(348f) Increasing Power Density in Li-Ion Batteries Using Carbon Nanotube-Modified Interfaces

In recent years, remarkable progress in the development of Li-ion battery technology has led to devices that deliver records in power and energy density. High performance Li-ion batteries utilizing Lithium Iron Phosphate (LFP) typically require conductive coatings and advanced composites with carbon nanomaterials to increase electronic conductivity and power densities. However, these performance enhancements come at the expense of limited scalability and increased materials costs, and even with these improvements, high-power battery operation is still limited.

In this presentation, we describe a new approach to increasing the power density of Li-ion batteries by modifying the aluminum foil substrates with vertically aligned, multiwalled carbon nanotubes using a continuous, roll-to-roll CVD process. These easily processable, low cost electrodes lead to a lower cell resistance and an increased discharge potential, which provide higher charge capacities when operating with increased current densities relative to devices fabricated using conventional aluminum foil substrates. Compared to batteries comprising LFP cathodes on Al foil (122 Wh/kg, 863 W/kg), cells prepared using LFP on VACNT-modified Al foil provide increased power (1780 W/kg) while maintain high energy density (100 Wh/kg). This simple and scalable method to modifying electrode current collector substrates can be applied to various cathode and anode materials and chemistries, creating Li-ion batteries with superior rate capabilities.