How do you think solid state batteries will change how we use hardware?

ebike4healthandfitness said:
The Lyft BikeShare bike is just a little 500 watt ebike. It would not be able to take two passengers up a hill at a decent speed. To do that you would need much more than a 500 watt hub motor.
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It would not be able to take two passengers at all. It's not a two passenger bike.

I've ridden them down here. They are decent bikes. Lower performing than any of my ebikes, but for widespread adoption and use as a bikeshare you don't need to hit 35mph (or carry two passengers.)
 
markz said:
The Lyft BikeShare bike is just a little 500 watt ebike. It would not be able to take two passengers up a hill at a decent speed.To do that you would need much more than a 500 watt hub motor.
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I have no clue what those rental ebikes are, best guess is 36V 15-18A and 10Ah maybe 15Ah.
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36v with 15 to 18 amps sounds about right.

With the average american weighing 181 pounds https://news.gallup.com/poll/328241/americans-average-weight-holds-steady-2020.aspx , their clothes about 2 pounds and their shoes about 2.5 lbs https://whatthingsweigh.com/how-much-do-shoes-weigh/ the total weight of two average american riders without cargo is 371 lbs. Adding in the weight of a 84 lb Lyft BikeShare ebike (with seat room for only one person) https://www.fastcompany.com/90642114/new-lyft-e-bike brings total weight to 455 lbs.

As you can see below even with a 20 amp controller (rather than one that is 15 amps to 18 amps) a 12T MAC motor is very poor on hills when carrying two average americans (without cargo):

Up a 7 percent grade it only gets .4 mph (and overheats in 7 minutes):

https://ebikes.ca/tools/simulator.html?motor=MMAC12T&mass=206&hp=0&wheel=28i&grade=7&axis=mph

Up a 6 percent grade it only gets 7.1 mph (and overheats in 7.7 minutes):

https://ebikes.ca/tools/simulator.html?motor=MMAC12T&mass=206&hp=0&wheel=28i&grade=6&axis=mph

Up a 5 percent grade it only gets 9.1 mph (and overheats in 11 minutes):

https://ebikes.ca/tools/simulator.html?motor=MMAC12T&mass=206&hp=0&wheel=28i&grade=5&axis=mph

Up a 4 percent grade it only gets 11.4 mph (and overheats in 16 minutes):

https://ebikes.ca/tools/simulator.html?motor=MMAC12T&mass=206&hp=0&wheel=28i&grade=4&axis=mph

(Remember passengers having cargo, increasing weight of ebike so it can actually carry two passengers (rather than one) and reducing controller from 20 amps to 15-18 amps is going to lower the above figures)

P.S. I consider a decent speed for a rental moped up a hill to be 15 mph for a 15 percent grade (minimum), but it really should be 20 to 25 mph. (Remember that mopeds are in different class of electrical vehicle than an ebike and thus have higher power than the under 750 watts limit of Class 1,2 and 3 ebikes)
 
ZeroEm said:
15 degree min. You live in the Alps don't you.
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It must be someplace steeper! L'Alpe d'Huez is probably the most famous climb in the Tour de France, and it tops out at 14% grade, or 8 degrees.

The steepest parking ramp permitted by the International Building Code is 6.67%, or a bit less than 4 degrees.

15 degrees is 27% grade-- slightly steeper than any paved city block in Seattle, which is a famously steep city.

I think our friend would benefit from direct observation and hard data gathering on this topic and on many other things as well.
 
ZeroEm said:
15 degree min. You live in the Alps don't you.
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I mislabeled percent grade as "degree slope" throughout my post above yours.

Now it is fixed.

For example where it originally said "Up a 7 degree slope it only gets .4 mph" now reads "Up a 7 percent grade it only gets .4 mph".

So yeah, just awful performance as I predicted.
 
When a hub is used as a middrive theres 2 freewheels on 1 chain and the lightest to operate wins but if the rear is locked up the hub can use the rear deralier in a sequential mode fireshifting through gears as the wheel turns and give crazy high efficiencys but theres no peddle ability then the hubs in the way

Stubborn people look for solution's and there looks to be a way of using a fatbike 150mm front fork 15mm through axle with a 150mm rear hub same axle diameter then make a deralier hanger mount and fit a small hub on the fork in the chain line so it turns with the wheel and can manipulate a full cassete worth of gears with the same freewheel setup as above all the gears will have full sequential aslong as the bike is moving and by keeping the janky bit to the front the rear is kept to delivering the might of the human leg the bars will be cluttered mind lots going on while driving it but it could sip juice like no other with a set of biscuit tyres.
 
ebike4healthandfitness said:
For example where it originally said "Up a 7 degree slope it only gets .4 mph" now reads "Up a 7 percent grade it only gets .4 mph".

So yeah, just awful performance as I predicted.
Click to expand...

I don't know or care what settings you used, but I think if you actually tried it IRL, that wouldn't be the result you got.
 
Chalo said:
... 15 degrees is 27% grade-- slightly steeper than any paved city block in Seattle, which is a famously steep city. ...
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I am certain that your information is correct but in my misspent youth there was a hill on 5th Street NE in Centerpoint, Alabama that I always had to push my bicycle up. The other reason I remember that hill is because when learning to drive, I hated it. Going over the top I could not see the road ahead because the downslope was hidden by the hood of the car and I was by no means a short driver. One could not see if there was an oncoming vehicle or some kid standing in the middle of the street. It seems to me it had a somewhat steeper angle ... but hey I am getting senile.
 
Planning my first build come about from a short hill needed to climb up from greenway trail 2 miles from my house. First time up it, could not down shift fast enough to keep moving. Had to walk the bike up from half way. This hill is not very long 0.2 mile and don't know the grade +7%. Its one of them you do not see the road close to the top. This hill was the base's of how the my eTrike ended up.
Started with a AWD bike and ended up with my leafmotor trike, which does it with out a second thought. I understand when one has no experience and the design thoughts run wild in the mind of what is needed. Once you do some riding and have realistic goals then it is not hard.

Have some experience with heavy vehicles on grades. Going up is one thing but going down is another animal all together. The grade itself does not mean much with out how far or long. It's all about heat going up and down.

This is the grade I think about most: Did some custom cutting one summer from Texas to Montana. Driving a dump truck pulling a combine.

Traveling US 160 Wolf Creek Pass: BEWARE THE WOLF

East side of the pass the grade is not to bad but last for seemed like 20 miles. The West side is much shorter 7% with sharp turns, gets the adrenaline flowing.

When people throw out numbers sometimes they seem wild and expect to much. It's not all about power it's about heat.

My little hill I can top it above 20 mph with just the motor (2500w-3000w) but most of the time just put my power switch in low about 8-900w hold the throttle open and peddle to maintain 10-15 mph. Motor runs much cooler. Going down this hill, engage regen at the top going slow and still hit over 20 mph. Make more heat going down.
 
LewTwo said:
Chalo said:
... 15 degrees is 27% grade-- slightly steeper than any paved city block in Seattle, which is a famously steep city. ...
Click to expand...

I am certain that your information is correct but in my misspent youth there was a hill on 5th Street NE in Centerpoint, Alabama that I always had to push my bicycle up. [...] It seems to me it had a somewhat steeper angle ...
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There are isolated short slopes all over the place that might exceed what we're talking about, but start and finish in a very short distance. Poorly planned driveways, for instance.

For visual reference, here's a Google Maps link to the steepest city block I ever found in Seattle, which is 25%. Click the "Street View" window and have a look around. Some of my friends pedaled up it for sport, but I never wanted it that much. Either of the e-bikes I rode when I lived in Seattle would have stalled out on this slope.

And here's one of the steepest arterial streets in Seattle, a section of Queen Anne Avenue called "The Counterbalance" after a counterweighted cable car that used to run on that section of street. Its maximum grade is 20%.
 
Chalo said:
ebike4healthandfitness said:
For example where it originally said "Up a 7 degree slope it only gets .4 mph" now reads "Up a 7 percent grade it only gets .4 mph".

So yeah, just awful performance as I predicted.
Click to expand...

I don't know or care what settings you used, but I think if you actually tried it IRL, that wouldn't be the result you got.
Click to expand...

Chalo,

I think you might be the only person in this forum that believes in this preposterous idea of an OEM built 500 watt hub motored ebike that could take two adult passengers up a hill at decent speed.
 
Here we have a few short sections of streets that are 20+%. The worst are those that have a stop sign mid climb, for they can kill many ebike motors and gassers clutches, even some cars had sled backward down the hills. All of them are dangerous because we have snow and ice in the winter. I have seen parked cars suddenly sliding down the slope on days of heavy rain.

Climbing steep is much more dangerous, and harder on motors on the streets than off road. Off road you can speed enough to attack a steep section with momentum, or lay down your bike on the side of the trail if you loose traction.
 
I cant even tell the grade of a slope when I am riding.
I checked twice with an Android App, one was a long hill with a steep section 24% that was very short 10'. Another hill was very steep 27% for 150'
both pathways.
 
ebike4healthandfitness said:
Chalo said:
ebike4healthandfitness said:
For example where it originally said "Up a 7 degree slope it only gets .4 mph" now reads "Up a 7 percent grade it only gets .4 mph".

So yeah, just awful performance as I predicted.
Click to expand...

I don't know or care what settings you used, but I think if you actually tried it IRL, that wouldn't be the result you got.
Click to expand...

Chalo,

I think you might be the only person in this forum that believes in this preposterous idea of an OEM built 500 watt hub motored ebike that could take two adult passengers up a hill at decent speed.
Click to expand...

1) None of us can say, without measurement or a specification, how much actual power or torque a "500W" bike produces.

2) What speed qualifies as "decent" is a matter of taste or lack thereof.

3) I didn't claim the bike would go fast or at all, only that it wouldn't conform to your prediction.

4) You have already shown us that your real world experience with any of this stuff is negligible to nonexistent.

How many nominally 500W bikes have you built? How many have you ridden? As for me, I recently threw away 22 security axle nuts that had built up from fitting 250/350W (nominal) hub motors with 500W (nominal) controllers. So that's eleven of them in the last while, with fourteen left to go if I don't order any more.

None of these bikes so far have been tandems or passenger carriers. But if I were called upon to make one, I could make one that works. I could even furnish details about how I'd approach it, but that information would be wasted on someone who doesn't have relevant experience.
 
ebike4healthandfitness said:
[I think you might be the only person in this forum that believes in this preposterous idea of an OEM built 500 watt hub motored ebike that could take two adult passengers up a hill at decent speed.
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Would or could?

A lot depends on what is the definition of "two adult passengers". There is a world of difference between a pair of 120 feather weights or two rather more robust individuals that toss around small refrigerators for a hobby. We are talking about electrically assisted bicycles here. Most common bicycles frames are rated for total loads of 300 pounds or less. Leave us not forget any cargo they might be carrying (back when I was in school that might be 20 or more pounds of books each ... do students even use books anymore). You will also find that number or one close to it used for E-bikes as well.

Speaking of being built for "adults" ... a more irritating problem for me is that the vast majority of those frames are sized for short people (those folks that need a boost to see over a five foot fence). Back in the day many OEM's built frames in various sizes (not wheel sizes but actual FRAME sizes). Now most OEMs (both bicycle and E-bikes) depend on sticking the seat up somewhere around control tower height for anyone near 6 feet tall or better.

My point being that OEMs are going to build what they think they can sale to 80% of the market (appropriate or not) and screw the rest. Nothing else matters.
 
Chalo said:
ebike4healthandfitness said:
Chalo said:
ebike4healthandfitness said:
For example where it originally said "Up a 7 degree slope it only gets .4 mph" now reads "Up a 7 percent grade it only gets .4 mph".

So yeah, just awful performance as I predicted.
Click to expand...

I don't know or care what settings you used, but I think if you actually tried it IRL, that wouldn't be the result you got.
Click to expand...

Chalo,

I think you might be the only person in this forum that believes in this preposterous idea of an OEM built 500 watt hub motored ebike that could take two adult passengers up a hill at decent speed.
Click to expand...

1) None of us can say, without measurement or a specification, how much actual power or torque a "500W" bike produces.
Click to expand...

A 500w bike from a reputable OEM is going to make around 500w peak (Markz prediction of 36v 15-18 amp controller I believe is spot-on for a reputable OEM 500w bike). This to serve Canada (which has a law stating a max of 500w peak) and to allow product segmentation with higher powered "under 750w (peak power)" OEM bikes in the United States.
 
Actually I think its 750W in Canada
But maybe the scooters are different. I would guess that the rental scooters want to be well below the 750W limit for liability reasons. City halls are to stupid, insurance companies are not.
 
markz said:
Actually I think its 750W in Canada
But maybe the scooters are different. I would guess that the rental scooters want to be well below the 750W limit for liability reasons. City halls are to stupid, insurance companies are not.
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Every link I read says ebikes in Canada must be 500w or less whether it is peak or continuous power.

Not sure what all the laws in Canada are for Mopeds (which is a topic of this thread for two passengers). I know in British Columbia an electric moped can have 1500 watts.
 
BalorNG said:
It is much better to battle those losses with very thin laminations, too. 0.2mm and even 0.15mm are common on RC motors now and they do not cost a fortune!
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I found a very interesting thread talking about MAC using .27mm laminations for the stator beginning end of 2016.

https://endless-sphere.com/forums/viewtopic.php?t=83943

Previously MAC was using .35mm and before that .5mm laminations.

I wonder how soon we see .2mm laminations.....and what other changes will accompany that for the MAC hub motors? Maybe a greater reduction via two stage planetary gear reduction?
 
ebike4healthandfitness said:
Maybe a greater reduction via two stage planetary gear reduction?
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No. That would entail both greater cost and greater efficiency losses, so it would only appeal to fetishists and not to the engineers who could make it happen.
 
There are already two stage reduction hubs, but with light weight, not high power in mind.
Nothing prevents one from upscaling it from 250w to ~1000w.

But frankly, I still think that key to perky accelerations and good climbing ability AND high cruising efficiency AND regenerative braking is simply using two motors, one direct drive (or fixed gear middrive), one geared (preferably dual reduction geared) hub motor with an overrunning clutch. You can have it light, efficient and output lots of torque.
 
Then we are back to the topic of energy density, which is the solution that will make obsolete such redundancy, complicated design with 25 times the moving parts for the purpose of saving power usage.
 
Some reason unknown to me. Have been focused on a two speed. So have been thinking about dual voltage system (sounds craze to me too.). Currently ride greenways and with regular bikers at 15 mph. Then less often ride the roads outside of town and with roadie bikes which is faster 20 -28 mph.

Have been thinking about having the option of switching from 36v to 72v. This would keep me in the best range for each task. My current controller can't do 36v, the Phaserunner can. My current batteries drops (splits) from 72v to 36v currently with a flip of a switch. (use this only when connecting the battery currently)

Then there is the settings not matching the battery voltage. And would worry about staying in balance. Would not want to switch back and forth during a ride. The only reason for me to think of such is that the greenway riding will get better w/km and keep my motor from running the 35-50% range. At 36v would be max out at 17 mph and 72v would be 33 mph. Don't think I will do this, just need two different bikes. But there it is, comments?

by MadRhino » Oct 10 2021 10:05am

Then we are back to the topic of energy density, which is the solution that will make obsolete such redundancy, complicated design with 25 times the moving parts for the purpose of saving power usage.
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I have a 36V 35A generic controller and two batteries, one 52V 14.5Ah and one 36V ~20Ah
I leave one unplugged and have the other plugged in.
When I run out of battery juice :lowbatt: I stop and unplug the battery and plug other one in.

I test rode yesterday going real slow and doing lots of pedaling. I wanted to check out the 150yr old tree the Calgary Flames will be cutting down to make way for the new stadium.
On the old used 36V battery charged to 40.40V total, I did 40km total distance, normal distance is 20-24km. I want to do another test run with the 36V battery charged to 41.50V.

Test run on the 1 year old Grintech battery when new, was about the same distance 22-25km normal riding, but I am guessing its about the same distance as its roughly the same Wh batteries.

I guess one could simply use a high current dc switch with diodes when you want to only use one controller. I would put multiple diodes inline for multiple safeguards (but not to many as it reduces voltages) to block back current from one battery to the other. That would be nice for me for the hills to just flick a switch, I wouldnt be doing no two controller setup, or two motor setup.

Doing some quick maths thats 18wh/km which I am used to getting 33wh/km.
I bet instead of cruise control and installing a cheap pedal assist forcing me to pedal all the time I could do better. As with just using cruise control, at times I will pedal along other times I just wont. I just like cruise control because I go a constant speed but its hard to engage on bumpy pathways, hold throttle steady for 10 seconds. Then other times cruise is engaged when you dont want it.

But I have recently learned some stuffs. Watching a few videos and reading a few ES posts. Justin said in the warehouse tour he used to snub his nose at pedal assist, now he loves it so I might give it a go.
Lots of ES posts are similar.
 
BalorNG said:
There are already two stage reduction hubs, but with light weight, not high power in mind.
Nothing prevents one from upscaling it from 250w to ~1000w.

But frankly, I still think that key to perky accelerations and good climbing ability AND high cruising efficiency AND regenerative braking is simply using two motors, one direct drive (or fixed gear middrive), one geared (preferably dual reduction geared) hub motor with an overrunning clutch.You can have it light, efficient and output lots of torque.
Click to expand...

How about this one?

https://electrek.co/2021/09/07/bafang-unveils-electric-bike-motor-with-2-speed-automatic-shifting-and-torque-sensor/

Is it too weak to help despite its ability to switch gear ratios? I'm thinking it might be unless it uses thin enough laminations thus allowing a deep enough first gear.
 
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