Effect Of Electrode Thickness Research Articles

Comparison and optimization of electrochemical and thermal performances of SOFC with different configurations of a metal foam flow field

The effects of different configurations of a metal foam flow field on current density and temperature gradient of a single channel solid oxide fuel cell (SOFC) are investigated, and the overall performance of the optimum configuration is optimized. First, model A (conventional channel-rib flow field) is compared with three different configurations (i.e., model B with metal foam flow field only at anode, model C with that only at cathode, and model D at both). Although model C achieves the highest current density, its temperature is also fairly high. Although model B achieves the lowest temperature gradient, its current density is also fairly low. Model D performs well in both current density and temperature gradient. Then, the effect of electrode thickness and metal foam thickness on the performance of model D is investigated. The Ohmic polarization of model D remains almost constant with different electrode thicknesses, and its concentration polarization decreases as the electrode thickness decreases, which is totally different from the channel-rib flow field. Moreover, a thinner cathode causes lower activation overpotential, whereas a thinner anode causes higher activation overpotential. In general, a thick anode, a thin cathode, and thin metal foam can maximize the current density of model D, while a thick electrode and metal foam can always reduce the temperature gradient. Finally, the Taguchi method and gray relational analysis are used to optimize the current density and temperature gradient of model D. The current density of an optimized model is 3.27% higher than that of the original model with a temperature gradient of 9.05 K/cm.

Effect of Mixed Morphology (Simple Cubic, Face-Centered Cubic, and Body-Centered Cubic)-Based Electrodes on the Electric Double Layer Capacitance of Supercapacitors.

Supercapacitors store energy due to the formation of an electric double layer (EDL) at the interface of the electrodes and electrolyte. The present article deals with the finite element study of equilibrium electric double layer capacitance (EDLC) in the mixed morphology electrodes comprising all three fundamental crystal structures, simple cubic (SC), body-centered cubic (BCC), and face-centered cubic morphologies (FCC). Mesoporous-activated carbon forms the electrode in the supercapacitor with (C2H5)4NBF4/propylene carbonate organic electrolyte. Electrochemical interference is clearly demonstrated in the supercapacitors with the formation of the potential bands, as in the case of interference theory due to the increasing packing factor. The effects of electrode thickness varying from a wide range of 50 nm to 0.04 mm on specific EDLC have been discussed in detail. The interfacial geometry of the unit cell in contact with the electrolyte is the most important parameter determining the properties of the EDL. The critical thickness of the electrodes is 1.71 μm in all the morphologies. Polarization increases the interfacial potential and leads to EDL formation. The Stern layer specific capacitance is 167.6 μF cm-2 in all the morphologies. The maximum capacitance is in the decreasing order of interfacial geometry, as FCC > BCC > SC, dependent on the packing factor. The minimum transmittance in all the morphologies is 98.35%, with the constant figure of merit at higher electrode thickness having applications in the chip interconnects. The transient analysis shows that the interfacial current decreases with increasing polarization in the EDL. The capacitance also decreases with the increase of the scan rate.

Influence of electrode characteristics on the laser cutting of lithium-ion battery anodes

Laser cutting of lithium-ion battery (LIB) electrodes is a highly flexible process receiving wider industry adoption. However, the manufacturing of LIB electrodes involves numerous steps, where variations can impact the electrode cutting process. Additionally, material chemistry is identified as one of the influential parameters affecting laser cutting. There are numerous combinations of state-of-the-art laser sources and anode materials. Conducting extensive examinations would be necessary to choose the optimized laser source for electrode cutting. On the other hand, understanding the influence of thickness and chemistry of anode materials on the processability is important. This study examines methodologically the characteristics of the anodes and their impact on laser cutting performance. The effects of electrode thickness and active material chemistry on the laser cutting performance using a ps-pulsed laser with burst mode capability were studied. Examinations were conducted on four various combinations of LIB anodes, encompassing four different thicknesses and two distinct chemistries.

A computational analysis of effects of electrode thickness on the energy density of lithium-ion batteries

Elevated energy density is a prime requirement for many lithium-ion battery (LIB) applications, including electric vehicles (EVs). At the cell level, the enhanced energy density of LIBs is achievable by designing thicker electrodes, which decreases the weight of the inactive materials. This work proposed a reduced order electrochemical model (ROEM), which is an extended single particle model (extended SPM), by incorporating the existing order reduction techniques of Pseudo-Two-Dimensional (P2D) model. The proposed model was used to predict the energy density values of a nickel cobalt manganese (NCM) cell with respect to the cathode thickness. The validation of the model was performed by using MATLAB at 0.05C, 1C, 2C, 3C and 5C rates by comparing the simulation results with the experimental data obtained from the Stanford Energy Control Laboratory. The verified model was then used to simulate the effect of varying thicknesses of the cathode on energy density of the NCM cell at C/5, C/2, 1C, and 2C rates of discharge. The simulation results illustrate that increasing the cathode thickness has a profound positive impact on the energy density of the cell. The prediction of the model demonstrates a total of around 20 % increase in energy density for the increment of cathode thickness from 75 μm to 600 μm. The proposed model can replicate energy density for thicker electrodes up to 2C rate reasonably correctly. However, the incorporation of thermal characteristics and other influential parameters of LIB cells into the proposed model can yield a better prediction of energy density of thicker electrodes at higher C-rates, which is recommended for further study.

Effect of simple cubic, face-centered cubic, and body-centered cubic-electrodes on the electric double layer capacitance of supercapacitors

The continuum theory has been used to analyze the polarization, ion crowding, and electrostatic forces of the electric double layer in the electrode materials having simple cubic (SC), body-centered cubic (BCC), and face-centered cubic (FCC) morphologies. The study manifests the effect of thickness of electrodes, electrode’s particle size, and porosity on electric double-layer specific capacitance (EDLC). Electrochemical interference and the specific capacitance depend on the packing factor. The larger particle size decreases the specific capacitance, but porosity increases due to more surface area. Due to symmetry, SC, BCC, and FCC morphologies have 1, 3, and 5 spheres in a unit cell. The number of unit cells is varied from 1 to 100 in model 1 to analyze the effect of electrode thickness. Model 2 has three unit cells to understand the effect of porosity, and only pore lengths are varied. The critical thickness of the electrodes is the integer multiples of 1.71 μm in all the morphologies. The Stern layer-specific capacitance is 167.6 μF cm−2 in all cases. The EDLC in BCC is around 5.6–7.6 μF cm−2 in the steady state that is intermediate between SC and FCC morphologies. The more dense packing of carbon particles in a unit cell increases the energy storage capabilities of electrodes. The average electrode permittivity slightly decreases due to the combined effect of the high electric field, status of polarization, and electrode particle size. The least optical transmission of electrodes is 98.35%.

A 3D modelling study on all vanadium redox flow battery at various operating temperatures

To understand whether the optimization of the operating/electrode structural parameters are temperature dependent, a 3D numerical model is developed and validated to gain insight into the impact of practical operating temperature (273.15 K–323.15 K) on vanadium redox flow battery (VRFB) performance, in which the property parameters are from published experimental data. The operating temperature is found significantly influence the optimal design of VRFBs. Increasing the inlet flow rate and state of charge (SOC), decreasing the electrode porosity and fibre diameter can all improve the battery performance with interdigitated flow channels, and the improvement increases with increasing temperature. In contrast, decreasing the fibre diameter or porosity increases the flow resistance and costs higher pump consumption, which is more pronounced at a lower temperature due to higher electrolyte viscosity. The effect of electrode thickness is also different at various temperatures. The gradient porosity electrode is applied in VRFB with interdigitated flow channels. The electrochemical performance of VRFB with gradient electrode (porosity increases from 0.8 at channel side to 0.93 at membrane side) performs similarly with the VRFB with 0.8 porosity electrode, while the pressure drop is reduced by 40% at all temperature. This model provides a deep understanding of effects of a wide range of working temperature on the optimization of operating/electrode parameters and on the VRFBs’ performance.

Study on aging and external short circuit mechanisms of Li-ion cells with different electrode thicknesses

Thermal runaway is one of the challenges associated with the widespread use of Li-ion batteries. The thermal runaway characteristics of Li-ion batteries are closely associated with the electrode materials, electrode structure design and degree of cycling deterioration. The energy density of Li-ion cells can be efficiently increased by expanding the electrode thickness, but cycle and thermal performance will be deteriorated with the increase of electrode thickness. The cycle performance and aging mechanisms of cells with different electrode thicknesses during cycling has been investigated in present research. Afterwards, the external short-circuit was conducted on aged cells to explore the effect of electrode thickness on cell thermal runaway behavior. The results showed that the ohmic internal resistance and polarization internal resistance of the thick-electrode cell increased continuously with cycling, and the capacity faded significantly. The increase in Li+ migration distance in a thick electrode will make the state of charge (SOC) distribution uneven along the thick direction. The thick electrode cell had the largest absolute temperature rise and temperature rise rate when it was short-circuited, which were 104.07 °C and 1.89 °C/s, respectively. The temperature of the area near the negative electrode of the cell was higher than that of the center and the positive electrode. The micro structure of electrode by SEM revealed that cycling can cause thick electrode material to crack, resulting in capacity loss. When thermal runaway developed, thick electrodes had the highest absolute temperature rise and temperature rise rate. As the current density increased, the thermal runaway would aggravate the damage to the positive electrode material, and the separator would close and shrink, thereby cutting off the reaction between the positive and negative electrodes.

Effect of aligned porous electrode thickness and pore size on bubble removal capability and hydrogen evolution reaction performance

Aligned porous electrodes with different pore sizes and thicknesses are prepared by freezing casting method, and the effect of the electrode thickness and pore size on hydrogen evolution reaction (HER) performance and bubble removal capability are experimentally studied. The results show that the pore size and thickness of the aligned porous electrodes have a significant impact on the HER performance by affecting the electrochemical active surface area (ECSA) and bubble transport process. The influence of pore sizes and electrode thicknesses on HER performance are different with current density. In the region of low current density, the effect of electrode thickness on electrochemical performance is more significant than that of pore size. While at high current density pore size becomes a limiting factor for electrochemical performance. Additionally, the Δζγ is proposed to evaluate the bubble removal capability, and a small Δζγ indicates the good bubble removal efficiency.

Analysis of polarization and thermal characteristics in lithium-ion battery with various electrode thicknesses

The increase in electrode thickness causes the higher energy density in the lithium-ion battery while the larger electric resistance and polarization will influence its thermal behaviors. Coupling electrochemical and thermal model is developed to study the effects of electrode thickness on polarization and thermal characteristics in lithium-ion battery, and to obtain specific values of polarization in positive and negative electrodes and discharge energy efficiency. The results reveal that the concentration polarization in solid matrix in positive and negative electrode will lead to larger drop amplitude in the terminal voltage curve in the initial stage and approaching to the end in discharging, respectively. With the increase in electrode thickness in discharging, the higher ratio of concentration polarization in liquid electrolyte to the total polarization occurs, and more ohmic heat than that of polarization happens, as well as the higher temperature and more non-uniformity temperature distribution take place in the battery under higher discharge rate, and the discharge energy efficiency drops with electrode. All results will help to optimize the electrode thickness in lithium-ion batteries to obtain better electrochemical-thermal performances.

Activated Carbon‐Based Supercapacitors with High Gravimetric and Volumetric Capacitance at Commercial‐Level Mass Loading

Activated carbons (ACs) are derived from cornhusk via a simple technique consisting of hydrothermal carbonization and following KOH activation, with porous structures and morphology of the ACs controlled by adjusting the amount of KOH for the activation. As the main active materials of the electrode for supercapacitors (SCs), both the porosity and morphology exhibit significant influence in the compaction density of the electrode. The ACs activated with a KOH/biochar ratio of 3:1 not only provide a high surface area of 3024 m2 g−1 but also guarantee a high compaction density of 11.6 mg cm−2 for a 200 μm‐thick electrode, leading to high performances for both gravimetric and volumetric capacitance. Moreover, the morphology of a thin sheet‐like interconnected network benefits the densely compact nature of the ACs in the electrode. Concerning the practical application, the effect of electrode thickness on the electrochemical performance is examined to optimize the electrode with commercial‐level mass loading with organic electrolyte, which is of ≈344 F g−1 in gravimetric capacitance and 210 F cm−3 in volumetric capacitance as well as excellent capacitance retention over 90% after 5000 galvanostatic charge–discharge cycles. In addition, good electrochemical performances of the optimized electrode with commercial‐level mass loading are over a broad range of work temperature.

The effect of electrode thickness and electrode/electrolyte interface on the capacitive deionization behavior of the Ti3C2Tx MXene electrodes

2D MXene sheets have been regarded as promising capacitive deionization (CDI) electrodes owing to their high conductivity, hydrophilic surface, excellent adsorption capacity, and reversible intercalation of metal cations. The 2D structure characteristic enables MXene sheets to provide massive spaces to catch Na+ and Cl- ions during the CDI process. In this work, the CDI behavior of Ti3C2Tx MXene has been comprehensively investigated by constructing a symmetrical device. The effect of electrode thickness and electrode/electrolyte on the CDI behavior of the Ti3C2Tx MXene electrodes is deeply investigated. The thin electrode could facilitate the electrolyte (NaCl solution) penetration in the electrode, provide more electrode/electrolyte interface contact, and shorten the ion diffusion pathway from the electrolyte to the internal electrode, leading to faster ion diffusion and better desalination capacity. The optimized MXene‖MXene CDI device with an electrode thickness of 18.41 µm exhibits a high salt removal capacity of 100.9 mg g−1 in NaCl solution at 1.2 V.

Au Wire Ball Welding and Its Reliability Test for High-Temperature Environment.

The long-term application of sensors in a high-temperature environment needs to address several challenges, such as stability at high temperatures for a long time, better wiring interconnection of sensors, and reliable and steady connection of the sensor and its external equipment. In order to systematically investigate the reliability of thin coatings at high temperatures for a long time, Au and Cr layers were deposited on silicon substrates by magnetron sputtering. Additionally, samples with different electrode thicknesses were annealed at different temperatures for a varied duration to study the effect of electrode thickness, temperature, and duration on the reliability of samples. The results of tensile and probe tests before and after heat treatment revealed that the mechanical strength and electrical properties have changed after annealing. In addition, the bonding interface was analyzed by a cross-sectional electron microscope. The analysis showed that long-term continuous high-temperature exposure would result in thinning of the electrode, formation of pores, recrystallization, and grain growth, all of which can affect the mechanical strength and electrical properties. In addition, it was observed that increasing the thickness of the gold layer will improve reliability, and the test results show that although the thin metal layer sample is in poor condition, it is still usable. The present study provides theoretical support for the application of thin coatings in high temperatures and harsh environments.

The Effect of Electrode Thickness on the High-Current Discharge and Long-Term Cycle Performance of a Lithium-Ion Battery

Six groups of electrodes with different thickness are prepared in the current study by using Li[Ni1/3Co1/3MN1/3]O2 as the active substance; the electrode thicknesses are 71.8, 65.4, 52.6, 39.3, 32.9, and 26.2 μm, respectively, with similar internal microstructures. The effect of electrode thickness on the discharge rate, pulse discharge, internal resistance, and long-term cycle life of a pouch cell are investigated. The results show that, with the decrease in the electrode thickness from 71.8 μm to 26.2 μm, the high-current-discharge performance of the cell gradually improves, the pulse-discharge power density under 50% SOC increases from 1561 W/Kg to 2691 W/Kg, the Rdis decreases from 8.70 mΩ to 3.34 mΩ, and the internal resistance decreases from 3.36 mΩ to 1.21 mΩ. In the long-term cycle-life test, the thinner the electrode thickness, the less the capacity fading of the cell; the internal resistance of the cell is observed with the increase in the cycle index.

Effect of Electrode Thickness on Quality Factor of Ring Electrode QCM Sensor.

As a key type of sensor, the quartz crystal microbalance (QCM) has been widely used in many research areas. Recently, the ring electrode QCM sensor (R-QCM) with more uniform mass sensitivity has been reported. However, the quality factor (Q-factor) of the R-QCM has still not been studied, especially regarding the effect of electrode thickness on the Q-factor. Considering that the Q-factor is one of crucial parameter to the QCM and it is closely related to the output frequency stability of the QCM, we study the effect of different electrode thicknesses on the Q-factor of the R-QCM in this paper. On the other hand, we clarify the relationship between the electrode thickness and the Q-factor of the R-QCM. The measurement results show that the average Q-factor increases with increases in the thickness of ring electrodes generally; however, the resonance frequency of the QCM resonator decreases with increases in the thickness. The low half-bandwidth (2Γ < 1630 Hz) of the R-QCM shows that the frequency performance is good. Additionally, the R-QCM has a higher Q-factor (Q > 6000), which indicates that it has a higher frequency stability and can be applied in many research areas.

Thickness‐dependent high‐performance solid oxide fuel cells with Ba0.5Sr0.5Co0.8Fe0.2O3‐δ cathode

AbstractThe electrochemical performance of solid oxide fuel cells (SOFCs) is highly reliant upon the properties of cathodes, including crystal structure, electrical conductivity, electrode thickness, and so on. Here, Ba0.5Sr0.5Co0.8Fe0.2O3‐δ (BSCF) is synthesized and served as the electrode for enabling high‐performance SOFCs. The effect of electrode thickness on the electrocatalytic activity is systematically investigated. The electrode thickness is adjusted in two ways. One is spray‐coating and then calcining once, and the other is performing the above process twice. On the basis of symmetrical cells configuration, the oxygen reduction reaction (ORR) activity of BSCF electrode with different thickness is evaluated and analyzed by the electrochemical impedance spectroscopy (EIS) technique and distribution of relaxation time (DRT). The obtained area‐specific resistances (ASRs) of electrodes on the oxygen ion conducting electrolyte Sm0.2Ce0.9O1.90 (SDC) demonstrate the thickness‐dependent electrochemical activity in ORR of BSCF electrode. With an electrode thickness of 24 μm that controlled by conducting “spray‐coating and calcining” twice, the BSCF electrode displays the optimal electrochemical performance with an ASR of 0.072 Ω cm2 in ambient air at 600°C. This strategy has allowed us to produce an electrode layer with optimal thickness, paving a new path for the design of high‐performance SOFCs.

Mo1.33CTz–Ti3C2Tz mixed MXene freestanding films for zinc-ion hybrid supercapacitors

The high demand on fast rechargeable batteries and supercapacitors combined with the limited resources of their active materials (e.g. Li and Co) motivate the exploration of sustainable energy storage systems such as Zn-ion hybrid supercapacitors. MXenes are two-dimensional materials with outstanding properties such as high conductivity and capacitance which enhance their performance in energy storage devices. Herein, we report on the use of freestanding Mo1.33CTz–Ti3C2Tz mixed MXene films in Zn-ion hybrid supercapacitors. The mixed MXene films are prepared from pristine MXene suspensions using a one-step vacuum filtration approach. The mixed MXene delivers capacities of about 159 and 59 mAh/g at scan rates of 0.5 and 100 mV/s, respectively. These capacity values are higher than the pristine MXene films and previously reported values for MXene electrodes in Zn-ion supercapacitors. Furthermore, the electrodes offer a promising capacity retention of about 90% after 8,000 cycles. In addition, the mixed MXene features energy densities of about 103 and 38 Wh/kg at power densities of 0.143 and 10.6 kW/kg, respectively. Insights into the effect of electrode thickness on rate performance and the mechanism of charge storage are also discussed. This study opens a venue for the use of Mo1.33CTz–Ti3C2Tz mixed MXene electrodes in sustainable energy storage systems with high energy density and power density.

Anode Material for Lithium-Ion Batteries Based on MoS2 and Conductive Polymer Binder: Effects of Electrode Thickness

Anode Material for Lithium-Ion Batteries Based on MoS2 and Conductive Polymer Binder: Effects of Electrode Thickness

En Route to a Unified Model for Photoelectrochemical Reactor Optimization. II–Geometric Optimization of Perforated Photoelectrodes

Results have been reported previously of a model describing the performance of photoelectrochemical reactors, which utilize semiconductor | liquid junctions. This model was developed and verified using SnIV-doped α-Fe2O3 as photoanodes. Hematite films were fully characterized to obtain parameter inputs to a model predicting photocurrent densities. Thus, measured photocurrents were described and validated by the model in terms of measurable quantities. The complete reactor model, developed in COMSOL Multiphysics, accounted for gas evolution and desorption in the system. Hydrogen fluxes, charge yields and gas collection efficiencies in a photoelectrochemical reactor were estimated, revealing a critical need for geometric optimization to minimize H2-O2 product recombination as well as undesirable spatial distributions of current densities and “overpotentials” across the electrodes. Herein, the model was implemented in a 3D geometry and validated using solid and perforated 0.1 × 0.1 m2 planar photoanodes in an up-scaled photoelectrochemical reactor of 2 dm3. The same model was then applied to a set of simulated electrode geometries and electrode configurations to identify the electrode design that would maximize current densities and H2 fluxes. The electrode geometry was modified by introducing circular perforations of different sizes, relative separations and arrangements into an otherwise solid planar sheet for the purpose of providing ionic shortcuts. We report the simulated effects of electrode thickness and the presence or absence of a membrane to separate oxygen and hydrogen gases. In a reactor incorporating a membrane and a photoanode at 1.51 V vs RHE and pH 13.6, an optimized hydrogen flux was predicted for a perforation geometry with a separation-to-diameter ratio of 4.5 ± 0.5; the optimal perforation diameter was 50 µm. For reactors without a membrane, this ratio was 6.5 and 8.5 for a photoanode in a “wired” (monopolar) and “wireless” (photo-bipolar) design, respectively. The results and methodologies presented here will serve as a framework to optimize composite photoelectrodes (semiconductor | membrane | electrolyte), and photoelectrochemical reactors in general, for the production of hydrogen (and oxygen) from water using solar energy.

Reliable Lab-Scale Evaluation of Solid Oxide Fuel Cells Electrode Performance – the Effect of Electrode Thickness and Current Collecting Spacing

Understanding and optimizing electrochemically active zone for oxygen reduction reaction in solidoxide fuel cells (SOFCs) cathodes are indispensable to maximize device’s performance. For mixed ionicand electronic conductors, the range of this zone depends on the oxygen surface exchange and solid-stateoxygen/electron transport properties of materials [1]. This aspect is also critical to realize validcharacterization of the electrode’s electrochemical activities. For instance, when a material’s electronicconductivity is low or the electrical contact points are spaced beyond a critical distance, the electrodepolarization resistance measured by electrochemical impedance spectroscopy will be controlled by the sheetresistance not the oxygen exchange resistance [2]. The situation becomes more complicated as the electricalconductivity of porous layer, which is an advantageous structure with large surface area and facile gas phasetransport, considerably deviates from the material’s intrinsic property. It is expected that porosity,connectivity, and impurity contents can have significant impact on porous electrode’s electronic conduction[3].In this context, we have studied effective in-plane electronic conductivity of lanthanum strontiumcobalt ferrite (LSCF) porous layers. The in-plane conductivity was measured by four-line probeconfiguration [4], modified from the widely used four-point probe technique to be applied for a porouslayer. We have confirmed that the in-plane electrical conductivity of screen-printed LSCF porous layers isone or two orders of magnitude lower than the material’s bulk property in ambient air, depending ontemperatures. This electronic conductivity deviation was taken into account to rationally designcombination of electrode thickness and current collector spacing and, in turn, to guarantee a validassessment of electrode performance. In addition, we found that electrical conductivity of LSCF porouslayers decreases by 20~30 %, within relatively short period of time (250~400 hours) upon repeated thermalcycles (500 ℃ to 700 ℃). Furthermore, we found that in-plane conductivity of thin (<10 µm) electrodes isstrongly dependent on the measurement time and the local atmospheric environment relative to thickerelectrodes. Special attention is required to use a thin electrode to evaluate electrode performance.This work was supported by the US Department of Energy (DOE), Office of Fossil Energy, (Officeof Clean Coal & Carbon Management), “Solid Oxide Fuel Cell Manufacturing in Support of Office ofFossil Energy” program through Argonne National Laboratory under FWP No. 27327.1.[1] S.B. Adler et al. J. Electrochem. Soc. 143 (1996) 3554-3564; S.B. Alder Solid State Ionics 111 (1998)125-134.[2] B.A. Boukamp et al. Solid State Ionics 192 (2011) 404-408; B.A. Boukamp et al. Solid State Ionics 283(2015) 81-90.[3] L. Holzer et al. J. Mater. Sci. 48 (2013) 2934-2952.[4] S.W. Peterson et al. J. Electrochem. Soc. 161 (2014) A2175-A2181.

From Fundamental Understanding to Engineering Design of High-Performance Thick Electrodes for Scalable Energy-Storage Systems.

The ever-growing needs for renewable energy demand the pursuit of batteries with higher energy/power output. A thick electrode design is considered as a promising solution for high-energy batteries due to the minimized inactive material ratio at the device level. Most of the current research focuses on pushing the electrode thickness to a maximum limit; however, very few of them thoroughly analyze the effect of electrode thickness on cell-level energy densities as well as the balance between energy and power density. Here, a realistic assessment of the combined effect of electrode thickness with other key design parameters is provided, such as active material fraction and electrode porosity, which affect the cell-level energy/power densities of lithium-LiNi0.6 Mn0.2 Co0.2 O2 (Li-NMC622) and lithium-sulfur (Li-S) cells as two model battery systems, is provided. Based on the state-of-the-art lithium batteries, key research targets are quantified to achieve 500Wh kg-1 /800Wh L-1 cell-level energy densities and strategies are elaborated to simultaneously enhance energy/power output. Furthermore, the remaining challenges are highlighted toward realizing scalable high-energy/power energy-storage systems.