Sodium dendrite growth is responsible for short circuiting and fire hazard of metal batteries, which limits the potential application of sodium metal anode. Sodium dendrite can be effectively suppressed by applying mechanically robust electrolyte in battery systems. Herein, a composite gel polymer electrolyte (GPE) is designed and fabricated, mainly consisting of graphene oxide (GO) and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP). With the addition of an appropriate amount of GO content, the compressive Young's modulus of 2 wt% GO+PVDF-HFP (2-GPH) composite GPE is greatly enhanced by a factor of 10, reaching 2.5 GPa, which is crucial in the suppression of sodium dendrite growth. As a result, uniform sodium deposition and ultralong reversible sodium plating/stripping (over 400 h) at high current density (5 mA cm-2 ) are achieved. Furthermore, as evidenced by molecular dynamics simulation, the GO content facilitates the sodium ion transportation, giving a high ionic conductivity of 2.3 × 10-3 S cm-1 . When coupled with Na3 V2 (PO4 )3 cathode in a full sodium metal battery, a high initial capacity of 107 mA h g-1 at 1 C (1 C = 117 mA g-1 ) is recorded, with an excellent capacity retention rate of 93.5% and high coulombic efficiency of 99.8% after 1100 cycles.

中文翻译：

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机械稳定的凝胶聚合物电解质，用于超稳定的钠金属电池。

树枝状钠的生长是造成金属电池短路和火灾的原因，这限制了钠金属阳极的潜在应用。通过在电池系统中应用机械强度高的电解质，可以有效地抑制树枝状钠。在此，设计并制造了主要由氧化石墨烯（GO）和聚偏二氟乙烯-六氟丙烯（PVDF-HFP）组成的复合凝胶聚合物电解质（GPE）。通过添加适量的GO含量，可将2 wt％GO + PVDF-HFP（2-GPH）复合GPE的压缩杨氏模量提高10倍，达到2.5 GPa，这对于抑制钠树枝状晶体的生长。结果，在高电流密度（5 mA cm-2）下实现了均匀的钠沉积和超长的可逆钠电镀/剥离（超过400小时）。此外，正如分子动力学模拟所证明的那样，GO含量有助于钠离子的运输，提供了2.3×10-3 S cm-1的高离子电导率。在全钠金属电池中与Na3 V2（PO4）3阴极耦合时，在1 C（1 C = 117 mA g-1）时记录到的高初始容量为107 mA h g-1，具有出色的容量保持率在1100次循环后，其库仑效率为93.5％，库仑效率高达99.8％。