Controlling the shape of nanomaterials, for example by forming nano swiss roll like structures allows batteries with enhanced performance to be developed.
Li-ion batteries power many of our portable electronic devices such as mobile phones and laptops. From personal experience we know that our devices are quick to run out of juice and slow to be charged again.
The most common material used in commercial batteries today is graphite. However, this material has a limited capacity to store charge and researchers are investigating alternative materials which can hold more charge.
In order to improve battery performance, novel nanomaterials, which have features 10 000 times smaller than the width of a human hair and boast many advantages such as high surface area, are being used as alternatives to graphite.
Often nanomaterials with different properties are combined together in hybrids to take advantage of the benefits of each material. In these composites, an active material which holds the charge is combined with a support material which can improve the electrical performance.
The recent discovery of the nanomaterial graphene, a single layer of carbon atoms arranged in a hexagonal lattice with extraordinary electrical and mechanical properties, has encouraged many researchers to use this material in batteries.
Graphene’s properties such as high surface area, high conductivity, chemical and thermal stability and flexibility make it an ideal material for use in energy storage applications, especially in composites with active materials.
In my research I am investigating how graphene can be combined with metal oxides in hybrid structures. These hybrid structures can take many forms. The metal oxides can be anchored on top of the graphene sheet, or they can form a sandwich like structure with alternating layers of metal oxide and graphene.
In my research I have synthesised nano swiss rolls made of metal oxide rods wrapped by graphene. These swiss rolls are then aligned parallel to one another into tightly packed arrays. This results in more material in the same volume of space, and the alignment allows the charges to travel more easily in the battery.
Controlling the shape of the hybrid material, for example by forming nano swiss roll like structures, and the orientation by aligning, allows batteries with enhanced performance to be developed.
Mohammad Hadi Modarres
NanoDTC PhD Student Cohort 2013
Department of Engineering
Cover Image- Credit- Pioneer Woman