High-Throughput Electrospinning System| Scalable and Ultrathin Dual Entangled Network PolymerElectrolytes for Safe Solid-State Sodium Batteries

Academician Chen Zhongwei from Dalian Institute of Chemical Physics, Angew (IF 16.1): Scalable and Ultrathin Dual-Network Polymer Electrolytes for Safe Solid-State 

Sodium Batteries

Challenge: Ultrathin flexible solid-state electrolytes with high ionic conductivity and low interfacial resistance are crucial for the scalable production of solid-state sodium (Na) metal batteries (SSMBs). However, challenges including poor processing scalability, insufficient intrinsic mechanical strength, and limited ion transport capability remain unresolved.

Approach: Academician Chen Zhongwei's team at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences successfully developed dual-network polymer electrolytes (PAPE SSEs) with a thickness of only 9.7 μm through array multi-nozzle electrospinning combined with swelling hot-pressing process. The electrolytes demonstrate excellent voltage resistance, enhanced tensile strength, and outstanding thermal stability.

Innovation 1: The dual-network design combines PAN's rigid skeleton with Pebax's flexible segments. Ether oxygen groups (C-O-C) and cyano groups (C≡N) synergistically construct fast ion channels, achieving room-temperature ionic conductivity of 7.9×10⁻⁴ S·cm⁻¹ (3.4 times higher than pure PAN) with low activation energy of 0.105 eV, supporting stable battery operation across a wide temperature range (-30 to 65°C).

Innovation 2: PAPE SSEs exhibit tensile strength of 12.4 MPa and Young's modulus of 41.9 MPa, effectively suppressing sodium dendrite growth. Symmetric cells show stable cycling for over 500 hours at 3.2 mA cm⁻² critical current density. Furthermore, they show no shrinkage at 300°C with thermal decomposition onset temperature reaching 297.5°C, far exceeding commercial separators and significantly improving battery safety.

Innovation 3: When paired with high-loading cathodes (14.2 mg cm⁻²), the batteries deliver areal capacity of 1.7 mAh cm⁻² with 91.1% capacity retention after 100 cycles. The assembled pouch cells achieve energy density of 181.1 Wh kg⁻¹ and pass nail penetration, bending, and open-flame tests, demonstrating exceptional safety.

https://doi.org/10.1002/anie.202505938