The #electric #aviation industry has publicly downplayed the challenges associated with certifying large #lithium propulsion #batteries, but it’s been a topic of intense negotiation behind the scenes. That's why a milestone announced this week by Swiss battery maker #H55 is so meaningful: it shows a manufacturer and regulator agreeing on the specific tests required to demonstrate that a large propulsion battery is safe for #flight. Full story in The Air Current: https://theaircurrent.com/aircraft-development/solar-impulse-h55-battery-certification-hurdle-electric-aviation/