Lithium-ion batteries, for the moment, are the best solution for lightweight [relatively] and reliable portable power, but various other battery formulations, such as lithium sulfur, could be a better option.
As we know, lithium-ion batteries are not without their problems. The very thing that makes lithium-ion batteries so effective, the liquid electrolyte, also makes them flammable. Granted, with enough precautions, we don’t expect our portable electronic devices and electric vehicles to burst into flame, but recent events seem to indicate otherwise, such as Boeing 787 Dreamliner’s lithium-ion backup battery packs.
Oak Ridge National Laboratory [ORNL] has developed a lithium sulfur battery that is much safer. The electrolyte in this battery is solid and stable and non-flammable. In addition, the capacity of ORNL’s lithium sulfur battery is four times that of a comparable lithium-ion battery, even after 300 cycles. Sulfur is also far less expensive than lithium, which could help to drive down the cost of rechargeable batteries using ORNL’s lithium sulfur formulation in the future.
Some forms of lithium sulfur batteries are already in use in solar-powered aircraft and other applications. Given that lithium sulfur is shown to be more more dense and less expensive to produce, it shouldn’t be long before we see new technology showing up in everything from personal electronic devices to electric vehicle traction batteries. ORNL is filing patents on its solid lithium polysulfidophosphate cathode, but isn’t the first to develop a prototype.
“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,” said , lead author on the ORNL study.