The separator plays an important part in battery safety and performance. Polyolefin separators are widely used in commercial Lithium-ion batteries (LIBs), owing to their excellent properties, but they suffer from serious thermal shrinkage and poor electrolyte wettability. Thus, a multilayer separator (ASPESA) is developed by coating two thin layers of low-density polyethylene (LDPE) and Al₂O₃ on both sides of a polyethylene membrane using a facile and environmentally friendly casting technique. The ASPESA separator demonstrates a shutdown function at 120 °C and shows enhanced thermal stability under 185 °C, with a small thermal shrinkage of 1%. Meanwhile, the LDPE and Al₂O₃ layers can improve the electrolyte wettability and electrolyte uptake (407.23%). The multilayer ASPESA separator delivers an excellent cycle performance in LiFePO₄||Li cells with a discharge capacity of 144.5 mAh g⁻¹ after 900 cycles, with a high-capacity retention of 98.9% (compared to the 5th cycle). Therefore, the multilayer ASPESA separator has great utilization potential as a high-safety separator in LIBs.

隔膜对电池的安全性和性能起着重要作用。聚烯烃隔膜因其优异的性能而广泛应用于商业锂离子电池（LIB）中，但其热收缩严重且电解质润湿性差。因此，通过使用简便且环保的铸造技术，在聚乙烯膜的两侧涂覆两层低密度聚乙烯（LDPE）和Al ₂ O _{3薄层，开发了多层隔膜（ASPESA）。}ASPESA隔膜在120°C下表现出关断功能，并在185°C下表现出增强的热稳定性，热收缩率仅为1%。同时，LDPE和Al ₂ O ₃层可以提高电解液润湿性和电解液吸收率(407.23%)。多层ASPESA隔膜在LiFePO ₄ ||Li电池中表现出优异的循环性能，900次循环后放电容量为144.5 mAh g ^-1，容量保持率为98.9%（与第5次循环相比）。因此，多层ASPESA隔膜作为LIB中的高安全隔膜具有巨大的应用潜力。