Most folks think that the Campagnolo EPS Power Unit is simply a battery that powers the EPS (Electronic Power System) components. It ios far more than just a battery. Inside the black Power Unit box, you will find a Lithium Ion battery as well as the DTI (Digital Tech Intelligence) unit which acts as the CPU or brains of the entire operation. Signals are sent from the shifters directly to the DTI. The DTI parses these signals and sends commands to the derailleurs. This all happens in a nanosecond with zero lag time.
The battery and DTI unit are encased in thermo plastic housing that is waterproof and fire resistant. Internal dampeners are added to stabilize the unit for accurate information processing. Depending on how much you ride, charge times last about 1000 miles or so from a full charge.