Calorimeter

About: Calorimeter is a research topic. Over the lifetime, 5878 publications have been published within this topic receiving 77157 citations.

Thermal hazard evaluations of 18650 lithium-ion batteries by an adiabatic calorimeter

Abstract: In this study, the thermal hazard features of various lithium-ion batteries, such as LiCoO2 and LiFePO4, were assessed properly by calorimetric techniques. Vent sizing package 2 (VSP2), an adiabatic calorimeter, was used to measure the thermal hazards and runaway characteristics of the 18650 lithium-ion batteries under an adiabatic condition. The thermal behaviors of the lithium-ion batteries were obtained at normal and abnormal conditions in this study. The critical parameters for thermal hazardous behavior of lithium-ion batteries were obtained including the exothermic onset temperature (T 0), heat of decomposition (ΔH), maximum temperature (T max), maximum pressure (P max), self-heating rate (dT/dt), and pressure rise rate (dP/dt). Therefore, the result indicates the thermal runaway situation of the lithium-ion battery with different materials and voltages in view the of TNT-equivalent method by VSP2. The hazard gets greater with higher voltage. Without the consideration of other anti-pressure measurements, different voltages involving 3.3, 3.6, 3.7, and 4.2 V are evaluated to 0.11, 0.23, 0.88, and 1.77 g of TNT. Further estimation of thermal runaway reaction and decomposition reaction of lithium-ion battery can also be confirmed by VSP2. It shows that the battery of a fully charged state is more dangerous than that of a storage state. The technique results showed that VSP2 can be used to strictly evaluate thermal runaway reaction and thermal decomposition behaviors of lithium-ion batteries. The loss prevention and thermal hazard assessment are very important for development of electric vehicles as well as other appliances in the future. Therefore, our results could be applied to define important safety indices of lithium-ion batteries for safety concerns.

High-resolution thermal imaging with a combination of nano-focus X-ray diffraction and ultra-fast chip calorimetry.

Abstract: A microelectromechanical-systems-based calorimeter designed for use on a synchrotron nano-focused X-ray beamline is described This instrument allows quantitative DC and AC calorimetric measurements over a broad range of heating/cooling rates (≤100000 K s−1) and temperature modulation frequencies (≤1 kHz) The calorimeter was used for high-resolution thermal imaging of nanogram-sized samples subjected to X-ray-induced heating For a 46 ng indium particle, the measured temperature rise reaches ∼02 K, and is directly correlated to the X-ray absorption Thermal imaging can be useful for studies of heterogeneous materials exhibiting physical and/or chemical transformations Moreover, the technique can be extended to three-dimensional thermal nanotomography

The thermodynamics of the LaNi5-H2 system by differential heat flow calorimetry I: Techniques; the α + β two-phase region

Abstract: The use of a heat flow calorimeter with the differential twin cell configuration to study intermetallic compound-hydrogen reactions is described. The techniques of calibration and operation of both the gas titration system and the calorimeter, which are required to obtain high precision enthalpies, are described and discussed. Enthalpies for the reaction in the two-phase region of the LaNi5-H2 system are independent of the overall composition but exhibit a small hysteresis with ΔHabs = −32.30 ± 0.07 kJ (mol H2)−1ΔHdes = 31.83 ± 0.09 kJ (mol H2)−1 where ΔHabs is the enthalpy of absorption, ΔHdes is the enthalpy of desorption and the errors are the standard deviations. The value of ΔHdes is the best value for the enthalpy of reaction between equilibrium phases with a total probable error of ±0.5 kJ (mol H2)−1.