Leaf vein structure might help improve battery life

The vein structure in leaves could help improve performance of rechargeable batteries, claim scientists.

A team of scientists from China, the UK, US and Belgium designed a porous material that utilises vascular structures similar to those found in leaf veins. The porous structure could make energy transfer more efficient.

The material could improve battery life while optimising the charge and discharge process, and relieving stresses within the battery electrodes. This material could be used for high performance gas sensing or for catalysis to break down organic pollutants in water.

The team designed the material mimicking natural structures that follow the Murray's Law. According to the law, the network of pores in a biological system is interconnected in a way to facilitate the transfer of liquids.

The team was led by Bao-Lian Su from University of Cambridge, who adapted Murray's Law to develop what is termed as the first-ever synthetic Murray material and applied it to photocatalysis, gas sensing, and lithium ion battery electrodes.

Su explained: "This study demonstrates that by adapting Murray's Law from biology and applying it to chemistry, the performance of materials can be improved significantly. The adaptation could benefit a wide range of porous materials and improve functional ceramics and nano-metals used for energy and environmental applications.

"The introduction of the concept of Murray's Law to industrial processes could revolutionize the design of reactors with highly enhanced efficiency, minimum energy, time, and raw material consumption for a sustainable future," he said.

The team claims its Murray material, which was made using zinc oxide (ZnO) nanoparticles, can significantly improve the long term stability and fast charge/discharge capability of lithium-ion batteries. The material also led to capacity improvement up to 25 times in these batteries compared to graphite material used in current lithium-ion battery electrodes.

Researchers also found that the pores also reduce the stresses in these electrodes during the charge/discharge process, which in turn could result in a longer battery life.

Tawfique Hasan, of the Cambridge Graphene Centre, who is a part of the University's Department of Engineering, said, "This very first demonstration of a Murray material fabrication process is incredibly simple and is entirely driven by the nanoparticle self-assembly. Large scale manufacturability of this porous material is possible, making it an exciting, enabling technology, with potential impact across many applications."

The study is published in the journal Nature Communications.