To ensure a long-term safety and reliability of electric vehicle and energy storage system,an accurate estimation of the state of health(SOH)for lithium-ion battery is important.In this study,a method for estimating t...To ensure a long-term safety and reliability of electric vehicle and energy storage system,an accurate estimation of the state of health(SOH)for lithium-ion battery is important.In this study,a method for estimating the lithium-ion battery SOH was proposed based on an improved extreme learning machine(ELM).Input weights and hidden layer biases were generated randomly in traditional ELM.To improve the estimation accuracy of ELM,the differential evolution algorithm was used to optimize these parameters in feasible solution spaces.First,incremental capacity curves were obtained by incremental capacity analysis and smoothed by Gaussian filter to extract health interests.Then,the ELM based on differential evolution algorithm(DE-ELM model)was used for a lithium-ion battery SOH estimation.At last,four battery historical aging data sets and one random walk data set were employed to validate the prediction performance of DE-ELM model.Results show that the DE-ELM has a better performance than other studied algorithms in terms of generalization ability.展开更多
基于目前汽车产业的轻量化需求,先进高强钢板被广泛应用在汽车板中。为了保护高强钢板的表面不被腐蚀,其表面需要采用热镀锌或锌层合金化等表面处理技术,利用锌的阳极保护对钢板进行保护。但是由于锌的熔点为440-460°C,因此对高强...基于目前汽车产业的轻量化需求,先进高强钢板被广泛应用在汽车板中。为了保护高强钢板的表面不被腐蚀,其表面需要采用热镀锌或锌层合金化等表面处理技术,利用锌的阳极保护对钢板进行保护。但是由于锌的熔点为440-460°C,因此对高强钢板进行电阻点焊时,会发生液态金属致脆(Liquid Metal Embrittlement, LME)现象。此现象主要是由于锌或锌的金属间化合物在点焊过程中发生局部熔化,进而在点焊过程中的复杂应力场的作用下,沿着晶界扩展,进而导致晶界出现沿晶微裂纹的现象。本文提出采用高温三点弯的实验模拟方法,近似模拟出了Zn及Zn合金在高温复杂应力下沿着晶界浸润的液态金属致脆现象。展开更多
文摘To ensure a long-term safety and reliability of electric vehicle and energy storage system,an accurate estimation of the state of health(SOH)for lithium-ion battery is important.In this study,a method for estimating the lithium-ion battery SOH was proposed based on an improved extreme learning machine(ELM).Input weights and hidden layer biases were generated randomly in traditional ELM.To improve the estimation accuracy of ELM,the differential evolution algorithm was used to optimize these parameters in feasible solution spaces.First,incremental capacity curves were obtained by incremental capacity analysis and smoothed by Gaussian filter to extract health interests.Then,the ELM based on differential evolution algorithm(DE-ELM model)was used for a lithium-ion battery SOH estimation.At last,four battery historical aging data sets and one random walk data set were employed to validate the prediction performance of DE-ELM model.Results show that the DE-ELM has a better performance than other studied algorithms in terms of generalization ability.
文摘基于目前汽车产业的轻量化需求,先进高强钢板被广泛应用在汽车板中。为了保护高强钢板的表面不被腐蚀,其表面需要采用热镀锌或锌层合金化等表面处理技术,利用锌的阳极保护对钢板进行保护。但是由于锌的熔点为440-460°C,因此对高强钢板进行电阻点焊时,会发生液态金属致脆(Liquid Metal Embrittlement, LME)现象。此现象主要是由于锌或锌的金属间化合物在点焊过程中发生局部熔化,进而在点焊过程中的复杂应力场的作用下,沿着晶界扩展,进而导致晶界出现沿晶微裂纹的现象。本文提出采用高温三点弯的实验模拟方法,近似模拟出了Zn及Zn合金在高温复杂应力下沿着晶界浸润的液态金属致脆现象。
