Search NASA⌕ Search

SEARCH · Search NASA

Results for “dendrite-free”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

High-performance all-solid-state Li–S batteries enabled by an all-electrochem-active prelithiated Si anode

The development of all-solid-state Li–S batteries has been greatly impeded by dendrite growth and dendrite penetration, which are both related to the Li metal anode. As a compromised alternative, we report lithium silicide (Li x Si) as a dendrite-free and high-capacity anode with Li source. Here, the as-synthesized Li x Si is relatively soft, highly electronically conductive, and with a high Li diffusivity. These distinctive properties make Li x Si anode viable as an “all-electrochem-active” electrode (consisted of 100 wt.% Li x Si). Compared with the typical composite electrode, the all-electrochem-active electrode not merely maximizes the electrode-level energy density but also minimizes the electrolyte-related interfacial degradation. Li x Si symmetric cell demonstrates a reversible cycling at 4 mA cm –2 for over 320 h. Stress change and morphological evolution of the Li x Si electrode are investigated upon dealloying/alloying. When paired with a S cathode (active mass loading of 3 mg cm –2 ), Li x Si–S full cell shows a good cycling behavior over 500 cycles and rate performance (69% capacity retained at 1.2C) even at 25 °C.

25 ENERGY STORAGE↗
DOE OSTI2024

Lithiophilic CoF 2 @C hollow spheres towards spatial lithium deposition for stable lithium metal batteries

Lithium metal (LM) is a promising anode for next-generation batteries due to its high theoretical capacity and low electrode potential. Nonetheless, side reactions, volume change, and unwanted lithium dendrite growth seriously limit the practical application of LM. Herein, with the aid of a hard template approach, a novel lithiophilic CoF 2 -carbon hollow sphere (CoF 2 @C-HS) composite material is successfully prepared via a facile in-situ fluorination and etching strategy. The lithiophilic CoF 2 acts as nucleation sites to reduce nucleation overpotential as well as induces the spatial Li deposition and the formation of LiF-rich solid electrolyte interphase (SEI), and the hollow carbon matrix can enhance the electrical conductivity and offer free space for LM deposition. Theoretical simulations reveal that the synergistic effect of lithiophilic CoF 2 and hollow carbon matrix homogenizes the electric field distribution and Li + flux. Benefiting from these advantages, the CoF 2 @C-HS-modified copper substrate electrode delivers an enhanced Coulombic efficiency (CE) of 93.7% for 280 cycles at 1 mA cm –2 and 1 mA h cm –2 . The symmetrical cell using CoF 2 @C-HS can stably cycle more than 1800 h with a low voltage hysteresis of 11 mV at a current density of 0.5 mA cm –2 and an areal capacity of 0.5 mA h cm –2 . Moreover, the Li@CoF 2 @C-HS composite anode enables more than 300 stable cycles at 1 C with a capacity retention of 95% in LiFePO 4 -based full cell and 110 stable cycles at 1 C in LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811)-based high-voltage full cell. Finally, this work might shed a new light on designing lithiophilic hosts to spatially confine LM deposition, realizing dendrite-free LM anodes and the practical applications of LM batteries.

25 ENERGY STORAGE↗
DOE OSTI2023

Stabilizing magnesium plating by a low-cost inorganic surface membrane for high-voltage and high-power Mg batteries

Mg batteries with halide-free electrolytes suffer from poor stability of the Mg metal anode due to electrolyte decomposition. Here, we report a low-cost zeolite membrane supported on Mg to address this challenge. It vastly reduces the population (hence decomposition) of free diglyme at the Mg/electrolyte interface, while allowing facile transport of Mg 2+ cations through the membrane. We demonstrate dendrite-free Mg plating/stripping performance in a magnesium tetrakis(hexafluoroisopropyloxy)borate/diglyme electrolyte with a 750-fold extended lifetime (over 6,000 h) and a high coulombic efficiency of ~98%. The prototype Mo 3 S 4 cathode paired with the protected Mg anode shows 91% capacity retention over 200 cycles. Importantly, this membrane protects soluble species in a high-voltage organic polymer cathode from being reduced at the anode via shuttling, achieving a full cell with a 3.5 V cutoff voltage. This results in a high specific energy density of 320 Wh kg –1 and a power density of 1,320 W kg –1 based on cathode mass.

25 ENERGY STORAGE↗
DOE OSTI2023

Anion modification for stable solid electrolyte interphase in anode-free lithium metal batteries

The durability of anode-free Li metal batteries is largely limited by the undesired Li plating/stripping irreversibility on the current collector due to the infinite volume change, uncontrollable Li dendrite growth, and continuous parasitic reactions between Li metal and the electrolyte. To address these challenges, the formation of a stable and robust solid electrolyte interphase (SEI) with high ionic conductivity and strong mechanical strength is critical. Here, we developed an advanced electrolyte by introducing LiNO 3 into the localized high concentration electrolyte (LHCE) with lithium bis(fluorosulfonyl)imide (LiFSI) salt, 1,2-dimethoxyethane (DME) solvent, and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether (TFTE) diluent to in situ construct a LiF and Li x N y O z co-enriched passivation layer on the Cu current collector. The synergetic effect of high mechanical strength of LiF and high ionic conductivity of Li x N y O z endows the Li metal anode with a high Coulombic efficiency (CE) of 99.35%. In conclusion, in anode-free Li metal pouch cell using LiFePO 4 (LFP) as a cathode holds an exceptionally improved capacity retention under the charging/discharging rate of 1/3 C, demonstrating great promise for developing dendrite-free and safe Li metal batteries.

25 ENERGY STORAGE↗
DOE OSTI2022

Uniform lithiophilic layers in 3D current collectors enable ultrastable solid electrolyte interphase for high-performance lithium metal batteries

Uniform lithium plating/stripping during charging/discharging in 3D lithiophilic current collectors (3DLCC) is essential to suppress growth of lithium dendrites and to mitigate infinite volume variations of lithium metal for long-lived lithium metal batteries. Additionally, this study reveals the decisive role played by uniformity of the lithiophilic layer of the 3DLCC in achieving uniform lithium plating/stripping. Herein, a series of metal oxide-based 3DLCCs are successfully fabricated with a simple and an ultrafast solution combustion method, from which formation of a uniform and stable lithium dendrite-free solid electrolyte interphase via a uniform lithiophilic layer is demonstrated. Taking Co 3 O 4 as the lithiophilic material deposited on a nickel foam as the 3DLCC (Co@NF) for a proof of concept, the loading amount of Co 3 O 4 , closely correlated with the uniformity of the Co 3 O 4 layer, is modulated to optimize its lithium ion hosting performances. With a uniform Co 3 O 4 layer grown in the 3DLCC, an ultralow nucleation overpotential of 33.4 mV is achieved in half-cell tests at 1 mA cm -2 and 1 mAh cm -2 , and a high Coulombic efficiency of 97.1% is maintained after 210 cycles under a severe cycling condition of 2 mA cm -2 and 1 mAh cm -2 . A small polarization voltage of 13 mV together with an ultralong cycle life of 2400 h at 0.5 mA cm -2 and 1 mAh cm -2 in symmetric Li cells is achieved. Moreover, the composite Li anode delivers sensational rate capability and cyclability in full-cells. This work not only provides new and valuable insights into the interphasial chemistry of solid electrolyte interphase layers, but also sheds light on the development of ultrastable lithium metal batteries.

25 ENERGY STORAGE↗
DOE OSTI2022

Polyvinyl alcohol coating induced preferred crystallographic orientation in aqueous zinc battery anodes

The development of rechargeable aqueous zinc batteries is mainly hindered by the Zn anode, which suffers from dendrite growth, corrosion, hydrogen evolution, and surface passivation. Herein, a thin polyvinyl alcohol (PVA) coating layer on Zn anode has enabled dendrite-free, long-life aqueous Zn batteries by effectively regulating the interfacial ion diffusion and inducing the homogeneous Zn nucleation and deposition of stacked plates with preferentially crystallographic orientation along (002) Zn planes. The PVA@Zn anode achieved an ultralong cycle lifespan of thousands of hours at 0.25 and 1 mA cm -2 . Outstanding durability under a deep cycling capacity (5 mA h cm -2 ), high current density (10 mA cm -2 ), and long duration conditions were achieved. The superior cyclability of PVA@Zn anode was also demonstrated in PVA@Zn//V 2 O 5 full cells. In conclusion, the insights of PVA induced Zn deposition with preferred crystal orientation and interfacial regulation shed light on the future development of stable Zn anodes.

Crystallographic orientation↗
DOE OSTI2021

Maintaining a Flat Li Surface during the Li Stripping Process via Interface Design

Electroplating has been the main focus in mitigating the dendrite growth on the Li-metal electrode; however, the stripping process is equally critical, since the nonsmooth Li surface during stripping will lead to nonuniform local current density, planting the seeds for dendrite growth. In this paper, density functional theory (DFT) and kinetic Monte Carlo (KMC) techniques were combined to investigate the vacancy evolution in Li interfaced with different solid–electrolyte interphase (SEI) materials. It was found that the lithiophilic interface, such as Li/Li 2 O, repels vacancies into the bulk Li, so Li atoms can quickly fill the Li vacancies near the Li/Li 2 O interface and maintain a smooth Li surface. In contrast, the lithiophobic interface, such as Li/LiF, traps Li vacancies toward the interface, and the accumulated Li vacancies form voids and roughen the surface. The predicted critical stripping current density, below which a smooth Li surface will be maintained, is therefore much faster at the lithiophilic interface than that at the lithiophobic interface. It was further revealed that the lithiophilicity at different SEI or coating materials can be ranked as Li/Li 2 O > Li/LiPON > Li/Li 2 CO 3 > Li/LiF based on the calculated interfacial adhesion and accumulation of electron density at the interface. Furthermore, this suggests that interface and coating design at nanoscale can be effective for maintaining a smooth Li surface during the stripping process, solving another challenge to achieving a dendrite-free Li-metal electrode in both liquid and solid electrolytes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Active Dendrite Suppression by Ferroelectric Membrane Separators in Rechargeable Batteries

Anodic dendrite formation is a critical issue in rechargeable batteries and often leads to poor cycling stability and quick capacity loss. Prevailing strategies for dendrite suppression aim at slowing down the growth rate kinetically but still leaving possibilities for dendrite evolution over time. Herein, we report a complete dendrite elimination strategy using a mesoporous ferroelectric polymer membrane as the battery separator. The dendrite suppression is realized by spontaneously reversing the surface energetics for metal ion reduction at the protrusion front, where a positive piezoelectric polarization is generated and superimposed as the protrusion compresses the separator. This effect is demonstrated first in a Zn electroplating process, and further in Zn–Zn symmetric cells and Zn–NaV 3 O 8 ·1.5H 2 O full cells, where the dendritic Zn anode surfaces are completely turned into featureless flat surfaces. Consequently, a substantially longer charging/discharging cycle is achieved. Furthermore, this study provides a promising pathway toward high-performance dendrite-free rechargeable batteries.

25 ENERGY STORAGE↗
DOE OSTI2022

Dual Passivation of Cathode and Anode through Electrode–Electrolyte Interface Engineering Enables Long-Lifespan Li Metal–SPAN Batteries

The reliability and durability of lithium metal (Li 0 )–sulfur batteries are largely limited by the undesired Li 0 plating-stripping irreversibility and the detrimental polysulfide dissolution, yet approaches that can simultaneously address the above anodic and cathodic problems are scarce. In this study, we report the stable operation of a Li 0 -SPAN (sulfurized polyacrylonitrile) battery via an anode–cathode dual-passivation approach. By combination of a fluorinated localized high concentration electrolyte (LHCE) and a Li 3 N-forming additive (TMS-N 3 ), robust and highly conductive electrode passivation layers are formed in situ on the surface of both the Li 0 anode and the SPAN cathode. The resulting highly reversible, dendrite-free, and high-density Li 0 plating morphology enables a high Coulombic efficiency of 99.4%. Advanced tender energy X-ray spectroscopy also reveals the eliminated Li 2 S formation and minimized polysulfide dissolution in SPAN cathodes, leading to a high capacity of 580 mAh/g SPAN and stable cycling with negligible capacity decay (0.7%) for 800 cycles. This electrode–electrolyte interphase engineering strategy has tackled the major limitations of Li–S batteries in both ether- and carbonate-based electrolyte systems and under a wide temperature range from –10 to +50 °C, thus providing insightful guidelines for the rational design of highly durable and high-energy-density Li 0 -S batteries.

25 ENERGY STORAGE↗
DOE OSTI2024

Solvent-Mediated, Reversible Ternary Graphite Intercalation Compounds for Extreme-Condition Li-Ion Batteries

Traditional Li-ion intercalation chemistry into graphite anode exclusively utilizes the co-intercalation-free or co-intercalation mechanism. The latter mechanism is based on ternary graphite intercalation compounds (t-GICs), where glyme solvents were explored and proved to deliver unsatisfied cyclability in LIBs. Herein, we report a novel intercalation mechanism, that is, in-situ synthesis of t-THF-GICs in the tetrahydrofuran (THF) electrolyte via a spontaneous, controllable reaction between binary-GICs and free THF molecules during initial graphite lithiation. The spontaneous transformation from b-GIC to t-GIC, which is different from conventional co-intercalation chemistry, is characterized and quantified via operando synchrotron X-ray and electrochemical analyses. The resulting t-GIC chemistry obviates the necessity for complete Li-ion desolvation, facilitating rapid kinetics and synchronous charge/discharge of graphite particles even under high current densities. Consequently, the graphite anode demonstrates unprecedented fast charging (1 min), dendrite-free low-temperature performance, and ultralong lifetimes exceeding 10,000 cycles. Full cells coupled with layered cathode, display remarkable cycling stability upon a 15-min charging and excellent rate capability even at -40 °C. Furthermore, our chemical strategies are shown to extend beyond Li-ion batteries to encompass Na-ion and K-ion batteries, underscoring their broad applicability. Our work contributes to the advancement of graphite intercalation chemistry and presents a low-cost, adaptable approach to achieving fast-charging and low-temperature batteries.

25 ENERGY STORAGE↗
DOE OSTI2022

Suppressing electrolyte-lithium metal reactivity via Li + -desolvation in uniform nano-porous separator

Lithium reactivity with electrolytes leads to their continuous consumption and dendrite growth, which constitute major obstacles to harnessing the tremendous energy of lithium-metal anode in a reversible manner. Considerable attention has been focused on inhibiting dendrite via interface and electrolyte engineering, while admitting electrolyte-lithium metal reactivity as a thermodynamic inevitability. Here, we report the effective suppression of such reactivity through a nano-porous separator. Calculation assisted by diversified characterizations reveals that the separator partially desolvates Li + in confinement created by its uniform nanopores, and deactivates solvents for electrochemical reduction before Li 0 -deposition occurs. The consequence of such deactivation is realizing dendrite-free lithium-metal electrode, which even retaining its metallic lustre after long-term cycling in both Li-symmetric cell and high-voltage Li-metal battery with LiNi 0.6 Mn 0.2 Co 0.2 O 2 as cathode. The discovery that a nano-structured separator alters both bulk and interfacial behaviors of electrolytes points us toward a new direction to harness lithium-metal as the most promising anode.

25 ENERGY STORAGE↗
DOE OSTI2023

Enabling selective zinc-ion intercalation by a eutectic electrolyte for practical anodeless zinc batteries

Abstract Two major challenges hinder the advance of aqueous zinc metal batteries for sustainable stationary storage: (1) achieving predominant Zn-ion (de)intercalation at the oxide cathode by suppressing adventitious proton co-intercalation and dissolution, and (2) simultaneously overcoming Zn dendrite growth at the anode that triggers parasitic electrolyte reactions. Here, we reveal the competition between Zn 2+ vs proton intercalation chemistry of a typical oxide cathode using ex-situ/ operando techniques, and alleviate side reactions by developing a cost-effective and non-flammable hybrid eutectic electrolyte. A fully hydrated Zn 2+ solvation structure facilitates fast charge transfer at the solid/electrolyte interface, enabling dendrite-free Zn plating/stripping with a remarkably high average coulombic efficiency of 99.8% at commercially relevant areal capacities of 4 mAh cm −2 and function up to 1600 h at 8 mAh cm −2 . By concurrently stabilizing Zn redox at both electrodes, we achieve a new benchmark in Zn-ion battery performance of 4 mAh cm −2 anode-free cells that retain 85% capacity over 100 cycles at 25 °C. Using this eutectic-design electrolyte, Zn | |Iodine full cells are further realized with 86% capacity retention over 2500 cycles. The approach represents a new avenue for long-duration energy storage.

25 ENERGY STORAGE↗
DOE OSTI2024

Effect of solid-electrolyte pellet density on failure of solid-state batteries

Abstract Despite the potentially higher energy density and improved safety of solid-state batteries (SSBs) relative to Li-ion batteries, failure due to Li-filament penetration of the solid electrolyte and subsequent short circuit remains a critical issue. Herein, we show that Li-filament growth is suppressed in solid-electrolyte pellets with a relative density beyond ~95%. Below this threshold value, however, the battery shorts more easily as the density increases due to faster Li-filament growth within the percolating pores in the pellet. The microstructural properties (e.g., pore size, connectivity, porosity, and tortuosity) of $$75\%{{{{{\rm{L}}}}}}{{{{{{\rm{i}}}}}}}_{2}{{{{{\rm{S}}}}}}-25\%{{{{{{\rm{P}}}}}}}_{2}{{{{{{\rm{S}}}}}}}_{5}$$ 75 % L i 2 S − 25 % P 2 S 5 with various relative densities are quantified using focused ion beam–scanning electron microscopy tomography and permeability tests. Furthermore, modeling results provide details on the Li-filament growth inside pores ranging from 0.2 to 2 μm in size. Our findings improve the understanding of the failure modes of SSBs and provide guidelines for the design of dendrite-free SSBs.

25 ENERGY STORAGE↗
DOE OSTI2024

Robust battery interphases from dilute fluorinated cations

Controlling solid electrolyte interphase (SEI) in batteries is crucial for their efficient cycling. Herein, we demonstrate an approach to enable robust battery performance that does not rely on high fractions of fluorinated species in electrolytes, thus substantially decreasing the environmental footprint and cost of high-energy batteries. In this approach, we use very low fractions of readily reducible fluorinated cations in electrolyte (~0.1 wt%) and employ electrostatic attraction to generate a substantial population of these cations at the anode surface. As a result, we can form a robust fluorine-rich SEI that allows for dendrite-free deposition of dense Li and stable cycling of Li-metal full cells with high-voltage cathodes. Our approach represents a general strategy for delivering desired chemical species to battery anodes through electrostatic attraction while using minute amounts of additive.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Interface-induced fast Li+ transport in mixed ionic–electronic conductors

Interfacial instability between lithium metal and solid-state electrolytes limits the performance of all-solid-state lithium metal batteries (ASSLBs), leading to parasitic reactions, non-uniform Li+ flux, and dendrite growth. Here, we develop a composite interlayer composed of the anti-perovskite Li2OHCl0.75Br0.25 (AP) and carbon nanotubes (CNTs) to enhance both interfacial stability and ionic transport. The AP–CNT interlayer exhibits enhanced Li+ conductivity arising from interfacial electron transfer from AP to CNTs, which generates a built-in electric field that facilitates Li+ migration. Lithium symmetric cells incorporating this interlayer achieve a high critical current density of 2.4 mA cm−2 at 55 °C. This design integrates chemical robustness with coupled ion–electron transport, offering a generalizable strategy for safe, dendrite-free, and high-performance ASSLBs.

He, Chenche↗
DOE OSTI2022

Electrochemically Stable High Energy Density Lithium-Sulfur Batteries

Lithium-Sulfur batteries (LSB) have emerged as one of the strong contenders for high energy density rechargeable batteries in the Li-ion battery domain. The LSB system is considered as the most promising to achieve the next milestone in energy density of 500 Wh/kg. However, the LSB system is plagued with problems of polysulfide formation which are soluble in the organic electrolyte leading to loss in capacity and eventual cell failure. The problem is further compounded by dendrite formation on the Li anode during electrochemical cycling leading to puncturing of the separator causing eventual short-circuiting of the cell and consequent heat generation resulting in major safety hazards of flammability of the organic liquid electrolyte and impending explosion. This chapter describes various approaches developed to combat both cathode and anode issues. These involve synthesis and characterization of complex framework materials (CFMs) for confining the polysulfides and sulfur in the LSB cathodes. The CFMs include a CFM host and a coating applied to the CFM host, which includes one or more form of an electronic conductor, a lithium-ion conductor and a functional electrocatalyst for electrocatalytically converting the soluble polysulfides to Li 2 S. Further, sulfur is infiltrated into the CFM host creating a sulfur-carbon linkage serving as effective anchors for trapping the ensuing polysulfides. The systems have been tested in coin cells and pouch cells with metallic Li anodes under lean electrolyte conditions of 3-4 μl/mg of electrolyte (E) to sulfur (S) ratios showing promise and feasibility. New emergent dendrite-free alloys have also been identified to test against pure Li and CFM cathodes in coin cell and pouch cell configurations under lean electrolyte conditions. Results of these studies are described and discussed with thoughts on future directions.

25 ENERGY STORAGE↗