Bruno Scrosati

An advanced lithium ion battery based on high performance electrode materials.

In this paper we report the study of a high capacity Sn-C nanostructured anode and of a high rate, high voltage Li[Ni(0.45)Co(0.1)Mn(1.45)]O(4) spinel cathode. We have combined these anode and cathode materials in an advanced lithium ion battery that, by exploiting this new chemistry, offers excellent performances in terms of cycling life, i.e., ca. 100 high rate cycles, of rate capability, operating at 5C and still keeping more than 85% of the initial capacity, and of energy density, expected to be of the order of 170 Wh kg(-1). These unique features make the battery a very promising energy storage for powering low or zero emission HEV or EV vehicles.

Impedance Spectroscopy Study of PEO‐Based Nanocomposite Polymer Electrolytes

The addition of nanometric fillers (e.g., , ) to polymer electrolytes induces consistent improvement in the transport properties. The increase in conductivity and in the cation transference number is attributed to the enhancement of the degree of the amorphous phase in the polymer matrix, as well as to some acid‐base Lewis type, ceramic‐electrolyte interactions. This model is confirmed by results obtained from a detailed impedance spectroscopy study carried out on poly(ethylene oxide) [P(EO)]‐based polymer electrolyte samples with and without ceramic fillers.

An advanced lithium-ion battery based on a graphene anode and a lithium iron phosphate cathode.

We report an advanced lithium-ion battery based on a graphene ink anode and a lithium iron phosphate cathode. By carefully balancing the cell composition and suppressing the initial irreversible capacity of the anode in the round of few cycles, we demonstrate an optimal battery performance in terms of specific capacity, that is, 165 mAhg(-1), of an estimated energy density of about 190 Wh kg(-1) and a stable operation for over 80 charge-discharge cycles. The components of the battery are low cost and potentially scalable. To the best of our knowledge, complete, graphene-based, lithium ion batteries having performances comparable with those offered by the present technology are rarely reported; hence, we believe that the results disclosed in this work may open up new opportunities for exploiting graphene in the lithium-ion battery science and development.

The Interfacial Stability of Li with Two New Solvent‐Free Ionic Liquids: 1,2‐Dimethyl‐3‐propylimidazolium Imide and Methide

The room temperature stability of the Li interface in the presence of 1,2-dimethyl-3-propylimidazolium imide and methide was followed by electrochemical impedance spectroscopy for a period of 112 days. We found that while Li foil initially reacted with both ionic liquids, the interfacial film on Li formed in the imide-based electrolyte stabilized at an interfacial resistance of 1.5 kΩ cm 2 , while that for the methide-based electrolyte rose to an interfacial resistance value exceeding 50 kΩ cm 2 .

Energy Storage Materials Synthesized from Ionic Liquids

The advent of ionic liquids (ILs) as eco-friendly and promising reaction media has opened new frontiers in the field of electrochemical energy storage. Beyond their use as electrolyte components in batteries and supercapacitors, ILs have unique properties that make them suitable as functional advanced materials, media for materials production, and components for preparing highly engineered functional products. Aiming at offering an in-depth review on the newly emerging IL-based green synthesis processes of energy storage materials, this Review provides an overview of the role of ILs in the synthesis of materials for batteries, supercapacitors, and green electrode processing. It is expected that this Review will assess the status quo of the research field and thereby stimulate new thoughts and ideas on the emerging challenges and opportunities of IL-based syntheses of energy materials.

An Advanced Lithium-Air Battery Exploiting an Ionic Liquid-Based Electrolyte

A novel lithium-oxygen battery exploiting PYR14TFSI-LiTFSI as ionic liquid-based electrolyte medium is reported. The Li/PYR14TFSI-LiTFSI/O2 battery was fully characterized by electrochemical impedance spectroscopy, capacity-limited cycling, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The results of this extensive study demonstrate that this new Li/O2 cell is characterized by a stable electrode-electrolyte interface and a highly reversible charge-discharge cycling behavior. Most remarkably, the charge process (oxygen oxidation reaction) is characterized by a very low overvoltage, enhancing the energy efficiency to 82%, thus, addressing one of the most critical issues preventing the practical application of lithium-oxygen batteries.

Highly Cyclable Lithium-Sulfur Batteries with a Dual-Type Sulfur Cathode and a Lithiated Si/SiOx Nanosphere Anode.

Lithium-sulfur batteries could become an excellent alternative to replace the currently used lithium-ion batteries due to their higher energy density and lower production cost; however, commercialization of lithium-sulfur batteries has so far been limited due to the cyclability problems associated with both the sulfur cathode and the lithium-metal anode. Herein, we demonstrate a highly reliable lithium-sulfur battery showing cycle performance comparable to that of lithium-ion batteries; our design uses a highly reversible dual-type sulfur cathode (solid sulfur electrode and polysulfide catholyte) and a lithiated Si/SiOx nanosphere anode. Our lithium-sulfur cell shows superior battery performance in terms of high specific capacity, excellent charge-discharge efficiency, and remarkable cycle life, delivering a specific capacity of ∼750 mAh g(-1) over 500 cycles (85% of the initial capacity). These promising behaviors may arise from a synergistic effect of the enhanced electrochemical performance of the newly designed anode and the optimized layout of the cathode.

Double-structured LiMn(0.85)Fe(0.15)PO4 coordinated with LiFePO4 for rechargeable lithium batteries.

Olivine-type LiFePO4, discovered by Goodenough and coworkers, has been extensively studied owing to its low costs, environmental friendliness, and in particular, superior thermal stability at the deeply charged state. Use of a carbon coating significantly improved the intrinsic poor electric conductivity, to around 10 1 Scm 1 from around 10 8 Scm 1 at room temperature, and therefore, this material has undergone intensive investigation for large-scale lithium battery applications. LiMnPO4, which is an isomorph of LiFePO4, is a more promising electrode material than LiFePO4 as a result of its higher operation voltage (4.1 V vs. Li/Li). However, LiMnPO4 also suffers from poor electronic conductivity (< 10 10 Scm ) and cycle life because of Mn dissolution, like a Mn spinel. High energy density is required for midto large-scale batteries because the mounting spaces are quite small for vehicles and other energy storage applications. This constraint necessitates use of micron-sized particles to yield high volumetric energy density and reliable battery performance. The few published works that have dealt with micron-sized LiMnPO4 compounds have indicated that the resulting electrochemical properties still need to be improved. We predict that substantial improvement could be overcome by applying a thick and uniform olivine LiFePO4 layer onto micron-sized spherical LiMn0.85Fe0.15PO4 to enhance the cycle life and rate capability (see Scheme 1). Figure S1a in the Supporting Information shows a schematic drawing of the steps involved in the fabrication of micron-sized LiMn0.85Fe0.15PO4 followed by LiFePO4 surface modification.

Challenges and prospects of the role of solid electrolytes in the revitalization of lithium metal batteries

The scientific community is continuously committed to the search for new high energy electrochemical storage devices. In this regard, lithium metal batteries, due to their very high electrochemical energy storage capacity, appear to be a highly appealing choice. Unfortunately, the use of lithium metal as the anode may lead to some safety hazards due to its uneven deposition upon charging, resulting in dendrite growth and eventual shorting of the battery. This issue may be successfully addressed by using intrinsically safer electrolytes capable of establishing a physical barrier at the electrode interface. The most promising candidates are solid electrolytes, either polymeric or inorganic. The main purpose of this review is to describe the present status of worldwide research on these electrolyte materials together with a critical discussion of their transport properties and compatibility with metallic lithium, hoping to provide some general guidelines for the development of innovative and safe lithium metal batteries.

Ionic liquids as tailored media for the synthesis and processing of energy conversion materials

Though in its infancy stage, ionic liquid (IL)-assisted synthesis and processing of energy conversion materials is triggering a wide interest to eco-friendly production of already existing and novel materials. ILs possess the potential of overcoming the limitations of conventional synthesis approaches. Due to their unique characteristics such as high chemical and thermal stabilities, nearly negligible vapour pressure, wide electrochemical window, broad liquidus range, tunable polarity, hydrophobicity/hydrophilicity, ionic liquids are opening new frontiers in the ionothermal synthesis of tailored materials, enabling products that are difficult or impossible to achieve by using other, more conventional preparation routes. Trying to offer an exhaustive review on the burgeoning role of ionic liquids for the synthesis and processing of energy conversion materials, this perspective article focuses on IL-assisted production of electrode materials and catalysts for fuel cells, photo-induced water splitting and dye-sensitized solar cells. A brief excursion on the use of ionic liquids for the processing of natural fuels for biofuel cells is also made. The state-of-the-art research endeavours are firstly evaluated, followed by the exploration of future research directions with some thoughts on emerging challenges and opportunities.