A simple rational model is proposed for discharge of batteries with aqueous electrolytes, based on Nernst equation. Details of electrode kinetics are not taken into account. Only a few overall parameters of the batter...A simple rational model is proposed for discharge of batteries with aqueous electrolytes, based on Nernst equation. Details of electrode kinetics are not taken into account. Only a few overall parameters of the battery are considered. A simple algorithm, with variable time step-length <span style="font-family:Verdana;">Δ</span><i><span style="font-family:Verdana;">t</span></i><span style="font-family:Verdana;">, is presented, for proposed model. The model is first applied to Daniel cell, in order to clar</span><span style="font-family:Verdana;">ify</span><span style="font-family:""><span style="font-family:Verdana;"> concepts and principles of battery operation. It is found that initial pinching, in time-history curve of voltage </span><i><span style="font-family:Verdana;">E-t</span></i><span style="font-family:Verdana;">, is due to initial under-concentration of product ion. Then, model is applied </span></span><span style="font-family:Verdana;">to</span><span> a lead-acid battery. In absence of an ion product, and in order to construct nominator of Nernst ratio, such an ion, with coefficient tending to zero, is assumed, thus yielding unity in nominator. Time-history curves of voltage, for various values of internal resistance, are compared with corresponding published experimental curves. Temperature effect on voltage-time curve is examined. Proposed model can be extended to other types of batteries, which can be considered as having aqueous electrolytes, too.</span>展开更多
The influence of magnetic field on the redox potentials of the Nernst equation. The author offered the new formula Nernst equation in a magnetic field. Our proposed formula takes into account the influence of the magn...The influence of magnetic field on the redox potentials of the Nernst equation. The author offered the new formula Nernst equation in a magnetic field. Our proposed formula takes into account the influence of the magnetic field on the redox processes.展开更多
The electric double layer(EDL),formed by charge adsorption at the electrolyte–electrode interface,constitutes the microenvironment governing electrochemical reactions.However,due to scale mismatch between the EDL thi...The electric double layer(EDL),formed by charge adsorption at the electrolyte–electrode interface,constitutes the microenvironment governing electrochemical reactions.However,due to scale mismatch between the EDL thickness and electrode topography,solving the two-dimensional(2D)nonhomogeneous Poisson–Nernst–Planck(N-PNP)equations remains computationally intractable.This limitation hinders understanding of fundamental phenomena such as curvature-driven instabilities in 2D EDL.Here,we propose a dimensionality-decomposition strategy embedding a fully connected neural network(FCNN)to solve 2D N-PNP equations,in which the FCNN is trained on key electrochemical parameters by reducing the electrostatic boundary into multiple equivalent 1D representations.Through a representative case of LiPF6 reduction on lithium metal half-cell,nucleus size is unexpectedly found to have an important influence on dendrite morphology and tip kinetics.This work paves the way for bridging nanoscale and macroscale simulations with expandability to 2D situations of other 1D EDL models.展开更多
Organic electrochemical transistors(OECTs)combine electron/ionic transport with organic semiconductor flexibility to connect biology and electronics.As they approach industrial use,optimizing performance requires accu...Organic electrochemical transistors(OECTs)combine electron/ionic transport with organic semiconductor flexibility to connect biology and electronics.As they approach industrial use,optimizing performance requires accurate modeling of their structure.This study presents a twodimensional(2D)OECT model based on Nernst-Planck-Poisson equations that explicitly includes volumetric capacitance(CV).Unlike previous models that ignore CV,our model highlights its essential role in OECT operation,allowing us to accurately match the measured output currents of PEDOT:PSS printed OECTs.We studied how parameters like diffusion coefficients of holes and ions,fixed anion concentration,and intrinsic capacitance affect transistor performance.We analyze existing OECT models,noting that different frameworks,despite varying assumptions,can reproduce data.This question relies solely on experimental agreement for validation.We argue that models should also be evaluated on their physical principles.To assist readers,we provide COMSOL.mph files for 1D and 2D OECT models for device design and optimization.展开更多
文摘A simple rational model is proposed for discharge of batteries with aqueous electrolytes, based on Nernst equation. Details of electrode kinetics are not taken into account. Only a few overall parameters of the battery are considered. A simple algorithm, with variable time step-length <span style="font-family:Verdana;">Δ</span><i><span style="font-family:Verdana;">t</span></i><span style="font-family:Verdana;">, is presented, for proposed model. The model is first applied to Daniel cell, in order to clar</span><span style="font-family:Verdana;">ify</span><span style="font-family:""><span style="font-family:Verdana;"> concepts and principles of battery operation. It is found that initial pinching, in time-history curve of voltage </span><i><span style="font-family:Verdana;">E-t</span></i><span style="font-family:Verdana;">, is due to initial under-concentration of product ion. Then, model is applied </span></span><span style="font-family:Verdana;">to</span><span> a lead-acid battery. In absence of an ion product, and in order to construct nominator of Nernst ratio, such an ion, with coefficient tending to zero, is assumed, thus yielding unity in nominator. Time-history curves of voltage, for various values of internal resistance, are compared with corresponding published experimental curves. Temperature effect on voltage-time curve is examined. Proposed model can be extended to other types of batteries, which can be considered as having aqueous electrolytes, too.</span>
文摘The influence of magnetic field on the redox potentials of the Nernst equation. The author offered the new formula Nernst equation in a magnetic field. Our proposed formula takes into account the influence of the magnetic field on the redox processes.
基金supported by the National Natural Science Foundation of China(Grant Nos.92472207,52472223,and 92572301)。
文摘The electric double layer(EDL),formed by charge adsorption at the electrolyte–electrode interface,constitutes the microenvironment governing electrochemical reactions.However,due to scale mismatch between the EDL thickness and electrode topography,solving the two-dimensional(2D)nonhomogeneous Poisson–Nernst–Planck(N-PNP)equations remains computationally intractable.This limitation hinders understanding of fundamental phenomena such as curvature-driven instabilities in 2D EDL.Here,we propose a dimensionality-decomposition strategy embedding a fully connected neural network(FCNN)to solve 2D N-PNP equations,in which the FCNN is trained on key electrochemical parameters by reducing the electrostatic boundary into multiple equivalent 1D representations.Through a representative case of LiPF6 reduction on lithium metal half-cell,nucleus size is unexpectedly found to have an important influence on dendrite morphology and tip kinetics.This work paves the way for bridging nanoscale and macroscale simulations with expandability to 2D situations of other 1D EDL models.
基金support from Advanced Functional Materials at Linköping Universitysupport from Swedish research Council(2024-04449)+1 种基金from the Knut and Alice Wallenberg Foundation(KAW)through the Wallenberg Wood Science Center 3.0(KAW 2021.0313)provided by the National Academic Infrastructure for Supercomputing in Sweden(NAISS)at NSC and PDC.
文摘Organic electrochemical transistors(OECTs)combine electron/ionic transport with organic semiconductor flexibility to connect biology and electronics.As they approach industrial use,optimizing performance requires accurate modeling of their structure.This study presents a twodimensional(2D)OECT model based on Nernst-Planck-Poisson equations that explicitly includes volumetric capacitance(CV).Unlike previous models that ignore CV,our model highlights its essential role in OECT operation,allowing us to accurately match the measured output currents of PEDOT:PSS printed OECTs.We studied how parameters like diffusion coefficients of holes and ions,fixed anion concentration,and intrinsic capacitance affect transistor performance.We analyze existing OECT models,noting that different frameworks,despite varying assumptions,can reproduce data.This question relies solely on experimental agreement for validation.We argue that models should also be evaluated on their physical principles.To assist readers,we provide COMSOL.mph files for 1D and 2D OECT models for device design and optimization.