Recently, safety issues associated with the practical application of lithium–sulfur (Li–S) batteries have attracted tremendous concern. Herein, a nonflammable 3D porous framework is constructed from functional boron nitride nanosheets (f-BNNSs) supported on a scaffold of continuous functional carbon nanotubes (f-CNTs) as a bifunctional host for Li–S batteries. The unique 3D porous structure with high thermal conductivity provides a well-distributed heat field with smooth and ultrafast heat-conduction channels during continuous battery operation even at a high temperature, thereby ensuring timely and effective heat transfer and avoiding the thermal runaway caused by accumulated heat and excessive local temperature. The incombustible f-BNNSs act as a physical flame-retardant barrier to prevent the occurrence and spread of combustion. In addition, the uniform electric field with low local current density inhibit the growth of Li dendrites, avoiding the excessive local temperature caused by the formation of an uneven thermal field. The abundant polar functional groups effectively suppress polysulfide shuttling, reducing the extra heat accumulation generated by severe electrode polarization. This work provides a “two-in-one” strategy for realizing high-safety batteries via a “prevention and post-treatment” method that combines thermal field regulation and flame retardancy, and thus promotes the commercial development of Li–S batteries.

最近，与锂硫（Li-S）电池实际应用相关的安全问题引起了极大的关注。在此，不可燃的 3D 多孔框架由功能性氮化硼纳米片 (f-BNNSs) 构成，其支撑在连续功能性碳纳米管 (f-CNTs) 支架上，作为 Li-S 电池的双功能主体。独特的高导热3D多孔结构提供均匀的热场，即使在高温下连续运行电池时，也能提供光滑和超快的热传导通道，从而确保及时有效的传热，避免因积热而导致的热失控以及局部温度过高。不可燃的 f-BNNS 作为物理阻燃屏障，防止燃烧的发生和蔓延。此外，低局部电流密度的均匀电场抑制了锂枝晶的生长，避免了不均匀热场的形成导致局部温度过高。丰富的极性官能团有效抑制多硫化物穿梭，减少电极严重极化产生的额外热量积累。该工作通过结合热场调节和阻燃的“预防和后处理”方法实现高安全性电池的“二合一”策略，从而促进了锂硫电池的商业化发展。丰富的极性官能团有效抑制多硫化物穿梭，减少电极严重极化产生的额外热量积累。该工作为通过结合热场调节和阻燃的“预防和后处理”方法实现高安全性电池提供了一种“二合一”策略，从而促进了锂硫电池的商业化发展。丰富的极性官能团有效抑制多硫化物穿梭，减少电极严重极化产生的额外热量积累。该工作为通过结合热场调节和阻燃的“预防和后处理”方法实现高安全性电池提供了一种“二合一”策略，从而促进了锂硫电池的商业化发展。