An In Situ Polymerized Li-S Battery Integrated with an Electrothermal Interlayer

Benefiting from the high theoretical energy density, low cost, and environmental protection, the lithium-sulfur (Li-S) battery is one of the most competitive candidates for the next generation of high-energy-density batteries. However, the rate and low-temperature performances are poor due to the terrible dynamics of the S cathode. Herein, a four-electrode Li-S cell integrated with an electrothermal interlayer is designed to realize the internal heating. An electrothermal interlayer composed of Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) and carbon nanotube (CNT) is prepared and displays fast, uniform, and adjustable heating ability under applied voltages of 15-30 V. The interlayer is also conducive to improving the wetting ability and thermal stability of the separator. Meanwhile, the Li⁺ ion conductivity and transfer number of the in situ polymerized electrolyte are enhanced after integrating the interlayer, especially at high temperatures.