Electric avenue: QinetiQ on battlefield electrification

QinetiQ’s business development lead for power sources, energy storage & energy distribution Victoria Doherty discusses advances in hybrid electric systems for military vehicles with Harry Lye.

QinetiQ's work in battlespace electrification spans a number of technology areas, from energy storage systems and cell development to independent test and evaluation of new technologies and near-commercial materials to explore their benefits and limitations for specific defence applications. The company also works on regulatory and hazard testing of new products to defence standards to qualify them for the field.

Harry Lye:

Can you give us some examples of  QinetiQ's work in the field of battlespace electrification?

Victoria Doherty:

QinetiQ is supporting advancements in the field of battlespace electrification in several ways, from accelerating the adoption and prototyping of disruptive technologies, to driving strong, collaborative and commercially innovative partnerships.

QinetiQ is working closely with leading universities, the government’s Faraday initiatives and emerging SMEs to assist with development and scale-up of new technologies to accelerate advances in this area and to evaluate their potential for existing and future military applications.

One example of this is the Faraday funded SUPErB programme that is being led by QinetiQ and is developing a new type of very high power cell that can be charged as quickly as it can be discharged and which offers better safety than commercial lithium-ion technology. This type of cell offers significant improvements in performance for hybrid electric military vehicles as well as enabling new applications such as directed energy systems.

QinetiQ is involved in programmes to develop new commercial products that will offer benefits for military use. For example, QinetiQ is working with Deregallera, a company based in Caerphilly that is developing sodium-ion battery materials. Sodium-ion cells will be substantially lower cost than lithium-ion and they are safe to transport by air as they can be completely discharged, unlike lithium-ion.

Sodium-ion has lower energy density so these batteries are ideally suited to grid or military infrastructure applications such as forward operating bases, and to contribute towards the MOD’s drive to reduce its carbon footprint.

What can you tell us about your work with BAE Systems on a hybrid drive Bradley IFV?

The Bradley demonstrator programme represents an important milestone in the journey towards tracked combat vehicle electrification, not only for the US DoD and BAE Systems, but also for QinetiQ as creator of the E-X-Drive – an electro mechanical transmission for tracked platforms currently validated to TRL 7 through customer and QinetiQ funding. The programme is also an excellent example of rapid creation in response to RCCTO’s requirements for the hybrid Bradley demonstrator.

The new modular E-X-Drive (M-EXD) concept will be developed, integrated and tested in the Bradley to demonstrate the potential capability and operational benefits of a hybrid electric drive powertrain in comparison with the conventional mechanical. Modularity and scalability are at the heart of QinetiQ’s M-EXD design and the technology can be easily adapted to suit requirements across the range of tracked vehicle applications.

And beyond this specific customer requirement there is a broader opportunity: how to exploit the UK’s unique military hybrid electric drive sub systems to create new opportunities for multinational capability collaboration.

Hybrid vehicles have existed for a long time in the commercial sector. What has prevented adoption in defence so far?

Military armoured vehicle acquisition cycles are much longer and potentially more complex than the commercial vehicle market. Until recently there has been a degree of unfamiliarity with high voltage electric drive which may have caused concerns; however, in recent years the widespread adoption of the technology in the civil sector, as well as a cultural shift, seems to have made these concerns less acute.

This has led to large investment in, and subsequent development of, supporting and component technologies that can be leveraged and applied to the military solution, accelerating the adoption of disruptive technologies.

It is important to note that the performance requirements in the commercial market are very different to the military and although component technologies can be leveraged, the commercial markets have not, and will probably not, deliver armoured fighting vehicle transmissions. Lastly, the need for increased electrical power in the modern-day battle space is more acute than ever and electric drive is recognised as a must have to maintain and improve capability.

A recent US Army report found that battery size is preventing military vehicles from going fully electric. How soon will we see batteries powerful enough to run a tank that are also small enough to fit in one?

The energy density of batteries, particularly lithium-ion types, has increased substantially since their commercial introduction in 1991 from 150 Wh/kg to around 270 Wh/kg and 700 Wh/L today. These improvements have come about through improved engineering and production methods and through improvements in the capacities of the active components; the anode and cathode electrodes.

Modern cathode materials are complex, multi-metal oxides that have 30% more capacity than those used in the first cells, but ongoing capacity improvements are more evolutionary than revolutionary. The anode has remained largely unchanged since lithium-ion’s introduction and is a graphite material. Use of graphite poses some limitations on the battery; slow charging and limited temperature range being key operational ones.

More recent developments have introduced other anode materials, for example silicon and tin, that offer ten times higher capacities and metal oxides, such as lithium titanate, which provide high power capability. These materials are being introduced into commercial cells as the technologies mature and will enable further improvements in energy density.

Among the battery technologies currently in development, a combination of two advances, lithium metal anodes and solid-state batteries, offers a step-change in energy density. Use of lithium anode pre-dates lithium-ion but safety issues and short cycle-life prevented commercialisation; however, it offers the highest energy density compared to other anode materials.

Solid-state batteries use a thin layer of material to replace two cell components (separator and electrolyte) and this substantially improves energy density whilst reducing safety issues. It also enables use of lithium anodes. Cells delivering over 400 Wh/kg have been reported recently with the principal challenges now being production and cost reduction.

What lines of development is QinetiQ working on for dismounted personnel?

In the UK, QinetiQ is supporting the dismounted close combat (DCC) domain with test and evaluation and engineering advice ranging from soldier lethality and C4I to training programmes in support of major land experimentation events.

One of our current key DCC projects is working for Army Headquarters in delivery of TommyWorks. TommyWorks is focused on integration of dismounted soldier equipment in a coherent manner to deliver an integrated soldier system. QinetiQ, supported by our partners in the Aurora Engineering Partnership, is assisting Army Headquarters to manage the integration and evaluation of a range of new or updated equipment which will be fielded with the UK Enhanced Light Force Battalion (ELFB).

This work spans all defence lines of development and the QinetiQ team are working closely with Army Headquarters and the Infantry Trials and Development Unit to support the roll-out of equipment to the ELFB. This will allow the unit to incorporate these new capabilities into their training cycle and for the benefits to be measured against baseline performance.

The TommyWorks process will allow Army Headquarters to manage integration of individual items of equipment and help drive a cycle of continuous improvement to dismounted forces.