Electrified wingsuit from BMW reaches 186MPH on first flight

Lithium-based batteries (and associated tech) are to the 21st century what the internal combustion engine was to the 20th century and what the steam engine was to the 19th century.

There’s a ~90% chance you’re using a device powered by a lithium chemistry battery to read this right now (laptop or tablet or phone). The smartphone alone (enabled by lithium based batteries) has transformed the world. Lithium-based batteries have impacted public health & healthcare (e-cigs vs conventional, medical devices like insulin pump, etc), micromobility (e-scooters, e-bikes, electric wheelchairs, etc), countless accessories (smart watches, smart speakers, wireless earbuds), grid storage, electric cars, electric buses, electric trucks, electric ferries, electric rocket pumps (RocketLab), satellites, submarines, civil drones (like Zipline), and a whole bunch of things that have not yet been invented and perhaps require improved chemistry like lithium metal anode or lithium sulfur or eventually lithium-air (enabling long-haul electric flight, even supersonic flight).

For things like this article described, it will enable more expansion of form factors and reduce costs. Jet suits have been done before but equivalently-specked electric motors are much cheaper than the small, micro turbines used for projects like this. And micro turbines have such atrocious efficiency (about 4.4% for hobby turbine engines... meaning their fuel supply only has a useful specific energy of about 1.9MJ/kg or 525Wh/kg, compared to 0.5 MJ/kg for high-C-rate LiPo, 1MJ/kg for really good production Li-ion and 2MJ/kg for low C rate lithium metal anode cells and lithium sulfur) that after another few decades of battery chemistry improvement, electric microturbines not only will have punchier power but also longer duration.

There’s a ton of undeveloped opportunities out there that will be enabled by the efficiency, convenience, low-cost, high reliability, and oxygen-independence of lithium chemistry batteries.

An electric ducted fan (EDF) is highly inefficient, had they put similar wattage through a gearbox to say a folding prop, efficiency may have doubled (albeit an admittedly more onerous form factor). This is just the beginning of electric assist single passenger flight!

Reference: plenty of experience pushing 8KW+ through 2KG RC gliders (F5B) and far slower EDF models.

Lithium ion cannot output enough (low C) to make this feasible (yet). Much more likely using Li-Po cells, which are far more adept at emptying themselves at high load—but thermal runaway (eg insanely hot fires) is all too real with Li-Po, though less so today than say 6 years ago!

The periodic table is limited. Of all metals, lithium is the lightest. It also has the highest mass-specific conductivity and the highest chemical specific energy of all the metals.

Hydrogen is not a solid or a liquid at room temperature and is also too volumetrically in-dense.

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