Ouch. The whole airplane only costs $200 million. The retrofit kit takes 5 days to install. This includes two 1/8th inch thick stainless steel fireproof battery boxes, two brand new batteries, two jazzier microprocessor controlled battery chargers that monitor the batteries while charging and light up warning lights in the cockpit when they detect a problem.
The new batteries have more insulation between cells to prevent/retard one runaway cell from setting off the other 7 cells in the battery. These are 32 volt batteries made up from eight 4 volt lithium cells all packed into a single battery enclosure. They believe (they don't know for sure) that something goes wrong in a single cell, shorting it out. They don't know what "something" is. All the stored chemical energy of the shorted cell runs thru the short and heats the cell up. The heat warms up the other cells and they fail too. The new batteries have a little more airspace inside them and more insulation around each cell. The idea is to prevent the chain reaction where all the cells melt down, and if it does, the stainless steel battery box will contain the fire and prevent it from setting the entire aircraft ablaze.
Let's hope it works.
No comments:
Post a Comment