Synergetic regulation of SEI mechanics and crystallographic orientation for stable lithium metal pouch cells.

The advancement of Li-metal batteries is significantly impeded by the presence of unstable solid electrolyte interphase and Li dendrites upon cycling. Herein, we present an innovative approach to address these issues through the synergetic regulation of solid electrolyte interphase mechanics and Li crystallography using yttrium fluoride/polymethyl methacrylate composite layer. Specifically, we demonstrate the in-situ generation of Y-doped lithium metal through the reaction of composite layer with Li metal, which reduces the surface energy of the (200) plane, and tunes the preferential crystallographic orientation to (200) plane from conventional (110) plane during Li plating. These changes effectively passivate Li metal, thereby significantly reducing undesired side reactions between Li and electrolytes by 4 times. Meanwhile, the composite layer with suitable modulus (~1.02 GPa) can enhance mechanical stability and maintain structural stability of SEI. Consequently, a 4.2 Ah pouch cell with high energy density of 468 Wh kg-1 and remarkable capacity stability of 0.08% decay/cycle is demonstrated under harsh condition, such as high-areal-capacity cathode (6 mAh cm-2), lean electrolyte (1.98 g Ah-1), and high current density (3 mA cm-2). Our findings highlight the potential of reactive composite layer as a promising strategy for the development of stable Li-metal batteries.

Size Limiting Elemental Ferroelectricity in Bi Nanoribbons: Observation, Mechanism, and Opportunity.

Combined with the inherent spin-orbital coupling effect, the elemental ferroelectricity of monolayer Bi (bismuthene) is the critical property that renders this system a 2D ferroelectric topological insulator. Here, using first-principles calculations, we systematically investigate the ferroelectric polarization in bismuthene nanoribbons and discover the width size limiting effect arising from the edge effects. The decreasing width led to the spontaneous transformation of the zigzag (ZZ) and armchair (AC) paired Bi nanoribbons into newly discovered high-symmetric nonpolarized nanoribbons. For ZZ-paired nanoribbons, the driving force of the phase transition is attributed to the depolarization field, similar to the conventional perovskite ferroelectric thin films. Instead, edge stress as a novel mechanism played a major role in the phase transition of AC-paired nanoribbons. Inspired by such a revealed mechanism, the phase transition and related ultrahigh piezoelectricity can be achieved by strain engineering in Bi nanoribbons, which could enable new applications for 2D ferroelectric devices.

Enabling 420 Wh kg-1 Stable Lithium-Metal Pouch Cells by Lanthanum Doping.

Lithium (Li) metal, a promising anode for high-energy-density rechargeable batteries, typically grows along the low-surface energy (110) plane in the plating process, resulting in uncontrollable dendrite growth and unstable interface. Herein, an unexpected Li growth behavior by lanthanum (La) doping is reported: the preferred orientation turns to (200) from (110) plane, enabling 2D nuclei rather than the usual 1D nuclei upon Li deposition and thus forming a dense and dendrite-free morphology even at an ultrahigh areal capacity of 10 mAh cm-2 . Noticeably, La doping further decreases the reactivity of Li metal toward electrolytes, thereby establishing a stable interface. The dendrite-free, stable Li anode enables a high average Coulombic efficiency of 99.30% at 8 mAh cm-2 for asymmetric Li||LaF3 -Cu cells. A 3.1 Ah LaF3 -Li||LiNi0.8 Co0.1 Mn0.1 O2 pouch cell at a high energy density (425.73 Wh kg-1 ) with impressive cycling stability (0.0989% decay per cycle) under lean electrolyte (1.76 g Ah-1 ) and high cathode loading (5.77 mAh cm-2 ) using this doped Li anode is further demonstrated.

Angiotensin-converting enzyme insertion/deletion gene polymorphisms associated with risk of atrial fibrillation: A meta-analysis of 23 case-control studies.

AIMS: The renin-angiotensin-aldosterone system is important to the development of atrial fibrillation (AF). A lot of research has focused on the relationship between angiotensin-converting enzyme (ACE) insertion (I) /deletion (D) gene polymorphisms and AF, with inconsistent results. A meta-analysis was carried out to find the correlation between ACE I/D gene polymorphisms and AF. METHODS: Data were extracted from articles published before September 2013 on ACE I/D polymorphisms and AF in Embase, PubMed, WanFangData, and China National Knowledge Infrastructure. RESULTS: The recessive model found that ACE I/D gene polymorphisms were related to AF (odds ratio (OR) = 1.61, 95% confidence interval (CI) = 1.16-1.72). Subgroup analysis showed a significant association in the recessive model for Asian (OR = 1.40, 95% CI = 1.19-1.80) and Caucasian (OR = 1.42, 95% CI = 1.01-1.99) populations. CONCLUSIONS: ACE I/D gene polymorphisms and AF are significantly related to ethnicity. Individuals with the ACE D/D genotype appear to be at higher risk of AF.