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Ever growing traffic has a detrimental effect on health and environment. In response to climate warming and health concerns, governments worldwide enforce more stringent emission standards. NOx emissions limits are some of the most challenging to meet using fuel-efficient lean-burn engines. The Selective Catalytic Reduction (SCR) is one consolidated NOx after-treatment technique using urea water solution (UWS) injection upstream of the catalytic converter. A recent development of SCR, using gaseous ammonia injection, reduces wall deposit formation and improves the cold-start efficiency. The mixing of gaseous ammonia with the exhaust gases is one of the key challenges that need to be overcome, as the effectiveness of the system is strongly dependent on the mixture uniformity at the inlet of the SCR catalyst.

Meeting Euro 6d NOx emission regulations lower than 80 mg/km for light duty diesel (60 mg/km gasoline) vehicles remains a challenge, especially during cold-start tests at which the selective catalyst reduction (SCR) system does not work because of low exhaust gas temperatures (light-off temperature around 200 °C). While several exhaust aftertreatment system (EATS) designs are suggested in literature, solutions with gaseous ammonia injections seem to be an efficient and cost-effective way to enhance the NOx abatement at low temperature. Compared to standard SCR systems using urea water solution (UWS) injection, gaseous NH3 systems allow an earlier injection, prevent deposit formation and increase the NH3 content density. However non-uniform ammonia mixture distribution upstream of the SCR catalyst remains an issue. These exhaust gas/ NH3 inhomogeneities lead to a non-optimal NOx reduction performance, resulting in higher than expected NOx emissions and/or ammonia slip.

One of the solutions for reducing greenhouse gas emissions in the transport sector is the electrification of mobility. The technology currently most widely used by car manufacturers is the Li-ion battery (LiB). Unfortunately, Li-ion batteries can suffer dramatic events with catastrophic consequences known as thermal runaway (TR). TR has many possible causes: excessive temperature, mechanical deformation, electrical overcharge, internal short circuit. Typically, TR causes violent combustion that is difficult or impossible to control, with the emission of potentially toxic gases and particles. TR is a major problem for manufacturers and can have serious consequences for users. Understanding TR is a key safety issue. This paper presents a new methodology to characterize the thermal runaway of Li-ion battery cells, combining gas analysis, thermodynamic measurements and high-speed imaging.