A systematic model-based degradation behavior recognition and health monitoring method for lithium-ion batteries

Determination of the Optimum Heat Transfer Coefficient and Temperature Rise Analysis for a Lithium-Ion Battery under the Conditions of Harbin City Bus Driving Cycles

“…The internal resistance of the battery in Equation (12) can be obtained by the hybrid pulse power characterization (HPPC) test [22]. The entropy coefficient can be obtained by the following method [23,24]: the battery open circuit voltage (UOCV) is measured under fixed SOC (state of charge) conditions and different ambient temperature, and the relation between UOCV, Ts, and SOC is shown in Figure 5.…”

“…According to the thermal model developed in this study, the heat transfer coefficient that ensures the temperature of battery is below 35 • C after working for eight cycles under the operation conditions of the three Harbin bus lines can be obtained with different ambient temperature, as shown in Figures 11-13. The data were fitted by the least squares method, to obtain the quantitative relationship between the optimum heat transfer coefficient and the ambient temperature of the battery under the operation conditions of the three Harbin bus lines, which are shown in Equations (20)- (22). Figure 11 and Equation (20) show that natural convection can meet the cooling requirements of the batteries under the regular lines when the ambient temperature is below 28 • C, while when the ambient temperature is 30 • C, the heat transfer coefficient should be at least 12 W/m 2 K. Figure 12 and Equation (21) show that when the ambient temperature is below 23 • C, the natural convection can meet the cooling requirements of the batteries in the BRT lines, while when the ambient temperature is 30 • C, the heat transfer coefficient should be at least 22 W/m 2 K. Figure 13 and Equation (22) batteries in the BRT lines, while when the ambient temperature is 30 °C, the heat transfer coefficient should be at least 22 W/m 2 K. Figure 13 and Equation (22) show that when the ambient temperature is below 20 °C, the natural convection can meet the cooling requirements of batteries under the operation conditions of the suburban lines, while when the ambient temperature is 30 °C, the heat transfer coefficient should be at least 32 W/m 2 K. This analysis shows that the heat transfer coefficient that meets the requirements of battery thermal management equals the cubic power function of the ambient temperature.…”

Using SoC Online Correction Method Based on Parameter Identification to Optimize the Operation Range of NI-MH Battery for Electric Boat

“…The effectiveness of the degradation state recognition method to estimate the remaining capacity online had been validated [41]. According to second-order RC electrical equivalent circuit model and Kirchhoff's voltage theorem mathematical expression for the load voltage U L is available as follows:…”

Entropy-Based Voltage Fault Diagnosis of Battery Systems for Electric Vehicles

“…A number of methods to estimate faults have been proposed and studies on this topic are mainly based on process parameter estimations, state estimations, experience knowledge and other methods [9][10][11][12]. Sun et al [13] described a method to diagnose the degradation of lead-acid battery units caused by internal shorts, opening of internal shorts or cell reversal.…”