關於hybrid/electric car battery的幾篇文章

1.Hybrid Car Batteries, Comparing NiMH and Lithium Ion Performance, Toxicity, and Recycling

After a growing call for environmental responsibility by the car-buying public, the auto industry is employing a number of non-lead battery alternatives in hybrid vehicles. Starting off slowly, hybrid vehicle sales have now topped the one million mark, with some of the older hybrid models' batteries in need of replacement. To accommodate for the number of hybrid vehicle batteries being disposed of in the near future, auto makers are developing recycling technology today. Not only will a fully operational recycling infrastructure be in place, but less toxic battery materials will be employed.

Illustration of Lithium-ion battery while charging

NiMH, or nickel metal hydride

The battery type most commonly used in hybrids, with a lower toxicity than lead, NiMH batteries will last a few years beyond their 8-10 year warranty before they fail. Toyota and Honda reclaim nearly 100 percent of their batteries' plastic, metal plates, cases, and wiring. In fact, Toyota, in an effort to reduce the number of its batteries ending up in land fills, offers a $200 return for every battery it receives.

Lithium-ion - available in limited numbers later this year

Panasonic EV Energy Co., which is jointly owned by Toyota and Panasonic Corp. is increasing production to meet the increased demand for hybrid car technology, especially the Toyota Prius in recent months. Their research department is working diligently to overcome the risk of overheating which resulted in the recall of millions of laptop computers from a few years ago.

Conserving Natural Resources by Increasing Energy Density

A measure of the efficiency of batteries is calculated in their energy to weight ratio or energy density, which is especially high in lithium ion batteries. The first plug-in electric car to ship with a Li-ion battery will be the Tesla Roadster which is due out this month. The weight savings and the energy density of the Li-ion battery over a comparable NiMH one is best exemplified by the fact that the Tesla would require a 1,000-Kg NiMH battery to replace the 400-Kg Li-ion currently standard in the Roadster.

Microprocessors, logic circuitry and sensors monitor and adjust current flow within the battery to virtually eliminate the risk of overheating and explosion. Passive design features of the battery protect it from damage due to collision or penetration by foreign object. The design also prevents anyone from accessing the high voltage connections within the battery. The U.S. Department of Transportation has also performed crush, vibration and collision testing to permit the battery from being installed in vehicles.

Illustration of Lithium-ion battery while discharging

Latest Research - Carbon Nanotube Batteries

Carbon nanotubes have been the subject of extensive research in which numerous potential applications are being explored. Chinese researchers at the Shenyang National Laboratory for Materials Science discovered that by coating the anode of a lithium ion battery with a nanotube membrane, they could extend the storage life and discharge capacity of the battery while decreasing the occurrence of overheating. The research points to the possibility of recharging lithium ion batteries in minutes, extending their life indefinitely, and cutting the cost of hybrid vehicles.

A Scarcity of Natural Resources

The availability of Lithium and the other raw materials required to manufacture Lithium-ion batteries is the subject of continued study by the Department of Energy. In a paper presented to the DOE by Argonne National Laboratory in May, 2009, the authors have concluded that the projected need for Lithium for Lithium-ion batteries in the U.S. will exceed world production levels at 25,000 tons by 2030. If fastidious recycling of spent batteries is carried out, the study also predicts that this need will never exceed world production. While Lithium use in manufacturing batteries only accounts for about 25 percent of the total industrial use, that percentage will rise.



2.Should we be Worried About Hybrid-Car Batteries?

We frequently hear it from hybrid-skeptics: "Ah, yes, nice car, fuel savings, etc, but wait until you have to pay to replace the batteries in a few years! Aren't these batteries polluting more than burning extra gas?" We always suspected that was BS and now and then an article seems to confirm it, but today it's HybridBlog's turn to tackle the subject with this post. They gathered from a few articles and by talking with carmakers that all the current big hybrid makers (Toyota, Honda, Ford) believe that their battery packs will last for the life of the vehicle.

"Toyota's own tests have run batteries for the equivalent of 150,000 miles with no discernible degradation, and the company expects them to last the useful life of the car." It's from a LATimes article that seems to have moved, and I can't find it in their archives.

"Honda Says Battery Pack in Hybrid Is Designed for Life of the Car." From here.

And the same from Ford, Toyota and Honda when HybridBlog checked directly with them, with the caveat that "they are sure someone will find a way to push a vehicle far enough that the battery may not last, but the same holds true for the engines, transmissions, and other components in any car or truck."

So yeah, nothing lasts forever, but "life of the car" is good enough for me.

Also, hybrid batteries are recycled:

Is there a recycling plan in place for nickel-metal hydride batteries?

Toyota has a comprehensive battery recycling program in place and has been recycling nickel-metal hydride batteries since the RAV4 Electric Vehicle was introduced in 1998. Every part of the battery, from the precious metals to the plastic, plates, steel case and the wiring, is recycled. To ensure that batteries come back to Toyota, each battery has a phone number on it to call for recycling information and dealers are paid a $200 "bounty" for each battery.

3.Lithium Battery Recycling Gets a Boost
The DOE funds a company that recycles plug-in vehicle batteries.

The US Department of Energy has granted $9.5 million to a company in California that plans to build America's first recycling facility for lithium-ion vehicle batteries.

Anaheim-based Toxco says it will use the funds to expand an existing facility in Lancaster, OH, that already recycles the lead-acid and nickel-metal hydride batteries used in today's hybrid-electric vehicles.

There is currently little economic need to recycle lithium-ion batteries. Most batteries contain only small amounts of lithium carbonate as a percentage of weight and the material is relatively inexpensive compared to most other metals.

But experts say that having a recycling infrastructure in place will ease concerns that the adoption of vehicles that use lithium-ion batteries could lead to a shortage of lithium carbonate and a dependence on countries such as China, Russia, and Bolivia, which control the bulk of global lithium reserves. "Right now it hardly pays to recycle lithium, but if demand increases and there are large supplies of used material, the situation could change," says Linda Gaines, a researcher at the Argonne National Laboratory's Transportation Technology R&D Center.

Toxco's DOE grant may seem like pocket change--last week the DOE awarded a total of $2.4 billion to companies developing batteries and systems for electric vehicles--but it's also early days for the project. Sales of plug-in hybrids and all-electric vehicles have yet to take off, and though President Barack Obama has pledged to get a million plug-in hybrids on US roads by 2015, it will likely be a decade before any large-scale recycling capability is required.

Demonstrating the capacity to recycle, however, will be key to showing that electric vehicles are truly "green"--both emission-free in operation and sustainable in design. "Management of these batteries has to be done in an environmentally responsible way and in an economic way," says Todd Coy, executive vice president of Kin*****ursky Brothers, Toxco's parent company.

Toxco also has an edge over newcomers to the market. The company is already North America's leading battery recycler and has been recycling single-charge and rechargeable lithium batteries used in electronics devices and industrial applications since 1992 at its Canadian facility in Trail, British Columbia. "We're managing the bulk of the batteries already out there," says Coy.

4.Li-ion battery recycling starts getting attention

Car batteries actually have the highest recycling rate of any waste product in the world. Since they are, effectively, blocks of valuable metals, it isn't hard to get someone to pay for them once they stop holding a charge. However, while that easily applies for lead-acid and nickel batteries currently being used in traditional and hybrid vehicles, it's not as simple for lithium ion batteries.

Lithium ion batteries just don't have much in them that is economically useful. Currently, lithium carbonate is pretty cheap stuff, and it just isn't economically viable to recover it from batteries. Of course, that could easily change. As more and more batteries are produced, the world's current capacity for lithium could easily be strained.

Additionally, from an environmental perspective, it would be really bad news to have a new kind of battery that no one wants to recycle. Even if it isn't economically viable, Li-ion batteries contain all kinds of weird stuff that we don't want leaching into the ground water.

Those are the two reasons why Toxco, a company that already recycles nickel and lead batteries, is getting into the Li-ion game. And, also, why the DOE just gave Toxco a $9.5M grant to develop lithium battery recycling technology.

Toxco has been recycling small lithium ion batteries for more than a decade already, but new chemistry and the possible bulk of vehicle batteries is requiring them to re-focus on lithium. Hopefully, recycling Li-ion batteries will soon be just as easy as recycling any other kind of car battery. If not, it will be harder to sell buyers on the "green" part of electric vehicles.

One thing I won't say is that we're just "trading one unstable fuel for another" and that soon we'll be dependant on unbalanced countries for our lithium. Lithium is not a fuel, it's way of storing power. It is not used up by car batteries and there is plenty of it in the world. Don't start worrying that lithium is the next crude oil, it's not, especially if we can get good recycling technology going.

5.When Electric-Car Batteries Die, Where Will They End Up?

A DECADE from now, owners of electric cars, having driven their share of clean and green miles, may encounter a dashboard light flashing an unwelcome message: Check Battery.

Their first concern, quite likely, will be the expense of a new battery, which could be $10,000 or more based on today’s prices, though production breakthroughs might lower costs by then.

But ecoconscious drivers will soon turn to the matter of a final resting place for their worn-out batteries. A bulky 500-pound lithium-ion battery pack will never be a candidate for curbside recycling. And improper disposal would undo the good accrued through years of zero-emissions motoring.

This situation is years away, of course. Few lithium-ion-powered cars are on the road, and estimates of the battery packs’ lifespan — no one knows for sure — range upward from seven years. Even so, battery suppliers and electric utilities are already working to establish a recycling stream.

Among the organizations hoping to create an afterlife for batteries that are no longer fit for road use is a Washington-based trade group, the Rechargeable Battery Association, which calls itself PRBA. The stakes are high for such efforts. All of the parties are hoping to be seen as conscientious product stewards so that electric cars have a chance to thrive. As well, they want to wring every last bit of value from the batteries before their raw materials are finally processed for recovery.

To grasp the good and bad of product stewardship, consider two common examples: tires and conventional lead-acid batteries.

Every year millions of worn-out tires are removed from America’s cars. About a third are retreaded or recycled, but many end up abandoned and hundreds of millions are in storage awaiting the arrival of an economically feasible use. Tires are banned from most landfills because they are bulky and trap pockets of methane. Lacking a viable end use, the bald tire is a prime example of poor product stewardship.

The gold standard of effective stewardship is the old-fashioned lead-acid car battery; according to the Battery Council International, a trade group based in Chicago, 97 percent of battery lead is recycled. In the last decade, major manufacturers like Exide Technologies have developed an infrastructure to minimize the chances of discarded batteries ending up in landfills.

“Shops that install new batteries and save the old ones for pickup are paid about $10 per core,” said Robert Hohman, a vice president at Complete Battery Source, a chain of retailers based in Brighton, Mich.

“Recyclers shred the hard parts — lead plates, plastic cases — and capture the acid electrolyte,” he said. “Nearly all of the recovered material goes into new batteries.”

The value of the metal in lead batteries, about 30 cents a pound according to Mr. Hohman, is in stark contrast to the value of the four pounds of lithium inside the 400-pound battery that will power the Chevrolet Volt on trips up to 40 miles. As a commodity, lithium currently costs about $2 a pound, probably not enough to warrant its recovery and reuse.

In the near term, many depleted electric car batteries will be processed by Toxco, a California-based division of the Kin*****ursky Brothers. Established in 1984, Toxco is a leader in battery recycling with facilities in California, Ohio, Tennessee and British Columbia.

The procedure currently used to recycle lithium-ion batteries at Toxco’s facility in Trail, British Columbia, begins with a deep freeze to minus 325 degrees Fahrenheit to stop the chemical and electrical activity. After shearing and shredding, the metals, plastics and chemical compounds are separated for sale or disposal. A chemical reaction converts the lithium to lithium carbonate, which has multiple uses in medicine, as an industrial chemical and to give fireworks and flares their brilliant red glow.

Last year, the Energy Department awarded Toxco $9.5 million to expand its Lancaster, Ohio, operations — currently used to recycle nickel-cadmium, nickel-metal-hydride and lead-acid batteries — to handle the expected influx of depleted lithium-ion batteries.

But lithium batteries are not all doomed to a fate of dismemberment: electric car builders and battery makers say that when a battery pack is no longer able to provide full performance or driving range and a replacement is deemed necessary, three-quarters of its energy capacity remains.

That is why, in the longer term, electric utilities may be the answer to where electric car batteries will be put out to pasture.

One of the most daunting tasks faced by utilities is to coordinate the generation and supply of electricity with fluctuations of demand. Consumers come home from work and switch on big-screen televisions while dinner is in the oven. That behavior, repeated throughout the community, produces a spike in energy demand. Then, after the evening news, people tend to shut off their lights and appliances, and demand plummets. The net result is that power-plant efficiency suffers because generators are not operated at a steady output.

Utilities already depend on buffers to level out supply and demand, pumping water into storage towers and compressed air into underground reservoirs as ways to manage generator usage. But with increased use of renewable — but fickle — energy sources like wind and solar, there’s a growing need for storage devices that are not a blight on the landscape.

“We’ve been watching electric car development for more than a decade,” said Mike Rowand, a technology adviser to Duke Energy of North Carolina. “The early batteries weren’t that attractive, but we jumped in full-force three years ago because so many automakers were involved.”

Southern California Edison has been promoting automobile electrification for two decades.

“We’re expecting electric vehicles to benefit not only the environment, but also to help the electric system work more effectively by absorbing some of the power produced in off-peak periods by wind generators,” said Ted Craver Jr., chief executive of the utility’s parent, Edison International. Mr. Craver said that his company operated the nation’s largest fleet of electric vehicles, which had traveled over 18 million miles in the last 20 years.

“We’ve built what we call the garage of the future featuring roof-mounted solar panels, a SmartConnect electricity meter and storage batteries,” he said. “Second-life batteries — those removed from road service — would be ideal for this application.”

Paul De Martini, vice president for advanced technology at Southern California Edison, said that 16 percent of the energy the utility delivered to customers already came from renewable sources — wind, solar and hydroelectric.

“This year, at one of our substations in the

Tehachapi Mountains where S.C.E. has numerous wind farms, we’re creating a utility-scale installation with 32-megawatt-hours of storage capacity in an 8,000-square-foot building,” he said. “The lithium-ion batteries supplied by A123 will fill in the peaks and valleys of the power produced by the wind generators.

Mr. De Martini added: “We expect the second-life batteries to become available around 2025. That gives us ample time to develop new battery-management systems suited to our specific application. One designed by Tesla is already under test.”

No one can say exactly how long lithium-ion batteries will last on the road or whether those removed from cars will compete favorably against next-generation batteries in the hoped-for utilities applications.

But there is a lot of optimism: General Motors has said it believes that post-auto uses will extend battery life by five to 10 years. Nissan has teamed with the Sumitomo Corporation to foster a second life for lithium-ion batteries removed from Nissan Leaf electric cars in a program called Reuse, Resell, Refabricate and Recycle. Custom repackaging to suit client needs is part of this business plan.