All-solid-state lithium batteries(ASSLBs)are regarded as the representative of next-generation energy storage technology.It can solve the flammability hazard of liquid lithium batteries and their theoretical energy de...All-solid-state lithium batteries(ASSLBs)are regarded as the representative of next-generation energy storage technology.It can solve the flammability hazard of liquid lithium batteries and their theoretical energy density can reach exceeding 500 Wh·kg^(-1).Silicon is one of the most attractive anode materials for high-energy ASSLBs because of its high theoretical capacity and low working potential.However,Si anode faces two key problems in practical applications.Firstly,the side reaction between Si and sulfide-based solid-state electrolytes is serious,which can form unstable interfacial phases,significantly increase interfacial impedance and deplete active lithium.Secondly,electrical/ionic contact loss caused by volume change of Si electrode during lithiation/delithiation process results in significant initial capacity loss and poor cycling stability.For this reason,a simple liquidphase approach was taken to form Li_(x)SiS_(y)layer-coated Si nanoparticles in-situ,and composite electrodes were prepared in this way.High initial coulombic efficiency(ICE)and stable cyclability for sulfide-based ASSLBs can be achieved.The results show that the Si@Li_(x)SiS_(y)-Li_(3)PS_(4)-C composite electrode exhibits a higher ICE of 77.5%at 0.13 mA·cm^(-2)compared to that of 55.9%for Si-Li_(3)PS_(4)-C electrode and a more stable cycling performance without external pressure.This indicates that the direct contact between Si and Li_(3)PS_(4)electrolyte is effectively blocked by coating with a Li_(x)SiS_(y)layer.Stable interface between Si and Li_(3)PS_(4)electrolyte can be obtained and prevent the side reactions between them.Both the stable interface and partial prelithiation of Si electrode is favorable for high initial reversibility.At the same time the presence of the coating layer reduces the mechanical stress due to the volume change of the Si particles and ensures a good stress relief.The greatly improved interfacial stability and favorable stress release ensured by the conformal coating layer can thus lead to good electrochemical performance of Si electrode in ASSLBs.展开更多
针对高维小样本的DNA微阵列数据多分类问题,提出一种基于ReliefF和蚁群算法的特征基因选择方法(ReliefF and ant colony optimization,Re FACO)。该方法首先采用ReliefF算法评估特征权重,根据阈值筛选出无关基因;然后引入改进的蚁群算法...针对高维小样本的DNA微阵列数据多分类问题,提出一种基于ReliefF和蚁群算法的特征基因选择方法(ReliefF and ant colony optimization,Re FACO)。该方法首先采用ReliefF算法评估特征权重,根据阈值筛选出无关基因;然后引入改进的蚁群算法,在迭代改进的过程中寻找最优基因子集;最后利用经典分类算法对维数约简后的数据分类识别。经实验证明,该方法可有效地剔除无关和冗余基因,并利用较少特征基因达到较高多分类效果。展开更多
基金National Key R&D Program of China(2022YFB3506300)Guangdong-Foshan Joint Fund(2023A1515140091)Guangdong High-level Innovation Institute Project(2021B0909050001)。
文摘All-solid-state lithium batteries(ASSLBs)are regarded as the representative of next-generation energy storage technology.It can solve the flammability hazard of liquid lithium batteries and their theoretical energy density can reach exceeding 500 Wh·kg^(-1).Silicon is one of the most attractive anode materials for high-energy ASSLBs because of its high theoretical capacity and low working potential.However,Si anode faces two key problems in practical applications.Firstly,the side reaction between Si and sulfide-based solid-state electrolytes is serious,which can form unstable interfacial phases,significantly increase interfacial impedance and deplete active lithium.Secondly,electrical/ionic contact loss caused by volume change of Si electrode during lithiation/delithiation process results in significant initial capacity loss and poor cycling stability.For this reason,a simple liquidphase approach was taken to form Li_(x)SiS_(y)layer-coated Si nanoparticles in-situ,and composite electrodes were prepared in this way.High initial coulombic efficiency(ICE)and stable cyclability for sulfide-based ASSLBs can be achieved.The results show that the Si@Li_(x)SiS_(y)-Li_(3)PS_(4)-C composite electrode exhibits a higher ICE of 77.5%at 0.13 mA·cm^(-2)compared to that of 55.9%for Si-Li_(3)PS_(4)-C electrode and a more stable cycling performance without external pressure.This indicates that the direct contact between Si and Li_(3)PS_(4)electrolyte is effectively blocked by coating with a Li_(x)SiS_(y)layer.Stable interface between Si and Li_(3)PS_(4)electrolyte can be obtained and prevent the side reactions between them.Both the stable interface and partial prelithiation of Si electrode is favorable for high initial reversibility.At the same time the presence of the coating layer reduces the mechanical stress due to the volume change of the Si particles and ensures a good stress relief.The greatly improved interfacial stability and favorable stress release ensured by the conformal coating layer can thus lead to good electrochemical performance of Si electrode in ASSLBs.
文摘针对高维小样本的DNA微阵列数据多分类问题,提出一种基于ReliefF和蚁群算法的特征基因选择方法(ReliefF and ant colony optimization,Re FACO)。该方法首先采用ReliefF算法评估特征权重,根据阈值筛选出无关基因;然后引入改进的蚁群算法,在迭代改进的过程中寻找最优基因子集;最后利用经典分类算法对维数约简后的数据分类识别。经实验证明,该方法可有效地剔除无关和冗余基因,并利用较少特征基因达到较高多分类效果。
