Researchers created freeze-thaw battery that freezes the energy for months to use it later without affecting its storage capacity
A team of engineers at Northwest National Laboratory (PNNL) developed a novel design for battery that hibernates to preserve its energy for months. The new freeze-thaw battery design locks its energy in for a long time period in order to use it later. As per the research published in the journal ScienceDirect on March 23, 2022, the battery freezes the energy without losing its storage capacity, and this development is a step forward to batteries that are used for seasonal storage, which saves energy in one season.
For this research the scientists used an energy storage technology called as molten-salt battery. Such batteries are being used for a very long time in different forms. As they cost very less and use materials that are commonly available, scientists are interested in these batteries for grid-scale storage solution for renewable energy. The team of scientists in this new research developed a temperature-based hibernating battery. This new design includes an aluminum anode and cathode made of nickel. These parts are submerged in a molten salt electrolyte having sulfur for addition capacity. The team heated the battery to 356˚ F to charge it where ions flow in the liquid electrolyte and produce chemical energy. Then, the team cooled the battery down to room temperature so the electrolytes are solidified and to freeze the ions in the place, which further locks the energy in until the battery us heated again for the energy to start flowing.
The scientists call this battery as freeze-thaw battery. The energy stored in this battery costs nearly US$23 per kWh, which would later be reduced to US$6 per kWh. As the prototype of this battery has size of a hockey puck, its density is 260 Wh per Kg. When tested, the battery was found to retain 92% of its capacity for 12 weeks.