Devices with battery remaining capacity estimating functions

Abstract

A device includes an interface and a processor. The interface receives information for a parameter indicative of a status of a battery. The processor calculates a remaining capacity of the battery, calculates a capacity ratio of the calculated remaining capacity to a capacity reference of the battery, compares the parameter with a parameter reference to generate a first comparison result, compares the capacity ratio with a ratio reference to generate a second comparison result, sets an amount according to the first and second comparison results, and changes the calculated remaining capacity by the amount.

What is claimed is: 
     
         1 . A device comprising:
 an interface configured to receive information for a parameter indicative of a status of a battery; and   a processor, coupled to said interface, configured to calculate a remaining capacity of said battery and calculate a capacity ratio of the calculated remaining capacity to a capacity reference of said battery, configured to compare said parameter with a parameter reference to generate a first comparison result, configured to compare said capacity ratio with a ratio reference to generate a second comparison result, configured to set an amount according to said first and second comparison results, and configured to change said calculated remaining capacity by said amount.   
     
     
         2 . The device as claimed in  claim 1 , wherein said calculated remaining capacity is obtained by multiplying a current of said battery by a time period of operation of said battery. 
     
     
         3 . The device as claimed in  claim 1 , wherein said battery has a fully-charged capacity when said battery is fully-charged, and wherein said capacity reference comprises said fully-charged capacity. 
     
     
         4 . The device as claimed in  claim 1 , wherein said parameter comprises a charging current of said battery, and wherein said charging current decreases as said battery is charged in a predetermined charging mode. 
     
     
         5 . The device as claimed in  claim 4 , wherein said processor compares said charging current with a current reference to generate said first comparison result, and wherein said processor increases said calculated remaining capacity by said amount if said charging current is less than said current reference and if said capacity ratio is less than said ratio reference. 
     
     
         6 . The device as claimed in  claim 4 , wherein said processor compares said charging current with a first current reference and a second current reference to determine a range of said charging current, and wherein said processor increases said ratio reference if said first and second current references are decreased. 
     
     
         7 . The device as claimed in  claim 1 , wherein said parameter comprises a battery voltage of said battery in a discharging state. 
     
     
         8 . The device as claimed in  claim 7 , wherein said processor compares said battery voltage with a voltage reference to generate said first comparison result, and wherein said processor decreases said calculated remaining capacity by said amount if said battery voltage is less than said voltage reference and if said capacity ratio is greater than said ratio reference. 
     
     
         9 . The device as claimed in  claim 7 , wherein said processor compares said battery voltage with a first voltage reference and a second voltage reference to determine a range of said battery voltage, and wherein said processor decreases said ratio reference if said first and second voltage references are decreased. 
     
     
         10 . A method for estimating a remaining capacity of a battery, said method comprising:
 calculating, using a processor, a capacity ratio of a calculated remaining capacity of said battery to a capacity reference of said battery;   comparing a parameter indicative of a status of said battery with a parameter reference to generate a first comparison result;   comparing said capacity ratio with a ratio reference to generate a second comparison result;   setting an amount according to said first and second comparison results; and   changing said calculated remaining capacity by said amount.   
     
     
         11 . The method as claimed in  claim 10 , further comprising:
 multiplying a current of said battery by a time period of operation of said battery to obtain said calculated remaining capacity.   
     
     
         12 . The method as claimed in  claim 10 , further comprising:
 comparing a charging current of said battery with a current reference to generate said first comparison result; and   increasing said calculated remaining capacity by said amount if said charging current is less than said current reference and said capacity ratio is less than said ratio reference.   
     
     
         13 . The method as claimed in  claim 10 , further comprising:
 comparing a battery voltage of said battery with a voltage reference to generate said first comparison result; and   decreasing said calculated remaining capacity by said amount if said battery voltage is less than said voltage reference and said capacity ratio is greater than said ratio reference.   
     
     
         14 . A device comprising:
 a processor; and   a memory coupled to said processor, said memory comprising computer-readable instructions that, when executed by said processor, cause said processor to calculate a remaining capacity of said battery, to calculate a capacity ratio of the calculated remaining capacity to a capacity reference of said battery, to compare a parameter indicative of a status of said battery with a parameter reference to generate a first comparison result, to compare said capacity ratio with a ratio reference to generate a second comparison result, to set an amount according to said first and second comparison results, and to change said calculated remaining capacity by said amount.   
     
     
         15 . The device as claimed in  claim 14 , wherein said computer-readable instructions, when executed by said processor, cause said processor to multiply a current of said battery by a time period of operation of said battery to obtain said calculated remaining capacity. 
     
     
         16 . The device as claimed in  claim 14 , wherein said battery has a fully-charged capacity when said battery is fully charged, and wherein said capacity reference comprises said fully-charged capacity. 
     
     
         17 . The device as claimed in  claim 14 , wherein said parameter comprises a charging current of said battery, and wherein said computer-readable instructions, when executed by said processor, cause said processor to compare said charging current with a current reference to generate said first comparison result, and to increase said calculated remaining capacity by said amount if said charging current is less than said current reference and if said capacity ratio is less than said ratio reference. 
     
     
         18 . The device as claimed in  claim 14 , wherein said parameter comprises a charging current of said battery, and wherein said computer-readable instructions, when executed by said processor, cause said processor to compare said charging current with a first current reference and a second current reference to determine a range of said charging current, and to increase said ratio reference if said first and second current references are decreased. 
     
     
         19 . The device as claimed in  claim 14 , wherein said parameter comprises a battery voltage of said battery, and wherein said computer-readable instructions, when executed by said processor, cause said processor to compare said battery voltage with a voltage reference to generate said first comparison result, and to decrease said calculated remaining capacity by said amount if said battery voltage is less than said voltage reference and if said capacity ratio is greater than said ratio reference. 
     
     
         20 . The device as claimed in  claim 14 , wherein said parameter comprises a battery voltage of said battery, and wherein said computer-readable instructions, when executed by said processor, cause said processor to compare said battery voltage with a first voltage reference and a second voltage reference to determine a range of said battery voltage, and to decrease said ratio reference if said first and second voltage references are decreased.