Charge Pulse Research Articles

Experimental Study on Electrical Properties of Power Lithium-ion Battery

The paper studies the surface temperature rise and pulse charge/discharge capacity of batteries with different charge/discharge rates under different temperature conditions. The discharge performance and charge rate characteristics of an automotive lithium-ion battery were investigated. The battery discharge performance tests were conducted under different ambient temperatures and different charge rate conditions to obtain the battery charge voltage curve, charge capacity, and the temperature change pattern of the external surface of the battery during the charging process. Also, internal resistances of the battery cell were measured using the hybrid pulse power characteristic (HPPC). Experimental results show that the battery’s 10% to 90% DOD range shows the excellent pulse charging and discharging ability of the battery, and the temperature change of the battery is much higher at the beginning of the charging process and the end of the discharging process due to the influence of internal resistance.

Development of Novel Pulse Charger for Next‐Generation Batteries

Nowadays, battery‐powered direct current‐characterized loads are employed in domestic, commercial, and industrial applications. However, the current commercial or emerging new battery technologies are suffering from the problem of slow charging and early battery life degradation. This paper proposes a fast pulse charging method, which also prevents battery degradation. The research mainly focuses on the currently emerging aluminum batteries being charged using a pulse technique from the photovoltaic source. The pulse charge circuit is analyzed, simulated, designed, and tested with a rechargeable electrochemical cell as a load. The simulations are performed using MATLAB/Simulink software. The laboratory model is implemented with the Arduino Mega2560 board‐based pulse width modulation technique. The proposed charger circuit is tested with two different charging methods using a pulse technique through continuous conduction mode used to test the Al battery. The results showed a reduction in total charging time, and the battery's overall performance was immensely improved. The charge and discharge studies of the battery have been carried out using a biologic electrochemical station.

Simplified Electrochemical Approaches for Quality Determination of the Wetting Process in Lithium‐Ion Cell Production

Electrolyte filling and wetting are safety‐relevant and time‐ and cost‐intensive processes in lithium‐ion cell production, and are hence critical process steps. Currently, only limited measurement technologies are available that would be suitable for inline monitoring and quality assurance of these process sequences. Herein, two promising electrochemical approaches for monitoring electrolyte wetting are presented, which can be utilized in low‐cost measurement devices. Starting from the introduction of a simplified impedance approach with a straightforward data evaluation, a direct current‐based method is introduced that does not require impedance equipment, and can thus be performed with standard battery cyclers. First, the extended applicability of the simplified impedance measurement is demonstrated by examining the dependence of experimental impedance results on varying electrolyte volumes, also including insufficient amounts. Subsequently, the impedance approach is transferred into the direct current method. The latter mimics impedance signals by utilizing repetitive direct current charge and discharge pulses, which are used to determine the batteries’ internal resistance during the electrolyte wetting. Both introduced approaches yield comparable results and allow the inline monitoring of the electrolyte wetting with basic equipment and with no need for demanding data evaluation.

Analisis Visual Media Promosi Poin Festival 2022 Dalam Meningkatkan Loyalitas Konsumen

Telkomsel Poin is the retention Telkomsel subscriber for all having Poin from charging pulse and data package prepaid customer and Halo. Telkomsel make various whether they are monthly loyalty program, weekly and thematic. In the meantime Telkomsel Poin make special program Poin Festival 2022 after govermen issued a policy about the latest PPKM held in offline in Summarecon Mal Serpong and other digital campaign. Poin Festival 2022 campaign poin covering several important way as lucky draw, cuan hepi, dan mendadak Hepi. Concept of creative implementation in combined with the modern trend classic festival which are reflected in the use of composition color, texture and attractive form.The vibrant color using color and texture to the shape of objects.Textures that are used as gradation by various forms as oval, box, of images and information as a barrier between messages. Media campaign assets such as through digital media channel, the digital media placement Google. The goal to cover all segment by using the method story, how, audience, reach and excellence.

Calibrated Electrochemical Impedance Spectroscopy and Time‐Domain Measurements of a 7 kWh Automotive Lithium‐Ion Battery Module with 396 Cylindrical Cells

AbstractA 7 kWh automotive battery module with 396 interconnected cells was tested with electrochemical impedance spectroscopy (EIS) and time‐domain pulsing over 260 charge‐discharge cycles. An EIS calibration workflow was developed for low complex impedance values in a frequency range of 1 kHz to 50 mHz. Significant corrections on the resistance and the reactance were obtained from the calibration, particularly at frequencies above 100 Hz. Equivalent circuit parameters were extracted from the EIS spectra and the pulse response and investigated with respect to the cycle number and state‐of‐charge (SoC). Fit parameters were robustly extracted including Rsol, Rct, and L from EIS, and R0, τ1 and τ2 from time‐domain pulsing. The ohmic resistance decreased over the cycling number indicating an enhanced wetting of the electrodes. Charge transfer resistance Rct showed a monotonic increase over the cycles related to cell ageing. From the charge and discharge pulses, the ohmic resistance R0 was determined from the instantaneous voltage step of the recovery pulse, while the two time constants τ1 and τ2 correspond to the slower exponential recovery phase. R0 from the time‐domain showed a similar trend as Rsol plus a contribution of Rct from EIS. Overall, we show that calibrated EIS and time‐domain pulsing are efficient methods to gain insights into the electrochemical processes related to different SoCs and the cycling ageing of battery modules and packs.

State of Health Estimation for Smart Batteries using Transfer Learning with Data Cleaning

Smart battery with optimized pulsed current produced by the bypass is one prospective technology to prolong the service life of the batteries in electric vehicles. The accurate and reliable state of health (SOH) estimation is one significant process before the decision of the control. This paper proposes a proper solution for battery SOH estimation that can be applied to both constant and pulsed current charging scenarios. Specifically, a data cleaning process is proposed for preprocessing the fluctuated measurement, while retaining the main aging information. From the pre-processed data under different charging profiles, four SOH features are extracted, and the correlation coefficients prove their effectiveness with both constant current and pulsed currents. Later, a transfer learning-based model is developed which shows improved accuracy of the SOH estimations under pulsed current scenarios. Finally, experiments have been conducted to verify the proposed method. In the case of model retraining using only the first 10% of unseen data, satisfactory results can be obtained (the error is less than 2.626%). By increasing the data for model retraining to 20%, a fitted coefficient of larger than 0.994 between the estimations and real values is obtained, resulting in a low estimation error of less than 0.8%.

Performance of real-time neutron/gamma discrimination methods

Nuclear security usually requires the simultaneous detection of neutrons and gamma rays. With the development of crystalline materials in recent years, Cs2LiLaBr6 (CLLB) dual-readout detectors have attracted extensive attention from researchers, where real-time neutron/gamma pulse discrimination is the critical factor among detector performance parameters. This study investigated the discrimination performance of the charge comparison, amplitude comparison, time comparison, and pulse gradient methods and the effects of a Sallen–Key filter on their performance. Experimental results show that the figure of merit (FOM) of all four methods is improved by proper filtering. Among them, the charge comparison method exhibits excellent noise resistance; moreover, it is the most suitable method of real-time discrimination for CLLB detectors. However, its discrimination performance depends on the parameters {t}_text{s}, {t}_text{m}, and {t}_text{e}. When {t}_text{s} corresponds to the moment at which the pulse is at 10% of its peak value, {t}_text{e} requires a delay of only 640–740 ns compared to {t}_text{s}, at which time the potentially optimal FOM of the charge comparison method at 3.1–3.3 MeV is greater than 1.46. The FOM obtained using the {t}_text{m} value calculated by a proposed maximized discrimination difference model (MDDM) and the potentially optimal FOM differ by less than 3.9%, indicating that the model can provide good guidance for parameter selection in the charge comparison method.

Development of Pulse Charger for Electric Vehicle Batteries

The issue of slow charging and early battery life deterioration affects emerging new battery technologies. This study suggests a quick pulse charging technique that guards against battery deterioration and provides sustainable operation. The research primarily focuses on newly developed batteries charged from a solar source utilizing a pulsed approach. ANSYS or MATLAB/Simulink are used for the different simulations. The charger circuit comprises the Photovoltaic panel, transformer, a passive element like a capacitor, voltage regulator, and bridge rectifier. An optocoupler, an isolation circuit, and a DSP controller comprise the control circuit. The charger circuit receives power directly from the solar panel, and the duty ratio is configured in the Arduino software, which controls the output voltage.

Optimization of Design Method and Experiment of A Repetition Pulse Charging HIA-CCPS

Due to the advantage of high-power density, high energy storage density and fast repetition pulse charging ability, homopolar inductor alternator (HIA) has been successfully applied in the capacitor charging power supply (CCPS) system, leading to a new capacitor charging power supply (HIA-CCPS) in recent years. To obtain a compact HIA-CCPS with high performances of light weight, small size, high repetition pulse output ability and so on, it is still of great necessity to develop quantitative analysis from alternators to the pulse load such as capacitors. Unfortunately, many researchers only focus on the alternator design or use a single charging process with constant speed instead of the repetition charging dynamic process with a large speed change for simplifying analysis. As a result, parameters' influence between alternators and others in the system is not clear, it is not easy to find out a system-wide optimal scheme. In this text, a comprehensive design method for HIA-CCPS with repetition pulse charging is proposed. Firstly, a simplified model is presented to analyze the influence of different parameters. The repetition pulse charging characteristics of HIA is investigated. After that, a novel design method of repetition pulse charging is given, and an excitation control strategy during the charging is put forward to ensure the charging time remains almost constant between each charging time. Finally, a platform of HIA-CCPS is developed and experiments are carried out. The experiment results indicate that the proposed method is very helpful for a repetition charging HIA-CCPS to develop the optimization design.

Afterpulse measurement of JUNO 20-inch PMTs

In this study, we present the large photomultiplier tube (PMT) afterpulse measurement results obtained from the Jiangmen underground neutrino observatory (JUNO) experiment. A total of 11 dynode-PMTs (R12860) from the Hamamatsu company (Hamamatsu Photonics K.K. (HPK)) and 150 micro-channel plate PMTs (MCP-PMTs, GDB-6201) from the NNVT company (North Night Vision Technology Co., Ltd. (NNVT)) were tested. Subsequently, an afterpulse model was built according to the afterpulse time distribution and the probability of occurrence for these two types of PMTs. The average ratio of the total afterpulse charge with a delay between 0.5 \(\upmu\)s and 20 \(\upmu\)s to the primary pulse charge is \(\sim\) 5.7% (13.2%) for the tested MCP-PMTs (dynode-PMTs). The JUNO experiment will deploy 20,012 20-inch PMTs; this study will benefit detector simulation, event reconstruction, and data analysis regarding the JUNO experiment.

Energy-dense anode-free rechargeable lithium metal batteries based on thick cathodes and pulse charging strategies

In combination with a thick cathode and pulse charging strategies, anode-free lithium metal batteries demonstrated reduced polarization at 5 mA cm−2 and a capacity retention of 79.4% after 50 cycles.

SpacePix2: SOI MAPS detector for space radiation monitoring

The SpacePix2 monolithic active pixel sensor (MAPS) is a novel ASIC for space radiation monitoring designed in a 180 nm SOI CMOS technology. The active sensor area is 3.84 × 3.84 mm2, pixel matrix is arranged as a 64 × 64 array with 60 µm pitch. The pixel front-end amplifier signal range is 2–80 ke−, extended up to 30 Me− using a backside channel. Diodes integrated in the handle wafer in each pixel are biased at −150 V. Impinging particle generates a charge pulse converted to voltage pulse by charge sensitive amplifier (CSA). Maximum voltage memorized by the peak detector hold (PDH) circuit is digitized using on-chip 10-bit asynchronous column SAR ADCs. Two readout interfaces are available, 400 MHz LVDS and 50 MHz SPI. Total power consumption is 43 mA from a 1.8 V power supply. The ASIC has been tested in space in low Earth orbit (LEO) and sample data are shown.

Rapid Prediction of Retired Ni-MH Batteries Capacity Based on Reliable Multi-Parameter Driven Analysis

In order to solve the problems of long-time consumption and high energy consumption in existing capacity detection methods of retired Ni-MH batteries, a fast and reliable capacity prediction method for retired Ni-MH batteries by multi-parameter driven analysis was proposed in this paper. This method mainly obtains several parameters through short-time measurement and pulse rapid nondestructive testing. Then, Pearson correlation coefficient and KS-test were used to analyze the correlation between the two parameters and verify the same distribution. Finally, SVR was used to predict the battery discharge capacity. The results show that the volume expansion thickness difference Δd, AC internal resistance R, terminal voltage U of the battery, charge and discharge polarization internal resistance Rf1 and Rf2 and pulse charging power P2 of the battery are strongly negatively correlated with the discharge capacity, and these characteristic parameters can effectively and reliably reflect the internal structural characteristics of the battery. Additionally, the mean relative error of the established capacity model is 5.87%, and the lowest error is 1.32%. The prediction effect is good, which provides a certain reference value for the subsequent consistent sorting method.

Research on Compact Nanosecond High-voltage Pulse Source

With the application of pulse power technology in the fields of biomedical research, portable pulse source, and electromagnetic pulse radiation, the research of pulse sources puts forward new requirements such as compact structure, long pulse width, and high voltage resistance. The traditional pulse source has a long pulse period and short pulse width, which cannot meet the requirements of the high repetition frequency and high output power. In this paper, a nanosecond high-voltage pulse source is designed, which consists of a primary power supply, a pulse charging system, and a pulse shaping system. The DC power charges the Marx generator, while the Marx generator output is shaped by short-circuit sharpening switches. In this paper, PSpice simulation software is used to simulate the results: the pulse period is 1.4ns and the peak-to-peak voltage is 210kV.

Significantly Enhanced Energy Storage Performance in High Hardness BKT-Based Ceramic via Defect Engineering and Relaxor Tuning.

Hybrid electric cars and pulsed power technologies have increased the demand for capacitors with high energy density, wide temperature stability, high operating voltage, and good mechanical qualities. In this work, (1 - x) (0.6Bi0.5K0.5TiO3-0.4BiFeO3)-x(Na0.4Sm0.2NbO3) ((1 - x) (BKTBF)-xNSN) relaxor ceramics were prepared by constructing morphotropic phase boundary (MPB) combined with oxygen vacancy defect engineering. It is worth noting that the 0.6BKT-0.4BFO ceramics at MPB have a high Pmax ∼ 60 μC/cm2. The ultra-hard (HV = 10.7 GPa) BKTBFO-0.16NSN relaxor ferroelectric ceramic achieves a high Wrec of 6.52 J/cm3, a working temperature of 20-120 °C, and a working frequency of 1-1000 Hz. Additionally, the BKTBFO-0.16NSN ceramic demonstrates comprehensive pulse charge-discharge performance (Imax = 17.2 A, CD = 546.7 A/cm2, PD = 54.7 MW/cm3, and t0.9 = 59 ns) and excellent stability (25-125 °C and 104 charge-discharge cycles). This study offers a novel approach for the practical implementation of high-performance pulse capacitors, which will undoubtedly stimulate further research and development of high-Pmax energy storage dielectrics (such as BNT, BKT, and BFO).

Pulsed Current Boosts the Stability of the Lithium Metal Anode and the Improvement of Lithium-Oxygen Battery Performance.

Lithium-oxygen batteries have received extensive attention due to their high theoretical specific capacity, but problems such as high charging overpotential and poor cycling performance hinder their practical application. Herein, a pulsed current, which merits its relaxation phenomenon, is applied during the charging cycle to address the abovementioned problems. Pulsed charging can not only reduce the charging overpotential, but also control the mass transfer and distribution of lithium ions. As a result, the uniform deposition of lithium ions on the anode surface is realized, the repeated rupture and formation of the solid electrolyte interphase is reduced, and the growth of the lithium dendrites is successfully suppressed, thereby achieving the purpose of protecting lithium metal from excessive consumption. When the pulsed charging duty ratio (Ton/Toff) is 1:1, after 25 cycles, the lithium-oxygen battery anode still presents a relatively flat and dense deposition surface, which is obviously better than the loose and rough surface after normal cycling. In addition, the protective effect of pulsed charging on the lithium metal anodes of lithium-oxygen batteries is also verified by the construction of other lithium-based batteries.

Effect of Pulsed Current on Charging Performance of Lithium-Ion Batteries

The pulsed current has been proposed as a promising battery charging technique to improve the charging performance and maximize the lifetime for lithium-ion (Li-ion) batteries. However, the effect of the pulsed current charging is inconclusive due to the changeable current mode and conditions. This article systematically investigates the effect of various pulsed current charging modes, i.e., positive pulsed current mode, pulsed current-constant current mode, negative pulsed current mode, alternating pulsed current mode, sinusoidal-ripple current mode, and alternating sinusoidal-ripple current mode on battery performance. Moreover, a comprehensive analysis of the frequency impact on the quality of the current mode is performed. The current modes in this work are evaluated considering the maximum rising temperature, discharging capacity, and charging speed according to experimental results. Furthermore, this work provides guidance for developing pulsed current charging strategies to satisfy future charging requirements.

Effect of temperature on the high-rate pulse charging of lithium-ion batteries

Based on the residual energy recovery in the electromagnetic emission scenario, the 30C pulse charging cycle experiments of LiFePO 4 batteries customized for electromagnetic emission at different charging temperatures were carried out to study the influence of charging temperature on battery aging. By adjusting the ambient temperature, heat dissipation conditions, and rest time, we studied the battery aging process at the average charging temperatures of 16 °C, 21 °C, 26 °C, 30 °C and 35 °C. Experimental results show that increasing charging temperature can significantly delay battery aging and prolong battery cycle life. In addition, when the average charging temperature is lower than 30 °C, the battery shows nonlinear aging; when the average charging temperature is higher than 30 °C, the battery shows linear aging in the early stage of cycling and nonlinear aging at the end of the cycle. The results of differential capacity analysis (DCA) show that the loss of lithium inventory is the primary aging mode of the battery and did not change with charging temperature. The aging mechanism of the battery under high-rate pulse charging was studied through multiscale post-test analysis. Analysis results showed that with the increase of charging temperature, the area of lithium-plating area decreases, and the thickness of SEI film increases. It can be inferred that when the average charging temperature is lower than 30 °C, lithium plating is the primary aging mechanism of the LiFePO 4 battery customized for electromagnetic emission. When the average charging temperature is higher than 30 °C, the growth of SEI film is the primary aging mechanism of the battery.

Multichannel High Voltage Pulsed Generator for Electro-Discharge Technologies

The design and test results of the multichannel high-voltage (HV) pulse-periodic generator, designed for materials crushing, are presented. The generator scheme is based on pulsed charging of high-voltage capacitive storage from low-voltage capacitive storage through a step-up transformer. The HV capacitive energy storage made in the form of four parallel-connected branches with the capacity of each branch is of 12.5 nF. Each branch of the storage feeds its own discharge channel in the crushing chamber. Tests have shown that the generator allows the implementation of four discharge channels simultaneously in the crushing chamber. The following output pulse parameters of the generator were achieved: output voltage up to 100 kV, voltage rise time of ~60 ns, half-period of the discharge current of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 0.5~\mu \text{s}$ </tex-math></inline-formula> , and current amplitude of ~5 kA per channel. The possibility of increasing productivity without increasing specific energy consumption during the transition from single-channel to multichannel mode of the high-voltage electric pulse (HVEP) crushing has been studied, as well as a comparison of the fractional composition of crushed products in both modes.

Pulsed Charging Protocols with Non-Zero Relaxation Time for Lithium-Ion Batteries

Lithium-ion batteries are commonly charged following the constant current -constant voltage (CC-CV) protocol. Current flow during charging implies an equivalent ionic flow through the battery materials. Intercalation and de-intercalation of Li+ are accompanied by concentration gradients that are reflected by the rise in the cells’ potentials that is required to maintain the constant current during the CC regime. In this work, two new pulsed charging protocols were tested. Firstly, a square current pulse is applied to the cell until the cut-off voltage is reached, followed by a pulsed square voltage protocol (PV). The second methodology keeps the same current pulse, however, after the limiting voltage was reached, the pulsing regime consisted in alternating between a maximum voltage value and a minimum, non-zero, constant current value. Different voltage pulse widths and frequencies were tested, in order to study the maximum electrodes’ capacity, the time required to reach that capacity, the contribution of each individual step (i.e. PC and PV) to the total electrodes’ capacity, and the thermal variations for each. The second pulsing mode produced capacity values 7%–8% higher than in the classical CC–CV protocol, and in charging times periods from 5%–25% faster, without compromising the batteries’ cycle life.