scholarly journals Operando Calorimetry Informs the Origin of Rapid Rate Performance in Microwave-Prepared TiNb2O7 Electrodes

2020 ◽  
Author(s):  
Sun Woong Baek ◽  
Kira E. Wyckoff ◽  
Danielle M. Butts ◽  
Jadon Bienz ◽  
AMPOL LIKITCHATCHAWANKUN ◽  
...  
Keyword(s):  
Synthesis Method ◽  
Lithium Ion ◽  
Enthalpy Of Mixing ◽  
High Rate ◽  
Rapid Rate ◽  
Rate Performance ◽  
Ion Diffusion ◽  
Phase Compound ◽  
Graphite Anodes ◽  
Lithium Ion Diffusion

<div>The shear-phase compound TiNb<sub>2</sub>O<sub>7</sub> has recently emerged as a safe and high-volumetric density replacement for graphite anodes in lithium ion batteries. An appealing feature of TiNb<sub>2</sub>O<sub>7</sub> is that it retains capacity even at high cycling rates. Here we demonstrate that phase pure and crystalline TiNb<sub>2</sub>O<sub>7</sub> can be rapidly prepared using a high-temperature microwave synthesis method. Studies of the charging and discharging of this material, including through operando calorimetry, permit key thermodynamic parameters to be revealed. The nature of heat generation is dominated by Joule heating, which sensitively changes as the conductivity of the electrode increases with increasing lithiation. The enthalpy of mixing, obtained from operando calorimetry, is found to be small across the different degrees of lithiation pointing to the high rate of lithium ion diffusion at the origin of rapid rate performance.</div>

scholarly journals Operando Calorimetry Informs the Origin of Rapid Rate Performance in Microwave-Prepared TiNb2O7 Electrodes

2020 ◽  
Author(s):  
Sun Woong Baek ◽  
Kira E. Wyckoff ◽  
Danielle M. Butts ◽  
Jadon Bienz ◽  
AMPOL LIKITCHATCHAWANKUN ◽  
...  
Keyword(s):  
Synthesis Method ◽  
Lithium Ion ◽  
Enthalpy Of Mixing ◽  
High Rate ◽  
Rapid Rate ◽  
Rate Performance ◽  
Ion Diffusion ◽  
Phase Compound ◽  
Graphite Anodes ◽  
Lithium Ion Diffusion

<div>The shear-phase compound TiNb<sub>2</sub>O<sub>7</sub> has recently emerged as a safe and high-volumetric density replacement for graphite anodes in lithium ion batteries. An appealing feature of TiNb<sub>2</sub>O<sub>7</sub> is that it retains capacity even at high cycling rates. Here we demonstrate that phase pure and crystalline TiNb<sub>2</sub>O<sub>7</sub> can be rapidly prepared using a high-temperature microwave synthesis method. Studies of the charging and discharging of this material, including through operando calorimetry, permit key thermodynamic parameters to be revealed. The nature of heat generation is dominated by Joule heating, which sensitively changes as the conductivity of the electrode increases with increasing lithiation. The enthalpy of mixing, obtained from operando calorimetry, is found to be small across the different degrees of lithiation pointing to the high rate of lithium ion diffusion at the origin of rapid rate performance.</div>

scholarly journals Improved conductivity and ionic mobility in nanostructured thin films via aliovalent doping for ultra-high rate energy storage

2020 ◽  
Vol 2 (5) ◽  
pp. 2160-2169
Author(s):  
Clayton T. Kacica ◽  
Pratim Biswas
Keyword(s):  
Thin Films ◽  
Energy Storage ◽  
Lithium Ion Battery ◽  
Lithium Ion ◽  
Ionic Mobility ◽  
High Rate ◽  
Ion Diffusion ◽  
Nanostructured Thin Films ◽  
Lithium Ion Diffusion ◽  
Aliovalent Doping

Synthesis of Cu-doped TiO2 nanostructures with excellent high-rate lithium-ion battery performance and enhanced lithium-ion diffusion.

scholarly journals Investigation of Lithium Ion Diffusion of Graphite Anode by the Galvanostatic Intermittent Titration Technique

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4683 ◽  
Author(s):  
Jong Hyun Park ◽  
Hana Yoon ◽  
Younghyun Cho ◽  
Chung-Yul Yoo
Keyword(s):  
Diffusion Coefficient ◽  
Lithium Ion ◽  
Open Circuit ◽  
Quasi Equilibrium ◽  
Ion Diffusion ◽  
Galvanostatic Intermittent Titration Technique ◽  
Graphite Anodes ◽  
Ion Intercalation ◽  
Lithium Ion Diffusion ◽  
Titration Technique

Graphite is used as a state-of-the-art anode in commercial lithium-ion batteries (LIBs) due to its highly reversible lithium-ion storage capability and low electrode potential. However, graphite anodes exhibit sluggish diffusion kinetics for lithium-ion intercalation/deintercalation, thus limiting the rate capability of commercial LIBs. In order to determine the lithium-ion diffusion coefficient of commercial graphite anodes, we employed a galvanostatic intermittent titration technique (GITT) to quantify the quasi-equilibrium open circuit potential and diffusion coefficient as a function of lithium-ion concentration and potential for a commercial graphite electrode. Three plateaus are observed in the quasi-equilibrium open circuit potential curves, which are indicative of a mixed phase upon lithium-ion intercalation/deintercalation. The obtained diffusion coefficients tend to increase with increasing lithium concentration and exhibit an insignificant difference between charge and discharge conditions. This study reveals that the diffusion coefficient of graphite obtained with the GITT (1 × 10−11 cm2/s to 4 × 10−10 cm2/s) is in reasonable agreement with literature values obtained from electrochemical impedance spectroscopy. The GITT is comparatively simple and direct and therefore enables systematic measurements of ion intercalation/deintercalation diffusion coefficients for secondary ion battery materials.

EASY SYNTHESIS OF Li4Ti5O12/C MICROSPHERES CONTAINING NANOPARTICLES AS ANODE MATERIAL FOR HIGH-RATE Li-ION BATTERIES

2014 ◽  
Vol 21 (02) ◽  
pp. 1450023 ◽  
Author(s):  
XIAODONG ZHENG ◽  
LINA DONG ◽  
CHENCHU DONG
Keyword(s):  
Anode Material ◽  
Specific Capacity ◽  
Lithium Ion ◽  
High Rate ◽  
Conductive Network ◽  
Ion Diffusion ◽  
X Ray Diffraction ◽  
Compact Structure ◽  
Li Ion ◽  
Lithium Ion Diffusion

A microspherical Li 4 Ti 5 O 12/ C composite composed of interconnected nanoparticles with BP-2000 carbon black as carbon source is synthesized for use as an anode material in high-power lithium-ion batteries. The composite is prepared through precursor pretreatment including pre-sintering, ball-milling, and spray-drying. The structure, size and surface morphology of the as-prepared particles are investigated by X-ray diffraction and scanning electron microscopy. Results show that the obtained material has a microspherical morphology consisting of nanosized prime particles with compact structure. The precursor pretreatment effectively reduced the agglomeration of the prime particles caused by high temperature sintering and led to a more uniform distribution of BP-2000 on the surface of prime particles generating highly efficient conductive network. The specific capacity of the electrode at 20 C rate is 131 mAh g-1 and the loss of capacity is less than 2% after the 60 variation cycles (from 1 C to 20 C and back to 1 C). This excellent performance is attributed to the effective conductive network between the prime particles and the reduction of the lithium-ion diffusion pathway.

scholarly journals Polyimide-Derived Carbon-Coated Li4Ti5O12 as High-Rate Anode Materials for Lithium Ion Batteries

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1672
Author(s):  
Shih-Chieh Hsu ◽  
Tzu-Ten Huang ◽  
Yen-Ju Wu ◽  
Cheng-Zhang Lu ◽  
Huei Chu Weng ◽  
...  
Keyword(s):  
Carbon Source ◽  
Electrochemical Performance ◽  
Anode Materials ◽  
Lithium Ion ◽  
High Rate ◽  
Rate Performance ◽  
Molecular Arrangement ◽  
Thermal Imidization ◽  
Carbon Coated ◽  
Graphite Structure

Carbon-coated Li4Ti5O12 (LTO) has been prepared using polyimide (PI) as a carbon source via the thermal imidization of polyamic acid (PAA) followed by a carbonization process. In this study, the PI with different structures based on pyromellitic dianhydride (PMDA), 4,4′-oxydianiline (ODA), and p-phenylenediamine (p-PDA) moieties have been synthesized. The effect of the PI structure on the electrochemical performance of the carbon-coated LTO has been investigated. The results indicate that the molecular arrangement of PI can be improved when the rigid p-PDA units are introduced into the PI backbone. The carbons derived from the p-PDA-based PI show a more regular graphite structure with fewer defects and higher conductivity. As a result, the carbon-coated LTO exhibits a better rate performance with a discharge capacity of 137.5 mAh/g at 20 C, which is almost 1.5 times larger than that of bare LTO (94.4 mAh/g).

Sign in / Sign up

Export Citation Format

Share Document