5 Advancements in Solid-State Battery Beyond Lithium-ion Systems

Meet The Authors

Samsung made waves at the Seoul SNE Battery Day 2024 Expo by unveiling its revolutionary solid-state oxide battery. Utilizing the innovative LPSO sulfide electrolyte, these batteries promise a 600-mile range, 9-minute charging, and a 20-year lifespan. Samsung partnered with Toyota to mass-produce these batteries by 2027. Meanwhile, Japan’s TDK Corporation achieved a remarkable energy density of 1,000 watt-hours per liter in their all-ceramic, oxide-based solid-state batteries. Although this breakthrough will first arrive in wearables and other small devices, it is projected to revolutionize electric vehicles.

Lithium currently rules the EV battery market as it is light and has a high electrochemical potential, which allows for a high energy density. However, the International Energy Agency warns of a potential lithium shortage by 2025, prompting innovators to look for alternatives.

This research discusses five groundbreaking advancements in solid-state electrolytes that go beyond lithium-ion-based batteries:

1. Solid-State Sodium Silicate Battery (SSSB)

The Ram Charan Co (RCPL) in India has pioneered the development of the first solid-state sodium silicate battery, marking a significant milestone in the industry. Since 2021, RCPL’s R&D wing has diligently developed and tested the proof of concept (PoC) for this innovative battery. This recyclable battery employs naturally abundant sodium silicate as the cathode active material (CAM) and Na-enriched phyllosilicates as the solid electrolyte.

Although sodium-ion batteries face challenges, such as low gravimetric energy density and highly reactive sodium metal anodes, RCPL claims these can be mitigated by employing solid-state electrolytes with high Na+ ion conductivity and stability up to 600°C.

MD Kaushik Palicha and Research Associate Professor Harinipriya Seshadri filed a patent (WO2023242870A1) for this technology in June 2023. The SSSB is expected to be scaled up and tested in real-time applications by the end of 2024. It will likely transform electric vehicles (EVs), consumer electronics, low-power electronics, stationary storage, and space applications.

2. Solid-State Magnesium-ion Battery

RCPL has also achieved PoC for a recyclable solid-state magnesium battery that utilizes eco-friendly solid electrolyte. It uses magnesium-rich phyllosilicates for CAM and iron or magnesium-enriched phyllosilicates for the solid electrolytes. The battery has demonstrated a high power output of 0.89 kW/kg.

Kaushik Palicha and Harinipriya Seshadri filed a patent (WO2023238163A1) for this technology in June 2023. In January 2024, the technology was at TRL 5. RCPL plans to reach a TRL 9 product by early 2025 and target commercialization shortly thereafter. Potential areas for immediate application include low-power toys, watch batteries, e-mobility, stationary storage, and space applications.

With the rapid increase in scientific literature, patents, and research papers, finding relevant information has become as challenging as finding a needle in a haystack. R&D managers face several challenges in navigating through these never-ending databases for:

But what if an AI tool could browse and fetch credible data backed by citations for you? Accelerate your R&D efforts with actionable insights with Slate Pro. Click on the button below to get a demo.

3. Solid-State Potassium-Ion Battery

Ohio State University

Potassium-ion batteries (KIBs) are an attractive alternative to lithium-ion batteries due to potassium’s abundance in the earth’s crust and its high voltage potential. Researchers at Ohio State University have developed a novel solid-state electrolyte formula specifically tailored for potassium batteries, denoted as A(3-x)MyBwCz. In this tailored formula, A is K+, M is a metal cation (monovalent, divalent, or trivalent), B is O2-, and C is an anion (F-, Cl-, Br-, I-, CN-, NO2-, or a combination thereof). This breakthrough aims to enhance the safety and performance of potassium batteries, making them a viable alternative for clean transportation.

Dalian Institute of Chemical Physics (DICP)

Dalian Institute of Chemical Physics (DICP) in China has developed a new potassium-ion solid electrolyte, KNH₂. It has shown ionic conductivity reaching 4.84 x 10^-5 S cm^-1 at 150°C, which can be enhanced to 3.56 x 10^-4 S cm^-1 after mechanochemical treatment. The increase in ionic conductivity is attributed to the concentration of nitrogen defects in the KNH₂ electrolyte. This is the first report that adopts inorganic amide as an electrolyte for potassium-ion batteries and explores a new amide-based solid electrolyte for all-solid-state potassium-ion batteries.

Karlsruhe Institute of Technology – KIT

Researchers at Karlsruhe Institute of Technology (KIT) have developed a stable solid-state potassium battery composed of a potassium metal negative electrode, a Prussian blue analogue K₂Fe[Fe(CN)₆] positive electrode, and a poly(ethylene oxide)-potassium bis(trifluoromethanesulfonyl)imide polymer electrolyte. This configuration addresses the safety concerns and capacity losses associated with conventional flammable liquid electrolytes. Analysis showed that the solid-state battery achieved a superior capacity retention of 90% over 50 cycles at an elevated operating temperature of 55 °C. In contrast, a conventional carbonate-based liquid electrolyte reaches a capacity retention of only 66% operating at ambient temperature over the same cycle number interval.

4. Solid-State Calcium-ion Battery

When it comes to abundance and cost, calcium has the highest potential to be the future star of battery technology. Researchers at the Department of Biomedical and Chemical Engineering at Syracuse University are studying a novel calcium-ion solid polymer electrolyte (SPE) based on crosslinked poly(ethylene glycol) diacrylate (PEGDA). The developed SPE demonstrates an ionic conductivity of 3.4 × 10-4 S/cm at 110 °C and 3.0 x 10-6 S/cm at room temperature, which is similar to early-stage lithium SPEs.

5. Solid-State Zinc-Iodine Battery

Researchers at Songshan Lake Materials Laboratory in China have developed a solid-state zinc-iodine (ZnI₂) battery using a fluorine-rich solid perfluoropolyether (PFPE)-based polymer electrolyte. This innovation addresses common issues in zinc batteries, such as dendrite formation and iodine ion shuttling. The new battery features a stable solid electrolyte interphase (SEI) layer, promoting horizontal zinc growth and preventing dendrite penetration. The result is a battery with a long lifespan, achieving over 7,000 cycles with high capacity retention.

Conclusion

The solid-state battery market is set to skyrocket with a projected annual growth rate of 12.8% from 2024 to 2031. Battery technologies continue to advance with the rapid expansion of vehicle electrification requiring large battery packs. This has significantly increased the demand for more efficient, reliable, and eco-friendly alternatives. Therefore, scientists have been exploring various metals, including sodium, potassium, zinc, and calcium, as potential replacements for lithium-ion batteries. As these advancements move from proof of concept to commercialization, they hold the potential to transform not only electric vehicles but also portable electronics, grid energy storage, and more.

Uncovering such breakthroughs can help R&D Directors stay ahead in the market. Request a technology analysis on these battery advancements to gather research insights and understand the development stages. Click on the button below to talk to our industry experts today.