One of the bottlenecks in widespread implementation of sustainable energy technologies are highly efficient energy storage systems. Lithium-ion batteries (LIBs) are the prevailing solution for today’s electronic devices, from consumer gadgets to medical devices, electric vehicles, even satellites. The main reason for the domination of LIB technology in many application areas is that it has the highest electrical storage capacity with respect to its weight.
LIBs generally contain an energy capacity of 100â200 Wh/kg. This allows most electric cars to travel upwards of 300-400 kilometers on a single change. However, despite the high energy density of LIBs compared to other kinds of batteries, they are still around a hundred times less energy dense than gasoline (which contains 12700 Wh/kg by mass or 8760 Wh/L by volume). That means that gasoline-powered engines are gaining higher thermal efficiencies, allowing for fuel efficiencies upwards of 6-7 L/100km. On a 60-liter tank, this allows for more than 800-1000 km of range, easily doubling, or even tripling that of the average electric car.
Although LIBs are continuing to achieve higher energy densities, various research studies are indicating that max theoretical energy limits (estimated at 400-500 Wh/kg) are in sight.
Since its first demonstration in 2004, the large-scale commercial production of graphene has proven difficult and costly (‘large scale’ usually defined as weights more than 200 mg or films larger than 200 cm2). For instance, at an estimated cost of $50 000 to $200 000 per ton for graphene powders and $45 000 to $100 000 per m2 of graphene film, industrial production methods and costs are restraining graphene utility.
Lire la suitePerovskite solar cells (PSCs) are promising solar technologies. Although low-cost wet processing has shown advantages in small-area PSC fabrication, the preparation of uniform charge transport layers with thickness of several nanometers from solution for meter-sized large area products is still challenging.
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