No abstract

h i g h l i g h t sChemistry and electrochemistry in lithium-based microbatteries. Recent concept and cell design towards different applications. Future perspectives of microbattery development. a b s t r a c tBatteries employing lithium chemistry have been intensively investigated because of their high energy attributes which may be deployed for vehicle electrification and large-scale energy storage applications. Another important direction of battery research for micro-electronics, however, is relatively less discussed in the field but growing fast in recent years. This paper reviews chemistry and electrochemistry in different microbatteries along with their cell designs to meet the goals of their various applications. The state-of-the-art knowledge and recent progress of microbatteries for emerging micro-electronic devices may shed light on the future development of microbatteries towards high energy density and flexible design.

Some of the best thermoelectrics are complex materials with rattling guests inside oversized atomic cages. Understanding the chemical and structural origins of the rattling behavior is essential to the design of thermoelectric materials. In this work, a clear connection is established between the local bonding asymmetry and anharmonic rattling modes in tetrahedrite thermoelectrics, enabled by the chemically active electron lone pairs. The studies reveal a fi ve-atom atomic cage Sb[CuS 3 ]Sb in Cu 12 Sb 4 S 13 tetrahedrites that exhibits strong local bonding asymmetry: covalent bonding inside the CuS 3 trigonal plane and weak out-of-plane bonding induced by the lone-pair electrons of Sb. This bonding asymmetry leads to out-of-plane rattling modes that are quasilocalized and anharmonic with low frequency and large amplitude, and are likely the origin of low thermal conductivity in tetrahedrites. Such knowledge highlights the importance of local structure asymmetry and lonepair atoms in driving anharmonic rattling, providing a stepping stone to the discovery and design of next-generation thermoelectrics.

No abstract

Crystalline Li7P3S11 is a promising solid electrolyte for all solid-state lithium/lithium ion batteries. A controllable liquid phase synthesis of Li7P3S11 is more desirable than conventional mechanochemical synthesis, but recent attempts suffer from reduced ionic conductivities. Here we elucidate the mechanism of formation of crystalline Li7P3S11 synthesized in the liquid phase [acetonitrile (ACN)]. We conclude that crystalline Li7P3S11 forms through a two-step reaction: (1) formation of solid Li3PS4·ACN and amorphous “Li2S·P2S5” phases in the liquid phase and (2) solid-state conversion of the two phases. The implication of this two-step reaction mechanism for morphology control and the transport properties of liquid phase synthesized Li7P3S11 is identified and discussed.