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The practical application of lithium‐rich layered oxides is prohibited by the drawbacks such as severe capacity and voltage degradation resulting from unstable oxygen redox environment and the accompanied irreversible oxygen release. Herein, a facile and effective strategy is proposed to regulate the oxygen redox chemistry via foreign Fe doping and its induced intrinsic transition metal (TM) doping as well as the in situ constructed spinel surface layer. The Fe doping, together with the induced intrinsic TM dual doping, can stabilize the lattice oxygen in the bulk due to the formed stronger FeO bond, and restrain the irreversible TM migration and then the undesirable phase transformation. More importantly, thermodynamical energy barrier of oxygen activation is dramatically decreased by the O 2p–Fe 3d charge‐transfer, allowing stable oxygen redox activity. And the pre‐constructed spinel layer can effectively stabilize the surface lattice oxygen and suppress harmful interfacial side‐reactions. Such a simple optimizing method make the modified cathode exhibit a high specific capacity of 298 mAh g−1 at 0.2 C, outstanding cycling stability with a superior capacity and voltage retentions of 92.5% and 90.8%, respectively, after 400 cycles at 1 C. This study provides a new direction for developing advanced Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Highly uniformly dense garnet type solid‐state electrolyte plays a significant role in determining the performance of solid‐state lithium batteries. Herein, a rational powder‐covering sintering strategy is proposed and demonstrated, in which narrow‐particle‐size‐distribution fine powder and uniform sintering temperature distribution are considered as very significant factors. It is suggested that powder materials with wider particle size distribution dramatically decrease the densified level of electrolytes. Slow temperature elevating rate and the overhead structure of bearing table are found to be beneficial to uniform densification. Moreover, the uniform densification process of sintering solid‐state electrolyte is studied both microscopically and macroscopically, which can be divided into three phases according to the grain growing evolution and linear shrinkage patterns. The ionic conductivity of the as‐prepared Li6.4La3Zr1.4Ta0.6O12 (LLZTO) garnet electrolyte is determined to be 0.73 mS cm−1 at 303 K with an activation energy of 0.37 eV. The Li/LLZTO/Li symmetric cell exhibits a small interfacial impedance of 8.49 Ω cm2 and a high apparent critical current density of 2.15 mA cm−2 and also can be cycled for 1000 h continuously without short‐circuit. Such results indicate the good feasibility of as‐proposed sintering strategy to prepare uniformly dense garnet type solid‐state electrolytes for solid‐state lithium batteries. [ABSTRACT FROM AUTHOR]

Ether electrolytes exhibit better rate kinetics than carbonate ester electrolytes when used in several kinds of anode materials, especially in hard carbon (HC) for sodium‐ion batteries (SIBs). However, the mechanism causing the remarkable kinetics difference is still unclear. Here, a three‐electrode system is used first to eliminate the influence of polarization from the Na counter electrode. Then, there is systematic exploration from three steps of the electrode reaction process (Na+ storage in HC; de‐solvation; Na+ migration through solid electrolyte interphase (SE), and the underlying mysteries are uncovered. For Na+ storage in the bulk of the HC, it is found that two systems show the same storage mechanism and Na metallic nanoparticles will appear when discharged to 0.1 V. In addition, faster de‐solvation of the ether electrolyte is uncovered by three‐electrode temperature‐dependent EIS and solvation free energies calculation. Moreover, the difference of the SEI layers is unraveled by X‐ray photoelectron spectroscopy etching, scanning electron microscopy, and differential electrochemical mass spectrometry. Most importantly, by discriminating the impacts of the SEI layers and de‐solvation behavior, it can be concluded that the de‐solvation process is the rate‐controlling step of the electrode reaction process and is the main factor causing the kinetics differences between the two electrolytes. The research provides a clear mechanism to illuminate fast kinetics for ether electrolytes, which will promote its application in SIBs. [ABSTRACT FROM AUTHOR]

Single‐crystal nickel‐rich cathode materials (SC‐NRCMs) are the most promising candidates for next‐generation power batteries which enable longer driving range and reliable safety. In this review, the outstanding advantages of SC‐NRCMs are discussed systematically in aspects of structural and thermal stabilities. Particularly, the intergranular‐crack‐free morphology exhibits superior cycling performance and negligible parasitic reactions even under severe conditions. Besides, various synthetic methods are summarized and the relation between precursor, sintering process, and final single‐crystal products are revealed, providing a full view of synthetic methods. Then, challenges of SC‐NRCMs in fields of kinetics of lithium diffusion and the one particularly occurred at high voltage (intragranular cracks and aggravated parasitic reactions) are discussed. The corresponding mechanism and modifications are also referred. Through this review, it is aimed to highlight the magical morphology of SC‐NRCMs for application perspective and provide a reference for following researchers. [ABSTRACT FROM AUTHOR]

Cu and Fe are the main impurity elements in the hydrometallurgical regeneration of spent lithium‐ion batteries. Hence, it is important to study the effect of Cu and Fe doping on the structures and electrochemical properties of cathode materials. In this study, a series of Cu‐ and/or Fe‐doped LiNi0.8Co0.15Al0.05O2 cathode materials are synthesized by spray pyrolysis and high‐temperature solid‐state method. The inductively coupled plasma (ICP), X‐ray diffraction (XRD), and Rietveld refinement results reveal that Cu and Fe can incorporate into the crystal lattice and cation mixing is suppressed. The X‐ray photoelectron spectroscope (XPS) results show that the relative ratio of Ni2+/Ni3+ on the surface is effectively decreased. Electrochemical results display that the electrochemical performances of Cu‐ and/or Fe‐doped samples are improved when the atomic ratio of Ni to Cu and Ni to Fe is greater than 79.0 and 399.0, respectively. The dQ/dV, GITT, EIS, XRD, and XPS studies indicate that the structure stability, Li+ diffusion coefficient, and charge transfer can be increased by appropriate Cu and/or Fe substitution. The results suggest that appropriate Cu and Fe can be doped into LiNi0.8Co0.15Al0.05O2 as beneficial elements rather than removed as impurities. [ABSTRACT FROM AUTHOR]

The mono‐active bimetallic oxide Co2AlO4 with microsphere morphology and yolk‐shell structure are synthesized and first evaluated as anode materials for lithium ion batteries. The electrochemically inactive Al element disperse well in the material at an atomic‐scale level, which can effectively alleviate volume expansion during the cycling and heighten the electrochemical reaction kinetics. Moreover, the yolk‐shell structure provides adequate buffer space for volume expansion. Benefited from the synergy effect of the yolk‐shell structure and uniformly element Al distribution, the yolk‐shell Co2AlO4 delivers a discharge capacity of 661 mAh g−1 at 1000 mA g−1 after 500 cycles with a capacity retention ratio of 86.4 %, and maintains a high discharge capacity of 548 mAh g−1 at 3200 mA g−1, showing excellent long‐term cycle performance and rate capability. [ABSTRACT FROM AUTHOR]

Endowed with high theoretical energy density, low cost, and environmental friendliness, lithium‐sulfur batteries have a promising future in energy storage. The volume expansion of the sulfur cathode, shuttle effects, and the insulating nature of polysulfide result in poor cycling stability and limit practical applications of lithium‐sulfur batteries. In this work, these matters are relieved by physically and chemically restricting sulfur species in highly fluorinated sulfur‐rich multiple covalent triazine frameworks synthesized through nucleophilic aromatic substitution reaction chemistry. It exhibits a specific capacity of 681 mAh g−1 and capacity retention of 62.6 % after 400 cycles, indicating a 0.09 % degradation per cycle. The superiority in cycle performance is attributed to the homogeneous distribution of sulfur, covalent bonding of sulfur, and affinity for polysulfide of triazine rings. [ABSTRACT FROM AUTHOR]

The rapid rise of electrode impedance and capacity decay of Ni‐rich layered cathode materials during high‐voltage cycling are rooted in their severe structural degradation. Here we present a feasible strategy, anchoring ∼1 % K+ into the Li+ sites of LiNi0.8Co0.15Al0.05O2 as an excellent structural stabilizer, to overcome aforementioned issues, and the similarities and differences in terms of modification mechanism is compared with Na+. Showing difference with Na+ that tends to migrate into electrolyte during high‐voltage cycling, K+ occupies in Li+ site firmly because of its larger ionic radius and lower migrating ability, which sustainably prevent the irreversible phase transition between two hexagonal phases (H2 and H3) and impede the cation migration in highly delithiated state, thus suppressing the structural degradation. Benefiting from these merits, Li0.99K0.01Ni0.8Co0.15Al0.05O2 delivers a large initial discharge capacity of 217 mAh g−1 at 0.1 C and maintains stable cycling at 1 C in a high voltage of 4.6 V (remaining 87.4 % of its initial capacity after 150 cycles). The mechanism proposed in this work, accounting for enhanced structural stability under high‐voltage cycling by K+ anchoring in Ni‐rich cathode materials, provides a vital hint for rational designing advanced cathode materials to pursue high energy density Li‐ion batteries. K+ anchoring in Li+ sites of LiNi0.8Co0.15Al0.05O2 prevent the collapse of host structure and inhibit cation migration in highly delithiated state. Benefit from these, Li0.99K0.01Ni0.8Co0.15Al0.05O2 exhibits superior high‐voltage electrochemical performances. [ABSTRACT FROM AUTHOR]

This study focuses on suppressing the voltage decay and improving the electrochemical performance of Li‐rich and manganese‐based (LRM) material by Nb2O5 coating, which is realized by an effective soft‐chemical route using a mixture of ethanol and water as co‐solvent. After Nb2O5 coating, the resulted material demonstrates superior electrochemical performance as cathode material for LIBs. Particularly, it shows an excellent capacity retention of 98 % after 200 cycles at 1 C (1 C=250 mA g−1). Voltage decay within cycling is also obviously suppressed by Nb2O5 coating. Moreover, it exhibits superior rate capacities, delivering 189 and 152 mAh g−1 at high current densities of 2 and 5 C, respectively. The improved electrochemical performance of Nb2O5 coated sample can be attributed to that Nb2O5 can suppress the phase transformation and voltage decay by acting as not only a fast ion conductor to accelerate the lithium ion diffusion at the cathode/electrolyte interface, but also an inert protective layer to reduce the direct contact between the cathode and electrolyte. A study on the suppressing the voltage decay and improving the electrochemical performance of Li‐rich and manganese‐based (LRM) material by Nb2O5 coating, the protective effects of Nb2O5 have been investigated systematically. [ABSTRACT FROM AUTHOR]

An issue associated with lithium−sulfur (Li−S) batteries is polysulfide dissolution, leading to the serious crossover of polysulfide to the Li anode. To address this issue, we report on a multifunctional separator prepared by introducing a porous carbon/multi-walled carbon nanotube (PC/MWCNT) composite into a commercial separator. It shows that the PC/MWCNT composite is able to enhance the interfacial interaction between the coating and the polysulfide and provides a large surface area for absorbing the polysulfide, thus improving the electrical conductivity. It has been demonstrated that the Li−S cell constructed with the PC/MWCNT composite separator results in a reversible capacity as high as 659 mAh g−1 after 200 cycles at 0.5 C, and the average capacity fading rate of the cell is about 0.138 % per cycle. The performance improvement is attributed to a reduction in the crossover rate of polysulfide through the composite separator as a result of the polysulfide absorption by PC/MWCNT layer. [ABSTRACT FROM AUTHOR]

Dimethyl sulfoxide ( DMSO) is widely used in biological studies as a cryoprotective agent for cells and tissues, and also for cryopreserved platelets ( PLTs). However, few data on the toxic effects of DMSO following intravenous infusion of cryopreserved PLTs are available. The aim of this study was to explore dose-related effects of DMSO on red blood cells ( RBCs), PLTs and vascular endothelial cells in vitro. The results showed that DMSO treatments had significant effects on RBCs, affecting osmotic fragility and increasing hemolysis. Free hemoglobin ( FHb) level of RBCs was 0.64 ± 0.19 g L−1 after incubation for 6 h with 0.6% DMSO, and these levels were elevated compared with controls (0.09 ± 0.05 g L−1). Aggregation of PLTs induced by adenosine diphosphate, thrombin ( THR), and thrombin receptor activator peptide ( TRAP) were inhibited by DMSO treatment because the THR generation capacity was reduced. The intensity of the cytosolic esterase-induced fluorescence response from carboxy dimethyl fluorescein diacetate ( CMFDA) in PLTs was decreased about 29% ± 0.04% after treatment with DMSO. DMSO also inhibited the proliferation of the vascular endothelial cell line EAhy926 cells by blocking the G1 phase. Apoptosis of EAhy926 cells with 0.6% DMSO stimulation was increased threefold compared to controls. On the basis of these findings, it was concluded that DMSO was toxic to the hematologic system. This should be taken into account when assessing the infusion effects of cryopreserved PLTs or other blood products requiring DMSO as a vehicle, such as cryopreserved stem cells, in order to avoid adverse therapeutic effects. [ABSTRACT FROM AUTHOR]

To develop a new anode material to meet the increasing demands of lithium-ion battery, MoS2 is used for the first time to modify the C/LiVPO4F anode to improve its lithium-storage performance between 3 and 0.01 V. Morphological observations reveal that the MoS2-modified C/LiVPO4F particles (M-LVPF) are wrapped by an amorphous carbon as interlayer and layered MoS2 as external surface. Charge-discharge tests show that M-LVPF delivers a high reversible capacity of 308 mAh g−1 at 50 mA g−1. After 300 cycles at 1.0 A g−1, a capacity retention of 98.7 % is observed. Moreover, it exhibits high rate capability with a specific capacity of 199 mAh g−1 at 1.6 A g−1. Electrochemical impedance spectroscopy tests indicate that the lithium-ion diffusion and charge-exchange reaction at the surface of M-LVPF are greatly enhanced. First-principles calculations for the MoS2 (001)/C/LiVPO4F (010) system demonstrate that the absorption of MoS2 on C/LiVPO4F is exothermic and spontaneous and that the electron transfer at the MoS2-absorbed C/LiVPO4F surface is enhanced. [ABSTRACT FROM AUTHOR]

We demonstrate the facile and well-controlled design and fabrication of heterostructured and hierarchical 3D mesoporous NiSi x/NiCo2O4 core/shell nanowire arrays on nickel foam through a facile chemical vapor deposition (CVD) technique combined with a simple but powerful chemical bath deposition (CBD) technique. The smart hybridization of NiCo2O4 and NiSi x nanostructures results in an intriguing mesoporous hierarchical core/shell nanowire-array architecture. The nanowire arrays demonstrate enhanced electrochemical performance as binder- and conductive-agent-free electrodes for lithium ion batteries (LIBs) with excellent capacity retention and high rate capability on cycling. The electrodes can maintain a high reversible capacity of 1693 mA h g−1 after 50 cycles at 200 mA g−1. Given the outstanding performance and simple, efficient, cost-effective fabrication, we believe that these 3D NiSi x/NiCo2O4 core/shell heterostructured arrays have great potential application in high-performance LIBs. [ABSTRACT FROM AUTHOR]

Human mesenchymal stem cells (hMSCs) hold great promise in cell therapy and regenerative medicine. Various preclinical and clinical trials have been carried out to illustrate the therapeutic potential of these cells. However, one major challenge for manufacturing clinical grade hMSCs is the requisition of current good manufacturing practice (cGMP) grade practices in cell isolation, processing, storage, and distribution. Development of non-toxic and animal serum-free preservation medium is critical for storage and distribution of mesenchymal stem cells (MSCs). In this study, we developed a solution formula that could preserve MSCs at 4°C for up to 3 weeks. In the solution, trehalose is a key ingredient for maintaining survival of MSCs. Among the concentrations investigated, 40 mM trehalose showed the best outcome with the viability maintained more than 92.7 ± 1.5% for 7 days. Cells preserved in the solution formula for 3 weeks still remained about 70% viability, and produced results similar to those of freshly harvested hMSCs in terms of growth kinetics, expression profile of cell surface antigens, and differentiation potential. In summary, storage of MSCs in the medium makes it far easier for transporting the cells from processing units to clinical sites. J. Cell. Physiol. 227: 879-884, 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective Previous reports of cells from patients with systemic lupus erythematosus (SLE) note that repair of single-strand breaks is delayed, and these lesions may be converted to double-strand breaks (DSBs) at DNA replication forks. We undertook this study to assess the integrity of DSB recognition, signaling, and repair mechanisms in B lymphoblastoid cell lines derived from patients with pediatric SLE. Methods Nine assays were used to interrogate DSB repair and recognition in lymphoblastoid cell lines from patients with pediatric SLE, including the neutral comet assay (NCA), colony survival assay (CSA), irradiation-induced foci formation for γ-H2AX and 53BP1 proteins, kinetics of phosphorylation of structural maintenance of chromosomes protein 1 (SMC1), postirradiation bromodeoxyuridine incorporation to evaluate S phase checkpoint integrity, monoubiquitination of Fanconi protein D2 , ATM protein expression, and non-homologous DNA end joining protein expression and function. Results Three of the 9 assays revealed abnormal patterns of response to irradiation-induced DNA damage. The NCA and CSA yielded aberrant results in the majority of SLE lymphoblastoid cell lines. Abnormal prolongation of SMC1 phosphorylation was also noted in 2 of 16 SLE lymphoblastoid cell lines. Conclusion Our data suggest that DSB repair is defective in some lymphoblastoid cell lines from pediatric patients with SLE, especially when assessed by both NCA and CSA. Since these studies are nonspecific, further studies of DNA repair and kinetics are indicated to further delineate the underlying pathogenesis of SLE and possibly identify therapeutic targets. [ABSTRACT FROM AUTHOR]

Background: Membrane grafting of methoxypolyethylene glycol (mPEG) provides a unique strategy in preventing the immunologic recognition in blood transfusion. mPEG-modified red blood cells (mPEG-RBCs) have acceptable in vitro properties and provide a useful solution to problems with clinical blood matching. The aim of this study was to demonstrate the physiologic normality of mPEG-RBCs in mice. Study Design and Methods: Mouse RBCs were withdrawn via cardiac bleed and modified with 1.0 mmol per L mPEG with succinimidyl propionate linker. The fluorescein-labeled mPEG-RBCs were then transfused into recipient mice for in vivo survival analysis. At the same time, the exsanguine mouse model was produced, and mice were transfused with mPEG-RBCs. The effects of mPEG-RBC transfusion on the hemoglobin (Hb) level, swimming endurance capacity, and hypoxic-ischemic injury in hippocampal pyramidal cells of exsanguine mice were investigated. Results: mPEG-RBCs showed the same in vivo survival curve and t((1/2)) as those of untreated RBCs. Transfusion of mPEG-RBCs could elevate Hb level of exsanguine mice and improve their swimming endurance capacity, and histologic studies showed that mPEG-RBCs could also restore the hypoxic-ischemic injury of hippocampal pyramidal cells in exsanguine mice, which were similar with control RBCs. That is, mPEG-RBCs functioned in a similar fashion to untreated RBCs in exsanguine mice. Therefore, these results revealed that mPEG-RBCs had normal oxygen-carrying capacity. Conclusion: In conclusion, the results confirmed that mPEG-RBCs could perform their in vivo function of carrying O(2) and improve some physiologic indexes of exsanguine mice, and the physiologic normality of mPEG-RBCs provides new findings for clinical use. [ABSTRACT FROM AUTHOR]

The solid electrolyte interphase (SEI) plays an important role in the comprehensive electrochemical performance of lithium‐ion batteries. However, graphite generates a 10% volume expansion during cycles, resulting in structural cracking of the SEI and further electrolyte decomposition. Herein, by adjusting the formation current density, the composition and structure of the SEI are regulated to optimize the electrochemical performance of graphite electrodes. The results manifest that the SEI is mainly formed between 1.1 and 1.4 V, and a lower formation current density is favorable for forming an excellent SEI at the graphite electrode surface. The SEI formed under such condition possesses more organic lithium salts and less inorganic lithium salts, and it is enwrapped onto the surface of the graphite anode more uniformly as compared with higher formation current density. Meanwhile, the derived SEI is more stable and thicker, which can effectively stabilize the interface of the electrode/electrolyte to enhance the cyclic stability of graphite anode materials after the formation step, so as to buffer its volume change during the cycles. [ABSTRACT FROM AUTHOR]

Lithium‐ion hybrid supercapacitors (LICs) are considered as a promising candidate in energy storage systems. Taking the factor of sluggish kinetics behavior, battery‐type anode plays a significant role in improving the performance of LICs. Here, onion‐shaped graphene‐like derivatives are synthesized via carbonization of metalorganic quantum dots (MQDs) accompanied with in situ catalytic graphitization by reduced metal. Notably MQDs, exhibiting water‐soluble character and ultrafine particles (2.5–5.5 nm) morphology, are prepared by the amidation reaction. The carbonized sample exhibits highly graphitic tendency with graphitization degree up to 95.6%, and shows graphene‐like porous structure, appropriate amorphous carbon decoration characteristic, as well as N‐doping and defective nature. When employed as anode material in LICs, it shows high energy density of 83.7 Wh kg–1 and high power density of 6527 W kg–1 when the mass ratio of cathode to anode is 1:1 and the operating voltage ranges from 2.0 to 4.0 V. It also possesses the long cyclic stability with the energy density retention maintains at 97.3% after 10 000 cycles at 5.0 A g–1. In addition, the energy density is further increased by altering cathode/anode mass ratio and extending working voltage. This work provides a novel strategy to develop unique carbon materials for energy storage. Water‐soluble metalorganic quantum dots are synthesized and their derivative porous graphitic carbons (PGCs) are achieved accompanied with in situ catalytic graphitization process. The obtained PGCs exhibit high plateau capacity and superior rate capability, making them very promising anode materials for lithium‐ion capacitors, benefiting from the high graphitization degree, graphene‐like porous shape, appropriate amorphous carbon decoration, and N‐doping and defect‐rich natures. [ABSTRACT FROM AUTHOR]