Paper-Based Ultra-High-Capacity Lithium-Ion Cell for Flexible Electronics

Flexible, ultra-thin, lightweight energy storage and conversion devices as power sources are in high demand for use in flexible, portable and wearable electronic devices with unusual shape diversity1. Among various power source systems for flexible electronic devices, flexible lithium-ion batteries have attracted great attention due to their high specific energy, high specific power, long cycle life and environmental friendliness2. However, conventional lithium-ion batteries with fixed sizes and shapes can be electrically shorted or cause fire/explosion when bent or stretched. To meet growing demands for flexible batteries, we take an unique approach where a layer-by-layer (LbL) deposited CNT paper-based current collector is used for both anode and cathode to enable flexibility of the cell. In addition, a gel-polymer electrolyte is used to minimize the amount of liquid electrolyte in the system, and a V2O5/graphene composite (specific capacity: 438 mAh/g) and a silicon/graphene based material (specific capacity: >1000 mAh/g) are used as the cathode and anode materials, respectively. The resulting cell, with a flexible/bendable feature and high specific energy shows promise as a candidate power source for flexible electronic devices. ADDIN EN.REFLIST (1) Gates, B. D. Science 2009, 323, 1566. (2) Zhou, G.; Li, F.; Cheng, H.-M. Energy & Environmental Science 2014, 7, 1307. Figure 1