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Upcoming legislation towards zero carbon emission is pushing the electric vehicle as the main solution to achieve this goal. However, electric vehicles still require further battery development to meet customer’s requirements as fast charge and high energy density. Both demands come with the cost of higher heat dissipation as lithium transport and chemical reaction inside the battery need to be performed faster, increasing the joule effect inside the battery. Due to its working principle, which guarantees an adiabatic environment, an accelerating rate calorimeter is used to study thermal phenomena in batteries like a thermal runaway. However, this equipment is not prepared to work with optical access, which helps to study and to comprehend battery surface distribution and other thermal aspects. This paper aims to show a methodology to correct temperature measurement when using a thermographic camera and optical access of sapphire in an accelerating rate calorimeter.

Lithium-ion batteries have a well-documented failure tendency under abuse conditions with a significant release of gases and heat. This failure originated from the decomposition reactions within the battery’s electrochemical components, resulting in gas generation and increased internal pressure. To optimize battery safety, it is crucial to understand their behaviors when subjected to abuse conditions. The 18650 format cell incorporates a vent mechanism within a crimped cap to relieve pressure and mitigate the risk of rupture. However, cell venting introduces additional safety concerns associated with flammable gases and liquid electrolyte that flow into the environment. Experiments were performed with two venting caps with well-known geometries to quantify key parameters in describing the external dynamic flow of battery venting and to validate a CFD model.

Stringent emission legislations have pushed engine operation to borderline knock. Knocking combustion limits engine efficiency, putting a threshold in carbon emission reduction that impairs further decarbonization of the transport sector. In this way, online knock monitoring is very important during engine development and calibration to allow operation with higher efficiency levels. Commonly, knock detection methods require complex calculations with high computational cost. Furthermore, these methods normally need previous calibration of a threshold value for each specific engine to indicate the knock limit, requiring important engineering resources and time. Hence, this paper proposes a novel methodology for knock detection that is simple, does not require prior calibration and can be used for sensorless knock detection. The method is applied by relating the crank angle of maximum pressure rise rate (AMPRR) with the angle of 50% of fuel mass burned (CA50), the so-called G Index (GI).

The prediction of ignition delay times is very useful during the development phase of internal combustion engines. When it comes to biofuels such as ethanol and its blends with gasoline, its importance is enhanced, especially when it comes to flex-fuel engines and the need to address current and future emissions legislations and efficiency goals. The ignition delay time measured as the angular difference between the spark discharge time, as commanded by the ECU and a relevant fraction of fuel mass burned (usually, 2, 5 or 10%). Experimental tests were performed on a downsized state-of-the-art internal combustion engine. Engine speed of 2500 rpm, with load of 6 and 13 bar IMEP were set for investigation. Stoichiometric operation and MBT or knock-limited spark timings were used, while valve overlap was varied, in order to address the effects of scavenging and residuals on ignition delay times.

Global warming and pollutant emission concerns have been driving research towards cleaner and environmentally friendly fuels. Like ethanol, butanol is a promising biofuel with characteristics such as higher calorific value and lower latent heat of vaporization. Due to its similar properties to those of gasoline, butanol stands as a potential gasoline surrogate. Butanol can be produced from through the ABE (acetone–butanol–ethanol) fermentation process, which uses bacterial fermentation to produce acetone, n-Butanol, and ethanol from carbohydrates such as starch and glucose. This work presents the experimental results of a single-cylinder spark ignition research engine equipped with port fuel injection. Several compression ratios were compared via spacer rings. Fuels as n-butanol, hydrous ethanol (E95W05) and their blends were evaluated in comparison to primary reverence fuel (isooctane).

Hydrous ethanol is pointed out as one of the major alternative fuel for internal combustion engines, because it is environmental friendly (almost zero CO2 emission) and has excellent combustion properties. Recent studies have shown that ethanol-water fuel blends with higher water content (so-called wet ethanol) can reduce the overall costs of ethanol production. The use of wet ethanol results in lower nitrogen oxides emissions at the cost of reduced lower heating value per mass of fuel blend, which may result in less thermal efficiency. On the other hand, the increase in water content improves knock resistance. Thus, this study aims to investigate the effects of mechanical compression ratio variation on a spark ignition engine using ethanol-water fuel blends containing 4, 10, 20 and 30% v/v of water in ethanol. The research was carried out in a SI single cylinder engine, port fuel injected, 0.668 dm3 with the compression ratio modified by spacer rings.

Concerns about global warming, pollutant emissions and energy security have driven research towards cleaner and more environmentally friendly fuels. In the same way as ethanol, butanol is a promising biofuel but with different characteristics such as higher calorific value and lower latent heat of vaporization. It has similar properties to those of gasoline, which makes it a potential surrogate for this fossil fuel. Therefore, the present study proposes a comparison among four different fuels i.e. n-butanol, n-butanol and ethanol blend (B73E27), gasoline and ethanol blend (G73E27), and hydrous ethanol. A single cylinder naturally aspirated research engine with port fuel injection was employed. Engine performance was experimentally evaluated and combustion parameters were determined through reverse calculation based on acquired intake, exhaust and in-cylinder pressure on GT-Power.