Following this question posted on Aviation:SE:
which is related to a hovering board described on the vendor site:
I would like to assess the claim this device really exists. In particular I wonder if it is possible to use the batteries to deliver 200 kW as claimed. I'm not trying to evaluate the aerodynamic aspects.
I don't see what technology could be used other than Li-ion cells. Assuming this is true, would this solution be compatible with the claimed characteristics:
- Power delivered: 200 kW,
- Running time: 3 min for a 110 kg user, to 6 min for a 82 kg user,
- Charging time: 6 hours, reduced to 35 min using a docking station.
Taking into consideration the Li-ion characteristics with the knowledge of an electrical engineer, is there any aspect that would prevent this solution to work, e.g:
- Weight, volume of the batteries (the board measures 145×76×15 cm),
- Wires size (there is little room available in the box),
- Current for charging (is this feasible to charge in 35 min),
- Discharge time (would cells allow to be discharged in 3 to 6 min),
- Cost (replacement of batteries is offered at $6,840).
No speculation please, but known facts that would definitely contradict or support the possibility of the solution. For instance, I think these deductions are correct:
- For a 3 min hovering, with 200 kW, about 10 kWh are used.
- Due to specific energy and density for Li-ion, this means 40 kg and 14 dm3 for the batteries.
- Price of the batteries: With an optimistic 0.40 $ / Wh, this would be $4,000.
- Charging 10 kWh in half an hour requires a 20 kW charger.
- Assuming cos φ = 1, this would mean 91 A for 220V (well past what is usually found at home), and 5,000 A for the Li-ion cell voltage (this would require large wires that are not visible in the picture).