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Page last updated: 5/17/2021

Commentary by S.D. Kaehler

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6/7/21: This month's online meeting had a turnout of 15 people. The meeting was facilitated by Steve Kaehler.

This meeting was recorded and is available on YouTube.

Club Business

  • The slides presented are provided here.
  • Shared links, notes, and comments are available here.
  • Note especially the upcoming Virtual Robothon Exhibition Event on July 10th starting at noon.
  • If you have ideas, comments, or presenter contact info, please email me at SeattleRoboticsSociety(at)Gmail.com.

Round-the-Room/Web

The following people shared information/projects.

Feature Presentation

    Our presentation was a facilitated discussion about electric vehicles led by Steve K. Here are the presentation slides: first half and second half and here are links to all the vehicles shown and lots of links to other things mentioned during the presentation. This discussion lasted nearly 90 minutes and only scratched the surface of this topic. There are many new vehicles coming out in the next several years so the landscape for EVs is rapidly changing.

    If there's sufficient interest in this topic, we could do another discussion, perhaps in-person so that folks can ride in different EVs to see what they're actually like. If you are interested, send a note to SeattleRoboticsSociety(at)gmail.com.

    A year ago I purchased my first EV, a 2019 Nissan LEAF. I have wanted an electric car since I was a teenager and considered (though not seriously) conversion of an Internal Combustion Engine Vehicle (ICEV), but at that time, conversions were very DYI since complete kits did not yet exist. I have always found EVs interesting and have followed the evolution of them over the years. When Tesla and Nissan finally started selling them, I thought this dream might be coming closer to reality. Riding in an EV is an interesting experience, but driving one really gives you an appreciation for how different they are from ICEVs. When I first test drove the LEAF, I was amazed at how smooth and immediate the power was. There's no vibration or hesitation at any speed. The quick acceleration was fun but more of a novelty most of the time. If you're in a situation where you need the car to move NOW, hands down, EVs will do this way better than ICEVs since there's no transmission down-shifting to wait on. I enjoy driving my LEAF so much that I prefer it over my other two ICEVs but have to give then a drive now and then to keep their batteries from going flat. If you haven't driven an EV, do try one out. I think you'll find the ride experience enjoyable and even addictive.

    What about converting ICEVs to electric power now? One interesting option is offered by Zero Labs Automotive where they replace the ICEV's chassis with a modern electric drive system. This sound intriguing but is kind of expensive unless you are really attached. DYI conversion kits are available for various cars but are geared towards folks who are comfortable rebuilding cars. Consider too that rolling and wind resistance significantly affect range. If you're interested in this option, I suggest watching a few videos before diving in. The economics of doing this depends on how attached you are to the vehicle you want to convert. Used EVs are quite available now and often reasonably priced perhaps making this a more viable option.

    12V Lead Acid Battery Issues: James May of Top Gear fame, owns a Tesla Model S that has an annoying deficiency. In this video, he describes how he recently he left his car parked and plugged in to a charger while on a trip of some duration. When he returned, the car wouldn't start. In fact, he couldn't even get into it since everything on Teslas seems to be electric. The 12V lead-acid battery had "gone flat" as he put it, rendering the car a giant, very expensive "brick". He describes the process involved in getting to this battery just to put a charger on it in a most entertaining way. Accessing the 12V battery isn't a problem with my Nissan LEAF because it is located in an easily accessible place under a mechanically releasable hood, however, on LEAFs, it isn't charged unless the car is turned on. Since I'm retired, I don't drive it every day, so I trickle charge it through a cable with an SAE plug on the end. Regular, periodic driving will keep the battery charged, but if the car sits for a while, a trickle charger can help keep it healthy. I can monitor the battery remotely via BT with this thing and a companion Android or Apple app. Another option is to automatically engage the climate control system daily for ten minutes or so, warming or cooling the car while it's plugged into power. This turns the car on, engaging the DC-DC converter that charges the 12V battery.

    Can an electric vehicle operate only on regenerative power? Under the right circumstances, yes. This article discusses how a Swiss rock quarry uses an electric truck that powers itself up a mountain using its 600KW battery pack, is loaded with many tons of rock at the top, then coasts back down recharging the battery regeneratively and actually generating more power than it uses resulting in a fully charged battery by the time it gets to the bottom. Of course the pack must have been charged from utility mains to begin the operation but once done, the truck now operates independently of utility power. The company operating this truck believe it is very cost-effective and much more efficient than their diesel trucks.

    Some Useful References:

  • Choose EV Facts
  • Department of Energy EV Info
  • Consumer Reports: Electric Cars 101
  • Inside EVs
  • Paramount Motors NW (Sodo District in Seattle)
  • PSE EV Incentives

The Workshop

    No afternoon workshop this month due to a beautiful sunny Saturday afternoon. We'll try to do something next month.

If you have comments or opinions on this writing, please email me at SeattleRoboticsSociety(at)Gmail.com.

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