A Nissan Leaf EV would use about 20 pounds of lithium in its 24 kWh battery packs. A Chevy Volt uses about 15 pounds. A Prius battery pack holds just 1.5 kWh of electricity, but uses no lithium.

Now consider Deutsche Bank’s estimate that the global 2015 battery-making capacity is 36 million kWh. The amount of capacity would yield enough battery packs for 1.5 million EVs of the Nissan Leaf type; 2.25 million pa
cks for a Chevy Volt plug-in hybrid type; and 24 million battery packs for a Prius-type vehicle.

How much gasoline does each type of vehicle save when applied over a global fleet of those sizes for a year. Here’s a chart taken from an article in Batteries International magazine:

Vehicle                        Gasoline Saved                       CO2 Reduction
Type                             (million gallons)                    (million pounds)

EV (Leaf)                    600                                       9,403
PHEV (Volt)               765                                       12,859
HEV (Prius)               3,840                                    97,344

That’s a pretty startling result. By far the most effective use of battery manufacturing, both from a gasoline savings point of view and from a CO2 reduction point of view, is a hybrid electric vehicle such as the Toyota Prius. The net effect of 24 million vehicles much more than offsets the overall effects from either a pure EV or a PHEV.

What to make of all this? Lithium, though relatively expensive, is also available in sufficient quantities for the near term. But if the automobile fleet were to transition to large numbers of EVs, the demand for lithium would rise dramatically and so would the cost.

Crude oil is also becoming scarcer and the price of crude is also rising again, but there is almost certainly a decades-long supply of crude left in the ground. Getting it out will be costly, but if it used more efficiently (in higher mileage cars, for example), demand for crude could continue to fall moderating the price of gasoline somewhat.

Using gasoline i with battery packs addresses issues of both gasoline and lithium cost and availability, and meaningful reductions in CO2 emissions. The US may not become energy independent by following this course, but it will certainly rely less on imported oil without becoming hooked on foreign sources of lithium.

Paul Ausick