No Fire Here: The Power of Lithium-Ion Batteries

Lithium-ion batteries are the most common kind of battery found in fully electric vehicle  and for good reason – they have some of the best energy density(energy per square inch of battery) and only a slow loss of charge when not in use. They’re in your cell phones, laptops, and now in your cars, but many consumers don’t understand how a rechargeable battery works.

In this brief article, we’ll explain how a lithium-ion battery works and some of the cool scientific discoveries around this amazing kind of battery.

Batteries and the Electric Car

For the longest time, the limiting factor in electric car deployment was the battery. Storing energy is difficult and has only recently caught up to the power demands we have of technology.

Internal combustion engines are really good at creating energy through combustion. The small amount of electricity needed to light the spark was negligible on an electric battery – and let’s be honest, we all run our battery out leaving the lights on! Although batteries existed in the 1970s, the range for powering a car was less than 50 miles – not nearly enough to compete in any serious fashion with the electric car.

Enter the lithium-ion battery – small and compacy, powerful and quickly charged, and not one to discharge easily. Now we’ve got a game changer in the fully electric vehicle market!

Rechargeable and Reusable

Remember how electricity works  – passing electrons along atoms to generate energy? A battery uses the same principle by storing electrons on atoms inside a cell.

Most batteries work using a chemical reaction – electrical energy is converted from two compounds mixing together at a very controlled rate. A battery has at least two half-cells – an anode (where the elctrons start) and a cathode (where the electrons end up). The chemical reaction forces the electrons from the anode to the cathode across a bridge.

In a lithium-ion battery, the chemical reaction happens in a gel polymer that holds a substance that’s rich with lithium ions (if you want to know the name of the electrolytes, take a look at this Wikipedia article). When you activate the battery, the lithium ions move from the anode to the cathode, letting go of their electrons, which create electricity!

How a lithium-ion battery discharges and powers your devices. Image from HowStuffWorks

To recharge, the battery moves the lithium ions back to the anode through another chemical reaction.

Lithium-ion batteries are very good for portable devices, like cell phones, laptops, and cameras. It’s estimated that nearly 70% of the rechargeable electronics produced in Japan are made with lithium-ion batteries

Advancements in Battery Technology

We posted recently about a 3D lithium-ion battery model out of the University of Illinois Urbana-Champaign. Instead of using a 2D model of diffusion, the reseachers’ batteries are in a 3D skeleton of styrafoam. This allows for more surface area for the chemical reaction to occur, meaning that batteries hold more power and charge siginificantly faster than current models.

There has also been research into making a solid-state lithium ion battery. Currently, lithium is stored as a liquid in batteries because of how easily it moves around the half-cell. Researchers, however, have begun experiments with lithium in solid form, meaning that we can draw as much as 95% of the battery’s potential power when in use, a significant improvement over the status quo.

Fancy physics and chemistry aside, the lithium-ion battery is one powerful piece of technology.

Advertisements

Electric Car Controllers: Not Just For Video Games

People say controller and you may think of a few things: the device with buttons you use to play video games, the woman that directs air traffic, or (in rare cases) the person who supervises the financial and accounting activities of a business.

We’re thinking of the electric car controller, and here’s why you should think about it too!

On a large-scale, electric car engines aren’t very difficult and have three central components. There is a battery, responsible for operating all functions of the car, a motor that powers the car. The third, a piece missing from gasoline powered engines, is the controller.

Pedal to the Metal

The controller’s job is to interface the battery with the motor and control the amount of electrical energy that the car is using.

motor-img

Diagram of how a DC motor and controller system function in an electric car. Diagram created by Yiran, based on a diagram from How Stuff Works

When you push the pedal down on a gasoline engine, you allow more or less gasoline into the system to accelerate the car. An electric car’s pedal works the same way, except that the pedal doesn’t connect directly to the battery (to do that would be very inefficient).

The pedal connects to a device called the potentiometer, which converts the pressure into digital information. That data gets passed to the controller, where it turns the data into specific commands on how much battery power to drain and give to the motor.

The controller also regulates how much power can go into the motor at once, avoiding unnecessary burnout and complications caused with a malfunctioning motor.

You can think of the controller in an electric vehicle much like you think of the air traffic controller at an airport. His goal is to ensure that too much traffic does not surge through the system, causing delays and avoiding accidents between planes. A controller works in much the same way, regulating the flow of information the driver provides into a manageable stream of electricity to power the car.

Presentation Tomorrow on Our Research!

Tomorrow, the members of Shifting Currents will present the results of our research to the CCT 506 class. We will be describing how the modern electric car works, its history, and the implications of the adoption of the electric car. Wish us luck!

New Lithium-ion battery in development, what does this mean for electric cars?

Researchers at the University of Illinois at Urbana-Champaign have developed a lithium-ion battery that recharges 1000 times faster and is 2000 times more powerful than other lithium-ion batteries on the market. From ExtremeTech on Wednesday:

According to the researchers, this is not simply an evolutionary step in battery tech, “It’s a new enabling technology… it breaks the normal paradigms of energy sources. It’s allowing us to do different, new things.”

Combining both power and longevity in a light battery is something engineers have been trying to solve for decades. You can either have a very powerful battery that discharges a lot of power for a few seconds or a battery that provides a low source of power for an extended period of time. The lithium-ion battery that is commonplace in cell phones, laptops, and electric cars  is the best balance scientists have developed thus far that balances these two concerns.

A technical diagram of how a lithium-ion battery works and how the new 3D structure of the battery developed at UI Urbana-Champaign will function. Image from ExtremeTech

Normal lithium-ion batteries are 2-dimensional structures that use lithium ions to move electrons around. A chemical reaction occurs in the battery, making the lithium ions act as sponges for electrons that allow electricity to flow easily through.

This new technology developed at UI creates 3-dimensional structures made of Styrofoam and nickel that allow for more suface area for these chemical reactions. In essence, the researchers have found a new material for the sponge and have made it thicker so that electrons can pass more quickly around the battery. This new technology allows for very rapid charging times and more power to be held by the battery.

This new form of battery has only been developped as a button-sized battery, but the potential implications of a battery with such significant improvements is obvious. Electric cars run entirely off of batteries and the two major downsides to them are the range and the charging time. If technological developments could even improve charging time and range by 5x their current value, it is likely that the electric car would be adopted with less hesitancy than it is now.

Tell us: should we be excited about this development for the future of the electric car?

Full article link: “New lithium-ion battery design that’s 2,000 times more powerful, recharges 1,000 times faster” on ExtremeTech, URL : http://www.extremetech.com/computing/153614-new-lithium-ion-battery-design-thats-2000-times-more-powerful-recharges-1000-times-faster

Chatting with an Electric Car Owner Today – Tweet Us Your Questions!

We are speaking with an electric car owner and representative of the American Association of Motor Vehicle Administrators. Please tweet us any questions you may have at @shiftincurrents!

Fisker Automotive Lays Off Employees, Draws Criticism

Not all of the stories regarding electric car manufacturers sing as sweetly as Tesla, BMW, or Nissan.

Fisker’s first car design, the Karma, at a Geneva auto show in March 2013

From the NY Times:

Fisker Automotive, the maker of a $100,000-and-up plug-in hybrid luxury sedan, said on Friday that about three-quarters of its workers had been let go to “allow the company to work through its current financial challenges.”

As one of the competitors in the luxury electric car market, Fisker’s cars are sleek and styled elegantly. But that styling was not enough to overcome financial hardships caused by low sales, production problems and a major recall, and the devastating effects of Hurricane Sandy.

Although Fisker successfully brought its stylish Karma sedan to market in late 2011, the company has had a spate of problems in recent months, including a recall of more than 2,000 cars to replace a cooling fan. Last October, 320 Karmas, awaiting delivery to customers, were destroyed by Hurricane Sandy at Port Newark in New Jersey, resulting in a $32 million loss for the automaker.

One of the stresses of innovative technologies is that, while some companies do well and have visible and positive press, many others will fail. Fisker’s massive layoffs and corporate restructuring indicate that it could be one of such ventures that fails. Critics have pointed at the loans offered to Fisker by the Department of Energy in 2009 as a failing of the US government to adequetely predict the success of a company’s output. Others have replied that, while it is a shame that some loans will never be paid back because the innovation is not successful, these kind of loans are necessary to spur companies to develop new and creative technologies, electric cars being one of them.

Do you think the government should take “chances” on innovative technologies, like electric cars, realizing that some will fail? Is investment in electric car technology something that the US government should invest in?

Full Article link here: http://wheels.blogs.nytimes.com/2013/04/05/fisker-automotive-lays-off-majority-of-employees/?ref=electricvehicles

Come Meet Us on 4/18

Shifting Currents will be presenting some of our research findings at a poster session on Thursday, April 18 from 4-6pm in the CCT Lounge. We will be there with the rest of the students conducting investigations of other technology, but make sure to stop by our poster to learn more about our awesome project!

How Does The Motor of an Electric Car Work? A Poster

Shifting Currents has created another awesome piece of material for you to learn about the electric car – a poster describing how the engine and motor function, as well a brief overview of the history of EVs. Download the full version by clicking on the image below:

poster_final

Our group will be attending a poster session this week to present to the community at Georgetown how electric cars work. Wish us luck!

History of the Electric Car: A Timeline

Our team has put together a printable timeline of the history of the fully electric vehicle, starting with the

The fully electric car has three rises in popularity: its original inception in the early 1900s, renewed interest in the 1970s due to the energy crisis, and modern day electric cars with household names such as BMW, Nissan, and Tesla.

Feel free to download, print, and use this information for learning and teaching others about electric cars!

Download the full PDF version here (428Kb)

Fascinating National Geographic Video: Building the Tesla Motors Factory

Check out this National Geographic video showing the process behind the
construction and assembly of the Tesla Motors factory in Silicon Valley, “a
factory like no other.” The factory is highly significant because it is “the world’s
first manufacturing plant for the fully electric car.” See where Tesla cars are
produced, what the machinery and automated production line look like, and how
factory workers get to ride bikes around the factory!

Watch and enjoy: http://natgeotv.com/ca/megafactories/videos/brand-new-tesla-factory