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  1. liveforphysics

    PaulD's Experiments with Endothermic Potting Compounds

    Fantastic testing Paul! I've never tried washing soda, but it looks very promising from your data! How exciting!
  2. liveforphysics

    Thread for new battery breakthrough PR releases

    I think you mean Wh/kg not Wh/Liter, as many commercial cells are >700Wh/liter. With respect to Wh/kg though, lots of large scale production automotive pouch cells >300Wh/Liter today and amazing cycle life. Wh/kg is always nice, but seeing it with a low specific impedance is what most...
  3. liveforphysics

    Suzuki GSX-R e899 K2

    Glad that you're not injured my friend!! Sounds like the bike is going to rip super hard when you get a clean pass in!
  4. liveforphysics

    Thread for new battery breakthrough PR releases

    They made it clear that it didn't trigger TR from nail pen, as many other pouch cells will also achieve. This should not be confused with TR behavior being safe or unsafe, as no TR safety behavior was shown. That nail pen setup with the faceted nail tip which cuts like a broadhead is easier...
  5. liveforphysics

    Thread for new battery breakthrough PR releases

    If things got as drastic as being limited to 700hp, I would sit and wait for the heat pumps to pre-heat the cells before driving. ;)
  6. liveforphysics

    PaulD's Experiments with Endothermic Potting Compounds

    Love to see this work Paul! Thank you for sharing your tests. With the right endothermic fillers, you can pack feisty cells tightly together and still have 100% success in passing PPR (passive propagation resistance). If you have a Ramset nailer, throw a nail or two into cells in your test...
  7. liveforphysics

    Thread for new battery breakthrough PR releases

    Theres already public data with numbers better than 315Wh/kg. They didn't stop development at 327Wh/kg. They are in normal thickness pouches with beefy thick tabs and thick foils for high C-rates. https://www.greencarcongress.com/2022/04/20220413-zenlabs.html
  8. liveforphysics

    Thread for new battery breakthrough PR releases

    The cells are real. I was extremely surprised with the electrical performance.
  9. liveforphysics

    I tried to dismantle the most dangerous and hideous diy ebike battery ever made

    If you don't pot the battery, it's a disposable fire hazard when exposed to humidity and time. Potting doesn't impact cell venting, I have the pressure curve data for different cells CID and vents to open in potting or bare, it's within a percent of the same pressures. Potting in the right...
  10. liveforphysics

    Arctic Leopard dirt-bike, 72V

    I think a proper bike should throw your ass on the ground hard if you get in and whisky-throttle it. The bike and powertrain did exactly what I want a dirtbike to do, I was just too stupid of a rider to recognize I was on a proper bike at the time I went WOT.
  11. liveforphysics

    Arctic Leopard dirt-bike, 72V

    When I have a free few hours to spend, I will open it up and take a look and share pics and lam thickness.
  12. liveforphysics

    Arctic Leopard dirt-bike, 72V

    I have one of them, it's pretty amazing. I've only ridden it once because I wheelies over backwards so violently on my first part of my first ride that my leg hasn't recovered yet to have a second ride. Bad ass machine, suspension feels good, brakes feel soft, power and torque hit is serious and...
  13. liveforphysics

    Axiom: a 100kW+ motor controller

    Potting is #1 protection. A large enough bellows with molecular sieve packs is also a feasible option, but may require a maintenance interval to swap out the sieve pack for the humidity that migrates through polymer materials, like the bellows.
  14. liveforphysics

    Axiom: a 100kW+ motor controller

    Looks beautiful my friend. Make sure you put fresh humidity scavenger packs in just before sealing the lid. It's not uncommon for them to use up the first 70% of there sorbtive capacity in an hour or two of being inside a normal humidity room. I also have seen some of the silica gel style...
  15. liveforphysics

    A warning about KO controllers

    It's tough to say how thick those copper bars are. I'm hoping they are 3+mm thickness and say 10-12mm width (between each parallel pair). If it's ~33mm^2 will heat at 800amps from 50degC to 100degC in 14seconds assuming no cooling. In my experience with an 830Amp Sur Ron, it's very difficult...
  16. liveforphysics

    A warning about KO controllers

    The controller doesn't look too bad to me for an ebike controller. Less refined than an ASI, but above average design.
  17. liveforphysics

    Charge fast by paralleling with a full charge battery.

    Lots of small, cheap, and efficient DC-DC converters exist to accomplish the same goal, but safely and with constant current. Some of the small cheap DC-DC converters I dyno'd for efficiency exceeded 99%. This enables the whole system size and weight to be smaller as it doesn't need thermal...
  18. liveforphysics

    My QS205 runs circles around a QS273!

    If they pull that much difference in power at the same speeds, it's a significant difference in motor kV. Do you have a power supply and dmm to measure the phase resistance?
  19. liveforphysics

    are 18650 safe overchrged from 4,2V to 5,0V?

    Don't breathe it. Too many partially decomposed organics and F/HF ion radicals to scar your lungs. Manganese also is toxic, and lithium impacts your brain function in non-reversable ways.
  20. liveforphysics

    are 18650 safe overchrged from 4,2V to 5,0V?

    This is definitely not true in any aspects of it. In overcharge, the cell often goes from just a few degrees over ambient into plasma runaway. It also happens as a knife edge at the instant the overcharge over lithiation and voltage stress breakdown the SEI at its weakest location.
  21. liveforphysics

    Suzuki GSX-R e899 K2

    Stoked for your new packs making that bike go much faster!!
  22. liveforphysics

    Electrical Contacts: conduction improving agents

    Ive tested this type of connectors sealing. It only passes corrosive vapor testing when it's packed with dielectric grease inside the cavity. Gold plating only buys a few volts of electrolysis. Little round wire seals mating into square connector body ports has never passed a vapor sealing...
  23. liveforphysics

    Electrical Contacts: conduction improving agents

    With respect to precision, I test tiny connectors at 10Amps R measurement, medium connectors at 100Amp, and beefy connectors at 1,000-5,0000Amps. With the voltage drop across the joint instrumented with the Nanovolt meter, I'm able to see changes in resistance repeatably at 0.0001mOhm or...
  24. liveforphysics

    Electrical Contacts: conduction improving agents

    I do test joint performance in extreme conditions. High G force vibe, multi salt blend salt spray testing and temperature cycles from -140degC to +100degC. We also use much more extreme mixed corrosive acid vapor exposure tests, which tend to destroy all the metal parts that aren't covered...
  25. liveforphysics

    Electrical Contacts: conduction improving agents

    We have 5,600Amp CC-CV supplies and 7.5digit nano-volt meters at our lab I use to test. The most important function is to displace humidity and vapor from the clean contact surfaces. Many have corrosion inhibitors to further reduce rates of corrosion. All the filled greases I tried just had...
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