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At least 1,567 records · Page 87
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

K{sub 1.33}Mn{sub 8}O{sub 16} as an electrocatalyst and a cathode

Density functional theory (DFT) calculations are carried out to investigate the electronic, magnetic and thermoelectric properties of bulk and nanosheet K{sub 1.33}Mn{sub 8}O{sub 16} materials. The catalytic activity and cathodic performance of bulk and nanosheet structures are examined using the Tran-Blaha modified Becke-Johnson (TB-mBJ) exchange potential. Electronic structure calculations reveal an anti-ferromagnetic ground state, with a TB-mMBJ band gap in bulk K{sub 1.33}Mn{sub 8}O{sub 16} that is in agreement with experimental results. Density of state plots indicate a partial reduction of Mn{sup 4+} ions to Mn{sup 3+}, without any obvious sign of Jahn-Teller distortion. Moreover, use of the O p-band center as a descriptor of catalytic activity suggests that the nanosheet has enhanced catalytic activity compared to the bulk structure. Thermoelectric parameters such as the Seebeck coefficient, electrical conductivity, and thermal conductivity are also calculated, and it is found that the Seebeck coefficients decrease with increasing temperature. High Seebeck coefficients for both spin-up and spin-down states are found in the nanosheet relative to their value in the bulk K{sub 1.33}Mn{sub 8}O{sub 16} structure, whereas the electrical and thermal conductivity are reduced relative to the bulk. In addition, figures of merit values are calculated as a function of the chemical potential and it is found that the nanosheet has a figure of merit of ~1 at room temperature, compared to 0.5 for the bulk material. All results suggest that K{sub 1.33}Mn{sub 8}O{sub 16} nanosheets can be used both as a material in waste heat recovery and as an electrocatalyst in fuel cells and batteries. - Graphical abstract: K{sub 1.33}Mn{sub 8}O{sub 16}: bulk and nanosheet. - Highlights: • Electronic properties of bulk and nanosheet forms of K{sub 1.33}Mn{sub 8}O{sub 16} have been studied. • The K{sub 1.33}Mn{sub 8}O{sub 16} nanosheet is a semiconductor while the bulk is a metal. • K{sub 1.33}Mn{sub 8}O{sub 16} Nanosheet is a more efficient electrocatalyst than bulk K{sub 1.33}Mn{sub 8}O{sub 16}. • High figure of merit of K{sub 1.33}Mn{sub 8}O{sub 16} nanosheet makes it an efficient cathode.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Improving the cycle stability of LiCoPO{sub 4} nanocomposites as 4.8 V cathode: Stepwise or synchronous surface coating and Mn substitution

Nanostructured LiCo{sub 1−x}Mn{sub x}PO{sub 4}/C (x = 0 and 0.05) materials were successfully produced as superior quality cathodes by combined sol-gel and carbothermal reduction methods. X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), energy dispersive spectroscopy (EDS), fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), cyclic voltammetry (CV) and galvanostatic measurements were applied to determine the phase purity, morphology and electrochemical qualifications. HR-TEM analysis reveals that the thickness of the surface carbon layer of 5 to 10 nm range with the uniform distribution. LiCo{sub 0·95}Mn{sub 0·05}PO{sub 4}/C particles were between 40 and 80 nm and the same material exhibits a higher and stable reversible capacity (140 mA h g{sup −1}) with the long voltage plateau (4.76 V). Substitution of Co{sup 2+} with Mn{sup 2+} in LiCoPO{sub 4}/C has an influence on the initial discharge capacity and excellent cycling behaviour. The obtained results have attributed that production dynamics in nano-synthesis, the coating process with proper carbon source and an effective doping represent three parameters to prepare favorable cathode materials. - Highlights: • Structural, morphological and electrochemical effects of Mn doped LiCo{sub 1−x}Mn{sub x}PO{sub 4}–C electrodes are investigated. • Cheap, effective and simple sol-gel assisted carbothermal reduction approach is used. • After 60th cycle, capacity retention is almost 92% for LiCo{sub 0·95}Mn{sub 0.05}PO{sub 4}–C electrode. • Mn-doped sample exhibits distinctive oxidation (4.76 V and 4.12 V) peaks.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Synthesis and characterization of novel Ce{sub 0.8}Sm{sub 0.2}Fe{sub 0.9}Ir{sub 0.03}Co{sub 0.07}O{sub 3−δ} perovskite material and possible application as a cathode for low–intermediate temperature SOFCs

Highlights: • Ce{sub 0.8}Sm{sub 0.2}Fe{sub 0.9}Ir{sub 0.03}Co{sub 0.07}O{sub 3−δ} was synthesized using sol–gel methods. • Material was thoroughly characterized using Raman, FTIR, XRD, HRTEM, SEM, and TGA. • Electrochemical performance showed the materials are a promising new cathode material for low temperature SOFC. - Abstract: A novel perovskite material, Ce{sub 0.8}Sm{sub 0.2}Fe{sub 0.9}Ir{sub 0.03}Co{sub 0.07}O{sub 3−δ} was synthesized using a sol–gel technique. The materials were calcined at temperatures of 800 °C, 900 °C, and 1000 °C and then characterized using X-ray diffraction, Raman and infrared spectroscopy, high resolution transmission electron microscopy and scanning electron microscopy (SEM). The particle sizes and crystallite sizes increased with increasing calcination temperature and formed perovskite type materials with some separate magnetite and iridium oxide. The powders were used to assemble button cells using samarium doped ceria as the electrolyte and NiO/SDC as the anode materials. The electrochemical properties were investigated using a Fiaxell open flanges test set-up and a Nuvant™ Powerstat-05 potentiostat/galvanostat. The Ce{sub 0.8}Sm{sub 0.2}Fe{sub 0.9}Ir{sub 0.03}Co{sub 0.07}O{sub 3−δ} cathode material calcined at 1000 °C exhibited the most promising performance, with a maximum power density of 0.400 W/cm{sup 2}, a current density of 0.8 A/cm{sup 2}, and a corresponding area specific resistance of 0.247 Ωcm{sup 2} at 500 °C. The button cells were reasonably stable over15 h.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Synthesis, characterization and rate capability performance of the micro-porous MnO{sub 2} nanowires as cathode material in lithium batteries

Graphical abstract: Translating MnO{sub 2} nanowires as cathode materials in coin cell and studying their discharge behavior and cycling stability at different C-rates. - Highlights: • MnO{sub 2} nanowires have been synthesized via hydrothermal route. • The nanowires were employed as cathode materials in Li-batteries. • Discharge and cycling stability were studied at different C-rates. • Specific capacity and power density of 251 mAh g{sup −1} and 200 W kg{sup −1} were attained. - Abstract: A peculiar architecture of one-dimensional MnO{sub 2} nanowires was synthesized by an optimized hydrothermal route and has been lucratively exploited to fabricate highly efficient microporous electrode overlays for lithium batteries. These fabricated electrodes comprised of interconnected nanoscale units with wire-shaped profile which exhibits high aspect ratio in the order of 10{sup 2}. Their outstanding intercalation/de-intercalation prerogatives have also been studied to fabricate lithium coin cells which revealed a significant specific capacity and power density of 251 mAh g{sup −1} and 200 W kg{sup −1}, respectively. A detailed electrochemical study was performed to elucidate how surface morphology and redox reaction behaviors underlying these electrodes influence the cyclic behavior of the electrode. Rate capability tests at different C-rates were performed to evaluate the capacity and cycling performance of these coin cells.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Effect of solvents on the electrochemical properties of binder-free sulfur cathode films in lithium–sulfur batteries

Highlights: • The binder-free sulfur electrode with high sulfur contents of 75 wt.% was fabricated. • The binder-free sulfur electrode using NMP solvents showed 784 mAh g{sup −1} after 40 cycles. • The solvent affect the electrochemical properties of binder-free sulfur electrode films. - Abstract: The effects of solvents on the preparation of sulfur cathodes were investigated by fabricating binder-free sulfur electrode films using three different solvents: 1-methyl-2-pyrrolidinone (NMP), acetonitrile, and deionized water. These solvents are commonly employed to dissolve binders used to prepare sulfur cathodes for lithium–sulfur batteries. The sulfur electrode fabricated with NMP had a higher discharge capacity and longer cycle life than the ones fabricated with acetonitrile and deionized water. Better adhesion between the current collector and the sulfur electrode accounted for the improved capacity and cycle life of the battery. In addition, the stability of the electrode in the electrolyte was a result of the solubility of sulfur in the solvent. We thus concluded that the solvents used in the fabrication of sulfur electrodes had a positive influence on the electrochemical properties of Li–S batteries.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Scalable and template-free synthesis of nanostructured Na{sub 1.08}V{sub 6}O{sub 15} as high-performance cathode material for lithium-ion batteries

Highlights: • Nanostructured Na{sub 1.08}V{sub 6}O{sub 15} was synthesized through additive-free sol-gel process. • Prepared Na{sub 1.08}V{sub 6}O{sub 15} demonstrated high capacity and sufficient cycling stability. • The reaction temperature was optimized to allow scalable Na{sub 1.08}V{sub 6}O{sub 15} fabrication. - Abstract: Developing high-capacity cathode material with feasibility and scalability is still challenging for lithium-ion batteries (LIBs). In this study, a high-capacity ternary sodium vanadate compound, nanostructured NaV{sub 6}O{sub 15}, was template-free synthesized through sol-gel process with high producing efficiency. The as-prepared sample was systematically post-treated at different temperature and the post-annealing temperature was found to determine the cycling stability and capacity of NaV{sub 6}O{sub 15}. The well-crystallized one exhibited good electrochemical performance with a high specific capacity of 302 mAh g{sup −1} when cycled at current density of 0.03 mA g{sup −1}. Its relatively long-term cycling stability was characterized by the cell performance under the current density of 1 A g{sup −1}, delivering a reversible capacity of 118 mAh g{sup −1} after 300 cycles with 79% capacity retention and nearly 100% coulombic efficiency: all demonstrating its significant promise of proposed strategy for large-scale synthesis of NaV{sub 6}O{sub 15} as cathode with high-capacity and high energy density for LIBs.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Directional preparation of cobalt oxide nanoflakes grown on cobalt nanowires as composite cathode for high-performance alkaline batteries

Graphical abstract: Self-supported hierarchical porous CoO@Co core/shell arrays are prepared by combined hydrothermal plus electrodeposition methods and exhibit good electrochemical performances with high capacity & stable cycling life. - Highlights: • Construct self-supported porous CoO@Co core/branch arrays. • Porous CoO@Co composite arrays show high capacity and good cycling life. • Hierarchical porous composite structure is favorable for fast ion/electron transfer. - Abstract: Synthesis of multicomponent core/branch arrays is important for development of advanced energy storage devices. Herein we fabricate porous CoO@Co core/branch arrays by successive hydrothermal + electrodeposition methods CoO nanoflakes branch is uniformly coated on the Co nanowire core forming composite core/branch arrays (CBAs). The CoO@Co CBAs possess combined properties of highly porous structure and strong mechanical stability. As cathode for alkaline batteries, the obtained CoO@Co CBAs exhibit good electrochemical performances with high a capacity of 91.5 mAh g{sup −1} at 1 A g{sup −1} and stable high-rate cycling life (73.5 mAh g{sup −1} after 12,000 cycles at 10 A g{sup −1}). The hierarchical core/branch architecture provides positive roles in the enhancement of electrochemical properties with fast electronic transportation path, and short diffusion channels of ions. Our finding offers a new way to construct high-performance cathode of alkaline batteries.

36 MATERIALS SCIENCE↗
DOE OSTI2017

α-MoO{sub 3} nanowire bundles fabricated from a self-assembled organic–inorganic precursor as cathodes for lithium-ion batteries

Graphical abstract: α-MoO{sub 3} nanowire bundles are prepared at ambient pressure as cathodes for lithium-ion batteries, which can run up to 600 cycles. - Highlights: • MoO{sub 3} nanowire bundles have been prepared. • The preparation method is facile at ambient pressure. • MoO{sub 3} nanowire bundles show good cycle performance. - Abstract: We report here the facile preparation of α-MoO{sub 3} nanowire bundles from the decomposition of the self-assembled organic–inorganic precursor Mo{sub 3}O{sub 10}(C{sub 6}H{sub 8}N){sub 2}·2H{sub 2}O at ambient pressure. The obtained samples have been fully characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analyses. As for cathodes of lithium-ion batteries, the as-obtained α-MoO{sub 3} nanowire bundles can initially reach a discharge capacity of 195 mAh g{sup −1} and run up to 600 cycles with a 37% capacity retention at a current density of 100 mA g{sup −1}.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Facile synthesis of fusiform layered oxides assisted by microwave as cathode material for lithium-ion batteries

Graphical abstract: Fusiform layered oxides synthesized by microwave solvothermal reaction with excellent electrochemical property as cathode material for lithium-ion batteries. - Highlights: • LiMn{sub 0.25}Ni{sub 0.5}Co{sub 0.25}O{sub 2} is obtained by microwave solvothermal reaction. • Material synthesized at 800 °C exhibits fusiform hierarchical morphology. • High initial discharge capacity of 183 mAh g{sup −1} is reached at 0.1C. • 154 mAh g{sup −1} is remained with a capacity retention of 84.2% after 100 cycles. • Excellent rate capability is also obtained. - Abstract: A facile microwave solvothermal reaction is performed to synthesize novel LiMn{sub 0.25}Ni{sub 0.5}Co{sub 0.25}O{sub 2} ternary layered oxide with 1 D fusiform morphology. Scanning electron microscopy (SEM) images show that material synthesized at 800 °C well keeps the fusiform morphology of the precursor with a particle size of 100–300 nm. All the three elements are perfectly dispersed and a well-formed layered structure is obtained. Thus, good electrochemical performances with high initial discharge capacity of 183 mAh g{sup −1} is reached. Furthermore, high discharge capacity of 154 mAh g{sup −1} is remained with a capacity retention of 84.2% after 100 cycles at 20 mA g{sup −1}. Excellent rate capability is also obtained with high discharge capacity of 99 mAh g{sup −1} at 2000 mA g{sup −1}. It seems such facile microwave solvothermal method is one of the most promising candidates for preparing ternary layered oxides with excellent electrochemical properties as cathode material for lithium ion batteries.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Synthesis and physical properties of NaxTO2 (T = Mn, Co) nanostructures for cathode materials in Na-ion batteries

Highlights: • Synthesis of stable Na{sub x}TO{sub 2} (T = Mn, Co) nanostructures using a sol–gel method. • Absence of any long-range magnetic ordering in both compounds till 5 K. • Activated type conduction at high temperatures and VRH at low temperatures in Na{sub x}CoO{sub 2}. • Disorder assisted VRH conduction takes place in Na{sub x}MnO{sub 2} near room temperature. • Cyclic voltammetry confirm reversibility of Na ion in a coin cell using Na{sub x}TO{sub 2} cathode. - Abstract: We prepared Na{sub x}TO{sub 2} (T = Mn, Co) nanostructures to use as cathode material in Na-ion batteries. The Rietveld refinement of X-ray diffraction data confirms the hexagonal symmetry. Scanning and transmission electron microscopy measurements show hexagonal and rod-shape morphology for T = Co and Mn, respectively. The magnetic measurements indicate the presence of variable oxidation states of Mn/Co ions, but no long range ordering till 5 K. We find that the Na{sub 0.6}MnO{sub 2} is highly insulating whereas Na{sub 0.7}CoO{sub 2} is semiconducting in nature. The conduction in Na{sub 0.7}CoO{sub 2} takes place through both variable range hopping (VRH) as well as activation mechanisms in different temperature ranges. However, for Na{sub 0.6}MnO{sub 2} the VRH prevails at elevated temperatures. Furthermore, the coin cells have been fabricated and tested the electrochemical behavior using cyclic voltammetry, which confirms the reversibility of Na-ions during intercalation/de-intercalation.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2019

Improving the reversibility of the H2-H3 phase transitions for layered Ni-rich oxide cathode towards retarded structural transition and enhanced cycle stability

While the layered Ni-rich LiNi x Co y Mn 1-x-y O 2 (0.7 + ions delithiated during charging will leave the structure of the layered Ni-rich materials more vulnerable. In this report, we propose that improving the reversibility of H2-H3 phase transition for Ni-rich materials is effective to tackle this challenge. It has been confirmed that the generation of microcracks and structural transformations have been suppressed since the H2-H3 phase transition becomes reversible, while which shows little effect on capacity delivery. Consequently, using Ni-rich LiNi 0.9 Co 0.1 O 2 as the cathode material, the 100 th capacity retention cycling at 38mAg -1 has been improved remarkably from 69.7% to 97.9% by adopting this strategy. Hence, it should be a novel solution to realize both high capacity and stable cyclability for the Ni-rich cathodes.

25 ENERGY STORAGE↗
DOE OSTI2019

Manipulation of an ionic and electronic conductive interface for highly-stable high-voltage cathodes

A stable and conductive interface is one of the decisive factors in manipulating the performance of high voltage LiNi 0.5 Mn 1.5 O 4 (LNMO) cathode for Li-ion batteries. Herein, a hybrid Li 3 PO 4 -TiO 2 coating layer is designed as an interfacial material via controllable atomic layer deposition (ALD) on LNMO. The coating acts not just as a physical barrier to prevent the side-reactions between cathode and electrolyte at high voltage, more importantly, the hybrid coating material improves both interfacial ionic and electronic conductivities to build facile Li-ion and electron diffusion pathways for LNMO. The optimized LNMO demonstrates improved rate capability and long-life stability. The capacity retention is 81.2% comparing with 47.4% of bare LNMO at 0.5C after 300 cycles. Detailed surface structural evolution is studied via X-ray absorption near edge spectroscopy and transmission electron microscopy. Furthermore, this work provides new insights of hybrid interfacial design via ALD and promotes novel electrode architectures for batteries.

25 ENERGY STORAGE↗
DOE OSTI2020

Stabilizing and understanding the interface between nickel-rich cathode and PEO-based electrolyte by lithium niobium oxide coating for high-performance all-solid-state batteries

The pursuit of high energy density and safe lithium ion batteries (LIBs) is the urgent goal for the development of next-generation electric vehicles (EVs). All-solid-state batteries (ASSBs) with the combination of poly(ethylene oxide) (PEO)-based solid polymer electrolyte (SPE) and Ni-rich lithium nickel manganese cobalt oxide LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode are promising candidates for EVs due to their improved energy density and safety. However, the low electrochemical oxidation window of PEO-based SPE and the instability of NMC811 at the charge/discharge process seriously restrict the battery performance. Herein, a high voltage stable solid-state electrolyte layer lithium niobium oxide (LNO) is coated on the NMC811 electrode surface by atomic layer deposition for stabilizing NMC811-PEO solid polymer batteries. Electrochemical tests show that LNO coating can stabilize the NMC811 active materials and mitigate the decomposition of SPE upon the cycling process, rendering a good performance of NMC811-PEO solid polymer battery. Mechanism studies by SEM, STEM, XAS, and XPS disclose that the uncoated NMC811 suffers from chemomechanical degradations along with oxygen release triggering the decomposition of SPE, which results in unstable cathodic electrolyte interphase. With LNO coating, chemomechanical degradations and oxygen release are inhibited and the decomposition of SPE is mitigated. This paper renders a stable and high-performance high-energy-density SSB for high voltage application, which paves the way toward next-generation solid-state LIBs.

25 ENERGY STORAGE↗
DOE OSTI2020

Understanding fundamental effects of Cu impurity in different forms for recovered LiNi 0.6 Co 0.2 Mn 0.2 O 2 cathode materials

When identifying and developing lithium ion battery recycling technologies, understanding the role of impurities is always a concern as they may have an impact on electrochemical performance, material stability, or lifetime for recovered active materials. In this work we show that Cu impurity in different forms could play very different roles on the recovered LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622). Cu metal impurity could easily short the cell, while Cu ion impurity could play a positive role due to partially substitution of the Ni 2+ sites to lower the cation mixing degree. In specific, NCM622 material with certain amount (0.34 at%) of Cu ion impurity delivers high initial specific charge/discharge capacity of 211.8 and 186.0 mAh g -1 at 0.05 C, which are 12.2 and 14.1 mAh g -1 higher than those of virgin NCM622 cathode. Moreover, a superior retention capacity of 171.3 mAh g -1 after 90 cycles at 0.33 C, and striking rate capability are achieved in this NCM622 cathode sample. These results clearly indicate that Cu metal impurity should be avoided and the ionic Cu impurity should be controlled with optimal concentration during recycling process for spent LIBs.

25 ENERGY STORAGE↗
DOE OSTI2020

Correlating the phase evolution and anionic redox in Co-Free Ni-Rich layered oxide cathodes

Current trend of high-capacity Ni-rich layered cathode is to develop high-Ni and low-Co or Co-free oxides. The high Ni content layered oxides provide great advantages in capacity, cost and environmental benignity, similar to LiNiO 2 parent compound. But they also inherit drawbacks in structural and chemical instability at high voltages upon cycling. As such, elemental substitution plays a profound role in addressing these challenges. This work elucidates the roles of Al doping in cationic redox and anionic oxygen activity in LiAl x Ni 1-x O 2 using combined X-ray absorption spectroscopy (XAS), resonant inelastic X-ray scattering (RIXS) as well as operando differential electrochemical mass spectrometry (DEMS). Using synchrotron wide-angle X-ray scattering (WAXS), we extrapolate a general principle of phase transition and its coupling with lattice anionic oxygen redox. These findings shed light on the advancement of high-capacity, stable-cycling and safe-operating Ni-rich cathode materials for next generation Li-ion batteries.

25 ENERGY STORAGE↗
DOE OSTI2021

Tunning the linkage of structure units to enable stable spinel-based cathode in the wide potential window

The low practical capacity (<140 mA h g –1 ) of spinel phase LiMn 2–x Ni x O 4 (0 < x < 1) excludes it from high energy density lithium ion batteries (LIBs) for powering electric vehicles. Extending the operating potential window from 3.0 to 4.8 V to 2.0–4.8 V can double the capacity, but result in fast capacity decay due to the drastic cubic-tetragonal phase transition below 3.0 V, induced by serious Jahn-Teller (J-T) distortion of structure units (Mn 3+ )O 6 octahedra. Herein, we propose a novel strategy to suppress J-T distortion by tuning the linkage of structure units MnO 6 octahedra. The original full-vertex-sharing LiO 4 tetrahedra around MnO 6 octahedra in spinel phase are partially replaced by edge-sharing LiO 6 octahedra, which relate Mn-O bonds along the dz 2 direction with those along the d xy plane, thus significantly mitigating J-T distortion and suppressing the phase transition when discharged to 2.0 V. Following this strategy, the prepared spinel-based cathode achieves a high reversible capacity of about 290 mA h g –1 and an energy density up to 957 W h kg –1 with improved cycling stability. Furthermore, this work finds a new opportunity for the traditional spinel cathode towards applications in high energy density LIBs in a low cost and sustainable manner.

25 ENERGY STORAGE↗
DOE OSTI2022

Reviving the rock-salt phases in Ni-rich layered cathodes by mechano-electrochemistry in all-solid-state batteries

The rock-salt phase (RSP) formed on the surface of Ni-rich layered cathodes in liquid-electrolyte lithium-ion batteries is conceived to be electrochemically "dead". Here we show massive RSP forms in the interior of LiNi x Mn y Co (1–x-y) O 2 (NMC) crystals in sulfide based all solid state batteries (ASSBs), but the RSP remains electrochemically active even after long cycles. The RSP and the layered structure constitute a two-phase mixture, a material architecture that is distinctly different from the RSP in liquid electrolytes. The tensioned layered phase affords an effective percolation channel into which lithium is squeezed out of the RSPs by compressive stress, rendering the RSPs electrochemically active. Consequently, the ASSBs with predominant RSP in the NMC cathode deliver remarkable long cycle life of 4000 cycles at high areal capacity of 4.3 mAh/cm 2 . Our study unveils distinct mechano-electrochemistry of RSPs in ASSBs that can be harnessed to enable high energy density and durable ASSBs.

25 ENERGY STORAGE↗
DOE OSTI2019

Next-Generation Cathode Materials for Non-aqueous Potassium-Ion Batteries

Potassium-ion batteries have recently attracted considerable attention as cost-effective alternatives to lithium-ion batteries for large-scale energy storage. However, a major obstacle to the practical application of this emerging technology is the lack of suitable cathode materials that are capable of delivering high gravimetric/volumetric energy, stable cycle life, and high rate capability. Here in this review article, we review the recent progress in cathodes development for potassium-ion batteries. These materials are categorized into four types: layered oxides, Prussian blue analogs, poly-anion, and organic compounds. Based on our critical review of the reported literature, we identify poly-anion compounds as a class of promising candidates among all types and provide suggestions for future optimization.

25 ENERGY STORAGE↗