When we think of batteries, lithium batteries immediately come to mind. After all, with new energy vehicles everywhere, the name "lithium battery" is practically a household name.
But have you noticed that batteries aren't just for cars? With the increasing use of clean energy sources like wind and solar power, a crucial question arises—how do we store the excess electricity generated during the day but not at night? This is where energy storage comes in. However, in the field of energy storage, lithium batteries are not a panacea.
Frankly speaking, the requirements for batteries in energy storage are completely different from those in automobiles. It doesn’t prioritize the density of stored energy (i.e., energy density), but it has very stringent requirements for safety, lifespan, and the number of charge-discharge cycles.
This is where flow batteries become more suitable than lithium batteries. You can think of a flow battery as a “flowing power bank.” Its active materials are all in the electrolyte, which circulates to complete charging and discharging, making it much more stable than lithium batteries.
A Potential Stock in the Energy Storage Market: Why Zinc-Bromine Batteries Are Gaining Popularity? There are many members in the flow battery family, with vanadium redox flow batteries being the most commercially viable. However, it has an unavoidable drawback—high cost. Vanadium is expensive, making large-scale use costly.
Zinc-bromine flow batteries, on the other hand, have long been considered a potential stock in the energy storage field, with a long list of advantages.
Let me tell you, zinc-bromine batteries were first developed by ExxonMobil in the United States, using zinc as the negative electrode and bromine as the positive electrode. The cost advantages of these two materials are too obvious: China is a major zinc-producing country, and zinc is only one-third the price of vanadium.
Bromine is even less of a concern; it’s abundant in the ocean, and the refining cost is negligible. As the second most commercially viable technology after vanadium redox flow batteries, its prospects in the energy storage field have long been promising.
More importantly, there’s safety. Zinc-bromine batteries use zinc bromide aqueous solution as the electrolyte, which is not only non-flammable but also inherently flame-retardant. Whether for home or factory use, safety is paramount, and zinc-bromine batteries excel in this regard.
However, it has previously been hampered by a fatal problem—its high corrosiveness.
Bromine and chlorine are in the same group of elements, so its corrosiveness is self-evident. Battery components are easily corroded, directly hindering its large-scale adoption.
Good news from the laboratory: a “corrosion-resistant coat” for the battery!
On December 19, 2025, good news finally arrived! A research team led by Professor Li Xianfeng at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, published a groundbreaking finding in the top journal *Nature Energy*, directly overcoming the corrosion problem of zinc-bromine batteries.
This removes the biggest obstacle to the large-scale application of zinc-bromine batteries.
Their method is particularly ingenious, essentially providing a “hiding place” for corrosive elemental bromine. Specifically, they added an amine compound with an electron-withdrawing group to the bromine electrolyte, acting as a “bromine scavenger.”
In this way, the highly corrosive elemental bromine produced during battery charging is converted into bromoamine compounds, reducing the concentration of elemental bromine in the solution to an extremely low level, approximately 7 mM.
The experimental data caused a sensation in the industry: even using inexpensive, less corrosion-resistant SPEEK membranes, the battery still operates stably.
Most importantly, before and after cycle testing, the battery’s key components, such as the current collector and electrodes, showed absolutely no signs of corrosion. This means that battery lifespan can be significantly extended, and maintenance costs can be reduced.
In fact, this isn’t the first time the Dalian Institute of Chemical Physics has led the way in the zinc-bromine battery field. Back in 2018, their 10kWh zinc-bromine single-flow battery demonstration system had already reached world-leading levels.
This technological breakthrough represents another step forward on top of their existing leadership, pushing the commercialization prospects of zinc-bromine batteries a significant step forward.
Accelerating Implementation: From Lab to Real Life
From another perspective, the success of a technology ultimately depends on its practical application.
The new energy storage industry is now rapidly expanding, and the industrialization of zinc-bromine batteries is progressing faster than many people expected. It’s no longer a “highbrow” technology in the laboratory, but is gradually entering our lives.
Besides residential use, grid-side applications have also yielded results. In May 2025, the nation’s first low-voltage distributed zinc-bromine flow battery energy storage device was successfully put into operation in Benxi, Liaoning.
This 50kW/200kWh device directly reduced the load rate of the local distribution transformer from 85% to 60%.
Some may not understand what load rate means. Simply put, the transformer was previously operating at near-overload capacity, making it prone to failure. Now, with the load rate reduced, operation is more stable, and there’s no longer any fear of overload outages during peak electricity demand.
Even more impressively, this device integrates AI technology, enabling it to proactively participate in the electricity market’s demand response. It discharges when the grid needs electricity and charges when there’s a surplus, alleviating power shortages and generating revenue for the operator.
In conclusion, the zinc-bromine battery’s breakthrough in overcoming corrosion is not just a small technological breakthrough, but further proof of our country’s leading position in the entire new energy system.
Now, we are not only advanced in photovoltaics, wind power, and new energy vehicles, but also in key supporting technologies like energy storage, having built a complete green energy chain.
Frankly speaking, electricity is the foundation of the AI era. In the future, many countries may be hampered by energy issues, but we have already paved the way through continuous technological breakthroughs.
As more energy storage technologies like zinc-bromine batteries are implemented, green electricity will be able to steadily support the development of the smart era, our energy resources will only become stronger, and our advantages in global energy competition will become more and more obvious.
