Scientists at Oak Ridge National Laboratory have come up with a critical component meant for a new type of low-cost stationary battery system. It utilizes common materials and is designed for electricity and energy storage on a grid-scale. Massive and economical storage systems for electricity is useful for a nation’s grid in many ways. They help to distribute loads between off-peak and peak times; provide power during outages; store solar and wind electricity which fluctuate; and allow superfast charging of electric vehicles.
The grid depends mainly on hydropower facilities for energy storage, even though stationary systems leveraging batteries of lithium-ion are rising by the day. One drawback: Lithium costs a lot and is sourced from nations outside the U.S.
The Membrane Can Store Electricity on Grid Scale at Low Cost
Many utility companies are testing the RFB (redox flow battery) systems which are a hybrid of fuel cell and conventional battery. RFB are perfect for the grid owing to their durability and scalability. They also require less time for response. But, RFBs tested these days mainly bank upon an aqueous system, and this serves to reduce the amount of electricity stored. This is also known as energy density.
A flow battery which is non-aqueous and built from commonplace cheap materials instead of water is capable of storing greater amounts of power in smaller volumes. This has been a top priority for battery scientists. A hiccup however is developing a membrane to effectively separate the positive and negative electrodes while enabling ion transfer.
The team of scientists are now focused on the membrane that could increase the density of energy. The membrane is being made from cheap polymer, polyethylene oxide (PEO). With the addition of plasticizer called tetraethylene glycol dimethyl, its conductivity gets increased manifold.