Prediction of future capacity and internal resistance of Li-ion cells from one cycle of input data

There is a large demand for models able to predict the future capacity retention and internal resistance(IR)of Lithium-ion battery cells with as little testing as possible.We provide a data-centric model accurately predicting a cell’s entire capacity and IR trajectory from one single cycle of input data.This represents a significant reduction in the amount of input data needed over previous works.Our approach characterises the capacity and IR curve through a small number of key points,which,once predicted and interpolated,describe the full curve.With this approach the remaining useful life is predicted with an 8.6%mean absolute percentage error when the input-cycle is within the first 100 cycles.

An explicit compound Poisson process-based shock deterioration model for reliability assessment of aging structures

Existing structures may suffer from resistance deterioration due to repeated attacks. The modeling of resistance deterioration is a critical ingredient in the reliability assessment and service life prediction of these degraded structures. In this paper, an explicit compound Poisson process-based model is developed to describe the shock deterioration of structural resistance, where the magnitude of each shock deterioration increment is modeled by a Gamma-distributed random variable. The moments(mean value and variance) and the distribution function of the cumulative shock deterioration are derived in a closed form, based on a proposed W-function. A method for the efficient calculation of the W-function is presented,which reduces to the Bessel type I function if the shock deterioration increment is exponentially distributed(a special case of Gamma distribution). The proposed shock deterioration model is applicable to either a stationary or a nonstationary Poisson process of random jumps.Subsequently, the overall resistance deterioration is modeled as the linear combination of gradual and shock deteriorations, based on which the proposed model can be used in the timedependent reliability assessment of aging structures efficiently. A numerical example is presented to demonstrate the applicability of the proposed deterioration model by estimating the time-dependent reliability of an aging bridge. It is found that a smaller threshold for the degraded resistance leads to greater mean value and standard deviation of the time to failure,and this effect is enhanced by a smaller occurrence rate of the shock deterioration.

Comparison effects of lanthanum stearate and antioxidants in epoxidized natural rubber

This work studied possibilities of using lanthanum stearate（LaS t） as an antioxidant in epoxidized natural rubber containing 25 mol.% expoxidation（ENR25） compounds. For comparison purposes, two commercial antioxidant 4010 NA and MB were also used. The influence of LaS t, antioxidant 4010 NA and MB on cure characteristics, mechanical properties, crosslink density, hot air aging and thermo-oxidative degradation were studied. The results indicated that the incorporation of LaS t and antioxidants could accelerate the vulcanization of ENR. The ENR vulcanizates with antioxidant MB had better mechanical properties than 4010 NA and LaS t. Compared with antioxidant 4010 NA and MB, the ENR25 vulcanizates with the addition of LaS t exhibited the best hot air aging resistance and thermo-oxidative stability.