scholarly journals Porous Polymer Gel Electrolytes Influence Lithium Transference Number and Cycling in Lithium-Ion Batteries

2021 ◽  
Vol 2 (2) ◽  
pp. 154-173
Author(s):  
Buket Boz ◽  
Hunter O. Ford ◽  
Alberto Salvadori ◽  
Jennifer L. Schaefer
Keyword(s):  
Transport Properties ◽  
Lithium Ion Batteries ◽  
Polymer Electrolyte ◽  
Active Material ◽  
Polymer Network ◽  
Rate Capability ◽  
Lithium Ion ◽  
Transference Number ◽  
Porous Polymer ◽  
Performance Property

To improve the energy density of lithium-ion batteries, the development of advanced electrolytes with enhanced transport properties is highly important. Here, we show that by confining the conventional electrolyte (1 M LiPF6 in EC-DEC) in a microporous polymer network, the cation transference number increases to 0.79 while maintaining an ionic conductivity on the order of 10−3 S cm−1. By comparison, a non-porous, condensed polymer electrolyte of the same chemistry has a lower transference number and conductivity, of 0.65 and 7.6 × 10−4 S cm−1, respectively. Within Li-metal/LiFePO4 cells, the improved transport properties of the porous polymer electrolyte enable substantial performance enhancements compared to a commercial separator in terms of rate capability, capacity retention, active material utilization, and efficiency. These results highlight the importance of polymer electrolyte structure–performance property relationships and help guide the future engineering of better materials.

Design Considerations to Improve Transport in Porous Electrodes for Lithium-Ion Batteries

2012 ◽  
Vol 1440 ◽  
Author(s):  
Rajeswari Chandrasekaran ◽  
Andrew Drews ◽  
Apoorv Shaligram ◽  
Jeffrey Sakamoto
Keyword(s):  
Transport Properties ◽  
Lithium Ion Batteries ◽  
Active Material ◽  
Rate Capability ◽  
Lithium Ion ◽  
Porous Electrodes ◽  
Design Considerations ◽  
Lithium Ion Cells ◽  
Effective Transport ◽  
The Relationship

ABSTRACTThe relationship between tortuosity and porosity and its influence on effective transport properties in lithium-ion cells was analyzed. The variation in cell performance with changes in component thicknesses, porosities and tortuosities was investigated. Optimal, novel electrode designs are developed to improve their rate capability even at higher active material loadings.

scholarly journals Utilizing the Intrinsic Thermal Instability of Swedenborgite Structured YBaCo4O7+δ as an Opportunity for Material Engineering in Lithium-Ion Batteries by Er and Ga Co-Doping Processes

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4565
Author(s):  
Sanghyuk Park ◽  
Kwangho Park ◽  
Ji-Seop Shin ◽  
Gyeongbin Ko ◽  
Wooseok Kim ◽  
...  
Keyword(s):  
Lithium Ion Batteries ◽  
Phase Stability ◽  
Electrochemical Impedance ◽  
Coulombic Efficiency ◽  
Structural Phase ◽  
Active Material ◽  
Rate Capability ◽  
Lithium Ion ◽  
Ion Migration ◽  
Co Doping

We firstly introduce Er and Ga co-doped swedenborgite-structured YBaCo4O7+δ (YBC) as a cathode-active material in lithium-ion batteries (LIBs), aiming at converting the phase instability of YBC at high temperatures into a strategic way of enhancing the structural stability of layered cathode-active materials. Our recent publication reported that Y0.8Er0.2BaCo3.2Ga0.8O7+δ (YEBCG) showed excellent phase stability compared to YBC in a fuel cell operating condition. By contrast, the feasibility of the LiCoO2 (LCO) phase, which is derived from swedenborgite-structured YBC-based materials, as a LIB cathode-active material is investigated and the effects of co-doping with the Er and Ga ions on the structural and electrochemical properties of Li-intercalated YBC are systemically studied. The intrinsic swedenborgite structure of YBC-based materials with tetrahedrally coordinated Co2+/Co3+ are partially transformed into octahedrally coordinated Co3+, resulting in the formation of an LCO layered structure with a space group of R-3m that can work as a Li-ion migration path. Li-intercalated YEBCG (Li[YEBCG]) shows effective suppression of structural phase transition during cycling, leading to the enhancement of LIB performance in Coulombic efficiency, capacity retention, and rate capability. The galvanostatic intermittent titration technique, cyclic voltammetry and electrochemical impedance spectroscopy are performed to elucidate the enhanced phase stability of Li[YEBCG].

PVDF-HFP-based porous polymer electrolyte membranes for lithium-ion batteries

2008 ◽  
Vol 184 (2) ◽  
pp. 420-426 ◽  
Author(s):  
Ruiying Miao ◽  
Bowen Liu ◽  
Zhongzheng Zhu ◽  
Yun Liu ◽  
Jianling Li ◽  
...  
Keyword(s):  
Lithium Ion Batteries ◽  
Polymer Electrolyte ◽  
Lithium Ion ◽  
Polymer Electrolyte Membranes ◽  
Porous Polymer ◽  
Electrolyte Membranes

scholarly journals Characterization and Laser Structuring of Aqueous Processed Li(Ni0.6Mn0.2Co0.2)O2 Thick-Film Cathodes for Lithium-Ion Batteries

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1840
Author(s):  
Penghui Zhu ◽  
Jiahao Han ◽  
Wilhelm Pfleging
Keyword(s):  
Acetic Acid ◽  
Lithium Ion Batteries ◽  
Thick Film ◽  
Active Material ◽  
Rate Capability ◽  
Lithium Ion ◽  
Ph Values ◽  
Laser Structuring ◽  
Methyl Pyrrolidone ◽  
High Processing

Lithium-ion batteries have led the revolution in portable electronic devices and electrical vehicles due to their high gravimetric energy density. In particular, layered cathode material Li(Ni0.6Mn0.2Co0.2)O2 (NMC 622) can deliver high specific capacities of about 180 mAh/g. However, traditional cathode manufacturing involves high processing costs and environmental issues due to the use of organic binder polyvinylidenfluoride (PVDF) and highly toxic solvent N-methyl-pyrrolidone (NMP). In order to overcome these drawbacks, aqueous processing of thick-film NMC 622 cathodes was studied using carboxymethyl cellulose and fluorine acrylic hybrid latex as binders. Acetic acid was added during the mixing process to obtain slurries with pH values varying from 7.4 to 12.1. The electrode films could be produced with high homogeneity using slurries with pH values smaller than 10. Cyclic voltammetry measurements showed that the addition of acetic acid did not affect the redox reaction of active material during charging and discharging. Rate capability tests revealed that the specific capacities with higher slurry pH values were increased at C-rates above C/5. Cells with laser structured thick-film electrodes showed an increase in capacity by 40 mAh/g in comparison to cells with unstructured electrodes.

MoS2 Layers Decorated RGO Composite Prepared by a One-Step High-Temperature Solvothermal Method as Anode for Lithium-Ion Batteries

NANO ◽  
2018 ◽  
Vol 13 (11) ◽  
pp. 1850135 ◽  
Author(s):  
Xuehua Liu ◽  
Bingning Wang ◽  
Jine Liu ◽  
Zhen Kong ◽  
Binghui Xu ◽  
...  
Keyword(s):  
High Temperature ◽  
Lithium Ion Batteries ◽  
Active Material ◽  
Rate Capability ◽  
Lithium Ion ◽  
Cost Effective ◽  
Reversible Capacity ◽  
Reduced Graphene ◽  
One Step ◽  
Anode Active Material

A one-step high-temperature solvothermal approach to the synthesis of monolayer or bilayer MoS2 anchored onto reduced graphene oxide (RGO) sheet (denoted as MoS2/RGO) is described. It was found that single-layered or double-layered MoS2 were synthesized directly without an extra exfoliation step and well dispersed on the surface of crumpled RGO sheets with random orientation. The prepared MoS2/RGO composites delivered a high reversible capacity of 900[Formula: see text]mAhg[Formula: see text] after 200 cycles at a current density of 200[Formula: see text]mAg[Formula: see text] as well as good rate capability as anode active material for lithium ion batteries. This one-step high-temperature hydrothermal strategy provides a simple, cost-effective and eco-friendly way to the fabrication of exfoliated MoS2 layers deposited onto RGO sheets.

The network gel polymer electrolyte based on poly(acrylate-co-imide) and its transport properties in lithium ion batteries

2008 ◽  
Vol 13 (9) ◽  
pp. 1425-1431 ◽  
Author(s):  
Fu-Ming Wang ◽  
Jyh-Tsung Lee ◽  
Ju-Hsiang Cheng ◽  
Chin-Shu Cheng ◽  
Chang-Rung Yang
Keyword(s):  
Transport Properties ◽  
Lithium Ion Batteries ◽  
Polymer Electrolyte ◽  
Gel Polymer Electrolyte ◽  
Lithium Ion

scholarly journals A Three-Dimensional Electrospun Li6.4La3Zr1.4Ta0.6O12–Poly (Vinylidene Fluoride-Hexafluoropropylene) Gel Polymer Electrolyte for Rechargeable Solid-State Lithium Ion Batteries

2021 ◽  
Vol 9 ◽  
Author(s):  
Donghuang Wang ◽  
Dan Cai ◽  
Yu Zhong ◽  
Zhao Jiang ◽  
Shengzhao Zhang ◽  
...  
Keyword(s):  
Solid State ◽  
Lithium Ion Batteries ◽  
Polymer Electrolyte ◽  
Vinylidene Fluoride ◽  
Gel Polymer Electrolyte ◽  
Three Dimensional ◽  
Lithium Ion ◽  
Porous Polymer ◽  
Electrospinning Technique ◽  
Electrolyte Uptake

Developing high-quality solid-state electrolytes is important for producing next-generation safe and stable solid-state lithium-ion batteries. Herein, a three-dimensional highly porous polymer electrolyte based on poly (vinylidenefluoride-hexafluoropropylene) (PVDF-HFP) with Li6.4La3Zr1.4Ta0.6O12 (LLZTO) nanoparticle fillers (PVDF-HFP-LLZTO) is prepared using the electrospinning technique. The PVDF-HFP-LLZTO gel polymer electrolyte possesses a high ionic conductivity of 9.44 × 10–4 S cm−1 and a Li-ion transference number of 0.66, which can be ascribed that the 3D hierarchical nanostructure with abundant porosity promotes the liquid electrolyte uptake and wetting, and LLZTO nanoparticles fillers decrease the crystallinity of PVDF-HFP. Thus, the solid-state lithium battery with LiFePO4 cathode, PVDF-HFP-LLZTO electrolyte, and Li metal anode exhibits enhanced electrochemical performance with improved cycling stability.

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