Hemp is a versatile crop that can be used for industrial purposes such as food, clothing, and paper, but also with the new research, hemp can be used to create batteries that are more powerful than lithium and graphene.
Robert Murray Smith conducted this experiment and discussed it on his popular YouTube channel. He began the experiment by observing Volts by Amps curve of the hemp and lithium batteries. By his surprise, the power on the hemp cell had a value of 31 while the power of the lithium cell had a value of 4.
Smith claims that he hasn’t proven anything except that the end result of the experiment shows that the performance of the hemp cell is much better than the lithium cell.
This discovery isn’t new because in 2014 US researchers found that waste fibers from hemp crops called “shiv” transformed into ultrafast, supercapacitors that are better than graphene. Graphene is a synthetic carbon material that is bulletproof and lighter than foil. The only limit to using it is practicability. However, hemp can cost 1/1000 of the price of graphene.
Dr. Mitlin said that “People ask me: why hemp? I say, why not? We’re making graphene-like materials for a thousandth of the price – and we’re doing it with waste.”
In the experiment in 2014, Dr. David Mitlin of Clarkson University, New York, led the team that “cooked” leftover bast fiber, which is the inner bark of the plant that ends up in landfills, into carbon nanosheets. This process is called hydrothermal synthesis.
The fibers were later recycled into supercapacitors, which are energy storage devices that have changed the way we power electronics. Large reservoirs of energy are stored in conventional batteries and drip-feed, whereas supercapacitors rapidly discharge their entire load. This makes supercapacitors ideal for machines that require sharp bursts of power.
Mitlin adds that “you can do really interesting things with bio-waste”. With banana peels “you can turn them into a dense block of carbon – we call it pseudo-graphite – and that’s great for sodium-ion batteries. But if you look at hemp fiber its structure is the opposite – it makes sheets with a high surface area – and that’s very conducive to supercapacitors.”
When the bark is cooked, “you dissolve the lignin and the semicellulose, and it leaves these carbon nanosheets – a pseudo-graphene structure.” The resulting supercapacitors function at a high energy density and a wide range of temperatures.
The device has been ranked by a peer-reviewed journal paper as “on par with or better than commercial graphene-based devices.”
Mitlin explained that “They work down to 0C and display some of the best power-energy combinations reported in the literature for any carbon. For example, at a very high power density of 20 kW/kg (kilowatt per kilo) and temperatures of 20, 60, and 100C, the energy densities are 19, 34, and 40 Wh/kg (watt-hours per kilo) respectively.”
When they are fully assembled, the density of energy is 12 Wh/kg with a charge time of less than six seconds.
Alternet, a Texas-based electric motorcycle company, announced in 2018 that it would be joining forces with Mitlin to power motorcycles for its ReVolt Electric Motorbikes subsidiary.
Hemp is a versatile and valuable resource. As the crop is decriminalizing, many companies will start transitioning our planet to run on sustainable energy.