In order to improve the temperature uniformity inside the battery, the effects of partially utilizing metal and nonmetal materials on the heat sink of an air-cooled Lithium-ion (Li-ion) battery module were studied. Aluminum and aluminum foam as heat conductors and ceramic, and ceramic foam as insulators were examined using two-dimensional transient numerical simulation. The effects of the length of utilizing each material to the total length of the battery pack from the inlet by assuming that the other part of the heat sink is aluminum were investigated. The results showed that using aluminum foam and ceramic as part of the heat sink decreases the temperature uniformity of the battery pack. However, using the ceramic foam at the inlet section of the heat sink improves the temperature uniformity of the battery significantly. Furthermore, partially inserting the aluminum foam inside the air flow channel from outlet was investigated, and significant enhancement on the temperature uniformity of the battery pack was found. Overall, higher temperature reduction and higher temperature uniformity were achieved inside the battery pack using the combination of both ceramic and aluminum foams.