How often do you have to replace the battery? Will it be recycled? Can you charge a battery even if it is not empty? How many charging cycles can the battery handle? Is it true there's a worldwide shortage of lithium?
Lithium-ion batteries can be found in all kinds of consumer products, from laptops to cell phones, and they also will be the power source in at least the first generation of electric cars -- an EV battery is really just a cluster of thousands of cell phone batteries packaged together.
"If I want to buy an electric vehicle, I would want to know how many miles can I drive under REAL driving conditions, how long will my battery last and how long will the battery take to charge," said Venkat Srinivasan, a staff scientist at the Lawrence Berkeley National Lab who writes a popular battery blog at www.thisweekinbatteries.blogspot.com.
The plug-in hybrid Chevy Volt and all-electric Nissan Leaf, the first mainstream plug-ins to reach the market, both offer battery warranties good for 100,000 miles or eight years. That will reassure many consumers, but there still are things they can do to maximize battery life and performance.
"Don't keep continuously fully charging and discharging them," Srinivasan said. "Pressing on the accelerator too much also draws power from the battery at a high rate, and can cause degradation."
Sunil M. Chhaya, an electric drive expert at EPRI, the Electric Power Research Institute, notes that batteries age faster if the temperature of the battery is frequently elevated, and EPRI research has found that heat management inside the batteries is the single most important predictor of battery health and longevity. That's one reason why Tesla uses a liquid cooling system to maximize the life of its battery packs.
"Batteries are like people and perform nicely when their operating temperature is in a 20-45 degrees Celsius (or 68-113 degrees Fahrenheit) window," Chhaya said. "Outside of it, they need to be 'thermally managed,' either by efficient inflow (if the batteries are cold) or outflow (if batteries are hot) of heat with a well-designed thermal system."
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