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Hu, Pu

Publications and source records attributed to Hu, Pu.

4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Stabilizing the Interface between Sodium Metal Anode and Sulfide-Based Solid-State Electrolyte with an Electron-Blocking Interlayer

Sulfide-based Na-ion conductors are promising electrolytes for all-solid-state sodium batteries (ASSSBs) because of high ionic conductivity and favorable formability. However, no effective strategy has been reported for long-duration Na cycling with sulfide-based electrolytes because of interfacial challenges. Here we demonstrate that a cellulose–poly(ethylene oxide) (CPEO) interlayer can stabilize the interface between sulfide electrolyte (Na 3 SbS 4 ) and Na by shutting off the electron pathway of the electrolyte decomposition reaction. In conclusion, we achieved stable Na plating/stripping for 800 cycles at 0.1 mA cm –2 in all-solid-state devices at 60 °C.

25 ENERGY STORAGE↗
DOE OSTI2018

Tailored Organic Electrode Material Compatible with Sulfide Electrolyte for Stable All‐Solid‐State Sodium Batteries

Abstract All‐solid‐state sodium batteries (ASSSBs) with nonflammable electrolytes and ubiquitous sodium resource are a promising solution to the safety and cost concerns for lithium‐ion batteries. However, the intrinsic mismatch between low anodic decomposition potential of superionic sulfide electrolytes and high operating potentials of sodium‐ion cathodes leads to a volatile cathode–electrolyte interface and undesirable cell performance. Here we report a high‐capacity organic cathode, Na 4 C 6 O 6 , that is chemically and electrochemically compatible with sulfide electrolytes. A bulk‐type ASSSB shows high specific capacity (184 mAh g −1 ) and one of the highest specific energies (395 Wh kg −1 ) among intercalation compound‐based ASSSBs. The capacity retentions of 76 % after 100 cycles at 0.1 C and 70 % after 400 cycles at 0.2 C represent the record stability for ASSSBs. Additionally, Na 4 C 6 O 6 functions as a capable anode material, enabling a symmetric all‐organic ASSSB with Na 4 C 6 O 6 as both cathode and anode materials.

Chi, Xiaowei↗
DOE OSTI2016

Boron Substituted Na 3 V 2 (P 1 -x B x O 4 ) 3 Cathode Materials with Enhanced Performance for Sodium-Ion Batteries

The development of excellent performance of Na-ion batteries remains great challenge owing to the poor stability and sluggish kinetics of cathode materials. Herein, B substituted Na 3 V 2 P 3–x B x O 12 (0 ≤ x ≤ 1) as stable cathode materials for Na-ion battery is presented. A combined experimental and theoretical investigations on Na 3 V 2 P 3–x B x O 12 (0 ≤ x ≤ 1) are undertaken to reveal the evolution of crystal and electronic structures and Na storage properties associated with various concentration of B. X-ray diffraction results indicate that the crystal structure of Na 3 V 2 P 3–x B x O 12 (0 ≤ x ≤ 1/3) consisted of rhombohedral Na 3 V 2 (PO 4 ) 3 with tiny shrinkage of crystal lattice. X-ray absorption spectra and the calculated crystal structures all suggest that the detailed local structural distortion of substituted materials originates from the slight reduction of V–O distances. Na 3 V 2 P 3-1/6 B 1/6 O 12 significantly enhances the structural stability and electrochemical performance, giving remarkable enhanced capacity of 100 and 70 mAh g -1 when the C-rate increases to 5 C and 10 C. Spin-polarized density functional theory (DFT) calculation reveals that, as compared with the pristine Na 3 V 2 (PO 4 ) 3 , the superior electrochemical performance of the substituted materials can be attributed to the emergence of new boundary states near the band gap, lower Na + diffusion energy barriers, and higher structure stability.

36 MATERIALS SCIENCE↗