System for measuring state of charge of storage battery

A system for measuring the state of charge of a storage battery comprising:

• an electrical quantity detecting section for detecting the quantity of electricity charged to said storage battery and the quantity of electricity discharged therefrom, and outputting said detected electrical quantities as digital signals;
• a temperature detecting section for detecting a temperature of said storage battery and outputting said detected temperature as a digital signal;
• a capacity measuring section for discharging electricity from said storage battery to a reference load connected to said storage battery to measure a capacity of said storage battery;
• a memory means including a first memory having at least data on the discharge capacity of said storage battery at said detected temperature with respect to the discharge capacity of said storage battery at a standard temperature stored therein, a second memory having data on the charging efficiency of said storage battery in relation to a charging rate of said storage battery and said detected temperature stored therein, and a third memory having operational equations stored therein which are necessary for calculating at said detected temperature at least one of an effective electrical quantity which said storage battery can discharge and an effective time for which said storage battery can discharge an effective quantity of electricity based on said detected electrical quantities and detected temperature of said storage battery;
• a digital-operation processing section for calculating at least one of said effective electrical quantity and effective time by digital-operation based on said output signals of said electrical quantity detecting section and temperature detecting section and said data and operational equations stored in said memory means;
• an indicating section for indicating at least one of said effective electrical quantity and said effective time;
• said digital-operation processing section acting to calculate said discharge capacity of said storage battery at said standard temperature based on said capacity of said storage battery measured by said capacity measuring section, said signal output by said temperature detecting section and said data stored in said memory means, and to allow said memory means to store said discharge capacity so calculated therein thereby correcting the variation in capacity of said storage battery due to the life variation thereof.

A system for measuring the state of charge of a storage battery comprising:

• an electrical quantity detecting section for detecting the quantity of electricity charged to said storage battery and the quantity of electricity discharged therefrom, and outputting said detected electrical quantities as digital signals;
• a temperature detecting section for detecting a temperature of said storage battery and outputting said detected temperature as a digital signal;
• a time detecting section for integrating a shelf time for which said storage battery is connected to neither a load nor a charger and converting said integrated time into a digital signal;
• a memory means including a first memory having at least data on the discharge capacity of said storage battery at said detected temperature with respect to the discharge capacity of said storage battery at a standard temperature stored therein, a second memory having data on the charging efficiency of said storage battery in relation to a charging rate of said storage battery and said detected temperature stored therein, and a third memory having operational equations stored therein which are necessary for calculating at said detected temperature at least one of an effective electrical quantity which said storage battery can discharge and an effective time for which said storage battery can discharge an effective quantity of electricity based on said detected electrical quantities and detected temperature of said storage battery and having operational equations stored therein which are necessary for calculating an electrical quantity of said storage battery lost due to the self-discharge thereof during said shelf time to correct said effective electrical quantity and said effective time;
• a digital-operation processing section for obtaining the correction in variation of discharge capacity of said storage battery due to said self-discharge based on said output signals of said electrical quantity detecting section and temperature detecting section, said signal output by said time detecting section, and said data and operational equations stored in said memory means to calculate at least one of said effective electrical quantity and said effective time by digital-operation;
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• an indicating section for indicating at least one of said effective electrical quantity and said effective time.

A system for measuring the state of charge of a storage battery comprising:

• an electrical quantity detecting section for detecting the quantity of electricity charged to said storage battery and the quantity of electricity discharged therefrom, and outputting said detected electrical quantities as digital signals;
• a temperature detecting section for detecting the temperature of said storage battery and outputting said detected temperature as a digital signal;
• a capacity measuring section for discharging electricity from said storage battery to a reference load connected to said storage battery to measure the capacity of said storage battery;
• a time detecting section for integrating a shelf time for which said storage battery is connected to neither a load nor a charger and converting said integrated time into a digital signal;
• a memory means including a first memory having at least data on the discharge capacity of said storage battery at said detected temperature with respect to the discharge capacity of said storage battery at a standard temperature stored therein, a second memory having data on the charging efficiency of said storage battery in relation to a charging rate of said storage battery and said detected temperature stored therein, and a third memory having operational equations stored therein which are necessary for calculating at said detected temperature at least one of a useful electrical quantity which said storage battery can discharge and a useful time for which said storage battery can discharge a useful quantity of electricity and having operational equations stored therein which are necessary for calculating an electrical quantity of said storage battery lost due to the self-discharge thereof during said shelf time to correct said useful electrical quantity and said useful time;
• a digital-operation processing section for obtaining the correction in variation of discharge capacity of said storage battery due to said self-discharge based on said output signals of said electrical quantity detecting section and said temperature detecting section, said capacity of said storage battery measured by said capacity measuring section, said signal output by said time detecting section, and said data and operational equations stored by said memory means to calculate at least one of said useful electrical quantity and said useful time by digital-operation;
• an indicating section for indicating at least one of said useful electrical quantity and said useful time;
• said digital-operation processing section acting to calculate said discharge capacity of said storage battery at said standard temperature based on said capacity of said storage battery measured by said capacity measuring section, said temperature detected by said temperature detecting section and said data stored by said memory means, and to allow said memory means to store said calculated discharged capacity therein, thereby correcting the variation of discharge capacity of said storage battery due to the life variation thereof.