<p>Lithium-ion batteries are regarded as the batteries that could potentially change the world. From consumer electronics and electric vehicles to energy storage systems and aerospace applications, Li-ion based batteries have become the norm. Although these batteries show a lot of promise to rid the world of several challenges in the future, there are still a few shortcomings of this battery that need to be addressed. It is also important to note the recent accidents caused due to the explosion of these lithium-ion batteries, to name a few: Samsung Galaxy Note 7 explosion, e-cigarettes battery explosion, overheating of lithium batteries present in Apple MacBook Pro laptop. This calls for a more reliable and accurate Battery Management System (BMS). One of the major shortcomings in today’s available battery management systems is the accuracy of the measurement of charge present in lithium-ion batteries, termed as State-of-Charge (SoC) and State-of-Energy (SoE) of the battery. </p> <p>To address this problem, a highly sensitive and a high-resolution system is developed to estimate the State-of-Charge based on the changes in impedance of a sensor coil which is caused due to the effect of Eddy Current Power Loss in the battery. The redox reaction taking place inside a battery suggest that lithium ions are exchanged back-and-forth between anode and cathode during an event of charging and/or discharging of the battery. This gives rise to change in electrical resistivity of the battery electrode materials. A sensor coil which is excited with an AC magnetic field induces Eddy currents on the internal components of the battery. Based on the change in resistivity of the electrode materials, eddy current and hence the power loss due to Eddy currents change. This in turn changes the complex impedance of the sensor coil, which is mapped to estimate the SoC of the battery. The results confirm the superiority of the proposed technique in terms of sensitivity, resolution, computational complexity and cost of the measured SoC in comparison with other existing methods of estimating SoC. This can be a potential method to estimate SoE of the battery as well. </p>

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-03-23T01:44:32Z No. of bitstreams: 1 GUSTAVO GOMES SAMPAIO CURSINO - TESE PPGEQ 2016.pdf: 5939681 bytes, checksum: 518baf4150ea2fb7085706252276b9fa (MD5) / Made available in DSpace on 2018-03-23T01:44:32Z (GMT). No. of bitstreams: 1 GUSTAVO GOMES SAMPAIO CURSINO - TESE PPGEQ 2016.pdf: 5939681 bytes, checksum: 518baf4150ea2fb7085706252276b9fa (MD5) Previous issue date: 2016-04-18 / Este trabalho teve o propósito de determinar o comportamento dos gases na seção de radiação de um combustor de ar que pertence a uma planta industrial. O corpo metálico do equipamento rompeu em seu primeiro ano de operação, devido a um problema conceitual em sua geometria. A fluidodinâmica computacional (CFD), por meio do método dos volumes finitos, foi utilizada para desenvolver um modelo tridimensional que pudesse reproduzir o perfil de temperatura e o comportamento do fluxo do ar de combustão no equipamento. Na simulação, através do uso do software ANSYS CFX, foram utilizados: (i) o modelo de turbulência Reynolds Stress Model (RSM); (ii) as malhas hexaédrica, tetraédrica e prismática; (iii) o modelo de radiação P-1; e (iv) o modelo de combustão Eddy Dissipation Concept (EDC). Como resultado, foram apresentadas quatro possíveis mudanças na geometria do combustor de ar que, caso adotadas, eliminariam os riscos de novas falhas e garantiriam a continuidade operacional da unidade de processo. / This paper has the objective to describe the behavior of the flow and temperature of the flue gas in the radiation section of the vessel used to preheat air in a combustor. The equipment failed in its first operational year, due to a conceptual problem in its geometry. The CFD code based on finite volume method was applied to simulate the physical model of combustor using the ANSYS CFX software, reproducing the main features of the preheater. The simulation had considered: (i) Reynolds Stress Model (RSM) as turbulence model, (ii) The meshes applied were the hexahedral, tetrahedral and prismatic, (iii) P-1 was used as the radiation model and (iv) Eddy Dissipation Concept (EDC) as combustion model. Through the simulation was possible to propose four different kind of combustor geometry modification, that the application of anyone of them would eliminate the risk of new failures, ensuring the unit production availability.