Phase Change Matters

U.S. patent application 20180090728 (applicant LG Chem Ltd., Seoul, South Korea):

"A battery pack according to the present invention comprises a battery cell and a battery case accommodating the battery cell, wherein the battery case comprises an inner case accommodating the battery cell, an outer case disposed outside the inner case, and a cooling member between the inner and outer cases to indirectly cool the battery cell by using cool air generated by cooling the inner and outer cases."

http://www.freepatentsonline.com/20180090728.pdf