Since 2010, the cost of lithium-ion battery packs for electric vehicles has dropped 60%, from $1000 to $400 per kilowatt-hour (kWh) according to analysis by BNEF. At the same time, concerns regarding urban air pollution and our need to deploy zero emission vehicles in these cities are increasing. Melissa C. Lott takes a closer look at how EVs could help – and what the limitations might be.

Energy storage has been touted as the enabler of high levels of intermittent renewables in the electricity system – the silver bullet or Holy Grail for solar and wind. A key attribute for the technology’s deployment will be scalability, writes Melissa Lott.