•The effect of particle contact on heat storage tank performance was studied.•The evolutions of apparent thermal resistance were studied.•The evolutions of average heat flux were studied. Energy Internet can guarantee the efficient and stable use of renewable energy, and the energy storage device bears an important linking task. In order to achieve a fast response to Energy Internet, energy storage devices often use metal particle heat storage tanks. The contact between particles is complicated, which directly affects the heat storage performance of the particle tank. Therefore, it is very important to study the effects of the contact between the particles on the performance of the fast-response heat storage tank. In this paper, a 2D steady-state heat storage and release model of the elliptical particles tank was established. The influence of particle contact coefficient on the performance of the heat storage tank was studied. The results showed that with increases of the particle contact coefficient, the average heat flux increases, and the apparent thermal resistance decreases. The work performance and dynamic response performance of the heat storage tank increase. The effect of vacancy on the performance of the heat storage tank is basically not affected by the change of particle contact coefficient.