Rechargeable battery arrangement

A rechargeable battery arrangement in which total service capacity for discharge from full charging to a final discharge voltage varies according to discharge conditions for discharging charged electric charge, comprising:

• at least one battery cell;
• a first data storage means for storing a plurality of total service capacities for discharge at a plurality of values of discharge current, respectively in unique association with a specific one of the total service capacities for discharge at a specific one of the values of discharge current;
• a second data storage means for storing a plurality of integrated quantities of discharged electricity for discharge from full charging to a predetermined discharge voltage at the values of discharge current, respectively;
• a voltage detection means for detecting a present voltage of the battery cell;
• a current detection means for detecting a present value of discharge current;
• a judgement means for judging whether or not the present voltage obtained by the voltage detection means is substantially coincident with the predetermined discharge voltage of the second data storage means;
• and
• a calculation means which obtains, from data obtained by the first data storage means on the basis of the present value of discharge current detected by the current detection means, a total service capacity corresponding to or closest to the present value of discharge current in case the judgement means judges that the present voltage is substantially coincident with the predetermined discharge voltage;
• wherein the calculation means obtains from the second data storage means one of the integrated quantities of discharged electricity corresponding to the present value of discharge current so as to calculate, from the total service capacity and the one of the integrated quantities of discharged electricity, a residual capacity of electric charge for discharge.