A number of companies are developing electric power plants for aircraft, basically powered gliders and small ultralight aircraft. In most of these designs the power plant is of secondary importance and the aircraft can fly, or better glide, considerable distances without an engine purely by its basic properties.
Developments are in progress to electrify some every day general aviation class aircraft or even new designs. Because of many limitations to overcome, large scale applications will not come any time soon. The main problem is energy storage: liquid fuel (AVgas or Jet fuel) has the highest energy density per weight, which is very hard to beat, except for nuclear power plants. This will limit the range of any aircraft trying to fly any considerable amount of time or distance with a worthwhile payload.
Storing electric energy is still, after decades of using lead acid batteries, in its infancy. And may never get to the point where is equals the density and ease of refilling compared to liquid fuels. Although some companies make progress they are still looking for the holy grail of batteries.
Excerpt from the application note:
OXIS Lithium Sulfur (Li-S) chemistry is inherently safe, due to the lithium sulfide passivation layer and its non-flammable electrolyte (flash point above 140°C). OXIS technology can easily handle abuse conditions including nail penetration, short circuit and overcharge with no adverse reaction. This compares to Lithium Ion (Li-ion) which has a poor reputation for safety.
OXIS cells have now achieved an excellent cycle life: in tests, we have achieved over 1,000 cycles before capacity reduces to 80%. In our latest cells, we are targeting 2,000 cycles.
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