PowerCache Ultracapacitors (San Diego, CA), a part of Maxwell Technologies' (San Diego, CA) electric components group, announced that ISE Research-ThunderVolt Inc. (ISE-TVI, San Diego, CA) has completed development and manufacturing of ThunderPack, an electronically controlled ultracapacitor pack that uses PowerCache's PC2500 ultracapacitors. The energy storage device, which consists of 149 PC2500s, was delivered to the University of Nevada, Las Vegas for use in an experimental hybrid-electric transit bus.
ThunderPack works by using the PC2500's ability to capture regenerative energy. As the vehicle is slowed down by the main drive motor, its kinetic energy is converted into electrical energy that can be stored by the ultracapacitors in the pack. This process can recapture up to 25 percent of the electrical energy used by such vehicles.
ThunderPack employs an integrated system to equalize and individually monitor the charge level of the 149 PC2500s in the pack. It is electronically linked by a J1939 CANbus to the vehicle control system to optimize overall vehicle energy management.
ThunderPack also offers safety features that include reverse polarity protect, a safe-on-disconnect integrated contactor, and an integrated pre-charge circuit to match battery pack and ThunderPack voltages. The units are thermally controlled to keep the PC2500s within an optimal temperature range. A single pack can store and release more than 150kW and a dual pack, rated at 300kW, can be used to meet the needs of large transit buses and trucks. In addition, ISE-TVI claims that ThunderPack can be used to stabilize electrical loads on the principal power generation source in stationary distributed power systems.
ISE-TVI offers a variety of ThunderPack sizes and configurations for both vehicle and stationary power applications.