The future of electrification for military vehicles

Here, Roger Brereton, Head of Sales at military steering systems manufacturer Pailton Engineering, takes a closer look at the new hybrid-electric JLTV (eJLTV) and asks what role hybrid-electric vehicles will play on the battlefields of the future.  

The Oshkosh JLTV is regarded by many as the military vehicle par excellence, having replaced the iconic Humvee. In comparison to its predecessor, the JLTV boasts far superior reliability, speed and blast protection. When the BBC’s Top Gear took it for a test drive, its reporter described it as ‘the best riding car I’ve ever driven’.

The eJLTV claims to offer the same performance levels as its diesel counterpart but with a 20% improvement in fuel economy. The vehicle’s lithium-ion battery charges while in use and can be fully charged in 30 minutes, providing approximately 30 minutes driving time. The hybrid technology offers the tactical advantage of silent drive, extended silent watch and increased exportable power for use in combat and reconnaissance scenarios.

In September 2022, Oshkosh will recompete for the $6.5bn contract from the US Army to continue production of the vehicle for the next five years. Although the Army has not requested hybrid vehicles, the launch of the eJLTV needs to be seen within this wider commercial context. Oshkosh will face stiff competition from powerhouses including AM General, GM Defense and Navistar. If the eJLTV can offer similar performance levels to its ICE equivalent, does this mean we can expect widespread uptake of hybrid electric military vehicles in the near future?

The challenges of electrification

Both the military and original equipment manufacturers (OEMs) have been developing and testing hybrid variants of their vehicles in recent years. For example, at a recent Army-sponsored technology day, GM Defence showcased an electrified version of its Infantry Squad Vehicle, which had been developed in just twelve weeks. However, in June 2021, a report sponsored by the deputy assistant secretary of the Army for research and technology cast doubt on the long-term viability of electric military vehicles, citing concerns about vehicle weight and the need for charging infrastructure as major obstacles. 

For a fully electric vehicle, the added weight from the battery would be much greater than a hybrid vehicle. Larger vehicles like the Medium Tactical Vehicle Replacement (MTVR) would require even larger batteries, so electrification is only really an option for smaller, lighter vehicles. Even with expected improvements in battery density in the coming years, it is unlikely to significantly offset the additional weight these vehicles will need to carry.

The challenge of recharging the vehicles is perhaps even greater. A fleet of electric vehicles would require a vast mobile charging system, which would hinder the Army’s ability to be mobile. Given these challenges, it is difficult to imagine electrification being feasible for the military sector for a very long time.

Is hybrid the happy medium?

Given the obstacles to adopting fully electric vehicles, hybrid technology has considerable appeal. As the battery can charge itself while the vehicle is in use, this solves the problem of needing charging infrastructure. Furthermore, although the hybrid vehicles will likely weigh more, these gains are not of the same magnitude as for fully electric vehicles. The eJLTV weighs an additional 453kg and although this is not insignificant, it is substantially less than the weight of a battery that would be required for a fully electric JLTV.

The tactical benefits of eliminating the noise and heat signatures associated with diesel engines include increased stealth. Added to this is the opportunity of using hybrid vehicles to export power to where it is most needed. The next generation of vehicles could potentially power an army field hospital or provide emergency power to relief teams in a disaster zone.

Most experts would be united in recognising that the challenges of introducing electric-hybrid technology to the military sector are greater than for commercial vehicles. Military vehicles must be purpose built and face greater challenges in comparison to commercial vehicles, from being shot at to enduring extreme temperatures and terrains. Everything from the steering parts to the windows need to be designed with this in mind. However, the unveiling of the eJLTV shows that hybrid-electric vehicles are becoming a more feasible option going forward, especially for lighter vehicles.