Details

Autor(en) / Beteiligte

• Kim, Jong Heon
• Jung, Ji‐Won
• Cho, Su‐Ho
• Kim, Il‐Doo
• Park, Yun Chang
• Seo, Dong‐Hwa
• Kim, Hyun‐Suk

Titel

Investigation of Ordering on Oxygen‐Deficient LiNi0.5Mn1.5O4‐δ Thin Films for Boosting Electrochemical Performance in All‐Solid‐State Thin‐Film Batteries

Ist Teil von

• Small (Weinheim an der Bergstrasse, Germany), 2022-06, Vol.18 (24), p.n/a

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2022

Quelle

Wiley Online Library All Journals

Beschreibungen/Notizen

• All‐solid‐state thin‐film batteries (ASSTFBs) are promising next‐generation battery systems, but critical challenges such as low‐energy‐density remain. The low‐energy‐density might persist with low‐voltage cathode material; hence, high‐voltage cathode material development is required. While LiNi0.5Mn1.5O4 (LNM) has been considered a promising high‐voltage cathode material. This study investigates the electrochemical properties of LNM thin films based on the correlation between the ordering of cations (Ni and Mn) and oxygen vacancies (VO). The authors find that the cations’ order changes from a disordered structure to an ordered structure with an increased oxygen flow rate during deposition. The optimized LNM fabricated using a 60:40 ratio of Ar to O2 exhibits the highest rate capability (321.4 mAh cm−3 @ 20 C) and most prolonged cycle performance for 500 cycles. The role of VO within the LNM structure and the lower activation energy of ordered LNM compared to disordered LNM through first‐principles density functional theory calculations is elucidated. The superior electrochemical performance (276.9 mAh cm−3 @ 0.5 C) and high cyclic performance (at 93.9%, 500 cycles) are corroborated by demonstrating flexible ASSTFB cells using LiPON solid‐state electrolyte and thin‐film Li anode. This work paves the way for future research on the fabrication of high‐performance flexible ASSTFBs. An LiNi0.5Mn1.5O4 (LNM) (100 nm)/LiPON (500 nm)/Al2O3 (1 nm)/Li (1 µm) all‐solid‐state thin‐film battery (ASSTFB) is successfully fabricated on flexible stainless steel substrate by reactive magnetron sputtering with superior electrochemical performance (276.9 mAh cm−3 @ 0.5 C) and high cyclic performance (cycle retention of 93.9% from the 1st cycle to the 500th cycle).