Life prediction and reliability assessment of lithium secondary batteries

Synthesis and properties of gel polymer electrolyte membranes based on novel comb-like methyl methacrylate copolymers

“…Lithium-ion batteries with high energy density, power capability, long recycling life and low self-discharge rate are used to power portable electronic devices such as cellular phones and laptop computers and have long been considered as possible power source for electric vehicle (EV), hybrid electric vehicle (HEV) and high efficiency energy-storage systems [1][2][3][4]. Gel polymer electrolyte (GPE), possessing not only the high conductivity of liquid electrolytes, but also the good mechanical properties of solid electrolytes, have received an upsurge of interest in view of their electrochemical and physical properties for the applications in lithium batteries in recent years [5,6].…”

Prediction of State-of-Health for Nickel-Metal Hydride Batteries by a Curve Model Based on Charge-Discharge Tests

“…After an interval of 1800 s, the next cycle of charge-discharge test was started. When the C discharge of the test cells fell to 80% of the initial capacity, the charge-discharge tests were terminated [45]. The failure capacity is still defined as 0.8C rated in this paper for convenient applications.…”

Life probability distribution model of mechanical components with the number of load application as life parameter

“…As long as the parameters of strength, stress, strength degradation, and so on are known, the life probabilistic distribution functions of components can be calculated with equations (8) and (9), and the mean life, reliability, and failure rate of component can also be obtained with equations (10)-(12), respectively. Additionally, with equation (9) or (11), the reliable life of component can be determined.…”

“…When the stress of component is submitted to the normal distribution with mean of 800 MPa and SD of 100 MPa, the original strength is also submitted to the normal distribution with mean of 500 MPa and SD of 60 MPa, and strength degenerates as d (n) = d À (d À s)((n À 1)=12000) 1:5 ; the curves of probability density function and cumulative distribution function of life of component calculated with equations (8) and (9) are shown in Figures 5 and 6, respectively, and the curves of reliability and failure rate of component calculated with equations (11) and (12) are shown in Figures 7 and 8, respectively. In this case, the failure probability density of components in the initial stage is higher, and then it begins to decrease as the number of load application, but as the number of load application increases further, it increases first and then decreases.…”