JP2007165079A - Negative electrode for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery using it - Google Patents

Negative electrode for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery using it Download PDF

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JP2007165079A
JP2007165079A JP2005358755A JP2005358755A JP2007165079A JP 2007165079 A JP2007165079 A JP 2007165079A JP 2005358755 A JP2005358755 A JP 2005358755A JP 2005358755 A JP2005358755 A JP 2005358755A JP 2007165079 A JP2007165079 A JP 2007165079A
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negative electrode
silicon
containing particles
electrolyte secondary
expansion
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Kokukiyo Kashiwagi
克巨 柏木
Takayuki Shirane
隆行 白根
Kaoru Inoue
薫 井上
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Panasonic Holdings Corp
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Matsushita Electric Industrial Co Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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    • Y02E60/10—Energy storage using batteries

Abstract

<P>PROBLEM TO BE SOLVED: To provide a negative electrode having excellent cycle characteristics by suppressing increase in impedance of the whole negative electrode using silicon-containing particles capable of charging and discharging at least lithium ions as an active material, and to provide a battery using the negative electrode. <P>SOLUTION: The negative electrode for a nonaqueous electrolyte secondary battery has a composite negative active material 13 comprising silicon-containing particles 11 capable of absorbing/releasing at least lithium ions and carbon nano-fibers 12; and a mix layer containing an expansion/contraction buffer material 14 having conductivity. The carbon nano-fibers 12 are bonded to the surface of the silicon-containing particles 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は非水電解質二次電池用負極に関し、より詳しくはリチウムイオンを高密度に吸蔵放出する含ケイ素粒子を活物質として用いる負極の充放電サイクル特性を改善する技術に関する。   The present invention relates to a negative electrode for a non-aqueous electrolyte secondary battery, and more particularly to a technique for improving charge / discharge cycle characteristics of a negative electrode using silicon-containing particles that store and release lithium ions at high density as an active material.

電子機器のポータブル化、コードレス化が進むにつれて、小型・軽量で、かつ高エネルギー密度を有する非水電解質二次電池への期待は高まりつつある。現在、黒鉛などの炭素材料が非水電解質二次電池の負極活物質として実用化されている。しかしながらその理論容量密度は３７２ｍＡｈ／ｇである。そこで、さらに非水電解質二次電池を高エネルギー密度化するために、リチウムと合金化するケイ素（Ｓｉ）、スズ（Ｓｎ）、ゲルマニウム（Ｇｅ）やこれらの酸化物および合金などが検討されている。これらの負極活物質材料の理論容量密度は、炭素材料に比べて大きい。特にＳｉ粒子や酸化ケイ素粒子などの含ケイ素粒子は安価なため、幅広く検討されている。   As electronic devices become more portable and cordless, expectations for non-aqueous electrolyte secondary batteries that are small and lightweight and have high energy density are increasing. Currently, carbon materials such as graphite are put into practical use as negative electrode active materials for non-aqueous electrolyte secondary batteries. However, its theoretical capacity density is 372 mAh / g. Therefore, silicon (Si), tin (Sn), germanium (Ge), and oxides and alloys thereof, which are alloyed with lithium, are being studied in order to further increase the energy density of nonaqueous electrolyte secondary batteries. . The theoretical capacity density of these negative electrode active material materials is larger than that of carbon materials. In particular, silicon-containing particles such as Si particles and silicon oxide particles are widely studied because they are inexpensive.

しかしながら、これらの材料を負極活物質に用いて充放電サイクルを繰り返すと、充放電に伴う活物質粒子の体積変化が起こる。この体積変化により活物質粒子は微紛化し、その結果、活物質粒子間の導電性が低下する。そのため、十分な充放電サイクル特性（以下、「サイクル特性」という）が得られない。   However, when these materials are used as the negative electrode active material and the charge / discharge cycle is repeated, the volume of the active material particles changes due to charge / discharge. This volume change makes the active material particles fine, and as a result, the conductivity between the active material particles decreases. Therefore, sufficient charge / discharge cycle characteristics (hereinafter referred to as “cycle characteristics”) cannot be obtained.

そこでリチウム合金を形成しうる金属または半金属を含む活物質粒子を核に、複数の炭素繊維を結合させて複合粒子化させることが提案されている。この構成では、活物質粒子の体積変化が起こっても導電性が確保され、サイクル特性が維持できることが報告されている（例えば、特許文献１）。
特開２００４−３４９０５６号公報 Therefore, it has been proposed to combine a plurality of carbon fibers into a composite particle by using active material particles containing a metal or a semimetal capable of forming a lithium alloy as a core. In this configuration, it has been reported that conductivity is ensured and cycle characteristics can be maintained even if the volume of the active material particles changes (for example, Patent Document 1).
JP 2004-349056 A

しかしながら、含ケイ素粒子からなる核と、その表面に先端が付着された複数の炭素繊維とを備えた複合負極活物質粒子だけで負極合剤層を構成すると、長期にわたる充放電において含ケイ素粒子の著しい膨張収縮のために炭素繊維が外れ、あるいは炭素繊維が切断される。また充電時の含ケイ素粒子の膨張が大きいために、放電しても負極合剤層がもとの形状に戻りにくい。その結果、負極合剤層が不可逆的に変形して膨張する。これらのような現象により、負極合剤層内の導電性が低下して負極全体のインピーダンスが増大する。すなわち、長期にわたり充放電が繰り返されると、電極としての機能を持続させることができなくなり、放電容量をはじめとする電池特性が低下する。   However, when the negative electrode mixture layer is composed only of composite negative electrode active material particles each having a core made of silicon-containing particles and a plurality of carbon fibers having tips attached to the surface thereof, the silicon-containing particles can be charged and discharged over a long period of time. The carbon fiber comes off or the carbon fiber is cut due to significant expansion and contraction. Moreover, since the expansion of the silicon-containing particles during charging is large, the negative electrode mixture layer is unlikely to return to its original shape even when discharged. As a result, the negative electrode mixture layer irreversibly deforms and expands. Due to such a phenomenon, the conductivity in the negative electrode mixture layer is lowered and the impedance of the whole negative electrode is increased. That is, if charging / discharging is repeated over a long period of time, the function as an electrode cannot be maintained, and battery characteristics including discharge capacity are deteriorated.

この現象はコイン型電池より長尺の薄型極板を捲回して構成する円筒型や角型の電池の場合に、より顕著である。すなわち、コイン型電池では負極の変形方向が厚み方向主体であるのに比べて、捲回型の電池では負極の平面の任意の方向で変形が生じ、任意の場所にしわや剥離が生じる。そのため、局所的に集電不良が発生する。結果として充放電サイクルに伴う電池特性の低下が著しい。   This phenomenon is more conspicuous in the case of a cylindrical or rectangular battery that is formed by winding a thin electrode plate that is longer than a coin-type battery. That is, in the coin type battery, the deformation direction of the negative electrode is mainly in the thickness direction, whereas in the wound type battery, the deformation occurs in an arbitrary direction of the negative electrode plane, and wrinkles or peeling occurs in an arbitrary place. Therefore, current collection failure locally occurs. As a result, the deterioration of the battery characteristics accompanying the charge / discharge cycle is remarkable.

本発明は含ケイ素粒子に炭素繊維であるカーボンナノファイバ（ＣＮＦ）を付与した複合負極活物質を用いるとともに、この複合負極活物質の特徴を活用して、サイクル特性に優れた構造を構築し、長期にわたり負極全体のインピーダンス増大を抑制して、優れたサイクル特性を有する非水電解質二次電池用負極およびこれを用いた非水電解質二次電池を提供することを目的とする。   The present invention uses a composite negative electrode active material in which carbon nanofibers (CNF), which are carbon fibers, are added to silicon-containing particles, and utilizes the characteristics of this composite negative electrode active material to construct a structure with excellent cycle characteristics, An object of the present invention is to provide a negative electrode for a non-aqueous electrolyte secondary battery having excellent cycle characteristics by suppressing an increase in impedance of the entire negative electrode over a long period of time and a non-aqueous electrolyte secondary battery using the same.

上記の課題を解決するために本発明の非水電解質二次電池用負極は、少なくともリチウムイオン吸蔵放出が可能な含ケイ素粒子と、含ケイ素粒子の表面に付着（固着）されたカーボンナノファイバ（ＣＮＦ）とからなる複合負極活物質と、導電性を有する膨張収縮緩衝材とを含む合剤層を有する。この構成では導電性に乏しい含ケイ素粒子間にＣＮＦと膨張収縮緩衝材とを介して電子的結合のネットワークが形成されている。そして充電時には膨張収縮緩衝材が変形することにより含ケイ素粒子の膨張による合剤層の膨張を緩和する。また放電時には含ケイ素粒子が収縮するが、ＣＮＦに絡まっている膨張収縮緩衝材が引っ張られて広がるので、放電時の導電性低下も抑制される。   In order to solve the above problems, the negative electrode for a non-aqueous electrolyte secondary battery of the present invention comprises at least silicon-containing particles capable of occluding and releasing lithium ions, and carbon nanofibers attached (fixed) to the surfaces of the silicon-containing particles ( And a composite negative electrode active material composed of CNF) and an expansion / contraction buffer material having conductivity. In this configuration, a network of electronic bonds is formed between the silicon-containing particles having poor conductivity via CNF and the expansion / contraction buffer material. In addition, the expansion and contraction buffer material is deformed during charging, thereby relaxing expansion of the mixture layer due to expansion of the silicon-containing particles. In addition, the silicon-containing particles contract during discharge, but the expansion / contraction buffer material entangled with CNF is pulled and spreads, so that a decrease in conductivity during discharge is also suppressed.

本発明はさらに、上述の複合負極活物質を含む負極を用いた非水電解質二次電池に関する。   The present invention further relates to a non-aqueous electrolyte secondary battery using a negative electrode containing the composite negative electrode active material described above.

本発明によれば、高容量でかつサイクル特性に優れた非水電解質二次電池を提供することができる。   According to the present invention, a non-aqueous electrolyte secondary battery having a high capacity and excellent cycle characteristics can be provided.

第１の発明は、少なくともリチウムイオンの充放電が可能な含ケイ素粒子と、含ケイ素粒子の表面に付着（固着）されたカーボンナノファイバ（ＣＮＦ）とからなる複合負極活物質と、導電性を有する膨張収縮緩衝材とを含む合剤層を有する非水電解質二次電池用負極である。この構成では含ケイ素粒子の表面に、ＣＮＦの一端が固定されているだけでなく、その複合負極活物質の粒子間に導体の膨張収縮緩衝材が存在する。すなわち導電性のＣＮＦの一端は含ケイ素粒子の表面に固着され、他端はこの膨張収縮緩衝材に接続されている。その結果、導電性に乏しい含ケイ素粒子間にはＣＮＦと膨張収縮緩衝材とを介して導電ネットワークが形成されている。そして充電時には複合負極活物質間に介在させた膨張収縮緩衝材が変形することにより含ケイ素粒子の膨張による合剤層の膨張を緩和する。また含ケイ素粒子表面に固着されたＣＮＦが膨張収縮緩衝材に適度に絡まることにより、複合活物質間に膨張収縮緩衝材が均一に存在しやすくなるため、膨張収縮緩衝材の凝集を物理的に抑制できる。また放電時には含ケイ素粒子が収縮するが、ＣＮＦに絡まっている膨張収縮緩衝材が引っ張られて広がるので、放電時の導電性低下も抑制される。このように活物質核である含ケイ素粒子間の導電ネットワークが保たれることにより優れたサイクル特性が得られる。   According to a first aspect of the present invention, there is provided a composite negative electrode active material comprising silicon-containing particles capable of charging / discharging at least lithium ions, and carbon nanofibers (CNF) attached (fixed) to the surfaces of the silicon-containing particles, and conductivity. It is a negative electrode for nonaqueous electrolyte secondary batteries which has the mixture layer containing the expansion-contraction buffer material which has. In this configuration, not only one end of CNF is fixed on the surface of the silicon-containing particles, but also a conductor expansion / contraction buffer material exists between the particles of the composite negative electrode active material. That is, one end of the conductive CNF is fixed to the surface of the silicon-containing particles, and the other end is connected to the expansion / contraction buffer material. As a result, a conductive network is formed between the silicon-containing particles having poor conductivity via the CNF and the expansion / contraction buffer material. Then, the expansion / shrinkage buffering material interposed between the composite negative electrode active materials is deformed during charging, thereby relaxing the expansion of the mixture layer due to the expansion of the silicon-containing particles. Further, since the CNF fixed to the surface of the silicon-containing particles is appropriately entangled with the expansion / shrinkage buffer material, the expansion / shrinkage buffer material tends to exist uniformly between the composite active materials. Can be suppressed. In addition, the silicon-containing particles contract during discharge, but the expansion / contraction buffer material entangled with CNF is pulled and spreads, so that a decrease in conductivity during discharge is also suppressed. Thus, excellent cycle characteristics can be obtained by maintaining a conductive network between silicon-containing particles which are active material nuclei.

第２の発明は、第１の発明において膨張収縮緩衝材がストラクチャ構造を有するカーボンブラック（ＣＢ）である非水電解質二次電池用負極である。ストラクチャ構造を有するＣＢは廉価でかつ高い導電性と膨張収縮緩衝作用を有しているので、本発明の主旨によく合致している。   A second invention is a negative electrode for a non-aqueous electrolyte secondary battery in which the expansion / contraction buffer material is carbon black (CB) having a structure structure in the first invention. A CB having a structure structure is inexpensive and has high conductivity and expansion / shrinkage buffering action, and therefore well meets the gist of the present invention.

第３の発明は、第２の発明においてＣＢの添加量は、複合負極活物質１００重量部に対し、５重量部以上、３０重量部以下とした非水電解質二次電池用負極である。５重量部未満の場合、膨張収縮の応力を吸収できず、極板膨張が大きくなり、それに伴い充放電の繰り返しにより集電性が低下し、サイクル特性が低い。３０重量部より多いと含ケイ素粒子の割合が低くなり、黒鉛を負極活物質として用いた負極と比較して容量メリットがなくなる。   A third invention is a negative electrode for a non-aqueous electrolyte secondary battery in which the amount of CB added in the second invention is 5 to 30 parts by weight with respect to 100 parts by weight of the composite negative electrode active material. When the amount is less than 5 parts by weight, the stress of expansion and contraction cannot be absorbed, electrode plate expansion increases, and accordingly, current collection performance decreases due to repeated charge and discharge, resulting in poor cycle characteristics. When the amount is more than 30 parts by weight, the proportion of silicon-containing particles becomes low, and the capacity merit is lost as compared with a negative electrode using graphite as a negative electrode active material.

第４の発明は、第１の発明において含ケイ素粒子をＳｉＯｘ（０．０５＜ｘ＜１．９５）で表される酸化ケイ素粒子とした非水電解質二次電池用負極である。このような材料は放電容量密度が大きく、かつ充電時の膨張率がＳｉ単体より小さい。 A fourth invention is a negative electrode for a non-aqueous electrolyte secondary battery in which the silicon-containing particles in the first invention are silicon oxide particles represented by SiO x (0.05 <x <1.95). Such a material has a large discharge capacity density and an expansion coefficient during charging smaller than that of Si alone.

第５の発明は、上記いずれかの非水電解質二次電池用負極を用いて構成した非水電解質二次電池である。   5th invention is the nonaqueous electrolyte secondary battery comprised using either of the said negative electrodes for nonaqueous electrolyte secondary batteries.

以下、本発明の実施の形態について、図面を参照しながら説明する。なお、本発明は本明細書に記載された基本的な特徴に基づく限り、以下の内容に限定されない。   Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the following contents as long as it is based on the basic features described in this specification.

（実施の形態１）
図１（ａ）は本発明の実施の形態１における非水電解質二次電池の構成を示す断面図、図１（ｂ）は図１（ａ）の部分拡大図である。図２は本発明を用いた負極合剤層内部の構成、特に複合負極活物質粒子周囲の状態を示す模式図である。 (Embodiment 1)
FIG. 1A is a cross-sectional view showing the configuration of the nonaqueous electrolyte secondary battery according to Embodiment 1 of the present invention, and FIG. 1B is a partially enlarged view of FIG. FIG. 2 is a schematic diagram showing the internal structure of the negative electrode mixture layer using the present invention, particularly the state around the composite negative electrode active material particles.

この電池の発電要素は、長尺で薄い負極１と同じく長尺で薄い正極２とをセパレータ３を介して捲回して構成されている。ケース４はこのように構成された発電要素と、発電要素に含浸された非水電解質（図示せず）とを収容している。封口板５はケース４の開口部を封口している。ケース４には負極１のリード１Ｃが接続され、負極端子を兼ねている。封口板５のケース４と絶縁された金属部分に正極２のリード２Ｃが接続され、正極端子を構成している。   The power generation element of this battery is configured by winding a long and thin positive electrode 2 as well as a long and thin negative electrode 1 through a separator 3. The case 4 contains the power generation element configured as described above and a non-aqueous electrolyte (not shown) impregnated in the power generation element. The sealing plate 5 seals the opening of the case 4. The lead 4C of the negative electrode 1 is connected to the case 4 and also serves as a negative electrode terminal. A lead 2C of the positive electrode 2 is connected to a metal portion insulated from the case 4 of the sealing plate 5 to constitute a positive electrode terminal.

図１（ｂ）に示すように、負極１は集電体１Ａと、集電体１Ａの両面に設けられた合剤層１Ｂから構成されている。リード１Ｃの一端は集電体１Ａに接続されている。正極２は集電体２Ａと、集電体２Ａの両面に設けられた合剤層２Ｂから構成されている。リード２Ｃの一端は集電体２Ａに接続されている。   As shown in FIG. 1B, the negative electrode 1 is composed of a current collector 1A and a mixture layer 1B provided on both surfaces of the current collector 1A. One end of the lead 1C is connected to the current collector 1A. The positive electrode 2 includes a current collector 2A and a mixture layer 2B provided on both surfaces of the current collector 2A. One end of the lead 2C is connected to the current collector 2A.

合剤層１Ｂは図２に示すように、複合負極活物質１３と膨張収縮緩衝材１４とを含む。複合負極活物質１３は、少なくともリチウムイオンの吸蔵放出が可能な含ケイ素粒子１１と、その表面に付着したカーボンナノファイバ（ＣＮＦ）１２とから構成されている。含ケイ素粒子１１の粒子形状あるいは種類、膨張収縮の大きさには特に限定はない。   As shown in FIG. 2, the mixture layer 1 </ b> B includes a composite negative electrode active material 13 and an expansion / contraction buffer material 14. The composite negative electrode active material 13 includes at least silicon-containing particles 11 capable of occluding and releasing lithium ions, and carbon nanofibers (CNF) 12 attached to the surface thereof. There are no particular limitations on the particle shape or type of the silicon-containing particles 11 and the magnitude of expansion and contraction.

含ケイ素粒子１１には、Ｓｉ、ＳｉＯｘ（０．０５＜ｘ＜１．９５）、もしくはこれらいずれかの材料にＢ、Ｍｇ、Ｎｉ、Ｔｉ、Ｍｏ、Ｃｏ、Ｃａ、Ｃｒ、Ｃｕ、Ｆｅ、Ｍｎ、Ｎｂ、Ｔａ、Ｖ、Ｗ、Ｚｎ、Ｃ、Ｎ、Ｓｎから選択される少なくとも１種以上の元素でＳｉの一部を置換した、Ｓｉを少なくとも含む合金や化合物、あるいは固溶体などが適用できる。これらは単独で含ケイ素粒子１１を構成してもよく、複数種が同時に含ケイ素粒子１１を構成してもよい。複数種が同時に含ケイ素粒子１１を構成する例として、Ｓｉと酸素と窒素とを含む化合物や、Ｓｉと酸素とを含み、Ｓｉと酸素との比率が異なる複数の化合物の複合物などが挙げられる。このように含ケイ素粒子１１はＳｉの単体と、Ｓｉを含む合金と、Ｓｉを含む化合物からなる群のうち少なくとも１種を含む。この中でも、ＳｉＯｘ（０．０５＜ｘ＜１．９５）が、放電容量密度が大きく、かつ充電時の膨張率がＳｉ単体より小さいため好ましい。 The silicon-containing particles 11 include Si, SiO x (0.05 <x <1.95), or any of these materials including B, Mg, Ni, Ti, Mo, Co, Ca, Cr, Cu, Fe, An alloy or compound containing at least Si or a solid solution in which a part of Si is substituted with at least one element selected from Mn, Nb, Ta, V, W, Zn, C, N, and Sn can be applied. . These may constitute the silicon-containing particles 11 alone, or a plurality of types may constitute the silicon-containing particles 11 at the same time. Examples in which a plurality of types simultaneously constitute the silicon-containing particles 11 include a compound containing Si, oxygen and nitrogen, and a composite of a plurality of compounds containing Si and oxygen and having different ratios of Si and oxygen. . As described above, the silicon-containing particles 11 include at least one selected from the group consisting of a simple substance of Si, an alloy containing Si, and a compound containing Si. Among these, SiO x (0.05 <x <1.95) is preferable because the discharge capacity density is large and the expansion rate during charging is smaller than that of Si alone.

ＣＮＦ１２は、その成長の開始時点となる含ケイ素粒子１１の表面において含ケイ素粒子１１と付着している。すなわち、ＣＮＦ１２は、樹脂からなる結着剤を介さずに、含ケイ素粒子１１の表面に直接付着している。また、ＣＮＦ１２は成長形態により、少なくともその成長の開始時点となる一端において、含ケイ素粒子１１の表面と化学結合している場合もある。そのため電池内では集電に対する抵抗が小さくなり、高い電子伝導性が確保される。したがって、良好な充放電特性が期待できる。また、触媒元素（図示せず）によりＣＮＦ１２が含ケイ素粒子１１に結合している場合、ＣＮＦ１２が含ケイ素粒子１１から外れにくい。そのため、圧延負荷に対する負極１の耐性が向上する。   The CNF 12 adheres to the silicon-containing particles 11 on the surface of the silicon-containing particles 11 at the start of growth. That is, the CNF 12 is directly attached to the surface of the silicon-containing particles 11 without using a binder made of resin. Further, depending on the growth mode, CNF 12 may be chemically bonded to the surface of silicon-containing particles 11 at least at one end where the growth starts. Therefore, resistance to current collection is reduced in the battery, and high electron conductivity is ensured. Therefore, good charge / discharge characteristics can be expected. Further, when CNF 12 is bonded to the silicon-containing particles 11 by a catalytic element (not shown), the CNF 12 is not easily detached from the silicon-containing particles 11. Therefore, the tolerance of the negative electrode 1 with respect to the rolling load is improved.

ＣＮＦ１２の成長が終了するまでの間、触媒元素が良好な触媒作用を発揮するためには、触媒元素が含ケイ素粒子１１の表層部において金属状態で存在することが望ましい。触媒元素は、例えば粒径１ｎｍ〜１０００ｎｍの金属粒子の状態で存在することが望まれる。一方、ＣＮＦ１２の成長終了後においては、触媒元素からなる金属粒子を酸化することが望ましい。   Until the growth of CNF 12 is completed, it is desirable that the catalytic element is present in a metallic state in the surface layer portion of the silicon-containing particles 11 in order for the catalytic element to exhibit good catalytic action. The catalyst element is desirably present in a state of metal particles having a particle diameter of 1 nm to 1000 nm, for example. On the other hand, after the growth of CNF 12 is finished, it is desirable to oxidize the metal particles made of the catalyst element.

ＣＮＦ１２の繊維長は、１ｎｍ〜１ｍｍが好ましく、５００ｎｍ〜１００μｍがさらに好ましい。ＣＮＦ１２の繊維長が１ｎｍ未満では、電極の導電性を高める効果が小さくなりすぎ、また繊維長が１ｍｍを超えると、電極の活物質密度や容量が小さくなる傾向がある。ＣＮＦ１２の形態は、特に限定されないが、チューブ状カーボン、アコーディオン状カーボン、プレート状カーボンおよびヘーリング・ボーン状カーボンよりなる群から選択された少なくとも１種からなることが望ましい。ＣＮＦ１２は、成長する過程で触媒元素を自身の内部に取り込んでもよい。また、ＣＮＦ１２の繊維径は１ｎｍ〜１０００ｎｍが好ましく、５０ｎｍ〜３００ｎｍがさらに好ましい。   The fiber length of CNF12 is preferably 1 nm to 1 mm, and more preferably 500 nm to 100 μm. When the fiber length of CNF12 is less than 1 nm, the effect of increasing the conductivity of the electrode becomes too small, and when the fiber length exceeds 1 mm, the active material density and capacity of the electrode tend to decrease. Although the form of CNF 12 is not particularly limited, it is desirable that the CNF 12 is composed of at least one selected from the group consisting of tubular carbon, accordion carbon, plate carbon, and herringbone carbon. The CNF 12 may take a catalytic element into itself during the growth process. The fiber diameter of CNF12 is preferably 1 nm to 1000 nm, and more preferably 50 nm to 300 nm.

触媒元素は、金属状態でＣＮＦ１２を成長させるための活性点を与える。すなわち触媒元素が金属状態で表面に露出した含ケイ素粒子１１を、ＣＮＦ１２の原料ガスを含む高温雰囲気中に導入すると、ＣＮＦ１２の成長が進行する。活物質粒子の表面に触媒元素が存在しない場合には、ＣＮＦ１２は成長しない。   The catalytic element provides an active point for growing CNF 12 in the metallic state. That is, when the silicon-containing particles 11 whose catalytic elements are exposed in a metallic state are introduced into a high-temperature atmosphere containing the source gas of CNF 12, the growth of CNF 12 proceeds. If no catalytic element is present on the surface of the active material particles, the CNF 12 does not grow.

含ケイ素粒子１１の表面に触媒元素からなる金属粒子を設ける方法は、特に限定されないが、例えばリチウムイオンの吸蔵放出が可能な粒子の表面に金属粒子を担持させる方法などが好適である。   The method of providing the metal particles comprising the catalytic element on the surface of the silicon-containing particles 11 is not particularly limited, but for example, a method of supporting the metal particles on the surface of the particles capable of occluding and releasing lithium ions is suitable.

上記の方法で金属粒子を担持させる場合、固体の金属粒子を含ケイ素粒子１１と混合することも考えられるが、金属粒子の原料である金属化合物の溶液に、含ケイ素粒子１１を浸漬する方法が好適である。溶液に浸漬後の含ケイ素粒子１１から溶媒を除去し、必要に応じて加熱処理すると、表面に均一にかつ高分散状態で、粒径１ｎｍ〜１０００ｎｍ、好ましくは１０ｎｍ〜１００ｎｍの触媒元素からなる金属粒子を担持した含ケイ素粒子１１を得ることが可能である。   When the metal particles are supported by the above method, it is conceivable to mix the solid metal particles with the silicon-containing particles 11, but a method of immersing the silicon-containing particles 11 in a solution of a metal compound that is a raw material of the metal particles is available. Is preferred. When the solvent is removed from the silicon-containing particles 11 immersed in the solution and heat-treated as necessary, the metal is uniformly and highly dispersed on the surface, and is made of a catalyst element having a particle size of 1 nm to 1000 nm, preferably 10 nm to 100 nm. It is possible to obtain silicon-containing particles 11 carrying the particles.

触媒元素からなる金属粒子の粒径が１ｎｍ未満の場合、金属粒子の生成が非常に難しく、また１０００ｎｍを超えると、金属粒子の大きさが極端に不均一となり、ＣＮＦ１２を成長させることが困難になったり、導電性に優れた電極が得られなくなったりすることがある。そのため、触媒元素からなる金属粒子の粒径は１ｎｍ以上１０００ｎｍ以下であることが望ましい。   When the particle size of the metal particles composed of the catalyst element is less than 1 nm, it is very difficult to generate the metal particles. When the particle size exceeds 1000 nm, the size of the metal particles becomes extremely non-uniform, making it difficult to grow CNF12. Or an electrode having excellent conductivity may not be obtained. Therefore, it is desirable that the particle size of the metal particles made of the catalyst element is 1 nm or more and 1000 nm or less.

上記溶液を得るための金属化合物としては、硝酸ニッケル、硝酸コバルト、硝酸鉄、硝酸銅、硝酸マンガン、七モリブデン酸六アンモニウム四水和物などを挙げることができる。また溶液に用いる溶媒には、化合物の溶解度、電気化学的活性相との相性を考慮して、水、有機溶媒および水と有機溶媒との混合物の中から好適なものを選択すればよい。有機溶媒としては、例えばエタノール、イソプロピルアルコール、トルエン、ベンゼン、ヘキサン、テトラヒドロフランなどを用いることができる。   Examples of the metal compound for obtaining the solution include nickel nitrate, cobalt nitrate, iron nitrate, copper nitrate, manganese nitrate, hexaammonium hexamolybdate tetrahydrate and the like. A suitable solvent may be selected from water, an organic solvent, and a mixture of water and an organic solvent in consideration of the solubility of the compound and compatibility with the electrochemically active phase. As the organic solvent, for example, ethanol, isopropyl alcohol, toluene, benzene, hexane, tetrahydrofuran and the like can be used.

一方、触媒元素を含む合金粒子を合成し、これを含ケイ素粒子１１として用いることもできる。この場合、Ｓｉと触媒元素との合金を、通常の合金製造法により合成する。Ｓｉ元素は、電気化学的にリチウムと反応して合金を生成するので、電気化学的活性相が形成される。一方、触媒元素からなる金属相の少なくとも一部は、例えば粒径１０ｎｍ〜１００ｎｍの粒子状で合金粒子の表面に露出する。   On the other hand, alloy particles containing a catalyst element can be synthesized and used as the silicon-containing particles 11. In this case, an alloy of Si and a catalytic element is synthesized by a normal alloy manufacturing method. Since the Si element electrochemically reacts with lithium to form an alloy, an electrochemically active phase is formed. On the other hand, at least a part of the metal phase composed of the catalytic element is exposed on the surface of the alloy particles in the form of particles having a particle diameter of 10 nm to 100 nm, for example.

触媒元素からなる金属粒子もしくは金属相は、含ケイ素粒子１１の０．０１重量％〜１０重量％であることが望ましく、１重量％〜３重量％であることがさらに望ましい。金属粒子もしくは金属相の含有量が少なすぎると、ＣＮＦ１２を成長させるのに長時間を要し、生産効率が低下する場合がある。一方、触媒元素からなる金属粒子もしくは金属相の含有量が多すぎると、触媒元素の凝集により、不均一で太い繊維径のＣＮＦ１２が成長するため、合剤層１Ｂ中の導電性や活物質密度の低下に繋がる。また、電気化学的活性相の割合が相対的に少なくなり、複合負極活物質１３を高容量の電極材料とすることが困難となる。   The metal particles or metal phase composed of the catalytic element is preferably 0.01% by weight to 10% by weight of the silicon-containing particles 11, and more preferably 1% by weight to 3% by weight. If the content of the metal particles or the metal phase is too small, it takes a long time to grow the CNF 12, which may reduce the production efficiency. On the other hand, if the content of the metal particles or metal phase composed of the catalyst element is too large, the CNF 12 having a non-uniform and thick fiber diameter grows due to the aggregation of the catalyst element, so the conductivity and active material density in the mixture layer 1B Leading to a decline. In addition, the proportion of the electrochemically active phase is relatively reduced, making it difficult to make the composite negative electrode active material 13 into a high-capacity electrode material.

次に、含ケイ素粒子１１とＣＮＦ１２とから構成された複合負極活物質１３の製造方法について述べる。この製造方法は以下の４つのステップで構成される。   Next, the manufacturing method of the composite negative electrode active material 13 comprised from the silicon-containing particle | grains 11 and CNF12 is described. This manufacturing method includes the following four steps.

（ａ）リチウムの吸蔵放出が可能な含ケイ素粒子１１の少なくとも表層部に、ＣＮＦ１２の成長を促進するＣｕ、Ｆｅ、Ｃｏ、Ｎｉ、ＭｏおよびＭｎよりなる群から選択された少なくとも１種の触媒元素を設けるステップ。   (A) At least one catalyst element selected from the group consisting of Cu, Fe, Co, Ni, Mo, and Mn that promotes the growth of CNF 12 in at least the surface layer portion of the silicon-containing particles 11 capable of occluding and releasing lithium. Providing a step.

（ｂ）炭素含有ガスおよび水素ガスを含む雰囲気中で、含ケイ素粒子１１の表面に、ＣＮＦ１２を成長させるステップ。   (B) A step of growing CNF 12 on the surface of the silicon-containing particles 11 in an atmosphere containing a carbon-containing gas and a hydrogen gas.

（ｃ）不活性ガス雰囲気中で、ＣＮＦ１２が付着した含ケイ素粒子１１を４００℃以上１６００℃以下で焼成するステップ。   (C) A step of firing the silicon-containing particles 11 to which the CNF 12 is adhered in an inert gas atmosphere at 400 ° C. or higher and 1600 ° C. or lower.

（ｄ）ＣＮＦ１２が付着した含ケイ素粒子１１を解砕してタップ密度を０．４２ｇ／ｃｍ３以上０．９１ｇ／ｃｍ３以下に調整するステップ。 (D) CNF12 the step of adjusting the tap density was crushed silicon-containing particles 11 adhering to the following 0.42 g / cm 3 or more 0.91 g / cm 3.

ステップ（ｃ）の後、さらに、大気中で複合負極活物質１３を１００℃以上４００℃以下で熱処理して触媒元素を酸化してもよい。１００℃以上４００℃以下の熱処理であれば、ＣＮＦ１２を酸化させずに触媒元素だけを酸化することが可能である。   After step (c), the composite negative electrode active material 13 may be further heat-treated at 100 ° C. or higher and 400 ° C. or lower in the atmosphere to oxidize the catalytic element. If the heat treatment is performed at 100 ° C. or more and 400 ° C. or less, it is possible to oxidize only the catalytic element without oxidizing CNF 12.

ステップ（ａ）としては、含ケイ素粒子１１の表面に触媒元素からなる金属粒子を担持するステップ、触媒元素を含む含ケイ素粒子１１の表面を還元するステップ、Ｓｉ元素と触媒元素との合金粒子を合成するステップなどが挙げられる。ただしステップ（ａ）は上記に限られるものではない。   As the step (a), a step of supporting metal particles comprising a catalytic element on the surface of the silicon-containing particles 11, a step of reducing the surface of the silicon-containing particles 11 containing the catalytic element, and an alloy particle of Si element and catalytic element Examples include a step of synthesis. However, step (a) is not limited to the above.

次に、ステップ（ｂ）において、含ケイ素粒子１１の表面にＣＮＦ１２を成長させる際の条件について説明する。少なくとも表層部に触媒元素を有する含ケイ素粒子１１を、ＣＮＦ１２の原料ガスを含む高温雰囲気中に導入するとＣＮＦ１２の成長が進行する。例えばセラミック製反応容器に含ケイ素粒子１１を投入し、不活性ガスもしくは還元力を有するガス中で１００℃〜１０００℃、好ましくは３００℃〜６００℃の高温になるまで昇温させる。その後、ＣＮＦ１２の原料ガスである炭素含有ガスと水素ガスとを反応容器に導入する。反応容器内の温度が１００℃未満では、ＣＮＦ１２の成長が起こらないか、成長が遅すぎて生産性が損なわれる。また、反応容器内の温度が１０００℃を超えると、原料ガスの分解が促進されＣＮＦ１２が成長し難くなる。   Next, conditions for growing CNF 12 on the surface of the silicon-containing particles 11 in step (b) will be described. When silicon-containing particles 11 having a catalytic element at least in the surface layer portion are introduced into a high-temperature atmosphere containing a source gas of CNF 12, the growth of CNF 12 proceeds. For example, the silicon-containing particles 11 are put into a ceramic reaction vessel and heated up to a high temperature of 100 ° C. to 1000 ° C., preferably 300 ° C. to 600 ° C. in an inert gas or a gas having a reducing power. Thereafter, carbon-containing gas and hydrogen gas, which are source gases of CNF 12, are introduced into the reaction vessel. If the temperature in the reaction vessel is less than 100 ° C., the growth of CNF 12 does not occur or the growth is too slow and the productivity is impaired. On the other hand, when the temperature in the reaction vessel exceeds 1000 ° C., decomposition of the raw material gas is promoted and CNF 12 is difficult to grow.

原料ガスとしては、炭素含有ガスと水素ガスとの混合ガスが好適である。炭素含有ガスとしては、メタン、エタン、エチレン、ブタン、一酸化炭素などを用いることができる。混合ガスにおける炭素含有ガスのモル比（体積比）は、２０％〜８０％が好適である。含ケイ素粒子１１の表面に金属状態の触媒元素が露出していない場合には、水素ガスの割合を多めに制御することで、触媒元素の還元とＣＮＦ１２の成長とを並行して進行させることができる。ＣＮＦ１２の成長を終了させる際には、炭素含有ガスと水素ガスとの混合ガスを不活性ガスに置換し、反応容器内を室温まで冷却する。   As the source gas, a mixed gas of carbon-containing gas and hydrogen gas is suitable. As the carbon-containing gas, methane, ethane, ethylene, butane, carbon monoxide, or the like can be used. The molar ratio (volume ratio) of the carbon-containing gas in the mixed gas is preferably 20% to 80%. When the catalytic element in the metallic state is not exposed on the surface of the silicon-containing particles 11, the reduction of the catalytic element and the growth of the CNF 12 can proceed in parallel by controlling the ratio of hydrogen gas to a large extent. it can. When terminating the growth of CNF 12, the mixed gas of carbon-containing gas and hydrogen gas is replaced with an inert gas, and the inside of the reaction vessel is cooled to room temperature.

続いて、ステップ（ｃ）にて、ＣＮＦ１２が付着した含ケイ素粒子１１を、不活性ガス雰囲気中にて４００℃以上、１６００℃以下で焼成する。このようにすることで電池の初期充電時に進行する電解質とＣＮＦ１２との不可逆反応が抑制され、優れた充放電効率を得ることができるため好ましい。このような焼成行程を行わないか、もしくは焼成温度が４００℃未満では、上記の不可逆反応が抑制されず電池の充放電効率が低下することがある。また、焼成温度が１６００℃を超えると、含ケイ素粒子１１の電気化学的活性相とＣＮＦ１２とが反応して活性相が不活性化したり、電気化学的活性相が還元されて容量低下を引き起こしたりすることがある。例えば、含ケイ素粒子１１の電気化学的活性相がＳｉである場合には、ＳｉとＣＮＦ１２とが反応して不活性な炭化ケイ素が生成してしまい、電池の充放電容量の低下を引き起こす。なお、含ケイ素粒子１１がＳｉの場合、焼成温度は１０００℃以上、１６００℃以下が特に好ましい。なお、成長条件によってＣＮＦ１２の結晶性を高めることもできる。このようにＣＮＦ１２の結晶性が高い場合には電解質とＣＮＦ１２との不可逆反応も抑制されるため、ステップ（ｃ）は必須ではない。   Subsequently, in step (c), the silicon-containing particles 11 to which CNF 12 is adhered are fired at 400 ° C. or higher and 1600 ° C. or lower in an inert gas atmosphere. By doing in this way, since the irreversible reaction of the electrolyte and CNF12 which advance at the time of the initial charge of a battery is suppressed, and the outstanding charging / discharging efficiency can be obtained, it is preferable. If such a firing process is not performed, or if the firing temperature is less than 400 ° C., the above irreversible reaction may not be suppressed, and the charge / discharge efficiency of the battery may decrease. Further, when the firing temperature exceeds 1600 ° C., the electrochemically active phase of the silicon-containing particles 11 reacts with the CNF 12 to inactivate the active phase, or the electrochemically active phase is reduced to cause a decrease in capacity. There are things to do. For example, when the electrochemically active phase of the silicon-containing particles 11 is Si, Si and CNF 12 react with each other to generate inactive silicon carbide, causing a reduction in charge / discharge capacity of the battery. When the silicon-containing particles 11 are Si, the firing temperature is particularly preferably 1000 ° C. or higher and 1600 ° C. or lower. Note that the crystallinity of the CNF 12 can be increased depending on the growth conditions. Thus, when the crystallinity of CNF12 is high, since the irreversible reaction of electrolyte and CNF12 is also suppressed, step (c) is not essential.

不活性ガス中で焼成後の複合負極活物質１３は、さらに触媒元素からなる金属粒子もしくは金属相の少なくとも一部（例えば表面）を酸化するために、大気中で、１００℃以上、４００℃以下で熱処理することが好ましい。熱処理温度が１００℃未満では、金属を酸化することは困難であり、４００℃を超えると成長させたＣＮＦ１２が燃焼してしまうことがある。   The composite negative electrode active material 13 after firing in an inert gas further oxidizes at least a part (for example, the surface) of metal particles or a metal phase composed of a catalytic element in the atmosphere at 100 ° C. or higher and 400 ° C. or lower. It is preferable to heat-treat with. If the heat treatment temperature is less than 100 ° C., it is difficult to oxidize the metal, and if it exceeds 400 ° C., the grown CNF 12 may burn.

ステップ（ｄ）ではＣＮＦ１２が付着した焼成後の含ケイ素粒子１１を解砕する。このようにすることにより、充填性の良好な複合負極活物質１３が得られるため好ましい。ただし、解砕しなくてもタップ密度が０．４２ｇ／ｃｍ３以上、０．９１ｇ／ｃｍ３以下の場合は必ずしも解砕する必要はない。すなわち、充填性のよい含ケイ素粒子を原料に用いた場合、解砕する必要がない場合もある。 In step (d), the fired silicon-containing particles 11 to which CNF 12 is adhered are crushed. By doing in this way, since the composite negative electrode active material 13 with favorable filling property is obtained, it is preferable. However, it disintegrated rather tap density also is 0.42 g / cm 3 or more, it is not always necessary to crushing in the case of 0.91 g / cm 3 or less. That is, when silicon-containing particles with good filling properties are used as a raw material, it may not be necessary to crush.

膨張収縮緩衝材１４は導電性を有し、含ケイ素粒子１１の膨張収縮によるストレスを吸収する機能があれば材料は特に限定されない。例えば、樹脂などの弾性を有する粒子の表面に銅などの導電性物質を固着した複合材料が適用可能である。特に、ストラクチャ構造を有するカーボンブラック（ＣＢ）を用いることが好ましい。ストラクチャ構造を有するＣＢは廉価でかつ高い導電性と膨張収縮緩衝作用を有しているので、本発明の主旨によく合致している。ＣＢとしてはファーネスブラックやランプブラック、ケッチェンブラックなどを挙げることができるが、高ストラクチャ構造を有し、かつ導電性が高いという観点からアセチレンブラック（ＡＢ）を用いるのがより好ましい。これらストラクチャ構造では、粒子がアグロメートした一次粒子の融合した状態や、アグロメレートと呼ばれる凝集会合体の状態であり、ファンデアワールズ力で超細繊維が絡んだ細繊維の集合体が構成されている。またＣＢのストラクチャ構造を得る方法としては、ＣＢが高い疎液性を有していることを利用し、適度な分散剤（可溶性結着剤や増粘剤、表面活性剤など）を添加した溶媒にＣＢと他の負極材料とを同時に混入し分散する方法が挙げられる。ここでＣＢのストラクチャ構造を破壊しないために、分散時には混入物がファニキュラー状態（粒子間の液体が連続して網目状に存在しその間に気泡が孤立して点在する状態）とならないようにするのが好ましい。   The expansion / shrinkage buffer material 14 has conductivity, and the material is not particularly limited as long as it has a function of absorbing stress due to expansion / contraction of the silicon-containing particles 11. For example, a composite material in which a conductive substance such as copper is fixed to the surface of an elastic particle such as a resin is applicable. In particular, it is preferable to use carbon black (CB) having a structure structure. A CB having a structure structure is inexpensive and has high conductivity and expansion / shrinkage buffering action, and therefore well meets the gist of the present invention. Examples of CB include furnace black, lamp black, and ketjen black, and acetylene black (AB) is more preferably used from the viewpoint of having a high structure structure and high conductivity. In these structure structures, the primary particles in which the particles are agglomerated are in a fused state or a state of agglomerated aggregate called agglomerate, and an aggregate of fine fibers in which ultrafine fibers are entangled by van der Waals force is formed. In addition, as a method for obtaining a CB structure structure, a solvent in which an appropriate dispersant (such as a soluble binder, a thickener, or a surface active agent) is added using the fact that CB has high lyophobic properties. And a method of simultaneously mixing and dispersing CB and other negative electrode materials. Here, in order not to destroy the structure structure of CB, the contaminants are not in a funicular state during dispersion (a state in which liquid between particles is continuously present in a network shape and bubbles are isolated and interspersed therebetween). It is preferable to do this.

次に、負極１の製造方法について説明する。前述のようにしてＣＮＦ１２を表面に付着させた含ケイ素粒子１１からなる複合負極活物質１３に膨張収縮緩衝材１４を混合した後、結着剤と溶媒とをさらに混合する。このときフェニキュラー状態にならないように混合してペースト状に合剤スラリーを調製する。結着剤、溶媒としては、例えばポリフッ化ビニリデン（ＰＶＤＦ）とＮ−メチル−２−ピロリドン（ＮＭＰ）、あるいはポリテトラフルオロエチレンのエマルジョンと水などが使用可能である。結着剤としてはこれ以外に、ポリエチレン、ポリプロピレン、アラミド樹脂、ポリアミド、ポリイミド、ポリアミドイミド、ポリアクリルニトリル、ポリアクリル酸、ポリアクリル酸メチルエステル、ポリアクリル酸エチルエステル、ポリアクリル酸ヘキシルエステル、ポリメタクリル酸、ポリメタクリル酸メチルエステル、ポリメタクリル酸エチルエステル、ポリメタクリル酸ヘキシルエステル、ポリ酢酸ビニル、ポリビニルピロリドン、ポリエーテル、ポリエーテルサルフォン、ヘキサフルオロポリプロピレン、スチレンブタジエンゴム、カルボキシメチルセルロースなどが使用可能である。また、テトラフルオロエチレン、ヘキサフルオロエチレン、ヘキサフルオロプロピレン、パーフルオロアルキルビニルエーテル、フッ化ビニリデン、クロロトリフルオロエチレン、エチレン、プロピレン、ペンタフルオロプロピレン、フルオロメチルビニルエーテル、アクリル酸、ヘキサジエンより選択された２種以上の材料の共重合体を用いてもよい。   Next, the manufacturing method of the negative electrode 1 is demonstrated. After the expansion / shrinkage buffer material 14 is mixed with the composite negative electrode active material 13 composed of the silicon-containing particles 11 having the CNF 12 attached to the surface as described above, the binder and the solvent are further mixed. At this time, a mixture slurry is prepared in a paste state by mixing so as not to become a phencular state. As the binder and the solvent, for example, polyvinylidene fluoride (PVDF) and N-methyl-2-pyrrolidone (NMP), or an emulsion of polytetrafluoroethylene and water can be used. Other binders include polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polyacrylic acid methyl ester, polyacrylic acid ethyl ester, polyacrylic acid hexyl ester, poly Methacrylic acid, polymethacrylic acid methyl ester, polymethacrylic acid ethyl ester, polymethacrylic acid hexyl ester, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, styrene butadiene rubber, carboxymethylcellulose, etc. can be used It is. Two types selected from tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid, and hexadiene A copolymer of the above materials may be used.

得られたスラリーを、集電体１Ａの両面にドクターブレードを用いて塗布し、乾燥させ、集電体１Ａ上に合剤層１Ｂを形成する。その後、ロール圧延して合剤層１Ｂの厚みを調整する。でき上がった帯状の負極連続体を所定の寸法に打ち抜くかまたは切断する。そして集電体１Ａの露出した部分にニッケルや銅のリード１Ｃを溶接などにより接続して負極１が完成する。   The obtained slurry is applied to both surfaces of the current collector 1A using a doctor blade and dried to form a mixture layer 1B on the current collector 1A. Then, it rolls and adjusts the thickness of the mixture layer 1B. The completed strip-shaped negative electrode continuum is punched or cut to a predetermined size. Then, a nickel or copper lead 1C is connected to the exposed portion of the current collector 1A by welding or the like to complete the negative electrode 1.

なお、集電体１Ａには、ステンレス鋼、ニッケル、銅、チタンなどの金属箔、炭素や導電性樹脂の薄膜などが利用可能である。さらに、カーボン、ニッケル、チタンなどで表面処理を施してもよい。   The current collector 1A can be made of a metal foil such as stainless steel, nickel, copper, or titanium, or a thin film of carbon or conductive resin. Further, surface treatment may be performed with carbon, nickel, titanium or the like.

また、必要に応じて鱗片状黒鉛などの天然黒鉛、人造黒鉛、膨張黒鉛などのグラファイト類、炭素繊維、金属繊維などの導電性繊維類、銅やニッケルなどの金属粉末類、ポリフェニレン誘導体などの有機導電性材料などの導電剤を合剤層１Ｂに混入させてもよい。その場合、これらの導電剤粒子にもＣＮＦ１２を付着させておくことが好ましい。   If necessary, natural graphite such as flake graphite, graphite such as artificial graphite and expanded graphite, conductive fibers such as carbon fiber and metal fiber, metal powders such as copper and nickel, and organic such as polyphenylene derivatives A conductive agent such as a conductive material may be mixed into the mixture layer 1B. In that case, it is preferable to attach CNF12 to these conductive agent particles.

次に正極２について説明する。合剤層２ＢはＬｉＣｏＯ２やＬｉＮｉＯ２、Ｌｉ２ＭｎＯ４、またはこれらの混合あるいは複合化合物などのような含リチウム複合酸化物を正極活物質として含む。正極活物質としては上記以外に、ＬｉＭＰＯ４（Ｍ＝Ｖ、Ｆｅ、Ｎｉ、Ｍｎ）の一般式で表されるオリビン型リン酸リチウム、Ｌｉ２ＭＰＯ４Ｆ（Ｍ＝Ｖ、Ｆｅ、Ｎｉ、Ｍｎ）の一般式で表されるフルオロリン酸リチウムなども利用可能である。さらにこれら含リチウム化合物の一部を異種元素で置換してもよい。金属酸化物、リチウム酸化物、導電剤などで表面処理してもよく、表面を疎水化処理してもよい。 Next, the positive electrode 2 will be described. The mixture layer 2B includes a lithium-containing composite oxide such as LiCoO 2 , LiNiO 2 , Li 2 MnO 4 , or a mixture or composite compound thereof as a positive electrode active material. In addition to the above, as the positive electrode active material, olivine type lithium phosphate represented by the general formula of LiMPO 4 (M = V, Fe, Ni, Mn), Li 2 MPO 4 F (M = V, Fe, Ni, Mn) ) Lithium fluorophosphate represented by the general formula can also be used. Further, a part of these lithium-containing compounds may be substituted with a different element. Surface treatment may be performed with a metal oxide, lithium oxide, a conductive agent, or the like, or the surface may be subjected to a hydrophobic treatment.

合剤層２Ｂはさらに導電剤と、結着剤とを含む。導電剤としては、天然黒鉛や人造黒鉛のグラファイト類、アセチレンブラック、ケッチェンブラック、チャンネルブラック、ファーネスブラック、ランプブラック、サーマルブラックなどのカーボンブラック類、炭素繊維や金属繊維などの導電性繊維類、フッ化カーボン、アルミニウムなどの金属粉末類、酸化亜鉛やチタン酸カリウムなどの導電性ウィスカー類、酸化チタンなどの導電性金属酸化物、フェニレン誘導体などの有機導電性材料を用いることができる。   The mixture layer 2B further includes a conductive agent and a binder. As the conductive agent, natural graphite and artificial graphite graphite, acetylene black, ketjen black, channel black, furnace black, lamp black, thermal black and other carbon black, conductive fibers such as carbon fiber and metal fiber, Metal powders such as carbon fluoride and aluminum, conductive whiskers such as zinc oxide and potassium titanate, conductive metal oxides such as titanium oxide, and organic conductive materials such as phenylene derivatives can be used.

また結着剤としては、負極１に用いたものと同様のものを用いることができる。すなわち、ＰＶＤＦ、ポリテトラフルオロエチレン、ポリエチレン、ポリプロピレン、アラミド樹脂、ポリアミド、ポリイミド、ポリアミドイミド、ポリアクリルニトリル、ポリアクリル酸、ポリアクリル酸メチルエステル、ポリアクリル酸エチルエステル、ポリアクリル酸ヘキシルエステル、ポリメタクリル酸、ポリメタクリル酸メチルエステル、ポリメタクリル酸エチルエステル、ポリメタクリル酸ヘキシルエステル、ポリ酢酸ビニル、ポリビニルピロリドン、ポリエーテル、ポリエーテルサルフォン、ヘキサフルオロポリプロピレン、スチレンブタジエンゴム、カルボキシメチルセルロースなどが使用可能である。また、テトラフルオロエチレン、ヘキサフルオロエチレン、ヘキサフルオロプロピレン、パーフルオロアルキルビニルエーテル、フッ化ビニリデン、クロロトリフルオロエチレン、エチレン、プロピレン、ペンタフルオロプロピレン、フルオロメチルビニルエーテル、アクリル酸、ヘキサジエンより選択された２種以上の材料の共重合体を用いてもよい。またこれらのうちから選択された２種以上を混合して用いてもよい。   Moreover, as a binder, the thing similar to what was used for the negative electrode 1 can be used. That is, PVDF, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polyacrylic acid methyl ester, polyacrylic acid ethyl ester, polyacrylic acid hexyl ester, poly Methacrylic acid, polymethacrylic acid methyl ester, polymethacrylic acid ethyl ester, polymethacrylic acid hexyl ester, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, styrene butadiene rubber, carboxymethylcellulose, etc. can be used It is. Two types selected from tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid, and hexadiene A copolymer of the above materials may be used. Two or more selected from these may be mixed and used.

正極２に用いる集電体２Ａやリード２Ｃとしては、ステンレス鋼、アルミニウム（Ａｌ）、チタン、炭素、導電性樹脂などが使用可能である。またこのいずれかの材料に、カーボン、ニッケル、チタンなどで表面処理してもよい。   As the current collector 2A and the lead 2C used for the positive electrode 2, stainless steel, aluminum (Al), titanium, carbon, conductive resin, or the like can be used. Further, any of these materials may be surface-treated with carbon, nickel, titanium or the like.

非水電解質には有機溶媒に溶質を溶解した電解質溶液や、これらを含み高分子で非流動化されたいわゆるポリマー電解質層が適用可能である。少なくとも電解質溶液を用いる場合には正極２と負極１との間にポリエチレン、ポリプロピレン、アラミド樹脂、アミドイミド、ポリフェニレンサルファイド、ポリイミドなどからなる不織布や微多孔膜などのセパレータ３を用い、これに溶液を含浸させるのが好ましい。またセパレータ３の内部あるいは表面には、アルミナ、マグネシア、シリカ、チタニアなどの耐熱性フィラーを含んでもよい。セパレータ３とは別に、これらのフィラーと、電極に用いるのと同様の結着剤とから構成される耐熱層を設けてもよい。   As the non-aqueous electrolyte, an electrolyte solution in which a solute is dissolved in an organic solvent, or a so-called polymer electrolyte layer containing these and non-fluidized with a polymer can be applied. When using an electrolyte solution at least, a separator 3 such as a nonwoven fabric or a microporous membrane made of polyethylene, polypropylene, aramid resin, amideimide, polyphenylene sulfide, polyimide, etc. is used between the positive electrode 2 and the negative electrode 1 and impregnated with the solution. Preferably. Further, the inside or the surface of the separator 3 may contain a heat-resistant filler such as alumina, magnesia, silica, and titania. Apart from the separator 3, a heat-resistant layer composed of these fillers and a binder similar to that used for the electrode may be provided.

非水電解質の材料は、活物質の酸化還元電位などを基に選択される。非水電解質に用いるのが好ましい溶質としては、ＬｉＰＦ６、ＬｉＢＦ４、ＬｉＣｌＯ４、ＬｉＡｌＣｌ４、ＬｉＳｂＦ６、ＬｉＳＣＮ、ＬｉＣＦ３ＳＯ３、ＬｉＣＦ３ＣＯ２、Ｌｉ（ＣＦ３ＳＯ２）２、ＬｉＡｓＦ６、ＬｉＢ１０Ｃｌ１０、低級脂肪族カルボン酸リチウム、ＬｉＦ、ＬｉＣｌ、ＬｉＢｒ、ＬｉＩ、クロロボランリチウム、ビス（１，２−ベンゼンジオレート（２−）−Ｏ，Ｏ’）ほう酸リチウム、ビス（２，３−ナフタレンジオレート（２−）−Ｏ，Ｏ’）ほう酸リチウム、ビス（２，２’−ビフェニルジオレート（２−）−Ｏ，Ｏ’）ほう酸リチウム、ビス（２，２’−ビフェニルジオレート（２−）−Ｏ，Ｏ’）ほう酸リチウム、ビス（５−フルオロ−２−オレート−１−ベンゼンスルホン酸−Ｏ，Ｏ’）ほう酸リチウムなどのほう酸塩類、（ＣＦ３ＳＯ２）２ＮＬｉ、ＬｉＮ（ＣＦ３ＳＯ２）（Ｃ４Ｆ９ＳＯ２）、（Ｃ２Ｆ５ＳＯ２）２ＮＬｉ、テトラフェニルホウ酸リチウムなど、一般にリチウム電池で使用されている塩類が適用できる。 The nonaqueous electrolyte material is selected based on the redox potential of the active material. Solutes preferably used for the nonaqueous electrolyte include LiPF 6 , LiBF 4 , LiClO 4 , LiAlCl 4 , LiSbF 6 , LiSCN, LiCF 3 SO 3 , LiCF 3 CO 2 , Li (CF 3 SO 2 ) 2 , LiAsF 6. , LiB 10 Cl 10 , lower aliphatic lithium carboxylate, LiF, LiCl, LiBr, LiI, lithium chloroborane, bis (1,2-benzenediolate (2-)-O, O ′) lithium borate, bis (2 , 3-Naphthalenedioleate (2-)-O, O ') lithium borate, bis (2,2'-biphenyldiolate (2-)-O, O') lithium borate, bis (2,2'-biphenyl) Dioleate (2-)-O, O ′) lithium borate, bis (5-fluoro-2-olate-1-benzenesulfonic acid-O, O ′) Borates such as lithium borate, (CF 3 SO 2 ) 2 NLi, LiN (CF 3 SO 2 ) (C 4 F 9 SO 2 ), (C 2 F 5 SO 2 ) 2 NLi, lithium tetraphenylborate, etc. Generally, salts used in lithium batteries can be applied.

さらに上記塩を溶解させる有機溶媒には、エチレンカーボネート、プロピレンカーボネート、ブチレンカーボネート、ビニレンカーボネート、ジメチルカーボネート、ジエチルカーボネート、エチルメチルカーボネート、ジプロピルカーボネート、ギ酸メチル、酢酸メチル、プロピオン酸メチル、プロピオン酸エチル、ジメトキシメタン、γ−ブチロラクトン、γ−バレロラクトン、１，２−ジエトキシエタン、１，２−ジメトキシエタン、エトキシメトキシエタン、トリメトキシメタン、テトラヒドロフラン、２−メチルテトラヒドロフランなどのテトラヒドロフラン誘導体、ジメチルスルホキシド、１，３−ジオキソラン、４−メチル−１，３−ジオキソランなどのジオキソラン誘導体、ホルムアミド、アセトアミド、ジメチルホルムアミド、アセトニトリル、プロピルニトリル、ニトロメタン、エチルモノグライム、リン酸トリエステル、酢酸エステル、プロピオン酸エステル、スルホラン、３−メチルスルホラン、１，３−ジメチル−２−イミダゾリジノン、３−メチル−２−オキサゾリジノン、プロピレンカーボネート誘導体、エチルエーテル、ジエチルエーテル、１，３−プロパンサルトン、アニソール、フルオロベンゼンなどの１種またはそれ以上の混合物など、一般にリチウム電池で使用されているような溶媒が適用できる。   Further, the organic solvent for dissolving the salt includes ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dipropyl carbonate, methyl formate, methyl acetate, methyl propionate, ethyl propionate. , Tetrahydrofuran derivatives such as dimethoxymethane, γ-butyrolactone, γ-valerolactone, 1,2-diethoxyethane, 1,2-dimethoxyethane, ethoxymethoxyethane, trimethoxymethane, tetrahydrofuran, 2-methyltetrahydrofuran, dimethyl sulfoxide, Dioxolane derivatives such as 1,3-dioxolane and 4-methyl-1,3-dioxolane, formamide, acetamide, dimethylformamide , Acetonitrile, propylnitrile, nitromethane, ethyl monoglyme, phosphoric acid triester, acetic acid ester, propionic acid ester, sulfolane, 3-methylsulfolane, 1,3-dimethyl-2-imidazolidinone, 3-methyl-2- Solvents such as those commonly used in lithium batteries, such as oxazolidinone, propylene carbonate derivatives, ethyl ether, diethyl ether, 1,3-propane sultone, anisole, one or more mixtures of fluorobenzene, etc., can be applied.

さらに、ビニレンカーボネート、シクロヘキシルベンゼン、ビフェニル、ジフェニルエーテル、ビニルエチレンカーボネート、ジビニルエチレンカーボネート、フェニルエチレンカーボネート、ジアリルカーボネート、フルオロエチレンカーボネート、カテコールカーボネート、酢酸ビニル、エチレンサルファイト、プロパンサルトン、トリフルオロプロピレンカーボネート、ジベニゾフラン、２，４−ジフルオロアニソール、ｏ−ターフェニル、ｍ−ターフェニルなどの添加剤を含んでいてもよい。   Furthermore, vinylene carbonate, cyclohexyl benzene, biphenyl, diphenyl ether, vinyl ethylene carbonate, divinyl ethylene carbonate, phenyl ethylene carbonate, diallyl carbonate, fluoroethylene carbonate, catechol carbonate, vinyl acetate, ethylene sulfite, propane sultone, trifluoropropylene carbonate, Additives such as dibenisofuran, 2,4-difluoroanisole, o-terphenyl, m-terphenyl may be included.

なお、非水電解質は、ポリエチレンオキサイド、ポリプロピレンオキサイド、ポリホスファゼン、ポリアジリジン、ポリエチレンスルフィド、ポリビニルアルコール、ポリフッ化ビニリデン、ポリヘキサフルオロプロピレンなどの高分子材料の１種またはそれ以上の混合物などに上記溶質を混合して、固体電解質として用いてもよい。また、上記有機溶媒と混合してゲル状で用いてもよい。さらに、リチウム窒化物、リチウムハロゲン化物、リチウム酸素酸塩、Ｌｉ４ＳｉＯ４、Ｌｉ４ＳｉＯ４−ＬｉＩ−ＬｉＯＨ、Ｌｉ３ＰＯ４−Ｌｉ４ＳｉＯ４、Ｌｉ２ＳｉＳ３、Ｌｉ３ＰＯ４−Ｌｉ２Ｓ−ＳｉＳ２、硫化リン化合物などの無機材料を固体電解質として用いてもよい。 The non-aqueous electrolyte is composed of one or more kinds of polymer materials such as polyethylene oxide, polypropylene oxide, polyphosphazene, polyaziridine, polyethylene sulfide, polyvinyl alcohol, polyvinylidene fluoride, polyhexafluoropropylene, and the like. May be used as a solid electrolyte. Moreover, you may mix with the said organic solvent and use it in a gel form. Further, lithium nitride, lithium halide, lithium oxyacid salt, Li 4 SiO 4, Li 4 SiO 4 -LiI-LiOH, Li 3 PO 4 -Li 4 SiO 4, Li 2 SiS 3, Li 3 PO 4 -Li Inorganic materials such as 2 S—SiS 2 and phosphorus sulfide compounds may be used as the solid electrolyte.

ケース４は、鉄、ニッケルめっきを施した鉄、アルミニウムなどの金属で構成されている。封口板５はケース４と絶縁するための絶縁部材５Ａと正極端子として機能する金属部分５Ｂとを有する。図１（ａ）のようにケース４をかしめて封口板５を固定する場合には絶縁部材５Ａはケース４の一部で圧縮されるガスケットである。ガスケットは硬質ポリプロピレンなどの樹脂材料からなる。ハーメチックシールにより封口する場合には、絶縁部材５Ａはガラスなどの無機材料からなる。なお、封口板５の内部には電池内圧が上昇した際に作動する防爆機構を組み込んでもよい。   The case 4 is made of a metal such as iron, nickel-plated iron, or aluminum. The sealing plate 5 includes an insulating member 5A for insulating from the case 4 and a metal portion 5B that functions as a positive terminal. When the case 4 is caulked and the sealing plate 5 is fixed as shown in FIG. 1A, the insulating member 5 </ b> A is a gasket that is compressed by a part of the case 4. The gasket is made of a resin material such as hard polypropylene. In the case of sealing with a hermetic seal, the insulating member 5A is made of an inorganic material such as glass. An explosion-proof mechanism that operates when the battery internal pressure rises may be incorporated in the sealing plate 5.

次に図２を用いて充放電に伴う合剤層１Ｂ中の構造変化について説明する。図２（ａ）は充電時の複合負極活物質１３周囲の状態を示す模式図、図２（ｂ）は同放電時の状態を示す模式図である。   Next, the structural change in the mixture layer 1B accompanying charging / discharging is demonstrated using FIG. FIG. 2A is a schematic diagram showing a state around the composite negative electrode active material 13 during charging, and FIG. 2B is a schematic diagram showing a state during the discharging.

合剤層１Ｂ中には含ケイ素粒子１１とＣＮＦ１２とからなる複合負極活物質１３と、導電性を有する膨張収縮緩衝材１４とが含まれている。ＣＮＦ１２の一端は含ケイ素粒子１１の表面に付着されている。膨張収縮緩衝材１４は複合負極活物質１３の粒子間に介在している。すなわち導電性のＣＮＦ１２の一端は含ケイ素粒子１１の表面に固着され、他端は膨張収縮緩衝材１４に接続されている。その結果、導電性に乏しい含ケイ素粒子１１間には膨張収縮緩衝材１４を介して導電ネットワークが形成されている。   In the mixture layer 1B, a composite negative electrode active material 13 composed of silicon-containing particles 11 and CNF 12 and a conductive expansion / contraction buffer material 14 are included. One end of the CNF 12 is attached to the surface of the silicon-containing particles 11. The expansion / contraction buffer material 14 is interposed between the particles of the composite negative electrode active material 13. That is, one end of the conductive CNF 12 is fixed to the surface of the silicon-containing particle 11, and the other end is connected to the expansion / contraction buffer material 14. As a result, a conductive network is formed between the silicon-containing particles 11 having poor conductivity via the expansion / contraction buffer material 14.

図２（ａ）に示すように、充電すると含ケイ素粒子１１がリチウムイオンを吸蔵する。これに伴い含ケイ素粒子１１は膨張する。この膨張によるストレスを膨張収縮緩衝材１４が吸収する。これにより含ケイ素粒子１１の膨張による合剤層１Ｂの膨張が緩和される。また含ケイ素粒子１１の表面に付着されたＣＮＦ１２が膨張収縮緩衝材１４に適度に絡まることにより、複合負極活物質１３同士の間に膨張収縮緩衝材１４が均一に存在しやすくなるため、膨張収縮緩衝材１４の凝集が物理的に抑制される。   As shown in FIG. 2A, when charged, the silicon-containing particles 11 occlude lithium ions. Along with this, the silicon-containing particles 11 expand. The expansion and contraction cushioning material 14 absorbs the stress due to the expansion. Thereby, the expansion of the mixture layer 1B due to the expansion of the silicon-containing particles 11 is alleviated. Further, since the CNF 12 attached to the surface of the silicon-containing particles 11 is appropriately entangled with the expansion / contraction buffer material 14, the expansion / contraction buffer material 14 easily exists between the composite negative electrode active materials 13. Aggregation of the buffer material 14 is physically suppressed.

一方、図２（ｂ）に示すように、放電時には含ケイ素粒子１１が収縮するが、ＣＮＦ１２に絡まっている膨張収縮緩衝材１４が引っ張られて広がるので、放電時の導電性低下も抑制される。このように活物質核である含ケイ素粒子１１同士の間の導電ネットワークが保たれる。また合剤層１Ｂの膨張収縮のストレスが緩和され変形が抑制される。これによって、合剤層１Ｂと集電体１Ａとの剥離も抑制される。以上により優れたサイクル特性が得られる。   On the other hand, as shown in FIG. 2 (b), the silicon-containing particles 11 contract during discharge, but the expansion / contraction buffer material 14 entangled with the CNF 12 is pulled and spread, so that a decrease in conductivity during discharge is also suppressed. . Thus, the conductive network between the silicon-containing particles 11 which are active material nuclei is maintained. Further, the expansion / contraction stress of the mixture layer 1B is relieved and deformation is suppressed. Thereby, peeling of the mixture layer 1B and the current collector 1A is also suppressed. As a result, excellent cycle characteristics can be obtained.

膨張収縮緩衝材１４の添加量はサイクル特性と容量とに影響する。すなわち、５重量部未満であると膨張収縮の応力の吸収が不十分となる。一方、３０重量部より多くなると、合剤層１Ｂに占める含ケイ素粒子１１の割合が低くなり、容量メリットが低下する。これは膨張収縮緩衝材１４自体がリチウムイオンを吸蔵（充電）する機能がないためである。したがって膨張収縮緩衝材１４の添加量は、含ケイ素粒子１１の１００重量部当たり５重量部以上、３０重量部以下が好ましい。   The addition amount of the expansion / contraction buffer material 14 affects the cycle characteristics and capacity. That is, when the amount is less than 5 parts by weight, the absorption of the expansion and contraction stress becomes insufficient. On the other hand, when it exceeds 30 parts by weight, the proportion of the silicon-containing particles 11 in the mixture layer 1B is reduced, and the capacity merit is lowered. This is because the expansion / contraction buffer material 14 itself does not have a function of occluding (charging) lithium ions. Accordingly, the addition amount of the expansion / contraction buffer material 14 is preferably 5 parts by weight or more and 30 parts by weight or less per 100 parts by weight of the silicon-containing particles 11.

以下、具体的な実験とその結果を用い本発明の特徴と効果について説明する。まず正極２の作製について説明する。正極活物質としてＬｉＮｉ０．８Ｃｏ０．２Ｏ２粉末８５重量部と、導電剤のアセチレンブラック１０重量部、結着剤としてＰＶＤＦを固形分として５重量部とを混合し、これらを脱水したＮ−メチル−２−ピロリドン（ＮＭＰ）に分散させてスラリー状の正極合剤スラリーを調整した。このスラリーを厚み２０μｍのＡｌ箔からなる集電体２Ａの両面に塗布し、乾燥後圧延して合剤層２Ｂを形成し、所定の寸法に切断後、集電体２Ａの露出部分にＡｌ製のリード２Ｃを溶接あるいは超音波溶着により取付け、正極２を作製した。 The features and effects of the present invention will be described below using specific experiments and results. First, preparation of the positive electrode 2 will be described. 85 parts by weight of LiNi 0.8 Co 0.2 O 2 powder as a positive electrode active material, 10 parts by weight of acetylene black as a conductive agent, and 5 parts by weight of PVDF as a solid content as a binder were mixed and dehydrated. A slurry-like positive electrode mixture slurry was prepared by dispersing in N-methyl-2-pyrrolidone (NMP). This slurry is applied to both sides of a current collector 2A made of an Al foil having a thickness of 20 μm, dried and rolled to form a mixture layer 2B, cut to a predetermined size, and then made of Al on the exposed portion of the current collector 2A. The lead 2C was attached by welding or ultrasonic welding to produce the positive electrode 2.

次に負極１の作製について説明する。サンプル１では、含ケイ素粒子１１としてＳｉＯを用いた。ＳｉＯをあらかじめ粉砕して、粒径１０μm以下にし、これを１００重量部と硝酸ニッケル（ＩＩ）六水和物１重量部とをイオン交換水を溶媒として混合した。これを1時間撹拌した後、エバポレータ装置で溶媒を除去し、乾燥させて、ＳｉＯの粒子表面に硝酸ニッケルを担持させた。この粒子をＳＥＭで分析した結果、硝酸ニッケル（ＩＩ）が含ケイ素粒子表面に析出しているのを確認した。   Next, preparation of the negative electrode 1 will be described. In Sample 1, SiO was used as the silicon-containing particles 11. SiO was pulverized in advance to a particle size of 10 μm or less, and 100 parts by weight of this and 1 part by weight of nickel (II) nitrate hexahydrate were mixed using ion-exchanged water as a solvent. After stirring this for 1 hour, the solvent was removed with an evaporator and dried to support nickel nitrate on the SiO particle surfaces. As a result of analyzing the particles by SEM, it was confirmed that nickel nitrate (II) was deposited on the surface of the silicon-containing particles.

硝酸ニッケルを担持したＳｉＯをセラミックス製反応容器に投入し、ヘリウムガス中で５５０℃まで昇温させた後、水素ガス５０％とエチレン５０％の混合ガスに置換して５５０℃で１時間保持し、硝酸ニッケル（ＩＩ）を還元するとともに、含ケイ素粒子１１の表面に先端が付着したＣＮＦ１２を成長させた。その後、混合ガス中７００℃で１時間保持してＣＮＦ１２を熱処理し、複合負極活物質１３を得た。   SiO loaded with nickel nitrate is put into a ceramic reaction vessel, heated to 550 ° C. in helium gas, then replaced with a mixed gas of 50% hydrogen gas and 50% ethylene and held at 550 ° C. for 1 hour. Then, nickel nitrate (II) was reduced, and CNF 12 having tips attached to the surface of the silicon-containing particles 11 was grown. Then, CNF12 was heat-processed by hold | maintaining at 700 degreeC in mixed gas for 1 hour, and the composite negative electrode active material 13 was obtained.

得られた複合負極活物質１３をＳＥＭで分析した結果、ＳｉＯの粒子表面に繊維径８０ｎｍ程度のＣＮＦ１２が無数に成長していることが確認された。成長したＣＮＦ１２の重量は、ＳｉＯの１００重量部に対して２５重量部であった。   As a result of analyzing the obtained composite negative electrode active material 13 by SEM, it was confirmed that an infinite number of CNFs 12 having a fiber diameter of about 80 nm grew on the surface of the SiO particles. The weight of the grown CNF 12 was 25 parts by weight with respect to 100 parts by weight of SiO.

次に、複合負極活物質１３を１００重量部と、膨張収縮緩衝材１４としてストラクチャ構造のアセチレンブラックを２０重量部とを乾式混合した。さらに増粘剤としてカルボキシメチルセルロース３重量部、結着剤としてポリスチレンブタジエンを固形分換算で１０重量部を加え、イオン交換水を加えながらフェニキュラー状態にならないように混合してペースト状の負極合剤スラリーを調整した。このスラリーを厚み１５μｍの銅箔からなる集電体１Ａの両面に塗布し、乾燥後圧延して合剤層１Ｂを形成し、所定の寸法に切断後、集電体１Ａの露出部分にニッケル製のリード１Ｃを超音波溶着により取付け、負極１を作製した。   Next, 100 parts by weight of the composite negative electrode active material 13 and 20 parts by weight of acetylene black having a structure structure as the expansion / contraction buffer material 14 were dry mixed. Furthermore, 3 parts by weight of carboxymethylcellulose as a thickener, 10 parts by weight of polystyrene butadiene as a binder are added in solid form, and mixed so as not to become a phencular state while adding ion-exchanged water. The slurry was adjusted. This slurry is applied to both surfaces of a current collector 1A made of a copper foil having a thickness of 15 μm, dried and rolled to form a mixture layer 1B, cut to a predetermined size, and then made of nickel on the exposed portion of the current collector 1A. The lead 1C was attached by ultrasonic welding, and the negative electrode 1 was produced.

以上のようにして作製した正極２、負極１を用い次のようにして非水電解質二次電池を作製した。すなわち、正極２と負極１との間に厚み２０μｍ、多孔度約４０％のポリエチレン製微多孔膜をセパレータ３として挟み、捲回して発電要素を構成した。この発電要素を直径１８ｍｍ、高さ６５ｍｍのケース４に収納し、リード１Ｃをケース４の底部に溶接するとともに、リード２Ｃを封口板５の金属部分５Ｂに溶接した。   Using the positive electrode 2 and the negative electrode 1 produced as described above, a nonaqueous electrolyte secondary battery was produced as follows. That is, a polyethylene microporous film having a thickness of 20 μm and a porosity of about 40% was sandwiched between the positive electrode 2 and the negative electrode 1 as a separator 3 and wound to form a power generation element. The power generation element was housed in a case 4 having a diameter of 18 mm and a height of 65 mm, the lead 1C was welded to the bottom of the case 4, and the lead 2C was welded to the metal portion 5B of the sealing plate 5.

次にエチレンカーボネート（ＥＣ）とエチルメチルカーボネート（ＥＭＣ）との混合溶媒（重量比３：７）に１．０ｍｏｌ／ｄｍ３の濃度でＬｉＰＦ６を溶解した電解液を６ｇ注入し、減圧して電解液を発電要素の内部に浸透させた。最後に封口板５を機械的にかしめてケース４を密閉し、円筒型非水電解質二次電池を作製した。このようにして作製した電池について０．７ＣｍＡの定電流で４．１Ｖまで充電し、０．７ＣｍＡの定電流で２．５Ｖまで放電する充放電を２度行い、さらに４５℃環境で７日間保存した。以上のようにして電池を評価前処理した。 Next, 6 g of an electrolytic solution in which LiPF 6 was dissolved at a concentration of 1.0 mol / dm 3 was injected into a mixed solvent (weight ratio 3: 7) of ethylene carbonate (EC) and ethyl methyl carbonate (EMC), and the pressure was reduced. The electrolyte was allowed to penetrate into the power generation element. Finally, the sealing plate 5 was mechanically caulked to seal the case 4 to produce a cylindrical nonaqueous electrolyte secondary battery. The battery thus manufactured is charged to 4.1 V with a constant current of 0.7 CmA, charged and discharged twice to 2.5 V with a constant current of 0.7 CmA, and further stored for 7 days in a 45 ° C. environment. did. The battery was pre-evaluated as described above.

サンプル２、３では、含ケイ素粒子１１としてそれぞれＳｉＯ０．０６、ＳｉＯ１．９４を用いたこと以外はサンプル１と同様にして負極１を作製し、それを用いて非水電解質二次電池を作製した。 In Samples 2 and 3, the negative electrode 1 was produced in the same manner as in Sample 1 except that SiO 0.06 and SiO 1.94 were used as the silicon-containing particles 11, respectively, and a non-aqueous electrolyte secondary battery was manufactured using the negative electrode 1. Produced.

サンプル４では含ケイ素粒子１１としてＳｉＯを用いるとともに、ＳｉＯに黒鉛を重量比が９：１となるように混合し、この混合粉末に、サンプル１と同様にしてＣＮＦ１２を成長させた。このようにして調整した複合負極活物質１３を用いたこと以外は、サンプル１と同様にして負極１を作製し、それを用いて非水電解質二次電池を作製した。   In sample 4, SiO was used as the silicon-containing particles 11, and graphite was mixed with SiO in a weight ratio of 9: 1. CNF12 was grown on this mixed powder in the same manner as in sample 1. A negative electrode 1 was produced in the same manner as in Sample 1 except that the composite negative electrode active material 13 prepared in this way was used, and a nonaqueous electrolyte secondary battery was produced using it.

サンプル５〜８では、膨張収縮緩衝材１４の添加量を変えた以外はサンプル１と同様にして負極１を作製し、それを用いて非水電解質二次電池を作製した。各サンプルのアセチレンブラックの添加量は、含ケイ素粒子１１であるＳｉＯの１００重量部あたりそれぞれ３、５、３０および４０重量部である。   In Samples 5 to 8, the negative electrode 1 was produced in the same manner as in the sample 1 except that the addition amount of the expansion / contraction buffer material 14 was changed, and a nonaqueous electrolyte secondary battery was produced using the negative electrode 1. The amount of acetylene black added to each sample is 3, 5, 30, and 40 parts by weight per 100 parts by weight of SiO, which is the silicon-containing particles 11, respectively.

また比較サンプルとして膨張収縮緩衝材１４であるアセチレンブラックを添加しなかったこと以外は、サンプル１と同様にして負極１を作製し、それを用いて非水電解質二次電池を作製した。   Moreover, the negative electrode 1 was produced like the sample 1 except not having added the acetylene black which is the expansion-contraction buffer material 14 as a comparative sample, and the nonaqueous electrolyte secondary battery was produced using it.

次に作製したサンプル電池の評価方法について説明する。０．７ＣｍＡの定電流で４．１Ｖまで充電したあと、４．２Ｖで保持して０．０５ＣｍＡまで電流が低下するまで充電し、０．５ＣｍＡの定電流で２．５Ｖまで放電した。このときの放電容量を初期放電容量とし、サンプル１の設計容量を基準として放電容量比を算出した。ここで０．０５ＣｍＡとは、電池設計容量を２０時間で除した電流値を意味する。   Next, a method for evaluating the produced sample battery will be described. The battery was charged to 4.1 V with a constant current of 0.7 CmA, held at 4.2 V, charged until the current decreased to 0.05 CmA, and discharged to 2.5 V with a constant current of 0.5 CmA. The discharge capacity at this time was defined as the initial discharge capacity, and the discharge capacity ratio was calculated based on the design capacity of Sample 1. Here, 0.05 CmA means a current value obtained by dividing the battery design capacity by 20 hours.

次に、初期放電容量評価と同様の条件で充電、１ＣｍＡの定電流で２．５Ｖまで放電する充放電サイクルを５０サイクル実施した。このときの１サイクル目の放電容量で５０サイクル目の放電容量を除して容量維持率を算出し、サイクル特性の指標とした。さらに充放電サイクル評価後の電池を分解して合剤層１Ｂの膨張率を顕微鏡的に測定した。各サンプルの諸元と評価結果を（表１）に示す。   Next, 50 cycles of charging and discharging were performed under the same conditions as in the initial discharge capacity evaluation, and discharging to 2.5 V at a constant current of 1 CmA. The capacity retention rate was calculated by dividing the discharge capacity at the 50th cycle by the discharge capacity at the first cycle at this time, and used as an index of the cycle characteristics. Furthermore, the battery after charge / discharge cycle evaluation was disassembled, and the expansion coefficient of the mixture layer 1B was measured microscopically. The specifications and evaluation results of each sample are shown in (Table 1).

Figure 2007165079
Figure 2007165079

（表１）より明らかなように、比較サンプルに比べるとサンプル１〜８はいずれもサイクル特性が向上している。これは膨張率の測定結果を見ても明らかなように、膨張収縮緩衝材１４の添加により合剤層１Ｂの膨張が抑制され、合剤層１Ｂ内の導電ネットワークが維持されているためと考えられる。   As apparent from (Table 1), the cycle characteristics of Samples 1 to 8 are improved compared to the comparative sample. As is apparent from the measurement result of the expansion coefficient, the expansion of the mixture layer 1B is suppressed by the addition of the expansion / shrinkage buffer material 14, and the conductive network in the mixture layer 1B is maintained. It is done.

また、サンプル１〜３を比較しても容量、サイクル特性とも大きな差はなく、含ケイ素粒子１１がＳｉＯｘの場合に、０．０５＜ｘ<１．９５のいずれの材料を用いても本発明の効果が得られることがわかる。 In addition, even when Samples 1 to 3 are compared, there is no significant difference in capacity and cycle characteristics. When the silicon-containing particles 11 are made of SiO x , this material can be used regardless of the material of 0.05 <x <1.95. It turns out that the effect of invention is acquired.

サンプル４はサンプル１に比べると、容量密度の低い黒鉛を添加した割合だけ、放電容量が低下しているが、サンプル１同様にサイクル特性が向上していることがわかる。   Compared to sample 1, sample 4 has a reduced discharge capacity by the proportion of graphite with a lower capacity density added, but it can be seen that cycle characteristics are improved as in sample 1.

サンプル１、５〜８を比較すると、膨張収縮緩衝材１４の添加量とサイクル特性とに深い関係があることがわかる。すなわち、膨張収縮緩衝材１４の添加量が３重量部のサンプル５では合剤層１Ｂの膨張率がやや大きく、そのためサイクル特性がやや低下している。一方、膨張収縮緩衝材１４の添加量が４０重量部のサンプル８では、サイクル特性が良好な反面、容量がやや小さくなっている。この結果から、含ケイ素粒子１１の１００重量部に対し、膨張収縮緩衝材１４の添加量は５重量部以上３０重量部以下であることがより好ましい。   Comparing Samples 1 and 5 to 8 reveals that there is a deep relationship between the amount of expansion / shrinkage buffer 14 added and the cycle characteristics. That is, in the sample 5 in which the addition amount of the expansion / contraction buffer material 14 is 3 parts by weight, the expansion rate of the mixture layer 1B is slightly large, and therefore the cycle characteristics are slightly deteriorated. On the other hand, in the sample 8 in which the added amount of the expansion / contraction buffer material 14 is 40 parts by weight, the cycle characteristics are good, but the capacity is slightly small. From this result, the addition amount of the expansion / contraction buffer material 14 is more preferably 5 parts by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the silicon-containing particles 11.

以上、薄型長尺の正負極を用いた捲回型電池を例に説明したが、コイン型電池に適用しても同様の効果が得られる。コイン型電池の場合、必ずしも集電体１Ａは必要なく、外部端子を兼ねる鉄、ニッケルめっきされた鉄などの金属ケースの内面に直接合剤層１Ｂを設けてもよい。また、合剤ペーストのように湿式のプロセスを用いずに、粉体の結着剤、複合負極活物質１３、膨張収縮緩衝材１４を混合し、この混合体をプレスして用いてもよい。   As described above, the winding type battery using the thin and long positive and negative electrodes has been described as an example, but the same effect can be obtained even when applied to a coin type battery. In the case of a coin-type battery, the current collector 1A is not necessarily required, and the mixture layer 1B may be provided directly on the inner surface of a metal case such as iron that also serves as an external terminal or nickel-plated iron. Further, the powder binder, the composite negative electrode active material 13 and the expansion / shrinkage buffer material 14 may be mixed and used by pressing the mixture without using a wet process as in the case of the mixture paste.

本発明に係る非水電解質二次電池用負極は、高容量を実現しつつ、サイクル特性の大幅に改善された非水電解質二次電池を提供することができる。そのため、今後増大するリチウム電池の高エネルギー密度化に寄与する。   The negative electrode for a non-aqueous electrolyte secondary battery according to the present invention can provide a non-aqueous electrolyte secondary battery with significantly improved cycle characteristics while realizing a high capacity. Therefore, it contributes to higher energy density of lithium batteries, which will increase in the future.

（ａ）本発明の実施の形態１における非水電解質二次電池の構成を示す断面図（ｂ）同部分拡大図(A) Sectional drawing which shows the structure of the nonaqueous electrolyte secondary battery in Embodiment 1 of this invention (b) The elements on larger scale （ａ）本発明を用いた負極合剤層内部の複合負極活物質粒子周囲の充電時の状態を示す模式図（ｂ）同複合負極活物質粒子周囲の放電時の状態を示す模式図(A) Schematic diagram showing a state during charging around the composite negative electrode active material particles inside the negative electrode mixture layer using the present invention (b) Schematic diagram showing a state during discharge around the composite negative electrode active material particles

符号の説明Explanation of symbols

１ 負極
１Ａ 集電体
１Ｂ 合剤層
１Ｃ リード
２ 正極
２Ａ 集電体
２Ｂ 合剤層
２Ｃ リード
３ セパレータ
４ ケース
５ 封口板
１１ 含ケイ素粒子
１２ カーボンナノファイバ（ＣＮＦ）
１３ 複合負極活物質
１４ 膨張収縮緩衝材 DESCRIPTION OF SYMBOLS 1 Negative electrode 1A Current collector 1B Mixture layer 1C Lead 2 Positive electrode 2A Current collector 2B Mixture layer 2C Lead 3 Separator 4 Case 5 Sealing plate 11 Silicon-containing particle 12 Carbon nanofiber (CNF)
13 Composite negative electrode active material 14 Expansion / shrinkage buffer material

Claims (5)

少なくともリチウムイオンの吸蔵放出が可能な含ケイ素粒子と、前記含ケイ素粒子の表面に付着されたカーボンナノファイバとからなる複合負極活物質と、
導電性を有する膨張収縮緩衝材とを含む合剤層を備えた非水電解質二次電池用負極。 A composite negative electrode active material comprising at least silicon-containing particles capable of occluding and releasing lithium ions, and carbon nanofibers attached to the surface of the silicon-containing particles;
A negative electrode for a non-aqueous electrolyte secondary battery, comprising a mixture layer including a conductive expansion / shrinkage buffer material. 前記膨張収縮緩衝材がストラクチャ構造を有するカーボンブラックであることを特徴とする請求項１記載の非水電解質二次電池用負極。 The negative electrode for a nonaqueous electrolyte secondary battery according to claim 1, wherein the expansion / contraction buffer material is carbon black having a structure structure. 前記カーボンブラックの添加量は、前記複合負極活物質１００重量部当たり５重量部以上、３０重量部以下としたことを特徴とする請求項２記載の非水電解質二次電池用負極。 The negative electrode for a non-aqueous electrolyte secondary battery according to claim 2, wherein the addition amount of the carbon black is 5 parts by weight or more and 30 parts by weight or less per 100 parts by weight of the composite negative electrode active material. 前記含ケイ素粒子がＳｉＯｘ（０．０５＜ｘ<１．９５）を含むことを特徴とする請求項１記載の非水電解質二次電池用負極。 The negative electrode for a non-aqueous electrolyte secondary battery according to claim 1, wherein the silicon-containing particles contain SiO x (0.05 <x <1.95). 請求項１〜４のいずれか１項に記載の非水電解質二次電池用負極を備えた非水電解質二次電池。 The nonaqueous electrolyte secondary battery provided with the negative electrode for nonaqueous electrolyte secondary batteries of any one of Claims 1-4.
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JP4834814B2 (en) * 2007-07-17 2011-12-14 ネグゼオン・リミテッド Method for producing structured particles composed of silicon or silicon-based materials and their use in lithium batteries
JP2011222522A (en) * 2007-07-17 2011-11-04 Nexeon Ltd Method of producing structured particles consisting of silicon or silicon based material, and use thereof in lithium storage battery
US9012079B2 (en) 2007-07-17 2015-04-21 Nexeon Ltd Electrode comprising structured silicon-based material
US8940437B2 (en) 2007-07-17 2015-01-27 Nexeon Limited Method of fabricating structured particles composed of silicon or a silicon-based material and their use in lithium rechargeable batteries
US8870975B2 (en) 2007-07-17 2014-10-28 Nexeon Ltd. Method of fabricating structured particles composed of silicon or a silicon-based material and their use in lithium rechargeable batteries
US8642211B2 (en) 2007-07-17 2014-02-04 Nexeon Limited Electrode including silicon-comprising fibres and electrochemical cells including the same
US9871244B2 (en) 2007-07-17 2018-01-16 Nexeon Limited Method of fabricating structured particles composed of silicon or a silicon-based material and their use in lithium rechargeable batteries
JP2010533637A (en) * 2007-07-17 2010-10-28 ネグゼオン・リミテッド Method for producing structured particles composed of silicon or silicon-based materials and their use in lithium batteries
JP2009272153A (en) * 2008-05-08 2009-11-19 Hitachi Maxell Ltd Lithium secondary battery
US9184438B2 (en) 2008-10-10 2015-11-10 Nexeon Ltd. Method of fabricating structured particles composed of silicon or a silicon-based material and their use in lithium rechargeable batteries
US8932759B2 (en) 2008-10-10 2015-01-13 Nexeon Ltd. Method of fabricating structured particles composed of silicon or a silicon-based material
KR101558535B1 (en) * 2008-12-02 2015-10-07 삼성전자주식회사 Negative active material negative electrode comrprising same method of preparing negative electrodee and lithium battery
US20100159331A1 (en) * 2008-12-23 2010-06-24 Samsung Electronics Co., Ltd. Negative active material, negative electrode including the same, method of manufacturing the negative electrode, and lithium battery including the negative electrode
US8608983B2 (en) 2009-01-30 2013-12-17 Samsung Electronics Co., Ltd. Composite anode active material, anode including the composite anode active material, lithium battery including the anode, and method of preparing the composite anode active material
US9178212B2 (en) 2009-01-30 2015-11-03 Samsung Electronics Co., Ltd. Composite anode active material, anode including the composite anode active material, lithium battery including the anode, and method of preparing the composite anode active material
US9553304B2 (en) 2009-05-07 2017-01-24 Nexeon Limited Method of making silicon anode material for rechargeable cells
US8962183B2 (en) 2009-05-07 2015-02-24 Nexeon Limited Method of making silicon anode material for rechargeable cells
US9853292B2 (en) 2009-05-11 2017-12-26 Nexeon Limited Electrode composition for a secondary battery cell
US9608272B2 (en) 2009-05-11 2017-03-28 Nexeon Limited Composition for a secondary battery cell
US10050275B2 (en) 2009-05-11 2018-08-14 Nexeon Limited Binder for lithium ion rechargeable battery cells
EP3859830A1 (en) * 2009-05-19 2021-08-04 OneD Material, Inc. Nanostructured materials for battery applications
EP2433475A4 (en) * 2009-05-19 2014-04-16 Nanosys Inc Nanostructured materials for battery applications
KR102067922B1 (en) * 2009-05-19 2020-01-17 원드 매터리얼 엘엘씨 Nanostructured materials for battery applications
WO2010135446A1 (en) 2009-05-19 2010-11-25 Nanosys, Inc. Nanostructured materials for battery applications
US11600821B2 (en) 2009-05-19 2023-03-07 Oned Material, Inc. Nanostructured materials for battery applications
US10490817B2 (en) 2009-05-19 2019-11-26 Oned Material Llc Nanostructured materials for battery applications
KR20190002755A (en) * 2009-05-19 2019-01-08 원드 매터리얼 엘엘씨 Nanostructured materials for battery applications
US11233240B2 (en) 2009-05-19 2022-01-25 Oned Material, Inc. Nanostructured materials for battery applications
EP4068914A3 (en) * 2009-05-19 2022-10-12 OneD Material, Inc. Nanostructured materials for battery applications
KR101935416B1 (en) 2009-05-19 2019-01-07 원드 매터리얼 엘엘씨 Nanostructured materials for battery applications
EP2433475A1 (en) * 2009-05-19 2012-03-28 Nanosys, Inc. Nanostructured materials for battery applications
JP5527317B2 (en) * 2009-05-28 2014-06-18 日産自動車株式会社 Negative electrode for lithium ion secondary battery and battery using the same
US8927149B2 (en) 2009-05-28 2015-01-06 Nissan Motor Co., Ltd. Negative electrode for lithium ion secondary battery and battery using same
US20120094181A1 (en) * 2009-06-18 2012-04-19 Unist Academy-Industry Research Corporation Cathode Active Material For A Lithium Rechargeable Battery And A Production Method Therefor
US9391321B2 (en) * 2009-06-18 2016-07-12 Lg Chem, Ltd. Negative-electrode active material for lithium secondary battery and method of preparing the same
CN102612769A (en) * 2009-09-23 2012-07-25 尤米科尔公司 New silicon based electrode formulations for lithium-ion batteries and method for obtaining it
KR101383473B1 (en) * 2009-09-23 2014-04-08 유미코르 New silicon based electrode formulations for lithium-ion batteries and method for obtaining it
JP2013505547A (en) * 2009-09-23 2013-02-14 ユミコア ソシエテ アノニム New silicon-based electrode formulations for lithium ion batteries and methods for obtaining the formulations
CN102576859A (en) * 2009-09-25 2012-07-11 株式会社丰田自动织机 Negative electrode for lithium-ion secondary battery, and manufacturing process for the same
JP2011070892A (en) * 2009-09-25 2011-04-07 Toyota Industries Corp Negative electrode for lithium ion secondary battery, and method of manufacturing the same
EP2482369A4 (en) * 2009-09-25 2014-08-06 Toyota Jidoshokki Kk Anode for use in a lithium-ion secondary battery, and manufacturing method therefor
US8822083B2 (en) 2009-09-25 2014-09-02 Kabushiki Kaisha Toyota Jidoshokki Negative electrode for lithium-ion secondary battery and manufacturing process for the same
EP2482369A1 (en) * 2009-09-25 2012-08-01 Kabushiki Kaisha Toyota Jidoshokki Anode for use in a lithium-ion secondary battery, and manufacturing method therefor
KR101294228B1 (en) 2009-09-25 2013-08-07 가부시키가이샤 도요다 지도숏키 Negative electrode for lithium-ion secondary battery and manufacturing process for the same
WO2011037013A1 (en) * 2009-09-25 2011-03-31 株式会社豊田自動織機 Anode for use in a lithium-ion secondary battery, and manufacturing method therefor
JP2011113863A (en) * 2009-11-27 2011-06-09 Hitachi Maxell Ltd Nonaqueous secondary battery
US8772174B2 (en) 2010-04-09 2014-07-08 Nexeon Ltd. Method of fabricating structured particles composed of silicon or silicon-based material and their use in lithium rechargeable batteries
US9368836B2 (en) 2010-06-07 2016-06-14 Nexeon Ltd. Additive for lithium ion rechargeable battery cells
US8945774B2 (en) 2010-06-07 2015-02-03 Nexeon Ltd. Additive for lithium ion rechageable battery cells
US9647263B2 (en) 2010-09-03 2017-05-09 Nexeon Limited Electroactive material
US9947920B2 (en) 2010-09-03 2018-04-17 Nexeon Limited Electroactive material
US9871248B2 (en) 2010-09-03 2018-01-16 Nexeon Limited Porous electroactive material
JP2012169300A (en) * 2012-06-06 2012-09-06 Hitachi Maxell Energy Ltd Nonaqueous secondary battery
US9637136B2 (en) 2012-11-14 2017-05-02 Swift Tram, Inc. Suspended coach transit system
JP2015088450A (en) * 2013-09-26 2015-05-07 積水化学工業株式会社 Lithium ion secondary battery
CN106794994A (en) * 2014-08-27 2017-05-31 株式会社丰田自动织机 The manufacture method of the coated silicon materials of carbon
CN106794994B (en) * 2014-08-27 2019-08-16 株式会社丰田自动织机 Carbon is coated the manufacturing method of silicon materials
JP2016162548A (en) * 2015-02-27 2016-09-05 旭カーボン株式会社 Electrode active material, electrode for secondary battery and secondary battery
CN107251289A (en) * 2015-02-27 2017-10-13 旭碳株式会社 Electrode active material, electrode for secondary battery and secondary cell
WO2016135783A1 (en) * 2015-02-27 2016-09-01 旭カーボン株式会社 Electrode active material, electrode for secondary batteries, and secondary battery
CN107251289B (en) * 2015-02-27 2020-07-28 旭碳株式会社 Electrode active material covered with carbonaceous material, electrode for secondary battery, and secondary battery
CN112673499A (en) * 2018-09-26 2021-04-16 松下知识产权经营株式会社 Positive electrode for secondary battery and secondary battery
US11430993B2 (en) 2019-02-08 2022-08-30 Sanyo Electric Co., Ltd. Electrode of nonaqueous electrolyte secondary battery, nonaqueous electrolyte secondary battery, method for producing electrode, and method for producing nonaqueous electrolyte secondary battery
JP7169217B2 (en) 2019-02-08 2022-11-10 三洋電機株式会社 Electrode for non-aqueous electrolyte secondary battery, non-aqueous electrolyte secondary battery, and manufacturing method thereof
JP2020129472A (en) * 2019-02-08 2020-08-27 三洋電機株式会社 Electrode of nonaqueous electrolyte secondary battery, nonaqueous electrolyte secondary battery and manufacturing methods thereof
JP2020136075A (en) * 2019-02-20 2020-08-31 トヨタ自動車株式会社 Production method of negative electrode active material
JP7147619B2 (en) 2019-02-20 2022-10-05 トヨタ自動車株式会社 Method for producing negative electrode active material
JP2022546527A (en) * 2019-09-30 2022-11-04 エルジー エナジー ソリューション リミテッド Composite negative electrode active material, manufacturing method thereof, and negative electrode including the same
US11891523B2 (en) 2019-09-30 2024-02-06 Lg Energy Solution, Ltd. Composite negative electrode active material, method of manufacturing the same, and negative electrode including the same
JP7451012B2 (en) 2019-09-30 2024-03-18 エルジー エナジー ソリューション リミテッド Composite negative electrode active material, its manufacturing method, and negative electrode containing the same

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