Toyota Jidosha Kabushiki Kaisha

Panasonic Holdings Corporation

Hiroki Iguchi

Hideki Sano

Kaoru Inoue

Akihiro Taniguchi

Hideaki Fujita

Kouhei Tsuzuki

Akira Tsujiko

Manufacturing a lithium-ion battery includes assembling the lithium-ion battery; and performing an initial charging on the lithium-ion battery. The lithium-ion battery includes a positive electrode, a negative electrode, and an electrolyte; the negative electrode contains a negative electrode active material containing a precursor of a silicon material, the precursor having a composition represented by SiOwhere a relationship of 0<x<2 is satisfied. The initial charging includes a first step where the charging is performed to an intermediate voltage at a first current rate, and a second step where the charging is performed from the intermediate voltage to a maximum voltage at a second current rate. The first current rate is lower than 0.5 C; the second current rate is higher than the first current rate; and the intermediate voltage is 3.75 V or higher.

Lithium-ion battery and method of manufacturing the same

A secondary battery module includes a nonaqueous-electrolyte secondary battery and an elastic body, wherein a negative electrode constituting the nonaqueous-electrolyte secondary battery includes a negative-electrode active material layer, the negative-electrode active material layer includes a first layer, and a second layer that is formed on the first layer and has a higher compression modulus than the first layer, a separator constituting the nonaqueous-electrolyte secondary battery has a lower compression modulus than the first layer, the elastic body has a lower compression modulus than the separator, the graphite particles contained in the first layer have a BET specific surface area of 1 to 2.5 m/g, and the content of Si particles in the first layer is 6 mass % to 13 mass % relative to the total amount of the negative-electrode active material layer.

Nonaqueous-electrolyte secondary battery and secondary battery module

A secondary battery module according to the present embodiment includes a nonaqueous-electrolyte secondary battery and an elastic body, wherein a negative electrode constituting the nonaqueous-electrolyte secondary battery includes a negative-electrode current collector and a negative-electrode active material layer, the negative-electrode active material layer includes a first layer formed on the negative-electrode current collector, and a second layer that is formed on the first layer and has a higher compression modulus than the first layer, a separator constituting the nonaqueous-electrolyte secondary battery has a lower compression modulus than the first layer, the elastic body has a lower compression modulus than the separator, a graphite particles contained in the first layer have a BET specific surface area of 1 to 2.5 m/g, and the first layercontains 0.01 mass % to 0.4 mass % of a carbon nanotube having one to five graphene sheets.

A negative electrode active material includes graphite and silicon oxide. On a rectangular coordinate system having an SOC of the battery on a horizontal axis and a dimension of the battery on a vertical axis, a charging profile of the battery includes a first stage and a second stage. When the battery is charged at a current rate equal to or higher than an inherent current rate, a first slope is less steep than a second slope. When the battery is charged at a current rate lower than the inherent current rate, the first slope is steeper than the second slope. During the initial charging, at least charging in the first stage is performed at a current rate lower than the inherent current rate. After the initial charging proceeds to the second stage, the thermal aging is performed at an SOC included in the second stage.

Method of producing lithium-ion battery

An electrolyte solution for a lithium-ion battery is provided. The electrolyte solution contains at least a solvent and a lithium salt. The lithium salt is dissolved in the solvent. The solvent contains acetic anhydride at a concentration not lower than 80 vol %.

Electrolyte solution and lithium-ion battery

An electrolyte solution for a lithium-ion battery is provided. The electrolyte solution contains at least a solvent and a lithium salt. The solvent contains at least methoxyacetone.

An electrolyte solution is used for a lithium ion battery. The electrolyte solution contains at least a solvent and lithium salt. The solvent contains at least methoxymethyl formate.

Electrolyte solution and lithium ion battery

A non-aqueous electrolyte secondary battery includes a housing, a stack-type electrode array accommodated in the housing, and an electrolyte solution. The electrolyte solution includes an infiltrated portion infiltrated into the stack-type electrode array and an excess portion other than the infiltrated portion. In a set-up state that the non-aqueous electrolyte secondary battery is arranged such that a direction of stack of the stack-type electrode array is orthogonal to a vertical direction, a lower end of the separator projects below lower ends of the positive electrode and the negative electrode. In the set-up state, within a range of an operating state of charge, a projecting portion of any of the plurality separators is always in contact with the excess portion and the plurality of positive electrodes and the plurality of negative electrodes are not in contact with the excess portion at any time.

Non-aqueous electrolyte secondary battery

A method of producing a lithium ion secondary battery includes preparing a case in which an electrode group including at least a positive electrode and a negative electrode is accommodated; impregnating a first electrolyte solution into the electrode group, lowering a potential of the negative electrode to a first potential, injecting FEC into a case, and lowering a potential of the negative electrode to a second potential. The negative electrode contains at least graphite and silicon oxide. The first electrolyte solution does not contain FEC. An additive has a reductive decomposition potential of 0.5 V (vs. Li/Li) or more and 1.5 V (vs. Li/Li) or less. The first potential is higher than 0.2 V (vs. Li/Li) and is equal to or lower than the reductive decomposition potential. The second potential is 0.2 V (vs. Li/Li) or less.

Method of producing lithium ion secondary battery

A method of manufacturing a non-aqueous electrolyte secondary battery includes: (A) constructing an electrode group including a positive electrode and a negative electrode; (B) impregnating the electrode group with a first electrolyte solution; (C) charging the electrode group impregnated with the first electrolyte solution to a voltage of 4.3 V or more; and (E) manufacturing the non-aqueous electrolyte secondary battery by impregnating the electrode group with a second electrolyte solution after the charging. The first electrolyte solution includes a first solvent, a first lithium salt, and biphenyl. The first solvent does not include 1,2-dimethoxyethane. The second electrolyte solution includes a second solvent and a second lithium salt. The second solvent includes 1,2-dimethoxyethane.

Method of manufacturing non-aqueous electrolyte secondary battery

A battery management system includes: measuring a surface pressure of a vehicle-mounted secondary battery (battery cell) for driving the vehicle with a lapse of time; calculating a high-rate driving frequency coefficient on the basis of the measured surface pressure at intervals of a predetermined period (24 hours); deriving a high-rate driving frequency on the basis of the number of times that the calculated high-rate driving frequency coefficient has exceeded a predetermined threshold; and selecting a replacement battery from among batteries including a high-power battery on the basis of the derived high-rate driving frequency.

Growing community of inventors

Nagoya, Japan

Hiroki Iguchi