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Small displacement two-stroke engines are widely used as affordable and low-maintenance propulsion systems for motorcycles, scooters, hand-held power tools and others. In recent years, considerable progress regarding emission reduction has been reached. Nevertheless, a further improvement of two-stroke engines is necessary to cover protection of health and environment. In addition, the shortage of fossil fuel resources and the anthropogenic climate change call for a sensual use of natural resources and therefore, the fuel consumption and engine efficiency needs to be improved. With the application of suitable analyses methods it is possible to find improving potential of the working processes of these engines. The thermodynamic loss analysis is a frequently applied method to examine the working process and is universally adaptable.

Lithium-ion (Li-ion) batteries have become a research focus in the field of electric and hybrid electric vehicles, due to key advantages such as high specific energy, high energy density and low self-discharge rate in comparison with other battery technologies. Nevertheless, key issues involving safety, performance, cost, charging time and durability restrict mass market adoption of electric vehicles. Cold-temperature operation of Li-ion batteries is currently a subject of major research efforts. The effects of low temperature reduce the available energy of the battery and increase its internal impedance. Moreover, Li-ion batteries experience serious degradation mechanisms at low temperatures, strongly affecting performance, which poses difficulties for cold-climate countries. In this work, a battery-in-the-loop experiment has been set up to estimate and analyze Li-ion battery cold start ranges at temperatures down to -40 °C.