Effect of PPy/PEG conducting polymer film on electrochemical performance of LiFePO4 cathode material for Li-ion batteries

2013 ◽  
Vol 67 (8) ◽  
Author(s):  
Renáta Oriňáková ◽  
Andrea Fedorková ◽  
Andrej Oriňák
Keyword(s):  
Electrochemical Performance ◽  
Conducting Polymer ◽  
Cathode Materials ◽  
Electronic Conductivity ◽  
Specific Capacity ◽  
Lithium Ion ◽  
Structural Defects ◽  
Portable Electronics ◽  
Lifepo4 Cathode ◽  
Conducting Polymer Films

AbstractRechargeable lithium-ion batteries (LIBs) have been the most commonly used batteries in the portable electronics market for many years. Polypyrrole (PPy) was now investigated as a conducting addition agent to enhance the cathode and anode materials performance in LIBs. Actual development in the synthesis and modification of the most promising cathode materials, LiFePO4, is described in this mini-review. The main aim of this mini-review is to highlight the effect of PPy based conducting polymer films on the electrochemical efficiency of LiFePO4 based cathode materials for LIBs summarizing our own research. Influence of the polyethylene glycol (PEG) additive in the PPy coating layer was evaluated. The improved electrochemical performance can be attributed to the enhanced electronic conductivity, higher solubility of ions originating from the electrolyte, higher movability of dissolved Li+ ions, and improved structural flexibility resulting from the incorporation of the PPy or PPy/PEG conducting polymer layer. The stabilizing effect of PEG in PPy was reflected in lowered cross-linking and reduced structural defects and, in consequence, in higher specific capacity of PPy/PEG-LiFePO4 cathodes compared to that of PPy-LiFePO4 cathodes and bare LiFePO4 cathodes.

scholarly journals Boosting the Rate and Cycling Performance of β-LixV2O5 Nanorods for Li Ion Battery by Electrode Surface Decoration

2019 ◽  
Author(s):  
Panpan Wang ◽  
Yue Du ◽  
Baoyou Zhang ◽  
Yanxin Yao ◽  
Yuchen Xiao ◽  
...  
Keyword(s):  
Electrochemical Performance ◽  
Current Density ◽  
Electrochemical Impedance ◽  
Electronic Conductivity ◽  
Specific Capacity ◽  
Rate Capability ◽  
Lithium Ion ◽  
Ex Situ ◽  
Practical Application ◽  
Surface Decoration

The <i>β-</i>phase lithium vanadium oxide bronze (<i>β-</i>Li<i><sub>x</sub></i>V<sub>2</sub>O<sub>5</sub>) with high theoretic specific capacity up to 440 mAh g<sup>-1</sup> is considered as promising cathode materials, however, their practical application is hindered by its poor ionic and electronic conductivity, resulting in unsatisfied cyclic stability and rate capability. Herein, we report the surface decoration of <i>β-</i>Li<i><sub>x</sub></i>V<sub>2</sub>O<sub>5</sub> cathode using both reduced oxide graphene and ionic conductor LaPO<sub>4</sub>, which significantly promotes the electronic transfer and Li<sup>+</sup> diffusion rate, respectively. As a result, the rGO/LaPO<sub>4</sub>/Li<i><sub>x</sub></i>V<sub>2</sub>O<sub>5</sub> composite exhibits excellent electrochemical performance in terms of high reversible specific capacity of 275.7 mAh g<sup>-1</sup> with high capacity retention of 84.1% after 100 cycles at a current density of 60 mA g<sup>-1</sup>, and acceptable specific capacity of 170.3 mAh g<sup>-1</sup> at high current density of 400 mA g<sup>-1</sup>. The cycled electrode is also analyzed by electrochemical impedance spectroscopy, <i>ex-situ </i>X-ray diffraction and scanning electron microscope, providing further insights into the improvement of electrochemical performance. Our results provide an effective approach to boost the electrochemical properties of lithium vanadates for practical application in lithium ion batteries.

scholarly journals Electrochemically Inert Li2MnO3: The Key to Improving the Cycling Stability of Li-Rich Manganese Oxide Used in Lithium-Ion Batteries

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4751
Author(s):  
Lian-Bang Wang ◽  
He-Shan Hu ◽  
Wei Lin ◽  
Qing-Hong Xu ◽  
Jia-Dong Gong ◽  
...  
Keyword(s):  
Electrochemical Performance ◽  
Cathode Material ◽  
Manganese Oxide ◽  
Lithium Ion Batteries ◽  
Retention Rate ◽  
Specific Capacity ◽  
Lithium Ion ◽  
Cycling Stability ◽  
Structural Defects ◽  
Hydrothermal Route

Lithium-rich manganese oxide is a promising candidate for the next-generation cathode material of lithium-ion batteries because of its low cost and high specific capacity. Herein, a series of xLi2MnO3·(1 − x)LiMnO2 nanocomposites were designed via an ingenious one-step dynamic hydrothermal route. A high concentration of alkaline solution, intense hydrothermal conditions, and stirring were used to obtain nanoparticles with a large surface area and uniform dispersity. The experimental results demonstrate that 0.072Li2MnO3·0.928LiMnO2 nanoparticles exhibit a desirable electrochemical performance and deliver a high capacity of 196.4 mAh g−1 at 0.1 C. This capacity was maintained at 190.5 mAh g−1 with a retention rate of 97.0% by the 50th cycle, which demonstrates the excellent cycling stability. Furthermore, XRD characterization of the cycled electrode indicates that the Li2MnO3 phase of the composite is inert, even under a high potential (4.8 V), which is in contrast with most previous reports of lithium-rich materials. The inertness of Li2MnO3 is attributed to its high crystallinity and few structural defects, which make it difficult to activate. Hence, the final products demonstrate a favorable electrochemical performance with appropriate proportions of two phases in the composite, as high contents of inert Li2MnO3 lower the capacity, while a sufficient structural stability cannot be achieved with low contents. The findings indicate that controlling the composition through a dynamic hydrothermal route is an effective strategy for developing a Mn-based cathode material for lithium-ion batteries.

An enhancement of electrochemical performance in lithium-ion battery via tantalum oxide coated nickel-rich cathode materials

2021 ◽  
Author(s):  
Fengling Chen ◽  
Jiannan Lin ◽  
Yifan Chen ◽  
Binbin Dong ◽  
Chujun Yin ◽  
...  
Keyword(s):  
Electrochemical Performance ◽  
Cathode Materials ◽  
Large Scale ◽  
Specific Capacity ◽  
Tantalum Oxide ◽  
Rate Capability ◽  
Lithium Ion ◽  
Side Reactions ◽  
Functional Layer ◽  
Voltage Range

Abstract Nickel-rich cathode materials are increasingly being applied in commercial lithium-ion batteries to realize higher specific capacity as well as improve energy density. However, low structural stability and rapid capacity decay at high voltage and temperature hinder their rapid large-scale application. Herein, a wet chemical method followed by a post-annealing process is utilized to realize the surface coating of tantalum oxide on LiNi0.88Mn0.03Co0.09O2, and the electrochemical performance is improved. The modified LiNi0.88Mn0.03Co0.09O2 displays an initial discharge capacity of ~233 mAh/g at 0.1 C and 174 mAh/g at 1 C after 150 cycles in the voltage range of 3.0-4.4 V at 45 ℃, and it also exhibits an enhanced rate capability with 118 mAh/g at 5 C. The excellent performance is due to the introduction of tantalum oxide as a stable and functional layer to protect the surface of LiNi0.88Mn0.03Co0.09O2, and the surface side reactions and cation mixing are suppressed at the same time without hampering the charge transfer kinetics.

Microstructure and electrochemical performance of LiFePO4 cathode materials modified with binuclear metal aminophthalocyanines

2018 ◽  
Vol 22 (12) ◽  
pp. 1072-1081 ◽  
Author(s):  
Yuanyuan Su ◽  
Feifei Xu ◽  
Ruiqiong Wang ◽  
Ronglan Zhang ◽  
Jianshe Zhao
Keyword(s):  
Electrochemical Performance ◽  
Lithium Ion Batteries ◽  
Electrode Materials ◽  
Preparation Method ◽  
Solvothermal Method ◽  
Specific Capacity ◽  
Lithium Ion ◽  
Initial Discharge ◽  
Lifepo4 Cathode ◽  
Binuclear Metal

The monodispersed LiFe[Formula: see text]M[Formula: see text]PO4/C [[Formula: see text] [Formula: see text] 0.0040; [Formula: see text] = Mn[Formula: see text], Co[Formula: see text], Ni[Formula: see text], Cu[Formula: see text], Zn[Formula: see text]] nanocomposites obtained by LiFePO4 modified with binuclear metal aminophthalocyanines (M2(PcTa)2O and M2(PcTa)2C(CF[Formula: see text] are utilized as positive electrode materials for lithium ion batteries. The preparation method for these nanocomposites is a controllable solvothermal method using a mixture of ethylene glycol and [Formula: see text],[Formula: see text]-dimethylformamide as the solvent. The microstructure and electrochemical properties of the different nanocomposites are discussed and compared. The results show that the LiFePO4 samples modified with M2(PcTa)2C(CF[Formula: see text]can improve the initial discharge specific capacity of the lithium ion battery up to 154.2 mAh.g[Formula: see text]at the rate of 0.1 C, and 93.5% of the initial discharge capacity could be retained after 50 cycles. This research shows that the proposed process can enhance the electrochemical performance of high power LiFePO4 for lithium ion batteries.

Preparation and Electrochemical Performance of Li3V2(PO4)3 Cathode Materials by Microwave-Heated Sol-Gel Method

2010 ◽  
Vol 156-157 ◽  
pp. 1219-1222 ◽  
Author(s):  
Bo Quan Jiang ◽  
Shu Fen Hu ◽  
Min Wei Wang
Keyword(s):  
Electrochemical Performance ◽  
Cathode Materials ◽  
Electrochemical Impedance ◽  
Sol Gel ◽  
Specific Capacity ◽  
Lithium Ion ◽  
Lithium Vanadium Phosphate ◽  
Optimal Conditions ◽  
Gel Method ◽  
Sol Gel Method

The lithium vanadium phosphate (Li3V2(PO4)3 solid cathode materials were synthesized by microwave-heated sol-gel method using lithium hydroxide, ammonium metavanadate, phosphate and citric acid as starting materials. The test was conducted with orthogonal experiment method. The optimal conditions for (Li3V2(PO4)3 synthesis were determined to be microwave heating time of 10 min, microwave power of 700 W, Li/V molar ratio of 3.05:2.0 and pH value(gel solution) of 7.0. The synthesized (Li3V2(PO4)3 under the optimal conditions demonstrated perfect crystal growth and good electrochemical performance with initial charge/discharge specific capacity of 172.42 mAh·g-1/154.93 mAh·g-1 and discharge decay rate of 2.25 % after 50 cycles. The lithium ion diffusion coefficient was determined to be 1.434 ×10-8 cm2·s-1 by electrochemical impedance spectroscopy and mathematical models derived from simulative equivalent circuit.

scholarly journals Polyethylene Oxide as a Multifunctional Binder for High-Performance Ternary Layered Cathodes

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3992
Author(s):  
Jinshan Mo ◽  
Dongmei Zhang ◽  
Mingzhe Sun ◽  
Lehao Liu ◽  
Weihao Hu ◽  
...  
Keyword(s):  
Polyethylene Oxide ◽  
Cathode Materials ◽  
High Performance ◽  
Electrochemical Impedance ◽  
Electronic Conductivity ◽  
Specific Capacity ◽  
Lithium Ion ◽  
Cycle Performance ◽  
Rate Performance ◽  
High Electronic Conductivity

Nickel cobalt manganese ternary cathode materials are some of the most promising cathode materials in lithium-ion batteries, due to their high specific capacity, low cost, etc. However, they do have a few disadvantages, such as an unstable cycle performance and a poor rate performance. In this work, polyethylene oxide (PEO) with high ionic conductance and flexibility was utilized as a multifunctional binder to improve the electrochemical performance of LiNi0.6Co0.2Mn0.2O2 cathode materials. Scanning electron microscopy showed that the addition of PEO can greatly improve the adhesion of the electrode components and simultaneously enhance the integrity of the electrode. Thus, the PEO-based electrode (20 wt% PEO in PEO/PVDF) shows a high electronic conductivity of 19.8 S/cm, which is around 15,000 times that of the pristine PVDF-based electrode. Moreover, the PEO-based electrode exhibits better cycling stability and rate performance, i.e., the capacity increases from 131.1 mAh/g to 147.3 mAh/g at 2 C with 20 wt% PEO addition. Electrochemical impedance measurements further indicate that the addition of the PEO binder can reduce the electrode resistance and protect the LiNi0.6Co0.2Mn0.2O2 cathode materials from the liquid electrolyte attack. This work offers a simple yet effective method to improve the cycling performance of the ternary cathode materials by adding an appropriate amount of PEO as a binder in the electrode fabrication process.

Boosting the Rate and Cycling Performance of β-LixV2O5 Nanorods for Li Ion Battery by Electrode Surface Decoration

2019 ◽  
Author(s):  
Panpan Wang ◽  
Yue Du ◽  
Baoyou Zhang ◽  
Yanxin Yao ◽  
Yuchen Xiao ◽  
...  
Keyword(s):  
Electrochemical Performance ◽  
Current Density ◽  
Electrochemical Impedance ◽  
Electronic Conductivity ◽  
Specific Capacity ◽  
Rate Capability ◽  
Lithium Ion ◽  
Ex Situ ◽  
Practical Application ◽  
Surface Decoration

The <i>β-</i>phase lithium vanadium oxide bronze (<i>β-</i>Li<i><sub>x</sub></i>V<sub>2</sub>O<sub>5</sub>) with high theoretic specific capacity up to 440 mAh g<sup>-1</sup> is considered as promising cathode materials, however, their practical application is hindered by its poor ionic and electronic conductivity, resulting in unsatisfied cyclic stability and rate capability. Herein, we report the surface decoration of <i>β-</i>Li<i><sub>x</sub></i>V<sub>2</sub>O<sub>5</sub> cathode using both reduced oxide graphene and ionic conductor LaPO<sub>4</sub>, which significantly promotes the electronic transfer and Li<sup>+</sup> diffusion rate, respectively. As a result, the rGO/LaPO<sub>4</sub>/Li<i><sub>x</sub></i>V<sub>2</sub>O<sub>5</sub> composite exhibits excellent electrochemical performance in terms of high reversible specific capacity of 275.7 mAh g<sup>-1</sup> with high capacity retention of 84.1% after 100 cycles at a current density of 60 mA g<sup>-1</sup>, and acceptable specific capacity of 170.3 mAh g<sup>-1</sup> at high current density of 400 mA g<sup>-1</sup>. The cycled electrode is also analyzed by electrochemical impedance spectroscopy, <i>ex-situ </i>X-ray diffraction and scanning electron microscope, providing further insights into the improvement of electrochemical performance. Our results provide an effective approach to boost the electrochemical properties of lithium vanadates for practical application in lithium ion batteries.

scholarly journals Nonstoichiometric Cu0.6Ni0.4Co2O4 Nanowires as an Anode Material for High Performance Lithium Storage

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 191
Author(s):  
Junhao Li ◽  
Ningyi Jiang ◽  
Jinyun Liao ◽  
Yufa Feng ◽  
Quanbing Liu ◽  
...  
Keyword(s):  
Transition Metal ◽  
Electrochemical Performance ◽  
Metal Oxides ◽  
Lithium Ion Batteries ◽  
Transition Metal Oxides ◽  
Anode Materials ◽  
High Performance ◽  
Electronic Conductivity ◽  
Specific Capacity ◽  
Lithium Ion

Transition metal oxide is one of the most promising anode materials for lithium-ion batteries. Generally, the electrochemical property of transition metal oxides can be improved by optimizing their element components and controlling their nano-architecture. Herein, we designed nonstoichiometric Cu0.6Ni0.4Co2O4 nanowires for high performance lithium-ion storage. It is found that the specific capacity of Cu0.6Ni0.4Co2O4 nanowires remain 880 mAh g−1 after 50 cycles, exhibiting much better electrochemical performance than CuCo2O4 and NiCo2O4. After experiencing a large current charge and discharge state, the discharge capacity of Cu0.6Ni0.4Co2O4 nanowires recovers to 780 mAh g−1 at 50 mA g−1, which is ca. 88% of the initial capacity. The high electrochemical performance of Cu0.6Ni0.4Co2O4 nanowires is related to their better electronic conductivity and synergistic effect of metals. This work may provide a new strategy for the design of multicomponent transition metal oxides as anode materials for lithium-ion batteries.

scholarly journals PEDOT-Coated Red Phosphorus Nanosphere Anodes for Pseudocapacitive Potassium-Ion Storage

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1732
Author(s):  
Dan Zhao ◽  
Qian Zhao ◽  
Zhenyu Wang ◽  
Lan Feng ◽  
Jinying Zhang ◽  
...  
Keyword(s):  
Surface Engineering ◽  
Electronic Conductivity ◽  
Specific Capacity ◽  
Lithium Ion ◽  
Average Diameter ◽  
Potassium Ion ◽  
Red Phosphorus ◽  
Fast Charging ◽  
Potential Alternative ◽  
High Theoretical Capacity

Potassium-ion batteries (KIBs) have come up as a potential alternative to lithium-ion batteries due to abundant potassium storage in the crust. Red phosphorus is a promising anode material for KIBs with abundant resources and high theoretical capacity. Nevertheless, large volume expansion, low electronic conductivity, and limited K+ charging speed in red phosphorus upon cycling have severely hindered the development of red phosphorus-based anodes. To obtain improved conductivity and structural stability, surface engineering of red phosphorus is required. Poly(3,4-ethylenedioxythiophene) (PEDOT)-coated red phosphorus nanospheres (RPNP@PEDOT) with an average diameter of 60 nm were synthesized via a facile solution-phase approach. PEDOT can relieve the volume change of red phosphorus and promote electron/ion transportation during charge−discharge cycles, which is partially corroborated by our DFT calculations. A specific capacity of 402 mAh g−1 at 0.1 A g−1 after 40 cycles, and a specific capacity of 302 mAh g−1 at 0.5 A g−1 after 275 cycles, were achieved by RPNP@PEDOT anode with a high pseudocapacitive contribution of 62%. The surface–interface engineering for the organic–inorganic composite of RPNP@PEDOT provides a novel perspective for broad applications of red phosphorus-based KIBs in fast charging occasions.

Sign in / Sign up

Export Citation Format

Share Document