Electrochemistry and the Future of the Automobile

Abstract

Electrification of the automobile provides a means of sustaining personal mobility in the face of petroleum resource limitations and environmental imperatives. Lithium ion (Li ion) batteries and hydrogen fuel cells provide pure-electrification solutions for different mass and usage segments of automotive application. Battery electric vehicles based on current and targeted Li ion battery technology will be limited to small-vehicle low-mileage-per-day applications; this is due to relatively low specific energy (kWh/kg) and long recharge time constraints. We briefly discuss new generations of Li ion positive and negative electrode intercalation compounds that are needed and under development to achieve energy storage density, durability, and cost targets. Lithium−air batteries give promise of extending the range, but scientists and engineers must surmount a plethora of challenges if growing research investments in this area are to prove effective. Hydrogen fuel cell vehicles have demonstrated the required ∼300 mile range and the ability to operate in all climates, but the cost of Pt-based catalysts, a low efficiency of utilization of presently cost-effective renewable sources of primary energy (e.g., electricity from wind), and the development of hydrogen infrastructure present significant challenges. Dramatic decreases in the amount of Pt used are required and are being brought to fruition along several lines of development that are described in some detail.