The accurate judgment of battery thermal runaway has an important impact on the suppression and emergency response of battery thermal runaway. Thermal runaway of 18650 batteries with different state of charge (SOC) and under different heating power conditions were carefully studied. It was found that both the SOC and the heating power conditions would affect the thermal runaway of 18650 lithium-ion battery. The temperature of the thermal runaway beginning decreased with the increase of SOC or the heating power. The general process of battery thermal runaway included five stages: temperature rise, voltage drop, safety valve burst, jet fire, and temperature drop. Among them, a sudden drop in voltage could be considered as the beginning of battery thermal runaway and was a key parameter for judging battery thermal runaway. A voltage drops of 0.1V and a temperature greater than 80 degrees Ccould be used as criteria for thermal runaway in 18650 batteries.

The utilization of wasted Poly(lactic acid) (PLA) as low-cost carbon sources in solid-phase denitrification is hindered by its low biodegradability, which can be attributed to its high molecular weight. This study presents a new approach by blending high-molecular-weight PLA with a small amount of L-lactide (PLA/LAx) to treat nitrate-contaminated wastewater. The addition of L-lactide enhanced the release of carbon from high-molecular-weight PLA. An impressive denitrification efficiency of 96.7% was achieved, accompanied by extremely low levels of accumulated NO- 2-N (0.1 mg/L) and NH+4-N (0.4 mg/L). The quantity of L-lactide used significantly impacted the bacterial community structure. A high abundance of the phyla Bacteroidota and Chloroflexi asso-ciated with polymer degradation was observed. The most dominant denitrifier was the genus unclassi-fied_f__Rhodocyclaceae belonged to the phylum Proteobacteria. This study demonstrates that blending PLA with just 5 wt% lactide can transform it into a highly effective solid-phase carbon source to eliminate nitrates.

Water mist with additives is a promising emergency control technology for the lithium-ion battery's thermal runaway. Developing efficient, green, and environmental-friendly additive is a key issue to the technology. Here, using 18,650 batteries as the experimental object, three different suppression mechanism additives, i.e. sodium dodecyl benzene sulfonate (SDBS), sodium chloride (NaCl), and soy protein, were studied and discussed after optimizing the condition of water mist generated with different Here, using 18,650 batteries as the experimental object, three different suppression mechanism additives, i.e. sodium dodecyl benzene sulfonate (SDBS), sodium chloride (NaCl), and soy protein, were studied and discussed after optimizing the condition of water mist generated with different compressed air. The battery thermal runaway process concluded four stages, and the initial stage of explosion, i.e. the safety valve broke through companying with some noise and gases spilling out, was a typical phenomenon that suggested the beginning of thermal runaway. The water mist generated with optimized air pressure of 0.2 to 0.25 MPa, the droplet SMD size was 71-89 & mu;m, could effectively suppress the battery thermal runaway, decrease T2 quickly from about 700 & DEG;C to no more than 413 & DEG;C, and reduce the cooling time from above 1000 s to no more than 203 s. Although the mechanism of the three additives was different, all of them could evidently enhance the suppression effect of water mist on the lithium-ion battery's thermal runaway. Especially, the addition of 1.5% soy protein to water mist could decrease greatly both the flame temperature and the battery's surface temperature, and shorten 63% cooling time comparing to the pure water mist. The results showed that soy protein was an efficient and environmental-friendly additive for water mist to inhibit the thermal runaway of lithium-ion battery and had good potential practical application value. The in-depth research and analysis of SDBS and NaCl would provide basis data for the development of compound additive.

In this paper, two kinds of micro-emulsified biodiesel containing 5.6% and10% water are prepared. The effects of micro-emulsified biodiesel on engine's power, combustion and emission characteristics are investigated in a DI diesel engine The results show that under the rated speed and full load operating conditions, the maximum pressure rise rate and peak heat release rate for micro-emulsified biodiesel increase dramatically, while the ignition delay is prolonged and the combustion duration becomes shorter. Compared to base diesel, the HC, CO and smoke emissions from the engine fueled with biodiesel decrease sharply, except for a 9% increased NOx at large loads. However, micro-biodiesel could significantly reduce the NOx and smoke emissions, except for the higher HC and CO emissions at low and medium loads. When fuelled with 10%MB, the NOx and smoke emissions are 9% and 90% lower than that of diesel, respectively. Results reported here suggest that the application of micro-emulsified biodiesel in diesel engines has a potential to improve combustion process and reduce NOx, PM emissions simultaneously.

The micro-emulsion fuels were prepared with complex surfactant, and the effects of temperature on the stability of these fuels were investigated. The engine performance and the emissions were studied when the engine was fueled with diesel and micro-emulsion diesel respectively. Results showed that when the engine was fueled with micro-emulsion diesel, the NOXand smoke emissions were decreased obviously and HC and CO emissions were increased slightly. Discounting of surfactant and water, the specific fuel consumption of micro-emulsion diesel was lower than those of diesel under any load at the speed of 2900r/min.