Assessing GM's Fuel Cell Strategy

http://www.technologyreview.com/read_article.aspx?id=17586&ch=energy

By Kevin Bullis

The automaker plans to begin rolling out a test fleet of fuel-cell cars, but some experts say it's a mistake.

Friday, October 06, 2006

BMW's Hydrogen Hopes

http://www.technologyreview.com/read_article.aspx?id=17526&ch=energy

By David Talbot

Hydrogen may never be feasible as a fuel for vehicles, but BMW is pushing ahead anyway with an advanced hydrogen-gas combustion hybrid.

The internal combustion engine in BMW’s new hydrogen-gasoline hybrid engine can switch seamlessly between the two fuels. And control systems optimize the concentrations of hydrogen being burned, which can minimize or eliminate one of the downsides of hydrogen combustion: the formation of nitrogen oxides. While BMW hopes its new model will help drive the adoption of hydrogen in vehicles, experts are skeptical. (Credit: BMW)

Friday, September 22, 2006

Lithium Ion Hybrid Batteries

http://www.hybridcars.com/lithium-ion-hybrid-batteries.html

A Laptop in Every Garage
The emergence of small lightweight long-running lithium-ion batteries has helped create a market for notebook computers, cell phones, and other portable devices from the iPod to the BlackBerry. Now, efforts to scale that technology for use in car batteries could do for the automotive industry what it did for computer and phone companies. The benefit for consumers could be revolutionary: hybrid or pure electric cars with great efficiency, acceleration and range—at the same price or cheaper than today's conventional cars.

Ultracapacitors & Hybrid Electric Vehicles

http://maxwell.com/ultracapacitors/applications/transportation.html

Application: Hybrid Electric Vehicles (HEV)

Key Customer Requirements

Manufacturers of HEV's are looking at relieving battery's load during high power times, such as initial acceleration and braking. These are the instances when the batteries see the highest current levels. By load leveling these spikes the batteries will last longer, saving the customer money.

Maxwell Solution

Maxwell Technologies ultracapacitors were designed to work with system batteries to improve power management and relieve peak load times stress on batteries. Our ultracapacitor technology protects the battery. It allows the battery to handle the energy requirements while the caps handle the high power requirements.

Customer Benefits

Ultracapacitors significantly improved power management in the hybrid electric vehicles and extended battery life. In addition, ultracapacitors allow for lower emissions, better fuel-efficiency and advanced electrical drive capabilities. The new power system using ultracapacitors allowed the HEV to recapture and reuse braking energy. Compared to conventional diesel engines: reduction of fuel consumption was estimated at greater than 50%; reduction in particulate emissions was greater than 90%; and reduction of nitrogen oxide emissions was 50%.

ISE Corporation - Hybrid Electric Vehicle

http://maxwell.com/ultracapacitors/applications/ise.html

ISE Corporation Case Study

The depletion of natural resources, air pollution and the rocketing price of gas are all issues that impact the automotive industry. Fortunately, something is being done about it. “Transportation for a clean planet” is the motto of the ISE Corporation, which has been building hybrid and electric vehicles since 1996.

The Problem

ISE's Hybrid Electric Vehicle (HEV) technology combines the best characteristics of fuel-driven engines, electric motor drives and energy storage components. Their solution has been designed with a combustion engine that functions as the primary power source, and an electric motor with a power storage system that functions as the secondary power source. Designers are able to size the combustion engine for cruising power requirements thanks to the presence of the secondary power source that handles the peak power demands for acceleration. Additionally, regenerative braking energy is captured by the secondary power system and that energy is applied for further acceleration or for the basic energy needs of supplementary electrical systems by using the secondary source.

Using only batteries to provide the electrical power storage has drawbacks in the hybrid application. These deficiencies are multiple, and they create many design challenges for automotive engineers. Firstly, batteries have difficulty functioning in cold weather. Secondly, batteries require a sophisticated charge equalization management. Thirdly, batteries have limited cycle life under extreme conditions, which results in high cost replacement throughout the life of the vehicle. A new battery has to be purchased and installed; the old battery has to be removed and disposed. Battery disposal can be problematic unless the manufacturer has a recycling program. All of this adds to the cost of a battery-based system.

Perhaps most importantly though, batteries are limited in their ability to capture and provide bursts of high power during short duration events such as acceleration and regenerative braking. This high power limitation reduces the efficiency of the hybrid electric drive system design.

The Solution

ISE's solution to the above stated problems has been to think beyond batteries; to the reliable technology of ultracapacitors. An ultracapacitor can fulfill many of the functions of batteries in this application, but with dramatically higher reliability and overall performance.

Compared to batteries, the key benefits offered by BOOSTCAP ultracapacitors are as follows.

• Ultracapacitors function well in cold weather, down to –40° Celsius, whereas, without heating, batteries do not operate reliably below 0° degrees Celsius.
• Ultracapacitors are a safe solution as a pack with equalization is discharged over night.
• Ultracapacitors have a long life cycle, basically built to last the lifetime of the machine into which they are incorporated and as they are maintenance-free, that ultimately results in cost savings.
• Ultracapacitors are more efficient than batteries; 84-95% as compared to an average of below 70% for batteries in this application as measured by ISE.
• Ultracapacitors are very earth-friendly as they are 70% recyclable and do not include any heavy metals which are detrimental to the environment.
• Ultracapacitors offer up to 10x the power of batteries and in terms of acceleration of a vehicle, this plays an important role.

ISE Corporation - ThunderPack:

http://www.isecorp.com/ise_products_services/components_subsystems/ultracapacitor-packs.php

How an Ultracapacitor Works

http://www.nrel.gov/vehiclesandfuels/energystorage/ultracapacitors.html

Ultracapacitors

Like batteries, ultracapacitors are energy storage devices. They use electrolytes and configure various-sized cells into modules to meet the power, energy, and voltage requirements for a wide range of applications. But batteries store charges chemically, whereas ultracapacitors store them electrostatically. Currently, ultracapacitors are more expensive (per energy unit) than batteries. Ultracapacitors are true capacitors in that energy is stored via charge separation at the electrode-electrolyte interface, and they can withstand hundreds of thousands of charge/discharge cycles without degrading. They provide quick bursts of energy.

NREL – National Renewable Energy Laboratory

Advanced Vehicles and Fuels Research

Energy Storage

How a Battery Works

http://www.nrel.gov/vehiclesandfuels/energystorage/batteries.html

Batteries

A conventional vehicle uses a lead acid battery to start the engine and power auxillary loads (lighting, electronics, etc.). Hybrid electric, electric, and fuel cell vehicles (HEVs, EVs, and FCVs) have conventional lead acid batteries, but also have propulsion batteries, which are constructed quite differently—they are built for high power, high energy, and long cycle lives. Some low-voltage hybrid vehicles use advanced lead acid batteries, known as valve regulated lead acid (VRLA) batteries.

NREL – National Renewable Energy Laboratory

Advanced Vehicles and Fuels Research

Energy Storage

Plug-In Hybrids Are on the Way

http://www.technologyreview.com/read_article.aspx?id=16922&ch=biztech

By Kevin Bullis

Cars with advanced batteries get 100 mpg and boast far greater range than all-electric vehicles.

Wednesday, May 24, 2006

Better than Hybrids

http://www.technologyreview.com/read_article.aspx?id=16727&ch=biztech

By Kevin Bullis

A proposed engine design approaches the efficiency of gas-electric hybrids, but could be far cheaper.

Monday, April 24, 2006

The Lithium-Ion Car

http://www.technologyreview.com/BizTech/wtr_16624,295,p1.html

By Kevin Bullis

Altair Nanotechnologies plans to road test an advanced electric vehicle prototype.

Friday, March 24, 2006

Practical Fuel-Cell Vehicles

http://www.technologyreview.com/BizTech/wtr_16504,296,p1.html

By Kevin Bullis

Hybrid vehicles operating in an unusual environment are lifting the prospects of fuel cells.

Friday, March 03, 2006