The status and problems of upscaling research on perovskite solar cells, which must be addressed for commercialization efforts to be successful, are investigated. An 804 cm2 perovskite solar module ...has been reported with 17.9% efficiency, which is significantly lower than the champion perovskite solar cell efficiency of 25.2% reported for a 0.09 cm2 aperture area. For the realization of upscaling high‐quality perovskite solar cells, the upscaling and development history of conventional silicon, copper indium gallium sulfur/selenide and CdTe solar cells, which are already commercialized with modules of sizes up to ≈25 000 cm2, are reviewed. GaAs, organic, dye‐sensitized solar cells and perovskite/silicon tandem solar cells are also reviewed. The similarities of the operating mechanisms between the various solar cells and the origin of different development pathway are investigated, and the ideal upscaling direction of perovskite solar cells is subsequently proposed. It is believed that lessons learned from the historical analysis of various solar cells provide a fundamental diagnosis of relative and absolute development status of perovskite solar cells. The unique perspective proposed here can pave the way toward the upscaling of perovskite solar cells.
Lessons learned from the historical analysis of diverse solar cells provide a fundamental diagnosis of the relative and absolute development status of perovskite solar cells. The upscaling of perovskite solar cells and commercialization of various solar cells are comparatively analyzed and feasible technologies that can be applied to the perovskite upscaling process, both now and in the future, are suggested.
A circuit for balancing Li-ion battery cells is proposed. This circuit requires one small transformer and N + 3 bilateral switches to equalize the charging states of N serially connected battery ...cells. The transformer works as an energy carrier, and the switches select two unbalanced cells that require an energy transfer from one to the other cell. The circuit was tested for a 12-cell Li-ion battery under static, cyclic, and dynamic charging/discharging conditions. Under static condition, the power-transfer efficiency was measured as 80.4% at a balancing power of 0.78 W; two 4400-mA·h battery cells at a state of charge (SOC) = 70 and 80% were equalized after 78 min. The results of cyclic and dynamic charging/discharging conditions show that the circuit is appropriate for balancing the Li-ion battery cells for vehicles and energy storage systems.
A modularized design of an active charge equalizer and a charge equalization algorithm for a Li-ion battery pack are proposed in this paper. The equalizer consists of one module-balancing circuit and ...M cell-balancing circuits, where M is the number of modules in the battery pack. Each balancing circuit uses an inductor that is placed in a bridge of four bidirectional switches and works as an energy carrier, and uses a cell/module access network that enables energy transfer from one cell/module to another cell or module. The charge equalization between modules can be performed simultaneously with that between cells, so the proposed circuit can significantly reduce the time required to equalize the charges of all cells in the battery pack. The proposed circuit was tested under various charging/discharging conditions for a battery pack composed of four serially connected modules, with four serially connected cells per module. Experimental results show that the proposed circuit and algorithm comprise a good solution to balance a Li-ion battery pack.
Abstract
Organic-inorganic hybrid perovskite solar cells (PSCs) have been extensively studied because of their outstanding performance: a power conversion efficiency exceeding 22% has been achieved. ...The most commonly used PSCs consist of CH
3
NH
3
PbI
3
(MAPbI
3
) with a hole-selective contact, such as 2,2′,7,7′-tetrakis(
N
,
N
-di-
p
-methoxyphenylamine)-9,9-spiro-bifluorene (spiro-OMeTAD), for collecting holes. From the perspective of long-term operation of solar cells, the cell performance and constituent layers (MAPbI
3
, spiro-OMeTAD, etc.) may be influenced by external conditions like temperature, light, etc. Herein, we report the effects of temperature on spiro-OMeTAD and the interface between MAPbI
3
and spiro-OMeTAD in a solar cell. It was confirmed that, at high temperatures (85 °C), I
−
and CH
3
NH
3
+
(MA
+
) diffused into the spiro-OMeTAD layer in the form of CH
3
NH
3
I (MAI). The diffused I
−
ions prevented oxidation of spiro-OMeTAD, thereby degrading the electrical properties of spiro-OMeTAD. Since ion diffusion can occur during outdoor operation, the structural design of PSCs must be considered to achieve long-term stability.
The transferred microbiota from mother to baby constitutes the initial infant gastrointestinal microbiota and has an important influence on the development and health of infants in human. However, ...the reproductive tract microbiota of avian species and its inheritance have rarely been studied. We aimed to characterize the microbial community in the chicken reproductive tract and determine the origin of the chicken embryo gut microbiota. Microbiota in four different portions of chicken oviduct were determined using 16S rRNA metagenomic approach with the IonTorrent platform. Additionally, we analyzed the mother hen's magnum and cloaca, descendent egg, and embryo gut microbiota. The microbial composition and relative abundance of bacterial genera were stable throughout the entire chicken reproductive tract, without significant differences between the different parts of the oviduct. The chicken reproductive tract showed a relatively high abundance of Lactobacillus species. The number of bacterial species in the chicken reproductive tract significantly increased following sexual maturation. Core genera analysis detected 21 of common genera in the maternal magnum and cloaca, descendent egg shell, egg white, and embryo gut. Some elements of the maternal oviduct microbiota appear to be transferred to the embryo through the egg white and constitute most of the embryo gut bacterial population.
Most memory-chip manufacturers keep trying to supply cost-effective storage devices with high-performance characteristics such as shorter tPROG, lower power consumption and higher endurance. For many ...years, every effort has been made to shrink die size to lower cost and to improve performance. However, the previously used node-shrinking methodology is facing challenges due to increased cell-to-cell interference and patterning difficulties caused by decreasing dimension. To overcome these limitations, 3D-stacking technology has been developed. As a result of long and focused research in 3D stacking technology, we succeed in developing 128 Gb 3b/cell Vertical NAND with 32 stack WL layers for the first time, which is the smallest 128 Gb NAND Flash. The die size is 68.9 mm 2 , program time is 700 us and I/O rate is 1 Gb/s.
We report proteogenomic analysis of diffuse gastric cancers (GCs) in young populations. Phosphoproteome data elucidated signaling pathways associated with somatic mutations based on ...mutation-phosphorylation correlations. Moreover, correlations between mRNA and protein abundances provided potential oncogenes and tumor suppressors associated with patient survival. Furthermore, integrated clustering of mRNA, protein, phosphorylation, and N-glycosylation data identified four subtypes of diffuse GCs. Distinguishing these subtypes was possible by proteomic data. Four subtypes were associated with proliferation, immune response, metabolism, and invasion, respectively; and associations of the subtypes with immune- and invasion-related pathways were identified mainly by phosphorylation and N-glycosylation data. Therefore, our proteogenomic analysis provides additional information beyond genomic analyses, which can improve understanding of cancer biology and patient stratification in diffuse GCs.
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•Mutation-phosphorylation correlation suggests possible signaling interplays in EOGCs•mRNA-protein correlation suggests genes with high association with patient survival•Integrated analysis of mRNA and protein data identified four subtypes•Phosphorylation data provide cellular signaling pathways underlying the subtypes
Mun et al. perform proteogenomic analysis of diffuse gastric cancers (DGC) in a young population, identifying that correlations of mRNA-protein abundance associate with survival and defining four subtypes of DGC. The associations of some subtypes with related pathways are identified mainly by the proteomic data.
In this work, we present a true 3D 128 Gb 2 bit/cell vertical-NAND (V-NAND) Flash product for the first time. The use of barrier-engineered materials and gate all-around structure in the 3D V-NAND ...cell exhibits advantages over 1 × nm planar NAND, such as small Vth shift due to small cell coupling and narrow natural Vth distribution. Also, a negative counter-pulse scheme realizes a tightly programmed cell distribution. In order to reduce the effect of a large WL coupling, a glitch-canceling discharge scheme and a pre-offset control scheme is implemented. Furthermore, an external high-voltage supply scheme along with the proper protection scheme for a high-voltage failure is used to achieve low power consumption. The chip accomplishes 50 MB/s write throughput with 3 K endurance for typical embedded applications. Also, extended endurance of 35 K is achieved with 36 MB/s of write throughput for data center and enterprise SSD applications.
A spiking neural network (SNN) inspired by the structure and principles of the human brain can significantly enhance the energy efficiency of artificial intelligence computing by overcoming the ...bottlenecks of the conventional von Neumann architecture with its massive parallelism and spike transmissions. The construction of artificial neurons is important for the hardware implementation of an SNN, which generates spike signals when enough synaptic signals are gathered. Because circuit‐level artificial neurons with comparator and reset circuits require considerable hardware area, intensive efforts are devoted in recent years for building artificial neurons at the device level for better area efficiency. Furthermore, artificial sensory neuron devices, which perform neural processing and sensing concurrently, have recently been developed in order to reduce the hardware cost and energy consumption of traditional sensory systems through in‐sensor computing. This review article surveys and benchmarks the recent progress of artificial neuron devices for neural processing and sensing. First, various artificial neuron devices are summarized, including single‐transistor neurons (1T‐neurons), memristor neurons, phase‐change neurons, magnetic neurons, and ferroelectric neurons. Next, cointegration technologies with artificial synaptic devices and artificial sensory neurons for in‐sensor computing are introduced. Finally, the challenges and prospects for developing artificial neuron devices are discussed.
The recent progress in artificial neuron devices for neural processing and sensing in a bioinspired spiking neural network is reviewed. Various artificial neuron devices with spiking operation, corresponding cointegration technologies with artificial synaptic devices, and recently emerging artificial sensory neurons for low‐power in‐sensor computing are addressed.
In this work, the authors report materials, fabrication strategies, and applications of biodegradable microsupercapacitors (MSCs) built using water‐soluble (i.e., physically transient) metal (W, Fe, ...and Mo) electrodes, a biopolymer, hydrogel electrolyte (agarose gel), and a biodegradable poly(lactic‐co‐glycolic acid) substrate, encapsulated with polyanhydride. During repetitive charge/discharge cycles, the electrochemical performance of these unusual MSCs is dramatically enhanced, following from the role of pseudocapacitance that originates from metal‐oxide coatings generated by electrochemical corrosion at the interface between the water‐soluble metal electrode and the hydrogel electrolyte. Systematic studies reveal the dissolution kinetics/behaviors of each individual component of the MSCs, as well as those of the integrated devices. An encapsulation strategy that involves control over the thickness, chemistry, and molecular weight of the constituent materials provides a versatile means to engineer desired functional lifetimes. Demonstration experiments illustrate potential applications of these biodegradable MSCs as transient sources of power in the operation of light‐emitting diodes and as charging capacitors in integrated circuits for wireless power harvesting.
An entirely biodegradable microsupercapacitor is successfully fabricated using water‐soluble metal electrodes, agarose gel electrolyte, and poly(lactic‐co‐glycolic acid) substrate. The development of biodegradable, high performance supercapacitors represents an important advance in the area of transient electronics, with potentially important consequences in technologies for biomedicine, environmental monitoring, sustainable electronics, and other areas.
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