Polymeric hollow fibers: A supercompact cooling of Li-ion cells

Abstract

An unconventional design of the heat exchanger has been introduced for conventional liquid cooled systems of battery modules/packs of electric vehicles (EVs). It is deemed unconventional, because only non-metallic materials are used, namely polydicyclopentadiene (PDCPD) as a mechanical housing and polymeric hollow fibers as coolant channels. The heat exchanger is lightweight, electrically non-conductive, durable, wear resistant, low cost, manufacturable. Very small in diameter (<1 mm), the fibers were woven in a specific manner around a number of cylindrical Li-ion cells 18650. After that, the fibers' position was fixed in PDCPD processed during the reaction injection molding (RIM). In this study, the cooling performance of the heat exchanger was examined both numerically and in experiments. The findings of both approaches concur with each other. From the perspective of temperature homogeneity, the current prototype shows acceptable performance when compared to the standard exchangers on the market. The results presented show further room for promising design modifications.