Abstract: Occurrence of an accident during access to an accessed portion is prevented. A control method for a work machine that uses an electric motor to be supplied with electric power from a battery unit as a drive source includes: allowing access to a predetermined accessed portion by releasing a lock mechanism; and rendering the electric motor in a non-drivable state while the lock mechanism is in a released state.

Abstract: Provided is a work machine control method, a work machine control program, a work machine control system, and a work machine that allow an operator to easily grasp the state of a secondary battery. The work machine control method includes executing relevant control regarding at least one of charging and discharging of the secondary battery of the work machine in accordance with a temperature of the secondary battery; and displaying relevant control information (first information G41 and second information Im3) on the relevant control.

Abstract: A hydraulic shovel to serve as this electric work machine comprises: an electric motor; a drive switch which detects an instruction to start up or stop the electric motor; a notification unit which provides notification about starting up the electric motor; a determination unit which, on the basis of an operating condition of the hydraulic shovel, determines whether or not the electric motor can be started up; and a notification control unit which controls the notification unit on the basis of a result of the determination by the determination unit. When the drive switch has detected an instruction to start up the electric motor, if the determination unit has determined that the electric motor can be started up, the notification control unit causes the notification unit to provide notification.

Abstract: Provided is a hydraulic shovel as an electric work machine, the hydraulic shovel comprising: a charger that supplies electric power from an external power source to a battery to charge the battery; an electric motor that is driven with electric power supplied from the battery; a hydraulic system including a hydraulic pump driven by the electric motor and a hydraulic actuator to which pressure oil is supplied by the hydraulic pump; a control unit that manages a physical quantity indicating the operation status of the electric motor as first operation information, and manages a physical quantity indicating the operation status of the battery including charging and discharging as second operation information; and an output unit that outputs the first operation information and the second operation information.

Abstract: A control device includes a power storage unit, a balance processing unit, and a control unit. The power storage unit includes a plurality of battery cells, and supplies power to a load. In a case where the load stops, the balance processing unit can execute balance processing of reducing variation in the voltage of each of the plurality of battery cells according to the degree of the variation in the voltage. The control unit generates, for display, a state image indicating the state of the variation according to the degree of the variation.

Abstract: This hydraulic shovel used as an electric work machine comprises: an electric motor, an inverter, a hydraulic actuator, a hydraulic pump, a direction switching valve, a pilot pump, a remote control valve, an electromagnetic valve, an accumulator, and a control unit. The accumulator is positioned in an oil path that branches from an oil path for pilot oil extending from the pilot pump to the electromagnetic valve, and accumulates the pilot pressure generated by the pilot pump. The control unit controls the inverter to stop the rotation of the electric motor after an interruption due to a depowered state of the electromagnetic valve.