Open AccessDifferentiated Lithium Salt Design for Multilayered PEO Electrolyte Enables a High‐Voltage Solid‐State Lithium Metal Battery
Author(s) -
Wang Chen,
Wang Tao,
Wang Longlong,
Hu Zhenglin,
Cui Zili,
Li Jiedong,
Dong Shanmu,
Zhou Xinhong,
Cui Guanglei
Publication year - 2019
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201901036
Subject(s) - materials science , electrolyte , anode , electrochemistry , battery (electricity) , electrochemical window , ionic conductivity , cathode , chemical engineering , lithium metal , polarization (electrochemistry) , oxide , lithium (medication) , capacity loss , lithium battery , lithium ion battery , electrode , ionic bonding , chemistry , ion , metallurgy , medicine , power (physics) , physics , organic chemistry , quantum mechanics , engineering , endocrinology
Low ionic conductivity at room temperature and limited electrochemical window of poly(ethylene oxide) (PEO) are the bottlenecks restricting its further application in high‐energy density lithium metal battery. Herein, a differentiated salt designed multilayered PEO‐based solid polymer electrolyte (DSM‐SPE) is exploited to achieve excellent electrochemical performance toward both the high‐voltage LiCoO 2 cathode and the lithium metal anode. The LiCoO 2 /Li metal battery with DSM‐SPE displays a capacity retention of 83.3% after 100 cycles at 60 °C with challenging voltage range of 2.5 to 4.3 V, which is the best cycling performance for high‐voltage (≥4.3 V) LiCoO 2 /Li metal battery with PEO‐based electrolytes up to now. Moreover, the Li/Li symmetrical cells present stable and low polarization plating/stripping behavior (less than 80 mV over 600 h) at current density of 0.25 mA cm −2 (0.25 mAh cm −2 ). Even under a high‐area capacity of 2 mAh cm −2 , the profiles still maintain stable. The pouch cell with DSM‐SPE exhibits no volume expansion, voltage decline, ignition or explosion after being impaled and cut at a fully charged state, proving the excellent safety characteristic of the DSM‐SPE‐based lithium metal battery.