New Spraying Technique Could Lead to More Powerful Batteries
A novel spraying technique could help make an experimental type of high-power battery a commercial reality, say scientists.
Researchers are working on a new type of high charge battery that involves carbon nanotubes, or microscopic rolls of carbon one-atom thick.
Currently, the method to produce the novel element in these batteries takes days to a week and requires constant dipping of tiny glass plates into diluted solutions of carbon nanotubes (CNT). A cycle of immersion in differently charged baths and rinsing takes 20-30 minutes per layer.
The final coating needs tens to hundreds of layers, and that can add up to "a lot of minutes," researcher Paula Hammond at Massachusetts Institute of Technology told TechNewsDaily.
A new technique for depositing the solution layer-by-layer cuts assembly time down to seconds if the glass is subjected to automated spraying rather than soaking.
"It's one to two minutes for the entire process," and could speed up battery production by a factor of 40 to 100, Hammond said.
The new CNT-containing battery can store more electrical charge than conventional batteries because its alternating layers create a dense, porous network of fibers that soaks up higher quantities of charged particles, or "ions," than the bulk metal or carbon materials used in other batteries.
In any battery, there are two terminals, called electrodes, between which charged particles flow.
Higher numbers of particles flowing and faster transfer times alike make for greater power. The sponge-like microscopic structure of the carbon-nanotube film stores more energy than conventional electrodes. Because it also has a higher surface area, this energy can be rapidly retrieved and replenished.
Power put out by batteries outfitted with a CNT-containing electrode exceeds current models by a factor of ten, researchers said in statement.
"High power batteries have been elusive in the field," Hammond said. Conventional batteries can store large amounts of energy, but can only release that energy slowly over time because the chemical reactions involved are relatively slow.
Batteries that can rapidly absorb and transfer large amounts of energy quickly would make technologies like electric cars feasible because of their extended lifetime and dramatically shortened recharging time.
When manufactured in high volumes, such batteries would also allow for faster data retrieval and higher performance memory storage in laptops and other devices.