Senior Researcher Park Jae-bum POSCO Research Institute

The Hot Topic of Humanoid Robots! Why Are All-Solid-State Batteries Attracting Attention?

At ‘CES 2026’, held with great enthusiasm earlier this year, the most talked-about topic was humanoid robots. Immediately following the exhibition, interest in humanoid robots surged, leading to a significant rise in the stock prices of robot-related companies. Humanoid robots are designed to perform dangerous or complex tasks in place of humans in workplaces requiring high-intensity labor. Their potential for application across various fields, from daily life to industrial sites, is garnering significant attention.

▲ The ‘next-generation electric Atlas research model’ (left) and ‘next-generation electric Atlas open model’ (right) unveiled at CES 2026. Image source: Hyundai Motor Group]

Another hot topic alongside humanoid robots is the all-solid-state battery. An all-solid-state battery is a next-generation battery that replaces the liquid electrolyte, a core material of lithium-ion batteries, with a solid electrolyte. Thanks to the use of a solid electrolyte, it possesses high safety, and based on this, it allows for the improvement of other materials, enabling an increase in the battery’s energy density. In other words, it is one of the suitable battery candidates that meets the energy density and safety requirements demanded by humanoid robots.

Robots, especially humanoids, have limited space for battery installation. Unlike electric vehicles (EVs), it is difficult to mount a large amount of batteries, which limits battery capacity. Therefore, batteries with high energy density per weight and volume are essential for robots. Additionally, since robots must be able to lift heavy objects and perform quick movements instantaneously, high power output is also expected to be a critical factor in battery performance. While all-solid-state batteries are evaluated as capable of meeting these requirements in the future, they are still in the pre-commercialization stage and are currently very expensive.

However, when looking at the proportion of the battery in the total cost, there is a clear difference between EVs and robots. Unlike EVs, where the battery cost accounts for a relatively high portion, the price proportion of the battery in robots is relatively low. Therefore, even if an all-solid-state battery is installed, the price increase for the robot is smaller than that for an EV. For this reason, humanoid robots are being discussed as a promising initial application field once all-solid-state batteries are commercialized.

Between Expectation and Reality… Barriers That All-Solid-State Batteries Must Overcome

Despite these technical advantages and high market expectations, it is difficult for all-solid-state batteries to lead to immediate commercialization in the short term. Even setting aside the problems to be solved in the mass production process, the barrier of high cost still exists.

Assuming the commercialization price of a humanoid robot is $5,000 per unit, even if the battery is switched from a ternary NCM (nickel, cobalt, manganese) battery to an LFP battery, the price reduction for the robot is only about 1.9%. In other words, because robots use a small amount of batteries per unit, it is difficult to expect the same cost-saving effect as in EVs by using LFP. What if an all-solid-state battery is applied? It is estimated that the robot price would increase by about 14–17%, and the cost proportion of the battery would rise to the 20–24% level.

Although it varies depending on the characteristics and use of the robot, the industry considers a battery cost share of around 10% to be appropriate for humanoid robots. This is because, in addition to the battery—the heart of the humanoid—there are many other necessary parts and modules, such as actuators (joints), grippers (hands), and AI (the brain), making it difficult to allocate a large portion of the cost to the battery. Therefore, even assuming a maximum cost proportion of 15% considering the performance improvement of the robot due to the application of an all-solid-state battery, the price of all-solid-state batteries needs to drop to the $350/kWh level.

Key challenges for the commercialization of all-solid-state batteries

The main reason for the high price of all-solid-state batteries is the lack of a stable mass production system, but the high price of the core material, solid electrolyte, is also a major factor. The cost of the solid electrolyte material alone exceeds the price of a lithium-ion battery. This is because the price of lithium sulfide (Li₂S), the core raw material for solid electrolytes, remains high at about $500/kg, and because they are mainly manufactured in lab or pilot lines, the ‘economies of scale’ effect—where the average price decreases as production volume increases—has not yet occurred. For all-solid-state batteries to secure price competitiveness compared to lithium-ion batteries, the price of solid electrolytes appears to need to drop to the $30/kg level.

For commercialization, technical challenges remain in addition to price. While improving the safety of all-solid-state batteries is possible just by applying the core solid electrolyte material, improving other materials is also necessary to ultimately increase energy density. Furthermore, to improve peak output (lasting from a few seconds to tens of seconds), technical hurdles such as improving ionic conductivity and overcoming interface resistance must be resolved. Currently, major global companies are actively pursuing material-centered R&D to overcome these limitations.

Despite various issues, all-solid-state batteries are still considered a very suitable next-generation battery technology for robots. This is because they are not only safer than LFP batteries but also have significant room for improvement in energy density. This is expected to improve not only the robot’s operating time but also its peak output performance, which lasts from a few seconds to tens of seconds. Ultimately, whether the substantial improvement in robot performance—such as energy density, peak output, and safety—is clearly proven to offset the burden of increased costs due to the application of all-solid-state batteries will be the key criterion for judging future commercialization.

‘Dream Battery’ All-Solid-State Battery, Can It Accelerate the Timing of Commercialization?

All-solid-state batteries have long been called the ‘dream battery’ and have received high expectations in the secondary battery market, but they still face the challenge of securing mass-producibility and price competitiveness similar to that of lithium-ion batteries. Until now, suitable demand sources for all-solid-state batteries have been limited, but recently, the possibility that the market opening time could be advanced, defying previous expectations, has been raised.

① Before Electric Vehicles? The Potential for Robot Market Application

Among domestic battery manufacturers, Samsung SDI has presented a relatively concrete timeline for the mass production of all-solid-state batteries. The company is targeting 2027 for mass production and is reportedly reviewing the potential for application in various new fields, including robotics. If these plans materialize, all-solid-state batteries could be adopted in non-automotive sectors—such as robotics—before they are widely used in electric vehicles. In particular, because the sample testing and certification processes for robots are relatively more flexible than those for EVs, there is significant potential for the market landscape to shift rapidly.

② China’s Announcement of National Standards for All-Solid-State Batteries

Meanwhile, changes in the global policy environment are acting as a catalyst to accelerate the opening of the all-solid-state battery market. The Chinese government recently announced national standards for all-solid-state batteries, establishing clear terminology and a classification system. This is interpreted as a strategic move to secure market leadership, with a focus on next-generation applications such as robots and eVTOLs*. Major Chinese battery firms are accelerating development with a goal of commercialization around 2027; if coupled with government support, the initial cost burden is expected to be partially mitigated. These national standards and policy supports are significant, as they can accelerate market formation regardless of the current level of technical maturity. In response, Korea is also seeking policy measures, such as securing production bases for core materials and expanding R&D support for next-generation batteries.

*eVTOL (Electric Vertical Take-Off and Landing): An aircraft that uses electric power to hover, take off, and land vertically.

③ The Time Until Commercialization: The Importance of a ‘Pivot Strategy’

The price of all-solid-state batteries during the initial mass production and pilot stage in 2027 is estimated at $400–600/kWh, and a transition to full-scale commercial production is likely to occur only after 2030. However, it is expected that all-solid-state batteries will periodically emerge as a key market topic over the next three to four years, with the construction of material supply chains proceeding in parallel. In this rapidly changing environment, experts argue for the necessity of a ‘pivot strategy*.’ This means that rather than simply waiting for the all-solid-state battery market to open, companies must strengthen their existing lithium-ion battery competitiveness while simultaneously preparing to pivot quickly to all-solid-state technology as the market evolves.

*Pivot: A strategy of changing direction or focus while maintaining the existing core business.

POSCO Group Preparing for the Era of All-Solid-State Batteries

POSCO Group has been preemptively conducting research, development, and investment in core materials such as cathode materials for all-solid-state batteries, lithium-metal anodes, and solid electrolytes. To secure competitiveness in the solid electrolyte business, which is the core of all-solid-state batteries, POSCO Group invested a 40% stake in Jeong-Kwan Co., Ltd. in February 2022 to establish POSCO JK Solid Solution. The company is currently operating a pilot plant and is conducting sample tests for global battery companies and OEMs.

In addition, POSCO Group is accelerating the development of next-generation materials—such as solid electrolytes, high-capacity cathodes, and silicon anodes—through strategic partnerships and equity investments in industry leaders like Taiwan’s ProLogium and the U.S.-based Factorial Energy. Furthermore, the group is moving to internalize the production of lithium sulfide, a core raw material for sulfide-based solid electrolytes, to drive down costs and secure a more economical supply chain.

▲ Panoramic view of POSCO Future M’s Pohang cathode material plant.

Recently, POSCO Future M signed an MOU with Factorial, an all-solid-state battery company headquartered in Massachusetts, USA, for the development of all-solid-state battery technology. Through this cooperation, it is expected that POSCO Future M’s material technology and Factorial’s global partnership capabilities will be combined to secure competitiveness in the all-solid-state battery market.

As such, POSCO Group plans to continuously expand its portfolio of core materials for all-solid-state batteries, including cathode materials for all-solid-state batteries, silicon/lithium-metal anode materials, and sulfide-based solid electrolytes, centered on POSCO Future M, which possesses material design and coating technologies.

CES 2026, the world’s largest technology trade show, has come to a close—and this year, one theme stood out above all others: robots. From humanoids and quadrupeds to sports and healthcare applications, robotics was everywhere on the show floor, signaling that the era of Physical AI—where AI and robotics come together in the real world—is quickly taking shape.

With Jae-bum Park, Senior Researcher at POSCO Research Institute, we look at what CES 2026 revealed about the future of robotics and where POSCO Group’s strengths could create new opportunities in this fast-growing industry.

Powering the Energy Transition: Robots Were Everywhere at CES 2026

At this year’s CES, robots were impossible to miss. Even in booths hosted by companies not traditionally associated with robotics, robot-related technologies appeared throughout the exhibition. The message was clear: AI-powered robots are moving beyond demonstrations and entering everyday life and industrial environments.

One of the most talked-about exhibits was Atlas, the humanoid robot presented by Boston Dynamics, Hyundai Motor Group’s robotics affiliate. Equipped with 56 degrees of freedom (DoF), Atlas demonstrated highly flexible movement and the ability to handle heavy-duty tasks involving loads of more than 50 kilograms—offering a glimpse of its potential in real industrial settings.

The exhibition also introduced a collaboration case involving POSCO and Boston Dynamics. On screen, Spot, Boston Dynamics’ quadruped robot, was shown moving through high-temperature facilities at a POSCO steelworks. In a noisy and heat-intensive environment, Spot was able to detect gas leaks and carry out precise inspections of equipment and infrastructure. The scene offered a compelling look at how robots are evolving from crowd-pleasing exhibits into reliable co-workers on industrial sites.

Another exhibit that drew attention came from Korean company Bodyfriend, which showcased a massage chair designed to feel almost like wearing a robotic suit. Its wearable AI healthcare robot, with independently moving arms and legs, attracted strong interest for its ability to analyze and stretch the user’s joints.

Robots were also making an impact in sports. Table tennis robots and combat robots once again proved popular with visitors, while sports robots introduced by Chinese companies such as Unitree and others showed just how far the technology has advanced. Some were able to analyze an opponent’s movements and track the trajectory of a ball in real time, providing highly detailed coaching.

Degrees of Freedom: What Makes Robot Movement More Sophisticated

As CES 2026 made clear, robot movement is becoming increasingly refined as technology advances. One term that many robotics companies use when discussing precision and flexibility is DoF, or Degree of Freedom. In simple terms, DoF refers to the number of joint axes a robot can move or control.

Generally speaking, the higher the DoF, the more independently controllable joints a robot has. This is particularly important for humanoid robots, which are expected to move in ways that resemble the human body. Industrial robot arms used in automated manufacturing processes typically have around 6 DoF, while humanoid robots usually range from 30 to 60 DoF. With 56 DoF, Boston Dynamics’ Atlas is close to the level required to mimic full-body human joint movement.

That said, increasing DoF also means adding more components such as motors, reducers, and sensors. In other words, the more sophisticated the movement, the higher the production cost. That is why robotics companies carefully design and allocate DoF based on each robot’s purpose and application.

Why Actuators Matter

An actuator is the drive unit that physically moves a robot’s joints. It can be understood as a complete joint system that combines a motor, reducer, sensor, and control circuit.

A motor on its own produces rotational motion. But for a robot arm to extend in a straight line or bend with precision, rotational movement alone is not enough. By integrating gears and electronic controls, an actuator enables more complex forms of motion, including both rotational and linear movement. If a motor is like a muscle cell, an actuator is the complete muscular joint that allows a limb to move in a controlled way.

For a humanoid robot with 56 DoF, roughly 56 precision actuators are needed.

Why Hyper NO Matters in the Age of Robotics

Electrical steel is also a critical material in motor manufacturing, accounting for roughly 20% to 30% of total motor production cost. This is especially important in robot motors, which must generate high output despite their compact size. In many cases, the performance of the electrical steel used inside the motor directly affects the motor’s overall efficiency and output.

To achieve better performance, the steel sheet must be made as thin as possible. If it is too thick, eddy currents* can form inside the material, causing energy loss in the form of heat.

*Eddy currents are swirling electric currents generated by electromagnetic induction when the magnetic field around a conductor changes rapidly.

POSCO’s high-performance electrical steel, Hyper NO, is designed to maximize magnetic performance even at extremely thin, paper-like thicknesses. The thinner electrical steel becomes, the more difficult it is to manufacture. In fact, only about five to six steelmakers worldwide, including POSCO, are capable of stably mass-producing electrical steel at the Hyper NO level. That makes it a strategic material with high technological barriers to entry—and an increasingly important one in the era of robotics and electrification.

Energy and Materials Will Help Power the Humanoid Robot Era

No matter how advanced a robot’s movement may be, it cannot function properly without enough energy. Today, humanoid robots typically operate continuously for only about two to four hours, making battery technology one of the biggest limiting factors in the industry.

At CES 2026, swappable battery systems emerged as a notable trend aimed at addressing that limitation. Boston Dynamics’ Atlas, for example, is known to operate continuously for around four hours, and it is even equipped with a function that allows it to replace its own battery when power runs low.

Tesla CEO Elon Musk recently predicted that there could be 10 billion humanoid robots within 25 years. If production reaches that scale, demand for actuators would rise into the hundreds of billions, making growth in demand for high-performance electrical steel almost inevitable. Once replacement demand is taken into account, the number of batteries required could also reach into the tens of billions.

This would also drive a sharp increase in demand for lithium, one of the key raw materials used in batteries. From this perspective, POSCO Group’s high-performance electrical steel technology and lithium assets are likely to draw growing attention as the robotics market continues to expand.

As robotics moves closer to real-world adoption, the future of the industry will depend not only on software and AI, but also on the materials and energy technologies that make advanced movement possible. In that future, POSCO Group is well positioned to play an important role.

Establishing a Collaboration Model Between Workers and Humanoid Robots to Expand Physical AI to Heavy and Heavy Industries

POSCO Group is accelerating the adoption of physical AI in manufacturing sites by pursuing a project to apply humanoid robots to steel product logistics management.

On the 3rd, POSCO Group signed an MOU at the POSCO DX Pangyo headquarters with representatives from four companies: POSCO, POSCO DX, POSCO Investment, and Persona AI, to implement industrial humanoid robots in the field.

Under the agreement, POSCO will identify potential work sites at its steelworks and assess their feasibility. POSCO DX will design and build a robot automation system and jointly develop a steelworks-specific model. POSCO Investment will support the implementation of a Proof of Concept (PoC), a small-scale preliminary test of ideas and technologies to determine their practical feasibility. Persona AI will be responsible for the development and implementation of a humanoid robot platform tailored to the steelworks industrial environment.

POSCO Group and Persona AI have agreed to begin testing Persona AI’s humanoid robot business in the logistics management of steel coils produced at the steelworks in February. Unloading rolled coils weighing tens of tons requires crane operation. The humanoid robot will collaborate with field workers to attach the crane belt to the coils. This is expected to be an example of human-robot collaboration creating a safer work environment.

Logistics work involving handling coils weighing 20 to 40 tons carries a high risk of accidents and the potential for musculoskeletal disorders due to repetitive tasks. The deployment of humanoid robots is expected to address these issues. Since last year, POSCO Group has been considering the introduction of humanoid robots in terminal logistics processes, such as transportation and material preparation, considering the characteristics of heavy construction sites. If this demonstration process confirms the mechanical safety and collaboration potential of humanoid robots with workers, the group plans to expand their deployment and apply them to various logistics sites.

Persona AI is a US-based humanoid robot startup founded in 2024 by renowned robotics engineers and industry experts. Prior to this agreement, POSCO Group invested a total of $3 million in Persona AI last year. Combining NASA’s robotic hand technology with its own precision control technology, Persona AI is developing industrial humanoid robots capable of everything from assembling fine components to handling heavy loads.

To respond promptly to the industrial paradigm shift, including AX, POSCO Group plans to expand its Intelligent Factory initiative across its manufacturing sites and create a safe and comfortable, technology-based workplace.

▲ (From the second from the left in the front row, moving right) Kyuho Chung, Head of POSCO DX Strategy Office; Minseok Shim, President & CEO of POSCO DX; Nicolaus Radford, CEO of Persona AI; Geunhwan Kim, President of POSCO Venture Capital, along with business representatives, pose for a commemorative photo after signing a Memorandum of Understanding (MOU) at POSCO DX’s Pangyo office for the on-site application of industrial humanoid robots.

Introducing Humanoid Robots Specialized in Heavy-Duty Industrial Sites to Enhance Productivity and Safety

POSCO Group is investing in a US-based company specializing in industrial humanoid robots to actively expand the use of physical AI in the field, combining its AI technology with robots.

POSCO DX (CEO Shim Min-suk) announced a $2 million investment in US-based industrial humanoid robot company ‘Persona AI’ and will actively collaborate on joint robot development and field application. This investment was made through the “POSCO DX Corporate Venture Capital (CVC) New Technology Investment Fund,” funded by POSCO DX and POSCO Capital in the second half of this year. An additional $1 million was invested through the “POSCO CVC Scale-Up Fund No. 1,” also funded by POSCO Capital, bringing the total investment to $3 million across the POSCO Group.

Founded in June 2024, Persona AI is an industrial humanoid robot company developing robots specialized for high-intensity, heavy-duty industrial sites. Co-founded by CEO Nicolaus Radford, a former NASA robotics engineer, and CTO Jerry Pratt, former CTO of Figure AI, a US humanoid robot company, the company is now CTO.

Based on NASA’s robotic hand technology, Persona AI implements precision control capabilities capable of everything from fine part assembly to heavy-duty handling. In addition, the company possesses multi-axis tactile sensing and adaptive control technology. This technology integrates data acquired through the robot’s multi-axis tactile sensor in real time to simultaneously control force and position, enabling the robot to perform stable tasks even in uneven environments. Furthermore, Persona AI applies an AI control algorithm based on the Robot Foundation Model (RFM), which acts as the robot’s brain, enabling the robot to autonomously interact with its surroundings and perform advanced tasks.

With this investment, POSCO DX plans to develop a detailed collaboration plan for the development of humanoid robots that can replace high-risk manual processes in the group’s industrial sites. The company explains that by combining its own industrial AI technology with Persona AI’s robotics technology, it will accelerate the spread of physical AI. Previously, POSCO DX is working with POSCO to implement physical AI, which efficiently controls large-scale equipment such as cranes, conveyor belts, and unloading machines at steel mills without human intervention.

The US investment bank Morgan Stanley forecast in a report that the global humanoid market will grow by an average of 63% annually, reaching approximately $38 billion (approximately 54 trillion won) by 2035, with manufacturing and logistics accounting for 60% of the market.

Meanwhile, POSCO Group is expanding its corporate venture capital (CVC) fund, which focuses on venture investments to identify innovative technologies and promising future businesses, from its existing focus at POSCO Holdings to a customized platform for each operating company. In August of this year, POSCO established its first CVC fund, with 50 billion won each for POSCO International and POSCO DX.

▲ Image of a humanoid robot model being developed by Persona AI.