> While working on our goal of making the power train last a million miles, we came up with the idea for an advanced smart fuse for the battery. Instead of a standard fuse that just melts past a certain amperage, which means you aren’t exactly sure when it will or won’t melt or if it will arc when it does, we developed a fuse with its own electronics and a tiny lithium-ion battery. It constantly monitors current at the millisecond level and is pyro-actuated to cut power with extreme precision and certainty.
That was combined with upgrading the main pack contractor to use inconel (a high temperature space-grade superalloy) instead of steel, so that it remains springy under the heat of heavy current.
The net result is that we can safely increase max amp throughout from 1300 to 1500 Amps. If you don’t know much about Amps, trust me this is a silly big number of Amps to be going through something the size of your little fingernail.
What this results in is a 10% improvement in the 0 to 60 mph time to 2.8 secs and a quarter mile time of 10.9 secs. Time to 155 mph is improved even more, resulting in a 20% reduction.
At high levels of current it takes pretty drastic measures to break the circuit. Even if the conductor melts away you can still have arcing, turning the air into plasma and a replacement conductor.
Kind of nuts that they had to account for that in a car.
Oh jeez. Never mind my sibling comment - this sucker seems hellaciously sophisticated, far more so than I was imagining. An active fuse that carries 1.5kA that's the size of a finger? I've seen fuses wider than my wrist blam for less.
Wow is that 1500A with DC current? Wouldn't there be a big magnetic field generated when so much power is pulled through the wires/bus bars from the battery? Would be kinda funny to do an insane mode launch and your pocket change flys out of your pocket and sticks to the floor.
Well, SpaceX uses inconel. They also must have a quite good understanding of pyrotechnics, as they need to use that in a lot of places, eg. stage separation.
So I'd say yes, at least on the tech transfer part.
I don't think so. At least, it hasn't been publicly reported as far as I know. So although I'm not saying it's impossible, I'd be very interested to know the source for your statement?
Without the performance characteristics for the fuse, I wouldn't imagine it would be cheap. Specialized electronic components are usually very expensive, especially if they're never mass produced and engineered to a specific task (component ICs for devices in space face the same issue). That engineering is pretty damn expensive, the tooling to make the small run of components is expensive, and quality control is expensive. Make a few hundred million and those costs vanish compared to the input materials, compared to a few thousand components where the overhead dominates.
Market segmentation. How do you get people to pay you another 10k? With a widget that is useless but has huge bragging value. People who don't care about 10k will spend it on this, and those who do care will have no different lives.
[1] http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3D...