"BRAKING DOWNHILL ON A FULL BATTERY WILL CAUSE BOARD SHUTDOWN since the regen will overcharge the battery. To prevent this from happening, the remote will warn you by beeping, and you’ll lose your braking power. Safely come to a stop before this happens, and ride on flats or uphill to drain the battery."
The other option is to divert braking energy to heat instead of recharging the battery. But on steep hills, braking energy can reach hundreds of watts, which would quickly overheat the electronics or motors without regen.
This is an issue that affects a very small subset of users, almost all of whom live at the top of a hill - definitely a unique corner case to design for. We tell them to discharge the battery by running it uphill or on flats briefly to discharge the battery enough to allow some regen headroom.
Assuming such parts exist, are they just cost prohibitive, or is there more to it?
(Thanks for taking questions!)
In general, if you're trying to evade (either with braking or acceleration), you have to know the state of your battery or else the car will not perform the way you think.
I don't know if all hybrid/electric cars are this way or if it's specific to my particular year of the HCH or what.
Nightmare situation for a SF resident who lives on top of one of the crazy steep hills, charges his board at night and is just about to head to work...
A supercapacitor is what should be the destination for the regenerated energy: it's empty by default; stable; could be discharged at high rate
Lithium-ion batteries are perfectly safe to regen. You need to monitor the cell and pack voltages and limit regen under certain conditions, but it's well understood how to do this.
Any electric vehicle with a lithium-ion battery (and there are millions of them, from skateboards and scooters to cars and trucks) does regen braking. Without regen, you lose one of the most compelling advantages of having an electric vehicle in the first place.
In general, supercapacitors do have much better power density than batteries, but much worse energy density, making them impractical for vehicles at this point in time. There's a reason the vast majority of electric vehicles today use lithium-ion batteries.
Disclaimer: I was formerly a controls and systems engineer for a hybrid-electric vehicle company.
https://www.youtube.com/watch?v=2QJVDGtzvEE
Not sure if this is feasible on this board, but you never know. If the wheels are soft enough, I think you could pull it off.
One of the most interesting things we've learned about recently is the temptation to cut corners using cheaper parts or processes or relaxed quality control procedures. It's easy to get quoted prices much lower than what we currently pay, but the long-term cost of choosing those parts (greater failure rates, manufacturing problems, and warranty costs, not to mention unhappy customers) is hard to quantify at decision time.
This is where experienced supply chain and hardware engineers are especially valuable. They understand the implications of these decisions and know the right way to account for them. For example, major manufacturers set aside "warranty accruals" as liabilities in their financials to cover the average future cost of servicing a unit that ships today.
I suspect this is a problem facing many hardware startups, Kickstarted or not. It feels non-intuitive to build hardware carefully and at such high initial costs, especially in the "move fast" culture of software development. And it's especially dangerous if a company goes "in the red" without realizing it by shipping many units that may fail or incur high warranty costs that exceed the margin on the product, but at a later date.
If you operate with a mindset of, "what you ship, you can't take back or modify," you're on the right track. It's in partial conflict with the software ideology of, "build an MVP and iterate fast." You can still do that, but the MVP can't suck.
Source: Shipped a pretty great product, still stay awake at night.
How does the board feels if you don't use the motor in case of empty battery. Are the motors braking per se or do they spin freely if no power is applied?
The motors spin freely when unpowered. It will skate like a normal board, but with a bit more drag.
I really want to love these types of transportation but I have a hard time seeing how they can scale without cities adopting to them. We already have enough trouble getting proper bicycling safety and then we introduce electric longboards on top of the existing skate/longboards and push scooters that already roll around on the streets and worse, sidewalks.
Maybe I am just biased because I dislike push scooters on sidewalks but then where is the push scooter legally able to go?
Even on the E-GO's (larger) 90mm wheels, 12 MPH is quite enough on a lot of the uneven pavement I encounter.
FWIW, the E-GO is a great deal for $700, and the range is considerably more. Maybe if I had to replace it I'd consider Boosted's product.
Seems more informative and less salesy-pitchey
http://evolveskateboardsusa.com/collections/carbon-series-el...
Boosted seems to be slightly cheaper, but Evolve boards have longer range and replaceable wheels for different terrains.
I think battery problems will be discussed more frequently as electric boards age. They make up a significant portion of the board cost and I hope suppliers have a good strategy to help customers when problems arise.
Boosted boards look awesome and I can't wait to try one someday. I only ride for fun and its typically 45-60 minutes at an average speed around 14-16mph, so a boosted board falls a little short in their range. I was wondering if Boosted had considered having an 'eco' mode that only runs one of the motors enabling extended range?
