JP2012038699A - Silicon alloy negative electrode material excellent in conductivity - Google Patents

Silicon alloy negative electrode material excellent in conductivity Download PDF

Info

Publication number
JP2012038699A
JP2012038699A JP2010229261A JP2010229261A JP2012038699A JP 2012038699 A JP2012038699 A JP 2012038699A JP 2010229261 A JP2010229261 A JP 2010229261A JP 2010229261 A JP2010229261 A JP 2010229261A JP 2012038699 A JP2012038699 A JP 2012038699A
Authority
JP
Japan
Prior art keywords
si
phase
negative electrode
sixcuy
electrode material
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.)
Granted
Application number
JP2010229261A
Other languages
Japanese (ja)
Other versions
JP4739462B1 (en
Inventor
Tomoki Hirono
Masaru Yanagimoto
友紀 廣野
勝 柳本
Original Assignee
Sanyo Special Steel Co Ltd
山陽特殊製鋼株式会社
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
Priority to JP2010161224 priority Critical
Priority to JP2010161224 priority
Application filed by Sanyo Special Steel Co Ltd, 山陽特殊製鋼株式会社 filed Critical Sanyo Special Steel Co Ltd
Priority to JP2010229261A priority patent/JP4739462B1/en
Application granted granted Critical
Publication of JP4739462B1 publication Critical patent/JP4739462B1/en
Publication of JP2012038699A publication Critical patent/JP2012038699A/en
Application status is Active legal-status Critical

Links

Images

Classifications

    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage
    • Y02E60/12Battery technologies with an indirect contribution to GHG emissions mitigation

Abstract

PROBLEM TO BE SOLVED: To provide an Si alloy negative electrode material for an electricity storage device, such as a lithium ion secondary battery and a hybrid capacitor, accompanied by the transfer of lithium ions in charging/discharging.SOLUTION: An Si alloy negative electrode material excellent in conductivity is powder comprising a composite phase consisting of an Si phase and an SixCuy phase comprising an SixCuy alloy that is an intermetallic compound of Si and Cu, while x<y is satisfied in a composition of the SixCuy phase. A composition of the intermetallic compound of the SixCuy alloy is expressed as SiCu.

Description

  The present invention relates to a Si-based alloy negative electrode material that is excellent in electrical conductivity of an electricity storage device that moves lithium ions during charge and discharge, such as a lithium ion secondary battery and a hybrid capacitor.

  In recent years, with the widespread use of portable devices, development of high-performance secondary batteries centered on lithium ion batteries has been actively conducted. Furthermore, lithium-ion secondary batteries as hybrid electric storage devices for automobiles and home use and hybrid capacitors in which the reaction mechanism is applied to the negative electrode are also actively developed. As a negative electrode material for these electricity storage devices, carbonaceous materials such as natural graphite, artificial graphite, and coke that can occlude and release lithium ions are used.

  However, because carbonaceous materials insert lithium ions between the C-planes, the theoretical capacity when used for the negative electrode is limited to 372 mAh / g, and the search for new materials to replace carbonaceous materials for the purpose of increasing capacity is required. Has been actively conducted.

On the other hand, Si has attracted attention as a material that can replace carbonaceous materials. The reason is that since Si can form a compound represented by Li 22 Si 5 and occlude a large amount of lithium, the capacity of the negative electrode can be greatly increased compared to the case where a carbonaceous material is used, As a result, there is a possibility that the storage capacity of the lithium ion secondary battery or the hybrid capacitor can be increased.

  However, when Si is used alone as a negative electrode material, the Si phase is pulverized by repeated expansion during alloying with lithium during charging and contraction during dealloying with lithium during discharging. There has been a problem that the life of the electricity storage device is extremely short due to problems such as the Si phase dropping off from the electrode substrate and the lack of electrical conductivity between the Si phases.

  In addition, Si has poor electrical conductivity compared to carbonaceous materials and metal-based materials, and the efficient movement of electrons associated with charge / discharge is limited. Therefore, as a negative electrode material, a material that supplements conductivity, such as a carbonaceous material. However, even in that case, initial charge / discharge characteristics and charge / discharge characteristics with high efficiency are also problems.

  As a method for solving the drawbacks when using such a Si phase as a negative electrode, a material in which at least a part of a parent lithium phase such as Si is surrounded by an intermetallic compound of Si and a metal typified by a transition metal, or the like Manufacturing methods have been proposed. For example, Japanese Patent Laid-Open No. 2001-297757 (Patent Document 1) and Japanese Patent Laid-Open No. 10-31804 (Patent Document 2) are known.

As another solution, an electrode in which a phase of an active material containing a Si phase is coated with a conductive material such as Cu that does not alloy with lithium, and a method for manufacturing the same have been proposed. For example, Japanese Unexamined Patent Application Publication No. 2004-228059 (Patent Document 3) and Japanese Unexamined Patent Application Publication No. 2005-44672 (Patent Document 4) are known.
JP 2001-297757 A JP 10-31804 A JP 2004-228059 A JP 2005-44672 A

  However, in the above-described method of coating the active material phase with a conductive material such as Cu, it is necessary to coat the active material containing the Si phase with a method such as plating before or after the step of forming the active material on the electrode. There is a problem that it takes time and labor from the industrial point of view, such as control of the coating film thickness.

  In addition, a material in which at least a part of a parent lithium phase such as Si is surrounded by an intermetallic compound is an industrially preferable process because a parent lithium phase and an intermetallic compound are formed during a solidification process after melting. In the proposed combination of elements, most of the intermetallic compounds that are in equilibrium with the Si phase become Si-rich compounds that are inferior in electrical conductivity. There was a drawback of poor discharge characteristics. In addition, there is no proposal related to the composition of an intermetallic compound excellent in electrical conductivity that can solve these problems.

In order to solve the above-mentioned problems, the inventors have made extensive developments. As a result, the intermetallic compound surrounding the Si phase is a metal intermetallic compound with Cu element among many intermetallic compounds with the Si phase. The compound forms SiCu 3 with excellent electrical conductivity and a composite phase composed of Si phase and SiCu 3 alloy, making use of the large discharge capacity of Si and making the inherent low conductivity of Si conductive. It has been found that both the discharge capacity and the cycle life are good due to the effect of SiCu 3 excellent in the present invention. The gist of the invention is
(1) Conductivity characterized in that it is a powder composed of a composite phase of a SixCuy phase composed of a SixCuy alloy that is an intermetallic compound of Si phase and Si and Cu, and the composition of the SixCuy phase is x <y. Si-based alloy negative electrode material with excellent resistance.

(2) Substituting a part of Si constituting the Si phase in (1) with one or more elements selected from the group consisting of C, Ge, Sn, Pb, Al and P, and replacing Si with A Si-based alloy negative electrode material excellent in conductivity, characterized by having a main Si phase.
(3) A Si-based alloy negative electrode material excellent in conductivity, characterized in that the composition of the intermetallic compound which is the SixCuy alloy in the above (1) or (2) is SiCu 3 .

(4) In any one of the above (1) to (3), the average particle diameter of the Si phase or Si phase having Si as the main phase is 10 μm or less, and at least one part of the Si phase is surrounded by the SixCuy phase A Si-based alloy negative electrode material excellent in conductivity, characterized by comprising:
(5) The conductivity according to any one of (1) to (4), wherein the initial discharge capacity is 1000 mAh / g or more and the discharge capacity at the 100th cycle is 372 mAh / g or more. Si-based alloy negative electrode material with excellent resistance.

As described above, by using SiCu 3 having excellent electrical conductivity according to the present invention, it is possible to supplement the conductivity of Si, and to reliably obtain a negative electrode material having a good cycle life, and to have a discharge capacity and a cycle life. All of these are good and exhibit an excellent effect of enabling the provision of a secondary negative electrode material.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a phase diagram of the Si—Cu binary system. As shown in this figure, when the Si—Cu alloy melt is cooled, Si is precipitated as the primary crystal when the liquidus temperature is reached (eg, 1200 ° C. in the case of Si: 64 atomic% —Cu: 36 atomic%). Begin to. This primary crystal precipitates as a granular crystal if the cooling rate is high as in the liquid quenching method or the atomizing method, and when the temperature reaches the solidus temperature (802 ° C.), a eutectic reaction between Si and SiCu 3 occurs and solidification is completed. To do. Thus, in the phase diagram on the Si rich side, it is a eutectic reaction between the Si phase and the SiCu 3 phase, and the Si phase surrounds the SiCu 3 phase.

On the other hand, as a combination of elements that alloy Si other than Cu, for example, Fe-Si, Ni-Si, Mn-Si, Co-Si, Cr-Si, Si-W, Mo-Si, Nb-Si, Si -Ti, Si-V, etc. are conceivable. However, it will both FeSi 2, NiSi 2, CoSi 2 , CrSi 2, WSi 2, MoSi 2, MnSi 2, NbSi 2, TiSi 2, VSi 2 and the Si-rich composition remains than metal elements .

The combination of Si and the transition element described above equilibrates with the Si phase as the only Cu-rich compound (SiCu 3 ). When the resistance value of this Cu-rich compound (SiCu 3 ) is examined, it is found that SiCu 3 : 16.3 × 10 −4 Ω · m, similarly FeSi 2 : 1000 × 10 −4 Ω · m, NiSi 2 : 50 × It can be seen that 10 −4 Ω · m, CoSi 2 : 18 × 10 −4 Ω · m and SiCu 3 have lower resistance values than other silicide compounds.

There are two factors that have the lowest resistance value of SiCu 3 , and the first is that SiCu 3 has a metal-rich composition compared to other silicide compounds. Secondly, when focusing on the transition metal element of the raw material, Cu: 1.73 × 10 −4 Ω · m, Fe: 10 × 10 −4 Ω · m, Ni: 11.8 × 10 −4 Ω · m , Co: 9.71 × 10 −4 Ω · m, and simple substance Cu had a very low resistance value compared to other transition metal elements, and was a combination of Si and the transition metal having the lowest resistance value It is.

As can be seen from the above, the combination of Si and transition metal element having the lowest resistance value among the transition metal silicide compounds is Si and Cu. This is because Si and Cu, which are raw materials of transition metal silicide compounds, have extremely low resistance values compared to other single transition metal elements, and can never be obtained by a combination of transition metal elements of Si phase and Si. This is because a metal-rich compound phase with the element (SixCuy (x <y)), for example, a SiCu 3 phase can be formed. Thus, since the resistance value is the lowest, SiCu 3 is an Si-rich intermetallic compound (FeSi 2 , NiSi 2 , CoSi 2 , CrSi 2 , WSi 2 , MoSi 2 , MnSi 2 , NbSi 2 , TiSi 2 , It can be seen that the electric conductivity is higher than that of VSi 2 ).

From the above, it can be seen that only Cu in the combination of Si and the transition metal element precipitates the Si phase and the metal-rich compound (SiCu 3 ) phase by eutectic reaction, and this SiCu 3 is Si—Cu. It is also known from the binary phase diagram that in a Si-rich composition (for example, Si: 64 atom% -Cu: 36 atom%), the Si phase surrounds the SiCu 3 phase. This allows the SiCu 3 phase to precipitate around the Si phase, which has a much higher electrical conductivity than the combination of Si and other transition metal elements, so that the SiCu 3 phase plays a role in supplementing the poor electrical conductivity of Si. He will do it.

Furthermore, since the SiCu 3 phase is not alloyed with lithium, the SiCu 3 phase itself does not expand or contract even if it is repeatedly charged (lithium enters the negative electrode) -discharge (lithium comes out from the negative electrode). On the contrary, since the SiCu 3 phase has a lower hardness than Si, it can also be a phase that relieves stress due to a large volume expansion / contraction change of Si caused by the reaction between Si and lithium.

  Si is a main phase, and is a group of phases composed of one or more elements that can be reversibly combined and sequestered with Li. One or more elements selected from the group consisting of C, Ge, Sn, Pb, Al and P, which are such elements, may be substituted as part of Si, and these elements may be substituted. When forming a solid solution of a mold, the composition ratio is not particularly limited, but the ratio of C, Ge, Sn, Pb, Al, P is M, where these are M, and when Si is 1, the total of M substituted for Si Is preferably less than 0.5.

Further, in the SixCuy alloy, which is an alloy of Si and Cu that forms an intermetallic compound, the composition of the SixCuy phase needs to be x <y. For example, FeSi 2 does not become Fe rich. Since an alloy of Fe element and Si forms a Si-rich compound phase, the electrical conductivity is inferior, and the electrical conductivity between Si phases is prevented from being lowered due to the refinement of Si caused by repeated charge and discharge. Therefore, the composition of the SixCuy phase is set to x <y. Preferably, x = 1 and y = 3.

  Further, the average particle diameter of the Si phase or Si phase having Si as the main phase is 10 μm or less, preferably 5 μm or less. This is because if the average particle size is large, the cycle life is reduced. The reaction between Si and lithium occurs at the contact portion of the electrolyte. For large Si particles having a maximum particle size exceeding 10 μm, the reaction with lithium during the initial charging reaction stops only at the surface part of the Si particle in contact with the electrolytic solution, and it takes time until the electrolytic solution penetrates. The internal reaction will not be performed.

  And, it becomes impossible to withstand the stress caused by the volume expansion / contraction difference between the Si surface and the internal volume caused by the insertion reaction of lithium into the initial Si, the surface layer Si cracks, and the Si peels off from the current collector, By becoming an electrically isolated Si island that cannot be removed, those Si cannot be used from the next cycle. At that time, depending on the cracking method, there is a risk of peeling from the current collector while containing unreacted Si or becoming an electrically isolated state where current cannot be collected. Furthermore, when the surface Si disappears and a new unreacted Si surface appears, the above phenomenon is repeated, and the capacity rapidly decreases in the initial few cycles.

  From the above, it has been found that when the average particle size of Si is large, the reaction with lithium stops during the initial charge reaction only in the surface layer portion of the Si particle in contact with the electrolyte. Therefore, measures are taken in advance to increase the Si surface area with which the electrolytic solution comes into contact by making Si particles fine particles and increasing the specific surface area of the reacting Si. This increases the initial reaction rate between lithium and Si, makes it a fine phase up to a particle size where there is no unreacted Si, and removes Si from the current collector or electrically isolated Si islands that cannot collect current. This prevents a sudden drop in the capacity of the initial few cycles due to the repetition of the above-described Si peeling and electrical isolation phenomenon. Therefore, the upper limit is set to 10 μm. The smaller the lower limit of the particle size, the better.

FIG. 2 shows a cross-sectional SEM image of the Si—Cu alloy powder. As shown in this figure, the black portion is the embedded resin 1, the gray portion is the Si phase 2, and the white portion is the SiCu 3 phase 3. In particular, when attention is paid to the central Si—Cu particle, the gray Si phase 2 is surrounded by the white SiCu 3 phase in the portion A inside the particle. However, it can be seen that in the portion B of the particle surface portion, the gray Si phase 2 is exposed on the particle surface. Thus, at least a part of the Si phase is surrounded by the SixCuy phase.

Hereinafter, the present invention will be specifically described with reference to examples.
A flaky powder of a negative electrode material having the composition shown in Table 1 was prepared by a liquid quenching method and mechanical milling as described below. A raw material having a predetermined composition is placed in a quartz tube having pores at the bottom, melted at a high frequency in an Ar atmosphere to form a molten metal, and after the molten metal is discharged onto the surface of a rotating copper roll, the ribbon is quenched by a rapid cooling effect by the copper roll Was made. Thereafter, the produced ribbon was sealed in a zirconia pot container together with zirconia balls in an Ar atmosphere, and powdered by mechanical milling. In order to evaluate the negative electrode performance of the obtained negative electrode material, the powder of each negative electrode material was classified into an average particle size of 10 μm or less to prepare a negative electrode. In order to evaluate the electrode performance of the negative electrode as a single electrode, a so-called bipolar coin-type cell using lithium metal as a counter electrode was used.

  First, a negative electrode active material (such as Si-Cu), a conductive material (acetylene black), a binder (polyvinylidene fluoride) is weighed with an electronic balance, and mixed with a dispersion (N-methylpyrrolidone). It apply | coated uniformly on the electrical power collector (Cu foil). After coating, the solvent was evaporated by drying under reduced pressure with a vacuum dryer, and then punched into a shape suitable for a coin cell. Similarly, lithium for the counter electrode was punched into a shape suitable for the coin cell.

Electrolytic solution used for lithium ion batteries (3: 7 mixed solvent of ethylene carbonate and dimethyl carbonate was used, LiPF 6 (lithium hexafluorophosphate) was used as the supporting electrolyte, and 1 mol was dissolved in the electrolytic solution) Since the cell must be handled in an inert atmosphere with dew point control, the cells were all assembled in an inert atmosphere glove box. The separator was cut out into a shape suitable for a coin cell, and then held in the electrolyte for several hours under reduced pressure in order to sufficiently permeate the electrolyte into the separator. Thereafter, the negative electrode, separator, and counter electrode lithium punched in the previous process were combined in this order, and the battery was fully filled with the electrolyte.

The measurement of charge capacity and discharge capacity was performed using the above-mentioned bipolar cell, at a temperature of 25 ° C., and charged at a current density of 0.50 mA / cm 2 until the same potential (0 V) as that of the metal lithium electrode. Discharge was performed up to 1.5 V at a current value (0.50 mA / cm 2 ), and this charge-discharge was taken as one cycle. The charge capacity at the first cycle at this time was evaluated as the initial capacity value. The discharge capacity obtained by this evaluation, that is, the amount of lithium released from the negative electrode was 1000 mAh / g or more per mass of the negative electrode (about 4000 mAh / cm 3 or more when converted to volume), and passed.

Further, as the cycle life, the discharge capacity of the first cycle was measured, and the discharge capacity of the negative electrode using the negative electrode material was measured. The discharge capacity of the 100th cycle was measured, and used as a measure of the cycle life. The discharge capacity at the 100th cycle (the amount of lithium released from the negative electrode) obtained by this evaluation was 372 mAh / g or higher, which is the theoretical discharge capacity of the current graphite electrode, that is, about 867 mAh / cm 3 or higher. Table 2 shows the results of the discharge capacity at the first cycle and the discharge capacity at the 100th cycle thus obtained.

As shown in Table 1 and Table 2, 1 to 14 are examples of the present invention. 15 to 26 show comparative examples.

Invention Example No. Nos. 1 to 14 indicate that the discharge capacity at the first cycle is 1000 mAh / g or more, that is, about 4000 mAh / cm 3 or more, and are acceptable as battery negative electrodes. Further, the discharge capacity after 100 cycles showed a value exceeding 372 mAh / g which is the capacity of the current graphite electrode, that is, a value exceeding about 867 mAh / cm 3 . Even with the same composition, Comparative Example No. In Nos. 15 and 16, since the average particle size of the Si phase size exceeds 10 μm, the discharge capacity after 100 cycles is small, and the conditions of the present invention are not satisfied. Furthermore, Example No. of the present invention. Since 1 and 2 are 5 μm or less, the average particle size of the Si phase being considered to be more preferable, the discharge capacity after 100 cycles showed a value more than twice the theoretical discharge capacity of the graphite electrode.

Comparative Example No. 17-26, the transition metal silicide phase (NiSi 2, FeSi 2, MnSi 2, CoSi 2, CrSi 2, WSi 2, MoSi 2, NbSi 2, TiSi 2, VSi 2) transition metal elements (Ni, Fe, Compared with Mn, Co, Cr, W, Mo, Nb, Ti, and V), the electrical discharge is inferior because of Si-rich, so the initial discharge characteristics are poor. Similarly, the discharge capacity after 100 cycles is also bad.

Comparative Example No. Since 17 to 26 are all Si-rich intermetallic compound compositions, they have lower electrical conductivity than SiCu 3 as in the present invention example, the reaction efficiency of Si and Li due to charge / discharge is poor, and Si The electrical conductivity between phases is lowered, and the charge / discharge life is also inferior. On the other hand, the present invention example No. Nos. 1 to 14 satisfy the conditions of the present invention, so that they have high electrical conductivity and do not react with lithium, so that the stress of volume expansion / contraction of Si due to the reaction between Si and Li during charge / discharge can be reduced. While becoming a phase which eases, the electrical conductivity fall between Si phases by the refinement | miniaturization of Si which arises by repetition of charging / discharging can also be prevented, and a charging / discharging lifetime can be improved.

As described above, the metal-rich compound phase exhibits extremely high thermal conductivity among Si intermetallic compounds, so it has excellent thermal conductivity when solidified from molten alloy and suppresses the growth of the primary Si phase. Can be made fine. Further, the SiCu 3 phase is excellent in electrical conductivity, and exhibits a very excellent effect of improving both the charge / discharge capacity and the charge / discharge life due to a synergistic effect.

It is a figure which shows the phase diagram of Si-Cu binary system. It is a figure which shows the cross-sectional SEM image of Si-Cu alloy powder.

1 Embedded resin 2 Si phase 3 SiCu 3 phase



Patent Applicant Sanyo Special Steel Co., Ltd.
Attorney: Attorney Shiina

In order to solve the above-mentioned problems, the inventors have made extensive developments. As a result, the intermetallic compound surrounding the Si phase is a metal intermetallic compound with Cu element among many intermetallic compounds with the Si phase. The compound forms SiCu 3 with excellent electrical conductivity and a composite phase composed of Si phase and SiCu 3 alloy, making use of the large discharge capacity of Si and making the inherent low conductivity of Si conductive. the superior SiCu 3 supplements effect, leading to see out the invention that it is better neither of the discharge capacity and cycle life. The gist of the invention is
(1) A SixCuy alloy, which is an intermetallic compound of Si phase and Si and Cu, is a powder composed of a composite phase of SiCu 3 phase, and a part of Si constituting the Si phase is C, Ge, Sn, Pb. , Si and mainly Si substituted with one or more elements selected from the group consisting of Al and P, the average particle size of the Si phase mainly Si is 10 μm or less, By having at least a part of the Si phase surrounded by a SiCu 3 phase, the initial discharge capacity is 1000 mAh / g or more, and the discharge capacity at the 100th cycle is 372 mAh / g or more. Si-based alloy negative electrode material.

Invention Example No. 1 to 8 show discharge capacities of the first cycle of 1000 mAh / g or more, that is, about 4000 mAh / cm 3 or more, and are acceptable as battery negative electrodes. Further, the discharge capacity after 100 cycles showed a value exceeding 372 mAh / g which is the capacity of the current graphite electrode, that is, a value exceeding about 867 mAh / cm 3 . Even with the same composition, Comparative Example No. In Nos . 9 and 10 , since the average particle size of the Si phase size exceeds 10 μm, the discharge capacity after 100 cycles is small, and the conditions of the present invention are not satisfied.

Comparative Example No. 11-20, transition metal silicide phase (NiSi 2, FeSi 2, MnSi 2, CoSi 2, CrSi 2, WSi 2, MoSi 2, NbSi 2, TiSi 2, VSi 2) transition metal elements (Ni, Fe, Compared with Mn, Co, Cr, W, Mo, Nb, Ti, and V), the electrical discharge is inferior because of Si-rich, so the initial discharge characteristics are poor. Similarly, the discharge capacity after 100 cycles is also bad.

Comparative Example No. Since 11 to 20 are all Si-rich intermetallic compound compositions, the electrical conductivity is low compared to SiCu 3 as in the present invention example, the reaction efficiency of Si and Li due to charge and discharge is poor, and Si The electrical conductivity between phases is lowered, and the charge / discharge life is also inferior. On the other hand, the present invention example No. Nos. 1 to 8 satisfy the conditions of the present invention, so that they have high electrical conductivity and do not react with lithium, so that the volume expansion / contraction stress of Si due to the reaction between Si and Li during charge / discharge can be reduced. While becoming a phase which eases, the electrical conductivity fall between Si phases by the refinement | miniaturization of Si which arises by repetition of charging / discharging can also be prevented, and a charging / discharging lifetime can be improved.

Claims (5)

  1. Si having excellent electrical conductivity, characterized in that it is a powder composed of a composite phase of a SixCuy phase composed of a SixCuy alloy which is an intermetallic compound of Si phase and Si and Cu, and the composition of the SixCuy phase is x <y. Alloy negative electrode material.
  2. A part of Si constituting the Si phase according to claim 1 is replaced with one or more elements selected from the group consisting of C, Ge, Sn, Pb, Al and P, and Si is the main Si. A Si-based alloy negative electrode material excellent in conductivity, characterized by being in a phase.
  3. In claim 1 or 2, Si-based alloy negative electrode material having excellent conductivity, wherein the composition of the intermetallic compound is SixCuy alloy is SiCu 3.
  4. The average particle size of the Si phase or Si phase containing Si as a main phase is 10 μm or less, and at least a part of the Si phase is surrounded by a SixCuy phase. Si-based alloy negative electrode material with excellent electrical conductivity.
  5. The Si-based alloy negative electrode having excellent conductivity according to any one of claims 1 to 4, wherein an initial discharge capacity is 1000 mAh / g or more and a discharge capacity at the 100th cycle is 372 mAh / g or more. material.
JP2010229261A 2010-07-16 2010-10-12 Si-based alloy negative electrode material with excellent conductivity Active JP4739462B1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP2010161224 2010-07-16
JP2010161224 2010-07-16
JP2010229261A JP4739462B1 (en) 2010-07-16 2010-10-12 Si-based alloy negative electrode material with excellent conductivity

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2010229261A JP4739462B1 (en) 2010-07-16 2010-10-12 Si-based alloy negative electrode material with excellent conductivity

Publications (2)

Publication Number Publication Date
JP4739462B1 JP4739462B1 (en) 2011-08-03
JP2012038699A true JP2012038699A (en) 2012-02-23

Family

ID=44541358

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2010229261A Active JP4739462B1 (en) 2010-07-16 2010-10-12 Si-based alloy negative electrode material with excellent conductivity

Country Status (1)

Country Link
JP (1) JP4739462B1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012099056A1 (en) * 2011-01-17 2012-07-26 山陽特殊製鋼株式会社 Si alloy powder for negative electrode of lithium-ion secondary cell, and method for manufacturing same
JP2014157827A (en) * 2014-04-10 2014-08-28 Furukawa Electric Co Ltd:The Negative electrode for nonaqueous electrolytic secondary battery use and nonaqueous electrolytic secondary battery arranged by use thereof
JP2014160554A (en) * 2013-02-19 2014-09-04 Sanyo Special Steel Co Ltd Si-BASED ALLOY NEGATIVE ELECTRODE MATERIAL FOR POWER STORAGE DEVICE, AND ELECTRODE USING THE SAME

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5652161B2 (en) * 2010-11-26 2015-01-14 日産自動車株式会社 Si alloy negative electrode active material for electrical devices
JP2013122905A (en) * 2011-11-10 2013-06-20 Sanyo Special Steel Co Ltd Scale-like silicon-based alloy negative electrode material
US9373839B2 (en) 2011-12-13 2016-06-21 Samsung Sdi Co., Ltd. Negative electrode active material and secondary battery including the same
JP6322362B2 (en) * 2012-02-01 2018-05-09 山陽特殊製鋼株式会社 Si alloy negative electrode material
US20150041707A1 (en) * 2013-08-08 2015-02-12 Mk Electron Co., Ltd. Negative active material for secondary battery and method of manufacturing the same

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004228059A (en) * 2002-11-29 2004-08-12 Mitsui Mining & Smelting Co Ltd Negative electrode for lithium secondary battery, method of manufacturing the same, and lithium secondary battery
JP2004362895A (en) * 2003-06-03 2004-12-24 Sony Corp Negative electrode material, and battery using it
JP2007149685A (en) * 2005-11-29 2007-06-14 Samsung Sdi Co Ltd Anode active material for lithium secondary battery and lithium secondary battery containing the same
JP2010135336A (en) * 2003-03-26 2010-06-17 Canon Inc Electrode material for lithium secondary battery, electrode structure having this electrode material, and secondary battery having this electrode structure

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004228059A (en) * 2002-11-29 2004-08-12 Mitsui Mining & Smelting Co Ltd Negative electrode for lithium secondary battery, method of manufacturing the same, and lithium secondary battery
JP2010135336A (en) * 2003-03-26 2010-06-17 Canon Inc Electrode material for lithium secondary battery, electrode structure having this electrode material, and secondary battery having this electrode structure
JP2004362895A (en) * 2003-06-03 2004-12-24 Sony Corp Negative electrode material, and battery using it
JP2007149685A (en) * 2005-11-29 2007-06-14 Samsung Sdi Co Ltd Anode active material for lithium secondary battery and lithium secondary battery containing the same

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012099056A1 (en) * 2011-01-17 2012-07-26 山陽特殊製鋼株式会社 Si alloy powder for negative electrode of lithium-ion secondary cell, and method for manufacturing same
US9397334B2 (en) 2011-01-17 2016-07-19 Sanyo Special Steel Co., Ltd. Si alloy powder for negative electrode of lithium-ion secondary cell, and method for manufacturing same
JP2014160554A (en) * 2013-02-19 2014-09-04 Sanyo Special Steel Co Ltd Si-BASED ALLOY NEGATIVE ELECTRODE MATERIAL FOR POWER STORAGE DEVICE, AND ELECTRODE USING THE SAME
JP2014157827A (en) * 2014-04-10 2014-08-28 Furukawa Electric Co Ltd:The Negative electrode for nonaqueous electrolytic secondary battery use and nonaqueous electrolytic secondary battery arranged by use thereof

Also Published As

Publication number Publication date
JP4739462B1 (en) 2011-08-03

Similar Documents

Publication Publication Date Title
US8071238B2 (en) Silicon-containing alloys useful as electrodes for lithium-ion batteries
JP4865556B2 (en) Multiphase silicon-containing electrodes for lithium ion batteries
US7297446B2 (en) Negative electrode for rechargeable lithium battery and method for fabrication thereof
US7618678B2 (en) Carbon-coated silicon particle powders as the anode material for lithium ion batteries and the method of making the same
JP4022889B2 (en) Electrolyte and battery
US7875388B2 (en) Electrodes including polyacrylate binders and methods of making and using the same
CN100346507C (en) battery
US20060046144A1 (en) Anode composition for lithium ion battery
JP4471836B2 (en) Negative electrode for lithium secondary battery and lithium secondary battery
TWI416779B (en) Method of using an electrochemical cell
CN101005133B (en) Negative active material for rechargeable lithium battery and rechargeable lithium battery
US6946223B2 (en) Negative electrode for lithium secondary battery and lithium secondary battery
KR100859687B1 (en) Negative active material for rechargeable lithium battery and rechargeable lithium battery
JP2009538513A (en) Electrode composition, process for producing the same, and lithium ion battery including the same
JP4033720B2 (en) Negative electrode for lithium secondary battery and lithium secondary battery
JP4855346B2 (en) Negative electrode active material for lithium secondary battery and lithium secondary battery including the same
JP3726958B2 (en) Battery
US8338022B2 (en) Lithium secondary battery and method for manufacturing the same
CN101233634B (en) Alloy compositions for lithium ion batteries
JP4212392B2 (en) Negative electrode for lithium secondary battery and lithium secondary battery
JP2004319469A (en) Negative electrode active substance and nonaqueous electrolyte secondary cell
JP4207055B2 (en) Method for producing SiOx (x &lt;1)
JP2009099328A (en) Negative electrode, and battery
US8980428B2 (en) Porous silicon particles and complex porous silicon particles, and method for producing both
JP3846661B2 (en) Lithium secondary battery

Legal Events

Date Code Title Description
A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20110318

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20110426

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20110427

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140513

Year of fee payment: 3

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250