We’re using conventional silicon solar cells, rather than the GaAs cells used by Airbus. We give up some efficiency by doing this, but it keeps costs far lower - which we think is key to iterating quickly, and opening up some of the market use cases.
Similarly, we’re sticking with conventional battery chemistries (Lithium Ion). Battery energy density is by far the biggest driver for this technology - in the past decade we’ve seen huge advancements in battery tech, which is one of the reasons this technology is now possible. As you identify, cycle life is a key challenge and what will limit the aircraft’s endurance.