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