Scalable, Ultrathin, and High‐Temperature‐Resistant Solid Polymer Electrolytes for Energy‐Dense Lithium Metal Batteries

Abstract

The commercialization of rechargeable lithium-ion batteries (LIBs) has revolutionized the modern lifestyle, [1] leading society into an electrified, wireless, and sustainable future. With the continuous upsurge in demand for energy-dense devices, future advancement of batteries will require higher energy density, longer cycle life, and better safety. [2,3] Lithium metal anodes have a high specific capacity of ≈3800 mAh g −1 , [4,5] enabling the possibility of higher energy density batteries. However, commonly used liquid electrolytes in Li metal batteries (LMBs) often result in uncontrollable lithium dendrite growth, inadequate electrochemical and thermal stability, and high flammability. [2,4] As a result, limited performance and safety issues restrict the application and development of LMBs based on conventional liquid electrolytes.Compared to liquid electrolytes, solidstate electrolytes (SSEs) can potentially provide better safety, higher mechanical strength, and excellent chemical and electrochemical stability. [4,[6][7][8][9][10] SSEs can be grouped into three categories: inorganic solid electrolytes, [11][12][13][14] solid polymer electrolytes (SPEs), [15][16][17] and their hybrids. [18][19][20][21] Among them, inorganic solid electrolytes have the highest ionic conductivity [11] and excellent thermal stability, [2] but their interfacial compatibility, brittleness, and rigidity [22,23] are the challenges to be addressed towards their practical application. [9] In contrast, SPEs have good interfacial compatibility, [24] and excellent chemical and electrochemical stability, [18,24,25] but are lacking in thermal stability and mechanical strength, which generally makes them insufficient for meeting the requirements of high-safety and high-performance LMBs, [6,26,27] especially at high temperatures (>100 °C). [28] A hybrid of ceramic and polymer SSEs may offer good mechanical strength and safety, but it is still challenging to achieve ultrathin composite SSEs. Therefore, the design of a robust, ultrathin SSE that fulfills the above requirements is urgently needed.To achieve an energy density comparable to or larger than liquid electrolyte-based cells, ultrathin and lightweight solid electrolytes are necessary. [29,30] Compared to typical, thick ceramic electrolytes with thicknesses in the range of a few hundred microns, [14,[31][32][33] SPEs and their composites are easily engineered and manufacturable for tunable smaller All-solid-state batteries (ASSBs) demonstrate great promise, offering high energy density, good thermal stability, and safe operation compared with traditional Li-ion batteries. Among various solid-state electrolytes (SSEs), solid polymer electrolytes (SPEs) offer an attractive choice due to their thinness, low density, and good manufacturability. However, ultrathin SPEs that work with practical current densities or at high temperatures remain challenging, limiting applicable conditions of SPE-based batteries. Here, the authors report a novel scalable, ultrathin, and high-temperature-resistant ...

Effectively raising the rate performance and cyclability of a graphite anode via hydrothermal modification with melamine and its electrochemical derivatives

“…The C x N y derived from melamine can further react with Li + to produce Li 3 N, as has been confirmed by the literature. 39…”

Al2O3 Fiber-Reinforced Polymer Solid Electrolyte Films with Excellent Lithium-Ion Transport Properties for High-Voltage Solid-State Lithium Batteries

“…The XPS of Li sheets after cycling of Li/PPO SE/Li cells and Li/PPO-AFs/Li cells are shown in Figure e–h. The peaks of LiF and Li 3 N can be seen in the figure, which forms an SEI film between the lithium anode and the CSE to reduce the interfacial impedance and effectively suppress lithium dendrites. , However, the peaks of LiF and Li 3 N of PPO SE in the figure are higher than those of PPO-AFs, and too much LiF and Li 3 N generated at the interface will increase the interface impedance of the battery. This result just verifies the analysis of the impedance difference (Figure S3).…”

Alginate Fiber Grafted Polyetheramine Driven High Ion Conductive and Flame-Retardant Solid Polymer Electrolyte for Lithium Metal Batteries

“…Therefore, developing solid-state electrolytes (SSEs) that are not only ionic conductive but also nonvolatile, non ammable, and mechanically robust is crucial to fundamentally improve the safety characteristics of LMBs. Until now, several different types of SSEs have been developed, including inorganic solid electrolytes (ISEs) [4], solid polymer electrolytes (SPEs) [5] and organic-inorganic composite electrolytes [6][7][8][9][10]. Among the various SSEs, SPEs that are composed of polymer matrix and lithium salts exhibit high lithium ions (Li + ) conductivity, high exibility, facile processability, and excellent electrode/electrolyte interfacial compatibility.…”