Charge-discharge Cycling Tests Research Articles

Pseudocapacitive properties of nickel oxide nanoparticles synthesized via ultrasonication approach

Here, nickel oxide (NiO) nanoparticles are prepared via an ultrasonication approach and tested for the pseudocapacitance performance. The crystalline structures, functional groups, and morphology of NiO nanoparticles are investigated using various experimental tools such as XRD, FT-IR, FESEM, and HRTEM respectively. Cyclic voltammetry (CV), galvanostatic charge-discharge cycling test, and electrochemical impedance spectroscopic (EIS) measurements were utilized to determine the pseudocapacitive properties of the NiO nanoparticles. Noticed high specific capacitance (423 F g−1) at 0.5 mA cm−2 current density and in addition achieved good capacitance retention (93%) even after continuous 2000 cycles illustrate excellent electrochemical stability of sonochemically prepared NiO nanoparticles compared to other preparation procedures.

Development of Li10GeP2S12-Type Solid Electrolytes with Electrochemical Stability to Li Metal Anode

Solid-state Li-ion battery promises potentially high-power characteristics, although increase in energy density remains as an issue to be solved.1,2 Therefore solid electrolytes that possess electrochemical stability to Li metal electrode as well as high ionic conductivity are urgently demanded. This study synthesized solid electrolytes using Li10GeP2S12(LGPS),3 a supersonic conductor showing Li ion conductivity over 10−2 S cm−1, as a structural template; we performed material search for LGPS-derivatives in the Li–M–P–S–O–X (M = Ge, Si, Sn; X = F, Cl, Br, I) system in order to elucidate effects of doped- anion/cation towards the stability to Li metal electrode. We discovered various LGPS-type electrolytes through optimization of synthesis condition for each chemical composition. For the Li–M–P–S–X system, heating at 400–550°C is required, for Li–P–S–O–X at 200–280°C, and for Li–Si–P–S–O at 950–1000°C, respectively. The synthesized solid electrolytes were characterized by structure analysis based on diffraction data and AC impedance method. Electrochemical stability for electrolytes was evaluated by charge–discharge cycling tests of solid-state cell, in which the synthesized electrolyte, Li metal, and the mixture of LiNbO3-coated-LiCoO2 and LGPS was used as a separator, anode, and cathode, respectively. The retention rate of discharge capacity was used as an indicator for evaluating stability towards Li metal. The effects of oxygen doping were clarified in the Li–M–P–S–O and Li–P–S–O systems. The cell using Li9.42Si1.02P2.1S9.96O2.04 or Li3.2PS3.7O0.3 respectively showed retention rate of more than 98% whereas Li–M–P–S cells showed less than 20% after 5th cycle.4 However, these oxygen-doped electrolytes suffer from lower conductivity on the order of 10−4 S cm−1. These results indicate oxygen doping improves electrochemical stability but at the cost of decrease in conductivity. On the other hand, the Li–P–S–X system showed 99% capacity retention after 5th cycle as well as a high conductivity of 4×10−3 S cm, suggesting doping halogen elements is a promising technique for achieving a better balance between stability and conductivity for LGPS-type electrolytes. References Kato, Y.; Hori, S.; Saito, T.; Suzuki, K.; Hirayama, M.; Mitsui, A.; Yonemura, M.; Iba, H.; Kanno, R., High-power all-solid-stae batteries using sulfide superionic conductors. Nature Energy 2016, 1, (16030).Janek, J.; Zeier, W. G., A solid future for battery development. Nature Energy 2016, 1 (9).Kamaya, N.; Homma, K.; Yamakawa, Y.; Hirayama, M.; Kanno, R.; Yonemura, M.; Kamiyama, T.; Kato, Y.; Hama, S.; Kawamoto, K.; Mitsui, A., A lithium superionic conductor. Nat. Mater. 2011, 10, 682-686.Hori, S.; Suzuki, K.; Hirayama, M.; Kato, Y.; Kanno, R., Lithium Superionic Conductor Li9.42Si1.02P2.1S9.96O2.04 with Li10GeP2S12-Type Structure in the Li2S–P2S5–SiO2 Pseudoternary System: Synthesis, Electrochemical Properties, and Structure–Composition Relationships. Frontiers in Energy Research 2016, 4 (38).

Structural and electrochemical studies of LiNixCo(1-x)VO4 (x = 0.2, 0.8) cathode materials for rechargeable lithium batteries

A family of mixed LiNixCo(1-x)VO4 (x = 0.2, 0.8) cathode materials has been synthesized using the sol–gel method. The thermal behavior of the materials has been examined by thermogravimetric (TG) analysis. The Rietveld refinement of powder X-ray diffraction showed the structure with $$ Fd\overline{3}m $$ (227) space group. Surface analysis was performed using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Analysis of Raman spectra reveals the local environment model including VO4 tetrahedra, (Ni,Co)O6, and LiO6 octahedra as vibrational local units. X-ray photoelectron spectroscopy (XPS) studies on synthesized powder indicate that the oxidation states of nickel, cobalt, and vanadium are + 2, + 3 and + 5, respectively. Charge–discharge cycling tests were carried out to study the performance of the cathode materials.

A 10kW Class Ti/Mn Redox Flow Battery

Large-scale energy storage systems play an important role in the effective use of renewable energy such as wind and solar power. Redox flow batteries (RFBs) have attracted a great deal of attention because of high-speed response, the independent design of power and energy, and advantages in safety. RFBs consist of tanks of electrolyte which store chemical energy and electrochemical cells which reversibly convert chemical energy to electricity. All-vanadium RFBs are widely used as the most mature technology while other various redox species can also be utilized as the electrolyte.Among redox species applicable in aqueous solution, we have reported an electrolyte of titanium and manganese. The discharged state consists of Ti (IV) and Mn (II), both of which are widely available from abundant and low-cost resources. An energy density of 23.5 kWh/m3 is achievable due to the two-electron reaction of manganese on the positive side [1]. Main issues of the Ti/Mn RFB are the precipitation of MnO2 over time in the positive electrolyte and its low power density. As for the precipitation, a systematic research on the effect of mixing Ti (IV) into the positive electrolyte revealed that Ti (IV) ions change the morphology and the crystal structure of MnO2 as well as the electrochemical property of the positive electrolyte [2]. The other issue of low power density can be overcome by thermal treatment of carbon electrodes [3]. Moreover, the low permeability of ions in the Ti/Mn electrolyte contributes to the high coulombic efficiency even when a thin membrane is used. We have reported that the combination of a heat-treated carbon electrode and a thin membrane led to the highest energy efficiency, which was 84.3% with a current density of 200 mA/cm2 [4].In this work, long-term cycle test was performed in a scaled-up system in order to further investigate the reliability of Ti/Mn RFBs. The evaluation system was designed to be approximately 10 kW×1h. In charge-discharge cycle tests, it was confirmed that the cell performance was stable over 100 cycles. A stable energy density over 14 kWh/m3 was successfully confirmed with a current density of 200 mA/cm2. The coulombic efficiency remained over 99%. The characteristics of this Ti/Mn RFB will be discussed in details in the presentation.

Transformerless Bidirectional PWM Converter Integrating Voltage Multiplier-Based Cell Voltage Equalizer for Series-Connected Electric Double-Layer Capacitors

In the traditional energy storage systems consisting of series-connected energy storage cells such as electric double-layer capacitors (EDLCs), not only a bidirectional pulsewidth modulation (PWM) converter but also a cell voltage equalizer is required. The system is prone to complexity as two converters (i.e., the bidirectional converter and cell voltage equalizer) are separately necessary. This paper proposes the transformerless bidirectional PWM converter integrating the voltage multiplier-based cell voltage equalizer. An inductor in a conventional bidirectional PWM converter is replaced with series-connected inductors in the proposed converter in order to generate square-wave voltage with an arbitrary amplitude, by which the voltage multiplier is driven. The charge–discharge cycling test for nine EDLCs connected in series was performed using the proposed integrated converter from a voltage-imbalanced condition. The voltage imbalance was gradually eliminated during charge–discharge cycling, demonstrating the integrated functions.

Low-temperature synthesis of LiCoO2 with eutectic of lithium precursors via the solid-state reaction method

ABSTRACTLithium cobalt oxide powders have been prepared via the solid-state reaction method at lower temperatures (650 and 750°C) and in a shorter time (2 h). The eutectic effects of LiOH· H2O and Li2CO3 salts on the formation of LiCoO2 was investigated. The effects of the molar ratio of LiOH·H2O to Li2CO3, the sintering temperature and the molar ratio of Li/Co on the physicochemical properties of LiCoO2 powders were examined, especially, by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and charge-discharge cycling tests. LiCoO2 prepared at 750°C and 2 h with a molar ratio (9:1) between these of LiOH·H2O and Li2CO3 showed the best electrochemical properties (discharge capacity 98.3 mAhg−1 and capacity retention 80.7% after 50 cycles at 1C).

Effect of negative/positive capacity ratio on the rate and cycling performances of LiFePO4/graphite lithium-ion batteries

Abstract The influence of the capacity ratio of the negative to positive electrode (N/P ratio) on the rate and cycling performances of LiFePO4/graphite lithium-ion batteries was investigated using 2032 coin-type full and three-electrode cells. LiFePO4/graphite coin cells were assembled with N/P ratios of 0.87, 1.03 and 1.20, which were adjusted by varying the mass of the graphite negative electrode. Three-electrode cells were also assembled with similar N/P ratios to understand the potential variations of the positive and negative electrodes. The cycling performances of the coin cells were evaluated by repeating the charge-discharge cycle 5000 times (1 C-rate for the 1st–1000th cycle and 2 C-rate for the 1001st–5000th cycle) at cell voltages of 2.5–4.2 V, during which their rate performances were intermittently evaluated (0.1–10 C-rate). Prior to the charge-discharge cycling test, the highest cell specific capacity was obtained from the lowest N/P ratio of 0.87. The coin cell with the highest N/P ratio of 1.20 exhibited the highest capacity retention of 86.5% at 1 or 2 C-rate in the 5000 cycle test. The results obtained using the three-electrode cells showed that the higher N/P ratio elevated the working potential ranges of the positive and negative electrodes. The lower N/P ratio led to deeper Li-ion intercalation for the negative electrode, lowering the potential of both the positive and negative electrodes. The lower N/P ratio was beneficial for achieving full performances from the initial service, but caused larger capacity fading due to the aging by cycling. The higher N/P ratio rather restricted the performances at the initial service, which was useful to prevent the cycling-derived capacity fading. The lowering of rate performance owing to the charge-discharge cycling, particularly at the high current densities of 5 and 10 C-rates, was enhanced by the decrease in the N/P ratio.

Tuning morphology and conductivity in two-step synthesis of zinc-cobalt oxide and sulfide hybrid nanoclusters as highly-performed electrodes for hybrid supercapacitors

We reported a facile two-step hydrothermal procedure to prepare zinc-cobalt oxide and sulfide hybrid nanoclusters (ZCOSH NCs), initialized by the synthesis of metal oxides and followed by the partial substitution of oxygen with sulfur. Benefiting from their morphological features and partial substitution with sulfur, both the electrical conductivity and further the actual specific capacitance of ZCOSH NCs were apparently improved compared to zinc-cobalt binary oxide nanosheets (ZCO NSs). Moreover, its cycling stability has also been significantly enhanced. Its excellent specific capacitance achieved 2176.7 F g−1 at 1 A g−1, which was six times larger than ZCO NSs (367.2 F g−1 at 1 A g−1). Moreover, a hybrid supercapacitor was assembled using ZCOSH NCs as its positive electrode and the activated carbon as its negative electrode. This hybrid supercapacitor device presented a higher specific capacitance value of 116.3 F g−1 at 1 A g−1 with corresponding specific energy of 41.4 W h kg−1 at a specific power of 801.3 W kg−1, and a superior cycling stability after 3000 charge-discharge cycling tests. This study confirmed the feasible and unique synthesis approach to balance the higher capacitance of oxides and the higher electric conductivity of sulfides within this binary ZCOSH NC.

Effect of organophosphorus compound additives for thermal stability on the positive electrolyte of a vanadium redox flow battery

3-Aminopropylphosphonic acid (3APPA) and sodium 3-phosphonopropionate (3PPA-Na) are investigated as organophosphorus compound additives in a positive electrolyte of a vanadium redox flow battery (VRFB) to improve its thermal stability. The precipitation-inhibiting effects of 2 M vanadium electrolytes, including the above additives, are studied by UV–Vis spectroscopy, Raman spectrophotometry, cyclic voltammetry (CV), and charge–discharge cycling test in the redox flow battery. The UV–Vis spectroscopy and Raman spectrophotometry show that no new substances formed in both the V(IV) and V(V) electrolytes with 3APPA and 3PPA-Na additives. Cyclic voltammetry (CV) shows the electrochemical activity and reversibility of the electrolytes with and without the additives. In the flow cell, the discharge capacity retention values in the positive electrolyte after 100 cycles at 45 °C are 56.7, 64.7, and 48.4% in 3PPA-Na, 3APPA, and without the additives, respectively. These results indicate that the 3APPA additive increases the discharge capacity retention to more than 16% compared to the electrolyte without the additive due to the retardation of precipitation at the high temperature.

Branched sulfonated polyimide/functionalized silicon carbide composite membranes with improved chemical stabilities and proton selectivities for vanadium redox flow battery application

Silicon carbide (SiC) was pretreated and functionalized by using α, ω-diaminopropyl polydimethylsiloxane (PDMS) to obtain a novel inorganic filler SiC (PDMS). Then, a series of branched sulfonated polyimide/SiC (PDMS) (bSPI/SiC (PDMS)) composite membranes with different contents of SiC (PDMS) were fabricated for vanadium redox flow battery (VRFB) application. Fourier transform infrared spectra, X-ray diffraction, and field emission scanning electron microscope demonstrate the successful preparation of SiC (PDMS) and bSPI/SiC (PDMS) membranes. The thermogravimetric analysis shows that bSPI/SiC (PDMS)-1.5% membrane has better thermal stability than pure bSPI, bSPI/SiC-1.5%, and Nafion 117 membranes. The ex situ chemical stability test results show that bSPI/SiC (PDMS)-0.5–2.5% composite membranes have better chemical stabilities than pure bSPI membrane. The physicochemical properties of bSPI/SiC (PDMS) membranes, including water uptake, swelling ratio, ion exchange capacity are investigated. Thereinto, bSPI/SiC (PDMS)-1.5% membrane has the highest proton selectivity (S: 2.99 × 105 S min cm−3) and was chosen as an optimum VRFB membrane. And the VRFB assembled with bSPI/SiC (PDMS)-1.5% membrane exhibits better battery performance than that assembled with Nafion 117 membrane during 500-time cyclic charge–discharge test at 20–60 mA cm−2. Above results indicate that as-optimized bSPI/SiC (PDMS)-1.5% membrane has great potential for VRFB application.

Highly-Stable Li₄Ti₅O12 Anodes Obtained by Atomic-Layer-Deposited Al₂O₃.

LTO (Li4Ti5O12) has been highlighted as anode material for next-generation lithium ion secondary batteries due to advantages such as a high rate capability, excellent cyclic performance, and safety. However, the generation of gases from undesired reactions between the electrode surface and the electrolyte has restricted the application of LTO as a negative electrode in Li-ion batteries in electric vehicles (EVs) and energy storage systems (ESS). As the generation of gases from LTO tends to be accelerated at high temperatures (40–60 °C), the thermal stability of LTO should be maintained during battery discharge, especially in EVs. To overcome these technical limitations, a thin layer of Al2O3 (~2 nm thickness) was deposited on the LTO electrode surface by atomic layer deposition (ALD), and an electrochemical charge-discharge cycle test was performed at 60 °C. The capacity retention after 500 cycles clearly shows that Al2O3-coated LTO outperforms the uncoated one, with a discharge capacity retention of ~98%. TEM and XPS analyses indicate that the surface reactions of Al2O3-coated LTO are suppressed, while uncoated LTO undergoes the (111) to (222) phase transformation, as previously reported in the literature.

Facile synthesis of CoWO4/RGO composites as superior anode materials for lithium-ion batteries

In this paper, a facile method has been developed to synthesize supported CoWO4 on the reduced graphene oxide (RGO) as high-performance anode material for Li-ion batteries. The composites with cuboid-like CoWO4 nanoparticles were prepared by directly adding graphene oxide into the precursor solution followed by a hydrothermal treatment. Different analytical methods like high-resolution TEM, XRD, TGA, and XPS characterizations were employed to illustrate structural information of the as-prepared CoWO4 and CoWO4/RGO composites. In addition, the Li-ion battery performance using the composites as anode materials was also discussed based on the detailed galvanostatic charge-discharge cycling tests. The result shows that the specific capacity of the as-prepared CoWO4/RGO composites can reach 533.3 mAh g−1 after 50 cycles at a current density of 100 mA g−1. During the whole cyclic process, the coulombic efficiency was maintained higher than 90%. Therefore, CoWO4, as an environment-friendly and cost-effective anode material, has promising potential for Li-ion batteries.

Chemical precipitation synthesis of KCoF3 for supercapacitor applications

A simple chemical precipitation method is applied to synthesize pure-phase KCoF3 with size in the range of 1–5 μm, which is further used as electrode material in supercapacitors. The cyclic voltammetry, electrochemical impedance spectroscopy measurements, and galvanostatic charge-discharge cycling test measurements are carried out for the KCoF3 electrode, and the results show a specific capacitance of 286 F⋅g−1 at 0.5 A⋅g−1 in 6.0 M KOH electrolyte. Particularly, KCoF3 electrode exhibits long cycling lifetime with 96% retention of initial capacitance after 1000 cycles at a current density of 5.0 A⋅g−1.

A performance comparison of protective silicate-coated lead and non-coated lead electrodes in various kind electrolytes of gel valve-regulated lead-acid battery

A novel silicate-based protective film was formed on negative electrodes and compared of the performance in various electrolyte systems of lead-acid batteries. The sodium silicate-based coating for the negative electrode component of a gel valve-regulated lead-acid (gel-VRLA) battery was applied for the first time in the literature. The battery system was produced by sodium silicate-coated negative electrodes and lead oxide positive electrodes in various kinds of electrolyte. Electrochemical characterization of cells and battery prototypes were done by cyclic voltammetric (CV) analysis, electrochemical impedance spectroscopic (EIS) analysis, and cyclic charge-discharge tests. The surface morphologies of silicate-coated electrodes were investigated by scanning electron microscopic analysis after cyclic voltammetric analysis and charge-discharge tests. The coating of silicate on the surface of negative electrodes increased the corrosion resistance of a VRLA battery according to the Tafel polarization curves. Indeed, sulfation on the negative electrode component of the battery have significantly reduced with silicate coatings of them. Besides, the prepared novel silicate-based protective film have increased the battery performance of a VRLA. Silicate-based coatings for electrodes can be used for industrial battery production for many different battery types due to their amazing anti-corrosion properties in acidic media.

Enabling high rate charge and discharge capability, low internal resistance, and excellent cycleability for Li-ion batteries utilizing graphene additives

A liquid-phase mixing method is adopted to uniformly disperse the graphene nanosheets onto LiNi1/3Co1/3Mn1/3O2 cathode for high-performance Li-ion batteries (LIBs). The electrochemical performance was characterized using a full pouch cells with state-of-the-art electrode areal loading (compared to half coin cells). The addition of graphene sheets (i.e., only 1 wt%) significantly improves the high rate capability for charging and discharging operation. For example, 6 times improvement in 5 C charging was achieved providing further insights in enabling extreme fast charging for LIBs. Other benefits include longer cycleability, lower internal resistance, and higher lithium ion diffusion coefficient, demonstrated by charge-discharge cycling tests and electrochemical impedance spectroscopy. Higher capacity retention of 88.2% and decreased internal resistance of ∼0.9 Ω are observed after 400 cycles. The diffusion coefficient of Li ions is 6.49 × 10−8 cm2 s−1 when charged to 4.2 V, which is approximately 1.37 times higher compared to the configuration with no graphene sheet (4.74 × 10−8 cm2 s−1). The improved performance is ascribed to a robust network among the active materials formed by graphene sheets, which serves as an extended current conductor and facilitates charge transfer, ionic reversibility, and ionic transportation.

XAFS Analysis of Voltage Depression Mechanism after Charge-Discharge Cycling Tests for Li-rich Cathode Materials

XAFS Analysis of Voltage Depression Mechanism after Charge-Discharge Cycling Tests for Li-rich Cathode Materials

The electrodeposition of manganese oxide on graphite electrode in-situ exfoliated for solid state rechargeable Zn-oxygen battery

The manganese oxide on in-situ exfoliated graphite has been fabricated by two-step process including anodic exfoliating and anodic depositing for solid state rechargeable Zn-oxygen battery, which exhibits high open circuit voltage and long cycle life. The morphology, phase composition, chemical composition and real surface area of the electrode in preparation process of manganese oxide on in-situ exfoliated graphite has been also characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and chronoamperometric. The charge-discharge cycling test has shown superior rechargeability for solid state Zn-oxygen battery. This work suggests that such a nanocomposite electrode offers promise for portable electronics.

Sonochemical synthesis of Co2SnO4 nanocubes for supercapacitor applications

In this work, a simple sonochemical route was followed to synthesize cobalt stannate (Co2SnO4) nanocubes using stannous and cobalt chlorides as the precursors in alkaline medium at room temperature. The structure, composition and surface morphology of synthesized Co2SnO4 nanocubes have been characterized by using X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR), Field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) indicates that the Co2SnO4 nanocubes are crystalline, single-phase without any impurity phase; the sizes of nanocubes are ∼100 nm. The cyclic voltammetry, galvanostatic charge-discharge cycling test, and electrochemical impedance spectroscopy (EIS) measurements are carried out for the Co2SnO4 nanocubes shows a specific capacitance 237 F g−1 at 0.5 mA cm−2 current density and in 1 M Na2SO4 electrolyte. Co2SnO4 nanocubes exhibit long cycling life with 80% retention of initial capacitance after 2000 cycles and the excellent rate capability at 15 mA cm−2 as much as 70% of that at 0.5 mA cm−2 suggest its potential use for supercapacitor applications.

A Low-Cost and High-Performance Sulfonated Polyimide Proton-Conductive Membrane for Vanadium Redox Flow/Static Batteries.

A novel side-chain-type fluorinated sulfonated polyimide (s-FSPI) membrane is synthesized for vanadium redox batteries (VRBs) by high-temperature polycondensation and grafting reactions. The s-FSPI membrane has a vanadium ion permeability that is over an order of magnitude lower and has a proton selectivity that is 6.8 times higher compared to those of the Nafion 115 membrane. The s-FSPI membrane possesses superior chemical stability compared to most of the linear sulfonated aromatic polymer membranes reported for VRBs. Also, the vanadium redox flow/static batteries (VRFB/VRSB) assembled with the s-FSPI membranes exhibit stable battery performance over 100- and 300-time charge-discharge cycling tests, respectively, with significantly higher battery efficiencies and lower self-discharge rates than those with the Nafion 115 membranes. The excellent physicochemical properties and VRB performance of the s-FSPI membrane could be attributed to the specifically designed molecular structure with the hydrophobic trifluoromethyl groups and flexible sulfoalkyl pendants being introduced on the main chains of the membrane. Moreover, the cost of the s-FSPI membrane is only one-fourth that of the commercial Nafion 115 membrane. This work opens up new possibilities for fabricating high-performance proton-conductive membranes at low costs for VRBs.

Performance of lithium-ion capacitors using pre-lithiated multiwalled carbon nanotubes/graphite composite as negative electrode

Multiwalled carbon nanotubes have been synthesized by floating reactant method in a vertical tubular reactor. An internal short approach process was developed to achieve the pre-lithiated multiwalled carbon nanotube MWCNTs/graphite composite anodes. Lithium-ion capacitors (LICs) were composed of a pre-lithiated multiwalled carbon nanotubes/graphite composite anode and an activated carbon (AC) cathode. The electrochemical performance of LICs with different MWCNTs content was investigated through galvanostatic charge/discharge and electrochemical impedance. The results show that the charge–discharge performance of LICs was greatly improved with the addition of MWCNTs in anodes. LIC25 (25 wt% MWCNTs) was found to achieve the optimal electrochemical performance. The LIC25 hold a specific capacitance of 58.2 F/g at the current density of 100 mA/g. The maximum energy density and power density were up to 96 Wh/kg and 10.1 kW/kg, respectively, in the current range of 100~8000 mA/g. The continuous galvanostatic charge–discharge cycling tests revealed that the LIC25 maintained excellent capacity retention of 86% after 3000 cycles.