Aerosol Spray Deposition of Carbon Nanotube Enhanced LiFePO4 Batteries

Batteries technologies with high power and high energy density seem to be inevitable exhibit poor battery life. Nevertheless, the need to solve our energy and transportation problems demands that we make materials that can both deliver high current densities and do it reliably over thousands of cycles. A failure mechanism within the composite of intercalation cathodes is the loss of electrode contact as the materials swell and crack during Lithiation and de-Lithiation. A well dispersed and stabilized conductive network of carbon nanotubes should alleviate this failure mechanism. Producing a well dispersed and well connected network of CNTs cannot be done with ball milling, the traditional battery mixing method, as the CNTs tend to be broken apart instead of dispersed. In this work we demonstrate an ultrasonication and aerosol deposition technique of CNTs, PVdF, and Lithium Iron Phosphate (LFP) that produces batteries that exhibit little capacity fade. Additionally, the inactive material content (10%) is drastically reduced compared to batteries made with carbon black (25%). Microanalysis demonstrates that the optimized aerosol method can produce composites with well dispersed and open networks of CNTs more effectively than slurry methods.