On-Board Cold Thermal Energy Storage System for Hydrogen Fueling Process

Abstract

The hydrogen storage pressure in fuel cell vehicles has been increased from 35 MPa to 70 MPa in order to accommodate longer driving range. On the downside, such pressure increase results in significant temperature rise inside the hydrogen tank during fast filling at a fueling station, which may pose safety issues. Installation of a chiller often mitigates this concern because it cools the hydrogen gas before its deposition into the tank. To address both the energy efficiency improvement and safety concerns, this paper proposed an on-board cold thermal energy storage (CTES) system, cooled by expanded hydrogen. During the driving cycle, the proposed system uses an expander, instead of a pressure regulator, to generate additional power and cold hydrogen gas. Moreover, CTES is equipped with phase change materials (PCM) to recover the cold energy of the expanded hydrogen gas, which is later used in the next filling to cool the high-pressure hydrogen gas from the fueling station.