Hyliion Launches Improved Hybrid Truck Powertrain, All-Electric HyperTruck ERX
Hyliion announced an improved version of its Hybrid system at the Advanced Clean Transportation Expo in Long Beach, California, and showed off a long-range version of its Hypertruck ERX that will help truck makers meet California zero-emissions truck regulations.

Werner Enterprises is a new Hyliion customer, showing off a truck with the new Hybrid eX powertrain at ACT Expo.
Photo: Jack Roberts

Hyliion's new Hypertruck ERX on display at ACT Expo.
Photo: Jack Roberts
Hyliion announced an improved version of its Hybrid system at the Advanced Clean Transportation Expo in Long Beach, California, and showed off a long-range version of its Hypertruck ERX that will help truck makers meet California zero-emissions truck regulations.
This updated version of Hyliion’s hybrid powertrain, designated the Hyliion Hybrid eX, offers fleets a lighter solution that is easier to install, service, and operate, according to the company. The Hybrid eX draws upon the real-world feedback Hyliion has received from customers and the millions of miles logged with the previous system.
The Hybrid eX features a number of improvements over the earlier Hybrid configuration, including:
A simpler, more rugged design with a consolidated battery box that aims to significantly streamline the installation process
Reduced net system weight, allowing for greater payload
New e-axle for improved efficiency
Refined software and cloud connectivity aiming to deliver over-the-air performance and proprietary updates more efficiently
New automatic traction-assist feature and updated control interfaces for improved driver experience.
Cybersecurity advancements
“The launch of the enhanced version of our Hybrid powertrain is a major milestone in our Hybrid commercialization process and reflects the ongoing work we are doing to innovate for the benefit of commercial fleets and the environment,” said Thomas Healy, founder and CEO of Hyliion. “We expect these improvements to make the Hybrid that much easier for fleets to adopt, while also helping them to achieve their ESG and emissions targets.”
Hyliion expects to begin shipping Hybrid eX units in the latter part of 2021. Initial recipients include both returning Hyliion customers, and new customers such as Werner Enterprises, whose truck was featured in Hyliion’s booth at the ACT Expo.
Hyliion’s Hybrid solution is designed for Class 8 diesel and compressed-natural-gas commercial trucks, providing fuel savings, performance and other improvements via an energy regeneration powered electric hybrid system, depending on truck configuration and fuel type. Combined with Hyliion’s proprietary software and battery technology, this comprehensive solution also contains an integrated auxiliary power unit (APU) to reduce idling.
Hypertruck ERX
Hyliion also showed off an all-electric Hypertruck ERX validation unit at ACT Expo.
The Hypertruck ERX was first announced in the summer of 2020. In late July, Hyliion announced a long-range variant of the Hypertruck ERX, which will be the first version brought to market and was the one on display in Long Beach.
The Hypertruck ERX will offer more than 1,000 miles of total range, according to the company, enabling freight hauling capabilities comparable to diesel. The electric powertrain system uses an onboard generator to continually recharge the battery pack while driving, eliminating the range and charging infrastructure challenges that battery-only electric trucks now face. The Hypertruck ERX is also plug-in capable, allowing fleets the operational flexibility to recharge with low-cost renewable electricity from the grid.

Thomas Healy, founder of Hyliion, speaks at ACT Expo with the new Hypertruck ERX behind him.
Photo: Jack Roberts
This enhanced option, which will offer 75 miles of all-electric range, will enable Hypertruck ERX equipped production trucks to qualify for zero-emission vehicle credits by meeting California’s Advanced Clean Truck (ACT) Rule.
Hyliion is collaborating with major truck manufacturers to offer the long-range iteration of the Hypertruck ERX. Taking a modular approach to the platform to meet OEM demand, address fleet needs and satisfy government mandates, the production Hypertruck ERX will be available in multiple iterations, including a reduced electric-range model that will follow the release of the long-range version.
A picture is worth a thousand words... but a video is so much more. pic.twitter.com/NPqyTphGpS
— Hyliion (@hyliion) August 23, 2021
The ACT rule, approved by the California Air Resources Board in June 2020, requires Class 8 truck tractor manufacturers to sell zero-emissions vehicles in California, beginning with model year 2024. The sale of a battery or fuel cell vehicle earns one credit towards an OEM’s ACT obligation. Based on this rule, truck manufacturers will be able to achieve up to a 75% ZEV sales credit by selling a Class 8 truck with the Hypertruck ERX electric powertrain, according to Hyliion.
While California was the first state to introduce a ZEV sales requirement for medium- and heavy-duty trucks, both New Jersey and Washington have initiated formal regulatory processes to adopt the ACT Rule. Massachusetts, Rhode Island, New York, and Connecticut have also considered adoption of California’s ACT regulation.
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