The current collector fracture failure of lithium-ion batteries(LIBs)occurs during its winding production process frequently,and the consequent damages are usually large,but little research has been conducted on this ...The current collector fracture failure of lithium-ion batteries(LIBs)occurs during its winding production process frequently,and the consequent damages are usually large,but little research has been conducted on this phenomenon.This work stems from the difficulty and obstacles in the winding process of actual production of LIBs.The fracture failure of the current collectors is easily caused by the evolution and mutation of the mechanical behavior during the winding process,resulting in safety hazards and poor efficiency.The purpose of this work is to reveal the evolution and distribution mechanism of circumferential strain of the current collectors on the fracture failure under the constraint of winding process.Experimental tests,finite element calculations and theoretical model are used to study the evolution and distribution of circumferential strain.The dynamic evolution process of circumferential strain is tested accurately,and the mechanism of fracture failure of current collectors is revealed.The criterion for current collector strength is proposed based on the results of strain analysis and SEM observation.展开更多
反应堆一回路中部分管道长期承受冷热流体的交替冲刷,局部可能出现的热分层现象使管道中的热应力进一步加大,由此产生的应力集中及疲劳问题可能危害反应堆的安全运行。基于热流固多物理场耦合方法结合ASME(American Society of Mechanic...反应堆一回路中部分管道长期承受冷热流体的交替冲刷,局部可能出现的热分层现象使管道中的热应力进一步加大,由此产生的应力集中及疲劳问题可能危害反应堆的安全运行。基于热流固多物理场耦合方法结合ASME(American Society of Mechanical Engineers)规范中适用于核一级承压设备的相关标准和分析流程,对某型号反应堆的管道系统开展了结构强度校核及疲劳分析,数值结果表明:当前工况参数及出现次数叠加作用下管道系统的应力分类结果满足规范要求,不会出现不可逆的结构损伤,且关键结构不连续位置的疲劳累积使用因子均小于1,未出现累积使用因子超限问题。展开更多
基金National Natural Science Foundation of China(12002183)Postdoctoral Science Foundation(2019TQ0171,2020M670304)Beijing Natural Science Foundation(Grant Nos.16L00001 and 2182065)are Rratefullv acknowledged.
文摘The current collector fracture failure of lithium-ion batteries(LIBs)occurs during its winding production process frequently,and the consequent damages are usually large,but little research has been conducted on this phenomenon.This work stems from the difficulty and obstacles in the winding process of actual production of LIBs.The fracture failure of the current collectors is easily caused by the evolution and mutation of the mechanical behavior during the winding process,resulting in safety hazards and poor efficiency.The purpose of this work is to reveal the evolution and distribution mechanism of circumferential strain of the current collectors on the fracture failure under the constraint of winding process.Experimental tests,finite element calculations and theoretical model are used to study the evolution and distribution of circumferential strain.The dynamic evolution process of circumferential strain is tested accurately,and the mechanism of fracture failure of current collectors is revealed.The criterion for current collector strength is proposed based on the results of strain analysis and SEM observation.
文摘反应堆一回路中部分管道长期承受冷热流体的交替冲刷,局部可能出现的热分层现象使管道中的热应力进一步加大,由此产生的应力集中及疲劳问题可能危害反应堆的安全运行。基于热流固多物理场耦合方法结合ASME(American Society of Mechanical Engineers)规范中适用于核一级承压设备的相关标准和分析流程,对某型号反应堆的管道系统开展了结构强度校核及疲劳分析,数值结果表明:当前工况参数及出现次数叠加作用下管道系统的应力分类结果满足规范要求,不会出现不可逆的结构损伤,且关键结构不连续位置的疲劳累积使用因子均小于1,未出现累积使用因子超限问题。