Lawrence Livermore National Laboratory (LLNL) researchers, along with a team from UC Santa Cruz (UCSC), have recently devised a method for doubling the performance of 3D-printed graphene-based supercapacitors.
The method, which involves sandwiching lithium ion and perchlorate ion between layers of graphene in aerogel electrodes, substantially improved the capacity of the electrodes while still maintaining the devices’ excellent rate capability, the researchers discovered.
“This is a unique method that significantly raises the performance of our previous graphene aerogel supercapacitors,” said LLNL engineer and paper co-author Cheng Zhu. “We’ve modified the devices and found the best recipe.”
LLNL researchers provided the UCSC team with the 3-D-printed graphene aerogel electrodes built using a direct ink writing process. Graphene-based materials are increasingly being used in supercapacitors because of their ultra-large surface area and excellent conductivity. The method involves two ion-intercalation steps (lithium-ion intercalation and perchlorate-ion intercalation), followed by hydrolysis of perchlorate ion intercalation compounds.
Zhu said the findings are the next step in creating more complex architectures using aerogels, enabling more powerful supercapacitors that could someday be used in custom-built electronics. “In the future, I think every device will be customized, so you need the unique architecture or shape (for the supercapacitor),” Zhu said. “If you can 3-D print it, you can make any shape you want. In the future, everyone could design their own iPhone.”