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Hacking the Nissan Leaf EV
An anonymous reader writes "The New York Times is running a story on people hacking the Nissan Leaf electric vehicle. 'Using Mr. Giddings’s home-brewed E.V. fuel-level display, Leaf drivers get the confidence to extend their driving range by 10 percent or more. His gauge, which displays the actual state of charge, reveals that the Leaf dashboard’s "zero bars" display comes on when the battery pack has several miles remaining.' Here's an interesting quote from one of the hackers, Phil Sadow, who was interviewed for the story: 'I don't like the term hacking because it's been portrayed by the media as something evil. To me, hacking is actually very American. Go out to the garage. Take it apart. Make it better.'"
It just shows how much of the last bar you still have. Once you go from one bar to zero, you essentially only know you have "less than one bar" left, but not how much. There is no change to how deep the batteries get discharged, you just know better what risk you are taking if you decide to drive on. The TFA also tells about the software "hack" to the 120V charge cable to make it work with 240V as well. That's not so special, considering the same cable is used with different software in Europe, where 240V is the standard. Also improving it to be better, but not different.
I was promised a flying car. Where is my flying car?
No, you shouldn't with any kind of modern battery.
Li-Ion doesn't like full discharges, and in fact the internal circuitry should make it impossible. Lead-acid will very quickly become unusable if left fully discharged. And for battery packs, full discharge risks cell reversal, which causes damage.
The only case where you should still do that is when there is some sort of internal statistics being kept of how long the battery is estimated to last, which is out of sync with the actual battery.
That's not for any sort of cleaning though. It's just for fixing incorrect estimations of remaining battery time, which causes devices to turn off too soon, or have them fail to shut down nicely before the battery runs out.
Gas powered cars still go many miles after the gas gauge hits empty. A fuel gauge reading empty is suppose to tell you "Fill up as soon as possible" not tell you need to get out and push.
Empty means buy a new fuel pump because the old one just sucked up all the water, rust, sand, whatever from the bottom of the tank. Also the in-tank pumps are notorious for overheating and burning out in air/vapor and only running cool when immersed in fuel, so even a perfectly clean tank can burn out the pump if the pump is in an empty tank. Maybe more so in summer than winter... Also if the pump fails after pumping rusty water for awhile rather than instantly, you'll probably end up replacing the fuel filter, maybe the injectors, who knows.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger