Matsushita Electric Industrial Co., Ltd.

Other

Panasonic Corporation

Sumitomo Metal Industries, Inc.

Panasonic Intellectual Property Management Co., Ltd.

Yoshiaki Nitta

Harunari Shimamura

Kazuhiro Okamura

Hiroshi Yoshizawa

Shinji Kasamatsu

Yasuhiko Bito

Hizuru Koshina

Toshitada Sato

Takayuki Shirane

Akira Miura

Takayuki Nakamoto

Sachiko Sugihara

Kazuya Iwamoto

Masaki Hasegawa

Masatoshi Nagayama

Noriyuki Negi

Shuji Tsutsumi

Hideya Kaminaka

Katsuhiro Takahashi

Junichi Yamaura

Masaru Abe

Tsuyoshi Hatanaka

Kaoru Inoue

Takuya Ishii

Hiroyuki Handa

Takuya Nakashima

Shoichiro Watanabe

Shigeo Kobayashi

Kenichi Morigaki

Kazunori Haraguchi

Tooru Fuse

Shinji Arimoto

Yasufumi Nakajima

Takafumi Fujiwara

Akira Ohta

Miho Kayama

Hiroki Muraoka

Hideharu Satou

Keiko Nishioka

Tomoaki Seo

A negative electrode material for non-aqueous electrolyte secondary batteries, characterized in that the negative electrode material comprises a composite particle including solid phases A and B, the solid phase A being dispersed in the solid phase B, and the ratio (I/I) of the maximum diffracted X-ray intensity (I) attributed to the solid phase A to the maximum diffracted X-ray intensity (I) attributed to the solid phase B satisfies 0.001&#x2266;I/I&#x2266;0.1, in terms of a diffraction line obtained by a wide-angle X-ray diffraction measurement of the composite particle.

Cathode material and non-aqueous electrolyte secondary battery using it

To present a nonaqueous electrolyte secondary battery using iron compound which is inexpensive and abundant in resource, as the active material for the positive electrode. An iron compound with particle size of 1 to 300 nm or less, being composed of substantially spherical primary particles of pore-free matter, is used as the active material for a positive electrode, which is used together with a negative electrode and a nonaqueous electrolyte for composing the battery. By forming the primary particles for composing particles of the iron compound as a pore-free matter, being controlled in a range of 1 to 300 nm, nano effects are brought about, and it is also effective to suppress excessive increase of surface area which may lead to promotion of decomposition of electrolyte, and an excellent discharge capacity is realized stably for a long period.

Nonaqueous electrolyte battery

A non-aqueous electrolyte secondary battery provided with a positive electrode having a lithium-manganese composite oxide as a positive electrode material, a negative electrode comprising a material capable of absorbing and releasing lithium and a non-aqueous electrolyte can be inhibited from deterioration of the negative electrode and can maintain excellent battery performances even after stored in a high-temperature environment or subjected to charging and discharging cycles at high temperatures by containing at least one of sodium (Na), potassium (K), calcium (Ca) and strontium (Sr).

Non-aqueous electrolyte secondary battery

When the composite particle containing Si or Sn is used for the negative electrode, the ratio of the median diameter 'Dc' of the conductive material to the median diameter 'Da' of the negative electrode material (Dc/Da) is made from 0.02 to 0.5 in order to improve reduction in electron conductivity, which is attributed to fine division of the particles due to repeated charge/discharge.

The present invention provides a battery-driven electronic device for which a long time use of the battery can be achieved and mobile communications equipment such as a portable telephone. Even if the time at which the output voltage of a batterybecomes below the supply voltage required by a loadincluding a power amplifier for wireless communications comes earlier than a conventional lithium ion battery because of its discharge characteristics that the battery voltage change ratio is 0.25 or more, a step-up and -down converteroperates as follows. When the output voltage of the battery is higher than the supply voltage required by the load, the voltage is set to a predetermined supply voltage by the step-down operation mode. When the output voltage of the battery is decreased and becomes lower than the supply voltage required by the load, the voltage is set to a predetermined supply voltage by the step-up operation mode. Thus, even for a battery employing a new material having a high energy density, a long term use of the battery can be achieved.

Battery-driven electronic device and mobile communication apparatus

A negative electrode material for a nonaqueous electrolyte secondary battery having a high discharge capacity and a good cycle life is made from alloy particles having an average particle diameter of 0.1-50 &#x3bc;m and including Si phase grainsand a phase of a solid solution or an intermetallic compound of Si and other element selected from Group 2A elements, transition elements, Group 3B elements, and Group 4B elements from the long form periodic table (for example, an NiSiphaseand an [NiSi+NiSi] phase) at least partially enveloping the Si phase grains. 5-99 wt % of this material is Si phase grains. The alloy particles can be manufactured by rapid solidification (such as atomization or roller quenching) of a melt including Si and the other element, or by adhering the other element to Si powder by electroless plating or mechanical alloying and then performing heat treatment. Even if rapid solidification is carried out, a negative electrode material having a good discharge capacity and cycle life is obtained without heat treatment.

Process for manufacture of negative electrode material for a non-aqueous electrolyte secondary battery

A negative electrode material for a nonaqueous electrolyte secondary battery having a high discharge capacity and a good cycle life is made from alloy particles having an average particle diameter of 0.1-50 &mgr;m and including Si phase grains 40 and a phase of a solid solution or an intermetallic compound of Si and other element selected from Group 2A elements, transition elements, Group 3B elements, and Group 4B elements from the long form periodic table (for example, an NiSi phase 42 and an &lsqb;NiSi &plus;NiSi&rsqb; phase 41) at least partially enveloping the Si phase grains. 5-99 wt % of this material is Si phase grains. The alloy particles can be manufactured by rapid solidification (such as atomization or roller quenching) of a melt including Si and the other element, or by adhering the other element to Si powder by electroless plating or mechanical alloying and then performing heat treatment. Even if rapid solidification is carried out, a negative electrode material having a good discharge capacity and cycle life is obtained without heat treatment.

Negative electrode material for a non-aqueous electrolyte secondary battery and processes for its manufacture

The present invention relates to a non-aqueous electrolyte secondary battery. The negative electrode of the present invention is characterized by its composite particles constructed in such a manner that at least part of the surrounding surface of nuclear particles containing at least one of tin, silicon and zinc as a constituent element, is coated with a solid solution or an intermetallic compound, which are composed of the element contained in the nuclear particles, and at least one other element except the elements contained in the nuclear particles selected from a group comprising group 2 elements, transition elements, group 12 elements, group 13 elements and group 14 elements except carbon of the Periodic Table. The electrolyte uses anion lithium salts of organic acid dissolved in organic solvent with high oxidation resistant characteristics. By adopting the above construction, a battery which generates only a small amount of gas during a high temperature storing can be obtained. Furthermore, the batteries enjoy high energy density and a lower reduction rate of discharge capacity when used repeatedly as well as high charge/discharge properties.

Non-aqueous electrolyte secondary battery comprising composite particles

A negative electrode of a non-aqueous electrolyte secondary battery contains, as main a component, composite particles constructed in such a manner that at least part of the surface of nuclear particles comprising at least one of tin, silicon and zinc as a constituent element, is coated with a solid solution or an inter-metallic compound composed of elements included in the nuclear particle and at least one element, exclusive of the element included in said nuclear particle, selected from a group of elements in a Periodic Table, comprising group 2 elements, transition elements, group 12 elements, group 13 elements and group 14 elements exclusive of carbon. The batteries of the present invention include non-aqueous electrolytic solution and solid electrolytes comprising polymer gel electrolytes. The construction of the present invention provides a non-aqueous electrolytic secondary battery with which a possibility of the generation of gas is extremely low when stored at high temperatures. It also provides a battery having higher capacity, and superior cycle properties, high-rate charge/discharge properties.

Non-Aqueous electrolyte secondary battery comprising composite particles

A lithium-containing composite nitride with an alkaline metal or an alkaline earth metal added thereto is used as the negative electrode active material, or used as surface layers of core particles of a lithium-containing composite nitride, to provide a negative electrode material for a nonaqueous electrolyte secondary battery with large capacity and high reliability improved in oxidation and decomposition resistance property and thus capacity recovery property after overdischarge.

Negative electrode material for nonaqueous electrolyte secondary battery and method for producing the same

A non-aqueous electrolyte secondary battery containing an alloy particle capable of absorbing and desorbing lithium in the negative electrode has a short cycle life and is insufficient in high-rate discharge characteristics, since the alloy particle is pulverized during charge/discharge cycles. In order to solve this problem, a negative electrode is employed, which comprises an alloy particle containing: at least two selected from the group consisting of metal elements and semimetal elements; oxygen; and nitrogen. It is preferred that the alloy particle have a phase A capable of electrochemically absorbing and desorbing lithium ion and a phase B having lithium ion conductivity or lithium ion permeability and that the phase B contain larger amounts of oxygen and nitrogen than the phase A.

Non-aqueous electrolyte secondary cell

A non-aqueous electrolyte secondary battery using composite particles for its negative electrode. In the composite particles, nucleus particles including at least one element selected from tin, silicon, and zinc as their constituent element are entirely or partly covered with a solid solution or inter-metallic compound of said constituent element and at least one element selected from groups consisting of Group 2 elements, transition elements, and Group 12, Group 13, and Group 14 elements in the Periodic Table except for the constituent element of the nucleus particles and carbon. Further, the present invention is characterized in that the NMR signals of the lithium intercalated in the composite particles appear within the range of &minus;10 to 40 ppm with respect to lithium chloride and at least one signal appears within the range of &minus;10 to 4 ppm.

A non-aqueous electrolyte secondary battery comprises a positive electrode and a negative electrode capable of intercalating and de-intercalating lithium, a non-aqueous electrolyte and separators or solid electrolytes. The negative electrode contains, as a main component, composite particles constructed in such a manner that at least part of the surface of nuclear particles comprising at least one of tin, silicon and zinc as a constituent element, is coated with a solid solution or an inter-metallic compound composed of the element included in the nuclear particles and another predetermined element which is not an element included in the nuclear particles. To improve the ability of the battery, the composite particles mentioned above can include at least one trace element selected from iron, lead and bismuth. The porosity of a mixture layer at the negative electrode is 10% or more and 50% or less. The amount of the non-aqueous electrolyte, the thickness of the separators or the like is restricted in a specific value. The foregoing construction suppresses occurrence of an internal short circuit between the positive electrode and the negative electrode caused by expansion of the negative electrode materials, thereby achieving a high capacity battery with a superior charge/discharge cycle properties, which is suitable for a high-speed charging.

The present invention provides a rechargeable negative electrode for a non-aqueous electrolyte secondary battery comprising an alloy material which absorbs lithium during charge and desorbs lithium during discharge, and having a long cycle life. The negative electrode includes an alloy having a hexagonal closest packing structure and a Ni In type structure composed of at least two elements.

Growing community of inventors

Hirakata, Japan

Yoshiaki Nitta