Cold plate designs for lithium ion battery stack of an electric vehicle.

摘要

The demands for electric battery storage are increasing for greater use in electric vehicles and for greater energy storage needs for alternative energy sources and electric grid systems. The automobile industries account for a significant percent of the total fuel consumption in the US. The necessity for reducing fuel consumption and emissions led to the development of the electric vehicles including hybrid electric and plug-in electric, which uses a drive system consisting of electric battery storage, electric motors and regenerative braking system.;Previous experimental and simulation studies at NIU indicate that at higher discharge and charge rates the battery performance decreases due to increased polarization losses, which results in increased internal heat generation and temperature raise of the lithium-ion battery. Temperature variation greatly affects the performance and capacity of the battery. Beyond certain temperature level thermal runaway will occur and thus increases temperature uncontrollably, causing serious safety problems. Thermal run-away is even more critical for automobile applications which involve very high discharge and charge rates during driving and fast charging conditions. An enhanced battery cooling scheme is required to achieve optimum battery performance. The objective of this study is to develop cold plate designs for thermal heat management of Li-ion battery stack of an electric vehicle for enhanced performance subjected to electric vehicle discharge rates associated with the driving conditions and high rates for fast charging of the battery. A computer simulation model based on coupling a battery model that takes into account of the electrochemical kinetics and heat generation with a CFD model for conjugate heat transfer and flow dynamics will be used to investigate the electrochemical and thermal behavior of the battery under a variety of load conditions associated with vehicle load cycles. A number of different cold plate designs have been analyzed to meet the thermal management requirements of the battery stack for enhanced battery performance required in an electric vehicle.