New battery can be charged within seconds
NEW YORK: Scientists have developed a novel self-assembling battery device that can be recharged within seconds and could power mobile devices of the future.
Researchers from Cornell University in the US created a new battery architecture to address the demands for energy storage devices that can be charged faster.
Instead of having the batteries’ anode and cathode on either side of a nonconducting separator, they intertwined the components in a self-assembling, 3D gyroidal structure, with thousands of nanoscale pores filled with the elements necessary for energy storage and delivery.
“This three-dimensional architecture basically eliminates all losses from dead volume in your device,” said Ulrich Wiesner, a professor at Cornell.
“More importantly, shrinking the dimensions of these interpenetrated domains down to the nanoscale, as we did, gives you orders of magnitude higher power density. In other words, you can access the energy in much shorter times than what’s usually done with conventional battery architectures,” said Wiesner.
Due to the dimensions of the battery’s elements being shrunk down to the nanoscale, “by the time you put your cable into the socket, in seconds, perhaps even faster, the battery would be charged,” he said.
The architecture for this concept is based on block copolymer self-assembly, which the Wiesner group has employed for years in other devices, including a gyroidal solar cell and a gyroidal superconductor.
Joerg Werner, lead author of the study published in the journal Energy and Environmental Science, had experimented with self-assembling photonic devices, and wondered if the same principles could be applied to carbon materials for energy storage.
The gyroidal thin films of carbon - the battery’s anode, generated by block copolymer self-assembly - featured thousands of periodic pores on the order of 40 nanometres wide.
These pores were then coated with a 10 nm-thick, electronically insulating but ion-conducting separator through electropolymerisation, which by the very nature of the process produced a pinhole-free separation layer.
Defects like holes in the separator can lead to catastrophic failure giving rise to fires in mobile devices such as cellphones and laptops.
The next step is the addition of the cathode material - in this case, sulphur - in an amount that does not fill the remainder of the pores.
Since sulphur can accept electrons but does not conduct electricity, the final step is backfilling with an electronically conducting polymer - known as PEDOT.
The group is still perfecting the technique, but applied for patent protection on the proof-of-concept work.
Novel robotic system can grow mini human organs
WASHINGTON: Scientists have developed an automated robotic system that can rapidly produce mini human organs required for medical research and drug testing.
The traditional way to grow cells for biomedical research is to culture them as flat, two-dimensional sheets, which are overly simplistic.
In recent years, researchers have been increasingly successful in growing stem cells into more complex, 3D structures called mini-organs or organoids.
These resemble rudimentary organs and in many ways behave similarly. While these properties make organoids ideal for biomedical research, they also pose a challenge for mass production.
The ability to mass produce organoids is the most exciting potential applications of the new robotic technology, according to the developers.
In a study published in the journal Cell Stem Cell, researchers from University of Washington in the US used a robotic system to automate the procedure for growing stem cells into organoids.
Although similar approaches have been successful with adult stem cells, this is the first report of successfully automating the manufacture of organoids from pluripotent stem cells. That cell type is versatile and capable of becoming any type of organ.
In this process, the liquid-handling robots introduced the stem cells into plates that contained as many as 384 miniature wells each, and then coaxed them to turn into kidney organoids over 21 days.
Each little microwell typically contained ten or more organoids, and each plate contained thousands of organoids. With a speed that would have impressed Henry Ford’s car assembly line, the robots could produce many plates in a fraction of the time.
“Ordinarily, just setting up an experiment of this magnitude would take a researcher all day, while the robot can do it in 20 minutes,” said Benjamin Freedman, an assistant professor at UW.
“On top of that, the robot doesn’t get tired and make mistakes. For repetitive, tedious tasks like this, robots do a better job than humans,” he said.
The researchers further trained robots to process and analyse the organoids they produced. They used an automated, cutting-edge technique called single cell RNA sequencing to identify all the different types of cells found in the organoids.
“We established that these organoids do resemble developing kidneys, but also that they contain non-kidney cells that had not previously been characterized in these cultures,” said Jennifer Harder, an assistant professor at the University of Michigan in the US.
“These findings give us a better idea of the nature of these organoids and provide a baseline from which we can make improvements,” Freedman said.
The researchers discovered a way to greatly expand the number of blood vessel cells in their organoids to make them more like real kidneys.
They also used their new technique to search for drugs that could affect disease. In one of these experiments, they produced organoids with mutations that cause polycystic kidney disease, a common, inherited condition that affects one in 600 people worldwide and often leads to kidney failure.