JP4368139B2 - Anode material for non-aqueous electrolyte secondary battery - Google Patents

Anode material for non-aqueous electrolyte secondary battery Download PDF

Info

Publication number
JP4368139B2
JP4368139B2 JP2003129705A JP2003129705A JP4368139B2 JP 4368139 B2 JP4368139 B2 JP 4368139B2 JP 2003129705 A JP2003129705 A JP 2003129705A JP 2003129705 A JP2003129705 A JP 2003129705A JP 4368139 B2 JP4368139 B2 JP 4368139B2
Authority
JP
Japan
Prior art keywords
negative electrode
solid phase
secondary battery
electrolyte secondary
non
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.)
Expired - Fee Related
Application number
JP2003129705A
Other languages
Japanese (ja)
Other versions
JP2004335272A (en
Inventor
貴之 中本
秀明 大山
治成 島村
靖彦 美藤
Original Assignee
パナソニック株式会社
住友金属工業株式会社
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
Application filed by パナソニック株式会社, 住友金属工業株式会社 filed Critical パナソニック株式会社
Priority to JP2003129705A priority Critical patent/JP4368139B2/en
Publication of JP2004335272A publication Critical patent/JP2004335272A/en
Application granted granted Critical
Publication of JP4368139B2 publication Critical patent/JP4368139B2/en
Application status is Expired - Fee Related legal-status Critical
Anticipated expiration 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
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/60Other road transportation technologies with climate change mitigation effect
    • Y02T10/70Energy storage for electromobility
    • Y02T10/7005Batteries
    • Y02T10/7011Lithium ion battery

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improved negative electrode material for a non-aqueous electrolyte secondary battery, and more particularly, to a negative electrode material that provides a non-aqueous electrolyte secondary battery excellent in charge / discharge cycle characteristics and high rate discharge characteristics. A non-aqueous electrolyte secondary battery comprising the negative electrode material for a non-aqueous electrolyte secondary battery of the present invention is a portable information terminal, a portable electronic device, a small electric power storage device for home use, a motorcycle powered by a motor, an electric vehicle, It is suitable for a hybrid electric vehicle.
[0002]
[Prior art]
Nonaqueous electrolyte secondary batteries, particularly lithium secondary batteries, having features such as high electromotive force and high energy density, have been conventionally used as main power sources for mobile communication devices and portable electronic devices. As the negative electrode material, lithium metal or graphite is mainly used. In particular, when lithium metal is used, the highest energy density can be obtained.
[0003]
However, a lithium secondary battery using lithium metal as a negative electrode material has a drawback that dendrites deposited on the negative electrode during charging grow by repeated charge and discharge, penetrate the separator, and cause an internal short circuit. In addition, for a lithium secondary battery using graphite as a negative electrode material, the theoretical capacity of graphite (372 mAh / g) is about 10% smaller than the theoretical capacity of lithium metal, which is sufficient for the recent demand for higher energy density. There is a drawback that it cannot respond to.
[0004]
Therefore, in recent years, the use of silicon (Si) as a new negative electrode material has been studied. Silicon theoretically contains up to 22 lithium ions per 5 silicon atoms, ie Li twenty two Si Five It is possible to occlude until the composition becomes. The theoretical capacity of silicon is 4199 mAh / g, which is much larger than the theoretical capacity of graphite. In addition, when silicon is used as the negative electrode material, metal lithium does not precipitate on the surface of the negative electrode during normal charging, so there is no risk of an internal short circuit due to dendrite growth.
[0005]
Many negative electrode materials using such silicon have been proposed so far (see, for example, Patent Documents 1 to 3). In Patent Document 1, a core particle composed of a solid phase A and a composite particle composed of a coating layer of a solid phase B that covers all or part of the surface of the core particle is proposed as a negative electrode material. For the solid phase A, silicon, a solid solution containing silicon, or an intermetallic compound is used. For the solid phase B, silicon, a solid solution containing silicon, or an intermetallic compound is used so that the composition differs from that of the solid phase A. Although not specified in Patent Document 1, since the composite particles are obtained by cooling the molten alloy in an electric furnace, both the solid phase A and the solid phase B are crystalline phases.
[0006]
[Patent Document 1]
JP 2000-30703 A (page 4, [0018])
[Patent Document 2]
JP 2000-243389 A
[Patent Document 3]
JP-A-10-83817
[0007]
[Problems to be solved by the invention]
Silicon expands about four times in volume when it reacts with lithium. For this reason, when charging / discharging of a lithium secondary battery using silicon as a negative electrode material is repeated, there is a problem that a large internal strain is generated in the silicon particles, cracks are generated, and the particles are easily pulverized. Such pulverization leads to deterioration of charge / discharge cycle characteristics of the battery.
[0008]
As proposed in Patent Document 1, it is possible to suppress the pulverization of particles to some extent by alloying silicon with other elements.
However, when both solid phase A and solid phase B are composed of a crystalline phase, it is difficult to sufficiently suppress pulverization.
[0009]
The present invention has been made in view of the above, and provides a negative electrode material that provides a non-aqueous electrolyte secondary battery excellent in charge / discharge cycle characteristics and high-rate discharge characteristics by sufficiently suppressing silicon pulverization. With the goal.
[0010]
[Means for Solving the Problems]
That is, the present invention is a negative electrode material for a non-aqueous electrolyte secondary battery comprising composite particles in which a coating layer comprising a solid phase B is formed on part or all of the surface of a core particle comprising a solid phase A, The solid phase A is an amorphous alloy phase containing Si and at least one selected from the group consisting of Sb and P or B, and the solid phase B is Si, Mg, Ti, Zr, V, Mo , W, Mn, Fe, Cu, Co and a crystalline alloy phase containing at least one selected from the group consisting of Ni The solid phase A has a Si content of 95 to 99.99% by weight, and the total content of Sb, P and B in the solid phase A is 0.01 to 5% by weight. The present invention relates to a negative electrode material for a non-aqueous electrolyte secondary battery.
[0011]
in front The weight ratio of the nucleus particles to the coating layer is preferably 5:95 to 40:60.
[0012]
The solid phase B is preferably composed of a crystalline alloy phase of Si and Ti, and in particular the composition formula is TiSi. 2 It is preferable to consist of the intermetallic compound phase represented by these.
[0013]
The present invention also relates to a negative electrode for a nonaqueous electrolyte secondary battery provided with the above negative electrode material for a nonaqueous electrolyte secondary battery as a material that absorbs and releases lithium ions.
[0014]
The present invention also provides a non-aqueous electrolyte comprising the non-aqueous electrolyte secondary battery negative electrode, a positive electrode capable of occluding and releasing lithium, a separator interposed between the negative electrode and the positive electrode, and a non-aqueous electrolyte. The present invention relates to a secondary battery.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The negative electrode material for a non-aqueous electrolyte secondary battery of the present invention is composed of composite particles in which a coating layer composed of a solid phase B is formed on a part or all of the surface of a core particle composed of a solid phase A. , Si and at least one selected from the group consisting of Sb and P, or B, which is an amorphous alloy phase, where the solid phase B is Si, Mg, Ti, Zr, V, Mo, W, Mn A crystalline alloy phase containing at least one selected from the group consisting of Fe, Cu, Co and Ni.
That is, the solid phase A and the solid phase B are different in composition and crystal state.
[0016]
In the present invention, the amorphous alloy phase means that there is no peak attributed to the crystal plane of the alloy phase in the diffraction pattern obtained by the wide-angle X-ray diffraction method. The crystalline alloy phase means that there is a peak attributed to the crystal plane of the alloy phase in a diffraction pattern obtained by a wide-angle X-ray diffraction method. “No peak” means that the crystallite size after annealing (held at 500 ° C. for 1 hour) is 100 nm or less, or is in an amorphous phase.
[0017]
By making Si amorphous with P, Sb or B, volume expansion of the solid phase A due to the reaction between silicon and lithium can be suppressed. Further, by doping P, Sb or B into Si (hereinafter, P, Sb and B are also referred to as doping elements), the solid phase A is made amorphous by a solid phase reaction such as a mechanical alloying method. The time required for this can be shortened. As a result, it is possible to prevent the solid phase B from becoming amorphous at the stage of producing composite particles composed of the solid phase A and the solid phase B.
[0018]
By forming the coating layer made of the solid phase B on part or all of the surface of the core particle made of the solid phase A, the pulverization of the core particles is suppressed and the electron conductivity of the negative electrode material is improved. The reason why the solid phase B must be a crystalline alloy phase is that if it is an amorphous phase with many crystal grain boundaries, cracks are generated, the electron conductivity is lowered, and the high rate discharge characteristics are lowered. .
[0019]
The Si content of the solid phase A is preferably 95 to 99.999% by weight, and more preferably 98 to 99.99% by weight. When the Si content of the solid phase A is less than 95% by weight, that is, when the content of the doping element exceeds 5% by weight, the capacity of the obtained negative electrode material decreases. Further, even if the doping element is doped more than 5% by weight, the time required for making the solid phase A amorphous is hardly shortened. On the other hand, when the Si content of the solid phase A exceeds 99.999% by weight, that is, when the content of the dope element is less than 0.001% by weight, the non-solid phase A is not produced in the production process by solid phase reaction. Since crystallization hardly proceeds, not only a long time is required to obtain the negative electrode material, but also the solid phase B may become amorphous.
[0020]
As the solid phase B, in order to improve the high rate discharge characteristics, a crystalline alloy phase of Si and Ti having high electron conductivity is preferable. 2 An intermetallic compound phase represented by is particularly preferred. Particles made of a crystalline alloy phase of Si and Ti also have a manufacturing advantage that it is easy to form composite particles with core particles made of solid phase A by a solid phase reaction.
When the solid phase B is a solid solution, the binary alloy preferably has a weight ratio of Si to the alloying element M1 of 10:90 to 40:60, and the ternary alloy is alloyed with Si. The weight ratio of the element M1 and the alloying element M2 is preferably 10:90 (the weight ratio of M1 and M2 is arbitrary) to 40:60 (the weight ratio of M1 and M2 is arbitrary).
[0021]
The weight ratio between the core particles and the coating layer is preferably 5:95 to 40:60. When the ratio of the core particles is too small, the initial discharge capacity decreases. On the other hand, when the ratio of the coating layer is too small, the coating of the core particles is not sufficient, so that the expansion of the solid phase A due to the reaction between Si and Li cannot be effectively suppressed, and the charge / discharge cycle characteristics are deteriorated. Furthermore, the high-rate discharge characteristics are also reduced due to the decrease in electron conductivity.
[0022]
In addition, as long as it is an amount of 0.001% by weight or less for the solid phase A and 0.1% by weight or less for the solid phase B, elements other than the above-described constituent elements, for example, O, C, Impurities such as N, S, Ca, Mg, and Al may be included.
[0023]
Below, the manufacturing method of the negative electrode material of this invention is demonstrated.
First, each element constituting the solid phase A is heated and melted at a predetermined ratio in a melting tank to obtain a molten alloy, and the molten alloy is rapidly solidified to produce a first alloy lump. In addition, each element constituting the solid phase B is heated and melted in a melting tank at a predetermined ratio to obtain a molten alloy, and the molten alloy is rapidly solidified to produce a second alloy lump. Each constituent element to be melted when each molten alloy is obtained may be put into the melting tank in the form of a simple substance, or may be put into the melting tank in the form of an alloy such as a solid solution or an intermetallic compound. As a melting method, a conventionally known method such as a high frequency melting method or an arc melting method can be used. In addition, as a method of rapid solidification, a conventionally known method such as a roll spinning method, a melt drag method, a direct casting rolling method, or the like can be used.
[0024]
Next, the first alloy lump and the second alloy lump are mechanically stirred and mixed using a ball mill to perform so-called mechanical alloying to produce alloy powder. By performing this mechanical alloying for an appropriate period of time, a coating layer made of the solid phase B that is the crystalline alloy phase can be formed on the surface of the core particle made of the solid phase A that is the amorphous alloy phase. .
[0025]
The negative electrode for a non-aqueous electrolyte secondary battery according to the present invention is an electrode using the negative electrode material described above as a material that absorbs and releases lithium ions. For example, the negative electrode material of the present invention is kneaded with a conductive agent and a binder solution to prepare a slurry-like negative electrode mixture, and the negative electrode mixture is made from a copper foil having a thickness of about 1 to 500 μm. A negative electrode plate can be produced by applying the coating onto the substrate, drying it, and rolling it. Instead of the above-mentioned negative electrode mixture, a slurry-like negative electrode mixture obtained by kneading this and a binder solution after forming a conductive agent layer on the particle surface of the negative electrode material of the present invention may be used. . Examples of the conductive agent include graphite such as artificial graphite and expanded graphite, and amorphous carbon such as acetylene black and ketjen black. The general addition amount of the conductive agent is 1 to 50 parts by weight with respect to 100 parts by weight of the negative electrode material. However, when the addition amount of the conductive agent is excessive, the capacity decrease becomes significant. It is preferable not to exceed 30 parts by weight with respect to 100 parts by weight. Examples of the binder include styrene butadiene rubber and polyvinylidene fluoride. Examples of the current collector material include stainless steel, nickel, copper, and copper alloy. Of these, copper and copper alloys having very good electronic conductivity are preferred.
[0026]
【Example】
The present invention will be described in more detail based on examples. The present invention is not limited to the following examples, and can be implemented with appropriate modifications without departing from the scope of the invention.
[0027]
[Experiment 1]
A negative electrode material of the present invention and a negative electrode material for comparison were prepared, and the crystal state and powder resistivity of the solid phase A of each negative electrode material were examined. Moreover, a non-aqueous electrolyte secondary battery was produced using each negative electrode material, and the high rate discharge characteristics and charge / discharge cycle characteristics of each battery were examined.
[0028]
Example 1
As the solid phase A, Si and P were used, and these were used as a mixture having a weight ratio of 19.9: 0.1. This mixture was put into a high-frequency melting tank to be melted, and the obtained molten alloy was rapidly cooled and solidified by a single roll method to obtain a first alloy lump that is a precursor of core particles.
Moreover, Co and Si were used for the solid phase B, and these were used as a mixture having an atomic ratio of 1: 2. This mixture is put into a high-frequency melting tank to be melted, and the obtained molten alloy is rapidly solidified by a single roll method to obtain a composition formula CoSi. 2 The 2nd alloy lump which is a precursor of the coating layer which consists of intermetallic compounds represented by these was obtained.
Next, a mixture obtained by mixing the first alloy lump and the second alloy lump at a weight ratio of 20:80 is put into a container of a planetary ball mill, the rotational speed of the mill is set to 2800 rpm, and mechanical alloying is performed at 1 Went for hours. As a result, a composite particle powder having a coating layer formed on the surface of the core particle was obtained. The composite particle powder was classified with a sieve to prepare a negative electrode material A1 having an average particle diameter of 45 μm.
[0029]
<< Examples 2-88 >>
A first alloy lump was produced in the same manner as in Example 1 except that the type of the doping element mixed with Si and the weight ratio of Si to the doping element were changed as shown in Table 1 or 2.
As the solid phase B, a second alloy lump made of an intermetallic compound or a solid solution shown in Table 1 or 2 was used.
Next, a mixture obtained by mixing the first alloy lump and the second alloy lump at a weight ratio of 20:80 is put into a container of a planetary ball mill, the rotational speed of the mill is set to 2800 rpm, and mechanical alloying is performed. It went for 1 hour. As a result, a composite particle powder in which a coating layer composed of an intermetallic compound phase or a solid solution phase was formed on the surface of the core particle was obtained. The composite particle powder was classified with a sieve to prepare negative electrode materials A2 to A88 having an average particle diameter of 45 μm.
In addition, for the negative electrode materials A45 to A88 in which the solid phase B forming the coating layer is a solid solution, the atomic ratio between Si and the alloying element M1 is 99 for the binary alloy in producing the second alloy lump. 1 was used, and for the ternary alloy, a mixture in which the atomic ratio of Si, alloying element M1, and alloying element M2 was 99: 0.5: 0.5 was used.
[0030]
[Table 1]
[0031]
[Table 2]
[0032]
<< Comparative Example 1 >>
A composite particle powder in which a coating layer was formed on the surface of the core particle was obtained in the same manner as in Example 1 except that the mechanical alloying time was changed to 30 minutes instead of 1 hour. The composite particle powder was classified with a sieve to produce a negative electrode material X1 having an average particle diameter of 45 μm.
[0033]
<< Comparative Examples 2-22 >>
As the second alloy mass, the composition formula CoSi 2 In the same manner as in Comparative Example 1 except that an alloy lump composed of an intermetallic compound of solid phase B shown in Table 3 or a solid solution was used instead of the alloy lump composed of an intermetallic compound represented by A composite particle powder having a coating layer made of an intermetallic compound or solid solution formed on the surface was obtained. Each composite particle powder was classified with a sieve to prepare negative electrode materials X2 to X22 having an average particle diameter of 45 μm. For the negative electrode materials X12 to X22 in which the solid phase B forming the coating layer is a solid solution, the atomic ratio between Si and the alloying element M1 is 99: 1 in producing the second alloy mass as a binary alloy. A mixture of was used.
[0034]
[Table 3]
[0035]
(I) Preparation of positive electrode plate
Lithium cobaltate (LiCoO) as positive electrode active material 2 ) A mixture of 85 parts by weight of powder, 10 parts by weight of acetylene black as a conductive agent, and 5 parts by weight of PVdF (polyvinylidene fluoride) as a binder is dispersed in NMP (dehydrated N-methyl-2-pyrrolidone). Thus, a slurry-like positive electrode mixture was prepared. This positive electrode mixture was applied onto a positive electrode current collector made of an aluminum foil having a thickness of 20 μm so as to have a thickness of 150 μm per side, dried and rolled to produce a positive electrode plate.
[0036]
(Ii) Production of negative electrode plate
A mixture of 75 parts by weight of each negative electrode material prepared in the above examples or comparative examples, 20 parts by weight of acetylene black as a conductive agent, and 5 parts by weight of PVdF as a binder is dispersed in NMP to form a slurry. A negative electrode mixture was prepared. This negative electrode mixture was applied to a negative electrode current collector made of a copper foil having a thickness of 14 μm so as to have a thickness of 50 μm per side, dried and rolled to prepare a negative electrode plate.
[0037]
(Iii) Preparation of non-aqueous electrolyte
In a mixed solvent of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) in a volume ratio of 1: 1, LiPF 6 Was dissolved at a concentration of 1 mol / liter to prepare a non-aqueous electrolyte.
[0038]
(Iv) Fabrication of non-aqueous electrolyte secondary battery
Cylindrical nonaqueous electrolyte secondary batteries A1 to A88, X1 to X22 having a diameter of 18 mm and a height of 65 mm using the positive electrode plate, the negative electrode plate, and the nonaqueous electrolyte solution (the symbols of the batteries are the same as those of the negative electrode material used). Corresponding to the code). As the separator, a microporous film made of polyethylene was used.
[0039]
FIG. 2 is a longitudinal sectional view of the produced nonaqueous electrolyte secondary battery, and a part of its internal structure is shown in an exploded perspective view. The nonaqueous electrolyte secondary battery includes a positive electrode 1, a negative electrode 2, a separator 3 that separates both electrodes, an insulating plate 4, a battery case 5, a gasket 7, a sealing plate 8 having a safety valve, a positive electrode lead 6, and the like. The positive electrode 1 and the negative electrode 2 are accommodated in the battery case 5 with the separator 3 interposed therebetween and wound in a spiral shape. The positive electrode 1 is connected to the sealing plate 8 via the positive electrode lead 6 and the negative electrode 2. Are connected to the bottom of the battery case 5 via a negative electrode lead (not shown), respectively, so that they can be charged and discharged.
[0040]
[Crystal state of solid phase A]
In order to evaluate the crystalline state of the solid phase A in each negative electrode material, a wide-angle X-ray diffractometer (product code: RINT-2500, manufactured by Rigaku Corporation) using a CuKα ray having a wavelength of 1.5405 nm as a radiation source was used. The diffraction intensity in the range of diffraction angle 2θ = 10 ° to 80 ° was measured. The presence or absence of a peak attributed to the crystal plane of the solid phase A was examined. The results are shown in Tables 4-6. In the presence or absence of a peak in the table, “None” indicates that there is no peak attributed to the crystal plane of the solid phase A, indicating that the solid phase A was an amorphous phase, and “Yes” indicates that the above peak is present. Present, indicating that solid phase A was a crystalline phase. As an example, the diffraction patterns of the negative electrode materials A3 and X3 are shown in FIG.
In FIG. 1, the horizontal axis represents the diffraction angle 2θ (degrees) of the solid phase A and the solid phase B, and the vertical axis represents the diffraction intensity. In the figure, ◎ indicates a peak attributed to the crystal plane of the solid phase A, and ● indicates a peak attributed to the crystal plane of the solid phase B.
[0041]
[Powder resistivity]
2 g of each negative electrode material was weighed and put into a cell having a total of four measurement points of two current terminals and two voltage terminals, and 400 kgf / cm 2 In the state where the pressure was applied, the current and voltage were measured simultaneously to measure the powder resistivity (Ω · cm) of each negative electrode material (4-terminal method). A negative electrode material having a lower powder resistivity is a negative electrode material having better electron conductivity. The results are shown in Tables 4-6.
[0042]
[Initial discharge capacity and high rate discharge characteristics]
Each battery was put in a thermostat kept at 20 ° C., charged to 4.2 V at 1000 mA, and then discharged to 2.5 V at 200 mA to obtain a discharge capacity C1 (mAh) (initial discharge capacity). Next, each of these batteries was charged at 1000 mA to 4.2 V, and then discharged at 1000 mA to 2.5 V to obtain a discharge capacity C2 (mAh). The ratio P (%) of the discharge capacity C2 to the discharge capacity C1 was calculated based on the following formula (1) to evaluate the high rate discharge characteristics P of each battery. A battery having a larger value of P is a battery having better high rate discharge characteristics. The results are shown in Tables 4-6.
[0043]
P (%) = (C2 / C1) × 100 (1)
[0044]
[Charge / discharge cycle characteristics]
Each battery was placed in a thermostat kept at 20 ° C., charged at 1000 mA to 4.2 V, and then charged and discharged at 200 mA to 2.5 V for 100 cycles. Then, the capacity maintenance rate Q (%) of the discharge capacity C4 of the 100th cycle with respect to the discharge capacity C3 of the first cycle was calculated based on the following formula (2), and the charge / discharge cycle characteristics Q were evaluated. A battery having a larger Q value has better charge / discharge cycle characteristics. The results are shown in Tables 4-6.
[0045]
Q (%) = (C4 / C3) × 100 (2)
[0046]
[Table 4]
[0047]
[Table 5]
[0048]
[Table 6]
[0049]
(V) Battery evaluation
As shown in Tables 4-6, the negative electrode materials A1-A88 have a powder resistivity of 1 × 10 -1 ~ 9x10 -1 While the low value of Ω · cm was obtained, the powder resistivity of the negative electrode materials X1 to X22 was 5 × 10 0 ~ 9.5 × 10 0 The value was as high as Ω · cm. From this, it was found that the negative electrode materials A1 to A88 had better electron conductivity than the negative electrode materials X1 to X22.
[0050]
Further, as seen in the diffraction pattern of the negative electrode material X3 in FIG. 1, for the negative electrode materials X1 to X22 of the comparative example, near the diffraction angles (2θ = 28 ° and 48 °) attributed to the crystal plane of the solid phase A However, as can be seen in the diffraction pattern of the negative electrode material A3, no peak was observed in the vicinity of the diffraction angles of the negative electrode materials A1 to A88 of the example. From this, it was found that the solid phase A of the negative electrode materials A1 to A88 is an amorphous phase, whereas the solid phase A of the negative electrode materials X1 to X22 is a crystalline phase. Further, FIG. 1 also shows that the solid phase B of the negative electrode material A3 and the solid phase B of the negative electrode material X3 have the same degree of crystallinity.
[0051]
Further, as shown in Tables 4 to 6, since the value of the high rate discharge characteristic P of the batteries A1 to A88 is as large as 90% or more, the use of these negative electrode materials makes it possible to obtain a non-aqueous electrolyte with good high rate discharge characteristics. It turns out that the next battery is obtained.
[0052]
Furthermore, as shown in Tables 4 to 6, the values of the charge / discharge cycle characteristics Q of the batteries A1 to A88 are 90% or more, and the values of the charge / discharge cycle characteristics Q of the batteries X1 to X22 are 78% or less. Thus, it was found that by using the negative electrode materials A1 to A88, a nonaqueous electrolyte secondary battery having good charge / discharge cycle characteristics was obtained.
[0053]
[Experiment 2]
The relationship between the Si content of the solid phase A and the high rate discharge characteristics was investigated.
In the production of the first alloy lump, instead of the mixture of Si and P having a weight ratio of 19.9: 0.1, a mixture having each Si content of solid phase A shown in Table 7 was used. A composite particle powder having a coating layer formed on the surface of the core particle was obtained in the same manner as in Example 1 except that the weight ratio of the alloy lump and the second alloy lump was 21:79. Each of these composite particle powders was classified with a sieve to prepare negative electrode materials B1 to B13 having an average particle diameter of 45 μm.
[0054]
[Table 7]
[0055]
Further, in the production of the first alloy lump, instead of a mixture of Si and P in a weight ratio of 19.9: 0.1, a mixture having each Si content of solid phase A shown in Table 8 was used, A composite particle powder having a coating layer formed on the surface of the core particle was obtained in the same manner as in Example 45 except that the weight ratio of the first alloy lump to the second alloy lump was 21:79. . Each of these composite particle powders was classified with a sieve to prepare negative electrode materials B14 to B26 having an average particle diameter of 45 μm.
[0056]
[Table 8]
[0057]
The crystal state and powder resistivity of the solid phase A of each of the negative electrode materials (B1 to B26) were examined. In addition, a non-aqueous electrolyte secondary battery was produced using each of the negative electrode materials, and the high rate discharge characteristics and charge / discharge cycle characteristics of each battery were examined. The results are shown in Tables 9 and 10.
[0058]
[Table 9]
[0059]
[Table 10]
[0060]
In any of the diffraction patterns of the negative electrode materials B1 to B26, no peak attributed to the crystal plane of the solid phase A was observed. From this, it was found that those solid phases A were all amorphous phases. Further, from Tables 9 and 10, it was found that, as the Si content of the solid phase A decreases, the high rate discharge characteristic P improves, but the initial discharge capacity decreases. Considering the characteristic balance between the initial discharge capacity and the high rate discharge characteristics, the batteries B4 to B11 and the batteries B17 to B24 were particularly excellent. From this, it was found that the Si content of the solid phase A is preferably 95 to 99.999% by weight. Although not shown in Tables 9 and 10, the capacity maintenance rates Q of the batteries B1 to B26 were 86% to 93%.
[0061]
[Experiment 3]
The relationship between the weight ratio between the core particles and the coating layer and the high rate discharge characteristics was investigated.
A composite particle in which a coating layer is formed on the surface of the base particle in the same manner as in Example 2 except that the weight ratio of the first alloy lump to the second alloy lump was changed to the weight ratio shown in Table 11. A powder was obtained. These composite particle powders were classified with a sieve to prepare negative electrode materials D1 to D10 having an average particle diameter of 45 μm.
[0062]
[Table 11]
[0063]
Further, a coating layer was formed on the surface of the base particle in the same manner as in Example 46 except that the weight ratio of the first alloy lump and the second alloy lump was changed to the weight ratio shown in Table 12. A composite particle powder was obtained. These composite particle powders were classified with a sieve to prepare negative electrode materials D11 to D19 having an average particle diameter of 45 μm.
[0064]
[Table 12]
[0065]
The crystal state and powder resistivity of the solid phase A of each of the negative electrode materials D1 to D19 were examined. Moreover, a non-aqueous electrolyte secondary battery was produced using each negative electrode material, and the high rate discharge characteristics and charge / discharge cycle characteristics of each battery were examined. The results are shown in Tables 13 and 14.
[0066]
[Table 13]
[0067]
[Table 14]
[0068]
No peak attributed to the crystal plane of the solid phase A was observed in any of the diffraction patterns of the negative electrode materials D1 to D19. From this, it was found that those solid phases A were all amorphous phases. Further, from Tables 13 and 14, it was found that, as the ratio of the coating layer to the core particles increases, the high rate discharge characteristic P improves, but the initial discharge capacity decreases. In consideration of the balance between the initial discharge capacity and the high rate discharge characteristics, the batteries D3 to D7 and the batteries D12 to D16 were particularly excellent. From this, it was found that the weight ratio of the base particles to the coating layer is preferably 5:95 to 40:60. Although not shown in Tables 13 and 14, the capacity maintenance rates Q of the batteries D1 to D19 were 86% to 93%.
[0069]
[Experiment 4]
The relationship between the type of solid phase B and high rate discharge characteristics was investigated.
In the same manner as in Example 1, a first alloy lump was obtained. A mixture of the first alloy lump and the second alloy lump of solid phase B shown in Table 15 in a weight ratio of 22:78 was put into a container of a planetary ball mill, and the rotation speed of the mill was set to 2800 rpm. Mechanical alloying was performed for 1 hour to obtain a composite particle powder in which a coating layer composed of an intermetallic compound phase was formed on the surface of the core particle. These composite particle powders were classified with a sieve to prepare negative electrode materials E1 to E11 having an average particle diameter of 45 μm.
[0070]
[Table 15]
[0071]
In the same manner as in Example 45, a first alloy ingot was obtained. A mixture of the first alloy lump and the second alloy lump of solid phase B shown in Table 16 in a weight ratio of 22:78 was put into a container of a planetary ball mill, and the rotation speed of the mill was set to 2800 rpm. Mechanical alloying was performed for 1 hour to obtain a composite particle powder in which a coating layer composed of a solid solution phase was formed on the surface of the core particle. These composite particle powders were classified with a sieve to prepare negative electrode materials E12 to E22 having an average particle diameter of 45 μm.
[0072]
[Table 16]
[0073]
The crystal state of the solid phase A and the powder resistivity of each negative electrode material were examined. Moreover, a non-aqueous electrolyte secondary battery was produced using each negative electrode material, and the high rate discharge characteristics and charge / discharge cycle characteristics of each battery were examined. The results are shown in Tables 17 and 18.
[0074]
[Table 17]
[0075]
[Table 18]
[0076]
No peak attributed to the crystal plane of the solid phase A was observed in any diffraction pattern of the negative electrode materials E1 to E22. From this, it was found that these solid phases A were all amorphous. Further, as shown in Tables 17 and 18, the initial discharge capacities of the batteries E8 and E19 were particularly large, and the value of the high rate discharge characteristic was particularly good. From this, when the solid phase B is a crystalline alloy phase of Ti and Si, the solid phase B particularly has the composition formula TiSi. 2 It was found that a non-aqueous electrolyte secondary battery having a very good high rate discharge characteristic and a large initial discharge capacity can be obtained when the intermetallic compound phase represented by Although not shown in Tables 17 and 18, the capacity maintenance rates Q of the batteries E1 to E22 were 86% to 93%.
[0077]
In the above embodiment, the case where the negative electrode material is used as the negative electrode material of the cylindrical non-aqueous electrolyte secondary battery is described. However, the negative electrode material of the present invention is not only cylindrical but also coin type, button type, sheet type, laminated type In addition, it can be used as a negative electrode material for non-aqueous electrolyte secondary batteries having various shapes such as flat type and square type.
[0078]
【The invention's effect】
According to the present invention, a coating layer containing Si and a metal element is formed on part or all of the surface of a core particle containing Si and at least one selected from the group consisting of Sb and P or B. By preparing a negative electrode material for a non-aqueous electrolyte secondary battery composed of the composite particles and providing it in a non-aqueous electrolyte secondary battery, it is possible to have excellent charge / discharge cycle characteristics and high rate discharge characteristics.
[Brief description of the drawings]
FIG. 1 is a pattern diagram by X-ray diffraction of negative electrode materials prepared in Examples and Comparative Examples.
FIG. 2 is a longitudinal sectional view of a cylindrical non-aqueous electrolyte secondary battery manufactured in an example, showing a part of its internal structure in an exploded perspective view.
[Explanation of symbols]
1 Positive electrode
2 Negative electrode
3 Separator
4 Insulation plate
5 Battery case
6 Positive lead
7 Gasket
8 Sealing plate

Claims (6)

  1. A negative electrode material for a non-aqueous electrolyte secondary battery comprising composite particles in which a coating layer comprising a solid phase B is formed on part or all of the surface of a core particle comprising a solid phase A,
    The solid phase A is an amorphous alloy phase containing Si and at least one selected from the group consisting of Sb and P or B,
    Solid Phase B, Si and, Mg, Ti, Zr, V , Mo, W, Mn, Ri crystalline alloy phase der containing at least one kind Fe, Cu, selected from the group consisting of Co and Ni,
    The Si content of the solid phase A is 95-99.99 wt%,
    A negative electrode material for a non-aqueous electrolyte secondary battery, wherein the total content of Sb, P and B in the solid phase A is 0.01 to 5% by weight .
  2. 2. The negative electrode material for a non-aqueous electrolyte secondary battery according to claim 1, wherein a weight ratio of the core particles to the coating layer is 5:95 to 40:60.
  3. The solid phase B is a negative electrode material for a non-aqueous electrolyte secondary battery according to claim 1 or 2 , comprising a crystalline alloy phase of Si and Ti.
  4. The negative electrode material for a nonaqueous electrolyte secondary battery according to claim 3, wherein the crystalline alloy phase of Si and Ti is an intermetallic compound phase represented by a composition formula TiSi 2 .
  5. A negative electrode for a non-aqueous electrolyte secondary battery comprising the negative electrode material for a non-aqueous electrolyte secondary battery according to any one of claims 1 to 4 as a material that absorbs and releases lithium ions.
  6. A nonaqueous electrolyte secondary battery comprising: a negative electrode for a nonaqueous electrolyte secondary battery according to claim 5; a positive electrode capable of inserting and extracting lithium; a separator interposed between the negative electrode and the positive electrode; and a nonaqueous electrolyte. battery.
JP2003129705A 2003-05-08 2003-05-08 Anode material for non-aqueous electrolyte secondary battery Expired - Fee Related JP4368139B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2003129705A JP4368139B2 (en) 2003-05-08 2003-05-08 Anode material for non-aqueous electrolyte secondary battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2003129705A JP4368139B2 (en) 2003-05-08 2003-05-08 Anode material for non-aqueous electrolyte secondary battery

Publications (2)

Publication Number Publication Date
JP2004335272A JP2004335272A (en) 2004-11-25
JP4368139B2 true JP4368139B2 (en) 2009-11-18

Family

ID=33505427

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2003129705A Expired - Fee Related JP4368139B2 (en) 2003-05-08 2003-05-08 Anode material for non-aqueous electrolyte secondary battery

Country Status (1)

Country Link
JP (1) JP4368139B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103201060A (en) * 2010-11-08 2013-07-10 古河电气工业株式会社 Nanoscale particles used in negative electrode for lithium ion secondary battery and method for manufacturing same
KR101520557B1 (en) * 2010-11-08 2015-05-14 후루카와 덴키 고교 가부시키가이샤 Non-aqueous electrolyte secondary battery

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5030414B2 (en) * 2004-11-15 2012-09-19 パナソニック株式会社 Nonaqueous electrolyte secondary battery
US7955735B2 (en) 2004-11-15 2011-06-07 Panasonic Corporation Non-aqueous electrolyte secondary battery
JP4984402B2 (en) * 2005-02-28 2012-07-25 パナソニック株式会社 Nonaqueous electrolyte secondary battery
CN100533821C (en) * 2005-06-03 2009-08-26 松下电器产业株式会社 Rechargeable battery with nonaqueous electrolyte and process for producing negative electrode
EP1946403B1 (en) * 2005-10-13 2012-04-25 3M Innovative Properties Company Method of using an electrochemical cell
US7662514B2 (en) 2005-11-17 2010-02-16 Panasonic Corporation Non-aqueous electrolyte secondary battery and method for producing negative electrode material for non-aqueous electrolyte secondary battery
JP5061458B2 (en) 2005-12-19 2012-10-31 パナソニック株式会社 Anode material for non-aqueous electrolyte secondary battery and method for producing the same
US8426065B2 (en) 2008-12-30 2013-04-23 Lg Chem, Ltd. Anode active material for secondary battery
JP2012102354A (en) * 2010-11-08 2012-05-31 Furukawa Battery Co Ltd:The Nano-size particle, negative electrode material for lithium ion secondary battery including the nano-size particle, negative electrode for lithium ion secondary battery, lithium ion secondary battery, and method for producing the nano-size particle
JP2012101958A (en) * 2010-11-08 2012-05-31 Furukawa Battery Co Ltd:The Nanoscale particle, negative electrode material for lithium ion secondary battery containing the same, negative electrode for lithium ion secondary battery, lithium ion secondary battery, method for producing the nanoscale particle
JP5656570B2 (en) * 2010-11-08 2015-01-21 古河電気工業株式会社 Method for producing negative electrode material for lithium ion secondary battery, negative electrode for lithium ion secondary battery, lithium ion secondary battery, negative electrode material for lithium ion secondary battery
KR101718058B1 (en) 2012-08-01 2017-03-20 삼성에스디아이 주식회사 Negative active material, preparing method thereof, and lithium battery employing the same
KR101739297B1 (en) 2012-11-27 2017-05-24 삼성에스디아이 주식회사 Anode active material, lithium secondary battery employing the same, and preparing method thereof
KR20150006703A (en) * 2013-07-09 2015-01-19 삼성정밀화학 주식회사 Negative active material for rechargeabl lithium battery, composition for negative electrode including the same, and rechargeabl lithium battery
JP6318859B2 (en) * 2014-05-29 2018-05-09 株式会社豊田自動織機 Copper-containing silicon material, manufacturing method thereof, negative electrode active material, and secondary battery
WO2016098215A1 (en) * 2014-12-17 2016-06-23 日産自動車株式会社 Electrical device
JP6380554B2 (en) * 2014-12-17 2018-08-29 日産自動車株式会社 Electrical device
JP2016225143A (en) * 2015-05-29 2016-12-28 エルジー・ケム・リミテッド Negative electrode material for secondary battery and nonaqueous electrolyte secondary battery using the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103201060A (en) * 2010-11-08 2013-07-10 古河电气工业株式会社 Nanoscale particles used in negative electrode for lithium ion secondary battery and method for manufacturing same
KR101520557B1 (en) * 2010-11-08 2015-05-14 후루카와 덴키 고교 가부시키가이샤 Non-aqueous electrolyte secondary battery

Also Published As

Publication number Publication date
JP2004335272A (en) 2004-11-25

Similar Documents

Publication Publication Date Title
JP3524762B2 (en) Lithium secondary battery
KR100458098B1 (en) Electrode Material for Negative Pole of Lithium Secondary Cell, Electrode Structure Using Said Electrode Material, Lithium Secondary Cell Using Said Electrode Structure, and Method for Manufacturing Said Electrode Structure and Said Lithium Secondary Cell
US8673490B2 (en) High energy lithium ion batteries with particular negative electrode compositions
JP3997702B2 (en) Nonaqueous electrolyte secondary battery
CN100382362C (en) Electrode material for lithium secondary battery and electrode structure having the electrode material
JP3010226B2 (en) A nonaqueous electrolyte secondary battery and a manufacturing method thereof
JP4781955B2 (en) Cathode active material, method for producing the same, and lithium battery employing the same
JP5225615B2 (en) Lithium ion storage battery containing TiO2-B as negative electrode active material
US7635540B2 (en) Negative electrode for non-aqueous electrolyte secondary battery and non-aqueous electrolyte secondary battery comprising the same
KR101120692B1 (en) Multi-phase, silicon-containing electrode for a lithium-ion battery
US9012073B2 (en) Composite compositions, negative electrodes with composite compositions and corresponding batteries
EP1465271A1 (en) Positive plate active material and nonaqueous electrolyte secondary cell using same
US20080241647A1 (en) Cylindrical lithium secondary battery
US20040062990A1 (en) Negative electrode material for non-aqueous electrolyte secondary battery, method for producing the same and non-aqueous electrodlyte secondary battery
US8906557B2 (en) Anode active material and method of preparing the same
US20060046144A1 (en) Anode composition for lithium ion battery
KR20010032228A (en) Electrode Material for Negative Pole of Lithium Secondary Cell, Electrode Structure Using Said Electrode Material, Lithium Secondary Cell Using Said Electrode Structure, and Method for Manufacturing Said Electrode Structure and Said Lithium Secondary Cell
JP3805053B2 (en) lithium secondary battery
US8003253B2 (en) Non-aqueous electrolyte secondary battery
KR100435180B1 (en) Negative electrode material for non-aqueous electrolyte secondary cell, negative electrode, non-aqueous electrolyte secondary cell, and method of producing the material
JP3726958B2 (en) battery
US20020076613A1 (en) Method for surface treatment of layered structure oxide for positive electrode in lithium secondary battery
KR101587293B1 (en) Li-Ni-BASED COMPOSITE OXIDE PARTICLE POWDER FOR RECHARGEABLE BATTERY WITH NONAQUEOUS ELECTROLYTE, PROCESS FOR PRODUCING THE POWDER, AND RECHARGEABLE BATTERY WITH NONAQUEOUS ELECTROLYTE
JP3846661B2 (en) Lithium secondary battery
JP2009032644A (en) Negative electrode active material for lithium secondary battery, and lithium secondary battery

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20060308

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20090410

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20090507

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20090706

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20090730

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: 20090825

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: 20120904

Year of fee payment: 3

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

Free format text: PAYMENT UNTIL: 20120904

Year of fee payment: 3

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313115

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

Free format text: PAYMENT UNTIL: 20120904

Year of fee payment: 3

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

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

Free format text: PAYMENT UNTIL: 20120904

Year of fee payment: 3

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

Free format text: PAYMENT UNTIL: 20130904

Year of fee payment: 4

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

S531 Written request for registration of change of domicile

Free format text: JAPANESE INTERMEDIATE CODE: R313531

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313115

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

LAPS Cancellation because of no payment of annual fees