An organic additive assisting with high ionic conduction and dendrite resistance of polymer electrolytes

Abstract

High-performance polymer electrolytes are desirable for developing solid-state lithium (Li) metal batteries (SSLMBs) with enhanced safety and high energy density; however, their applications are hindered by low ionic conductivity and...

Regulating Conductive Copolymerization Networks in the Polymer Electrolyte for High-Performance Quasi-Solid-State Lithium–Metal Batteries

“…With the adsorption of plasticizers, the swollen electrolyte membranes formed more amorphous regions to promote the movement of the polymer segments and improve the ionic conductivity within the polymer system, which will contribute to high ionic conductivity at ambient temperatures. 17 FTIR spectroscopy was performed on various test samples to investigate the chemical structures and interactions between the synthesized PVDF-HFP-based membranes and the raw materials; the results are shown in Figure 1a,b. Comparing the PVDF-HFP-F and PVDF-HFP-P in Figure 1a, the solvent-cast PVDF-HFP-F sample exhibits absorption bands at 835 and 1230 cm −1 , which are assigned to the C−N group symmetric and asymmetric stretching vibration of the residual DMF, respectively.…”

“…As for the PPA10, the C�C peak vanished but the C�O peak remained, suggesting that the AMPS have been fully copolymerized and the amide groups are retained in the as-synthesized PPA10. 17,28 To further verify the molecular structures of PPAx copolymers, 1 H NMR measurements were conducted on relevant electrolyte samples and monomers, and Figure 1c presents their spectra. In all specimens, the DMSO-d 6 solvent and water signals can be observed at 2.5 and 3.4 ppm, respectively.…”

“…The thin, transparent, and free-standing PPA x polymer membranes have been acquired through a simple solution-casting methodology. With the adsorption of plasticizers, the swollen electrolyte membranes formed more amorphous regions to promote the movement of the polymer segments and improve the ionic conductivity within the polymer system, which will contribute to high ionic conductivity at ambient temperatures …”

“…16 Nan and his co-workers employed a strategy to incorporate 1 wt % AMPS as an organic additive into the PVDF-substrate electrolyte that achieved a high ionic conductivity of 2.2 × 10 −4 S cm −1 at 26 °C, increased the number of Li + transference to 0.49, and effectively suppressed the growth of Li dendrites. 17 Therefore, the single-ion conduction salt PAMPSLi could function as the Li-ion source to improve the ionic conductivities and guarantee the rapid transportation of lithium ions in the polymer electrolytes. Despite many advantages in the quasi-solid-state or SIPE field, most polymer electrolytes with single-function still fail to satisfy the requirements for high safety and high energy density of LIBs due to the trade-off between electrochemical stability, mechanical strength, and thermal stability.…”

“…Distinguished from the conventional dual-ion system electrolytes, single-ion system electrolytes can promote cation shuttling by inhibiting the mobility of anions in copolymerized lithium salts, thereby alleviating the aforementioned adverse issues, improving the electrochemical performance of LIBs, and enhancing energy efficiency. , 2-acrylamido-2-methylpropanesulfonic acid (AMPS), a typically inexpensive solvent resistance comonomer, possesses multifunctional groups, the unsaturated CC bond for polymerization, amide groups (−CO–NH−) with high polarity for dissociation of lithium salt and sulfonate groups (−SO 3 ) for lithiation as single-ion conductor lithium salt in polymer electrolyte. , For instance, Jia and co-workers designed a serial of intriguing elastic single-ion polymer electrolytes (SIPEs) with Pluronic and AMPSLi, which exhibited an ionic conductivity of 1.10 × 10 –4 S cm –1 at 65 °C, an extended ESW (>5 V) and a high lithium transfer number ( t Li+ > 0.93) . Nan and his co-workers employed a strategy to incorporate 1 wt % AMPS as an organic additive into the PVDF-substrate electrolyte that achieved a high ionic conductivity of 2.2 × 10 –4 S cm –1 at 26 °C, increased the number of Li + transference to 0.49, and effectively suppressed the growth of Li dendrites . Therefore, the single-ion conduction salt PAMPSLi could function as the Li-ion source to improve the ionic conductivities and guarantee the rapid transportation of lithium ions in the polymer electrolytes.…”