Lithium (Li) metal is an ideal anode material for rechargeable batteries due to its extremely high theoretical specific capacity (3860 mA h g−1), low density (0.59 g cm−3) and the lowest negative electrochemical potential (−3.040 V vs. the standard hydrogen electrode). Unfortunately, uncontrollable dendritic Li growth and limited Coulombic efficiency during Li deposition/stripping inherent in these batteries have prevented their practical applications over the past 40 years. With the emergence of post-Li-ion batteries, safe and efficient operation of Li metal anodes has become an enabling technology which may determine the fate of several promising candidates for the next generation energy storage systems, including rechargeable Li–air batteries, Li–S batteries, and Li metal batteries which utilize intercalation compounds as cathodes. In this paper, various factors that affect the morphology and Coulombic efficiency of Li metal anodes have been analyzed. Technologies utilized to characterize the morphology of Li deposition and the results obtained by modelling of Li dendrite growth have also been reviewed. Finally, recent development and urgent need in this field are discussed.

Lithium metal anodes for rechargeable batteries

Metal Oxides and Oxysalts as Anode Materials for Li Ion Batteries

A review of the features and analyses of the solid electrolyte interphase in Li-ion batteries

Despite the imminent commercial introduction of Li-ion batteries in electric drive vehicles and their proposed use as enablers of smart grids based on renewable energy technologies, an intensive quest for new electrode materials that bring about improvements in energy density, cycle life, cost, and safety is still underway. This Progress Report highlights the recent developments and the future prospects of the use of phases that react through conversion reactions as both positive and negative electrode materials in Li-ion batteries. By moving beyond classical intercalation reactions, a variety of low cost compounds with gravimetric specific capacities that are two-to-five times larger than those attained with currently used materials, such as graphite and LiCoO(2), can be achieved. Nonetheless, several factors currently handicap the applicability of electrode materials entailing conversion reactions. These factors, together with the scientific breakthroughs that are necessary to fully assess the practicality of this concept, are reviewed in this report.

Beyond Intercalation-Based Li-Ion Batteries: The State of the Art and Challenges of Electrode Materials Reacting Through Conversion Reactions

State-of-the-art lithium (Li)-ion batteries are approaching their specific energy limits yet are challenged by the ever-increasing demand of today’s energy storage and power applications, especially for electric vehicles. Li metal is considered an ultimate anode material for future high-energy rechargeable batteries when combined with existing or emerging high-capacity cathode materials. However, much current research focuses on the battery materials level, and there have been very few accounts of cell design principles. Here we discuss crucial conditions needed to achieve a specific energy higher than 350 Wh kg−1, up to 500 Wh kg−1, for rechargeable Li metal batteries using high-nickel-content lithium nickel manganese cobalt oxides as cathode materials. We also provide an analysis of key factors such as cathode loading, electrolyte amount and Li foil thickness that impact the cell-level cycle life. Furthermore, we identify several important strategies to reduce electrolyte-Li reaction, protect Li surfaces and stabilize anode architectures for long-cycling high-specific-energy cells. Jun Liu and Battery500 Consortium colleagues contemplate the way forward towards high-energy and long-cycling practical batteries.

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Pathways for practical high-energy long-cycling lithium metal batteries

In situ Scanning Electron Microscopy (SEM) observation of interfaces within plastic lithium batteries

As an attempt to understand better how cobalt hydroxide additives improve the nickel electrode performance, the Co(OH){sub 2}/CoOOH redox system has been investigated through electrochemical cycling starting from a commercial Co(OH){sub 2} sample. A study of the influence of texture and morphology as well as cycling parameters was performed. For charge rates greater than C/5, relative to the amount of Co(OH){sub 2}, the electrochemical oxidation was found to be a solid-state process. The process led to a nonstoichiometric Co{sub x}{sup 4+}Co{sub 1{minus}x}{sup 3+}OOH{sub 1{minus}x} phase having a mosaic texture with enhanced electronic conductivity due to the presence of Co{sup 4+} ions. For lower charge rates (C/100), the reaction rate is slower, and Co{sup 2+} can dissolve in the electrolyte, leading to a less conductive phase having a stoichiometric composition (CoOOH) and a monolithic texture. When present, the Co{sup 4+} ions are reduced to Co{sup 3+}, at 1.05 V while other reductions Co{sup 3+} {yields} Co{sup 2+} and Co{sup 2+} {yields} Co{degree} take place at a lower potential, 0.67 and 0.0 V, respectively. These two reactions are both associated with a dissolution of Co(II) species, followed by a migration of cobalt toward the current collector, with the overall result being anmore » electrode degradation.« less

https://iopscience.iop.org/article/10.1149/1.1393355/pdf

Electrochemical Behavior of Cobalt Hydroxide Used as Additive in the Nickel Hydroxide Electrode

Electrochemical study of nanometer Co3O4, Co, CoSb3 and Sb thin films toward lithium

In situ TEM study of the interface carbon/electrolyte

This paper details the reacting paths involved during the oxidation of αII-Ni(OH)2 and βII-Ni(OH)2 with ozone, which is compared to the oxidation process conducted in aqueous solution. The main advantage of the ozone method lies in the control of the reaction medium steps owing to the feasibility of operating in the presence or absence of alkaline cations. This enables the preparation of the pure βIII-NiOOH phase, well-known to be difficult to obtain in aqueous media without γIII-NiOOH traces. The reaction mechanisms for both oxidation processes were found to be similar, and to yield the same final products, except for αII-Ni(OH)2, where ozonation allowed the preparation of a new oxidized phase that was isolated and characterized by means of complementary techniques such as X-ray diffraction, chemical analysis, HRTEM, TGA, and FT-IR. A mechanism to account for the formation of this phase is proposed.

B. Beaudoin

Papers

In situ Scanning Electron Microscopy (SEM) observation of interfaces within plastic lithium batteries

Electrochemical Behavior of Cobalt Hydroxide Used as Additive in the Nickel Hydroxide Electrode

Electrochemical study of nanometer Co3O4, Co, CoSb3 and Sb thin films toward lithium

In situ TEM study of the interface carbon/electrolyte

Ozonation: A unique route to prepare nickel oxyhydroxides. Synthesis optimization and reaction mechanism study