Hydrides as High Capacity Anodes in Lithium Cells: An Italian “Futuro in Ricerca di Base FIRB-2010” Project

Abstract

Automotive and stationary energy storage are among the most recently-proposed and still unfulfilled applications for lithium ion devices. Higher energy, power and superior safety standards, well beyond the present state of the art, are actually required to extend the Li-ion battery market to these challenging fields, but such a goal can only be achieved by the development of new materials with improved performances. Focusing on the negative electrode materials, alloying and conversion chemistries have been widely explored in the last decade to circumvent the main weakness of the intercalation processes: the limitation in capacity to one or at most two lithium atoms per host formula unit. Among all of the many proposed conversion chemistries, hydrides have been proposed and investigated since 2008. In lithium cells, these materials undergo a conversion reaction that gives metallic nanoparticles surrounded by an amorphous matrix of LiH. Among all of the reported conversion materials, hydrides have outstanding theoretical properties and have been only marginally explored, thus making this class of materials an interesting playground for both fundamental and applied research. In this review, we illustrate the most relevant results achieved in the frame of the Italian National Research Project FIRB 2010 Futuro in Ricerca "Hydrides as high capacity anodes in lithium cells" and possible future perspectives of research for this class of materials in electrochemical energy storage devices.

Rational Design of Nanosized Light Elements for Hydrogen Storage: Classes, Synthesis, Characterization, and Properties

“…[279a] MgH 2 nanoparticles of 2-5 nm supported on superP carbon showed promising performance in Li cells regarding the reversible capacity and cycling ability. [280]…”

The Status of Representative Anode Materials for Lithium‐Ion Batteries

“…In addition, inherent defects in the materials themselves (such as the lithium dendrites on the surface of carbonaceous materials and the poor electrical conductivity and energy density of titanium dioxide and lithium titanate) are also challenges that need to be overcome. [44][45][46] Materials with an alloying reaction mechanism mainly refer to tin-based and silicon-based alloys and compounds, which usually have an ultra-high theoretical capacity. Nevertheless, the violent volume change during charge/discharge leading to the destruction of the material structure has always troubled researchers.…”

“…Intercalation anodes (carbon‐based materials, titanium dioxide, and lithium titanate) usually show a low theoretical capacity because of limitations in the quantity of embedded lithium. In addition, inherent defects in the materials themselves (such as the lithium dendrites on the surface of carbonaceous materials and the poor electrical conductivity and energy density of titanium dioxide and lithium titanate) are also challenges that need to be overcome [44–46] . Materials with an alloying reaction mechanism mainly refer to tin‐based and silicon‐based alloys and compounds, which usually have an ultra‐high theoretical capacity.…”

TiF3 catalyzed MgH2 as a Li/Na ion battery anode

“…%) and low cost [1,2]. It was introduced as a conversion anode material for reversible electrochemical Li ion uptake in 2008 [3], and has attracted growing research interest since then due to its high capacity for Li ion storage and cost-effectiveness [4][5][6][7][8]. Its lithiation undergoes dehydrogenation of MgH2 with the formation of LiH (Reaction 1) resulting in a Li ion storage capacity of 2038 mAh g -1 , which is defined as the theoretical capacity.…”