EAS IX: Neil Johnson of Navitas on Battery Safety

Dean Sigler Electric Aircraft Components, Electric Powerplants, Sustainable Aviation 0 Comments

Neil Johnson of the Navitas Systems Advanced Solutions Group gave the gathering at the ninth annual Electric Aircraft Symposium an overview on battery reserve limits and gauging, and the methods necessary to address the different failure modes for lithium batteries, all of which could be problematic for electric aircraft. Navitas includes some legacy technology adapted from 123 Systems, typically 18650 format batteries, an 18-millimeter by 65-millimeter cylinder with active materials separated by a dialectric separator material in a “Tootsie Roll” configuration.  Some of the chemistries involved were developed for Formula 1 racers, and according to a talk given by Bill Dube’ and Eva Håkansson, are considerably more powerful than “conventional” lithium cells. According to Neil, the five billion cells out there now …

EAS IX: Mike Ricci Explains PWB, Safety

Dean Sigler Diesel Powerplants, Electric Powerplants, Sustainable Aviation 0 Comments

Dreamliner battery nightmares have troubled the dreams of electric flight for the past two years.  Michael Ricci, Vice President of Engineering with LaunchPoint Technologies, gave attendees at this year’s Electric Aircraft Symposium a crash course (pun intended) in the many types of failure modes electric aircraft face.  Luckily, he also provided ways to mitigate and eliminate those failure modes. He introduced a concept called “Propulsion by Wire” (PBW), the main thrust for electric aircraft and roughly akin to the commonly discussed “Fly by Wire” concept.  Asking what product specifications for electric propulsion will look like, he answered his own rhetorical question with the technical requirements for reasonable interaction, a useful user interface, airworthiness, and safety. Starting with the last issue …