Switching-based charger with continuously built-in resistor detector (CBIRD) and analog multiplication-division unit (AMDU) for fast charging in Li-Ion battery

Proposed continuously built-in resistor detector (CBIRD) monitors the built-in resistance (BIR) of the Li-Ion batteries for achieving fast charging process. Owing to the detection of the battery built-in resistance in real-time, the transition from the constant-current (CC) mode to the constant-voltage (CV) mode can be postponed to have large energy storing in the battery, Thus, the charging time of the switching-based charger can be effectively reduced. The CBIRD is composed of four analog circuits, which are the differentiator, the subtraction sample-and-hole (S/H), analog multiplication-division unit (AMDU), and voltage adder for accurate BIR detection. Thus, the proposed switching-based charger with the CBIRD has 45% charging time improvement for Li-ion batteries.