A new battery design could enable more affordable long-term energy storage, a press release from Imperial College London reveals.
Imperial’s team of engineers and chemists have developed a dual-membranes polysulfide air redox flow battery (PSA RFB).
This dual-membrane design offers a solution to some of the problems with PSA RFB, which means it can be used to store excess renewable energy for long periods of time.
The researchers, who published their findings in the journal Nature Communications, detail how they were looking for an alternative to the vanadium electrolyte, used in conventional redox current batteries, this type of battery. are often expensive and are mainly of Chinese or Russian origin.
First, they decided to use liquid, polysulphide, as the electrolyte, and gas, air, as other. However, their polysulfide air battery is limited by the fact that there is no membrane that can allow chemical reactions while also preventing the liquid electrolyte from passing through to another part of the cell.
“If the polysulfide crosses over into the air side, then you definitely lose material from one side, which reduces reaction taking area there and inhibits the interest of the catalyst on other,” stated Imperial College`s Dr. Mengzheng Ouyang, who worked at the study. “This reduces the overall performance of the battery – so it turned into a hassle we had to solve.”
Alternative approach to long-term energy storage
The researchers have developed an alternative method, which uses two membranes to separate the polysulfide and the air, containing a sodium hydroxide solution between the two parts of the cell. All materials are cheap and widely available, and the team says there’s still room to experiment to find even cheaper materials that can do the same job.
In their experiments, the Imperial team found that their polysulfide redox flow cell provides up to 5.8 milliwatts per square centimeter, while costing energy – the price of the material. data versus stored energy – which is about $2.50 per kilowatt hour. . The cost of electricity – the ratio of charge and discharge to the price of materials – is about $1,600 per kilowatt. Although this level is too high for long-term storage, the researchers say they believe they will be able to significantly improve energy costs.
Professor Nigel Brandon, who also worked on the project, said: “To make large-scale storage cost-effective, relatively modest performance improvements are needed. This can be done “by modifying the catalyst to increase its activity or by further improving the membranes used”.
The work of the Imperial team addresses the urgent need for new forms of energy storage as the world enters the era of renewable energy, according to the latest IPCC report, which warns of dire consequences if Necessary measures are not taken to greatly reduce humanity global carbon emissions.