Next-Gen Batteries Get a Boost with Cold-Sintered Electrolytes

Engineers from Pennsylvania State University unveiled a novel manufacturing method for creating Solid-State Electrolytes to power next-generation batteries. The discovery pushes solid-state battery technology forward, opening the door for safer and more efficient portable power. Here’s what you need to know.

What Are Lithium-Ion Batteries and How Do They Work?

Lithium batteries have become the industry standard due to their power density, life cycle, and affordability. These devices utilize a chemical reaction to create a charge. They were first conceived in the 1970s after M. Stanley Whittingham at Exxon created the first stable lithium-ion battery setup, with the first commercial releases occurring in 1991 by Sony.

Today, lithium-ion batteries dominate the market. They are instrumental due to their ability to recharge. To accomplish this task, these batteries contain two internal electrodes connected by liquid electrolytes. This structure allows the electrolytes to connect the electrodes reliably and efficiently.

Why Lithium-Ion Batteries Can Be Dangerous: Risks and Drawbacks

Lithium-ion battery solutions have become the norm. However, they’re not without their risks and drawbacks. Lithium-ion batteries especially suffer from thermal runaway. This scenario involves the electrolytes leaking and becoming agitated. Eventually, this situation can lead to explosions and fires. As such, there has been a lot of media coverage on exploding batteries over the last couple of years.

Exploring Safer Alternatives to Lithium-Ion Batteries

In a quest to improve performance and reduce fire hazards, engineers continue to explore lithium-ion battery alternatives. These options range from mechanical batteries to solid-state options. The goal is to provide comparable power but reduce the risks and costs associated with lithium-ion solutions.

What Are Solid-State Batteries and Why Are They Safer?

The desire to create better batteries has led many to utilize solid-state batteries. These devices offer high energy density and power safety due to their composition. Solid-state batteries don’t utilize liquid electrolytes to connect the cathodes.

Instead, they rely on solid-state electrolytes that incorporate conductive materials that aren’t subject to fire hazards. Of these options, the NASICON-phase Li1.3Al0.3Ti1.7(PO4)3 (LATP) battery structure is the most effective.

Solid-state electrolytes are typically composed of polycrystalline grains, which can reduce connectivity. Notably, ion depletion across grain boundaries limits the performance of SSBs in many ways. For one, the crystalline structure requires additional materials to help induce connectivity.  As such, the grain boundary serves a vital role in preserving efficiency.

Challenges in Manufacturing Solid-State Electrolyte Batteries

It has been difficult to design and manufacture SSE-based batteries for many reasons. For one, each interface has its challenges that must be overcome. The cathode-electrolyte, electrolyte-boundaries, anode-electrolyte, and additive-electrolyte interfaces are expensive to manufacture, requiring high-temperature sintering to complete.

What Is Sintering and Why It Limits Solid-State Battery Progress

Sintering is a common process used to create battery electrolytes in SSBs. It’s been utilized in many designs, but has limitations to its effectiveness. For one, it requires very high temperatures. Notably, traditional sintering of ceramics requires the heat to reach 80% of the ceramic’s melting point, which can be around 1000 degrees Celsius.

Consequently, the sintering process can destroy additives and polymer compounds before the ceramic achieves its melting point. These factors continue to hinder SSB production and practical implementation. Thankfully, a team of engineers from Penn State believes they have solved this issue via some unique approaches.

New Penn State Study Unlocks Better Solid-State Electrolytes

The researchers revealed their progress in the Probing cold sintering-regulated interfaces and integration of polymer-in-ceramic solid-state electrolytes study^1, published in Materials Today Energy.  The study introduces a cold sintering process (CSP) that improves SSE production across the board by enhancing the process-structure-property correlation.

How Cold Sintering Improves Solid-State Battery Production

The cold sintering process can integrate dissimilar ionic conducting materials into polymer-in-ceramic (PIC) composite SSEs utilizing minimum heat and pressure. The process was inspired by nature. Specifically, the engineers reviewed the geological densification process to create the low-temperature sintering alternative.

Interestingly, the CSP was created in 2016 by a team of engineers led by Clive Randall. His upgraded approach allowed engineers to reduce conduction loss in ceramic-based SSEs, lowering manufacturing costs and improving overall efficiency. Additionally, the low-temperature CSP allows engineers to integrate distinct ionic conducting materials.

Key Upgrades That Make Cold Sintering More Efficient

To put the temperature change in perspective. Traditional sintering requires a minimum of 900 degrees Celsius. Keenly, the CSP occurs at 150 degrees. The lower temperature allows scientists to experiment with new materials and designs that wouldn’t hold up to traditional temperature requirements. This capability allowed the team to include new materials that improved performance.

Specifically, the group utilized LATP as a ceramic matrix alongside a poly-ionic liquid gel (PILG), which served as the conducting boundary phase. The group heated the powdered materials, treated them with solvents, and then compressed them into a dense form.

What Is LATP-PILG and Why It Matters for SSEs

LATP-PILG is a critical component of the new SSE design. It leverages PILG as a grain boundary in conjunction with LATP ceramic materials. This structure allows for the uniform distribution of a highly conductive PILG at the boundaries of LATP particles. This approach improves on previous designs because it enables ion transport across engineered boundaries versus through defect-prone natural interfaces.

Testing the Performance of Cold-Sintered Electrolytes

In-situ electrochemical impedance spectroscopy (EIS) was used to monitor real-time impedance changes during the densification process, providing insights into dynamic interface behaviors and allowing the team to monitor the interface formation and dynamic properties during the CSP.

Performance Results of the New Solid-State Electrolyte Design

The engineers behind the SSE study conducted several tests to ensure their research was accurate. The team utilized EIS to gather great detail and insight into SSE densification and interface properties. They noted that their creation achieved a high conductivity rate of 0.42 mS cm−1 and 5.15 × 10−4 S cm−1 in a coin cell and a split cell under 20 MPa. Notably, this test was taken at room temperature, furthering the engineer’s claim that the manufacturing process was far superior to traditional options.

Improved Voltage Windows in Solid-State Batteries

The team noted that the voltage windows for the SSEs were higher than previous variations of the battery tech. Specifically, a wide voltage window between 0 to 5.5 volts was registered. These readings are potentially up to 1.5 volts higher than lithium-ion competitors. The added performance comes from the ability to utilize high-voltage cathodes. Consequently, this approach enables SSEs to generate more energy overall compared to predecessors.

Top Benefits of Solid-State Electrolytes Over Lithium-Ion

There are many benefits that SSEs bring to the market. For one, they offer more reliable energy than liquid-powered battery alternatives. Also, they can be stored longer and more safely. Lithium-ion leaks are a major health risk that can result in fires, injuries, and even deaths. SSEs offer a better solution.

Improved Stability

SSEs are better suited for the high-impact and energy demands that most of your electronics experience. Lithium-ion batteries can become unstable under these conditions, resulting in failure or explosions. SSE-powered batteries can leverage different materials to create the ideal battery structure that incorporates a dense form designed to boost connectivity and stability.

Improved Conductivity

The engineers noted the high ionic conductivity at room temperature provided by these batteries. This data demonstrates how SSEs could replace lithium-ion alternatives in the future. For now, these devices offer more voltage via their structure, which enhances conductivity from the inside out.

Cycling Stability

Another major advantage of SSBs is that they provide longer life cycles compared to lithium-ion alternatives. Traditional batteries lose a little of their performance after each charge. While the loss rate is negligible, it adds up over time. The CSP allows engineers to charge batteries that can sustain reversible plating/stripping for hundreds of hours.

Safety

One of the biggest advantages of SSE batteries is that they are safer. Thermal runaway is a real problem for lithium-ion batteries that continues to cause harm globally. There are lots of videos online of scooters, cars, and even cell phones blowing up due to thermal runaway. Thankfully, SSE batteries don’t suffer from this problem, making them the best solution for many critical battery tasks.

Solid-State Battery Applications and 5-Year Production Timeline

The list of real-world applications for SSE batteries continues to expand. This technology could help power tomorrow’s high-performance wearables, laptops, phones, and electric vehicles. The lowered manufacturing costs and added cycle life make these batteries an ideal replacement for lithium-ion alternatives.

Cold Sintering in Manufacturing: Broader Industry Applications

The cold sintering process could revolutionize the manufacturing of ceramic composite materials across several industries. These materials serve a vital role in temperature management and more. In the coming years, manufacturers will turn to this option to reduce costs and improve flexibility.

How Cold Sintering Could Impact Semiconductor Manufacturing

Semiconductors are a critical component of today’s most advanced electronic devices. Being able to utilize a CSP to create more effective and thermally protected semiconductors could help propel tomorrow’s electronics to new heights. In the future, CSP will improve batteries and the chips used to power your devices.

When Will Cold-Sintered Electrolytes Be Commercialized?

According to the engineer’s estimates, this technology could be ready for production in the next 5 years. The team is confident in their methods, and since they utilize readily available material, integrating their process into existing processes would be cost-effective.

Solid State Electrolytes Researchers

The SSE study was conducted by Penn State researchers. The paper specifically lists Bo Nie, Ta-Wei Wang, Seok Woo Lee, Juchen Zhang, and Hongtao Sun as the contributing authors. Now, the team will seek to find industrial partners to help bring their manufacturing process to the market.

What’s Next for Cold Sintering and Solid-State Battery Tech?

The future of CSP is bright. This manufacturing process will be used to develop more sustainable systems that can support the growing energy demands globally. The next steps will include finding partners for large-scale production and working on ways to improve the recyclability of SSE-powered batteries.

Investing in the Battery Sector

The battery manufacturing sector is a billion-dollar industry that has tons of growth potential. The world is wireless, and batteries are the key to that scenario. As such, the demand for more powerful, lighter, and safer batteries will only rise in the coming years. Here’s one company expertly positioned to leverage this study.

Solid Power (SLDP +3.54%) is a publicly traded tier 1 battery manufacturer based out of Colorado. It was founded in  2011 by Doug Campbell, Conrad Stoldt, and Sehee Lee. Since that time, the firm has seen significant growth in its stock value and client lists.

Today, Solid Power focuses on supplying SSB to the EV market. Its work with alternative materials, including sulfide-based solid electrolyte, has helped the company climb the market to become a recognized name in battery tech. The main goal of Solid Power is to replace Lithium-ion batteries with safer and more reliable alternatives.

Solid Power continually spends on R&D to support its goal. Today, it is an industry-leading developer and manufacturer of advanced batteries with strategic partnerships globally. All of these factors make SLDP a smart stock to watch in the coming years as EV demand skyrockets.

Solid Power Stock News and Latest Developments

Solid-State Electrolytes: A Safer, Smarter Battery Future

The introduction of solid-state electrolytes is a game-changer across several industries. This scientific breakthrough will help guide engineers to the creation of ultra-performance batteries that don’t harm the environment and can operate safely after years of storage.

All of these factors, coupled with the additional uses for the CSP, give this study the potential to upend the battery industry in the coming years. For now, a salute to the engineers who successfully demonstrated how the CSP is a superior option.

Learn about other cool breakthroughs in energy tech now.

Studies Referenced:

^{1. Nie, B., Wang, T.-W., Lee, S. W., Zhang, J., & Sun, H. (2025). Probing cold sintering-regulated interfaces and integration of polymer-in-ceramic solid-state electrolytes. Materials Today Energy, 33, 101372. https://doi.org/10.1016/j.mtener.2025.101829}