A power supply system includes a rechargeable battery to deliver a supply current to a load and a circuit to limit a discharge current when the rechargeable battery is supplying power to the load. The power supply system may further include an integrator for integrating a discharge voltage representing the discharge current that exceeds a predetermined limit, a pulse-width-modulation (PWM) circuit for producing a control signal having a PWM duty cycle representing the discharge voltage, and a driver circuit for delivering the supply current to said load according to said control signal. In one embodiment, a digital register is used to set the battery discharging current limit, in another embodiment an analog circuit is used to set the battery discharging current limit, and in yet another embodiment or a combination of the digital register and analog circuit is used to set the battery discharging current limit.