Thermal runaway caused fire and explosion of lithium ion battery

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are (small) systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. [J. Appl. Phys. 81, 6692 (1997)], was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

A Benchmark Study on the Thermal Conductivity of Nanofluids

A review of lithium ion battery failure mechanisms and fire prevention strategies

Power train electrification is promoted as a potential alternative to reduce carbon intensity of transportation. Lithium-ion batteries are found to be suitable for hybrid electric vehicles (HEVs) and pure electric vehicles (EVs), and temperature control on lithium batteries is vital for long-term performance and durability. Unfortunately, battery thermal management (BTM) has not been paid close attention partly due to poor understanding of battery thermal behaviour. Cell performance change dramatically with temperature, but it improves with temperature if a suitable operating temperature window is sustained. This paper provides a review on two aspects that are battery thermal model development and thermal management strategies. Thermal effects of lithium-ion batteries in terms of thermal runaway and response under cold temperatures will be studied, and heat generation methods are discussed with aim of performing accurate battery thermal analysis. In addition, current BTM strategies utilised by automotive suppliers will be reviewed to identify the imposing challenges and critical gaps between research and practice. Optimising existing BTMs and exploring new technologies to mitigate battery thermal impacts are required, and efforts in prioritising BTM should be made to improve the temperature uniformity across the battery pack, prolong battery lifespan, and enhance the safety of large packs.

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A critical review of thermal management models and solutions of lithium-ion batteries for the development of pure electric vehicles

Review on battery thermal management system for electric vehicles

Reciprocating air flow for Li-ion battery thermal management to improve temperature uniformity

Spatial-resolution, lumped-capacitance thermal model for cylindrical Li-ion batteries under high Biot number conditions

A two-dimensional mathematical model of dual-pulse laser ignition that self-consistently integrates Navier-Stokes, translational and vibrational energy, and neutral and charged species equations has been presented. The results showed that the ignition kernel dynamics depends on the shape and initial energy distribution in the energy spot created by the first ultraviolet laser pulse. The results also suggest that the ignition delay time and the flame kernel development depend on the laser intensity, vibrational-nonequilibrium, and initial electron number density. For the high initial degree of ionization, we have obtained ignition of the lean methane–air mixture with the equivalence ratio of 0.6. Vibrational-nonequilibrium taken into account by the Landau-Teller model leads to the slower ignition kernel growth and the significant increase in the ignition delay time. For the case modeled, a change in the overlap of the second laser with the focal point of the first laser pulse leads to the early split up of the kernel and the flame extinguishment.

Dual-pulse laser ignition model

Multiphase modeling approach for ionic liquids (ILs) based nanofluids: Improving the performance of heat transfer fluids (HTFs)

Atmospheric pressure microplasma devices have been the subject of considerable interest and research during the last decade. Most of the operation regime of the plasma discharges studied fall in the 'abnormal', 'normal' and 'corona' modes—increasing and a 'flat' voltage current characteristics. However, the negative differential resistance regime at atmospheric and high pressures has been less studied and possesses unique characteristics that can be employed for novel applications. In this work, the role of ion kinetics especially associated with trace impurities; on the self pulsing behavior has been investigated. Detailed numerical simulations have been conducted with a validated model for a helium-nitrogen feed gas mixture. Different oscillatory modes were observed where the discharge was found to undergo complete or partial relaxation. Trace amount of nitrogen was found to significantly alter the pulsing characteristics. External parameters influencing these self oscillations are also studied and aspects of the ion kinetics on the oscillatory behavior are discussed.

http://iopscience.iop.org/article/10.1088/0022-3727/49/14/145202/pdf

Rajib Mahamud

Papers

Reciprocating air flow for Li-ion battery thermal management to improve temperature uniformity

Spatial-resolution, lumped-capacitance thermal model for cylindrical Li-ion batteries under high Biot number conditions

Dual-pulse laser ignition model

Multiphase modeling approach for ionic liquids (ILs) based nanofluids: Improving the performance of heat transfer fluids (HTFs)

Ion kinetics and self pulsing in DC microplasma discharges at atmospheric and higher pressure