Sanyo Electric Co., Ltd.

Keisuke Minami

Toyoki Fujihara

Toshiyuki Nohma

Naoya Nakanishi

Masashi Muraoka

Yasuhiro Yamauchi

Masao Inoue

Junichi Yogo

Yohei Tao

Yukari Kuratomi

Tetsuya Matsuda

Naoki Ogawa

Daisuke Ikeda

Atsushi Yanai

Tetsuya Okado

Tomoharu Arai

Kazuki Takeno

Ken Kaneko

Yuji Ogishima

Mio Nosaka

Each prismatic cell is provided with a rolled electrode assembly, and the rolled electrode assembly has a flat section with a flat outer peripheral surface and two curved sections with a curved outer peripheral surface. Each spacer has a substrate and multiple ribs protruding on at least one side of the substrate, and the ribs are formed so as to face the flat section of the rolled electrode assembly and extend in a direction substantially perpendicular to the rolling axis of the rolled electrode assembly. The ribs have a length of 60 to 100 when the height of the flat section of the rolled electrode assembly is represented by 100, and the relationship 2≤B/A≤10 is satisfied where A is the width of the ribs and B is the distance between adjoining ribs.

Battery pack

Provided is a non-aqueous electrolyte secondary battery having excellent properties even at low temperatures. The non-aqueous electrolyte secondary battery comprises: an electrode assembly including a positive electrode plate and a negative electrode plate; a non-aqueous electrolyte; an exterior body having an opening, and accommodating the electrode assembly and the non-aqueous electrolyte; and a sealing plate for sealing the opening of the exterior body, wherein the negative electrode plate has a negative electrode core and a negative electrode active material layer formed on the negative electrode core, and the non-aqueous electrolyte contains a non-aqueous solvent, the non-aqueous solvent containing 50-80 vol % of a chain carbonate with respect to the non-aqueous solvent, and containing, as the chain carbonate, 30-40 vol % of dimethyl carbonate, 3-8 vol % of propylene carbonate, and 2-5 vol % of methyl propionate with respect to the non-aqueous solvent.

Non-aqueous electrolyte secondary battery

A non-aqueous electrolyte secondary battery including a positive electrode core; a positive electrode plate having a positive electrode active material layer formed on the positive electrode core; a negative electrode plate; a flat wound electrode assembly in which the positive electrode plate and the negative electrode plate are wound with a separator therebetween; and a non-aqueous electrolyte, wherein the positive electrode active material is a manganese-containing lithium transition metal composite oxide, the BET specific surface area of the positive electrode active material is 2.0-3.0 m/g, the total surface area of the positive electrode active material contained in the positive electrode active material layer is 70-90 m, and the value of A/B is 0.03-0.09 (μmol/m), where A (μmol) is the total amount of FSOcontained in the non-aqueous electrolyte, and B (m) is the total area of the positive electrode active material contained in the positive electrode active material layer.

Non-aqueous electrolyte secondary battery and method for manufacturing same

A nonaqueous electrolyte secondary battery according to an embodiment of the present disclosure includes a separator which contains a first region located in a flat part of an electrode body and second regions located in a pair of curved parts, the ratio (B/A) of the air permeability (B) in each of the second regions to the air permeability (A) in the first region being 0.5 or more and 0.9 or less. Further, in a section passing through the center in the axial direction of the electrode body and being perpendicular to the axial direction, the ratio (SB/SA) of the sectional area (SB) of the pair of curved parts to the sectional area (SA) of the flat part is 0.28 or more and 0.32 or less.

Nonaqueous electrolyte secondary battery

A nonaqueous electrolyte secondary battery according to an embodiment of the present disclosure includes a negative electrode mixture layer which contains a first region located in a flat part of an electrode body and second regions located in a pair of curved parts of the electrode body, the ratio (B/A) of the packing density (B) in each of the second regions to the packing density (A) in the first region being 0.75 or more and 0.95 or less. Further, in a section passing through the center in the axial direction of the electrode body and being perpendicular to the axial direction, the ratio (SB/SA) of the sectional area (SB) of the pair of curved parts to the sectional area (SA) of the flat part is 0.28 or more and 0.32 or less.

A method for manufacturing a nonaqueous electrolyte secondary battery which includes an electrode assembly, a housing with an opening and contains the electrode assembly, and a sealing member sealing the opening, the electrode assembly comprising a positive electrode and a negative electrode. The positive electrode includes a positive electrode active material, lithium carbonate, and lithium phosphate, the negative electrode comprising a negative electrode active material. The method includes placing the electrode assembly in the housing, and placing a nonaqueous electrolyte containing lithium fluorosulfonate in the housing.

Nonaqueous electrolyte secondary battery and method for manufacturing the same

A battery pack includes a plurality of prismatic secondary batteries with spacers each interposed therebetween. The prismatic secondary batteries each include a flat wound electrode body that is formed by winding a positive electrode plate and a negative electrode plate with a separator interposed therebetween; a prismatic outer body that houses the wound electrode body; and a sealing plate that seals an opening of the flat wound electrode body. The wound electrode body has a wound positive electrode core-exposed portion at one end portion and a wound negative electrode core-exposed portion at the other end portion. A positive electrode current collector is joined to the positive electrode core-exposed portion to form a positive electrode-joined portion, and a negative electrode current collector is joined to the negative electrode core-exposed portion to form a negative electrode-joined portion.

A nonaqueous electrolyte secondary battery includes a prismatic housing having an opening and a sealing member sealing the opening. The prismatic housing contains a flat-wound electrode assembly and a nonaqueous electrolyte. The flat-wound electrode assembly includes a positive electrode and a negative electrode. The positive electrode includes a positive electrode substrate and a positive electrode active material mixture layer formed on the positive electrode substrate. The positive electrode active material mixture layer contains lithium carbonate and lithium phosphate. The nonaqueous electrolyte contains lithium fluorosulfonate.

A nonaqueous electrolyte secondary battery includes a pressure-sensitive current interrupt mechanism, and a flat wound electrode body that is inserted in an outer casing with a winding axis of the flat wound electrode body arranged to extend in a horizontal direction. A positive electrode plate, a negative electrode plate, and a separator in a winding end portion of the flat wound electrode body are all directed toward a top side.

A nonaqueous electrolyte secondary battery includes: an electrode assembly including positive and negative electrode plates; a nonaqueous electrolyte; an outer body; and a current interruption mechanism being provided on at least one of a conductive pathway between the positive electrode plate and a positive electrode external terminal and a conductive pathway between the negative electrode plate and a negative electrode external terminal. The nonaqueous electrolyte contains an overcharge inhibitor. The positive electrode active material layer has a specific surface area of 1.3 m/g or less. The positive electrode active material layer has a total surface area of 41 m/g or less with respect to the total mass of the overcharge inhibitor in the nonaqueous electrolyte. Thus the battery can increase a battery internal pressure inside the outer body in a short period of time to activate the current interruption mechanism to interrupt the conductive pathway if the battery is overcharged.

A nonaqueous electrolyte secondary battery according to an embodiment of the present invention includes an electrode assembly, a nonaqueous electrolyte, and a container. The electrode assembly has a positive electrode, a negative electrode, and a separator. The positive electrode contains particles of a lithium transition metal compound as a positive electrode active material. The negative electrode is opposed to the positive electrode. The separator is disposed between the positive electrode and the negative electrode. The nonaqueous electrolyte contains lithium difluorophosphate. The container houses the electrode assembly and the nonaqueous electrolyte. The battery capacity is not less than 21 Ah. The mean particle diameter (D) of the particles of the lithium transition metal compound is not less than 5 &#x3bc;m and not more than 15 &#x3bc;m. The (D&#x2212;D)/Dof the particles of the lithium transition metal compound is under 1.1.

A positive electrode plate for a nonaqueous electrolyte secondary battery, the positive electrode plate including: a positive electrode substrate; a positive electrode active material layer formed on the positive electrode substrate; and a positive electrode substrate exposed portion on which the positive electrode active material layer is not formed, the positive electrode substrate exposed portion having a region that is adjacent to the positive electrode active material layer and has a protective layer formed thereon, the positive electrode active material layer and the protective layer containing polyvinylidene fluoride, and the weight average molecular weight Mw of the polyvinylidene fluoride contained in the protective layer being larger than the weight average molecular weight Mw of the polyvinylidene fluoride contained in the positive electrode active material layer. Thus, a high reliable nonaqueous electrolyte secondary battery where the widths of the positive electrode material and the protective layers are stable can be provided.

Positive electrode plate for nonaqueous electrolyte secondary battery, method for manufacturing the positive electrode plate, nonaqueous electrolyte secondary battery, and method for manufacturing the battery

Provided is a method of manufacturing a nonaqueous electrolyte secondary battery. The method includes: forming an electrode assembly including a positive electrode plate and a negative electrode plate disposed with a separator interposed therebetween; arranging the electrode assembly and a nonaqueous electrolyte containing LiBOB (lithium bis(oxalato)borate) and LiPFO(lithium difluorophosphate) inside an outer body; and configuring the concentration of the LiBOB to be larger than that of the LiPFOand to be smaller than that of the LiPFOby charge and discharge.

Method of manufacturing nonaqueous electrolyte secondary battery

The non-aqueous electrolyte secondary cell comprises a positive electrode having a positive electrode active material composed of a lithium transition metal composite oxide, a negative electrode having a negative electrode active material composed of carbon material, a non-aqueous electrolyte solution, and an outer body in which the positive electrode, the negative electrode and the non-aqueous electrolyte solution are housed; the mass of the non-aqueous electrolyte solution per cell capacity of the non-aqueous electrolyte secondary cell is 10.0 to 12.0 g/Ah; and the volume of the non-aqueous electrolyte solution per void volume in the outer body is 70 to 85%.

Non-aqueous electrolyte secondary cell

A nonaqueous electrolyte secondary battery of the present invention includes a positive electrode platehaving an uncoated part along at least one long side of a continuous positive electrode substratecoated with a positive electrode mixture layercontaining a positive electrode active material. In the nonaqueous electrolyte secondary battery, the positive electrode mixture layerincludes a lithium transition-metal compound capable of insertion and separation of lithium ion and 5 to 15% by mass of a conductive material with respect to the positive electrode mixture, the conductive material contains 70% by mass or more of flaked graphite particles with an average particle diameter (D) of 5 to 30 &#x3bc;m and an average thickness of 0.1 to 1.0 &#x3bc;m with respect to the whole amount of the conductive materials, and a packing density of the positive electrode mixture layer is 2.00 to 2.80 g/cc.

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Hyogo, Japan

Keisuke Minami