This paper presents the effect of adding indium, a low melting metal on thermal energy storage performance of pentaerythritol in IC engine exhaust gas heat recovery application. Charging and discharging experiments were conducted using pentaerythritol added with 0.1, 0.5 and 1.0 wt. % of indium in a shell and tube heat recovery heat exchanger. The experimental results showed reduction in charging and discharging time due to the addition of indium leading to improved thermal energy storage performance of pentaerythritol. The charging efficiency of PE enhanced by 3.5, 6.8 and, 11.2% corresponding to 0.1, 0.5 and, 1.0 wt.% of indium under full load condition. The energy stored by pentaerythritol increased by 6.9, 14.65 and, 25.8% with respect to 0.1, 0.5 and 1.0 wt. % of indium. The energy recovered during the discharge period found increased by 5.4, 12.3 and, 18.6% corresponding to 0.1, 0.5 and, 1.0 wt. % of indium.