Researchers from Chalmers University of Technology, Sweden, have outlined a new concept for rechargeable cement-based batteries.
Dr Emma Zhang, formerly of the university, joined Professor Luping Tang’s research group to search for the building materials to be used in future construction projects.
They now claim to have succeeded in developing a world-first concept for a rechargeable cement-based battery.
The concept involves a cement-based mixture, with small amounts of short carbon fibres added to increase the conductivity and flexural toughness.
Then, embedded within the mixture is a metal-coated carbon fibre mesh – iron for the anode, and nickel for the cathode.
Commenting on the concept, Zhang said: “Results from earlier studies investigating concrete battery technology showed very low performance, so we realised we had to think out of the box, to come up with another way to produce the electrode.
“This particular idea that we have developed – which is also rechargeable – has never been explored before.
“Now we have proof of concept at lab scale.”
The pair’s research has produced a rechargeable cement-based battery containing an average energy density of 7 Watthours per square metre.
Energy density is used to express the capacity of the battery, and a modest estimate is that the performance of the new Chalmers battery could be more than 10 times better than earlier attempts at concrete batteries.
When compared to commercial batteries, the energy density is still low; however, the researchers say this limitation could be overcome by the huge volume at which the battery could be constructed when used in buildings.
Zhang said: “It could also be coupled with solar cell panels, for example, to provide electricity and become the energy source for monitoring systems in highways or bridges, where sensors operated by a concrete battery could detect cracking or corrosion.
“We have a vision that in the future this technology could allow for whole sections of multi-storey buildings made of functional concrete.
“Considering that any concrete surface could have a layer of this electrode embedded, we are talking about enormous volumes of functional concrete.”
Tang added: “We are convinced this concept makes for a great contribution to allowing future building materials to have additional functions such as renewable energy sources.”
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