Silicon has been investigated extensively as a promising anode material for rechargeable lithium-ion bat- teries. Understanding the failure mechanism of silicon-based anode electrodes for lithium-ion batteries is esse...Silicon has been investigated extensively as a promising anode material for rechargeable lithium-ion bat- teries. Understanding the failure mechanism of silicon-based anode electrodes for lithium-ion batteries is essential to solve the problem of low coulombic efficiency and capacity fading on cycling and also to further commercialize this very new energetic material in cells. To reach this goal, the structure changes of bulk silicon particles and electrode after cycling were studied using ex-situ scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The SEM images indicated that the microstructural changes of the bulk silicon particles during cycling led to a layer rupture of the electrode and then the breakdown of the conductive network and the failure of the electrode. The result contributes to the basic understanding of the failure mechanism of a bulk sil- icon anode electrode for lithium-ion batteries.展开更多
Both resource efficiency and application QoS have been big concerns of datacenter operators for a long time,but remain to be irreconcilable.High resource utilization increases the risk of resource contention between c...Both resource efficiency and application QoS have been big concerns of datacenter operators for a long time,but remain to be irreconcilable.High resource utilization increases the risk of resource contention between co-located workload,which makes latency-critical(LC)applications suffer unpredictable,and even unacceptable performance.Plenty of prior work devotes the effort on exploiting effective mechanisms to protect the QoS of LC applications while improving resource efficiency.In this paper,we propose MAGI,a resource management runtime that leverages neural networks to monitor and further pinpoint the root cause of performance interference,and adjusts resource shares of corresponding applications to ensure the QoS of LC applications.MAGI is a practice in Alibaba datacenter to provide on-demand resource adjustment for applications using neural networks.The experimental results show that MAGI could reduce up to 87.3%performance degradation of LC application when co-located with other antagonist applications.展开更多
The polyvinyl carbonate(PVC)polymer solid electrolyte can be in-situ generated in the assembled lithium-ion battery(LIBs);however,its rigid characteristic leads to uneven interface contact between electrolyte and elec...The polyvinyl carbonate(PVC)polymer solid electrolyte can be in-situ generated in the assembled lithium-ion battery(LIBs);however,its rigid characteristic leads to uneven interface contact between electrolyte and electrodes.In this work,trimethyl phosphate(TMP)is introduced into the precursor solution for in-situ generation of flexible PVC solid electrolyte to improve the interfacial contact of elec-trolyte and electrodes together with ionic conductivity.The PVC-TMP electrolyte exhibits good interface compatibility with the lithium metal anode,and the lithium symmetric battery based on PVC-TMP electrolyte shows no obvious polarization within 1000 h cycle.As a consequence,the initial interfacial resistance of battery greatly decreases from 278Ω(LiFePO_(4)(LFP)/PVC/Li)to 93Ω(LFP/PVC-TMP/Li)at 50℃,leading to an improved cycling stability of the LFP/PVC-TMP/Li battery.Such in-situ preparation of solid electrolyte within the battery is demonstrated to be very significant for commercial application.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 51004016 and 51004017)the National High Technology Research and Development Program of China (Nos.2012AA110102 and 2011AA11A269)
文摘Silicon has been investigated extensively as a promising anode material for rechargeable lithium-ion bat- teries. Understanding the failure mechanism of silicon-based anode electrodes for lithium-ion batteries is essential to solve the problem of low coulombic efficiency and capacity fading on cycling and also to further commercialize this very new energetic material in cells. To reach this goal, the structure changes of bulk silicon particles and electrode after cycling were studied using ex-situ scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The SEM images indicated that the microstructural changes of the bulk silicon particles during cycling led to a layer rupture of the electrode and then the breakdown of the conductive network and the failure of the electrode. The result contributes to the basic understanding of the failure mechanism of a bulk sil- icon anode electrode for lithium-ion batteries.
基金This work is supported in part by the National Key Research and Development Program of China under Grant No.2016YFB1000201the National Natural Science Foundation of China under Grant Nos.61420106013 and 61702480the Youth Innovation Promotion Association of Chinese Academy of Sciences and Alibaba Innovative Research(AIR)Program.
文摘Both resource efficiency and application QoS have been big concerns of datacenter operators for a long time,but remain to be irreconcilable.High resource utilization increases the risk of resource contention between co-located workload,which makes latency-critical(LC)applications suffer unpredictable,and even unacceptable performance.Plenty of prior work devotes the effort on exploiting effective mechanisms to protect the QoS of LC applications while improving resource efficiency.In this paper,we propose MAGI,a resource management runtime that leverages neural networks to monitor and further pinpoint the root cause of performance interference,and adjusts resource shares of corresponding applications to ensure the QoS of LC applications.MAGI is a practice in Alibaba datacenter to provide on-demand resource adjustment for applications using neural networks.The experimental results show that MAGI could reduce up to 87.3%performance degradation of LC application when co-located with other antagonist applications.
基金financially supported by the National Natural Science Foundation of China (No.21676017)the Opening Project of State Key Laboratory of Advanced Chemical Power Sources (No.SKL-ACPS-C-27)the Opening Project of State Key Laboratory of Organic-Inorganic Composites
文摘The polyvinyl carbonate(PVC)polymer solid electrolyte can be in-situ generated in the assembled lithium-ion battery(LIBs);however,its rigid characteristic leads to uneven interface contact between electrolyte and electrodes.In this work,trimethyl phosphate(TMP)is introduced into the precursor solution for in-situ generation of flexible PVC solid electrolyte to improve the interfacial contact of elec-trolyte and electrodes together with ionic conductivity.The PVC-TMP electrolyte exhibits good interface compatibility with the lithium metal anode,and the lithium symmetric battery based on PVC-TMP electrolyte shows no obvious polarization within 1000 h cycle.As a consequence,the initial interfacial resistance of battery greatly decreases from 278Ω(LiFePO_(4)(LFP)/PVC/Li)to 93Ω(LFP/PVC-TMP/Li)at 50℃,leading to an improved cycling stability of the LFP/PVC-TMP/Li battery.Such in-situ preparation of solid electrolyte within the battery is demonstrated to be very significant for commercial application.