Once a week, the U.S Department of Energy puts out its "Fact of the Week" and often times the fact is focused on plug-in electric cars.
Such is the case with the "Fact of the Week" release, focusing on the total batter capacity increase for plug-in electric vehicles in 2015"
TOTAL BATTERY CAPACITY OF ALL PLUG-IN ELECTRIC VEHICLES SOLD INCREASED FROM 2014 TO 2015
The number of battery packs sold for plug-in electric vehicles (PEV) declined by 3.4% from 2014 to 2015. However, the total battery capacity for all PEVs sold between 2014 and 2015 increased by 22.6%. The rising battery capacities of PEV models have increased battery production even when sales of battery packs are down. Following the introduction of mass market PEVs in 2011, the total battery capacity sold increased nearly tenfold from 0.4 to 3.8 million kW-hrs by 2015.
The sales volume of hybrid electric vehicles (HEV), and therefore HEV battery packs, is much higher than for PEVs but their battery capacities are much smaller. Battery capacities for 2011-2015 HEV models usually ranged from about 1 to 2 kW-hrs while PEV models for this same period had battery capacities as large as 90 kW-hrs for a single battery pack. As a result, the total battery capacity sold for PEVs is much higher than it is for HEVs despite lower PEV sales volumes.
In addition to the brief release, the DoE compiled a couple of nifty charts.
NUMBER OF VEHICLE BATTERY PACKS AND CAPACITY SOLD, 2011-2015