Two experts with the Department of Energy's high-risk, high-reward research outfit look at the evolution and future of lithium-ion batteries.
In 1987, Nokia launched its first handheld mobile phone, the Mobira Cityman. The Cityman weighed in at about 2 pounds, packed a single hour of battery life, and cost thousands of dollars. While utterly revolutionary at the time, our kids today would not even recognize this ancient behemoth.
One of the things that allowed us to move from the brick-like cell phones of the '80s to the pocket-sized smart phones of today was the lithium ion battery. The lithium ion battery was first commercialized by Sony in 1991, and has since proven to be a revolutionary advance against a historical backdrop of snail's pace development in batteries. To get a sense for just how revolutionary lithium ion has been, consider that the nickel-cadmium ("NiCad") battery which powered the Cityman was barely half the size and weight of the first rechargeable battery technologies ever commercialized in the 1800s. In contrast, a mere 20 years of lithium ion development has driven nearly a 5-fold improvement, and at a significantly lower cost point.
Lithium ion technology was pivotal in the transformation to small, lightweight, and low-cost portable electronics. Now, that same battery technology is aimed at a new transformation: bringing electric vehicles (EV's) to the masses. This new transformation has already begun, with the first mass-produced EV's coming off production lines right now. But while these cars are comfortable, reliable, elegant, and a joy to drive, they are not yet ready for the masses.
It takes a lot more energy to drive your car than your iPhone. So even with the latest lithium ion batteries, equipping a vehicle with 100 miles of electric driving range requires a battery pack that costs upwards of $15,000, weighs about 500 pounds, and takes up a lot of precious space. As a result, the electric range of most new EV's is low, considering that most of us are used to being able to drive several hundred miles on a full tank of gas.
Cost and driving range in today's EV's pose two significant drawbacks to the average consumer. But not all vehicles are purchased by the average consumer. While an expensive battery adds sticker shock to a vehicle's price tag, it turns out that the savings gained by filling up your tank with cheap electricity rather than gas can make back the difference over the life of the vehicle. Factor in the fact that electric drive trains have nearly maintenance-free operation, and the total savings can make the EV a cheaper option even today. This basic arithmetic has driven corporations and municipalities across the world to consider EV's for their vehicle fleets, where amortized lifetime costs are essential and well-defined routes allow batteries to be sized for minimal cost. Recent electric fleet announcements by the likes of FedEx and General Electric indicate that fleets will be an important early market for EV's. Meanwhile, there seems to be no immediate shortage of individuals lining up to buy the first EV's from the likes of GM, Nissan, and Tesla Motors. Motivated by this strong early customer base, at least 20 manufacturers have announced plans to bring EV's to market in the next few years.