[Interview] Lithium Metal Battery Pioneer UBATT Acquires ENNEX... "Developing Dry Electrode Process"

Lee Changgyu, CEO of UBATT
Doubling Energy Density with Uniform Thick-Film Electrode Technology
Acquisition of Electrode Equipment Company, Pioneering Dry Electrode Development

Yubet headquarters located in Daedeok Technovalley, Yuseong District, Daejeon. The container visible on the right side of the photo is a facility where developed batteries can be tested. Photo by Heejong Kang

In front of the headquarters of UBATT, a secondary battery startup located in Daedeok Technovalley, Yuseong District, Daejeon, rows of blue containers are lined up.

First-time visitors often mistake them for energy storage systems (ESS), but in reality, these are facilities for testing and analyzing batteries under development. The idea is to prevent a fire that might occur during battery testing from spreading to the entire building. Other research institutions are reportedly benchmarking this facility.

UBATT is a leading company in lithium metal batteries in Korea. Lithium metal batteries are secondary batteries that use lithium metal as the anode. Lithium metal has a theoretical capacity more than 10 times greater than graphite, which is currently used as a standard material, allowing it to store much more energy than current lithium-ion batteries.

UBATT was founded in October 2016 and is now entering its tenth year. In July of last year, the company moved out of rented offices and into its current headquarters. The first floor of the three-story headquarters is equipped with a mini pilot (test production) line capable of producing 10 megawatts (MW) per year. Here, the company manufactures samples of its uniform thick-film electrodes (TEP-Thick Electrode Platform) and lithium metal batteries for clients.

On the second floor, there is cycler equipment capable of charging and discharging 1,000 batteries simultaneously. The entire first floor and part of the second floor are maintained as dry rooms, completely blocking humidity.

Lee Changgyu, CEO of Ubat (left in the photo), is discussing battery electrode equipment with an employee. Ubat

"It cost about 10 billion won just to equip the facility." Lee Changgyu, CEO of UBATT, said proudly as he guided the reporter through the facility on November 4. UBATT has received a cumulative investment of 16.2 billion won to date, most of which has been spent on purchasing equipment.

Thanks to this, UBATT has been able to achieve a high level of manufacturing capability. Yoo Jongtae, Chief Planning Officer (CPO, Executive Director) at UBATT, emphasized, "We are fundamentally different from other startups that exist in name only and have no substance."

So far, UBATT has attracted investment from Hyundai Motor Group, KDB Industrial Bank, Sopoong Ventures, POSCO Technology Investment, D3 Jubilee Partners, BM Ventures, and Golden Oak Ventures.

'Double the Energy Density' Uniform Thick-Film Electrode Technology, Technical Collaboration with Major Manufacturers

The technology that UBATT is most proud of is its uniform thick-film electrode. This technology allows the materials that make up the electrode to be distributed evenly, enabling the production of thicker electrodes.

The thicker the electrode, the more energy it can store. A single battery is made by stacking multiple unit cells consisting of a cathode, separator, and anode. Thicker electrodes allow for a reduction in the number of stacks, thereby lowering costs.

A diagram explaining UBATT's uniform thick-film electrode technology. The left illustration describes the migration (layer separation) phenomenon during the drying process when manufacturing thick electrodes for typical lithium-ion batteries, where relatively light conductive agents and binders float upward. In contrast, the right illustration shows that when UBATT's technology is applied, even with thick electrode manufacturing, active materials, conductive agents, and binders are uniformly distributed. UBATT

Electrodes are manufactured by mixing active materials, conductive agents, and binders in an organic solvent, coating them onto a current collector (aluminum foil or copper foil), and then drying them. If the electrode is too thick, during the drying process, the heavier active materials sink while the relatively lighter conductive agents and binders float upward, causing a migration (layer separation) phenomenon. This disrupts electron flow and degrades battery performance.

Lee explained, "We developed a special additive that suppresses layer separation, enabling us to manufacture thick electrodes." UBATT is using its uniform thick-film electrode technology to develop its own batteries while also pursuing technical collaborations with global automakers and battery companies.

UBATT has developed a lithium metal battery called 'Stratos,' which features a uniform thick-film electrode on the cathode and lithium metal on the anode. The energy density reaches 600 watt-hours per kilogram (Wh/kg). This product won an award in the startup category at the 'InterBattery Awards 2025' held last March.

Lee explained, "The actual energy density of mass-produced products will be around 450 to 500 Wh/kg." This is about twice the performance of typical lithium-ion batteries that use graphite as the anode material.

Lee Changgyu, CEO of Ubat, is introducing Ubat's high-capacity lithium metal batteries and lithium-ion battery products. Ubat

'Stratos' is a word inspired by 'stratosphere,' referring to the atmospheric layer between 10 and 50 kilometers above the Earth's surface, and signifies the battery's powerful output, sufficient to send aircraft into the stratosphere. As the name suggests, UBATT's lithium metal batteries are primarily targeting the drone and unmanned aerial vehicle market.

The unmanned aerial vehicle market is where the advantages of lithium metal batteries-being lightweight yet storing large amounts of energy-can be best realized. Lee explained, "The electric vehicle and ESS markets are already dominated by large companies with mass production systems, making it difficult to enter. However, the defense sector, which requires small-batch, multi-variety production, is a market where startups like us can compete."

The biggest weakness of lithium metal batteries is their tendency to form dendrites. Dendrites are lithium crystals that grow in a tree-branch shape from the anode. If severe, they can penetrate the separator, causing a short circuit between the cathode and anode and potentially resulting in a fire. Despite the high energy density, this is why lithium metal batteries have not yet been installed in electric vehicles.

Lee said, "We are applying various core technologies to control dendrite formation," and added, "Since drones require fewer charge/discharge cycles and pose no risk to human life, they are the most suitable field for the initial commercialization of lithium metal batteries."

Lee Changgyu, CEO of Ubat, is explaining the stacking equipment, one of the secondary battery assembly devices. Ubat

UBATT is particularly focusing on the U.S. defense market. As security concerns grow, there is a movement in the U.S. defense sector to exclude Chinese batteries, creating opportunities for Korean battery companies. Lee stated, "We are discussing battery collaboration with U.S. defense-related agencies."

Acquisition of Electrode Equipment Company ENNEX...Pushing into Dry Electrode Technology

As part of its efforts to enter the U.S. market, UBATT recently acquired ENNEX, a small battery equipment company based in Daegu. Lee said, "We acquired the equipment company to meet the battery manufacturing capabilities required in the U.S. market," and added, "From next year, we plan to begin full-scale negotiations."

The workforce of ENNEX will be integrated into UBATT's Process Business Division. This division will be responsible for securing production technology as well as developing electrode equipment. In particular, UBATT expects to create synergy with ENNEX in the development of dry electrode processes.

UBATT was founded in 2016 by CEO Lee Changgyu and Professor Lee Sangyoung of the Department of Chemical and Biomolecular Engineering at Yonsei University (then a professor at UNIST). CEO Lee graduated from the Department of Chemical Engineering at KAIST and obtained a master's degree in Techno-MBA from the same university. Professor Lee graduated from the Department of Industrial Chemistry at Seoul National University and earned his master's and doctoral degrees in chemical engineering from KAIST. He moved into academia after researching batteries at LG Chem for 12 years.