Power to Defend: Producing the Next Generation of Military Batteries

On the battlefield, there is no room for cutting corners when it comes to reliability, safety, and accuracy. Weapon systems and military vehicles are required to meet the strictest standards of production and operational quality. Often, these systems must withstand harsh weather conditions and meet complex operational requirements. The batteries in attack drones, APCs, and military communication devices must be able to withstand great pressures and challenges, much more so than equivalent civilian products.

In recent years, there has been a revolution in military products. Alongside old mechanics, electronic and computer systems are coming into use in military equipment on an unprecedented scale. The small communication devices held by the soldier in the field, tanks, drones, missiles, and satellites flying in space, all these modern weapon systems consume considerable amounts of electrical energy.

Development of tactical batteries
The change in the way modern weapon systems are developed raises difficult challenges. The energy that the weapon systems consume must come from reliable and safe sources that can function under the most difficult and challenging conditions in the field. The batteries of tanks and communication devices are supposed to work uninterruptedly in unusual environments and under harsh conditions and increased stress.

Additionally, accumulators and batteries are exposed to the risk of being damaged on the battlefield. Because of exposure to high temperatures or as a result of a direct hit, there is serious risk involved in any scenario of a battery igniting inside a weapon system. Therefore, the same demand for uncompromising quality that applies to all weapon systems is present manyfold in the sensitive energy components.

This is where the Israeli company Epsilor comes into the picture. Epsilor develops accumulators and batteries for security and military needs. It places great emphasis on battery safety and compliance with extreme environmental conditions. The company has offices in Beit Shemesh and a production line in Rotem Industrial Park in Dimona. Currently, it employs about two hundred workers, including some sixty engineers. Epsilor Electric Fuel is the result of a merger between the old Epsilor and Electric Fuel.

Electric Fuel, established in the early 1990s, dealt with zinc-air cell technology and began its journey by developing zinc-air batteries for the automotive industry. At the beginning of the 2000s, Electric Fuel moved into the defense sector and acquired Epsilor, which since its founding has been involved in the development of tactical batteries for the Ministry of Defense, mainly for night vision and communication devices.

For the past twenty years, Epsilor-Electric Fuel has positioned itself as a leading player in the field of military batteries and accumulators. After the merger, Epsilor began to expand into larger military batteries. Today the company serves customers in Israel and around the world. Beyond the fields of security, Epsilor develops batteries and accumulators for medical and communication needs as well as for civil aviation.

"We at Epsilor offer a wide variety of products in the field of accumulators and batteries," explains Ori Kost, Development Manager at Epsilor. Kost started working for Epsilor about 11 years ago, and today he leads the development of large batteries and complex energy systems. "From our point of view, tactical batteries are divided into three types: standard batteries for systems like communication or electro-optical devices; batteries developed specifically for the needs of drones and gliders; and 6T batteries that operate according to a strict global standard."

The next generation of military batteries
Last year, at the Eurosatory exhibition in Paris, Epsilor unveiled its Li-ion 6T battery system—the next generation of military batteries. 6T type batteries are intended for military vehicles such as tanks, APCs, and other armored vehicles. "This is a battery similar to the one found in a private car as far as size is concerned, but completely different from the point of view of technology," says Kost. "The batteries were designed to meet the strict requirements of the US Army and NATO."

The world of batteries for military vehicles is considered particularly complex and challenging. These accumulators are designed to provide greater energy relative to the same battery volume to armored fighting vehicles (AFVs) in challenging field conditions and remain fire-resistant even in the event of a direct hit.

"These days, tanks have lead-acid batteries and that's not good enough," Kost explains. “There are many electronic devices on tanks and vehicles, such as observation, anti-missile, and other systems, some of which work even when the vehicle is not moving. These systems consume a lot of energy. Accumulators based on lead-acid cannot provide energy for a long time, therefore, all the armies in the world are looking for solutions to increase the energy capacity of the vehicle, and the best thing that can be installed on an AFV today are lithium batteries.”

"In 2019, an American standard came out for lithium batteries for military vehicles," Kost adds. "No manufacturer has yet met this standard, and we’re in the middle of a project with the US Army to be the first to receive certification for military lithium-ion batteries. The great advantage of our battery lies in its ability to contain four times the energy of a lead-acid battery in the same battery size."

According to Kost, the main disadvantage of lithium batteries is their inadequate safety, but in the process of its research and development, Epsilor identified a comprehensive answer to this challenge as well. "We've all heard of electric scooter batteries catching fire at home or electric cars catching fire. In lithium batteries these risks are managed with the help of electronic equipment designed to ensure that the battery does not exceed its safe operating range. A system is installed inside the battery to report its status. As soon as it exceeds the safe operating range, a warning is issued, and if it continues for a long time, the battery disconnects and stops generating electricity. To further reduce the risk of fire, we are also developing a lithium-iron-phosphate battery that is considered particularly safe, with zero incidents of catching fire.”

The 6T batteries developed and manufactured by Epsilor enjoy significant technological advantages over the lead-acid batteries that are currently used in most military vehicles and tanks: the energy capacity of a lead-acid battery is 1 kilowatt hour (kWh), while lithium-iron-phosphate batteries have a capacity of 2.5 kWh and lithium-ion batteries a capacity of 4.2 kWh.

As far as the lifespan of the batteries is concerned, the Epsilor 6T batteries are greatly superior to those currently common in the market: compared to 300 charge cycles in a lead-acid battery, Epsilor's advanced batteries can reach 3,000 charge cycles. Furthermore, the batteries integrate a smart management system, have energy balancing capabilities, and provide more energy than competitors in the market.

Epsilor develops lithium-ion batteries and lithium-iron-phosphate 6T batteries. "Some customers prefer safety over performance and will opt for the lithium-iron-phosphate," he says. "Customers who have no choice but to compromise on safety will purchase the lithium-ion. Either way, this is the future of warfare. Since energy needs are increasing, there is no escaping the transition to high-voltage energy systems. Already today, Epsilor is planning a high-voltage system based on lithium-ion technology. In our estimation, in the next five years the demand for such systems on tanks and other military vehicles will increase greatly."

Hagai Shmuel, Epsilor's VP of Marketing and Sales, adds that Epsilor 6T batteries are currently at very advanced stages in development projects with various customers around the world. "We have several projects in various countries that have purchased this product for testing and evaluation purposes," he says. "Recently, we received an order for hundreds of batteries.”

The satellite of Tel Aviv University
Epsilor develops a wide range of tactical batteries in addition to those intended for military vehicles. "We have an entire family of batteries designed for the space industry," says Shmuel. "For example, when Tel Aviv University launched a nanosatellite into space called TAU-SAT3, we provided the battery that drives it."

The tiny battery developed by Epsilor for the Israeli nanosatellite took off into space in January, on a Falcon 9 rocket from SpaceX. The satellite is equipped with an optical device only a few centimeters long that required the development of a unique battery. Before the launch, Epsilor conducted several battery lifespan simulations, according to which it is expected to survive in space for at least ten years without needing maintenance.

"This is the pinnacle of technology as far as the development and choice of components is concerned. In space, there is a need for systems that can work outside the atmosphere for ten to fifteen years, which is a major technological challenge. The dimensions of the new battery are very limited, about 190 cc."

In the area of aviation, Epsilor has positioned itself as a significant and leading player in the development of batteries for drones, UAVs, and missiles. Here, too, the technological challenges are complex and will have far-reaching effects on the future battlefield: advanced batteries will allow drones to stay in the air longer and complete a larger variety of tasks.

In the development of batteries for military drones, it is necessary to meet strict requirements of durability. Among others, these drones operate in very low-temperature areas and are often at risk of damage. Therefore, battery safety is a highly valuable characteristic under these operational conditions.

As noted, Epsilor produces standard batteries that are intended mainly for communication devices and other products that soldiers in the field carry on themselves. "We supply these products to customers in Israel and worldwide, to the largest defense companies, and also to the Ministry of Defense," Shmuel explains.

Epsilor systems are present in other fields as well. During the outbreak of the Corona epidemic, the company provided a wide range of advanced products for medical systems. Among others, during the epidemic, Epsilor produced batteries designed for ventilators of various types, for other medical systems, as well as energy systems for temporary medical facilities deployed in the field. Mobile testing centers, hospitalization tents, refrigerated containers for vaccines — all made use of Epsilor advanced battery systems.

Innovation in all stages of production
Since its establishment, Epsilor has placed innovation at the center of all stages of research, development, and production. "In all stages of product development, including the stage of customer support, we adhere to the highest technological level. A battery consists of three parts: cells, electronics, and casing. Each of these components is required to meet strict standards," says Shmuel.

"A lot of innovation is embedded in our batteries," adds Ori Kost. "Innovation is reflected in everything related to the materials we integrate between the electrochemical cells, such as flame retardants and flame arresters. In addition, to increase safety, we develop various measures to quickly remove gases from the battery when it ignites. All these things fall under one important heading: developing a lithium battery with high survivability and improved safety. We use these technologies that are integrated into military batteries in our other batteries as well, and it is the strict requirements of the security products that push the technology forward."

In collaboration with Epsilor