Patent ID: 8482254

Claim:
A remaining capacity measurement method of a battery C in a battery pack including a battery, a battery management system, a charging-discharging transistor, and a resistor, said remaining capacity measurement method, comprising the steps of: (a) establishing a first table of Full Charge Capacity (FCC) versus full charged constant current internal resistance DCIR of a reference battery A; (b) establishing a second table of DOD (Depth of Discharge) versus full charged constant current internal resistance DCIR of a reference battery B; (c) charging said battery C fully; (d) measuring constant current internal resistance DCIR of said fully charged battery C; (e) obtaining the FCC of said fully charged battery by looking up said first table according to said constant current internal resistance DCIR of said fully charged battery C; (f) obtaining the corresponding set of data in said second table according to constant current DCIR value of said fully charged battery C; (g) discharging said battery C; (h) measuring the constant current internal resistance DCIR of said battery C; (i) obtaining the DOD of said battery according to constant current internal resistance DCIR of said battery C by looking up said corresponding set of data in said second table; and (j) obtaining the remaining capacity of said battery C by the value FCC multiplied by the value (1-DOD).