Vanadium flow batteries emerge as a promising solution for storing renewable energy, offering extended lifespans, elevated safety standards, and scalability.
Chinese scientists at the Dalian Institute of Chemical Physics, part of the Chinese Academy of Sciences, have unveiled a groundbreaking development in the field of large-scale energy storage—a new and powerful vanadium flow battery stack. This innovation could potentially reshape the landscape of renewable energy storage. Vanadium flow batteries have long been regarded as a promising technology for storing renewable energy due to their extended lifespans, high safety standards, and scalability. However, their widespread adoption has been hindered by the considerable initial costs associated with the technology.
The critical component of vanadium flow batteries is the stack, a series of cells responsible for converting chemical energy into electrical energy. The cost of the stack is heavily influenced by its power density, which is the ratio of power output to stack volume. The researchers at DICP have successfully designed a 70 kW-level stack, surpassing the current 30 kW-level stack in power by more than double. This achievement was made possible through the utilization of self-developed materials, including weldable porous composite membranes and weldable highly conductive bipolar plates.
The resultant stack boasts an impressive volume power density of 130 kW/m3, coupled with a 40% reduction in cost. Its other notable features include high energy efficiency exceeding 80% under different power conditions and stable performance after over 1,200 cycles, with only a minimal 1.7% energy efficiency decay. The researchers assert that their high-power density stack has the potential to double the power of a 20-foot container energy storage unit module from 250 kW to 500 kW without significantly increasing the size of power units or the cost of system-supporting facilities.
Professor Li Xianfeng, the leader of the research team, expressed optimism about the commercial prospects of this 70 kW-level stack, emphasizing its potential to drive the commercialization of vanadium flow batteries and enhance the integration of power units in energy systems. While further research and development are necessary to optimize performance and reduce costs, this achievement marks a significant step toward realizing the full potential of vanadium flow batteries in the quest for efficient and sustainable energy storage solutions.