Efficient Anode Research Articles

1T/2H Mixed-phase MoS2 with enlarged interlayer spacing induced via bacteria-derived carbon for long-lifespan pseudocapacitors

Pseudocapacitors (PCs) are considered prospective candidates for large-scale aqueous energy storage systems due to their high power density. However, the poor cycling stability resulting from sluggish metal ion transport kinetics and the instability of the electrode structure hinders their further applications. To address this issue, an effective strategy of 1T/2H mixed-phase MoS2 directly grown on the electrochemically activated carbon (EC) induced via bacteria-derived carbon (BC) from bacillus subtilis is proposed to achieve efficient anodes for potassium ion capacitors. The inherent nitrogen elements found in the bacteria-derived carbon, along with a trace amount of amines and their derivatives generated from amino acid decarboxylation, act as support by inserting into the MoS2 interlayer. Amines and their derivatives as intercalators could suppress the MoS2 layer stacking and mitigate structure damage, which is responsible for preventing rapid capacity fading. Thus, the mixed-phase MoS2 with an expanded interlayer spacing of 0.94 nm achieves a remarkable durability with a capacitance retention of 110.2 % after 40,000 cycles at 10 A g−1. Density Functional Theory (DFT) reveals that the mixed-phase MoS2 could improve electron transfer ability and cyclic stability, in which the rich vacancies introduced by bacteria-derived carbon could enhance the K+ adsorption. To highlight, the asymmetric capacitor device (ASC) adopting mixed-phase MoS2 anode shows a long lifespan (88 % capacitance retention over 10,000 cycles). This work will provide a green approach to boost cycling performance of MoS2 anodes and shed light on developing high-performance MoS2-based materials for electrochemical energy storage.

Constructing 3D Zincophilic Skeleton in Nitrogen-Doped Carbon Hybrid Fibers for Dendrite-Free Zn Anodes.

The Zn dendrite growth and side reactions are two major issues for the practical use of Zn metal anodes (ZMAs). Herein, an N-doped carbon-based hybrid fiber with the 3D porous skeleton and the zincophilic Cu nanoparticles (denoted as Cu@HLCF) is developed for stable ZMAs. The zincophilic Cu particles in the skeleton work as the active sites to facilitate uniform Zn nucleation. Meanwhile, the abundant pores in the framework of the hybrid fibers provide a large space to relieve the structural stress and suppress the dendrite growth. Moreover, the good mechanical characteristics of the hybrid fiber ensure its high potential applications for flexible electronics. Theoretical analysis results disclose the strong interaction between Zn and Cu sites, and experimental results demonstrate the low voltage hysteresis, high reversibility, and dendrite-free behavior of the Cu@HLCF host for Zn plating/stripping. Moreover, the solid-state Zn-ion battery (ZIB) assembled with a Cu@HLCF/Zn anode shows the prominent flexibility, impressively reliability, and outstanding cycling capability. Therefore, this work not only provides a novel design for the efficient and stable Zn metal anode but also promotes the development of flexible power sources for flexible electronics.

Co@CoO core–shell cross-linked framework modified 3D Cu for dendrite-free lithium anode

Lithium metal anode with high energy density is important for developing next-generation batteries. However, low coulombic efficiency, short cycle life, internal short circuits caused by the growth of lithium dendrites, and the high reactivity with the electrolyte have seriously hindered the practical application of lithium metal anode. Herein, we constructed a core–shell cross-link matrix on copper, Co@CoO/3D Cu, for Li metal anode optimization. Various characterizations and DFT simulations jointly reveal the great effects of the special structural features of Co@CoO/3D Cu on enhancing the coulombic efficiency and cyclic stability of Li metal anodes. As a result, the modified half-cell could cycle stably for 240 cycles at 1 mA cm−2 and 1 mA h cm−2 with a coulombic efficiency as high as 98 %. The modified symmetric cell could cycle stably for 1400 h at 1 mA cm−2 and 1 mA h cm−2 with a very low polarization of 22 mV. The modification method proposed in this paper provides a novel path for Li metal anode optimizations.

Boosting the initial coulombic efficiency for SiO anodes through component controlling and microcrystalline size limiting regulated by carbon layer

Silicon-based anode materials are attracting considerable attention due to their high specific capacity for further improving the energy density of lithium-ion batteries (LIBs). Among them, silicon monoxide (SiO) has a good balance between high specific capacity and cycling lifespan, which is increasingly valuable in the market of lithium-ion batteries. However, its poor initial coulombic efficiency (ICE) severely impedes the commercialization of SiO. Although prelithiation and surface carbon coating are considered effective methods to reduce irreversible consumption during the initial lithiation process, the synergistic relationship between prelithiation and carbon coating has not yet been confirmed. Herein, we used LiH as solid-phase prelithiation reagent and acetylene as carbon source for carbon coating to improve the ICE as well as cyclic stability of SiO anode. Results show that the process sequence of pre-lithiation and carbon coating has a significant impact on regulating the internal lithium silicate components and the microcrystalline size of silicon and lithium silicates. A prioritizing carbon layer coating subsequent to prelithiation can achieve physical barrier effect, effectively regulating the prelithiation reaction process to refine the internal silicon and lithium silicate crystal material, and avoiding the formation of lithium-poor Li2Si2O5 phase. The obtained SOC-P sample exhibits a superior ICE of 88.1 % and a stable irreversible capacity of 842.9 mAh/g after 200 cycles. This work provides practical reference idea for solving the low initial efficiency issue of SiO anode material.

Enhancing primary aqueous magnesium-air battery performance by tailoring anode texture

The mechanisms of the texture generated during the rolling process on the anodes of magnesium-air batteries remain unclear. This work systematically investigates the impact of texture on the dissolution and discharge processes of magnesium anodes using theoretical calculations combined with experiments. Results demonstrate that the ND (Normal Direction) plane of the rolled sheet contained a higher proportion of (0001) oriented grains, exhibiting excellent stability, the slowest anodic dissolution rate, superior corrosion resistance, and enhanced discharge performance. At a current density of 40 mA·cm−2, the discharge capacity and anode efficiency of the ND plane reached impressive values of 1369.86 mAh·g−1 and 61.57%. Additionally, hydrogen evolution, chunk effect, and loss of discharge during the discharge process of AZ31 anodes were quantified for the first time. Furthermore, the effect of texture on the cracking of the discharge product layer was investigated.

Life cycle assessment of lithium-sulfur batteries with carbon nanotube hosts: Insights from lab experiments

Lithium‑sulfur (Li-S) batteries are candidates for next-generation batteries. It can be produced sustainably using sulfur instead of controversial cathode minerals like cobalt. However, Li-S batteries must improve their energy density and cycle life at their current state of development. Hosting the sulfur on carbon nanotubes (CNT) is a potential solution. This study investigated the environmental performance of a CNT-based Li-S battery based on original experiment data. The CNT in the batteries functioned as binders, conductive fillers, and current collectors, reducing auxiliary materials and simplifying manufacturing processes. We conducted a cradle-to-gate life cycle assessment (LCA) to clarify the environmental performance. We showed that the global warming potential (GWP) of the Li-S battery pack in a conventional battery structure was 105 kg CO2e/kWh. By partially substituting current collectors, increasing lithium anode efficiency, and reducing solvent usage, we could achieve 87, 82, and 78 kg CO2e, respectively. The lowest GWP of Li-S battery was 20 % lower when compared to a graphite‑nickel manganese cobalt oxides (NMC) battery. In addition, the other environmental indicators, including human toxicity, ecotoxicity, and acidification, were 26 % to 79 % lower, showing no major environmental burden shift. One exception was the mineral resource depletion, which was 2 % higher because lithium metal, instead of synthetic graphite, was used as a high-capacity anode pair. This study also found that modifying the cathode production process by using a less energy-intensive filtration before evaporating the remaining solvent could significantly reduce the energy required, thus mitigating the previously identified environmental hotspot. Our finding highlighted that a prospective LCA collaborating with battery experimentalists could lead to novel discoveries for environmentally sustainable battery production. Overall, we showed that Li-S batteries are environmentally preferred at the production stage, as supported by advanced experiments. Further research into improving the cycle life of Li-S batteries is crucial when considering the use stage to reduce the environmental impact per functional unit of energy delivered over the battery lifetime.

Efficient Chemical Prelithiation with Modificatory Li+ Solvation Structure Enabling Spatially Homogeneous SEI toward High Performance SiOx Anode†

Comprehensive SummaryChemical prelithiation is widely proven to be an effective strategy to address the low initial coulombic efficiency (ICE) of promising SiOx anode. Though the reagent composition has been widely explored, the Li+ solvation structure, which practically plays the cornerstone role in the prelithiation ability, rate, uniformility, has rarely been explored. A novel environmentally‐friendly reagent with weak solvent cyclopentyl methyl ether (CPME) is proposed that enables both improved ICE and spatial homogeneous solid electrolyte interphase (SEI). And the prelithiation behavior and mechanism were explored focused on the Li+ solvation structure. Both theoretical investigation and spectroscopic results suggest that weak solvent feature of CPME reduces the solvent coordination number and decreases the Li+ desolvation energy. The optimized Li+ solvation structure enables high‐efficiency prelithiation that ensures the horizontal homogenization and mechanical properties of SEI. Moreover, the accompanied CPME molecules preferentially occupy positions in initial SEI, reducing the likelihood of LiPF6 decomposition and promoting longitudinal homogenization of SEI. Consequently, the efficient and homogenous prelithiation enables impressive ICE of 109.52% and improved cycling performance with 80.77% retained after 300 cycles via just 5 min soaking. Furthermore, the full cells with LiNi0.83Co0.12Mn0.05O2 (NCM831205) cathode display an enhancement in the energy density of 179.74% and up to 648.35 Wh·kg–1.

Synergy of Weakly Solvated Electrolyte and LiF-Reinforced Interphase Enables Long-Term Operation of Li-Metal Batteries at Low Temperatures.

Hindered by the high diffusion energy barrier of Li+ in graphite anode layers, the low-temperature application of traditional Li-ion batteries is limited. Lithium metal without intercalation and with excellent specific capacity is expected to support battery operation at low temperatures. However, due to the low conductivity, high freezing point, and strong solvation energy of traditional carbonate electrolytes, the application of lithium-metal batteries at low temperatures remains challenged. In this paper, an all-ester-based ternary solvent electrolyte based on fluorinated carbonate and methyl acetate is developed to improve the cyclic efficiency of the Li-metal anode at subzero temperatures. Methyl acetate, with low viscosity and low freezing point, endows Li+ with efficient transfer in the bulk phase at low temperatures. Fluorinated cosolvent regulates the solvation structure, thereby facilitating Li+ desolvation while forming a LiF-rich solid electrolyte interphase. The electrolyte exhibits good compatibility with the Li-metal anode, as confirmed by the significantly reduced kinetic barrier of Li+ diffusion at the interface. The theoretical calculations suggest that anions occupy the dominant positions within the inner solvation sheath. The in situ/ex situ characterizations provide straightforward evidence of a dendrite-free Li-metal electrode during cycling. As a result, the symmetric Li||Li cell is able to cycle stably for thousands of hours at current densities of 0.5 mA cm-2 and 1 mAh cm-2. When paired with a LiFePO4 cathode, the battery at 0.2 C (1 C = 170 mA g-1) has a capacity retention of 95.4% after 200 cycles at -15 °C and 92.6% after 100 cycles at -20 °C, respectively.

Bimetallic metal-organic frameworks -derived lithiophilic and conductive MnO/Co/C enabled intermittent deposition model for high-performance lithium metal anode

The design of lithiophilic three-dimensional (3D) skeletons has proven to be effective in inhibiting dendrite growth and improving the Coulombic efficiency of lithium metal anodes (LMAs). However, for the 3D skeletons with homogenous lithiophilicity, Li would preferentially deposit on the top of 3D collectors, what's more, the intrinsic low electrical conductivity of metal-organic frameworks (MOFs)-derived oxides which are often employed as the lithiophilic materials on 3D skeletons affects their electrochemical kinetics. We firstly prepare MnO/Co/C derived from MnCo-MOFs on carbon cloths (CC) by a simple method and a composite anode (Li-CC@MnO/Co/C) is obtained. The synergistic effect of the electrical conductivity of Co and lithiophilicity of MnO facilitates their electrochemical kinetics. The Li-CC@MnO/Co/C composite anode exhibites long cycle life and low hysteretic voltage in the symmetrical cell with a high areal capacity and current density (5 mA h cm−2, 5 mA cm−2) and a steady cycle performance of 80 mA h g−1 at 10 C for nearly 300 cycles in easter-based electrolyte. This work might propose a rational design for a high-performance LMA, particularly suitable for practical applications.

High-Current Density Performance of a Magnetically Shielded Hall Thruster

The performance of a magnetically shielded Hall thruster operating on xenon and krypton is characterized at discharge current densities up to 10 times greater than its nominal level. A thrust stand and far-field probe suite are employed to evaluate operation at 300 V discharge voltage and discharge currents from 15 to 125 A (xenon) and from 15 to 150 A (krypton). The thrust, specific impulse, and anode efficiency at the highest currents are found to be 1650±30 mN, 2309±56 s, and 52.8±2.0% respectively for xenon, and 1839±18 mN, 2567±48 s, and 55.0±1.6% for krypton. The thrust density at the highest conditions are shown to be six (xenon) and eight (krypton) times higher than the lowest current condition. A maximum in anode efficiency as a function of discharge current is observed for both gases. This is attributed to a trade between mass utilization, which increases to unity with current, and beam utilization, which gradually decreases with current. The dependence of these efficiency modes on current is discussed in the context of a series of first-principles scaling laws. The observation that efficiency only moderately decreases with current density is examined in the context of high-power electric propulsion development.

Biochar-Derived Anode Materials for Lithium-Ion Batteries: A Review

Highly portable nanoelectronics and large-scale electronics rely on lithium-ion batteries (LIBs) as the most reliable energy storage technology. This method is thought to be both environmentally friendly and cost-effective. We provide a study of a low-cost, abundant, and renewable supply of carbon-based biomass with potential uses in LIBs. Renewable feedstocks have received significant attention in recent decades as promising tools for efficient and alternative anode materials for LIBs. Researchers can synthesise carbon-rich biochar through the pyrolytic process of biomass. Depending on the synthetic process, precise surface chemistry, and textural qualities such as specific surface area and porosity, this material can be customised to favour application-specific properties with a preferred application. In this research, we look at the performance of biochar in LIBs, its properties, and the biomass supply, and we discuss the prospects for these biomass-derived materials in energy storage devices.

Nanomesh NiO-modified carbon cloth for highly efficient self-supporting potassium metal anodes

Potassium metal is one of the most promising anode materials for potassium-ion batteries owing to its low cost and ability to withstand high current density and relatively low operating potential. However, it is restricted from being used in practical implementations because of its high reactivity and disordered dendrite growth. To circumvent these issues, we stabilize potassium metal anodes by growing NiO with high potassium affinity and interconnected network porous structure on carbon cloth fibers (CC-NiO). A symmetric cell assembled from a composite material formed by infiltrating molten K into CC-NiO (K@CC-NiO) can cycle stably for 1840 h at a low overpotential of 33 mV. Furthermore, the first-cycle discharge capacities of the full batteries with carbon nanotubes-interwoven KFeSO4F microspheres (KFSF@CNTs) and perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) as the cathodes are 101.4 and 105.1 mAh g−1, respectively. The capacity retention of KFSF@CNTs||K@CC-NiO full battery after 1000 cycles is 79.3 %, and the capacity retention of PTCDA||K@CC-NiO full battery after 800 cycles is 70.2 %. The strategy of utilizing NiO as an efficient potassium metal nucleation anchor opens up a new direction for the development of high-energy and long-cycle-life potassium metal batteries.

The efficacy of ammonium ionic liquid to inhibit the parasitic process for Al-air battery

The main objective of this study is to determine how effectively the ammonium ionic liquid (tris(2 hydroxyethyl) methyl ammonium methylsulfate [THMA]+[MS]− works in minimizing parasitic reactions during Al-air battery discharge. The findings obtained indicate that the use of [THMA]+[MS]− reduced the rate of hydrogen gas output during the immersion of Al substrate in the 4.0 M KOH solution. The effectiveness of the ammonium ionic liquid under comparable conditions is confirmed using the linear cathodic polarization method. The addition of [THMA]+[MS]− to a pure 4.0 KOH solution improved the anodic efficiency and capacity density of the battery. Aside from being a novel study for [THMA]+[MS]− as electrolyte battery additives, theoretical research were employed to analyze the mechanism and data interpretation. Molecular dynamics (MD) simulations of inhibitor-Al interactions performed with Forcite's Materials Studio module add to the data that ammonium ionic [THMA]+[MS]− may suppress the parasite process. SEM, EDX, and X-ray Photoelectron Spectrometer (XPS) tests for Al electrodes under different circumstances following battery discharge at 20 mA cm−2 support the performance of [THMA]+[MS]−.

Investigation of hexagonal boron nitride monolayer with pores as an anode material for sodium-ion batteries

The hexagonal boron nitride monolayer (h-BNML) used as an anode material for metal-ion batteries was assumed pristine form. However, inspired by the imperfections in natural materials, this study investigates the effect of defects on the electrochemical properties of h-BNML. Within the current piece of research, h-BNML with pores is introduced to develop an anode material for sodium ion battery (SIBs) by undertaking density-functional theory (DFT) computations. During the diffusion and storage process of Na ions, the pores effect was thoroughly investigated. The boron atoms were removed from the structure of the pure h-BNML in order to form the h-BNML with pores, which mimicked the pore formation. Based on the DFT results, after the pore formation, the h-BNML retained its planarity. Following the introduction of vacancies, significant alterations occurred in the electronic structure characteristics of h-BNML within the pores, facilitating the effective adsorption of Na ions within the pore. The results of quantum theory of atoms in molecules indicated that there were interactions between the pores and Na ions through an electrostatic-type attraction. The h-BNML with pores was capable of retaining a large number of Na ions at its surface without any change in its planar structure. This led to an increase in its theoretical specific capacity, which increased with porosity. Hence, unlike the pure h-BNML, the pore formation improved the diffusion of Na ions. This can be promising to designing highly efficient anodes for SIBs. The methodological approach in this study can be used for tailoring porous BN materials for SIBs.

Characterization of the aluminium-air battery utilizing a polypropylene separator with corrosion inhibition ability

Battery energy storage systems are widely used in modern electronic devices and electric vehicles. Metal-air batteries are among the electrochemical energy storage systems that provide high energy density and eco-friendly solutions. Aluminium-air batteries hold a significant advantage with their high theoretical specific energy and have the potential to replace lithium-ion batteries in the future. In this study, the electrical performance and corrosion inhibition characteristics of a polypropylene-based single and dual electrolyte system for aluminium-air batteries were investigated experimentally. The study revealed that a polypropylene separator can reduce the corrosion of the aqueous aluminium-air battery system by up to 40 %, improving the anodic utilization efficiency to 93 %. Electrochemical impedance spectroscopy analysis was used to characterize the single and dual electrolyte aluminium-air battery and propose equivalent circuit models. Compared to 1 M KOH electrolyte in a single electrolyte system, the solution resistance of a dual electrolyte aluminium-air battery was reduced by about 40 % using a combination of 1 M of KOH electrolyte and 1 M of H2SO4. This reduction is attributed to the enhancement of the oxygen reduction reaction at the air cathode. A high KOH electrolyte concentration will increase the corrosion of the aluminium anode but can improve the battery’s voltage. At 3 M KOH electrolyte, the plateau voltage is recorded at about 0.6 V while the discharge time reached 44 min when using aluminium alloy 6061 as the anode. The battery model developed in this work provides a fundamental basis for predicting the performance of aluminium-air battery packs.

The semi-continuous (Mg,Al)2Ca second phase on Mg-Al-Ca-Mn alloys as an efficient anti-corrosion anode for Mg-air batteries

Developing high anti-corrosion and good discharge properties of magnesium based alloys for Mg-air batteries is still in challenge. In this work, a series of Mg-Al-Ca-Mn (AMX) alloys are prepared, and the second phases on AMX alloys are adjusting by varying the Al content. The AMX alloys with 3 wt% Al (denoted as AMX311) exhibits the excellent anti-corrosion behavior with a corrosion current density of 85.7 μA cm−2 and a low corrosion rate (4.1±0.21 mm y−1) in the 3.5 wt% NaCl solution. Furthermore, AMX311 shows lower hydrogen evolution volume (20.9±1 ml/cm2) and weight loss (5.8±0.3 mg) compared to other contrast samples. The outstanding electrochemical corrosion performance of AMX311 is attributed to the Al-rich oxide film which slowing corrosion at the initial stage and the formation of semi-continuous (Mg,Al)2Ca phase which can acts as a physical barrier to prevent the electrolyte from further corroding the magnesium matrix. Moreover, the AMX311 exhibits the highest discharge voltage (-1.471 V) and a peak specific energy of 1684.7±30.0 mW h g−1 at 20 mA/cm2, due to its superior corrosion resistance and reduced chunk effect. This work provides a good guide for designing advanced Mg-based alloys and an excellent insight into the effect of second phase on the corrosion and discharge performance of Mg-air batteries anode materials.

Rationally designed capacitive enhanced three-dimensionally feather-like Co3O4/ZnCo2O4/NF composite as efficient anode for lithium-ion batteries

Rationally designed capacitive enhanced three-dimensionally feather-like Co3O4/ZnCo2O4/NF composite as efficient anode for lithium-ion batteries

Electrodeposition of Tin and Antimony-Based Anode Materials for Sodium-Ion Batteries

Tin antimonide (SnSb) is a promising alloying anode for sodium-ion batteries due to its high theoretical capacity and relative stability. The material is popular in the battery field, but, to our knowledge, few studies have been conducted on the influence of altering Sn and Sb stoichiometry on anode capacity retention and efficiency over time. Here, Sn-Sb electrodes were synthesized with compositional control by optimizing electrodeposition parameters and stoichiometry in solution and the alloys were cycled in sodium-ion half-cells to investigate the effects of stoichiometry on both performance and electrochemical phenomena. Higher concentrations of antimony deposited into the films were found to best maintain specific capacity over 270 cycles in the tin-antimony alloys, with each cell showing a slow, gradual decrease in capacity. We identified that a 1:3 ratio of Sn:Sb retained a specific capacity of 486 mAh g−1 after 270 cycles, highlighting a need to explore this material further. These results demonstrate how control over stoichiometry in Sn-Sb electrodes is a viable method for tuning performance.

GradientFunctionalLayerAnodeforCarbonate-SuperstructuredSolidFuelCellswithEthaneFuel.

Carbonate-superstructured solid fuel cells (CSSFCs) are an emerging type of fuel cells with high flexibility of fuels. However, using ethane fuel for solid fuel cells is a great challenge due to serious degradation of their anodes. Herein, this critical issue is solved by creating a novel gradient functional layer anode for CSSFCs. First, a finer-scale anode with a larger surface area is demonstrated to provide more active sites for the internal reforming reaction of ethane, achieving a 60% higher ethane conversion rate and 40% lower polarization resistance than conventional anodes. Second, incorporating a gradient functional layer into the anode results in an additional 50% enhancement in the peak power density of CSSFCs to a record high value (up to 241mW cm-2) with dry ethane fuel at a low temperature of 550°C, which is even comparable to the power density of conventional solid oxide fuel cellsabove 700°C. Furthermore, the CSSFC with the gradient anode exhibits excellent durability for over 200 h. This finding provides a new strategy to develop efficient anodes for hydrocarbon fuels.

Experimental demonstration of a water electrolysis Hall Effect Thruster (WET-HET) operating with a hydrogen cathode

This study presents the first experimental demonstration of a Hall Effect Thruster operating with water electrolysis-derived constituents: oxygen for the anode (thruster) and hydrogen for the cathode, both from pressurised bottles. In contrast to prior research where the thruster was operated with oxygen to the anode and xenon/krypton to the cathode, this investigation uses an advanced set-up that safely allowed the combined use of pressurised oxygen and hydrogen. Firstly, a comparative assessment between the established plasma filament cathode (utilised in previous research) and a novel LaB6 cathode (referred to as Hydrocat), both krypton-fuelled, is conducted. Results show a different IV curve for these cathodes, but negligible disparities in thruster performance for fixed discharge power and anode mass flow. Thrust, anode specific impulse, thrust-to-power ratio, and both, anode and total efficiency of the system using oxygen (anode) and hydrogen (cathode) are then presented and compared against oxygen (anode) and krypton (cathode). The cathode successfully operated on hydrogen, with a reduction in thrust performance of under 10% compared to when krypton is used as the cathode propellant. This performance difference can be attributed to different factors, such as the reduced efficiency of the cathode running with hydrogen due to a higher ionisation potential and the cathode propellant’s contribution to thrust, more significant when using heavier propellants such as xenon/krypton compared to hydrogen. The impact of changing the hydrogen-to-oxygen ratio is also assessed and shown to have no impact on the thruster’s performance. The most optimal performance was obtained at the highest discharge power tested (Pd=1953±1 W), using a hydrogen:oxygen ratio of Φ = 1:25. This operating point corresponded to a thrust of 20.9±0.2 mN, anode specific impulse of 2130±20 s, thrust-to-power ratio of 10.7±0.5 mN/kW, anode thrust efficiency of 11.2±0.3 %, and total efficiency of 10.1±0.3 %.