100+ Miles of Fun per Charge: 5.1kWh batt, 20kw capable

[Powervelocity.com]

Just completed a new build.
The initial goal was pretty simple: get the longest range out of the ample battery space allowed by the enduro frame and specifically 140mm width that made it possible to put two big bricks of 18650 cells alongside. Obviously, it came with some weight penalty (battery pack alone is around 50lbs) but at some point that was not a concern anymore. Initial tests and estimates show that the bike is capable to reach 100 miles of range per charge (yet to actually ride that distance) provided that consumption stays around 50-60Wh/mile (doable at speeds up to 35mph). But even at 40-50mph, the range should be respectable 70 miles.

Even though I was not after more performance to start with, the side effect of having a larger pack is that you instinctively want to use more kw when you know they are there plus the added weight required more kw to reach the same acceleration levels. So, I am now upgrading my MXUS with QS motor and, likely, will look for a controller capable to do at least 15kw.

Anyway, here are some quick specs:
- 24s20p pack Panasonic PFs 88v 58Ah nominal, 5.1kWh, 10kw output BMS limited, the pack is shaped to fit enduro frame but with some space carved out for the on-board charger.
- 100.8v 5A charger on board, and external charge port that's ready to take up to 27A (2700W) of fast charge
- MXUS 3T in 17'' MC rim with Shinko 3'', soon to be upgraded to QS 205 to re-mediate some overheating issues under continuous load
- 24Fet sinewave Chinese controller, works fine, but not programmable unfortunately, so it is to be replaced with something configurable and capable of 15kw (suggestions are welcomed)
- enduro frame, DNM fork and rear shock
- lighter 2'' moped wheel in the front - might be a bit too weak for this build, thinking about replacing with something wider and, likely, heavier

And below some pics.

Cell arrangement. Two of these bricks fit nicely into the frame. 5.1kwh with these cells. With 3.5Ah cells available now, the total energy capacity can be raised to 6-6.5kWh which can potentially bump up the range to 130 miles per charge



Some space left for the onboard charger with "exhaust" holes drilled under the seat for heat generated by the charger (cells of this chemistry and in this arrangement are pampered at 10kw staying cool)



Completed build but a few things to be upgraded for more power and reliability

View attachment 1

Test ride with fellow ebikers

 

[Chalo]

Yet you have pedals on it. Why?

Would you put cranks on the side of a diesel pickup truck and call it an e-bike?

 

[liveforphysics]

Yet you have pedals on it. Why?

Would you put cranks on the side of a diesel pickup truck and call it an e-bike?

I wouldn't mind having pedals on my modded 2015 SR, just because it's nice to get some exercise while riding. Many folks pay good money to go to a gym and sit on a machine that doesn't even move to pedal.

It's a nice bike with excellent car replacement functionality and I bet it's a hoot to ride.

 

[Chalo]

If it's for getting Sisyphus-style exercise-- sure, whatever. But most things like this are meant for abusing access and regulatory privileges extended to actual bicyclists, privileges that are both hard-won and constantly under attack.

It would be easier to welcome this kind of high power e-bike if it had a license plate and a valid registration sticker on it as a show of commitment.

 

[liveforphysics]

It would be easier to welcome this kind of high power e-bike if it had a license plate and a valid registration sticker on it as a show of commitment.

That licence plate on an ebike only adds a new sharp edge to be cut by when crashing (I've been cut multiple times by licences while off-roading plated bikes). It also impacts the range meaningfully (not a joke how much drag a full sized motorcycle licences plate adds).

Perhaps to be perfectly fair, if road taxes are to pay for the wear and tear that vehicle imposes on the public infrastructure, it could be argued to be a fair rate of taxing an ebike to use them, yet I doubt the real cost of damage to the roads could be exceeding a few pennys a year at most relative to the ~2000-80,000lbs fleet of multi-hundred HP vehicles traveling at high speeds, and certainly well under the administrative costs of processing the transaction and issuing the plate that when mounted will then impose a meaningful impact on the vehicles range, efficiency and lifetime environmental impact.

We are sharing agreement that damaging awesome trails needlessly is a bad idea for everyone who enjoys them, yet it's possible to ride even a 70hp full blown electrical motorcycle though many mt bike trails and do no more damage than wrinkling some leafs on the ground if you're a thoughtful rider. Nor does it require speeding dangerously at poor times to do so anymore than the gas pedal in a fast car forces them to drive recklessly.

The last thing the worlds lowest human moving form of transportation needs is more red-tape and fees to hinders it's adoption as an alternative from multi-ton carcinogenic toxin sprayers.

I do respect your opinion though, and I share your respect of the trails staying as nice as you found them. We have so many amazing local trails here in the SC mountains, I often bring an empty backpack and do litter picking up runs, and even though the bike has 5kW, I ride fast but smooth and gentle without any intended rear wheel spin (likely less than when I'm pumping hard on a non-ebike). Because it's a light carbon ebike and I'm 170lbs body mass, now it's lower vehicle inertial loads on the trail and lower PSI footprint (for a given size tire) as I used to weigh even if it were on a pedal-only bike that weighed 0lbs.

ATB,
-Luke

 

[Powervelocity.com]

I actually pedal this thing when I feel like. I think it's a feature that's worth keeping. I will probably be adding a pedal sensor with variable load regulator. I try not to abuse anything that doesn't belong to me. I do abuse a lot of things that are legally mine, as you can figure out.

 

[Chalo]

I didn't mention it yet, but your build is clean and capable looking and I bet it'll do fine the way it is. It's remarkable how many batteries you managed to cram in. As for your front wheel, those have it really easy compared to rears, and they're inherently stronger.

 

[skeetab5780]

This certainly solves the range anxiety issues. What does that beats weigh with that much battery?

TBH I never feel I have enough battery and I hate it, But I think my ideal battery would be like 1.5-2kw

Very nice clean build. I almost got one of those frame kits. How does it ride?

 

[Powervelocity.com]

I've built a dozen of bikes on this frame and I've sold quite a few bare frames. Battery space was what hooked me up on this frame in the first place. It maybe not as high-end as $1000-3000 frames but it fits the bill as a platform for high performance builds. My first builds were completely clean - everything inside: battery, controller, charger, wiring. Then I ended up expanding the pack for more mileage, and the controller needed more cooling, so I started installing it under the frame. Painted with matching color, it still looks good like it's not there.

It rides pretty smooth. I can go 50 mph without much fear that I had when riding an aluminum bike at 35 mph. Good suspension, MC rims and tires, and added weight makes it very stable at high speeds.

I have to figure out how to weigh it. Will post the results.

Here is 2.3kWh 88v(100v) 26Ah pack I've built earlier for this frame. It's good for 40 miles cruising or 30 miles of hard riding.



And here is an early light version, bicycle wheels, small battery. Very agile and lightweight, like 80lbs or so. I liked how smooth and quiet it rode on those slick tires but I was getting flats after flats, so, finally, went with moto setup.

This certainly solves the range anxiety issues. What does that beats weigh with that much battery?

TBH I never feel I have enough battery and I hate it, But I think my ideal battery would be like 1.5-2kw

Very nice clean build. I almost got one of those frame kits. How does it ride?

 

[migueralliart]

I'm building one of these frames and purchased from powervelocity.com

His support has been phenomenal and very straightforward. Right now I'm waiting on my front 19" wheel and rear 19" MXUS 4T that I purchased. I'm picking up an HS4065 with lyen 18 fet this weekend which I might try out with this frame in the meantime.

I'll start a thread soon.

The battery compartment is what made me purchase it. I'm putting a 18650 GA pack still undecided if I should go 14S10P or 20S7P .. we'll see.


If anybody has any recommendations regarding brakes that fit with MXUS in the rear that'll help.

 

[1KW]

I just purchased the same frame, will be using qs 205/24s16ah lips/18fet from power velocity once my next check clears. Cheers

 

[John in CR]

While a bigger motor will help some with the heat issue, with sealed and stock form, the best thing is to use the smallest wheel you can live with on the hubbie. Compared to a 26" OD wheel a motor in a 20" wheel will make about 50% less heat for the same speed and performance. While a 20" OD may be a bit small, I've got a 16" mag wheel with a nice fat tire that ends up a 22" OD that looks nice on the Enduro frame I got from you...sorry not ready for pics yet. While a 20" may be too small for most, there are options in between. Less heat means greater efficiency and range. With good tuning you can increase performance and efficiency, and also decrease motor heat. Only if an ebike used for pedal first and electric as assist can the negatives of a smaller wheel outweigh the gain.

Also note that with 3 phase higher Kv hubbies it's even more important to stay further away from the controller voltage limit using 24s packs. They are a more difficult load for controllers, and good engineering practice means staying away from 24s packs even with easier to drive motors despite how common it is on ES with guys trying to go fast with motors that are too slow. No EE worth a salt would design a system with 100V component limits to run near 100V.

 

[Brake]

Holy shot Batman. Nice job. That battery is awesome.

 

[Powervelocity.com]

Thanks, John. I do like to pedal now an then, and 17'' with shinko 3'' making the OD 24'' seems like the way to go, not too far off your 22'' OD wheel. I understand the benefits of a smaller wheel I'll probably try going 16'' or even 14'' some time in the future.

As for the voltage, I feel like 24s is a good all-around voltage for high performance builds, and probably even 28s. Yes, at this point for most controllers (that use 4410 fets) it will be pushing it, so going with 4115 fets or better will easily (and cheaply) mitigate these concerns. Higher voltage gives me good speed reserve on commonly available motors. Also, higher voltage generally means you need to push fewer amps to get to the same kw equivalent, so less heat, more efficiency to gain, right? Of course, I agree over engineering and leaving at least 20% safety margin is always a good idea.

While a bigger motor will help some with the heat issue, with sealed and stock form, the best thing is to use the smallest wheel you can live with on the hubbie. Compared to a 26" OD wheel a motor in a 20" wheel will make about 50% less heat for the same speed and performance. While a 20" OD may be a bit small, I've got a 16" mag wheel with a nice fat tire that ends up a 22" OD that looks nice on the Enduro frame I got from you...sorry not ready for pics yet. While a 20" may be too small for most, there are options in between. Less heat means greater efficiency and range. With good tuning you can increase performance and efficiency, and also decrease motor heat. Only if an ebike used for pedal first and electric as assist can the negatives of a smaller wheel outweigh the gain.

Also note that with 3 phase higher Kv hubbies it's even more important to stay further away from the controller voltage limit using 24s packs. They are a more difficult load for controllers, and good engineering practice means staying away from 24s packs even with easier to drive motors despite how common it is on ES with guys trying to go fast with motors that are too slow. No EE worth a salt would design a system with 100V component limits to run near 100V.

 

[macribs]

You got the real estate so why not load em up? Sure you don't need to worry about range anymore

 

[John in CR]

Thanks, John. I do like to pedal now an then, and 17'' with shinko 3'' making the OD 24'' seems like the way to go, not too far off your 22'' OD wheel. I understand the benefits of a smaller wheel I'll probably try going 16'' or even 14'' some time in the future.

There's not a lot of tire selection in 14's, and you end up with right around 20" OD wheel, which is nice, but with common 205mm motors the short spoke lengths are problematic so go with a mag wheel if possible. 16's are common enough that the smaller tires sizes can get you as small a 20"OD. Comparisons with different motors lose validity. I'll be running 27kw peak input or higher like I did before with a 19.25" OD wheel, but as of this morning the total load my motor will be pushing has decreased by 75lbs, so I won't be running at any higher system stress.

As for the voltage, I feel like 24s is a good all-around voltage for high performance builds, and probably even 28s. Yes, at this point for most controllers (that use 4410 fets) it will be pushing it, so going with 4115 fets or better will easily (and cheaply) mitigate these concerns. Higher voltage gives me good speed reserve on commonly available motors. Also, higher voltage generally means you need to push fewer amps to get to the same kw equivalent, so less heat, more efficiency to gain, right? Of course, I agree over engineering and leaving at least 20% safety margin is always a good idea.

High voltages are fine with the right controller, but when the most experienced EE's on the forum strongly caution against running 24s with 100v max controllers, I listen. Running at rated current with 24s is what blew DoctorBass's first Adappto, and after repair they told him to use 20s at the most.

Higher voltage doesn't work in your favor in terms of efficiency. Motor current and voltage, and battery current and voltage, are different animals. Regardless of the pack voltage, the same motor will require the same phase current and apparent voltage for a given torque and rpm, so it will have identical efficiency. When the pack voltage is higher, then the controller has to step down the voltage by a greater %, which has greater losses. Any efficiency gain occurs with hubmotors (because they're run at relatively low rpm, so rpm dependent losses are less significant), when you increase the voltage and decrease the wheel size, since it reduces motor torque requirement (motor current) for the same forward thrust resulting in lower copper losses in the motor.

 

[beast775]

Thats a great way to fill the space in these frames , im guessing you will be trail blazing alot on this ride, would some dense foam on string 1-3-5-7-9-11 take up any play at the battery end where it rests on the box flat ? to keep stress-shifting off your strings, nice mileage monster.

 

[fechter]

Wow, that's a lot of battery. You could jump start a Tesla with that.
There are lots of household appliances that would run fine directly off that battery (about anything with a switching power supply).
You could install a standard 120v outlet on the bike for fun. That could be handy for overnight camping trips.

 

[Powervelocity.com]

Yep, I've installed 110v outlet on my other bike before. Works great for laptops and other devices.

Wow, that's a lot of battery. You could jump start a Tesla with that.
There are lots of household appliances that would run fine directly off that battery (about anything with a switching power supply).
You could install a standard 120v outlet on the bike for fun. That could be handy for overnight camping trips.

 

[Powervelocity.com]

There is no play at all. I've built all kinds of packs and have gone through a few iterations of perfecting the pack building process. This current pack is as solid as a brick, no chafing or any movement between cells, and there is a very thin layer of padding between all strings, not just some of them. Yeah, it's heavy, and there is a certain amount of pressure exerted on the cells that are at the very bottom. It's not huge though because the pack is split in two equal bricks that are placed alongside each other. The pressure on the very bottom cells is approximately only the weight of 11 cells sitting on top (approximately 1lb). There is also some extra padding on the bottom and sides of the pack where it comes in contact with the frame. The length of the two cells are 65mm x 2 = 130mm, plus a few mm for connection, insulation, shrink wrap, etc, for the total of 139mm. The frame width is 140mm. As you can see, it's a very close fit for the frame, almost exact, so there is really no lateral movement for the battery, it's snugly clamped from both sides by frame covers.

Thats a great way to fill the space in these frames , im guessing you will be trail blazing alot on this ride, would some dense foam on string 1-3-5-7-9-11 take up any play at the battery end where it rests on the box flat ? to keep stress-shifting off your strings, nice mileage monster.

 

[Powervelocity.com]

The basic premise of using higher voltage is reduction of heat losses in conductors (copper). If P(lost)=I^2 R holds true, doubling the current will result in quadruple heat losses, and, conversely, reduction of current will decrease the heat losses by 4x. To maintain the same power output levels, however, we will to get it from somewhere and that comes from the increase in voltage. In a nutshell, high current is inherently better suited for heating and high voltage is good for mechanical work. That's why electric cars use high voltage (I think Porsche, for example, went as high as 800v recently). I know that most ebike controllers will blow above 95v, but that's the reason I am not using them.

Thanks, John. I do like to pedal now an then, and 17'' with shinko 3'' making the OD 24'' seems like the way to go, not too far off your 22'' OD wheel. I understand the benefits of a smaller wheel I'll probably try going 16'' or even 14'' some time in the future.

There's not a lot of tire selection in 14's, and you end up with right around 20" OD wheel, which is nice, but with common 205mm motors the short spoke lengths are problematic so go with a mag wheel if possible. 16's are common enough that the smaller tires sizes can get you as small a 20"OD. Comparisons with different motors lose validity. I'll be running 27kw peak input or higher like I did before with a 19.25" OD wheel, but as of this morning the total load my motor will be pushing has decreased by 75lbs, so I won't be running at any higher system stress.

As for the voltage, I feel like 24s is a good all-around voltage for high performance builds, and probably even 28s. Yes, at this point for most controllers (that use 4410 fets) it will be pushing it, so going with 4115 fets or better will easily (and cheaply) mitigate these concerns. Higher voltage gives me good speed reserve on commonly available motors. Also, higher voltage generally means you need to push fewer amps to get to the same kw equivalent, so less heat, more efficiency to gain, right? Of course, I agree over engineering and leaving at least 20% safety margin is always a good idea.

High voltages are fine with the right controller, but when the most experienced EE's on the forum strongly caution against running 24s with 100v max controllers, I listen. Running at rated current with 24s is what blew DoctorBass's first Adappto, and after repair they told him to use 20s at the most.

Higher voltage doesn't work in your favor in terms of efficiency. Motor current and voltage, and battery current and voltage, are different animals. Regardless of the pack voltage, the same motor will require the same phase current and apparent voltage for a given torque and rpm, so it will have identical efficiency. When the pack voltage is higher, then the controller has to step down the voltage by a greater %, which has greater losses. Any efficiency gain occurs with hubmotors (because they're run at relatively low rpm, so rpm dependent losses are less significant), when you increase the voltage and decrease the wheel size, since it reduces motor torque requirement (motor current) for the same forward thrust resulting in lower copper losses in the motor.

 

[John in CR]

Using higher voltage to reduce I2R losses for the same power only applies between the battery and controller. Regardless of pack voltage for the same torque and rpm (power) the motor gets the same thing from the controller. Our controllers are buck converters to change the DC coming from the battery to exactly what our motor needs. I use higher than necessary voltage for a different reason than you plan, to get higher torque (greater acceleration) all the way through my usual top cruising speeds. That higher performance resulting from higher torque does have a cost in terms of more motor heat, but riding around using the same performance I would with a lower pack voltage has no cost in motor heat. There is more heat in the controller though, which warrants using a beefier controller like you plan. There's some interesting discussion on this topic here https://endless-sphere.com/forums/viewtopic.php?f=30&t=79229.

 

[beast775]

Thanks for the explanation powervelocity, i had the string minus battery go the way i didnt expect-towards the front when my battery was a bit tilted, cant wait to get better at understanding torque

 

[Powervelocity.com]

If there is no benefit in higher voltage, we should be all getting 12v packs with 1000A discharge rates and be happy with all the torque we can get from it.
I will choose my 24s over 20s or 18s in a heartbeat, as the difference in performance is substantial.
And I have no concerns overheating my 18Fet controller running at 100v and 100Amps. The motor MXSUS v2, however, does overheat after 3 minutes running at 9kw but that's expected as that's 3x of its rated power.

Using higher voltage to reduce I2R losses for the same power only applies between the battery and controller. Regardless of pack voltage for the same torque and rpm (power) the motor gets the same thing from the controller. Our controllers are buck converters to change the DC coming from the battery to exactly what our motor needs. I use higher than necessary voltage for a different reason than you plan, to get higher torque (greater acceleration) all the way through my usual top cruising speeds. That higher performance resulting from higher torque does have a cost in terms of more motor heat, but riding around using the same performance I would with a lower pack voltage has no cost in motor heat. There is more heat in the controller though, which warrants using a beefier controller like you plan. There's some interesting discussion on this topic here https://endless-sphere.com/forums/viewtopic.php?f=30&t=79229.

 

[John in CR]

Of course there's a performance advantage using higher voltage, which is a different topic. The point I was making is that for a given rpm and torque a given motor gets the same signal from a controller regardless of pack voltage. It may be broken up into different size pulses due to pwm, but what the motor "sees" is a relatively constant supply. That means we don't get a benefit in the form of reduced I2R losses by using higher voltage for the same power. Yes, power input is volts X amps, but volts and amps have to be looked at separately...current for torque (acceleration/thrust) and voltage for rpm (speed, though there's a torque component with speed since the load of overcoming wind resistance increases geometrically.)

Regarding promoting the use of 100V limit equipment with packs that are 100V fresh off the charge, regardless of anecdotal evidence of people getting away with it, it should be discouraged. Those who get away with it are pushing light loads and use easy to drive motors, but even then failures are too common, and no one pushing real performance has gotten away with it without popping plenty of controllers. Since you're a vendor I'm trying to do you a favor. We've had only one vendor on ES who promoted the use of 24s packs with 100V limit components in the controllers, and he quickly went out of business. Absolute reliability is pretty easy even at extreme performance, and that is accomplished best by staying well away from current and voltage limits of any component in the system.

If there is no benefit in higher voltage, we should be all getting 12v packs with 1000A discharge rates and be happy with all the torque we can get from it.
I will choose my 24s over 20s or 18s in a heartbeat, as the difference in performance is substantial.
And I have no concerns overheating my 18Fet controller running at 100v and 100Amps. The motor MXSUS v2, however, does overheat after 3 minutes running at 9kw but that's expected as that's 3x of its rated power.

Using higher voltage to reduce I2R losses for the same power only applies between the battery and controller. Regardless of pack voltage for the same torque and rpm (power) the motor gets the same thing from the controller. Our controllers are buck converters to change the DC coming from the battery to exactly what our motor needs. I use higher than necessary voltage for a different reason than you plan, to get higher torque (greater acceleration) all the way through my usual top cruising speeds. That higher performance resulting from higher torque does have a cost in terms of more motor heat, but riding around using the same performance I would with a lower pack voltage has no cost in motor heat. There is more heat in the controller though, which warrants using a beefier controller like you plan. There's some interesting discussion on this topic here https://endless-sphere.com/forums/viewtopic.php?f=30&t=79229.