<i>In Situ</i> Orthogonal Polymerization for Constructing Fast-Charging and Long-Lifespan Li Metal Batteries with Topological Copolymer Electrolytes

Fast-charging Li metal batteries (LMBs) with low cost, high safety, and long lifespan are highly desirable for next-generation energy storage technologies yet have been rarely achieved. Here, we report the in situ fabrication of well-designed blend, block, and bottle-brush solid-state polymer electrolytes (SPEs) integrating poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMA) and poly(trimethylene carbonate) (PTMC) matrices via Li-catalyzed orthogonal polymerization. Among them, the bottle-brush topological SPEs may display quasi-molecular-scale miscibility between PPEGMA and PTMC, maximize the synergistic coordination of Li+ with ether and carbonate units at the PPEGMA/PTMC interface, and simultaneously exhibit ideal mass transport properties and a broad electrochemical stability window. Further incorporating trifluoroethyl methacrylate (TFEMA) into the bottle-brush SPE allows facile construction of a robust solid electrolyte interphase (SEI). These, together with the fast charge transfer kinetics inherited from the in situ polymerization technique, enable the development of the first example of solid-state polymeric LMB capable of operating steadily at 3C (73% capacity retention after 1000 cycles)

Amine-Acrylate Michael Addition: A Versatile Platform for Fabrication of Polymer Electrolytes with Varied Cross-Linked Networks

Compared to the design of polymer electrolytes (PEs) using a strictly controlled copolymerization approach, the cross-linking polymerization method is more flexible and efficient and ensures the film-forming properties of the copolymer with strong mechanical strength. However, conventional cross-linked methods are difficult for structural modulation, thus limiting the further application of PEs in lithium metal batteries (LMBs). Herein, we report the amine-acrylate Michael addition for fabricating PEs with varied cross-linked networks. By adjustment of the molar ratios of the reacting monomers, PEs with different topologies were prepared. Notably, an excess of the amine monomer endowed the polymer electrolyte with a self-healing ability. In addition, the gel polymer electrolyte (GPE) was fabricated by the introduction of a deep eutectic solvent and showed a high ionic conductivity (1.44 × 10–4 S cm–1 at 30 °C), high oxidation voltage (>5.0 V vs Li+/Li), and excellent interface stability with the electrodes. The Li|GPE|Li cell can work for 1000 h at a current density of 0.1 mA cm–2. Moreover, Li|GPE|LiFePO4 cells could be cycled for 200 cycles at 0.5C with a capacity retention rate of 94.3%

Facile Fabrication of Polymer Electrolytes with Branched Structure via Deep Eutectic Electrolyte-Enabled <i>In Situ</i> Polymerizations

The demand for higher energy density in energy storage devices drives further research on lithium metal batteries (LMBs) because of the high theoretical capacity and low voltage of lithium metal anode. Polymer electrolytes (PEs) exhibit obvious advantages in combating volatilization and leakage compared with liquid electrolytes, which improves the safety of LMBs. However, it is still difficult to construct PEs with a stable electrolyte–electrode interface for high-performance and long-term life LMBs. Herein, the gel polymer electrolyte (GPE-SL) containing deep eutectic electrolyte (DEE) and branchlike polymer skeleton are designed and prepared by the DEE-induced in situ cationic and radical polymerizations. The DEE provides a smooth Li+ migration pathway to ensure the electrochemical properties, and the multibrominated polymer matrix formed in situ enables a LiBr-rich solid electrolyte interphase (SEI) layer on lithium metal anode and prolongs the life span of LMBs. Hence, the Li|GPE-SL|LiFePO4 battery displays an excellent cycling stability with 84% capacity retention after 1200 cycles at 1C. This simple deep eutectic electrolyte-induced polymerization method provides a promising direction for high-performance LMBs with improved anode–electrolyte compatibility through the construction of a stable SEI layer in situ

Facile Assembly of C–N Bond-Containing Polymer Electrolytes Enabled by Lithium Salt-Catalyzed Aza-Michael Addition

Assembling polymer electrolytes (PEs) with lithium metal anodes is a promising strategy to address safety and specific capacity concerns. Molecular design on conductive polymer matrices avoids inherent high crystallinity, poor ion transport, and combustion drawbacks by adjusting the chain structure and functional groups. However, conventional structural modulation methods are difficult to conduct via in situ polymerization and cell assembly, thus hampering the further performance enhancement of PEs in lithium batteries. Herein, we report a simple aza-Michael addition method induced by lithium salts for designing and fabricating high-performance PEs. This method fulfills the in situ structure modulation of polyether-based PEs without any introduction of non-electrolytic components. The obtained polyether electrolytes exhibit a more amorphous cross-linked structure, leading to a favorable medium for ion migration and excellent flexibility. In addition, the introduction of C–N bonds imparts excellent non-flammability to the material as well as the ability to interact with sulfolane. Hence, the in situ-constructed gel polymer electrolyte (GPE) is characterized by a high ionic conductivity (1.76 × 10–4 S cm–1 at 30 °C) and excellent interface stability with the electrodes. The assembled Li/LiFePO4 (LFP) battery based on this newly designed GPE exhibits a high initial specific discharge capacity and a good rate performance (112.7 mAh g–1 at 5 C). Long-term stability was also demonstrated, with a capacity retention of 86.8% after 500 cycles at 0.5 C

Facile Assembly of C–N Bond-Containing Polymer Electrolytes Enabled by Lithium Salt-Catalyzed Aza-Michael Addition

Assembling polymer electrolytes (PEs) with lithium metal anodes is a promising strategy to address safety and specific capacity concerns. Molecular design on conductive polymer matrices avoids inherent high crystallinity, poor ion transport, and combustion drawbacks by adjusting the chain structure and functional groups. However, conventional structural modulation methods are difficult to conduct via in situ polymerization and cell assembly, thus hampering the further performance enhancement of PEs in lithium batteries. Herein, we report a simple aza-Michael addition method induced by lithium salts for designing and fabricating high-performance PEs. This method fulfills the in situ structure modulation of polyether-based PEs without any introduction of non-electrolytic components. The obtained polyether electrolytes exhibit a more amorphous cross-linked structure, leading to a favorable medium for ion migration and excellent flexibility. In addition, the introduction of C–N bonds imparts excellent non-flammability to the material as well as the ability to interact with sulfolane. Hence, the in situ-constructed gel polymer electrolyte (GPE) is characterized by a high ionic conductivity (1.76 × 10–4 S cm–1 at 30 °C) and excellent interface stability with the electrodes. The assembled Li/LiFePO4 (LFP) battery based on this newly designed GPE exhibits a high initial specific discharge capacity and a good rate performance (112.7 mAh g–1 at 5 C). Long-term stability was also demonstrated, with a capacity retention of 86.8% after 500 cycles at 0.5 C

Apolipoprotein E Polymorphism and Colorectal Neoplasm: Results from a Meta-Analysis

<div><p>To investigate the relationship of Apolipoprotein E (<i>APOE</i>) gene polymorphism to colorectal neoplasia (CRN), we performed a systematic review and meta-analysis. Eligible studies were identified through a systematic literature review from PubMed, EMBASE, and the Science Citation Index up to February 2014. A combined analysis was performed, followed by a subgroup analyses stratified by the study design. We used data collected from 8 prospective studies involving respectively a total of 9243 participants and 4310 CRN cases which including 438 patients with colorectal adenoma (CRA), and 3873 patients with colorectal carcinoma (CRC). The pooled data from this meta-analysis indicated there was no significant association between <i>APOE</i> polymorphism and CRN (ε2: P = 0.51, OR 1.04 95% CI 0.93 to 1.16; ε4: P = 0.72, OR 0.98 95% CI 0.90 to 1.07). Interestingly, subgroup analysis demonstrated there was a significant decreased risk for proximal CRN in patients with <i>APOE</i> ε4 (P = 0.0007, OR 0.52 95% CI 0.35 to 0.76). Data showed no significant association between <i>APOE</i> genotype and overall CRN. However, compared with those carry APOE ε3 alleles, persons with <i>APOE</i> ε4 genotype have significant decreased risk suffering from proximal CRN but not from distal CRN.</p></div

Comparisons of apolipoprotein E genotype and CRN risk.

<p>Comparisons of apolipoprotein E genotype and CRN risk.</p

Funnel plot of the meta-analysis.

<p>Funnel plot of the meta-analysis.</p

Allele frequencies and percentage of apolipoprotein E polymorphisms carriers among CRN cases and controls.

<p>Allele frequencies and percentage of apolipoprotein E polymorphisms carriers among CRN cases and controls.</p

Forest plots of odds ratio with 95% CI for <i>APOE</i> polymorphism and proximal CRN (A: ε2 versus ε3, B, ε4 versus ε3) and distal CRN risk (C: ε2 versus ε3, D, ε4 versus ε3).

<p>Forest plots of odds ratio with 95% CI for <i>APOE</i> polymorphism and proximal CRN (A: ε2 versus ε3, B, ε4 versus ε3) and distal CRN risk (C: ε2 versus ε3, D, ε4 versus ε3).</p