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  1. Kiwi_ME

    Interesting electrification analysis article

    Thankfully that doesn't matter, the effect is the same. The comments under that Levin article are just hilarious! Just what I needed for a Friday laugh.
  2. Kiwi_ME

    Warm an EV before driving off?

    "Always be charging" or ABB in EV parlance simply means don't pass up a charging opportunity if it presents itself. More applicable to the early days of the Leaf than now.
  3. Kiwi_ME

    Warm an EV before driving off?

    I've measured my Kona's average battery cycle efficiency and it's 98%. So, while driving at highway speed with the motor drawing an average of 15 kW, the battery loss means 1% of that is lost as heat, 150 watts. Heat losses from the inverter are also available and that could add three times what...
  4. Kiwi_ME

    Warm an EV before driving off?

    Right, sometimes I forget that you have winter over there. I'm not sure if the Kona can do the battery in the preconditioning phase.
  5. Kiwi_ME

    Warm an EV before driving off?

    Good questions. The battery management system knows what the battery power limits are and those numbers can be read over OBD on H/Kia EVs. Generally every EV will have a means to heat the battery, usually a resistance heater of some description in the coolant loop and using that of course is...
  6. Kiwi_ME

    Warm an EV before driving off?

    Your's uses a full-synthetic ATF and mine a 70W GL-4 gear oil, which is much the same as far as gears and bearings are concerned. Unless you're hearing a gear whine when starting off there's really nothing to worry about. In the 5 years I've been following H/Kia forums no one has ever reported a...
  7. Kiwi_ME

    Warm an EV before driving off?

    Nothing at all. You can beat on it the moment you drive off. In below freezing temps power may be limited until the battery warms up and many EVs have means to warm the battery pack coolant.
  8. Kiwi_ME

    An EV I would buy

    A 2-seater is a bit unlikely because hardly anyone else wants that in a cheap car. The Fiat 500e is close with 200 miles of range and a back seat you wouldn't want to sit in. I've heard Bolt seats are pretty awful and it will have close to the range you want but not in winter. Not sure why you...
  9. Kiwi_ME

    Optimal EV Charging

    I'll wait until I get down to around 45% percent then add 20% overnight using the portable 1.7kW charger to bring it up to 65%. At least for this NMC cell chemistry the effect of sitting at some charge level on degradation is like a bathtub shape around ~50%. If I needed more than 20% daily I...
  10. Kiwi_ME

    BMW EV's - Battery modules replaced individually

    There are battery pack teardown videos on YouTube for all sorts of EVs. Tesla's in-house round-cell designs are potted after the cover is attached to ensure they don't move - making them exceptionally difficult to repair. By saving costs up front using a round cell, they simply moved the design...
  11. Kiwi_ME

    Hyundai price gouging new EV battery, or so it seems??

    Keep rocking that 1-star safety rating!
  12. Kiwi_ME

    Hyundai price gouging new EV battery, or so it seems??

    Since the subject came up and I've not looked at these before, I thought I would check out one of these allegedly "low quality products" at the dealer in the next town. I'll note that Chinese-designed and built models are flying off the shelves here in NZ at 3/4 the price of base-spec mainstream...
  13. Kiwi_ME

    Something that is lacking with EV discussions.

    The start motor example with a fixed commutation angle is simply not comparable to the sophistication found in 3-phase motors (with either PM or electrically-excited rotors) with high-frequency inverter drives that have been used widely in industry for 2-3 decades and now EVs. Every factory...
  14. Kiwi_ME

    Hyundai price gouging new EV battery, or so it seems??

    It's an overreaction from the dealer likely because Hyundai did not document service limits for damage.. There's a protective fibre-type sheet, then an aluminum cooling panel stamped to form channels, then the pack underside itself. The cells are installed in further aluminium housings to form...
  15. Kiwi_ME

    Musk Says Tesla ‘Dug Our Own Grave’ With The Cybertruck

    Unless I've missed something the few innovations are: 1. Steer by wire. At both ends. 2. 48V auxiliary power to an unspecified percentage of the car. Clearly it's highly desirable for the electric power steering but what about all the other peripherals like door window motors, computers...
  16. Kiwi_ME

    Visited Mercedes-Benz first ever North American charging hub.

    Don't the wheels fall off at 100%? :) I'd think the cost of real estate in that location would be the killer for ROI.
  17. Kiwi_ME

    Model 3 cabin air filter; horrible engineering

    The filter on my Kona EV, much maligned as being based on a non-EV-dedicated platform, can be changed in under 2 minutes. Munro Associates has a recent video covering the evolutionary differences between a couple of Tesla's cylindrical-cell type battery packs. These of course have serpentine...
  18. Kiwi_ME

    Gasoline price vs electricity price

    Lol, I'm a mechanical engineer and after a year of owning the Kona EV I bought a used manual-trans 4WD only because I missed doing normal car maintenance. I love the EV but driving the ICE is like the kid's cars you find in malls that you put a coin in. Yeah, they still have 'em here.
  19. Kiwi_ME

    Gasoline price vs electricity price

    My ratio is $3.055/l x 3.785g/l over $0.263 = 44, but more importantly my very small gasoline SUV costs 7 times more to fuel than the EV. That said, that savings could never cover the lost opportunity on the nz$40k added cost of purchasing the EV, without driving considerable miles/year. But...
  20. Kiwi_ME

    EVs with different types of heaters?

    The heat pump in my Kona EV draws around 0.6 to 0.8 kW in winter, about the same as the AC in summer, about 4% of the total draw from the battery when driving at highway speeds. When starting under 7°C the cabin resistance heater (commonly referred to as the PTC) kicks in first, drawing about...
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