Electrode, secondary battery, battery pack, electric vehicle, electric power storage system, electric power tool, and electronic apparatus

A secondary battery comprising:

• a cathode;
• an anode;
• and
• a non-aqueous electrolytic solution,
• the cathode including
• a cathode current collector, and
• a cathode active material layer provided on the cathode current collector, and
• the cathode active material layer being configured of a single layer and including a plurality of cathode active material particles, wherein
• distribution of average particle size of the cathode active material particles in a thickness direction of the cathode active material layer has gradient that allows the average particle size of the cathode active material particles to decrease gradually in a direction away from the cathode current collector.

An electrode comprising:

• a current collector;
• and
• an active material layer provided on the current collector,
• the active material layer being configured of a single layer and including a plurality of active material particles, wherein,
• when the cathode active material layer is divided, at one or more arbitrary positions, into two or more layers, an average particle size of the cathode active material particles in an uppermost layer is smaller than an average particle size of the cathode active material particles in a lowermost layer in the two or more layers of the divided cathode active material layer.

A battery pack comprising:

• a secondary battery;
• a control section configured to control operation of the secondary battery;
• and
• a switch section configured to switch the operation of the secondary battery according to an instruction of the control section,
• the secondary battery including
• a cathode,
• an anode, and
• a non-aqueous electrolytic solution,
• the cathode including
• a cathode current collector, and
• a cathode active material layer provided on the cathode current collector, and
• the cathode active material layer being configured of a single layer and including a plurality of cathode active material particles, wherein,
• when the cathode active material layer is divided, at one or more arbitrary positions, into two or more layers, an average particle size of the cathode active material particles in an uppermost layer is smaller than an average particle size of the cathode active material particles in a lowermost layer in the two or more layers of the divided cathode active material layer.

An electric vehicle comprising:

• a secondary battery;
• a conversion section configured to convert electric power supplied from the secondary battery into drive power;
• a drive section configured to operate according to the drive power;
• and
• a control section configured to control operation of the secondary battery,
• the secondary battery including
• a cathode,
• an anode, and
• a non-aqueous electrolytic solution,
• the cathode including
• a cathode current collector, and
• a cathode active material layer provided on the cathode current collector, and
• the cathode active material layer being configured of a single layer and including a plurality of cathode active material particles, wherein,
• when the cathode active material layer is divided, at one or more arbitrary positions, into two or more layers, an average particle size of the cathode active material particles in an uppermost layer is smaller than an average particle size of the cathode active material particles in a lowermost layer in the two or more layers of the divided cathode active material layer.

An electric power storage system comprising:

• a secondary battery;
• one or more electric devices configured to be supplied with electric power from the secondary battery;
• and
• a control section configured to control supplying of the electric power from the secondary battery to the one or more electric devices,
• the secondary battery including
• a cathode,
• an anode, and
• a non-aqueous electrolytic solution,
• the cathode including
• a cathode current collector, and
• a cathode active material layer provided on the cathode current collector, and
• the cathode active material layer being configured of a single layer and including a plurality of cathode active material particles, wherein,
• when the cathode active material layer is divided, at one or more arbitrary positions, into two or more layers, an average particle size of the cathode active material particles in an uppermost layer is smaller than an average particle size of the cathode active material particles in a lowermost layer in the two or more layers of the divided cathode active material layer.

An electric power tool comprising:

• a secondary battery;
• and
• a movable section configured to be supplied with electric power from the secondary battery,
• the secondary battery including
• a cathode,
• an anode, and
• a non-aqueous electrolytic solution,
• the cathode including
• a cathode current collector, and
• a cathode active material layer provided on the cathode current collector, and
• the cathode active material layer being configured of a single layer and including a plurality of cathode active material particles, wherein,
• when the cathode active material layer is divided, at one or more arbitrary positions, into two or more layers, an average particle size of the cathode active material particles in an uppermost layer is smaller than an average particle size of the cathode active material particles in a lowermost layer in the two or more layers of the divided cathode active material layer.

An electronic apparatus comprising

• a secondary battery as an electric power supply source,
• the secondary battery including
• a cathode,
• an anode, and
• a non-aqueous electrolytic solution,
• the cathode including
• a cathode current collector, and
• a cathode active material layer provided on the cathode current collector, and
• the cathode active material layer being configured of a single layer and including a plurality of cathode active material particles, wherein,
• when the cathode active material layer is divided, at one or more arbitrary positions, into two or more layers, an average particle size of the cathode active material particles in an uppermost layer is smaller than an average particle size of the cathode active material particles in a lowermost layer in the two or more layers of the divided cathode active material layer.