Effect analysis on the low-temperature preheating performance of a novel micro-combustor air preheater for the cold start of the Li-ion battery packs.

In this work, a micro-combustor (MC) air preheater as the heat source is developed. This novel air preheater has a compact size and outputs hot air with a wide range of temperatures with high temperature uniformity, which can well meet the preheating needs of Li-ion batteries in cold environments. Numerical studies are carried out to investigate the effects of baffle height, number of fins N fin , hot air inlet velocity, cold air inlet velocity and combustor inlet velocity on the performance of the air preheater. The heating power of the air preheater can be adjusted by changing combustor inlet velocity V combustor , the outlet temperature can be easily adjusted by changing cold air inlet velocity V cold and hot air inlet velocity V hot , and the addition of baffles makes the outlet temperature very uniform. The results show that the height of the baffle of 20 mm and 30 mm makes Δ T air not exceed 1.5 K. The air preheater performance is better with fin number 6, and the maximum air temperature of 309.8 K is obtained with fin number and V hot of 6 and 0.3 m/s respectively. T air can vary between 287.8 K and 309.8 K when V combustor = 12 m/s. • A micro-combustor air preheater for the cold start of Li-ion battery packs is developed. • Effects of different factors on the low-temperature preheating performance is investigated. • Optimized parameters of the micro-combustor air preheater are obtained. [ABSTRACT FROM AUTHOR]