Energy consumed in transportation has been the focus of a number of recent posts here, including one contemplating the use of smiley faces to help drivers understand the impact of their behavioral choices, and one exploring why the cost-benefit balance is tipped against the purchase of a hybrid car based on fuel savings alone. Another big issue to consider with either a hybrid or an all-electric vehicle is the battery, which necessarily needs to pack a lot of charge, both by being large and, increasingly, by using metals like lithium.
How a lithium-ion battery works: This illustration shows the inner workings of a lithium-ion battery. When delivering energy to a device, the lithium ion moves from the anode to the cathode. The ion moves in reverse when recharging. Compared to other rechargeable batteries, lithium-ion batteries can store more energy in smaller, lighter packages. This unsurpassed energy-to-weight ratio make them the battery of choice for consumer electronics like cell phones and laptops, but also a great fit for electrified vehicles. Illustration and text courtesy Argonne National Laboratory and was accessed on Flickr.
A recent post about the prevalence of rare earth metals highlighted how much there is to know about the components used to make current vehicles based on new technologies, like hybrid drive trains. Massive supplies of elements like lithium are going to be key to permit scale-up of hybrid and all-electric vehicles requiring lithium batteries. Supply can come from mining operations, as well as recycling. An article a few days ago in the NY Times Business section highlighted the reality that there is no consensus on how electric car batteries should be recycled or reused.
A quote from the article by Ghislain Van Damme, a representative of one the world’s largest recyclers in Belgium, hits the nail on the head: “There is no green car without green recycling.”
Many who buy a hybrid or electric vehicle do so to lower their footprint, be it measured in energy or carbon emissions. When it comes to the battery, such consumers probably need to have a good idea of what will become of the battery when its lifetime in the vehicle is reached, especially because the destiny of these batteries is often manged by the car maker.
For example, the NY Times article mentions that Nissan Motor, maker of the all-electric Leaf, and General Motors, maker of the new plug-in hybrid Volt, are in discussions with power companies to reuse old batteries from their cars as part of the energy grid, perhaps storing intermittent renewable energy, such as that from wind or solar installations.
This sounds good on the surface, but it raises a key question: should we be using high-value elements like lithium in grid storage where space is most likely not a primary driver like it is in a vehicle? If not, then routing used batteries containing lithium to grid storage rather than recycling will have a non-trivial impact on the overall energy footprint of the cars from which they came. Understanding that full “life-cycle” of batteries is essential for understanding a hybrid or all-electric vehicle’s energy or carbon footprint.
Consumers need good information about the lifecycle of the components in their vehicles in order to make decisions that ultimately help them achieve their goals.
Note: thumbnail image from exfordy on Flickr.