Abstract: Based on an input/output request from a server, a volume formed of a plurality of disk apparatuses having a RAID configuration is accessed. A performance measuring unit periodically measures the performance of the plurality of disk apparatuses during apparatus operation, and a performance-measurement-value storage unit stores a performance measurement value obtained through measurement. When the performance is determined from the performance measurement value as having been deteriorated, a performance improving unit adds a disk apparatus to increase the size of the volume. Also, the performance improving unit sets a performance threshold for each of performance measurement values of a plurality of types and, when at least any one of the performance measurement values falls below a corresponding performance threshold, adds a disk apparatus.

Abstract: A battery pack arranged to make a judgment concerning a loss of functional status and to perform selectively charge-and-discharge control and forced discharge control according to the judgment. The battery pack includes a charge-and-discharge control device for charging and discharging a battery, a forced discharge control device for forcedly discharging each cell, a function detecting device for detecting a functional status of the battery pack, a judging device for making a judgment concerning a loss of functional status detected by the function detecting device, and a control device for selectively controlling the charge-and-discharge control device and the forced discharge control device according to the judgment concerning a loss of functional status made by the judging device.

Abstract: A battery pack, using a battery having one or more cells as a power source and for connecting power to an external host device, and including charging/discharging apparatus connected in series with the battery and for performing charging and discharging, current detecting apparatus for detecting charging and discharging current, voltage detecting apparatus for detecting voltage, temperature detecting means for detecting temperature, and a controller, whereby the controller is operated in such manner that it turns the state from at least one of charging state, discharging state, charging stop state, and discharging stop state to another state by controlling the charging/discharging apparatus based on the charging/discharging current, the voltage and the temperature as detected, and the state information is transmitted to the external host device when there is a request or at regular interval or when there is state transition, and state transition such as a charging/discharging state or a stop state of the batt

Abstract: The present invention provides a battery pack, using a battery 1 comprising one or more cells as a power source and for connecting power to an external host device, and it comprises charging/discharging means 2-4 connected in series to the battery 1 and for performing charging and discharging, current detecting means 6 and 7 for detecting charging and discharging current, voltage detecting means 5 for detecting voltage, temperature detecting means for detecting temperature, and control means 9, whereby the control means is operated in such manner that it turns the state from at least one of charging state, discharging state, charging stop state, and discharging stop state to another state by controlling the charging/discharging means 2-4 based on the charging/discharging current, the voltage and the temperature as detected, and said state information is transmitted to the external host device when there is a request or at regular interval or when there is state transition, and state transition such as a charg

Abstract: The present invention provides a battery pack, in which both specific information such as information for identifying the battery and information of battery status are stored. The battery pack has a rewritable storage device for storing the specific information of the battery and the information of battery status, and operation switching means for switching operation status of the battery to a testing mode or to a normal mode. It is designed in such manner that the specific information and the battery status information stored in the storage device are turned to rewritable in the testing mode, and that the specific information of the battery is turned to non-rewritable in the operation mode.