• 6 Posts
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Joined 1 year ago
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Cake day: June 21st, 2023

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  • I imagine then that for an equivalent battery our sodium battery would weight 3 times as much and take up twice as much space as a lithium battery (plus any extra weight a larger housing or heavier mounting brackets add). Most of the ebikes I’ve ridden have batteries approximately the size of a 2L of cola.

    My battery would no longer fit fully in the downtube, or would have to be paired with a second battery. Perhaps putting it in the frame triangle would work. For larger bikes, like cargo bikes, I could see a large flat battery being put in the bottom of the wheelbarrow part without really being that noticeable. Even if only half of bikes changed over, it would still be a win.

    I’ve also visited a lithium mining area in the salt flats and what we’ve done to the indigenous folks’ land, communities, and to the people themselves is abhorrent. We can do better. Let’s hope these sodium batteries become available sooner rather than later, especially for circumstances where the weight/size are less of an issue.




  • I spent around $3750 for my ebike. As an example of what that gets you, I tested a lot of bikes, cheap and expensive and here’s what stood out to me:

    • Torque sensing rather than cadence sensing for pedal activation means my bikes torque scales with my own. A cheap bike just goes “oh, the pedals moved a half rotation, engage electric motorcycle mode”. This makes my bike feel more connected, it’s the difference between putting on an exoskeleton versus driving a walking robot from a cockpit.
    • Torque specs and maintenance info clearly listed, bike shop can get spare parts. While I’d like to see parts availability commitments become more common, right now the best you can do is go with a well known brand.
    • Frame geometry is often better on bikes from bike brands making bikes with tech than tech startups making bikes. This relates directly to on-bike comfort
    • As we’re all discussing here, battery quality can make a difference in safety and functionality.

    I hope this helps. I still think you can get a reputable bike at a good price, but I would generally skip the Temu, Amazon, no name rebrand ebikes out of concern for their quality.


  • I’m seeing that sodium ion batteries have lower energy density than lithium ion batteries. I’m not a chemist. So I had to do some searches and it appears this is measured by weight, not volume.

    Using hypothetical numbers to explain my question imagine that…

    • lithium battery weighs 1kg and has 5 stored energy units
    • sodium battery weighs 3kg and has 5 stored energy units

    How does this effect the space needed for the battery? If the physical density (not energy density) of sodium was 10 higher, maybe the battery weighs 3 times as much but because it is dense, that weight fits in a smaller (say 100 cubic units), heavier package. Conversely, if the physical density was 10 times lower the battery would be 3 times heavier but be 1000 cubic units.

    My question is basically what is the difference in physical density of the materials (kg per cm^2)?

    Unfortunately, ddg and google keep assuming I want to know about energy density.



  • Your point about the small companies is valid, and it used to be better. When Glassdoor was at its peak, you could find smaller companies more frequently and I would read up on the companies I did business with to get an employee’s perspective on whether they were functioning effectively. If your employees hate your guts or think their job is pointless, that’s also a bit of a red flag for me as a consumer. This Glassdoor research worked well for renovation contractors, larger service providers like electrical or plumbing, commercial real estate management companies. Sometime you could also find info that made it easier to navigate call centers designed to frustrate you into giving up. It looks like someone posted a few alternatives and glass door stopped being useful for company research almost as dramatically as google became ineffective for other research. Someday soon, all we’ll have is the company’s marketing slop and any honest opinion will be buried and hidden into non-existance.

    With regard to review manipulation, I knew a company with an abysmal rating, a real w2 farm. The people I knew spanned entry level to the c-suite. Said company would have bootlickers in HR and elsewhere post 5 star reviews to try to move the needle. They also asked people to rate them well after training had completed and everyone still had “new-job glasses” on. Despite their efforts, I think they were still sitting at a measly 2.7 stars, which is still way higher than the 1.5 they deserved. The 0.5 is mostly based on the bottomless supply of decent coffee in the break room :D

    I don’t have interactions with many people from this company anymore, but what I have heard is basically “different people; same shit”.










  • In my area, bikes are allowed on all sidewalks except for a street-bounded square around the downtown core where we must ride in the street. When on the sidewalk, we are expected to yield to pedestrians. This works in practice, mostly due to low volume of bikes and pedestrians, and in some places 12 food wide sidewalks specifically designated as class 1 urban trails that even allow some ebikes. In practice, this works okay but you are definitely forced to have little micro interactions with people to negotiate sidewalk space or signal your intentions. Cyclists go to the sidewalk as a last resort because it’s often not a comfortable place for us to ride, just less likely to get us killed. I will never understand cyclists who don’t ring. It’s a bad look for our ability to share space. Unlike cars, bicycles and pedestrians are close enough in speed to occasionally mix.

    I do agree that in city centers and high traffic areas, riders should dismount.


  • I also thought it was a bit of a wild request for bikes to only cross where bike infra exists. If we can’t make progress in driver behavior, we should build more mode separation to contain the thousand pound death machines in their own physically isolated section of the street. At no point should we be compromising bicycle or pedestrian mobility. We have a right to the street also, and it’s the cars who have trouble co-existing with the other modes of transportation without murdering a bunch of people.