Silicon Asymmetric Membranes for Efficient Lithium Storage: A Scalable Method

In this study, scalable membrane technologies are adapted to obtain silicon asymmetric membranes for lithium-ion battery anodes. The unique asymmetric porous structure can provide both mechanical support and free volume to accommodate the large volume expansion during silicon lithiation, thus leading to excellent rate and cycling performance. An overall specific capacity as high as 1500mAhg(-1) was achieved at 100mAg(-1). Even at 1000mAg(-1), the capacity was still above 800mAhg(-1). More than 90% of the initial capacity was retained after 200cycles. It was also observed that a lower Si content and higher carbonization temperature can help achieve stable cycling performance in general. This report is significant in terms of demonstrating a simplistic, generic, and scalable method to create a robust, porous asymmetric membrane structure for efficient lithium-ion storage.