Battery Electrodes Now Possible From Packing Peanuts

Packing peanuts: these pesky foam peanuts might just be the next big thing in energy technologyPacking peanuts: these pesky foam peanuts might just be the next big thing in energy technology

Finding a new use for waste products is a valuable avenue of research, both from an environmental and an economic standpoint. Brand new research reported this past weekend at the American Chemical Society Meeting has shown that packing peanuts – those pesky, statically charged foam nuggets that seem to end up everywhere after you've received fragile goods in the mail – can be transformed into electrodes for lithium ion batteries that actually perform better than many standard materials.

Lithium ion batteries are common in consumer electronics where they are popular thanks to their ability to store a large amount of energy in a relatively compact area as well as very slow charge loss when the battery is not in use. They are increasingly being investigated for further application in electric vehicles and aerospace technologies making advances in this field widely applicable. These batteries consist of three main components: a positive electrode (cathode), a negative electrode (anode) made up of a porous material, and an electrolyte. When charging, a voltage is applied by an external circuit causing the lithium ions migrate from the cathode to the anode where they become embedded in the pores of that electrode. Upon battery use or discharging, the ions carry current back through the electrolyte to the positive electrode. 

The typical porous anode material in lithium ion batteries is graphite due to its well-established ability to absorb and release lithium ions during charging and discharging cycles. Therefore, the first step in transforming packing peanuts to electrodes was to carbonize them by heating at 500 – 900 degrees Celsius for several hours. To further improve performance, a metal catalyst was added at the same time. The resultant charred polystyrene pieces were then ground up into a fine powder of carbon "microsheets". As compared with typical graphite electrodes, the carbonized microsheets allowed for faster battery charging due to their smaller size. They also offered increased energy storage capacity due to their greater porosity; essentially, the microsheet shapes provided more nooks and crannies for the lithium ions to occupy and vacate.

Scientific research can often seem inaccessible due to the years of education required, the expensive instrumentation employed or the dense terminology scientists seem to prefer. Reports like this one show that sometimes breakthroughs arise from the least complicated circumstances: a researcher just finishing a big move is faced with the dilemma of too many packing peanuts, and decides to cook them in the oven.