A renewable energy future will rely on cheap and scalable battery technologies. A promising option is an all-iron redox flow battery, which uses iron—an abundant, low-cost, and safe material. Battery performance depends on how iron ends up on the negative electrode during battery use. Uniform iron deposits are best, but this doesn't always take place.
Using neutron imaging, a team of TU/e researchers in collaboration with the Paul Scherrer Institute in Switzerland visualized the motion of metallic iron in an all-iron redox flow battery and tracked how the solid, gas, and liquid phases of iron form in real time.
Their results, published in the journal Nature Communications, can help the design and performance of future batteries.
If you peer inside a redox flow battery, you'll see fluids on the move, otherwise known as electrolytes. These electrolytes contain ions, which in the case of an all-iron redox flow battery (AIRFB) are iron ions. Movement of these ions influences how well the battery charges and discharges. Of particular significance is how iron coats the battery's negative electrode during use.
"This ultimately dictates battery performance," says Ph.D. researcher Marina Tabuyo-Martinez, a co-first author of the paper with Inmaculada Gimenez-Garcia. Both completed the work in the Electrochemical Materials and Systems group at the Department of Chemical Engineering at TU/e.
