GM Defense Adapts Hummer EV for Military Concept Vehicle
The eMCV employs the roadgoing vehicle’s electric propulsion system and chassis, with some modifications.
GM Defense announced in July 2022 that the U.S. Army selected it to provide a battery-electric vehicle for analysis and demonstration. As a subsidiary of General Motors, that vehicle could be based on none other than the GMC Hummer EV pickup, production of which had just begun months before.
Less than a year after that announcement, GM Defense in June 2023 revealed at the Modern Day Marine Expo in Washington, D.C. its Electric Military Concept Vehicle (eMCV). Featuring GM’s Ultium Platform, the EV propulsion architecture satisfied the U.S. Army’s requirement for a light- to heavy-duty BEV that helps to reduce fossil-fuel reliance in operational and garrison environments.
“With access to GM’s advanced technologies, GM Defense is able to provide proven commercial technologies adapted to meet specific defense requirements and the needs of our customers,” said Steve duMont, president of GM Defense, which leverages GM’s $35-billion investments in EV and autonomous-vehicle technology. “This demonstration will prove to our U.S. Army customer…how the underlying technology can be leveraged for future defense needs, whether on an installation or in a tactical environment.”
The six-passenger eMCV uses the production Hummer EV’s chassis and suspension system, but with some modifications. GM Defense added 37-inch tires (compared to 35-inch for the roadgoing model), a new heavy-duty brake system and Fox performance shock absorbers. Engineers reportedly also improved upon the production truck’s already-impressive approach (49.7 deg.) and departure (38.4 deg.) angles to further enhance off-road performance.
The military EV adds a 46-inch gun ring, swing side-arm mounts and Silent Watch and Silent Drive capabilities, emitting low acoustic and thermal signatures. The concept also offers exportable power for mission-critical equipment. An onboard 12-kW diesel-powered generator provides limited battery charging and propulsion.
As in the Hummer EV Edition 1 truck, the eMCV’s Ultium battery pack consists of two layers of vertical cell modules, combined to form a 200+ kWh, 24-module pack. Mounted low in the center of the vehicle platform, the pack’s placement helps to keep the center of gravity low and enables short front and rear overhangs (34.7 inches/881 mm front, 46.5 inches/1,181 mm rear for the production model).
The three-motor e4WD propulsion system also is carried over from the Edition 1 model. The dual-motor rear drive unit features virtual locking capability; there’s a single motor and electronic locking differential up front. The resulting performance figures: 1,000 hp (745 kW) and 11,500 lb-ft (15,591 Nm) of wheel torque.
The eMCV is capable of 800-volt DC fast-charging up to 350 kW, enabling up to nearly 100 miles (160 km) of driving range in about 12 minutes. The military vehicle offers 329 miles (529 km) of combined driving range, according to GM Defense, with 0-60 mph (0-97 km/h) acceleration times as quick as 3 seconds.
Leveraging commercial technology
The eMCV is not GM Defense’s first go at an electric military vehicle. The company debuted its All-Electric Military Concept Vehicle (eISV) variant in 2021, which like the turbodiesel-powered ISV (Infantry Squad Vehicle), is derived from the Chevrolet Colorado ZR2 platform.
Based on the nine-passenger ISV, the eISV can carry five passengers and features GM’s commercially-available battery drive system and components. The vehicle features a cargo box and a modified integrated Roll Over Protection System (ROPS) constructed from 4130 chromoly steel tubing. Engineers developed the eISV from concept to execution in 12 weeks, according to GM Defense.
The eISV features an eCrate 400V, 3-phase AC permanent-magnet motor. A high-voltage GM BEV2 lithium-ion battery has a capacity of 66 kWh. The battery technology enhances capability with low acoustic and thermal signatures and serves as an onboard, mobile generation power source for various mission equipment payload packages.
Capable of Level 1 and 2 AC charging, as well as Level 3 DC fast charging, the eISV features an open architecture and can be customized to meet customer requirements. Accessories can be added to enhance the vehicle’s capabilities, such as additional lethality, remote weapon systems, fixed pintle or swing-arm mounts for medium and heavy machine guns and grenade launchers.
The ISV is comprised of 90% commercial-off-the-shelf components, including 11 Colorado ZR2 off-road suspension and chassis upgrades from Chevrolet Performance. GM Defense says the eISV maintains key attributes of the ISV, including the utilization of GM’s existing global supply chain for commercial parts. The front axle, for example, is the Colorado ZR2’s Dana M190 with electronic locking differential, and the rear axle a Dana M220 with electronic locking differential.
The electric vehicle can cover distances “similar to” ICE-powered solutions, the company says, and maintains the ability to be rapidly deployable. Weighing less than 5,000 pounds (2,232 kg), it can be deployed or inserted through C-17, C-130 and A400M low-velocity air drop, internally transported in a CH/MH-47 Chinook, CH-53E Super Stallion, CH-53K King Stallion or sling-loaded under a UH-60 Blackhawk.