Environment

Scientists convert tamarind waste into energy storage material for EVs

Scientists convert tamarind wa...
Asst. Prof. (Steve) Cuong Dang with a handful of tamarind pod shell fragments, which were converted into carbon nanosheets via a process known as pyrolysis
Asst. Prof. (Steve) Cuong Dang with a handful of tamarind pod shell fragments, which were converted into carbon nanosheets via a process known as pyrolysis
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Asst. Prof. (Steve) Cuong Dang with a handful of tamarind pod shell fragments, which were converted into carbon nanosheets via a process known as pyrolysis
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Asst. Prof. (Steve) Cuong Dang with a handful of tamarind pod shell fragments, which were converted into carbon nanosheets via a process known as pyrolysis
The bulky shells of tamarind fruit pods take up a disproportionately large amount of space in landfills
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The bulky shells of tamarind fruit pods take up a disproportionately large amount of space in landfills

Along with their batteries, many electric cars now utilize supercapacitors for tasks such as quickly delivering power while accelerating. Thanks to new research, a key component of such devices could soon be made from waste tamarind shells.

Although not particularly common in places like North America and Europe, tamarind fruit is consumed in great quantities in Asia and other regions. And while the shells of its pods are compostable, they're most often just dumped in landfills.

Seeking a high-value use for the shells, an international team of scientists set about utilizing them as the source material for carbon nanosheets, which store the electrical charge within supercapacitors. The project was led by Singapore's Nanyang Technological University, and also involved researchers from India's Alagappa University and the Western Norway University of Applied Sciences.

The bulky shells of tamarind fruit pods take up a disproportionately large amount of space in landfills
The bulky shells of tamarind fruit pods take up a disproportionately large amount of space in landfills

The scientists started by washing tamarind shells that were obtained as waste from the food industry, after which the shells were dried at a temperature of 100 ºC (212 ºF) for about six hours. Next, the washed and dried shells were ground into a powder that was baked in a furnace at 700 to 900 ºC (1,292 to 1,652 ºF) for 150 minutes, in the absence of oxygen.

Doing so converted the powder into carbon nanosheets, which are ultra-thin layers of carbon. The tamarind shells were particularly well-suited to the task, as they are both rich in carbon and porous in structure – that porosity increases the surface area of the carbon in the nanosheets, allowing it to store more electricity.

Additionally, the tamarind carbon nanosheets exhibited good electrical conductivity and thermal stability. What's more, the production process was less energy-intensive than the procedure required for making nanosheets out of commonly used hemp fibers. In that process, the fibers initially have to heated at over 180 ºC (356 ºF) for 24 hours, after which they're baked in a furnace like the tamarind pods.

That said, the researchers are now trying to reduce the energy requirements of their technique, along with investigating other ways of making it more eco-friendly. They're also hoping to scale the technology up for commercial-level production of the carbon nanosheets.

A paper on the study, which is being led by Nanyang's Asst. Prof. (Steve) Cuong Dang, was recently published in the journal Chemosphere.

Source: Nanyang Technological University

3 comments
3 comments
paul314
Is there any fruit/vegetable waste that can't be converted into porous carbon at this point?
jerryd
Only incompetent engineers or scam artist would put SCs in an EV. They are large, heavy, have no capacity and very expensive. They to be frank, are a scam.
Note Tesla own's the largest SC company, Maxwell, and can't get anyone to buy the SC part.
SC are 30x heavier, 30x more space and 30x more costly/kwh. Fact is modern Li-ion cells can put out and suck up the power pulses without a problem at a fraction of the cost.
Anytime you hear Supercap, UltraCap, run as likely a scam..
Karmudjun
Nice article Ben - I especially liked the comparison between the hemp and the tamarind rind processing energy/time requirements.
Since the development of super or ultracapacitors, there have been amazing breakthroughs - this is yet another incremental one.

And yet we have to read a libelous mis-information regarding SC's. Thanks for your off the chart misguidance Jerryd!
Yes, SC's remain 30-40x as costly as the cheapest lithium ion power packs. They are equivalent in weight to metal hydride batteries for the equivalent (which is not strictly equivalent, only comparative), and their ability to "dump" energy much faster than batteries while avoiding the battery high discharge physical & chemical issues IS NOT A SCAM. There are very very few lithium ion battery cells that can dump energy and recharge quickly that have the lifespan of SC's.
In the era of Trumpster - you have just fake-fact - bombed NewAtlas. So please, anytime you hear SC - turn away. Breakthroughs continue in litium ion technology and super caps - one day you will be right but today is not that day!