Nature inspired design of super-capacitors
26th February, 2018: Super-capacitors are rechargeable energy
storage devices that deliver more power for their size than conventional
batteries. They find application, wherever rapid and repeating charging/discharging
cycles are required, like in electric cars, buses, trains, cranes and
elevators. They are used to implement regenerative braking, short-term energy
storage or burst-mode power delivery.
In a path-breaking discovery, researchers of University of California, Los Angeles (UCLA) have developed designed a super-efficient and long-lasting electrode for super-capacitors. The new charging device developed by UCLA is more than 10 times more efficient than the existing designs. The results of their study are recently published in the journal Nature Communications.
Engineers developed a branch-and- leaves design for the purpose. The branches were made of arrays of carbon nano-tubes, emulating branches of a tree and the sharp-edged petal-like structures were made of graphene, consisting of a single layer of carbon atoms arranged in an hexagonal lattice.
The efficiency of super-capacitors depends on the efficiency of their electrodes to transfer ions during the charging/discharging process. The more ions they can exchange, the faster they can deliver power. To create optimal condition for ion transfer, the UCLA engineers wanted to maximize its surface area of the electrodes. The idea for implementing the same, they got from the nature: from t he structure of a tree with its branch-and- leaves structure, which is arranged in such a way that it optimizes the ability of a tree to absorb ample amounts of carbon dioxide for photosynthesis.
“We often find inspiration in nature, and plants have discovered the best way to absorb chemicals such as carbon dioxide from their environment,” said Tim Fisher, the leader of the research team.
The superior performance of the newly developed super-capacitors remained unaffected by acidic conditions or high temperature.