Thermal runaway(TR)is a critical issue hindering the large-scale application of lithium-ion batteries(LIBs).Understanding the thermal safety behavior of LIBs at the cell and module level under different state of charg...Thermal runaway(TR)is a critical issue hindering the large-scale application of lithium-ion batteries(LIBs).Understanding the thermal safety behavior of LIBs at the cell and module level under different state of charges(SOCs)has significant implications for reinforcing the thermal safety design of the lithium-ion battery module.This study first investigates the thermal safety boundary(TSB)correspondence at the cells and modules level under the guidance of a newly proposed concept,safe electric quantity boundary(SEQB).A reasonable thermal runaway propagation(TRP)judgment indicator,peak heat transfer power(PHTP),is proposed to predict whether TRP occurs.Moreover,a validated 3D model is used to quantitatively clarify the TSB at different SOCs from the perspective of PHTP,TR trigger temperature,SOC,and the full cycle life.Besides,three different TRP transfer modes are discovered.The interconversion relationship of three different TRP modes is investigated from the perspective of PHTP.This paper explores the TSB of LIBs under different SOCs at both cell and module levels for the first time,which has great significance in guiding the thermal safety design of battery systems.展开更多
A three-dimensional （3D） polymer thermo-optic （TO） 1 × 4 waveguide switch matrix based on vertical couplers is demonstrated. It consists of four basic 3D switch units and because of its 3D structure, its cons...A three-dimensional （3D） polymer thermo-optic （TO） 1 × 4 waveguide switch matrix based on vertical couplers is demonstrated. It consists of four basic 3D switch units and because of its 3D structure, its construction is compact, only 9 mm in length; moreover, the control logic of the entire switch is very simple, the light signal can be easily switched to any output port by operating only a single switch unit. The finished devices exhibit a switching extinction ratio greater than 21 dB for all of four output ports and the crosstalk between two adjacent output ports is lower than -19 dB. The rise time and the fall time of the switch matrix are 0.8ms and 1.4ms, respectively. The required electrical power to initiate the switching function for M1 switching units is about 50mW.展开更多
We propose a novel structure and unique sensing mechanism bio-chemical sensor which is fabricated by a polymer long-period waveguide grating with the detection liquid directly as the waveguide cladding.Quantitative de...We propose a novel structure and unique sensing mechanism bio-chemical sensor which is fabricated by a polymer long-period waveguide grating with the detection liquid directly as the waveguide cladding.Quantitative detection is realized from analyzing the output absorption spectrum and resonant wavelength shift related to the liquid detection concentration.The proposed polymer long-period waveguide grating based liquid refractive-index sensor is developed experimentally,the high sensitivity of 1.01×10^4nm/RIU is achieved,and the temperature stability coefficient is 1.47nm/℃.Theoretically and experimentally,this work has been demonstrated to have potential application in chemical and biological detections and may provide an important technical support for solving today's increasingly serious civil problems such as food safety and drug safety, which will also have the important scientific significance and application prospects.展开更多
We analyze and explore the potential of using a polymer horizontal slot waveguide as light-analyte interactive region to implement a low-cost and highly sensitive liquid refractive index sensor.Numerical analysis show...We analyze and explore the potential of using a polymer horizontal slot waveguide as light-analyte interactive region to implement a low-cost and highly sensitive liquid refractive index sensor.Numerical analysis shows that the optimized polymer horizontal slot waveguide is able to realize high waveguide sensitivity.With the optimized horizontal slot waveguide,polymer liquid refractive index sensors based on Mach-Zehnder interferometer(MZI)and microring resonator(MRR)are then investigated numerically,and the results show that the MZI-based sensor can achieve high sensitivity of 17024 nm/RIU and low limit of detection(LOD)of 1.76´10^(-6) RIU while the MRR-based sensor can achieve the sensitivity of 177 nm/RIU and the LOD of 1.69´10^(-4) RIU with a very small footprint.Compared with the sensors employing conventional silicon or silicon nitride vertical slot waveguide,the sensors employing polymer horizontal slot waveguide exhibit comparable performances but simpler and lower fabrication costs.展开更多
基金supported by the National Natural Science Foundation of China(No.U20A20310 and No.52176199)sponsored by the Program of Shanghai Academic/Technology Research Leader(No.22XD1423800)。
文摘Thermal runaway(TR)is a critical issue hindering the large-scale application of lithium-ion batteries(LIBs).Understanding the thermal safety behavior of LIBs at the cell and module level under different state of charges(SOCs)has significant implications for reinforcing the thermal safety design of the lithium-ion battery module.This study first investigates the thermal safety boundary(TSB)correspondence at the cells and modules level under the guidance of a newly proposed concept,safe electric quantity boundary(SEQB).A reasonable thermal runaway propagation(TRP)judgment indicator,peak heat transfer power(PHTP),is proposed to predict whether TRP occurs.Moreover,a validated 3D model is used to quantitatively clarify the TSB at different SOCs from the perspective of PHTP,TR trigger temperature,SOC,and the full cycle life.Besides,three different TRP transfer modes are discovered.The interconversion relationship of three different TRP modes is investigated from the perspective of PHTP.This paper explores the TSB of LIBs under different SOCs at both cell and module levels for the first time,which has great significance in guiding the thermal safety design of battery systems.
文摘A three-dimensional （3D） polymer thermo-optic （TO） 1 × 4 waveguide switch matrix based on vertical couplers is demonstrated. It consists of four basic 3D switch units and because of its 3D structure, its construction is compact, only 9 mm in length; moreover, the control logic of the entire switch is very simple, the light signal can be easily switched to any output port by operating only a single switch unit. The finished devices exhibit a switching extinction ratio greater than 21 dB for all of four output ports and the crosstalk between two adjacent output ports is lower than -19 dB. The rise time and the fall time of the switch matrix are 0.8ms and 1.4ms, respectively. The required electrical power to initiate the switching function for M1 switching units is about 50mW.
基金the National Natural Science Foundation of China(NSFC)(Grant No.61505020)the Fundamental Research Funds for the Central Universities(Grant No. ZYGX2016J005).
文摘We propose a novel structure and unique sensing mechanism bio-chemical sensor which is fabricated by a polymer long-period waveguide grating with the detection liquid directly as the waveguide cladding.Quantitative detection is realized from analyzing the output absorption spectrum and resonant wavelength shift related to the liquid detection concentration.The proposed polymer long-period waveguide grating based liquid refractive-index sensor is developed experimentally,the high sensitivity of 1.01×10^4nm/RIU is achieved,and the temperature stability coefficient is 1.47nm/℃.Theoretically and experimentally,this work has been demonstrated to have potential application in chemical and biological detections and may provide an important technical support for solving today's increasingly serious civil problems such as food safety and drug safety, which will also have the important scientific significance and application prospects.
基金This work is supported by the National Natural Science Foundation of China(NSFC)(Grant No.61505020)the Opened Fund of the State Key Laboratory of Integrated Optoelectronics(Grant No.IOSKL2018KF12).
文摘We analyze and explore the potential of using a polymer horizontal slot waveguide as light-analyte interactive region to implement a low-cost and highly sensitive liquid refractive index sensor.Numerical analysis shows that the optimized polymer horizontal slot waveguide is able to realize high waveguide sensitivity.With the optimized horizontal slot waveguide,polymer liquid refractive index sensors based on Mach-Zehnder interferometer(MZI)and microring resonator(MRR)are then investigated numerically,and the results show that the MZI-based sensor can achieve high sensitivity of 17024 nm/RIU and low limit of detection(LOD)of 1.76´10^(-6) RIU while the MRR-based sensor can achieve the sensitivity of 177 nm/RIU and the LOD of 1.69´10^(-4) RIU with a very small footprint.Compared with the sensors employing conventional silicon or silicon nitride vertical slot waveguide,the sensors employing polymer horizontal slot waveguide exhibit comparable performances but simpler and lower fabrication costs.
