Don’t really have a clue about e-bikes. But looking through some e-bike chargers on Amazon, they have maybe 100 W to 200 W.
USB-PD (EPR) apparently supports up to 240 W. Do note that the e-bike chargers are rated at 54.6 V, though, while PD only supports up to 48 V, and I guess the higher voltage might be required for the cell chemistry. So idk if it would be possible to design your batteries around the USB spec. In any case, you would need a separate charger and special cable to support 5 A over USB anyways.
It would be possible to put in a voltage converter that would boost the 20 volts that’s relatively common for USB-C/PD devices to whatever voltage the battery pack needs to charge while increasing the losses on the charge.
A 200 watt charger for a 48 volt 20 amp battery would be okay, but it would take like five to eight hours to charge depending on what kind of losses are involved.
It’s pretty rare to see USB-C charger that can handle 200 watts on a single port. More common is like 120, so it would take closer to 10-12 hours to charge that battery with USB-C versus a barrel plug.
And even if the cable is able to handle the 200 watts or more, it would be on the user to remember that they can’t plug in their 15 watt charger and actually charge their ebike battery.
So once you take all of that into consideration, given that you’re going to need a separate charger specifically for your e-bike battery, then why would it even matter that it’s USB-C?
yup, my thoughts exactly, don’t really see a any benefit for using USB-C here. What would be good of course is to have any standard at all for these connectors.
I’m not aware of any cell type with more than a few volts of potential. If we’re designing from scratch you just put fewer of them in series in each pack. There might be problems getting other components conductive enough to facilitate the needed power transfer at a much lower voltage, although now we’re outside of what I really know. If it’s 40V it shouldn’t be a problem.
While you’re at it standards for higher power DC would also be good. IIRC there’s a few in competition for EVs right now.
Good point. It’s probably an integer multiple of the (nominal? State of charge comes into it too) cell potential. Which is fine, as long as there’s another one that’s reasonably high but below the USB-PD maximum.
Don’t really have a clue about e-bikes. But looking through some e-bike chargers on Amazon, they have maybe 100 W to 200 W. USB-PD (EPR) apparently supports up to 240 W. Do note that the e-bike chargers are rated at 54.6 V, though, while PD only supports up to 48 V, and I guess the higher voltage might be required for the cell chemistry. So idk if it would be possible to design your batteries around the USB spec. In any case, you would need a separate charger and special cable to support 5 A over USB anyways.
It would be possible to put in a voltage converter that would boost the 20 volts that’s relatively common for USB-C/PD devices to whatever voltage the battery pack needs to charge while increasing the losses on the charge.
A 200 watt charger for a 48 volt 20 amp battery would be okay, but it would take like five to eight hours to charge depending on what kind of losses are involved.
It’s pretty rare to see USB-C charger that can handle 200 watts on a single port. More common is like 120, so it would take closer to 10-12 hours to charge that battery with USB-C versus a barrel plug.
And even if the cable is able to handle the 200 watts or more, it would be on the user to remember that they can’t plug in their 15 watt charger and actually charge their ebike battery.
So once you take all of that into consideration, given that you’re going to need a separate charger specifically for your e-bike battery, then why would it even matter that it’s USB-C?
yup, my thoughts exactly, don’t really see a any benefit for using USB-C here. What would be good of course is to have any standard at all for these connectors.
My laptop takes 300 watts from a proprietary charger and will only charge via USB-C when off. I don’t think it’s enough power for a bike.
I wouldn’t buy that laptop if I knew ahead of time.
There is no option for 300 W over USB-C, that’s beyond the USB-PD specification.
I’m not aware of any cell type with more than a few volts of potential. If we’re designing from scratch you just put fewer of them in series in each pack. There might be problems getting other components conductive enough to facilitate the needed power transfer at a much lower voltage, although now we’re outside of what I really know. If it’s 40V it shouldn’t be a problem.
While you’re at it standards for higher power DC would also be good. IIRC there’s a few in competition for EVs right now.
That’s what I thought too, initially. But then I thought that maybe there is a good reason for the specific 54.6V figure. But I didn’t dig deeper
Good point. It’s probably an integer multiple of the (nominal? State of charge comes into it too) cell potential. Which is fine, as long as there’s another one that’s reasonably high but below the USB-PD maximum.