Let me explain.
A Li-ion battery is composed of three parts: an anode, a cathode and an electrolyte. In a Li-ion battery an electrolyte is dissolved in a solvent to release ions that transport a charge between the anode and the cathode. As a charge bounces between the anode and cathode, chemical energy is turned to electrical energy.
But, here’s the catch. The electrolyte, the medium for the charge, is liquid and therefore causes the anode and cathode to corrode and breakdown prematurely.
However, all of that might be about to change. According to Chengdu Liang, the Li-S battery team lead, "Our approach is a complete change from the current battery concept of two electrodes joined by a liquid electrolyte, which has been used over the last 150 to 200 years,"
The Oak Ridge team’s breakthrough occurred when they found a way to synthesize a new sulfur rich material which can conduct ions as well as Li-ion batteries. Combining their new, solid lithium polysulfidophosphate electrolyte with a solid anode and a solid cathode allowed Liang and his team to create a more energy dense, completely solid battery.
"Our battery design has real potential to reduce cost, increase energy density and improve safety compared with existing lithium-ion technologies." Said Liang.
While still in the early phases of development the ORNL team has confirmed that after 300 charge cycles at 140F (60C) their new battery can maintain a capacity of 1200 miliamp-hours (mAh). Add to this performance the fact that Li-Sulfur batteries conduct around half of the voltage of their Li-Ion brothers and you get a four-fold increase in energy density.
Liang’s team hopes that their technology can progress quickly from their demonstration to the lab and then to the commercial world. If it can, the devices of tomorrow will likely be able to handle the complex tasks we need them to perform with plenty of power to spare.
Image Courtesy of ORNL