Seamless Integration of an Elastomer with Electrode Matrix and its In‐Situ Conversion into a Solid State Electrolyte for Robust Li‐Ion Batteries

Abstract

A unique way of robustly integrating an elastomer film onto a graphitic anode and then post process it into a solid‐state electrolyte for lithium‐ion battery applications is reported. The mutual solvability of the elastomer and the binder of the graphitic anode (carboxymethyl cellulose, (CMC)) in dimethylformamide facilitates the fusion of the two heterogeneous layers. Dimensional dynamics evolved during the integrated elastomer conversion into a solid electrolyte by liquid electrolyte uptake reveal a notable preferential uniaxial elongation along the normal plane. In contrast, the non‐integrated counterpart elongates along the transversal axis. These elastomer exhibits high ionic conductance (≈10–2 S cm−1). Half‐cells constructed with our electrolyte integrated electrode exhibit magnificent reduction and oxidation (REDOX) behavior. The efficient charge transfer across the snugly confined semi‐solid electrolyte/electrode interface layer leads to a high rate capability of 0.31 mAh cm−2 (41 mAh g−1) at 2 C which is double that of a graphitic conventional half‐cell. Unlike regular graphitic electrodes which degrade over time, this electrode remains robust, thanks to its propensity to retain its inherent elasticity. This work demonstrates a facile and scalable paradigm, in fabrication of flexible electrolytes that can easily be integrated to 3D devices and opens opportunities for developing, structurally conformable batteries of varied geometries.

Effect of polyacrylonitrile on triethylene glycol diacetate-2-propenoic acid butyl ester gel polymer electrolytes with interpenetrating crosslinked network for flexible lithium ion batteries

“…Compared to dried solid polymer electrolytes [6,7], gel polymer electrolytes (GPE) [8e10], formed by immersing large amount of liquid organic electrolytes into polymer frameworks, have received increasing attention in the flexible LIBs due to their high ionic conductivities on the order of 10 À3 S cm À1 at ambient temperature. Various polymer matrices, such as polyethylene oxide (PEO) [11,12], polyacrylonitrile (PAN) [13,14], polyvinylidene fluoride (PVDF) [15e17], poly(vinylidene fluoridehexafluoro propylene) (PVDF-HFP) [18,19], polymethylmethacrylate (PMMA) [20,21], polyimide (PI) [22,23], poly(urethane) (PU) [24,25] and etc., have been widely developed as candidate materials for the preparation of polymer electrolytes. Especially, PAN have been developed and attracted as the main component for applications not only in electric double layer capacitors [26,27], but also in LIBs [28,29].…”

An Ionic Liquid/Poly(vinylidene fluoride‐co‐hexafluoropropylene) Gel‐Polymer Electrolyte with a Compatible Interface for Sodium‐Based Batteries

“…However, these energies sources are unstable and discontinuous, making them difficult to use directly. [5][6][7][8] Gel-polymer electrolytes (GPEs) are more safe compared with liquid electrolytes by avoiding leakage of electrolytes, and the room-temperature ionic conductivity are 10 À 4 À 10 À 3 S cm À 1 due to the plasticizers. On the basis of their wide availability and affordability, sodium ion batteries (SIBs) are considered to be expected future alternates to lithium ion batteries.…”

“…Nevertheless, the low ionic conductivity and unsatisfactory interface contact between electrolyte and electrodes are the main problems. [5][6][7][8] Gel-polymer electrolytes (GPEs) are more safe compared with liquid electrolytes by avoiding leakage of electrolytes, and the room-temperature ionic conductivity are 10 À 4 À 10 À 3 S cm À 1 due to the plasticizers. [9] In addition, GPEs provide more excellent flexibility and processability compared with solid electrolyte.…”

Fibrous gel polymer electrolyte for an ultrastable and highly safe flexible lithium‐ion battery in a wide temperature range

“…17,18 Moreover, GPEs also have good flexibility and high ionic conductivity, which are suitable for practical applications in flexible LIBs. 19 However, the current LIBs using GPEs usually adopt the three-layer superposition preparation technology of a cathode, an anode, and GPEs. In particular, the interface affinity between GPEs and electrodes is poor during battery bending, which results in the large internal resistance of the battery system and degradation of electrochemical performance.…”