Fluorine & Tofu Brine Lead To Battery Breakthroughs In China

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While the US focuses on extracting and burning coal just like the world did in the 19th century, researchers in China are actively engaged in finding new, less expensive batteries with higher power and longer service life. While America looks back wistfully to its horse and buggy roots, China is preparing for an all-electric future.

According to China Daily, Chinese scientists led by Chen Jun, an academician of the Chinese Academy of Sciences and vice president of Nankai University in Tianjin, have developed a lithium metal battery that boasts an energy density of more than 700 watt-hours per kilogram and stable performance at extremely low temperatures. This marks a significant advancement in the production of high-energy batteries for electric vehicles. The research paper was published on Thursday in the science journal Nature. Here is the abstract to that journal entry, which was published on February 25, 2026:

Electrolyte solvents for electrochemical devices have been dominated by oxygen (O)-based and nitrogen (N)-based ligands over the past decades, for which the dipole–ion (Li+, Na+ and so on) interaction usually lays the foundations of ion dissociation and transport but frustrates the charge transfer process at the electrolyte–electrode interface.

Here, by synthesizing alkanes with monofluorinated structures, we show that fluorine (F)-based ligands with designed steric hindrance and Lewis basicity enable salt dissolution of more than 2 mol l. Among them, 1,3-difluoro-propane (DFP)-based Li-ion electrolyte is endowed with all merits for energy-dense and low-temperature batteries, including low viscosity (0.95 cp), high oxidation stability (>4.9 V) and ionic conductivity of 0.29 mS cm at −70 °C.

By incorporating F atoms in the first solvation shell, the weak F–Li+ coordination facilitates the Li plating/stripping process with Coulombic efficiency (CE) up to 99.7% and exchange current density one magnitude larger than O–Li+ coordination at −50 °C.

The electrolytes further enable the operation of lithium-metal pouch cells under an electrolyte amount of less than 0.5 g Ah, achieving energy densities greater than 700 Wh kg at room temperature and about 400 Wh kg at −50 °C. The hydrofluorocarbon (HFC) electrolytes in this work provide a feasible approach to building electrochemical systems beyond traditional coordination chemistry.

Okay, got all that? Here’s the plain language translation: Chen said the team has replaced oxygen atoms with fluorine ones. It designed and synthesized novel fluorinated hydrocarbon solvent molecules, which created a new electrolyte system based on lithium-fluorine coordination.

Laboratory tests showed that the battery could achieve energy density above 700 watt-hours per kilogram, maintaining nearly 400 Wh/kg at -50°C. Energy density and low-temperature performance are the biggest bottlenecks hindering the widespread adoption of EVs, Chen said.

To address this challenge, his team redesigned the battery electrolyte at the molecular level. By developing fluorinated hydrocarbon solvent molecules and establishing a lithium-fluorine coordination system, the researchers improved ion transfer and enabled stable operation at ultrahigh energy densities and extremely low temperatures.

“High-energy batteries using this electrolyte have vast potential in new energy vehicles, embodied intelligent robots and the low-altitude economy, as well as in polar regions, aerospace and aviation,” Chen said.

The team has also made significant progress in advancing cutting-edge technologies toward practical applications. Earlier this month, the team collaborated with Chinese automaker Hongqi to release a mass-producible ultra-high energy density lithium-rich manganese solid-liquid battery system. The system boasts a cell energy density exceeding 500 Wh/kg, which translates into a driving range of more than 1,000 kilometers on a single charge for equipped vehicles.

Yan Zhenhua, a professor at Nankai University’s College of Chemistry, said the new battery uses a self-developed composite electrolyte that improves both safety and durability. “It not only achieves a leap in energy density but, more important, solves the high cost and high risk challenges associated with lithium metal batteries, significantly enhancing cycle life and intrinsic safety,” Yan added.

Lu Tianjun, general manager of China Automotive New Energy Battery Technology, said that vehicles equipped with the batteries and capable of exceeding 1,000 kilometers per charge are expected to enter mass production by the end of this year. “This serves as a model and a leading example of collaboration between universities and enterprises.”

“This battery, whether in terms of energy density, technological advancement or progress in application, represents a leading level both domestically and internationally,” Lu said. “Conservatively, its performance would mean an improvement of about 50 percent compared with current technologies.”

Chen, the Nankai University researcher, said that translating scientific breakthroughs into practical technologies requires close collaboration between researchers and industry. “We can’t always stay in the ivory tower. Our goal is to address real industrial challenges.”

Tofu Brine To The Rescue!

OilPrice.com also has a report this week about a new aqueous battery developed by Chinese researchers that purports to be capable of 120,000 charge/discharge cycles. Aqueous batteries have not proven to be well suited for powering automobiles, but they could play an important role in battery energy storage systems. The typical life cycle limit for lithium-ion batteries is around 3,000 charge/discharge events. Once again, for our technically inclined readers, here is the abstract for this study, which was published in Nature Communications on February 18, 2026:

The electrolytes of aqueous batteries are mostly acidic or alkaline, resulting in inevitable side reactions. More importantly, when batteries are disposed of, strongly acidic and alkaline solutions harm the environment.

In this study, we synthesized covalent organic polymers as negative electrode materials for aqueous divalent ion (Mg2+ and Ca2+) storage, which exhibit favorable performance in electrolytes with a pH of 7.0 (the electrolytes are environmentally benign and can even be “brine” in tofu production).

Polymers containing electron-donating linking bonds exhibit fast kinetics and low potential for use in aqueous Mg2+/Ca2+ batteries. In neutral electrolytes (pH = 7.0), Hexaketone-tetraaminodibenzo-p-dioxin covalent organic polymers exhibit 120,000 cycles and deliver specific capacities (up to 112.8 mA h/g).

The negative electrode was paired with a positive electrode, creating a full cell that has a voltage interval of 2.2 V and achieves a specific energy of up to 48.3 Wh/kg, which is calculated on the basis of the total mass of the negative electrode, positive electrode, and electrolyte at the full cell level, together with long-term cycling stability over 120,000 cycles at a specific current of 20 A.

The full cells are environmentally benign and nontoxic and can be directly discarded to environments according to various standards (GB 18599-2020, ISO 14001, Resource Conservation and Recovery Act RCRA, US).

“Compared with current aqueous battery systems … our system delivers exceptional long-term cycling stability and environmental friendliness under neutral conditions,” the research team said. It was composed of scientists from the City University of Hong Kong and Southern University of Science and Technology in Shenzhen.

“At over a hundred thousand cycles, this could mean a single water based battery could last at least a decade or so. For applications like grid storage (solar farms, wind balancing), that’s extremely valuable,” they claim.

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These tofu-brine batteries could prove safer and more environmentally friendly than lithium-ion batteries. According to the study authors, the full cells are environmentally benign and nontoxic and can be directly discarded to environments while meeting national and local disposal standards. Water-based (also called aqueous) batteries can also be cheap to produce, as they rely on ingredients that are far less costly than those used in conventional lithium-ion batteries.

If this new tofu-brine battery proves scalable and applicable outside of a laboratory environment, it could be another step toward Beijing’s goal of near-total domination of clean energy technology value chains and status as the world’s first and premiere “electro-state,” says OilPrice.com reporter Haley Zaremba.

While other countries are aware of China’s dominance in clean energy technologies — largely because of its solid support of basic research — and are taking pains to protect and promote domestic battery manufacturing, those efforts may be too little, too late.

“For globally competitive battery manufacturing industries to emerge outside of Asia over the next ten years, companies will need to do far more than ensure regulatory compliance,” summarizes a McKinsey & Company report released in January. “Challenges will need to be overcome on multiple fronts spanning supply chains, talent management, operations and technology.”

Putting up tariff barriers is one sure way to make sure that China wins while others — especially the US — are the biggest losers and left gasping on the side of the highway that leads to the future.

We have said many times here at CleanTechnica that the batteries in use in 2030 haven’t been invented yet. They will cost less and do more than any commercially available batteries of today and make the transition to an electricity-based economy a no-brainer. When it comes to electro-states, the future’s so bright, you gotta wear sunglasses — especially if you happen to be China.