Messy Innards Make for a Better Lithium Ion Battery
Sometimes is pays off to be a little messy…espcially if you’re a lithium ion battery. Via Scientific American.
Inside a lithium-ion battery, you might not want to keep everything neat and tidy; a little bit of disorder may improve its performance, according to new research.
Engineers meticulously arrange materials in rigid patterns in typical lithium-ion cathodes and anodes, the idea being that a more structured arrangement yields a more efficient battery. In the pursuit of greater energy densities, better performance and longevity, designers are seeking ways to structure battery components more rigorously and at smaller scales.
Letting material layers blend or lose their shape often corresponds to weaker battery performance, a situation that arises as these devices age. The lithium ions have a harder time moving through the cathode and thereby deliver less energy.
“This understanding and experimental evidence has generally led battery scientists to overlook disordered materials,” explained Jinhyuk Lee, a research assistant in materials science and engineering at the Massachusetts Institute of Technology.
However, he found that in some circumstances, disruption could have performance benefits. Lee and his collaborators published their findings last week in the journal Science.
“In this paper, we found a particular composition that when it becomes disordered, it can still have a good performance,” said co-author Dong Su, a staff scientist in the electron microscopy group at Brookhaven National Laboratory.
Researchers used a blend of lithium, chromium and molybdenum for the cathode, initially alternating between lithium and transition metal oxide layers. After charging and discharging the battery a few times, they found the performance remained steady.
What made this battery design work so well with a disordered structure compared to previous designs was the presence of excess lithium. Conventional lithium-ion batteries use equal amounts of lithium and a given transition metal. With the new formula, the extra lithium finds its own path through the cathode, creating faster channels for the ion and delivering a more consistent performance.
Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.