partially cutaway plan view schematically showing the structure of a non-aqueous electrolyte secondary battery according to an embodiment of the present invention
  • FIG. 2 is a cross-sectional view of the non-aqueous secondary battery shown in FIG. 1 taken along the line X-X';
  • a negative electrode active material for a non-aqueous electrolyte secondary battery includes silicon-containing active material particles and a surface layer formed on the surfaces of the active material particles.
  • the negative electrode active material and the surface layer are hereinafter sometimes referred to as “negative electrode active material (N)" and “surface layer (L)".
  • the surface layer (L) contains a reaction product of a given compound reacting to form a siloxane bond.
  • the compound may be hereinafter referred to as "compound (1)”.
  • Compound (1) contains a structure represented by Si--R1--Si.
  • R1 is a hydrocarbon group having 1 to 50 carbon atoms.
  • One of the two Si is a group represented by -O-(C x1 H 2x1+1 O y1 ) containing an alkoxy group or an oxyalkylene group having a carbon number in the range of 1 to 6 (x1 is 2 or more and 6 or less is an integer and y1 is an integer of 1 or more and 3 or less), a chloro group, and a hydroxyl group.
  • the other of the two Si is a group represented by -O-(C x2 H 2x2+1 O y2 ) containing an alkoxy group and an oxyalkylene group having a carbon number in the range of 1 to 6 (x2 is 2 or more and 6 or less is an integer and y2 is an integer of 1 or more and 3 or less), a chloro group, and a hydroxyl group.
  • An oxyalkylene group is a group represented by —O—C x H 2x —.
  • the oxyalkylene group of oxygen atoms are bonded to Si.
  • -O-(C x H 2x+1 O y ) including an oxyalkylene group containing an oxygen atom bonded to Si (where x is an integer of 2 or more and 6 or less, and y is 1 or more and 3 or less is an integer) is sometimes referred to as an "oxyalkyl group”.
  • y eg, y1, y2, y6 described later
  • y may be 1 or 2.
  • Examples of the oxyalkyl group include a group represented by -OC x4 H 2x4 -OC x5 H 2x5+1 (x4 is an integer of 1 or more and 3 or less, and x5 is an integer of 1 or more and 3 or less), Examples include -OCH 2 CH 2 OCH 3 and the like.
  • the compound (1) may be a compound represented by the following formula (1).
  • At least one selected from the group consisting of R2, R3, and R4 each independently includes an alkoxy group having a carbon number of 1 to 6, an oxyalkylene group, and -O-( C x1 H 2x1+1 O y1 ) (x1 is an integer of 2 or more and 6 or less and y1 is an integer of 1 or more and 3 or less), a chloro group, or a hydroxyl group.
  • At least one selected from the group consisting of R5, R6, and R7 each independently includes an alkoxy group and an oxyalkylene group having 1 to 6 carbon atoms, and -O-(C x2 H 2x2+1 O y2 ) (x2 is an integer of 2 or more and 6 or less and y2 is an integer of 1 or more and 3 or less), a chloro group, or a hydroxyl group.
  • R2 to R7 are each independently a hydrocarbon group having a carbon number in the range of 1 to 6, a hydrogen atom, or a group represented by C x3 H 2x3+y3+1 N y3 O z3 S w3 (x3 is 1 or more and 6 or less y3 is an integer of 0 or more and 3 or less, z3 is an integer of 0 or more and 3 or less, w3 is an integer of 0 or more and 3 or less, and 1 ⁇ y3+z3+w3).
  • R2 to R7 may be the same or different.
  • hydrocarbon groups contained in R2 to R7 include hydrocarbon groups having 1 to 6 carbon atoms, such as alkyl groups, alkenyl groups having 1 to 6 carbon atoms, and alkynyl groups.
  • the group represented by C x3 H 2x3+y3+1 N y3 O z3 S w3 is not an alkoxy group having 1 to 6 carbon atoms and is represented by —O—(C x1 H 2x1+1 O y1 ). is not based on y3, Z3, and w3 may each independently be an integer of 0-2 or an integer of 0-1.
  • the sum of y3, z3, and w3 may be in the range of 1-3, or in the range of 1-2.
  • the sum of y3, z3, and w3 may be 1 or 2, and is 1 in one example.
  • Examples of the group represented by C x3 H 2x3+y3+1 N y3 O z3 S w3 include a group represented by C x3 H 2x3+1 O y3 , an alkylamino group having 1 to 6 carbon atoms, and is in the range of 1 to 6, and the like.
  • the group represented by C x3 H 2x3+1 O y3 is bonded to Si via a carbon atom, for example.
  • Examples of groups represented by C x3 H 2x3+1 O y3 include hydroxyalkyl groups.
  • the rest of R2 to R7 may each independently be a hydrocarbon group having a carbon number in the range of 1 to 6, or a hydrogen atom.
  • the alkoxy group having a carbon number in the range of 1 to 6 and the oxyalkylene group described above are collectively referred to as "-O-( C x6 H 2x6+1 O y6 ) (x6 is an integer of 2 or more and 6 or less, and y6 is an integer of 0 or more and 3 or less)".
  • an alkoxy group having 1 to 6 carbon atoms and the oxyalkylene group described above may be collectively read as "a group containing an alkoxy group and having 1 to 6 carbon atoms".
  • the surface layer formed on the surface of the active material particles contains a reaction product of compound (0) reacting to form a siloxane bond.
  • Compound (0) is a compound containing two silicon atoms bonded with an atomic group capable of forming a siloxane bond by reaction and R1 connecting the two silicon atoms.
  • the number of such atomic groups bonded to one silicon atom is in the range of 1 to 3, preferably 2, more preferably 3.
  • Examples of atomic groups capable of forming siloxane bonds by reaction include alkoxy groups, hydroxyl groups, chloro groups, and the oxyalkyl groups described above.
  • an alkoxy group, a hydroxyl group, a chloro group, and the above-mentioned oxyalkyl group having 1 to 6 carbon atoms may be collectively referred to as "atomic group (G)".
  • a reaction for example, a hydrolysis/condensation reaction in which a compound having an alkoxysilyl group is reacted to form a siloxane bond is widely known.
  • R1 exemplified for compound (1) can be applied to R1 in compound (0).
  • Examples of compound (0) include at least part of examples of compound (1).
  • compound (0) and compound (1) Commercially available compounds may be used as compound (0) and compound (1). Moreover, a compound whose synthesis method is known may be synthesized by a known synthesis method.
  • the surface of the active material particles is protected by the reaction product of compound (1). At least part of compound (1) forms a siloxane bond with silicon in the active material particles. In compound (1), silyl groups forming siloxane bonds are linked by R1. Therefore, the surface of the active material particles is protected by forming a siloxane bond between the two silyl groups and the silicon of the active material particles. Since the reaction product of compound (1) contains the R1 portion, it flexibly follows the expansion and contraction of the active material particles due to charge and discharge, and the surface is protected even if the active material particles repeatedly expand and contract due to charge and discharge cycles. Layers are hard to break. Therefore, according to the present disclosure, it is possible to suppress side reactions with components in the electrolytic solution on the surfaces of the active material particles. As a result, according to the present disclosure, it is possible to increase the capacity retention rate in charge/discharge cycles.
  • those that are not the atomic group (G) described above may each independently be the groups described above.
  • those that are not the above-described atomic group (G) are each independently a hydrocarbon group having a carbon number in the range of 1 to 6, a hydrogen atom, or the above formula C It may be a group represented by x3H2x3 +y3+1Ny3Oz3Sw3 .
  • Formula (1) preferably satisfies the following conditions (V1) or (V2), and more preferably satisfies the following conditions (V3) or (V4).
  • Formula (1) may satisfy the following condition (V5) or (V6).
  • V1 The number of carbon atoms contained in each of R2 to R7 is 4 or less.
  • V2 at least two selected from the group consisting of R2, R3, and R4 are alkoxy groups having 1 to 4 carbon atoms, and at least two selected from the group consisting of R5, R6, and R7; is an alkoxy group having 1 to 4 carbon atoms.
  • R2 to R7 those that are not alkoxy groups having 1 to 4 carbon atoms are hydrocarbon groups having 1 to 6 carbon atoms (alkyl groups, alkenyl groups, alkynyl groups), or hydrogen atoms is.
  • All of R2 to R7 are alkoxy groups having 1 to 4 carbon atoms (for example, 1 to 3 carbon atoms).
  • All of R2 to R7 are each independently a methoxy group or an ethoxy group.
  • R2-R7 may be methoxy or ethoxy groups.
  • all of R2 to R7 may be methoxy groups, or all of R2 to R7 may be ethoxy groups.
  • the number of carbon atoms in R1 is 1 or more, and may be 2 or more, 3 or more, 4 or more, or 6 or more.
  • the carbon number of R1 is 50 or less, and may be 30 or less, 20 or less, 10 or less, 8 or less, or 6 or less.
  • the number of carbon atoms in R1 may range from 1 to 30, from 1 to 20, from 1 to 10, from 1 to 6.
  • the lower limit may be 2 or more, 3 or more, 4 or more, or 6 or more as long as the lower limit is not greater than or equal to the upper limit.
  • Two Si atoms in compound (1) may be linked by a carbon chain having 1 to 20 carbon atoms. That is, compound (1) contains a chain structure represented by Si(—C) n —Si, where n may be in the range of 1-20.
  • the carbon number n of the carbon chain is 1 or more, and may be 2 or more, 3 or more, or 4 or more.
  • the carbon number is 20 or less, and may be 10 or less, 8 or less, or 6 or less.
  • the carbon number n may range from 1-20, 1-10, 1-8, or 1-6. In these ranges, the lower limit may be 2 or more, 3 or more, or 6 or more as long as the lower limit is not greater than or equal to the upper limit.
  • R1 may be a saturated hydrocarbon group or an unsaturated hydrocarbon group.
  • R1 may include or be at least one selected from the group consisting of a vinylene group, an ethynylene group, and a phenylene group.
  • R1 may include at least one selected from the group consisting of a vinylene group, an ethynylene group, and a phenylene group and an alkylene group, or may be composed only of the at least one group and an alkylene group.
  • R1 may be an alkylene group to which a branched chain may be attached, or may be a linear alkylene group.
  • the number of carbon atoms in these alkylene groups may be within the range exemplified for the number n of carbon atoms in the carbon chain.
  • a linear alkylene group may be represented by -(CH 2 ) n - (where n is the number of carbon atoms, n as described above).
  • a coating composed of a reaction product can be formed on the surface of the active material particles.
  • the coating may be hereinafter referred to as an "SRS coating".
  • SRS coating The greater the number of carbon atoms in the carbon chain connecting two Sis, the more flexible the SRS film becomes, facilitating reversible deformation. However, if the number of carbon atoms is excessively large, the carbon chain becomes too long, the denseness of the SRS coating is reduced, and the effect of suppressing side reactions is reduced. Therefore, the number of carbon atoms n is preferably in the range of 1-6, more preferably in the range of 2-4.
  • a preferred example of compound (1) is bis(alkoxysilyl)alkane.
  • a preferred example of bis(alkoxysilyl)alkane is bis(alkoxysilyl)C 1-6 alkane, which may be bis(alkoxysilyl)C 2-4 alkane.
  • the SRS coating formed when bis(alkoxysilyl)alkane is used is composed of a stable siloxane structure and an alkylene group. Such an SRS coating is not only easily elastically deformable, but also chemically and structurally stable.
  • bis(alkoxysilyl)alkanes at least one selected from the group consisting of 1,2-bis(trialkoxysilyl)ethane and 1,6-bis(trialkoxysilyl)hexane is easily available.
  • 1,2-bis(trialkoxysilyl)ethane includes 1,2-bis(trimethoxysilyl)ethane, 1,2-bis(triethoxysilyl)ethane and the like.
  • 1,6-bis(trialkoxysilyl)hexane includes 1,6-bis(trimethoxysilyl)hexane, 1,6-bis(triethoxysilyl)hexane and the like.
  • G atomic groups
  • the mass of the reaction product of compound (1) contained in the surface layer may be in the range of 0.001% to 10% (for example, in the range of 0.05% to 1%) of the mass of the active material particles. This percentage may be analyzed, such as by ICP analysis.
  • the reaction product may have a chemical structure in which Si in the Si-R1-Si structure is bonded to Si (silicon) in the active material particles through siloxane bonds. That is, the surface layer (L) includes a chemical structure (reaction product of compound (1)) in which Si in a plurality of Si-R1-Si structures is bonded to Si in the active material particles through siloxane bonds. It's okay.
  • the reaction product may have a structure in which Si in a plurality of Si--R1--Si structures are bonded to each other and to Si in the active material particles through siloxane bonds.
  • the surface layer (L) has a chemical structure in which Si in a plurality of Si-R1-Si structures are bonded to each other and to Si in the active material particles by siloxane bonds (reaction product of compound (1) ) may be included.
  • the atomic group (G) contained in R2 to R4 and R5 to R7 is capable of forming an X—O—Si—R bond with the surface of the material containing the silicon element, and the surface of the material containing the silicon element is , can be capped with a Si--R1--Si structure with stable siloxane bonds at both ends. That is, the surface of the material containing elemental silicon can be covered with a film containing the Si--R1--Si structure.
  • the surface layer (L) of the negative electrode active material (N) may contain conductive carbon.
  • formula (1) preferably satisfies the above condition (V2) or (V5). Since active materials containing silicon have low electrical conductivity, capacity is likely to decrease during charge-discharge cycles. By arranging conductive carbon on the surface of the active material, it is possible to suppress a decrease in capacity during charge-discharge cycles. However, simply arranging the conductive carbon on the surface reduces the adhesion between the active material and the conductive carbon due to the expansion and contraction of the active material during charge/discharge cycles, and the conductivity between them decreases.
  • the surface layer (L) contains the reaction product of compound (1) and conductive carbon
  • the charge/discharge efficiency of the silicon-containing negative electrode active material can be greatly improved. This may be because the network formed by the reaction product of compound (1) maintains the adhesion between the active material and the conductive carbon.
  • Examples of conductive carbon include amorphous carbon, graphite, graphitizable carbon (soft carbon), and non-graphitizable carbon (hard carbon). Among them, amorphous carbon is preferable because it facilitates formation of a thin conductive layer covering the surface of the composite particles. Examples of amorphous carbon include carbon black, burned pitch, coke, and activated carbon.
  • Graphite includes natural graphite, artificial graphite, graphitized mesophase carbon, and the like.
  • the compound (1) is thought to permeate the gaps between the conductive carbon particles and bond with Si in the negative electrode active material particles.
  • the active material particles contain silicon (silicon element).
  • a material containing silicon is sometimes treated as a kind of alloy-based material.
  • the alloy-based material refers to a material containing an element capable of forming an alloy with lithium.
  • Elements capable of forming an alloy with lithium include silicon and tin, and silicon (Si) is particularly promising.
  • the manufacturing method of the active material particles Active material particles may be produced by a known method, or commercially available ones may be used.
  • Materials containing silicon may be silicon alloys, silicon compounds, or composite materials. Among them, a composite material containing a lithium ion conductive phase and silicon particles dispersed in the lithium ion conductive phase is promising.
  • the lithium ion conductive phase for example, a silicon oxide phase, a silicate phase, a carbon phase, or the like can be used.
  • the silicon oxide phase is a material with relatively high irreversible capacity.
  • the silicate phase is preferable because of its low irreversible capacity.
  • a major component (eg, 95-100% by weight) of the silicon oxide phase may be silicon dioxide.
  • the composition of a composite material comprising a silicon oxide phase and silicon particles dispersed therein can collectively be expressed as SiO x .
  • SiOx has a structure in which silicon fine particles are dispersed in amorphous SiO 2 .
  • the content ratio x of oxygen to silicon is, for example, 0.5 ⁇ x ⁇ 2.0, more preferably 0.8 ⁇ x ⁇ 1.5.
  • the silicate phase may contain, for example, at least one selected from the group consisting of Group 1 elements and Group 2 elements of the long period periodic table.
  • Group 1 elements of the long period periodic table and Group 2 elements of the long period periodic table include lithium (Li), potassium (K), sodium (Na), magnesium (Mg), and calcium (Ca). , strontium (Sr), barium (Ba), and the like.
  • Other elements may include aluminum (Al), boron (B), lanthanum (La), phosphorus (P), zirconium (Zr), titanium (Ti), and the like.
  • a silicate phase containing lithium hereinafter also referred to as a lithium silicate phase
  • a silicate phase containing lithium is preferable because of its small irreversible capacity and high initial charge/discharge efficiency.
  • the lithium silicate phase may be an oxide phase containing lithium (Li), silicon (Si), and oxygen (O), and may contain other elements.
  • the atomic ratio of O to Si: O/Si in the lithium silicate phase is greater than 2 and less than 4, for example.
  • O/Si is greater than 2 and less than 3.
  • the atomic ratio of Li to Si in the lithium silicate phase: Li/Si is greater than 0 and less than 4, for example.
  • Elements other than Li, Si and O that can be contained in the lithium silicate phase include, for example, iron (Fe), chromium (Cr), nickel (Ni), manganese (Mn), copper (Cu), molybdenum (Mo), Examples include zinc (Zn) and aluminum (Al).
  • the carbon phase can be composed of, for example, amorphous carbon with low crystallinity (that is, amorphous carbon).
  • Amorphous carbon may be, for example, hard carbon, soft carbon, or otherwise.
  • Each of the active material particles (N) and the negative electrode mixture layer may contain a material that electrochemically absorbs and releases lithium ions, lithium metal, a lithium alloy, etc., in addition to the material containing the silicon element.
  • a carbon material is preferable as the material for electrochemically intercalating and deintercalating lithium ions.
  • Examples of carbon materials include graphite, graphitizable carbon (soft carbon), and non-graphitizable carbon (hard carbon). Among them, graphite is preferable because it has excellent charging/discharging stability and low irreversible capacity.
  • the active material particles are composite particles containing a lithium silicate phase represented by Li x SiO y (0 ⁇ x ⁇ 4, 0 ⁇ y ⁇ 4) and a silicon phase dispersed in the lithium silicate phase.
  • x and y are independent of x and y for compound (1).
  • Such composite particles may be produced, for example, by the method described in Examples, or may be produced by a known method.
  • the crystallite size of the silicon phase may be in the range of 1 nm to 1000 nm (eg, in the range of 200 nm to 500 nm).
  • the crystallite size of the silicon phase is calculated by Scherrer's formula from the half width of the diffraction peak attributed to the (111) plane of the silicon phase (simple elemental Si) in the X-ray diffraction pattern.
  • the active material particles may be composite particles containing a carbon phase and a silicon phase dispersed within the carbon phase.
  • the carbon phase can, for example, consist of amorphous carbon (ie, amorphous carbon).
  • Amorphous carbon may be, for example, hard carbon, soft carbon, or others.
  • Amorphous carbon generally refers to a carbon material having an average interplanar spacing d002 of (002) planes exceeding 0.34 nm as measured by an X-ray diffraction method.
  • a production method according to the present disclosure is a method for producing a negative electrode active material (N) for a non-aqueous electrolyte secondary battery according to the present disclosure.
  • the negative electrode active material (N) may be produced by a method other than the method described below. Since the items described with respect to the negative electrode active material (N) can be applied to the following manufacturing method, redundant description may be omitted. Matters described in the manufacturing method below may be applied to the negative electrode active material according to the present disclosure.
  • This manufacturing method includes a first step and a second step. Included in this order.
  • the first and second steps are carried out under conditions in which compound (1) forms a siloxane bond.
  • the first and second steps may be carried out under the same conditions as those for hydrolyzing and condensing a known alkoxysilyl group-containing silane coupling agent to form a siloxane bond.
  • the first step is to bring the compound (1) or a liquid in which the compound (1) is dissolved into contact with active material particles containing silicon.
  • the liquid may be hereinafter referred to as “liquid (S)”.
  • the first step may be a step of dispersing silicon-containing active material particles in compound (1) or liquid (S).
  • the first step may be a step of applying compound (1) or liquid (S) to the surface of the silicon-containing active material particles.
  • the compound (1) is the compound described above, and the compound represented by formula (1) can be used.
  • the active material particles are the active material particles described above.
  • Liquid (S) can be prepared by dissolving compound (1) in a solvent. A part of the compound (1) may react to form a siloxane bond before the second step is performed.
  • Solvents may include lower alcohols (eg, ethanol), water, and acids. Examples of acids include hydrochloric acid and the like.
  • the content of the reaction product of compound (1) in the negative electrode active material (N) can be changed by changing the concentration of compound (1) in liquid (S).
  • the concentration of compound (1) in liquid (S) may be in the range of 0.0001 to 10 mol/liter (eg, in the range of 0.001 to 0.1 mol/liter).
  • the mass of the compound (1) per 1 g mass of the active material particles dispersed in the liquid (S) may be in the range of 0.0001 to 1 g (for example, in the range of 0.001 to 0.1 g).
  • the second step is a step of reacting compound (1) to form a siloxane bond while the compound (1) or liquid (S) is in contact with the active material particles.
  • the second step may be performed, for example, by maintaining the temperature of the liquid (S) and the active material particles at a predetermined temperature for a predetermined period of time.
  • the liquid (S) may be stirred in the second step.
  • the predetermined temperature may be in the range of 10-200° C. (eg, in the range of 40-100° C.).
  • the predetermined time may be in the range of 1-120 hours (eg, in the range of 12-72 hours).
  • a negative electrode active material (N) is obtained by the second step.
  • the negative electrode active material (N) obtained in the second step may be washed and/or dried as necessary.
  • the production method according to the present disclosure includes a step of placing conductive carbon on the surface of the active material particles before the first step, between the first step and the second step, or after the second step. (a) may be included. By performing the step (a), the surface layer (L) containing the reaction product of the compound (1) and the conductive carbon can be formed.
  • the step (a) may be performed by heat-treating a mixture of the active material particles and the conductive carbon.
  • raw materials for the conductive carbon for example, coal pitch, coal tar pitch, petroleum pitch, phenol resin, or the like can be used.
  • the heat treatment may be performed, for example, by heating at a temperature of 450-1000° C. for 1-10 hours.
  • the conductive carbon described above can be used as the conductive carbon.
  • step (a) may form the conductive carbon layer by reacting a hydrocarbon gas on the surface of the composite particles by a gas phase method such as a CVD method. Acetylene, methane, etc. may be used as the hydrocarbon gas. According to these methods, a conductive layer that can be infiltrated by the reaction product of compound (1) can be formed.
  • the present disclosure provides a negative electrode for non-aqueous electrolyte secondary batteries.
  • the negative electrode includes the negative electrode active material (N) according to the present disclosure.
  • the negative electrode mixture layer of the negative electrode contains the negative electrode active material (N) according to the present disclosure.
  • the reaction product of compound (1) is present throughout the negative electrode mixture layer. In other words, the reaction product of compound (1) does not form a layer on the surface of the negative electrode mixture layer, but exists on the surface of each negative electrode active material particle.
  • a nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a nonaqueous electrolyte.
  • the negative electrode includes a negative electrode active material (N).
  • N negative electrode active material
  • the configuration of the negative electrode is not particularly limited except that it contains the negative electrode active material (N).
  • An example of a negative electrode according to the present disclosure includes a negative electrode current collector and a negative electrode mixture layer disposed on the surface of the negative electrode current collector. Except for using the negative electrode active material (N), the method for manufacturing the non-aqueous electrolyte secondary battery according to the present disclosure is not limited, and it may be manufactured by a known method.
  • the configuration of the non-aqueous electrolyte secondary battery according to the present disclosure will be described below.
  • the configuration of the non-aqueous electrolyte secondary battery is not limited to the following configuration.
  • the negative electrode includes, for example, a negative electrode current collector and a negative electrode mixture layer formed on the surface of the negative electrode current collector.
  • the negative electrode mixture layer contains a negative electrode active material (N) as an essential component, and may contain optional components such as a binder, a conductive material, and a thickener.
  • the negative electrode mixture layer may contain a negative electrode active material other than the negative electrode active material (N) in addition to the negative electrode active material (N).
  • Known materials can be used for optional components such as the binder, the conductive material, and the thickener.
  • the negative electrode mixture layer is formed, for example, by applying a negative electrode slurry in which a negative electrode mixture containing a negative electrode active material (N) and a predetermined optional component is dispersed in a dispersion medium on the surface of the negative electrode current collector and drying the slurry. can be formed. The dried coating film may be rolled if necessary.
  • the negative electrode mixture layer may be formed on one surface of the negative electrode current collector, or may be formed on both surfaces.
  • a metal sheet or metal foil is used for the negative electrode current collector.
  • materials for the negative electrode current collector include stainless steel, nickel, nickel alloys, copper, copper alloys, and the like.
  • the positive electrode includes, for example, a positive electrode current collector and a positive electrode mixture layer formed on the surface of the positive electrode current collector.
  • the positive electrode mixture layer contains a positive electrode active material as an essential component, and may contain optional components such as a binder, a conductive material, and a thickener. Known materials can be used for optional components such as the binder, the conductive material, and the thickener.
  • the positive electrode mixture layer can be formed, for example, by applying a positive electrode slurry in which a positive electrode mixture containing a positive electrode active material and a predetermined optional component is dispersed in a dispersion medium on the surface of the positive electrode current collector and drying the slurry. The dried coating film may be rolled if necessary.
  • the positive electrode material mixture layer may be formed on one surface of the positive electrode current collector, or may be formed on both surfaces.
  • a lithium-containing composite oxide can be used as the positive electrode active material.
  • a lithium-containing composite oxide can be used as the positive electrode active material.
  • Me is Na, Mg , Sc, Y, Mn, Fe , Co, Ni, Cu, Zn , is at least one selected from the group consisting of Al, Cr, Pb, Sb, and B).
  • a 0-1.2
  • b 0-0.9
  • c 2.0-2.3. Note that the value a, which indicates the molar ratio of lithium, increases or decreases due to charging and discharging.
  • a positive electrode active material usually has the form of secondary particles in which primary particles are aggregated.
  • the average particle size of the positive electrode active material may be, for example, 2 ⁇ m or more and 20 ⁇ m or less.
  • the average particle size refers to the median size at which the cumulative volume is 50% in the volume-based particle size distribution.
  • the volume-based particle size distribution can be measured with a laser diffraction particle size distribution analyzer.
  • a metal sheet or metal foil is used for the positive electrode current collector.
  • materials for the positive electrode current collector include stainless steel, aluminum, aluminum alloys, and titanium.
  • Examples of conductive materials used for the positive electrode mixture layer and the negative electrode mixture layer include carbon materials such as carbon black (CB), acetylene black (AB), ketjen black (KB), carbon nanotubes (CNT), and graphite. be These may be used individually by 1 type, and may be used in combination of 2 or more type.
  • carbon black CB
  • AB acetylene black
  • KB ketjen black
  • CNT carbon nanotubes
  • graphite graphite
  • binders used for the positive electrode mixture layer and the negative electrode mixture layer include fluororesins (polytetrafluoroethylene, polyvinylidene fluoride, etc.), polyacrylonitrile (PAN), polyimide resins, acrylic resins, polyolefin resins, and the like. be These may be used individually by 1 type, and may be used in combination of 2 or more type.
  • a non-aqueous electrolyte secondary battery usually includes a separator disposed between a positive electrode and a negative electrode.
  • the separator has high ion permeability and moderate mechanical strength and insulation.
  • a microporous membrane, a woven fabric, a nonwoven fabric, or the like can be used as the separator.
  • separator materials include polyolefins (polypropylene, polyethylene, etc.).
  • a non-aqueous electrolyte (non-aqueous electrolyte from another point of view) includes a non-aqueous solvent and a salt (solute) dissolved in the non-aqueous solvent.
  • a salt (solute) is an electrolyte salt that ionizes in a non-aqueous solvent.
  • the salt contains at least lithium salt.
  • the non-aqueous electrolyte may contain additives other than the non-aqueous solvent and salt.
  • the non-aqueous electrolyte may contain compound (1) and/or a reaction product of compound (1).
  • cyclic carbonate for example, cyclic carbonate, chain carbonate, cyclic carboxylate, chain carboxylate, and the like are used.
  • Cyclic carbonates include propylene carbonate (PC), ethylene carbonate (EC), vinylene carbonate (VC) and the like.
  • Chain carbonates include diethyl carbonate (DEC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC) and the like.
  • cyclic carboxylic acid esters include ⁇ -butyrolactone (GBL) and ⁇ -valerolactone (GVL).
  • Chain carboxylic acid esters include methyl acetate, ethyl acetate, propyl acetate, methyl propionate (MP), ethyl propionate (EP) and the like.
  • the non-aqueous solvent may be used singly or in combination of two or more.
  • the non-aqueous electrolytic solution may contain chain carboxylic acid ester in an amount of 1% by mass or more and 90% by mass or less.
  • chain carboxylic acid esters methyl acetate has a particularly low viscosity. Therefore, 90% by mass or more of the chain carboxylic acid ester may be methyl acetate.
  • non-aqueous solvents include cyclic ethers, chain ethers, nitriles such as acetonitrile, and amides such as dimethylformamide.
  • cyclic ethers examples include 1,3-dioxolane, 4-methyl-1,3-dioxolane, tetrahydrofuran, 2-methyltetrahydrofuran, propylene oxide, 1,2-butylene oxide, 1,3-dioxane, 1,4- dioxane, 1,3,5-trioxane, furan, 2-methylfuran, 1,8-cineol, crown ether and the like.
  • linear ethers examples include 1,2-dimethoxyethane, dimethyl ether, diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, dihexyl ether, ethyl vinyl ether, butyl vinyl ether, methylphenyl ether, ethylphenyl ether, butylphenyl ether.
  • pentylphenyl ether methoxytoluene, benzyl ethyl ether, diphenyl ether, dibenzyl ether, o-dimethoxybenzene, 1,2-diethoxyethane, 1,2-dibutoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, 1,1-dimethoxymethane, 1,1-diethoxyethane, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether and the like.
  • These solvents may be fluorinated solvents in which some of the hydrogen atoms are substituted with fluorine atoms.
  • Fluoroethylene carbonate (FEC) may be used as a fluorinated solvent.
  • lithium salts include lithium salts of chlorine-containing acids ( LiClO4 , LiAlCl4 , LiB10Cl10 , etc.), lithium salts of fluorine- containing acids ( LiPF6 , LiPF2O2 , LiBF4 , LiSbF6 , LiAsF6 , LiCF 3 SO 3 , LiCF 3 CO 2 , etc.), lithium salts of fluorine-containing acid imides (LiN(FSO 2 ) 2 , LiN(CF 3 SO 2 ) 2 , LiN(CF 3 SO 2 ) (C 4 F 9 SO 2 ) , LiN( C2F5SO2 ) 2, etc.), lithium halides (LiCl, LiBr, LiI, etc.) can be used. Lithium salts may be used singly or in combination of two or more.
  • the concentration of the lithium salt in the non-aqueous electrolyte may be 0.5 mol/liter or more and 2 mol/liter or less, or may be 1 mol/liter or more and 1.5 mol/liter or less. By controlling the lithium salt concentration within the above range, it is possible to obtain a non-aqueous electrolytic solution with excellent ion conductivity and low viscosity.
  • Additives include 1,3-propanesultone, methylbenzenesulfonate, cyclohexylbenzene, biphenyl, diphenyl ether, and fluorobenzene.
  • An example of a non-aqueous electrolyte secondary battery includes an exterior body, and an electrode group and a non-aqueous electrolyte housed in the exterior body.
  • the electrode group may be a wound electrode group formed by winding a positive electrode and a negative electrode with a separator interposed therebetween.
  • the wound electrode group instead of the wound electrode group, other forms of electrode group may be applied.
  • the electrode group may be a laminated electrode group formed by laminating a positive electrode and a negative electrode with a separator interposed therebetween.
  • the non-aqueous electrolyte secondary battery may be in any shape, for example, cylindrical, square, coin, button, sheet (laminate).
  • FIG. 1 is a partially cutaway plan view schematically showing an example of the structure of a non-aqueous electrolyte secondary battery.
  • FIG. 2 is a cross-sectional view taken along line XX' of FIG.
  • the non-aqueous electrolyte secondary battery 100 is a sheet-type battery, and includes an electrode plate group 4 and an exterior case 5 that accommodates the electrode plate group 4 .
  • the electrode plate group 4 has a structure in which a positive electrode 10, a separator 30 and a negative electrode 20 are laminated in this order, and the positive electrode 10 and the negative electrode 20 face each other with the separator 30 interposed therebetween. Thus, the electrode plate group 4 is formed. Electrode group 4 is impregnated with a non-aqueous electrolyte (not shown).
  • the positive electrode 10 includes a positive electrode mixture layer 1a and a positive electrode current collector 1b.
  • the positive electrode mixture layer 1a is formed on the surface of the positive electrode current collector 1b.
  • the negative electrode 20 includes a negative electrode mixture layer 2a and a negative electrode current collector 2b.
  • the negative electrode mixture layer 2a is formed on the surface of the negative electrode current collector 2b.
  • the negative electrode mixture layer 2a contains the negative electrode active material (N) according to the present disclosure.
  • a positive electrode tab lead 1c is connected to the positive electrode current collector 1b, and a negative electrode tab lead 2c is connected to the negative electrode current collector 2b.
  • the positive electrode tab lead 1c and the negative electrode tab lead 2c extend to the outside of the exterior case 5, respectively.
  • the insulating tab film 6 insulates between the positive electrode tab lead 1c and the outer case 5 and between the negative electrode tab lead 2c and the outer case 5, respectively.
  • a plurality of batteries which are non-aqueous electrolyte secondary batteries, were produced by the following method.
  • the sintered body was pulverized and passed through a mesh of 40 ⁇ m. Then, the particles passed through the mesh were mixed with coal pitch (manufactured by JFE Chemical Co., Ltd., MCP250) to obtain a mixture. Next, by heat-treating the mixture at 800° C. for 5 hours in an inert gas atmosphere, the particle surfaces were coated with conductive carbon to form a conductive layer. The coating amount of the conductive layer was 5% by mass with respect to the total mass of the Si-containing lithium silicate composite oxide particles and the conductive layer. After that, using a sieve, active material particles having an average particle size of 5 ⁇ m and having a conductive layer were obtained.
  • active material particles (a0) the active material particles and the conductive layer formed on the surface thereof may be collectively referred to as "active material particles (a0)".
  • the cross section of the negative electrode active material (a1-1) As a result of observing the cross section of the negative electrode active material (a1-1) with a TEM-EDX device (manufactured by JEOL Ltd., JEM-F200), it was confirmed that a surface layer was formed on the Si-containing lithium silicate composite oxide particles. bottom. It was confirmed that the surface layer contained a conductive layer (conductive carbon layer) and a P1-derived substance (including a reaction product of P1) infiltrated into the conductive layer.
  • a negative electrode slurry was prepared by stirring the mixture using a mixer (TK Hibismix, manufactured by Primix). Next, the negative electrode slurry was applied to one side of a copper foil (negative electrode current collector) to form a coating film.
  • the coating film was dried and then rolled to obtain a laminate (copper foil having a negative electrode mixture layer formed on one side).
  • a negative electrode was obtained by cutting this laminate into a shape including a negative electrode region of 21 mm ⁇ 21 mm and a tab portion.
  • the coating film was dried and then rolled to obtain a laminate (aluminum foil having a positive electrode mixture layer formed on one side).
  • a positive electrode was obtained by cutting this laminate into a shape including a positive electrode region of 20 mm ⁇ 20 mm and a tab portion.
  • EC ethylene carbonate
  • EMC ethyl methyl carbonate
  • DMC dimethyl carbonate
  • the produced electrode group was put into a cylinder from one of the short sides, and part of the Al laminate film was heat-sealed.
  • 0.3 cm 3 of a non-aqueous electrolyte was injected from the short side of the cylinder that was not heat-sealed.
  • the negative electrode mixture layer was impregnated with the non-aqueous electrolyte by performing an operation of allowing the negative electrode mixture layer to stand still under a reduced pressure of 0.08 MPa for 3 minutes and then returning the pressure to atmospheric pressure twice.
  • the end of the Al laminate film on the injected side was heat-sealed to obtain a battery A1 for evaluation.
  • the battery A1 for evaluation was manufactured in a dry air atmosphere with a dew point of ⁇ 60° C. or lower.
  • a battery A2 was produced under the same conditions and method as those for the battery A1, except that the negative electrode active material (a1-2) was used instead of the negative electrode active material (a1-1).
  • ⁇ Battery C1> Except for using vinyltris(2-methoxyethoxy)silane represented by the following formula (commercially available, hereinafter sometimes referred to as "P3") instead of the compound represented by formula (1-1): Then, a negative electrode active material (c1) was produced under the same conditions and method as those for producing the negative electrode active material (a1-1) of Battery A1. In the paste containing the active material particles (a0) and the P3 aqueous solution, the molar amount of P3 per unit mass of the active material particles (a0) is 15 ⁇ mol/g, and The molar amount of Si element contained in P3 was set to 15 ⁇ mol/g.
  • P3 vinyltris(2-methoxyethoxy)silane represented by the following formula (commercially available, hereinafter sometimes referred to as "P3"
  • a battery C1 was produced under the same conditions and method as those for the battery A1, except that the negative electrode active material (c1) was used instead of the negative electrode active material (a1-1).
  • a negative electrode active material (c2) was prepared under the same conditions and method as those for the negative electrode active material (c1) of Battery C1, except that the concentration of the vinyltris(2-methoxyethoxy)silane solution was doubled.
  • the molar amount of P3 per unit mass of the active material particles (a0) is 30 ⁇ mol/g
  • the molar amount of Si element contained in P3 was set to 30 ⁇ mol/g.
  • a battery C2 was produced under the same conditions and method as those for the battery A1, except that the negative electrode active material (c2) was used instead of the negative electrode active material (a1-1).
  • the molar amount of the alkoxysilane-based compound per unit mass of the active material particles (a0) was 15 ⁇ mol/ g.
  • the molar amount of Si element contained in the alkoxysilane-based compound per unit mass of the active material particles (a0) was , 30 ⁇ mol/g.
  • a negative electrode active material (c3) was produced under the same conditions and method as those for producing the negative electrode active material (a1-1) of the battery A1, except that the treatment with the P1 solution was not performed. Furthermore, a battery C3 was fabricated under the same conditions and method as those for the battery A1, except that the negative electrode active material (c3) was used instead of the negative electrode active material (a1-1).
  • Constant current charging is performed at a constant current of 0.5C (1C is the current value for discharging the design capacity in 1 hour) until the battery voltage reaches 4.2V, and the current value reaches 0.02C at a constant voltage of 4.2V. Constant voltage charging was performed until the After resting for 20 minutes, constant current discharge was performed at a constant current of 0.5 C until the battery voltage reached 2.5 V, and resting for 20 minutes. After that, constant current discharge was performed at a constant current of 0.2 C until the battery voltage reached 2.5 V, and the battery was rested for 20 minutes.
  • Batteries C1 to C3 are batteries of comparative examples, and batteries A1 and A2 are batteries according to the present disclosure.
  • the capacity retention rates of batteries A1 and A2 were higher than that of battery C3. This is probably because the presence of compound (1) protected the surface of the active material particles.
  • the capacity retention rates of Batteries A1 and A2 were higher than those of Batteries C1 and C2. It is considered that this is because a reaction product containing R1 is formed by bonding two Si atoms forming a siloxane bond with R1, which enhances the effect of protecting the surface of the active material particles. Although the reason for the improvement in the protective effect is not clear, it is believed that the improvement in the flexibility of the reaction product due to R1 contributes.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Battery Electrode And Active Subsutance (AREA)
PCT/JP2022/030083 2021-08-31 2022-08-05 非水電解質二次電池用の負極活物質、それを用いた非水電解質二次電池、および非水電解質二次電池用の負極活物質の製造方法 Ceased WO2023032592A1 (ja)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP22864178.3A EP4398343A4 (en) 2021-08-31 2022-08-05 NEGATIVE ELECTRODE ACTIVE MATERIAL FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, NONAQUEOUS ELECTROLYTE SECONDARY BATTERY USING SAME, AND METHOD FOR MANUFACTURING NEGATIVE ELECTRODE ACTIVE MATERIAL FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY
US18/686,553 US20240356026A1 (en) 2021-08-31 2022-08-05 Negative electrode active material for non-aqueous electrolyte secondary battery, non-aqueous electrolyte secondary battery using same, and method for producing negative electrode active material for non-aqueous electrolyte secondary battery
CN202280058243.3A CN117897831A (zh) 2021-08-31 2022-08-05 非水电解质二次电池用的负极活性物质、使用了其的非水电解质二次电池、和非水电解质二次电池用的负极活性物质的制造方法
JP2023545388A JPWO2023032592A1 (https=) 2021-08-31 2022-08-05

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2021141746 2021-08-31
JP2021-141746 2021-08-31

Publications (1)

Publication Number Publication Date
WO2023032592A1 true WO2023032592A1 (ja) 2023-03-09

Family

ID=85410987

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/030083 Ceased WO2023032592A1 (ja) 2021-08-31 2022-08-05 非水電解質二次電池用の負極活物質、それを用いた非水電解質二次電池、および非水電解質二次電池用の負極活物質の製造方法

Country Status (5)

Country Link
US (1) US20240356026A1 (https=)
EP (1) EP4398343A4 (https=)
JP (1) JPWO2023032592A1 (https=)
CN (1) CN117897831A (https=)
WO (1) WO2023032592A1 (https=)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003160328A (ja) 2001-09-05 2003-06-03 Shin Etsu Chem Co Ltd リチウム含有酸化珪素粉末及びその製造方法
WO2013024639A1 (ja) * 2011-08-17 2013-02-21 日本電気株式会社 リチウムイオン二次電池用の負極活物質および負極、並びにリチウムイオン二次電池
JP2014150068A (ja) 2012-05-15 2014-08-21 Mitsui Mining & Smelting Co Ltd 非水電解液二次電池用負極活物質
JP2015118871A (ja) * 2013-12-19 2015-06-25 凸版印刷株式会社 非水電解質二次電池用負極、及び非水電解質二次電池
WO2021153396A1 (ja) * 2020-01-30 2021-08-05 パナソニックＩｐマネジメント株式会社 非水電解液用添加剤およびこれを含む非水電解液ならびに非水電解液二次電池
WO2021153395A1 (ja) * 2020-01-30 2021-08-05 パナソニックＩｐマネジメント株式会社 非水電解液用添加剤およびこれを含む非水電解液ならびに非水電解液二次電池

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2022230993A1 (https=) * 2021-04-30 2022-11-03

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003160328A (ja) 2001-09-05 2003-06-03 Shin Etsu Chem Co Ltd リチウム含有酸化珪素粉末及びその製造方法
WO2013024639A1 (ja) * 2011-08-17 2013-02-21 日本電気株式会社 リチウムイオン二次電池用の負極活物質および負極、並びにリチウムイオン二次電池
JP2014150068A (ja) 2012-05-15 2014-08-21 Mitsui Mining & Smelting Co Ltd 非水電解液二次電池用負極活物質
JP2015118871A (ja) * 2013-12-19 2015-06-25 凸版印刷株式会社 非水電解質二次電池用負極、及び非水電解質二次電池
WO2021153396A1 (ja) * 2020-01-30 2021-08-05 パナソニックＩｐマネジメント株式会社 非水電解液用添加剤およびこれを含む非水電解液ならびに非水電解液二次電池
WO2021153395A1 (ja) * 2020-01-30 2021-08-05 パナソニックＩｐマネジメント株式会社 非水電解液用添加剤およびこれを含む非水電解液ならびに非水電解液二次電池

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
IONICS, vol. 24, 2018, pages 3691 - 3698
See also references of EP4398343A4

Also Published As

Publication number Publication date
CN117897831A (zh) 2024-04-16
EP4398343A1 (en) 2024-07-10
EP4398343A4 (en) 2025-07-09
US20240356026A1 (en) 2024-10-24
JPWO2023032592A1 (https=) 2023-03-09

Similar Documents

Publication Publication Date Title
JP6744291B2 (ja) 非水電解質二次電池用負極及び非水電解質二次電池
JP2020529709A (ja) 負極活物質、これを含む負極及びリチウム二次電池
US10770717B2 (en) Composition for secondary battery negative electrode and negative electrode for secondary battery using the same and secondary battery
JP5900926B2 (ja) ナトリウムイオン二次電池用正極活物質、正極及びナトリウムイオン二次電池
WO2023162759A1 (ja) 二次電池
US10847784B2 (en) Negative electrode active material for lithium ion secondary battery and method for producing same
JP5910730B2 (ja) 活物質、およびそれを用いた電極、ならびにリチウムイオン二次電池
CN115004438B (zh) 非水电解液用添加剂和包含其的非水电解液以及非水电解液二次电池
JP6119746B2 (ja) 電解液、これに含まれるエステル化合物の製造方法及びリチウム二次電池
US20240222606A1 (en) Negative electrode active material for non-aqueous electrolyte secondary battery, non-aqueous electrolyte secondary battery using same, and method for producing negative electrode active material for non-aqueous electrolyte secondary battery
CN115023838B (zh) 非水电解液用添加剂和包含其的非水电解液以及非水电解液二次电池
KR20230049046A (ko) 리튬 이차 전지
JPH08231273A (ja) 炭化物の製造方法及びその炭化物の粒子を含んでなる負極
JP2017027772A (ja) リチウムイオン二次電池及びその製造方法
WO2023032592A1 (ja) 非水電解質二次電池用の負極活物質、それを用いた非水電解質二次電池、および非水電解質二次電池用の負極活物質の製造方法
JP5967101B2 (ja) リチウムイオン二次電池用正極材料、リチウムイオン二次電池用正極部材、及びリチウムイオン二次電池
JP2017152361A (ja) 正極及びリチウムイオン二次電池
JP7492775B2 (ja) 非水二次電池用電解液及び非水二次電池
JP6354498B2 (ja) リチウムイオン二次電池用非水電解液、及びそれを用いたリチウムイオン二次電池
US20240413319A1 (en) Lithium Secondary Battery
WO2024247676A1 (ja) 非水電解質二次電池用正極および非水電解質二次電池
JP2025106804A (ja) リチウム二次電池用正極およびそれを含むリチウム二次電池
JP2017152119A (ja) 正極活物質、及びそれを用いた正極ならびにリチウムイオン二次電池
KR20200020039A (ko) 리튬 이차 전지용 양극 활물질 및 이를 포함하는 리튬 이차 전지

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: 22864178

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2023545388

Country of ref document: JP

WWE Wipo information: entry into national phase

Ref document number: 18686553

Country of ref document: US

WWE Wipo information: entry into national phase

Ref document number: 202280058243.3

Country of ref document: CN

WWE Wipo information: entry into national phase

Ref document number: 2022864178

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2022864178

Country of ref document: EP

Effective date: 20240402