Advanced parametrization for the production of high-energy solid-state lithium pouch cells containing polymer electrolytes.

Lithium batteries with solid-state electrolytes are an appealing alternative to state-of-the-art non-aqueous lithium-ion batteries with liquid electrolytes because of safety and energy aspects. However, engineering development at the cell level for lithium batteries with solid-state electrolytes is limited. Here, to advance this aspect and produce high-energy lithium cells, we introduce a cell design based on advanced parametrization of microstructural and architectural parameters of electrode and electrolyte components. To validate the cell design proposed, we assemble and test (applying a stack pressure of 3.74 MPa at 45 °C) 10-layer and 4-layer solid-state lithium pouch cells with a solid polymer electrolyte, resulting in an initial specific energy of 280 Wh kg-1 (corresponding to an energy density of 600 Wh L-1) and 310 Wh kg-1 (corresponding to an energy density of 650 Wh L-1) respectively.

Carrageenan as a Sacrificial Binder for 5 V LiNi0.5 Mn1.5 O4 Cathodes in Lithium-Ion Batteries.

5 V-class LiNi0.5 Mn1.5 O4 (LNMO) with its spinel symmetry is a promising cathode material for lithium-ion batteries. However, the high-voltage operation of LNMO renders it vulnerable to interfacial degradation involving electrolyte decomposition, which hinders long-term and high-rate cycling. Herein, this longstanding challenge presented by LNMO is overcome by incorporating a sacrificial binder, namely, λ-carrageenan (CRN), a sulfated polysaccharide. This binder not only uniformly covers the LNMO surface via hydrogen bonding and ion-dipole interaction but also offers an ionically conductive cathode-electrolyte interphase layer containing LiSOx F, a product of the electrochemical decomposition of the sulfate group. Taking advantage of these two auspicious properties, the CRN-based electrode exhibits cycling and rate performance far superior to that of its counterparts based on the conventional poly(vinylidene difluoride) and sodium alginate binders. This study introduces a new concept, namely "sacrificial" binder, for battery electrodes known to deliver superior electrochemical performance but be adversely affected by interfacial instability.

NAB2-STAT6 fusion protein mediates cell proliferation and oncogenic progression via EGR-1 regulation.

Solitary fibrous tumors are rare mesenchymal tumors derived from soft tissues and vascular walls. NAB2-STAT6 fusion gene serves as a marker gene for this disease and consists of the truncated repressor domain of NGFI-A-Binding protein 2 (NAB2) and the intact activation domain of STAT6. In this study, we found that EGR-1 and the proliferation-related EGR-1 target gene IGF2 were upregulated in NIH-3T3 cells transfected with NAB2-STAT6. Additionally, p-Rb (Ser795) and cyclin D1 levels were upregulated, and cell proliferation was also enhanced. We identified that treatment with the IGF2 inhibitor reduced cell proliferation in NIH-3T3 cells transfected with NAB2-STAT6. The oncogenic progression was enhanced in NIH-3T3 cells transfected with NAB2-STAT6 compared with those transfected with the empty vector. Taken together, our study suggests that the NAB2-STAT6 fusion gene is associated with cell proliferation through EGR-1 transcriptional expression and IGF2 can be a drug target for the treatment of solitary fibrous tumors.

A Pyrene-Poly(acrylic acid)-Polyrotaxane Supramolecular Binder Network for High-Performance Silicon Negative Electrodes.

Although being incorporated in commercial lithium-ion batteries for a while, the weight portion of silicon monoxide (SiOx , x ≈ 1) is only less than 10 wt% due to the insufficient cycle life. Along this line, polymeric binders that can assist in maintaining the mechanical integrity and interfacial stability of SiOx electrodes are desired to realize higher contents of SiOx . Herein, a pyrene-poly(acrylic acid) (PAA)-polyrotaxane (PR) supramolecular network is reported as a polymeric binder for SiOx with 100 wt%. The noncovalent functionalization of a carbon coating layer on the SiOx is achieved by using a hydroxylated pyrene derivative via the π-π stacking interaction, which simultaneously enables hydrogen bonding interactions with the PR-PAA network through its hydroxyl moiety. Moreover, the PR's ring sliding while being crosslinked to PAA endows a high elasticity to the entire polymer network, effectively buffering the volume expansion of SiOx and largely mitigating the electrode swelling. Based on these extraordinary physicochemical properties of the pyrene-PAA-PR supramolecular binder, the robust cycling of SiOx electrodes is demonstrated at commercial levels of areal loading in both half-cell and full-cell configurations.

Highly Elastic Polyrotaxane Binders for Mechanically Stable Lithium Hosts in Lithium-Metal Batteries.

Despite their unparalleled theoretical capacity, lithium-metal anodes suffer from well-known indiscriminate dendrite growth and parasitic surface reactions. Conductive scaffolds with lithium uptake capacity are recently highlighted as promising lithium hosts, and carbon nanotubes (CNTs) are an ideal candidate for this purpose because of their capability of percolating a conductive network. However, CNT networks are prone to rupture easily due to a large tensile stress generated during lithium uptake-release cycles. Herein, CNT networks integrated with a polyrotaxane-incorporated poly(acrylic acid) (PRPAA) binder via supramolecular interactions are reported, in which the ring-sliding motion of the polyrotaxanes endows extraordinary stretchability and elasticity to the entire binder network. In comparison to a control sample with inelastic binder (i.e., poly(vinyl alcohol)), the CNT network with PRPAA binder can endure a large stress during repeated lithium uptake-release cycles, thereby enhancing the mechanical integrity of the corresponding electrode over battery cycling. As a result, the PRPAA-incorporated CNT network exhibits substantially improved cyclability in lithium-copper asymmetric cells and full cells paired with olivine-LiFePO4 , indicating that high elasticity enabled by mechanically interlocked molecules such as polyrotaxanes can be a useful concept in advancing lithium-metal batteries.

Highly elastic binders integrating polyrotaxanes for silicon microparticle anodes in lithium ion batteries.

Lithium-ion batteries with ever-increasing energy densities are needed for batteries for advanced devices and all-electric vehicles. Silicon has been highlighted as a promising anode material because of its superior specific capacity. During repeated charge-discharge cycles, silicon undergoes huge volume changes. This limits cycle life via particle pulverization and an unstable electrode-electrolyte interface, especially when the particle sizes are in the micrometer range. We show that the incorporation of 5 weight % polyrotaxane to conventional polyacrylic acid binder imparts extraordinary elasticity to the polymer network originating from the ring sliding motion of polyrotaxane. This binder combination keeps even pulverized silicon particles coalesced without disintegration, enabling stable cycle life for silicon microparticle anodes at commercial-level areal capacities.

Delicate Structural Control of Si-SiOx-C Composite via High-Speed Spray Pyrolysis for Li-Ion Battery Anodes.

Despite the high theoretical capacity, silicon (Si) anodes in lithium-ion batteries have difficulty in meeting the commercial standards in various aspects. In particular, the huge volume change of Si makes it very challenging to simultaneously achieve high initial Coulombic efficiency (ICE) and long-term cycle life. Herein, we report spray pyrolysis to prepare Si-SiOx composite using an aqueous precursor solution containing Si nanoparticles, citric acid, and sodium hydroxide (NaOH). In the precursor solution, Si nanoparticles are etched by NaOH with the production of [SiO4]4-. During the dynamic course of spray pyrolysis, [SiO4]4- transforms to SiOx matrix and citric acid decomposes to carbon surface layer with the assistance of NaOH that serves as a decomposition catalyst. As a result, a Si-SiOx composite, in which Si nanodomains are homogeneously embedded in the SiOx matrix with carbon surface layer, is generated by a one-pot process with a residence time of only 3.5 s in a flow reactor. The optimal composite structure in terms of Si domain size and Si-to-O ratio exhibited excellent electrochemical performance, such as reversible capacity of 1561.9 mAh g-1 at 0.06C rate and ICE of 80.2% and 87.9% capacity retention after 100 cycles at 1C rate.

Controlled Prelithiation of Silicon Monoxide for High Performance Lithium-Ion Rechargeable Full Cells.

Despite the recent considerable progress, the reversibility and cycle life of silicon anodes in lithium-ion batteries are yet to be improved further to meet the commercial standards. The current major industry, instead, adopts silicon monoxide (SiOx, x ≈ 1), as this phase can accommodate the volume change of embedded Si nanodomains via the silicon oxide matrix. However, the poor Coulombic efficiencies (CEs) in the early period of cycling limit the content of SiOx, usually below 10 wt % in a composite electrode with graphite. Here, we introduce a scalable but delicate prelithiation scheme based on electrical shorting with lithium metal foil. The accurate shorting time and voltage monitoring allow a fine-tuning on the degree of prelithiation without lithium plating, to a level that the CEs in the first three cycles reach 94.9%, 95.7%, and 97.2%. The excellent reversibility enables robust full-cell operations in pairing with an emerging nickel-rich layered cathode, Li[Ni0.8Co0.15Al0.05]O2, even at a commercial level of initial areal capacity of 2.4 mAh cm(-2), leading to a full cell energy density 1.5-times as high as that of graphite-LiCoO2 counterpart in terms of the active material weight.

Double tension band wiring for treatment of olecranon fractures.

PURPOSE: Although tension band wiring (TBW) is generally accepted as standard treatment for olecranon fractures, it has several shortcomings such as loss of reduction, skin irritation, and migration of the K-wires. To overcome these problems and increase fixation stability, we used a rigid fixation technique with double tension band wiring (DTBW). Here, we describe the technique and outcomes of the treatment. METHODS: We retrospectively reviewed 21patients with olecranon fractures who were treated by DTBW. We evaluated clinical and radiological outcomes by checking the range of motion, loss of reduction, functional scoring, skin complications, and pin migration. There were 15 cases of Mayo type IIA fractures (71%) and 6 of type IIB fractures (29%). The mean follow-up period was 37 months (range, 12-58 mo). We also compared the mechanical stability of DTBW and TBW in a sawbone model using a single cycle load to failure protocol. RESULTS: All fractures united without displacement, and no migration of the K-wires was observed during the period of follow-up. Mean loss of elbow extension was 2° (range, 0°-15°) and mean elbow flexion was 134° (range, 125°-140°). The mean Mayo Elbow Performance Score was 94 (range, 70-100). Biomechanical testing revealed greater mechanical strength in the DTBW technique than in the TBW when measured by mean maximum failure load and mean bending moment at failure. CONCLUSIONS: DTBW produced good clinical and radiological outcomes and could be an effective option for the treatment of olecranon fractures by providing additional stability through a second TBW. Biomechanical comparison with a control group (TBW) supported the mechanical benefits of DTBW. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Scalable fracture-free SiOC glass coating for robust silicon nanoparticle anodes in lithium secondary batteries.

A variety of silicon (Si) nanostructures and their complex composites have been lately introduced in the lithium ion battery community to address the large volume changes of Si anodes during their repeated charge-discharge cycles. Nevertheless, for large-scale manufacturing it is more desirable to use commercial Si nanoparticles with simple surface coating. Most conductive coating materials, however, do not accommodate the volume expansion of the inner Si active phases and resultantly fracture during cycling. To overcome this chronic limitation, herein, we report silicon oxycarbide (SiOC) glass as a new coating material for Si nanoparticle anodes. The SiOC glass phase can expand to some extent due to its active nature in reacting with Li ions and can therefore accommodate the volume changes of the inner Si nanoparticles without disintegration or fracture. The SiOC glass also grows in the form of nanocluster to bridge Si nanoparticles, thereby contributing to the structural integrity of secondary particles during cycling. On the basis of these combined effects, the SiOC-coated Si nanoparticles reach a high reversible capacity of 2093 mAh g(-1) with 92% capacity retention after 200 cycles. Furthermore, the coating and subsequent secondary particle formation were produced by high-speed spray pyrolysis based on a single precursor solution.

Wearable textile battery rechargeable by solar energy.

Wearable electronics represent a significant paradigm shift in consumer electronics since they eliminate the necessity for separate carriage of devices. In particular, integration of flexible electronic devices with clothes, glasses, watches, and skin will bring new opportunities beyond what can be imagined by current inflexible counterparts. Although considerable progresses have been seen for wearable electronics, lithium rechargeable batteries, the power sources of the devices, do not keep pace with such progresses due to tenuous mechanical stabilities, causing them to remain as the limiting elements in the entire technology. Herein, we revisit the key components of the battery (current collector, binder, and separator) and replace them with the materials that support robust mechanical endurance of the battery. The final full-cells in the forms of clothes and watchstraps exhibited comparable electrochemical performance to those of conventional metal foil-based cells even under severe folding-unfolding motions simulating actual wearing conditions. Furthermore, the wearable textile battery was integrated with flexible and lightweight solar cells on the battery pouch to enable convenient solar-charging capabilities.

Enhanced delivery of siRNA complexes by sonoporation in transgenic rice cell suspension cultures.

Small interfering synthetic double-stranded RNA (siRNA) was applied to suppress the expression of the human cytotoxic- T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) gene transformed in transgenic rice cell cultures. The sequence of the 21-nucleotide siRNA was deliberately designed and synthesized with overhangs to inactivate the expression of hCTLA4Ig. The chemically synthesized siRNA duplex was combined with polyethyleneimine (PEI) at a mass ratio of 1:10 (0.33 microg siRNA:3.3 microg PEI) to produce complexes. The siRNA complexes (siRNA+PEI) were labeled with Cy3 in order to subsequently confirm the delivery by fluorescent microscopy. In addition, the cells were treated with sonoporation at 40 kHz and 419 W for 90 s to improve the delivery. The siRNA complexes alone inhibited the expression of hCTLA4Ig to 45% compared with control. The siRNA complexes delivered with sonoporation downregulated the production of hCTLA4Ig to 73%. Therefore, we concluded that the delivery of siRNA complexes into plant cells could be enhanced successfully by sonoporation.