Electrochemical Characterization of LiTi₂(PO₄)₃as Anode Material for Aqueous Rechargeable Lithium Batteries

Abstract

RAPET (Reactions under Autogenic Pressure at Elevated Temperature) method has been used to synthesize lithium titanium phosphate anode material. The prepared compound is characterized by X-ray diffraction analysis. The electrochemical behavior has been studied in different aqueous electrolytes using cyclic voltammetry (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS) techniques. CV peak current is proportional to the square root of scan rate. The system satisfies the required conditions for a reversible redox system. LiTi 2 (PO 4 ) 3 is found to undergo lithium insertion at all concentrations of LiNO 3 electrolyte. The values of -Z when all the points of the impedance spectra measured in 2 M Li 2 SO 4 electrolyte compared at 5 mHz are found to show a minimum at the potential close to the CV peak potential during charge and discharge. The cell, LiTi 2 (PO 4 ) 3 /2 M Li 2 SO 4 /LiNi 1/3 Mn 1/3 Co 1/3 O 2 delivers a discharge capacity of 116 mAh g −1 in the first cycle at an applied current of 0.2 mA cm −2 (C/5 rate ) and it retains a capacity of 107 mAh g −1 over 100 cycles with good rate capability. The non-aqueous cell, Li/1 M LiAsF 6 /EC-DMC/LiTi 2 (PO 4 ) 3 delivers a discharge capacity of 125 mAh g −1 with a voltage plateau around 2.4 V vs Li/Li + .

Advanced aqueous rechargeable lithium battery using nanoparticulate LiTi2(PO4)3/C as a superior anode

“…The absence of impurity peak implies the high purity of LTP phase in the samples. The measured lattice parameters of as-prepared samples in Table S1 are all in good agreement with those reported results2226. The microstructural features of as-prepared LTP/C-55 composite are shown in Fig.…”

“…Not all cathode materials possess the best stability in neutral electrolyte, for example, LiNi 1/3 Co 1/3 Mn 1/3 O 2 is more stable in Li 2 SO 4 solution with pH = 11 due to less H + co-intercalation7. LiFePO 4 and LiMn 2 O 4 could cycle stably in neutral aqueous electrolyte2122. Accordingly, in view of its relatively high intercalated potential, low cost and excellent cycling stability in lithium-containing solution, commercial LiMn 2 O 4 was directly used in the present work as the cathode.…”

“…LiTi 2 (PO 4 ) 3 (LTP) reacts electrochemically with lithium at 2.5 V vs. Li + /Li for Ti 4+ /Ti 3+ couple and Li ions occupy the octahedral interstitial sites representing M(1) within the LTP structure (space group R 3 c )22. Although LTP possesses excellent operating potential, flat voltage plateau as well as relatively high chemical stability in aqueous electrolytes, the conductivity of pure LTP has been found to be relatively low for practical use23.…”

Long-lived Aqueous Rechargeable Lithium Batteries Using Mesoporous LiTi2(PO4)3@C Anode

“…The diffraction peaks can be well indexed into LiTi 2 (PO 4 ) 3 phase with a rhombohedral NASICON type structure and a R 3 c space group (JCPDS#35–0754). The measured lattice parameters a  = 0.8464 nm and c = 2.1442 nm are in good agreement with the previous reports2829. The calculated average crystal size of LiTi 2 (PO 4 ) 3 from XRD pattern based on the Debye-Scherrer equation is 32.7 nm.…”

Review Article: Flow battery systems with solid electroactive materials

“…132 The high redox potential ($1.8 V versus Li/Li þ ) is beneficial to minimize hydrogen evolution and enables using this material in an aqueous electrolyte; however, in an organic system, the sacrifice in cell voltage would make this material unlikely to be chosen over other Ti-containing materials. 316 Silicon is a Li-ion anode material under active research and development with a high theoretical capacity (3590 mA h g À1 by forming Li 15 Si 4 , $10 times higher than graphite, the most commonly used anode material). 290,317 A mixture of silicon and carbon in organic electrolyte was cycled showing a large capacity and low polarization.…”