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An ultra-low quiescent current output-capacitor-less low dropout (OCL-LDO) regulator for power-sensitive applications is proposed in this paper. To improve the gain of the OCL-LDO feedback loop, the error amplifier employs a combination of a cross-coupled input stage for boosting the equivalent input transconductance and a negative resistance technique to improve the gain. Meanwhile, in order to address the issue of transient response of the ultra-low quiescent current OCL-LDO, a sub-threshold slew-rate enhancement circuit is proposed in this paper, which consists of a transient signal input stage and a slew-rate current increase branch. The proposed OCL-LDO is fabricated in a 0.18 μ m CMOS process with an effective area of 0.049 mm2. According to the measurement results, the proposed OCL-LDO has a maximum load current of 100 mA and a minimum quiescent current of 640 nA at an input voltage of 1.2 V and an output voltage of 1 V. The overshoot and undershoot voltages are 197 mV and 201 mV, respectively, and the PSR of the OCL-LDO is −72.4 dB at 1 kHz when the load current is 100 μ A. In addition, the OCL-LDO has a load regulation of 7.6 μ V/mA and a line regulation of 0.87 mV/V. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) hold great potential for grid‐scale energy storage systems, owing to their intrinsic safety and low cost. Nevertheless, their industrialization faces challenges of severe Zn dendrites and parasitic reactions. In this study, sulfonated cellulose separator (denoted as CF‐SO3) with low thickness, exceptional mechanical strength, and large ionic conductivity is developed. Benefiting from the electrostatic repulsion between ─SO3− functional groups and SO42− anions and the strongly interaction between ─SO3− and Zn2+ cations, the migration of SO42− anions can be restricted, the 2D diffusion of Zn2+ ions at the surface of Zn electrode can be suppressed, and the desolvation of hydrated Zn2+ ions can be promoted. Concurrently, the homogeneous nanochannels within CF‐SO3 separator can ensure uniform electric field and Zn2+ ion flux. With these benefits, the CF‐SO3 separator enables Zn//Zn cells to run stably for 1200 h at 4 mAh cm−2 by facilitating oriented and dendrite‐free Zn deposition. Under a large depth of discharge of 68.3%, a life span of 400 h can still be achieved. Additionally, the reliability of CF‐SO3 separator is confirmed in Zn//MnO2 and Zn//H11Al2V6O23.2 full batteries with high mass loading conditions. This work provides valuable guidance for the advancement of high‐performance separators of AZIBs. [ABSTRACT FROM AUTHOR]

LiNi0.5Mn1.5O4 (LNMO) with a spinel crystal structure presents a compelling avenue towards the development of economic cobalt-free and high voltage (∼ 5 V) lithium-ion batteries. Nevertheless, the elevated operational voltage of LNMO gives rise to pronounced interfacial interactions between the distorted surface lattices characterized by Jahn–Teller (J–T) distortions and the electrolyte constituents. Herein, a localized crystallized coherent LaNiO3 and surface passivated Li3PO4 layer is deposited on LNMO via a one-step calcination process. As evidenced by transmission electron microscopy (TEM), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and density functional theory (DFT) calculation, the epitaxial growth of LaNiO3 along the LNMO lattice can effectively stabilize the structure and inhibit irreversible phase transitions, and the Li3PO4 surface coating can prevent the chemical reaction between HF and transition metals without sacrificing the electrochemical activity. In addition, the ionic conductive Li3PO4 and atomic wetting inter-layer enables fast charge transfer transport property. Consequently, the LNMO material enabled by the lattice bonding and surface passivating features, demonstrates high performance at high current densities and good capacity retention during long-term test. The rational design of interface coherent engineering and surface coating layers of the LNMO cathode material offers a new perspective for the practical application of high-voltage lithium-ion batteries. [ABSTRACT FROM AUTHOR]