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As compared with other batteries, lithium-ion batteries are featured by high power density, long service life, high energy density, environmental friendliness and thus have found wide application in the area of consumer electronics. However, lithium-ion batteries for electric and hybrid electric vehicles (EVs and HEVs) have high capacity and large serial-parallel numbers, which, coupled with such problems as safety, durability, cost and uniformity, imposes limitations on the wide application of lithium-ion batteries in the EVs and HEVs. The narrow area in which lithium-ion batteries operate with safety and reliability necessitates the effective control and through the use of management of battery management system. Battery state of health (SOH) monitoring has become a crucial challenge in EVs and HEVs research, as SOH significantly affects the overall vehicle performance and life cycle. This paper presents both cycling and calendar aging at high and low temperatures.

Many approaches have been taken to determine the burning velocity in internal combustion engines. Experimentally, the burning velocity has been determined in optically accessible gasoline engines by tracking the propagation of the flame front from the spark plug to the end of the combustion chamber. These experiments are costly as they require special imaging techniques and major modifications in the engine structure. Another approach to determine the burning velocity is from 3D CFD simulation models. These models require basic information about the mechanisms of combustion which are not available for distillate fuels in addition to many assumptions that have to be made to determine the burning velocity. Such models take long periods of computational time for execution and have to be calibrated and validated through experimentation.

Estimation of soot in real time would help in the development of engine controls during engine production to meet the emissions goals and for on-board diagnostics. This paper presents a new approach to the estimate the soot emissions from the ion current measured inside the cylinder during engine operation. The investigation was carried out on a 4.5L heavy duty, turbocharged diesel engine. The glow plug was modified to act as an ion current probe, in addition to its main function. Algorithms were developed for the ion current signal to estimate the soot formed on a cycle-by-cycle basis. A comparison was made between the estimated soot emissions and measurements made by using an opacity meter under steady state as well as under transient engine operating conditions. In this research, a non-linear multiple regression model (NLMR) was used to estimate soot percentage from the ion current signal.

This paper investigates the relationship between NOx and ion current measured inside the combustion chamber of a heavy duty diesel engine under different operating conditions. Nevertheless, ion current is a local signal, thus it is important to measure NOx concentrations at the same exact location of the ion current probe. A novel technique is developed to simultaneously sample in-cylinder NOx and measure the ion current signal by adapting gas sampling probes for ion sensing. The cycle-resolved traces for the rate of heat release, NO mole fraction and ion current were analyzed to determine the contribution of the premixed combustion and the mixing-diffusion controlled combustion on NO formation and ionization in diesel engines.

Internal combustion engine control requires feedback signals to the ECU in order to meet the increasingly stringent emissions standards. Reducing the number of on-board sensors needed for proper engine performance would reduce the cost and complexity of the electronic system. This paper presents a new technique to enable one engine element, the fuel injector, to perform multiple sensing tasks in addition to its primary task of delivering the fuel into the cylinder. The injector is instrumented within an electric circuit to produce a signal indicative of the ionization produced from the combustion process in electronically controlled diesel engines. The output of the multi sensing fuel injector (MSFI) system can be used as a feedback signal to the engine control unit (ECU) for injection timing and diagnostics of the injection and combustion processes.

This paper presents an experimental investigation conducted to determine the parameters that control the behavior of autoignition in a small-bore, single-cylinder, optically-accessible diesel engine. Depending on operating conditions, three types of autoignition are observed: a single ignition, a two-stage process where a low temperature heat release (LTHR) or cool flame precedes the main premixed combustion, and a two-stage process where the LTHR or cool flame is separated from the main heat release by an apparent negative temperature coefficient (NTC) region. Experiments were conducted using commercial grade low-sulfur diesel fuel with a common-rail injection system. An intensified CCD camera was used for ultraviolet imaging and spectroscopy of chemiluminescent autoignition reactions under various operating conditions including fuel injection pressures, engine temperatures and equivalence ratios.