Yes, and it's a bet they will probably lose, if they really need 500 Wh/kg in three years time. Their battery graph is a fairytale at best.
The current state-of-the-art batteries that researchers build in laboratories that last 10-20 cycles can put out about 400 Wh/kg. You're simply not going to achieve first a 20% improvement over that, then a development of the tech to increase lifetime to something useable, and then scaling that to widespread commercial availability, within three years time.
If we speak about what's available in laboratories, Lithium–sulfur battery gives around 550 Wh/kg with up to 1500 charge-discharge cycles ([1]). Not available commercially, but there are a few companies that try to commercialize them ([2], [3], [4]).
I would not bet that these batteries arrive fast enough to save Lillium.
Yeah, I'm kind of assuming Li-S batteries won't work out. Sony announced in 2015 they were going to have commercial production in 2020. No news since then. Many others in that field have gone into bankruptcy, including one of those you link to.
Agree their chart is a fairytale based on current chemistries. It's basically a bet on commercially viable solid state batteries, which are targeting somewhere in that 500 Wh/kg range, but are probably a couple more years out than Lilium needs. I guess they could drop their viable range quite a bit at the start to compensate...
The current state-of-the-art batteries that researchers build in laboratories that last 10-20 cycles can put out about 400 Wh/kg. You're simply not going to achieve first a 20% improvement over that, then a development of the tech to increase lifetime to something useable, and then scaling that to widespread commercial availability, within three years time.