By Dalian Institute of Chemical Physics, Chinese Academy Sciences January 22, 202470 kW-level vanadium circulation battery stack. Credit: DICPA new 70 kW-level vanadium flow battery stack, developed by researchers, doubles energy storage capacity without increasing costs, marking a considerable leap in battery technology.Recently, a research team led by Prof. Xianfeng Li from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) established a 70 kW-level high power density vanadium circulation battery stack. Compared to the present 30kW-level stack, this stack has a volume power density of 130kW/m3, and the cost is reduced by 40%. Cost-Effective Energy Storage SolutionVanadium flow batteries are one of the favored technologies for massive energy storage. At present, the preliminary financial investment of vanadium flow batteries is relatively high.Stack is the core element of a vanadium circulation battery. The power density identifies the cost of the stack. The greater the power density is, the smaller the stack volume is, resulting in lower cost under the very same power output conditions.Innovations in Battery DesignBased on self-developed extremely selective weldable permeable composite membranes and weldable extremely conductive bipolar plates, Prof. Lis team established a 70kW-level stack, utilizing a brief circulation course, an ultra-thin battery structure, and low flow resistance and high circulation harmony flow channels.The energy performance of this stack is 81.0% under 70kW rated power charge and discharge conditions, and the energy performance is 82.1% under 60kW constant power charge and discharge conditions, In addition, the stack operates stably after more than 1,200 cycles, with just 1.7% energy effectiveness decay.Scaling Up Energy Storage CapacityBy using this stack, a 20-foot container energy storage system module can be upgraded from 250kW to 500kW without greatly increasing the size of power units and the cost of system-supporting centers.”This 70kW-level stack can promote the commercialization of vanadium flow batteries. We think that the advancement of this stack will enhance the combination of power systems in energy,” stated Prof. Li.
