A Supertough, Nonflammable, Biomimetic Gel with Neuron‐Like Nanoskeleton for Puncture‐Tolerant Safe Lithium Metal Batteries

Abstract

To overcome the critical safety and performance issues of lithium metal batteries, it is urgent to develop advanced electrolytes with multi‐defensive properties against fire, mechanical puncture, and dendrite growth simultaneously, in addition to high ion‐conductivity. However, realizing these essential properties by one electrolyte has proved to be extremely challenging due to the inherent conflicts among them. Herein, to circumvent this challenge, a neuron‐like gel polymer electrolyte (simply referred as Neu‐PE) to simultaneously achieve supertoughness, nonflammability, dendrite‐suppression capability and self‐driven property is reported. This Neu‐PE takes advantage of nano‐phase separation regulated by highly ion‐conductive deep‐eutectic solvent. As a result, the Neu‐PE holds high ambient ionic conductivity (1.27±0.09 mS cm−1), super‐toughness and strength (22.52 MJ m−3 and 13.5±0.6 MPa), fire resistance and importantly, lithium‐metal anode protection capability. Lithium metal batteries assembled with this multi‐defensive Neu‐PE can work normally even under metal‐probe puncture or serious damage by cutting.

Polymerizable Deep Eutectic Solvent-Based Polymer Electrolyte for Advanced Dendrite-Free, High-Rate, and Long-Life Li Metal Batteries

“…An electrolyte with superior mechanical properties was found to effectively promote the growth of lithium dendrites, thereby extending the battery life and enhancing safety. The tensile strength (∼6.1 MPa) and strain (∼31.5%) of GF@poly­(PDES) showed significantly improved performance compared to that of dry fiberglass fabric (GF) in Figure S9, GF@PDES electrolyte, and GF@commercial electrolyte …”

“…The tensile strength (∼6.1 MPa) and strain (∼31.5%) of GF@poly(PDES) showed significantly improved performance compared to that of dry fiberglass fabric (GF) in Figure S9, GF@PDES electrolyte, and GF@ commercial electrolyte. 39 The galvanostatic cycling of the symmetric Li||Li cell was assessed at 0.1 mA cm −2 to investigate the compatibility between the Li metal anode and the poly(PDES) electrolyte. According to the data in Figure S10, the cell using commercial electrolytes experienced significant voltage drops after 520 h, respectively, suggesting that Li dendrite growth caused short circuits.…”

Manipulating the Nanophase Separation of a Polymer–Salt Microfluid Generates an Advanced In Situ Separator for Component-Integrated Energy Storage Devices

“…For advanced separators, it is critical to achieve excellent wetting capability for a very broad range of liquid electrolytes (LEs), including traditional ones and developing ones, such as high-viscosity but nonflammable ionic liquid (IL) electrolytes and deep eutectic solvent (DES) based LEs. Actually, with the increasing demand on device safety, nonflammable LEs have been of great interest recently. − Unfortunately, these safe LEs are usually highly viscous and show a poor wetting behavior with traditional PP/PE separators. Therefore, achieving good wetting to these safe LEs has been challenging but critical for the development of safe batteries.…”

Mechanism of Bilayer Polymer-Based Electrolyte with Functional Molecules in Enhancing the Capacity and Cycling Stability of High-Voltage Lithium Batteries

“…It was notable that the σ i values of CSEs were lower than those of ASEs at the same temperature resulting from the high crystallinity of the PVDF substrate in CSEs. 31 Moreover, PVDF retained its crystal structure while PEO was in molten state at 60 °C, 33,34 which limited the σ i of the heterogeneous double-layer SPE. As the PEO matrix turns to be semimolten state above the glass transition temperature (60 °C), the subsequent electrochemical measurements would be conducted at 60 °C for high σ i values and desirable mechanical strength of the solid-state electrolyte.…”