ThunderPack II

The ISE ThunderPack represents the best available high energy storage system currently on the market. For electric and hybrid-electric applications, where maximum energy recapture and durability are needed in a small package the ThunderPack offers the best choice today.

Ultracapacitors are a new type of energy storage device that can be used in electric and hybrid-electric vehicles, either to replace or to supplement conventional chemical batteries. Ultracapacitors can store and release large amounts of power very rapidly, making them ideal for absorbing the electrical energy produced by electric and hybrid-electric vehicles during regenerative braking. In this process, the vehicle is slowed down by the main drive motor, which converts the vehicle's kinetic energy to electrical energy that can be stored by the ultracapacitors. When the vehicle needs this stored energy for acceleration or other power needs, it is released by the ultracapacitors almost instantly. This process can recapture up to 25% of the electrical energy used by such vehicles.

In addition to offering weight and volume reductions, ultracapacitors can last significantly longer than batteries. The Maxwell ultracapacitors in the ThunderPack system are designed for hundreds of thousands of energy storage-release cycles, versus rated lifetimes of 500 to 1,000 cycles for most chemical batteries. The ThunderPack system equalizes the charge levels of the 144 individual ultracapacitors in the pack, and is electronically linked by a J1939 CANbus to the vehicle control system to optimize overall vehicle energy management.

The ThunderPack offers several optional features, which include Reverse Polarity Protect (RPP), a "Safe on Disconnect" integrated contactor, and an integrated precharge circuit to match battery pack and ThunderPack voltages. ThunderPack is also thermally controlled to keep the ultracapacitors within an optimal temperature range. A single pack can store and release more than 150 kW and a dual pack rated at 300 kW can meet the most demanding acceleration and peak power needs of large transit buses and trucks.

ThunderPack can also be used to handle fluctuating power demands in stationary distributed power systems, helping to stabilize electrical loads on the principal power generation source or grid. ISE offers a variety of ThunderPack sizes and configurations for both vehicle and stationary power applications.