Ji-Guang Zhang

Pacific Northwest National Laboratory | PNNL

Significant progresses have been made on the long-term cycle life of lithium (Li) metal batteries (LMBs) in recent years. However, far less progress has been reported on the calendar life of LMBs. Here we will give an overview on the main challenges and progresses in this filed. A perspective on the path towards long-term calendar life of LMBs will...

Lithium-sulfur (Li-S) battery is one of the most promising energy storage systems owning to their high energy density and cost-effective sulfur source. However, their practical application is still hindered by challenges such as the severe shuttle effect of lithium polysulfides (LiPS) and severe lithium corrosion that lead to substantial self-disch...

Silicon (Si) has been regarded as a promising anode for Li-ion batteries due to its high theoretical capacity (4200 mAh/g) compared to graphite anode (372 mAh/g). However, it undergoes significant volume changes (~ 300%) during lithiation and delithiation, leading to particle pulverization and continuous electrolyte decomposition on Si surface, whi...

High voltage anode-free lithium batteries (AFLBs) hold great potential for achieving superior energy density compared to the conventional batteries. However, ensuring a prolonged cycle life for AFLBs remains a significant challenge due to persistent side reactions between the lithium deposited on the anode current collector and the electrolyte. To...

During the last few decades, silicon (Si) has been extensively investigated as the next generation of anode material for lithium (Li)-ion batteries (LIBs) due to its high theoretical capacity (~ 4200 mAh g ⁻¹ ) which is more than ten times larger than those of graphite anode materials. However, because of the huge volume changes (~ 300%) of Si duri...

Despite the great achievement in the development of rechargeable lithium (Li) metal batteries (LMBs) with high energy densities, their practical application is still facing difficulties due to the intrinsic issues of Li metal anode (LMA) including high reactivity and dendritic Li formation which cause low Coulombic efficiency, constant loss of Li a...

Passivation of both anode and cathode surfaces by the inorganic-rich solid electrolyte interphases (SEI) is a very efficient approach to extent the cycle life of rechargeable high-voltage lithium (Li) metal batteries (LMBs). In this work, a fluorinated ether with weakly-solvating ability, termed DB, was used as a diluent as well as a co-solvent in...

The high energy density advantage of lithium (Li) metal batteries (LMBs) makes them increasingly desirable; however, problems such as strong reactivity and dendrite growth of Li metal anode limit their practical uses. In this work, a novel Li‐containing glycerol (LiGL) or lithicone protection layer on a 50 μm thick Li metal anode is employed for im...

The lifespan of lithium (Li) metal batteries (LMBs) can be greatly improved by the formation of inorganic‐rich electrode‐electrolyte interphases (EEIs) (including solid‐electrolyte interphase on anode and cathode‐electrolyte interphase on cathode). In this work, a localized high‐concentration electrolyte containing lithium bis(fluorosulfonyl)imide...

Sodium (Na)‐metal batteries (SMBs) are considered one of the most promising candidates for the large‐scale energy storage market owing to their high theoretical capacity (1,166 mAh g⁻¹) and the abundance of Na raw material. However, the limited stability of electrolytes still hindered the application of SMBs. Herein, sulfolane (Sul) and vinylene ca...

The energy storage density of Li‐ion batteries can be improved by replacing graphite anodes with high‐capacity Si‐based materials, though instabilities have limited their implementation. Performance degradation mechanisms that occur in Si anodes can be divided into cycling stability (capacity retention after repeated battery cycles) and calendar ag...

Polyolefin separators are the most common separators used in rechargeable lithium (Li)‐ion batteries. However, the influence of different polyolefin separators on the performance of Li metal batteries (LMBs) has not been well studied. By performing particle injection simulations on the reconstructed three‐dimensional pores of different polyethylene...

Si is one of the most promising anode materials for the next generation of lithium (Li) ion batteries (LIBs). Recently, we have developed a porous Si with a unique carbon coating structure (“carbon on Si” instead of “Si on carbon”). The nano-porosity of the materials absorbed most of volume expansion so the particles (between 3-5 mm) can retain the...

Liquid electrolytes in batteries are typically treated as macroscopically homogeneous ionic transport media despite having a complex chemical composition and atomistic solvation structures, leaving a knowledge gap of the microstructural characteristics. Here, we reveal a unique micelle-like structure in a localized high-concentration electrolyte, i...

The solid–electrolyte interphase (SEI) critically governs the performance of rechargeable batteries. An ideal SEI is expected to be electrically insulative to prevent persistently parasitic reactions between the electrode and the electrolyte and ionically conductive to facilitate Faradaic reactions of the electrode. However, the true nature of the...

With the growing maturity of lithium (Li) ion battery technologies, Li metal battery (LMB) is being revitalized in recent years to achieve high energy density. Great progress has been made in understanding the Li utilization and extending the cycle life of LMBs. However, the study of calendar life of LMBs is still limited, although the calendar lif...

Cost and lithium supply issues supply are compelling reasons to consider sodium batteries as potential alternatives to the better-known lithium-ion analogs for large-scale applications, including vehicles. Sodium-ion batteries have been the most highly developed system, with some commercialized systems demonstrate practical energy levels exceeding...

For the anode-free Lithium (Li) batteries (AFLBs), an uniform/dense Li deposition is ideal to stabilize the interface with a solid electrolyte interface (SEI) layer between copper current collector and liquid electrolyte, and minimize the electrolyte/lithium consumption for long-term cell operation. Unlike in the case of Li-ion or Li-metal battery...

Silicon (Si) has been regarded as one of the most promising anode materials for the next generation lithium-ion batteries (LIBs) with high energy density because it has 10 times higher theoretical specific capacity (4200 mAh/g) than that of graphite. However, severe volume change (~300%) of Si during lithiation and delithiation hinders the practica...

Liquid electrolytes in batteries are typically treated as macroscopically homogeneous ionic transport media despite having complex chemical composition and atomistic solvation structures, leaving a knowledge gap of microstructural characteristics. Here, we reveal a unique micelle-like structure in a localized high-concentration electrolyte (LHCE),...

Recharging battery‐powered electric vehicles (EVs) in a similar timeframe as those used for refueling gas‐powered internal combustion vehicles is highly desirable for rapid penetration of the EV market. It is well known that the electrolyte in a battery plays a critical role in fast‐charging capability of the battery because it determines the rate...

Longevity of Li ion batteries strongly depends on the interaction of transporting Li ions in electrode crystals with defects. However, detailed interactions between the Li ion flux and structural defects in the host crystal remain obscure due to the transient nature of such interactions. Here, by in situ transmission electron microscopy and density...

Solid electrolyte interphase (SEI), a thin layer that dynamically forms between active electrode and electrolyte during battery operation, critically governs the performance of rechargeable batteries1-5. An ideal SEI is expected to be electrically insulative to prevent persistently parasitic reactions between the electrode and the electrolyte, whil...

Lithium (Li) metal batteries (LMBs) are a promising candidate for next generation energy storage systems. Although significant progress has been made in extending their cycle life, their calendar life still remains a challenge. Here we demonstrate that the calendar life of LMBs strongly depends on the surface area of Li metal anodes exposed to the...

A three-dimensionally semi-ordered macroporous air electrode can minimize the blocking of air electrodes and improve performance of metal oxygen batteries.

Sulfurized polyacrylonitrile (SPAN) represents one of the most promising directions for high-energy-density lithium (Li)-sulfur batteries. However, the practical application of Li||SPAN is currently limited by the insufficient chemical/electrochemical stability of electrode/electrolyte interphase (EEI). Here, a pinned EEI layer is designed for stab...

Significant progress has been made toward overcoming fundamental challenges in developing a silicon (Si) anode for lithium-ion batteries (LIBs). However, much less work has been reported on design and failure analysis of these batteries for practical applications. In this work, we analyzed the main factors that affect the performance of a Si anode...

The rapid market penetration of EVs requires batteries with higher energy densities. However, graphite-based lithium-ion batteries (LIBs) has eventually reached their practical limit and an anode with higher specific capacities is required to further improve energy density of LIBs. In this regard, silicon (Si) anode has been pursued as one of the m...

Electrochemical models at different scales and varying levels of complexity have been used in the literature to study the evolution of the anode surface in lithium metal batteries. This includes continuum, mesoscale (phase-field approaches), and multiscale models. ¹⁻⁵ Thermodynamics-based equations have been used to study phase changes in lithium b...

Development of Li metal batteries (LMBs) has attracted worldwide attention in recent years due to their much higher theoretical energy densities than those of conventional Li ion batteries. LMBs with high energy density and long cycle life have been demonstrated by several institutions and companies recently. 1,2 LMBs may be safe in their early sta...

Silicon (Si) has been regarded as one of the most promising anode materials for the next generation LIBs with high energy density because it has 10 times higher theoretical specific capacity (4200 mAh/g) than that of graphite. However, severe volume change (~300%) of Si during lithiation and delithiation hinders the practical application of Si anod...

The practical application of lithium (Li) metal anode (LMA) is still hindered by non‐uniformity of solid electrolyte interphase (SEI), formation of “dead” Li, and continuous consumption of electrolyte although LMA has an ultrahigh theoretical specific capacity and a very low electrochemical redox potential. Herein, a facile protection strategy is r...

Electrochemical models at different scales and varying levels of complexity have been used to study the evolution of the anode surface in lithium metal batteries. This includes continuum, mesoscale (phase-field approaches), and multiscale models. Thermodynamics-based equations have been used to study phase changes in lithium batteries using phase-f...

Developing advanced electrolytes is critical for stabilizing electrode/electrolyte interfacial reactions and thus extending cycling stability of sodium (Na) batteries, especially when a high‐voltage cathode (such as NaNi0.68Mn0.22Co0.10O2 (NaNMC)) is used to achieve high energy density in batteries. Here, an advanced electrolyte based on sodium bis...

Sodium-ion batteries (NIBs) have attracted worldwide attention for next-generation energy storage systems. However, the severe instability of the solid–electrolyte interphase (SEI) formed during repeated cycling hinders the development of NIBs. In particular, the SEI dissolution in NIBs with a high-voltage cathode is more severe than in the case of...

Ever increasing need for electrical vehicles (EVs) continually pushes the boundary of high-density energy storage systems. To date, the state of the art of lithium (Li) ion batteries (LIBs) consisting of graphite anode and high voltage Li intercalation cathodes cannot satisfy the energy demand from these applications. By replacing graphite anode wi...

Sodium metal is a promising anode for batteries because of its high theoretical specific capacity (1165 mAh g ⁻¹ ) and great abundance and low cost. However, fundamental issues such as dendrite formation, “dead sodium” accumulation during cycling, fast SEI dissolution or continuous SEI growth bring challenges for stabilizing reversibility of sodium...

Electrochemical models at different scales and varying levels of complexity have been used in theliterature to study the evolution of the anode surface in lithium metal batteries. This includescontinuum, mesoscale (phase-field approaches), and multiscale models. Thermodynamics-basedequations have been used to study phase changes in lithium batterie...

Solid-state sodium (Na) batteries have received extensive attention as a promising alternative to room-temperature liquid electrolyte Na-ion batteries and high-temperature liquid electrode Na–S batteries because of safety concerns. However, the major issues for solid-state Na batteries are a high interfacial resistance between solid electrolytes an...

Solid-electrolyte interphases is essential for stable cycling of rechargeable batteries. The traditional approach for interphase design follows the decomposition of additives prior to the host electrolyte, which, as governed by the thermodynamic rule, however, inherently limits the viable additives. Here we report an alternative approach of using a...

Practical use of lithium (Li) metal for high–energy density lithium metal batteries has been prevented by the continuous formation of Li dendrites, electrochemically isolated Li metal, and the irreversible formation of solid electrolyte interphases (SEIs). Differentiating and quantifying these inactive Li species are key to understand the failure m...

The solid–electrolyte interphase (SEI), a layer formed on the electrode surface, is essential for electrochemical reactions in batteries and critically governs the battery stability. Active materials, especially those with extremely high energy density, such as silicon (Si), often inevitably undergo a large volume swing upon ion insertion and extra...

Porous silicon (Si)/carbon nanocomposites have been extensively explored as a promising anode material for high-energy lithium (Li)-ion batteries (LIBs). However, shrinking of the pores and sintering of Si in the nanoporous structure during fabrication often diminishes the full benefits of nanoporous Si. Herein, a scalable method is reported to pre...

The rechargeable lithium metal battery has attracted wide attention as a next-generation energy storage technology. However, simultaneously achieving high cell-level energy density and long cycle life in realistic batteries is still a great challenge. Here we investigate the degradation mechanisms of Li || LiNi0.6Mn0.2Co0.2O2 pouch cells and presen...

The lithium (Li) metal polymer battery (LMPB) is a promising candidate for solid-state batteries with high safety. However, high voltage stability of such a battery has been hindered by the use of polyethylene oxide (PEO), which oxidizes at a potential lower than 4 V versus Li. Herein, we adopt the polymer-in-salt electrolyte (PISE) strategy to cir...

Lithium (Li)‐magnesium (Mg) alloy with limited Mg amount, which can also be called Mg‐doped Li (Li‐Mg), has been considered as a potential alternative anode for high energy density rechargeable Li metal batteries. However, the optimum doping‐content of Mg in Li‐Mg anode and the mechanism of the improved performance are not well understood. Herein,...

To further improve the energy density of the current lithium ion batteries, tremendous effort has been made on the development of anode materials with higher capacities than the widely commercialized graphite. Lithium metal is considered as the most attractive anode candidate for lithium batteries because of its ultrahigh specific capacity (3860 mA...

Sodium ion battery (NIB) is a very promising technology for the next generation of energy storage systems because of the abundance and low cost of Na in the Earth’s crust. However, the large-scale application of NIBs is still a challenge because of limited cycle life and potential safety concerns. In this regard, electrolyte plays a critical role i...

High-voltage lithium (Li) metal batteries (LMBs) have been revived in recent years due to their high energy density. ¹ However, their practical application is still hindered by the poor stability of the Li metal anode (LMA). The electrolyte is critical to the stability of LMA and the performance of LMBs, because the electrolyte formulation and stru...

Although significant progress has been made in increasing the specific energy and cycle life of silicon (Si) based Li-ion batteries (Si-LIBs), calendar life of these batteries is still less than two years, which is far less than the 10 year life-time required for electrical vehicle applications. ¹ Graphite anodes undergo only ~10% volume change dur...

Rechargeable lithium-oxygen batteries (LOBs) has being considered as one of the most promising candidates for the next-generation high energy-density batteries. The long-term cycling ability of LOBs is closely related to the stability of Li metal anode in an oxygen-rich environment. In this study, a polymer-supported solid electrolyte interphase (P...

The long-range electrical vehicles need the stable and safe high energy cathode materials for next generation batteries. High energy Ni-rich cathode plays a key role in advanced Li-ion batteries, but it suffers from moisture sensitivity, side reactions and gas generation, especially when Ni content increases to more than 0.6. Single crystalline Ni-...

To achieve batteries with high specific energy, long cycle life and low cost, the promising approach is to use lithium (Li) metal as anode and nickel (Ni)-rich/cobalt (Co)-less layered oxides as cathode. When the Ni content in the cathode is increased to an ultrahigh level (Ni ≥ 0.9), more specific energy can be obtained from the capacity contribut...

To improve the energy density of conventional lithium ion batteries (LIBs), Si anode has been extensively investigated as a high-capacity alternative for carbonaceous anodes. However, large (~300%) volume change of Si anode during cycling and its continuous side reactions with electrolyte significantly limit the application of Si anodes. Herein, we...

The ultralow negative electrochemical potential of -3.040 V versus standard hydrogen electrode, extremely high theoretical specific capacity of 3860 mAh g ⁻¹ , and low gravimetric density of 0.534 g cm ⁻³ make lithium (Li) metal has re-emerged as an ideal choice as anode material. However, the aggressive dendritic growth of Li metal during cycling...

Mg-doped Li with about 5 wt. % Mg (Li-Mg5) has the lowest absorption-energy of Li from density functional theory calculations. Experimental tests demonstrate that Li-Mg5 exhibits superior cycling stability to pure Li and Li-Mg10 anodes in Li metal batteries with high-loading cathode and lean electrolyte under 4.4 V high-voltage, leading to dense an...

Rechargeable lithium (Li)-metal batteries have great potential for high energy and low cost, but poor Li anode stability remains a challenge. Carbon host structures have been widely studied; however, our understanding of the key factors determining the performance of such materials is poor, and these limitations have significantly affected the prog...

Significance Lithium (Li) metal battery (LMB) is a very promising candidate for the next-generation high-energy-density batteries. However, its practical applications have been impeded by the instability of metallic Li in the state-of-the-art carbonate electrolytes. Localized high-concentration electrolytes (LHCEs) shed light for practical use of L...

An ever-increasing market for electric vehicles (EVs), electronic devices and others has brought tremendous attention on the need for high energy density batteries with reliable electrochemical performances. However, even the successfully commercialized lithium (Li)-ion batteries still face significant challenges with respect to cost and safety iss...

Rechargeable lithium (Li) metal batteries (LMBs) with ultrahigh-nickel (Ni) layered oxide cathodes offer a great opportunity for applications in electrical vehicles. However, increasing Ni content inherently arouses a tradeoff between specific capacity and electrochemical cyclability due to the aggressive side reactions with electrolyte contributed...

The conventional LiPF6/carbonate-based electrolytes have been widely used in graphite (Gr)-based lithium (Li) ion batteries (LIBs) for more than 30 years because a stable solid electrolyte interphase (SEI) layer forms on the graphite surface and enables its long-term cycling stability. However, few of these electrolytes are stable under the more st...

A silicon (Si) anode is a high-capacity alternative for carbonaceous anodes in lithium ion batteries. However, a large volume change during cycling and continuous side reactions with the electrolyte significantly limit its applications. We designed a localized high-concentration electrolyte using 1H,1H,5H-octafluoropentyl 1,1,2,2-tetrafluoroethyl e...

Li ⁺ ions jump between aggregated networks where Li–O interactions dominate via diluent-enriched phases.

In lithium (Li)-ion batteries (LIBs) and Li metal batteries (LMBs), electrolytes are not only responsible for conducting ions between the positive and negative electrodes, but also for forming effective electrode/electrolyte interphases, which determine the electrochemical performance and aging behavior of LIBs and LMBs. In LMBs, the electrolyte is...