Method and structure for switching between two battery units for driving an electrically driven device

An electric apparatus comprising:

• an electrically driven device;
• a temperature monitor which monitors temperature of a first battery having a given capacity which supplies electric power to said electrically driven device;
• a switch, operatively coupled to said electrically driven device and to said temperature monitor, which switches the supply of electric power to an other electric power source to said electrically driven device different from the first battery in response to a temperature as monitored by said temperature monitor exceeding a predetermined temperature;
• a remaining capacity monitor which is coupled to said electrically driven device and which monitors the remaining capacity of the first battery;
• and
• wherein said switch further switches to the electric power supplied by the other electric power source in response to monitoring a remaining capacity in said first battery which is below a predetermined capacity.

A computing apparatus comprising:

• a main unit equipped to be able to receive electric power from a main battery and a sub-battery, both the main battery and the sub-battery each having a variable temperature and being a charge-discharge battery;
• a temperature monitor operatively coupled to said main unit which monitors the temperature of the sub-battery under discharge;
• a battery switch, housed within said main unit, which switches to the main battery from the sub-battery and which receives electric power supplied by the main battery when a temperature as monitored by said temperature monitor exceeds a predetermined temperature;
• a remaining capacity monitor which is coupled to the main unit and which monitors the remaining capacity of the sub-battery;
• and
• wherein said battery switch switches from the sub-battery to the main battery thereby receiving electric power supplied by the main battery if a remaining capacity as monitored by said remaining capacity monitor is below a predetermined capacity.

A computing apparatus, comprising:

• a first connector which provides connection to a first battery unit having a variable temperature;
• a second connector which provides connection to a second battery unit constructed as a different unit from the first battery unit;
• a discharge transfer circuit which couples said first and second connectors and which transfers discharge to the second battery unit provided on said second connector prior to termination of electric power supplied to a system by activating a protection function disposed to the first battery unit when receiving said discharge from the first battery unit provided on said first connector;
• and
• wherein said discharge transfer circuit detects the temperature and remaining capacity of a battery cell in the first battery unit provided on said first connector and, if predetermined conditions are met transfers to discharge from the second battery unit provided on said second connector.

A battery switching method for switching batteries attached to an electrically driven device, comprising the steps of:

• detecting a cell temperature of a battery unit having an operating temperature that is discharging electrical power to said electrically driven device having a plurality of battery units;
• comparing the detected cell temperature with a temperature predetermined based on the operating temperature of a battery protection facility;
• effecting a switchover to discharge from another battery unit based on the result of said comparison step;
• and
• detecting a remaining capacity of the battery unit that is discharging;
• wherein the switchover is further a function of said detected remaining capacity being less than a predetermined capacity which is based on the battery protection facility.

A program product comprising:

• a computer usable storage medium having computer readable program code embodied therein for causing a computer to which a plurality of battery units can be coupled, the computer readable program code in said program product implementing functions of:
• detecting cell temperature of one of the plurality of battery units that is discharging;
• presetting a reference temperature determined bused on a condition under which battery protection is activated and storing said reference temperature in a memory;
• comparing the detected cell temperature with the stored reference temperature;
• effecting a switchover to discharge from another coupled battery unit if the cell temperature exceeds the reference temperature;
• detecting remaining capacity of the battery unit that is discharging;
• presetting a reference capacity determined based on a condition under which battery protection is activated and storing said reference capacity in the memory;
• comparing the detected remaining capacity with the stored reference capacity;
• and
• effecting a switchover to discharge from another coupled battery unit if the remaining capacity is less than the reference capacity.