Output capacitor also should have enough ripple-current rating to absorb the output switching ripple current. The output capacitor RMS current ICOUT is given:
At a certain input/output voltage and switching frequency, the voltage ripple can be reduced by increasing the output filter LC.
The BQ2461x has an internal loop compensator. To get good loop stability, the resonant frequency of the output inductor and output capacitor should be designed between 12 kHz and 17 kHz. The preferred ceramic capacitor has a 25-V or higher rating, X7R or X5R for 4-cell application.