BCG has released a study concluding that the long-term cost target for electric-car batteries — $250 per kilowatt-hour (kWh) — is unlikely to be achieved in the next decade without a breakthrough:
Most electric cars in the new decade will use lithium-ion batteries, which are lighter and more powerful than the nickel-metal hydride (NiMH) batteries used today in hybrids like the Toyota Prius. Citing the current cost of similar lithium-ion batteries used in consumer electronics (about $250 to $400 per kWh), many original-equipment manufacturers (OEMs) hope that the cost of an automotive lithium-ion battery pack will fall from its current price of between $1,000 and $1,200 per kWh to between $250 and $500 per kWh at scaled production. BCG, however, points out that consumer batteries are simpler than car batteries and must meet significantly less demanding requirements, especially regarding safety and life span. So actual battery costs will likely be higher than what carmakers predict.
Weight is also an issue. Randall Parker notes that the 400+ lb battery in the Chevy Volt provides 40 miles of range on electric power. That doesn’t scale well:
To go 200 miles in electric power would require 2000 lb just for the battery. Forget about the typical car’s 400+ mile range until battery energy density goes up by some multiple.
If current prices are $1,000 to $1,200 per kWh, what does that mean?
To put that in perspective a compact or midsize car might use a quarter of a kWh per mile. So at current prices a 100 mile range will require 25 kWh or at least $25,000. The cost is worse than that since batteries are not typically allowed to run all the way down.
And, again, that 100-mile ranges doesn’t simply cost $25,000; it also mean lugging 1,000 pounds of batteries along for the ride. That doesn’t help mileage.
Batteries are extremely expensive, not just in dollars per kWh, but also in pounds per kWh, even if the electricity they store is fairly inexpensive per kWh. Gasoline stores tremendous energy for its weight.
Thus, if you’re going to include both a gasoline generator and batteries, as in a Chevy Volt, you should only carry enough electricity in battery form to get you to work (and maybe back, if you can’t charge there). Any storage you don’t need on a more-or-less daily basis is a waste of money and a waste of energy, because those extra batteries don’t carry themselves.