Lithium batteries: Status, prospects and future

Lithium-ion batteries have had a profound impact on our daily life, but inherent limitations make it difficult for Li-ion chemistries to meet the growing demands for portable electronics, electric vehicles and grid-scale energy storage. Therefore, chemistries beyond Li-ion are currently being investigated and need to be made viable for commercial applications. The use of metallic Li is one of the most favoured choices for next-generation Li batteries, especially Li-S and Li-air systems. After falling into oblivion for several decades because of safety concerns, metallic Li is now ready for a revival, thanks to the development of investigative tools and nanotechnology-based solutions. In this Review, we first summarize the current understanding on Li anodes, then highlight the recent key progress in materials design and advanced characterization techniques, and finally discuss the opportunities and possible directions for future development of Li anodes in applications.

Reviving the lithium metal anode for high-energy batteries

Since the discovery of mechanically exfoliated graphene in 2004, research on ultrathin two-dimensional (2D) nanomaterials has grown exponentially in the fields of condensed matter physics, material science, chemistry, and nanotechnology. Highlighting their compelling physical, chemical, electronic, and optical properties, as well as their various potential applications, in this Review, we summarize the state-of-art progress on the ultrathin 2D nanomaterials with a particular emphasis on their recent advances. First, we introduce the unique advances on ultrathin 2D nanomaterials, followed by the description of their composition and crystal structures. The assortments of their synthetic methods are then summarized, including insights on their advantages and limitations, alongside some recommendations on suitable characterization techniques. We also discuss in detail the utilization of these ultrathin 2D nanomaterials for wide ranges of potential applications among the electronics/optoelectronics, electrocat...

Recent Advances in Ultrathin Two-Dimensional Nanomaterials

Electrolytes and interphases in Li-ion batteries and beyond.

Batteries are a key technology in modern society. They are used to power electric and hybrid electric vehicles and to store wind and solar energy in smart grids. Electrochemical devices with high energy and power densities can currently be powered only by batteries with organic liquid electrolytes. However, such batteries require relatively stringent safety precautions, making large-scale systems very complicated and expensive. The application of solid electrolytes is currently limited because they attain practically useful conductivities (10(-2) S cm(-1)) only at 50-80 °C, which is one order of magnitude lower than those of organic liquid electrolytes. Here, we report a lithium superionic conductor, Li(10)GeP(2)S(12) that has a new three-dimensional framework structure. It exhibits an extremely high lithium ionic conductivity of 12 mS cm(-1) at room temperature. This represents the highest conductivity achieved in a solid electrolyte, exceeding even those of liquid organic electrolytes. This new solid-state battery electrolyte has many advantages in terms of device fabrication (facile shaping, patterning and integration), stability (non-volatile), safety (non-explosive) and excellent electrochemical properties (high conductivity and wide potential window).

A lithium superionic conductor

High ionic conductivity in lithium lanthanum titanate

Lithium ion rechargeable batteries are used as the power supply of cellular phones and several other portable electrical devices at present, and demand appears to increase exponentially. The concern about energy sources in the near future, either for electric vehicles (EV) or for large-scale batteries for electricity power storage, has made lithium ion rechargeable battery development into a growth area which has gained high momentum for its research activities. Here, while presenting the state of the art of lithium ion battery technology, the current research into materials, which constitute anode, electrolyte and cathode is described and the underlying problems associated with their development, advantages and drawbacks is analyzed. Both polymer electrolytes, which is a recent topic, as well as conventional organic liquids electrolyte, are also described.

Recent developments in lithium ion batteries

To improve the cycle performance of spinel LiMn{sub 2}O{sub 4} as the cathode of 4 V class lithium secondary batteries, the quaternary spinel phases LiM{sub y}Mn{sub 2{minus}y}O{sub 4} (M = Co, Cr, Ni; y = 1/12, 1/9, 1/6, 1/3) were prepared at 750 C in air. X-ray diffraction and electrochemical studies were carried out using the Li{vert_bar}Li{sub x}M{sub y}Mn{sub 2{minus}y}O{sub 4} cells. These cathodes were more tolerant to repeated lithium extraction and insertion than a standard LiMn{sub 2}O{sub 4} spinel electrode in spite of a small reduction in the initial capacity. Considering both cycle life and capacity density, LiCo{sub 1/6}Mn{sub 11/6}O{sub 4} showed good cycle performance with an energy density of 370 Wh/kg at the 300th cycle. The improvement in cycling performance is attributed to the stabilization in the spinel structure by the doped metal cations.

Masataka Wakihara

Papers

High ionic conductivity in lithium lanthanum titanate

Recent developments in lithium ion batteries

The Spinel Phases LiM y Mn2 − y O 4 (M = Co, Cr, Ni) as the Cathode for Rechargeable Lithium Batteries

Solid State Ionics for Batteries

Particle morphology and electrochemical performances of spinel LiMn2O4 powders synthesized using ultrasonic spray pyrolysis method