My CB360 Emoto Build (and some battery questions)

[Tylor]

Hi all, I just found the forum and I love the community here, this is my first post please let me know if I am doing anything wrong.

I wanted to share the progress on my CB360 build, first some information:
Body:
- 1974 CB360 frame
- upgraded front disk break
- 1999 Yamaha FZR600R swingarm (to fit the larger rear wheel and slightly lengthen the bike)
- All the lights / wiring / switches are new with custom fused 12v system
- Custom carbon fiber seat pan with faux leather upholstery
- Lots of small 3d printed parts / brackets

Powertrain:
- 12kW 17" QS motor
- Kelly KLS 96601-8080H controller
- 400A contactor / fuse system with pre-charge bypass

I haven't built the battery yet, I have designed several packs using different cells but have not decided on a final design. Firstly the constraints:
- Size, I would like to not have to modify the structural parts of the frame, which gives me approx. 15" x 15" x unbounded. (not square, see pictures)
- Voltage, I am aiming for 96-120V battery, with a nominal voltage >96V and fully charged max at 120V.
- Cost, budget build I would like to keep the battery under $1500 w/ BMS and charger.
- Capacity, I want the bike to be a city commuter, I don't need it to have crazy range I want a minimum of 40 miles range with conservative driving (no 0-100 pulls).
- Current, this is where I need your help the most, I have done lots of reading here and across the internet, and I am a little confused on how much current I should design my battery to supply. I would like to be able to supply as much current is necessary to give the bike good acceleration and top speed. Kelly's manual rates the KLS96601-8080H at 600A peak (30 seconds) and 240A continuous. I think I have gathered from this forum that that is phase amps, and that that exceeds what is necessary for the motor? The manual also says the controller can do "current multiplication" where by reducing voltage it can increase current. How much current does my battery need to supply?

I have looked at lots of different cells (mostly battery hookup) SPIM08HP / Headway / LiFePo4 Prismatic / NMC ... and more. Right now I am looking at these BMW NMC packs because with 3 of them, reconfigured to 30s I will get approx. 45ah 115V but they are rated to only supply 75A continuous and 300A peak, is that enough? I hope you guys can give me some insight here.

Anyways here's some pictures:

Old picture good profile view

Cardboard mock up of 3x BMW packs like described above

Old pic from testing lights

Some laser cut steel parts (left is to fit swingarm to wheel, and right is to fit rear suspension to swingarm)

Slightly newer pic of the build (pls ignore mess)

Excited to hear your thoughts!

 

[TorgueRPM]

Is the fzr swingarm a direct fit? I've got a non-running CB360 cafe racer sitting in my garage that I've been eyeing up.

As for current, use the ebikes.ca motor simulator. If you know the kv of the motor, you can play around with different loads and voltages to figure out how much continuous and peak current you want for your desired cruising speed

 

[Tylor]

Is the fzr swingarm a direct fit? I've got a non-running CB360 cafe racer sitting in my garage that I've been eyeing up

No, its too wide at the pivot bearing race, cut down the ends, replace the bearings, and lathe some pipe to fit perfect as a spacer between the OEM CB360 axle and the FZR swingarm race. Described well here

 

[amberwolf]

Powertrain:
- 12kW 17" QS motor
- Kelly KLS 96601-8080H controller
- 400A contactor / fuse system with pre-charge bypass

- Voltage, I am aiming for 96-120V battery, with a nominal voltage >96V and fully charged max at 120V.

- Capacity, I want the bike to be a city commuter, I don't need it to have crazy range I want a minimum of 40 miles range with conservative driving (no 0-100 pulls).

Capacity needed for a range depends on power usage, usually defined as wh/mile (or wh/km). This in turn depends on your speed, riding conditions, winds, road conditions vs tires etc.

If you define the job the bike needs to do for you and the specific conditions it has to do that job under, you can use simulators and calculators online, such as the ebikes.ca motor / trip simulators, to guesstimate the power usage for specific scenarios, and guesstimate wh/mile. It's designed for ebikes vs motorcycles, but you can still use it, by using the custom features with guesstimates of the characteristics of the parts you have (motor, controller, battery).

If you don't want to go into all that, you can just guesstimate 150-200wh/mile usage, and probably end up with better than that in reality if you ride on flat roads with little wind. (if you have hills/winds, you should try the simulators to get estimates, as usage could greatly exceed this basic guesstimate and then your battery will be too small).

If you have 200wh/mile usage, then for 40 miles that's 8000wh (8kwh) of capacity minimum. Since there will be loss of capacity as it ages, I'd recommend adding at least 25% to that so you still have minimum range required even after it's aged a fair bit.

If you need that minimum range to get to a specific place via some direct route under ideal conditions, then you should add another 25% capacity or more to allow for detours and headwinds or other adverse conditions that increase your usage and shorten your range.

- Current, this is where I need your help the most, I have done lots of reading here and across the internet, and I am a little confused on how much current I should design my battery to supply. I would like to be able to supply as much current is necessary to give the bike good acceleration and top speed. Kelly's manual rates the KLS96601-8080H at 600A peak (30 seconds) and 240A continuous. I think I have gathered from this forum that that is phase amps, and that that exceeds what is necessary for the motor? The manual also says the controller can do "current multiplication" where by reducing voltage it can increase current. How much current does my battery need to supply?

Do you intend to use the maximum phase amps? (best for quick acceleration) If so, then if you are using the highest multiplication factor in the settings (you'd need to check what that will be), you divide the max phase amps by that factor to get the battery current needed to create those phase amps.

Made up numbers as example: 600Aphase / MF1.5, = 400A battery current.

So your battery would have to be built and sized to supply *at least* 400A current with minimal voltage sag (the more sag, the less total power the motor gets, and the more power is wasted as heat inside the battery, bad for everybody), for as long as the controller can draw that much current.

It would only have to sustain the 240Aphase / MF ; let's say that's 1.5, so 160A continuous...but you still have to size it and construct it for the worst case conditions. If you build it only to handle the continuous, then every peak hit will be pretty hard on it, and it won't perform as well as it could, or last as long if those peaks are frequent (like stop/start traffic) or sustained (like hills or acceleration on freeways, etc).

Also, if you don't know how much power the system will actually draw under your specific conditions, it's hard to predict how much current will be actually used, or for how long at any particular time. it could be that you wont' see hardly any current most of the time (except during acceleration or hill climbing or high speeds), but you'd have to do calculations or simulations to better tell about that.


BTW, you should check if the controller autoprotects itself after those 30 seconds, autoreducing current to the continuous rating, or if it requires *you* to do this. If it is not automatic, then you risk controller destruction by exceeding whatever conditions that limit is meant to protect against (overheating, etc) and should setup a way to monitor whatever that is, so you can be sure never to do this. It's probably automatic...but as a general rule, controller firmware (and hardware) engineers for these companies are not exactly the most brilliant safety designers (etc), based on stuff we see around here.

I have looked at lots of different cells (mostly battery hookup) SPIM08HP / Headway / LiFePo4 Prismatic / NMC ... and more. Right now I am looking at these BMW NMC packs because with 3 of them, reconfigured to 30s I will get approx. 45ah 115V but they are rated to only supply 75A continuous and 300A peak, is that enough? I hope you guys can give me some insight here.

It sounds like you may need at least twice as much battery as you're planning on, to handle the possible continous power requirements, but that depends on your actual conditions, as noted above.

The other thing you'll need to know about is how much capacity you actually require. 45Ah at 96v (nominal) is only about 4.3kwh, which might be enough for 40 miles if your wh/mile usage is low (100wh/mile or less), but not if it's high.

 

[Tylor]

Capacity needed for a range depends on power usage, usually defined as wh/mile (or wh/km). This in turn depends on your speed, riding conditions, winds, road conditions vs tires etc.

If you define the job the bike needs to do for you and the specific conditions it has to do that job under, you can use simulators and calculators online, such as the ebikes.ca motor / trip simulators, to guesstimate the power usage for specific scenarios, and guesstimate wh/mile. It's designed for ebikes vs motorcycles, but you can still use it, by using the custom features with guesstimates of the characteristics of the parts you have (motor, controller, battery).

If you don't want to go into all that, you can just guesstimate 150-200wh/mile usage, and probably end up with better than that in reality if you ride on flat roads with little wind. (if you have hills/winds, you should try the simulators to get estimates, as usage could greatly exceed this basic guesstimate and then your battery will be too small).

If you have 200wh/mile usage, then for 40 miles that's 8000wh (8kwh) of capacity minimum. Since there will be loss of capacity as it ages, I'd recommend adding at least 25% to that so you still have minimum range required even after it's aged a fair bit.

If you need that minimum range to get to a specific place via some direct route under ideal conditions, then you should add another 25% capacity or more to allow for detours and headwinds or other adverse conditions that increase your usage and shorten your range.



Do you intend to use the maximum phase amps? (best for quick acceleration) If so, then if you are using the highest multiplication factor in the settings (you'd need to check what that will be), you divide the max phase amps by that factor to get the battery current needed to create those phase amps.

Made up numbers as example: 600Aphase / MF1.5, = 400A battery current.

So your battery would have to be built and sized to supply *at least* 400A current with minimal voltage sag (the more sag, the less total power the motor gets, and the more power is wasted as heat inside the battery, bad for everybody), for as long as the controller can draw that much current.

It would only have to sustain the 240Aphase / MF ; let's say that's 1.5, so 160A continuous...but you still have to size it and construct it for the worst case conditions. If you build it only to handle the continuous, then every peak hit will be pretty hard on it, and it won't perform as well as it could, or last as long if those peaks are frequent (like stop/start traffic) or sustained (like hills or acceleration on freeways, etc).

Also, if you don't know how much power the system will actually draw under your specific conditions, it's hard to predict how much current will be actually used, or for how long at any particular time. it could be that you wont' see hardly any current most of the time (except during acceleration or hill climbing or high speeds), but you'd have to do calculations or simulations to better tell about that.


BTW, you should check if the controller autoprotects itself after those 30 seconds, autoreducing current to the continuous rating, or if it requires *you* to do this. If it is not automatic, then you risk controller destruction by exceeding whatever conditions that limit is meant to protect against (overheating, etc) and should setup a way to monitor whatever that is, so you can be sure never to do this. It's probably automatic...but as a general rule, controller firmware (and hardware) engineers for these companies are not exactly the most brilliant safety designers (etc), based on stuff we see around here.







It sounds like you may need at least twice as much battery as you're planning on, to handle the possible continous power requirements, but that depends on your actual conditions, as noted above.

The other thing you'll need to know about is how much capacity you actually require. 45Ah at 96v (nominal) is only about 4.3kwh, which might be enough for 40 miles if your wh/mile usage is low (100wh/mile or less), but not if it's high.

Thanks for the reply!

I haven't found good wh/mile stats online for this motor, maybe somebody on this forum knows about these 12kW QSmotors? Although I imagine there aren't good numbers because of the variance, it is supposed to be capable for sub 3s 0-60mph but obviously doing pulls like that will drain the battery faster. The 40 mile range is including not getting stranded distance, and I am looking at used cells that have already been cycled and lost some capacity but should have the lifetime that I'm looking for.

Q: Do you intend to use the maximum phase amps? A: Yes, I want the acceleration and top speed more than the range >

BTW, you should check if the controller autoprotects itself after those 30 seconds - It says that it does, and if its drawing >400A from the battery it should trip the fuse.

I've designed some battery packs with cells that can deliver more current, (30s Lishen 3.2v 40ah Lifepo4 Prismatic 6C Power Cells) maybe that would be better.

I have also heard mixed things about using supercapacitors, do you think the density of the NMC cells in parallel with a supercap array could help handle the peak current draw? Is that a viable solution or should I avoid it?

Thank you for your feedback!

 

[amberwolf]

I haven't found good wh/mile stats online for this motor,

Wh/mile is not from or for the motor, it's the whole vehicle as used by the specific rider under their specific circumstances.

If you know of another person using a very similar EV in the same circumstances/riding conditions in the same way you are, you can guesstimate your Wh/mile will be similar to theirs...but every difference between you and them means a probable difference in Wh/mile.

It is better if you can use the simulator/etc with your specific vehicle/situation/conditions to get your likely power needs and usage.

Think of Wh/mile as gas mileage, MPG.

Q: Do you intend to use the maximum phase amps? A: Yes, I want the acceleration and top speed more than the range >

I like as quick an acceleration as I can get, but don't really care for speed, and only sometimes need range...so everybody's needs are different.

if its drawing >400A from the battery it should trip the fuse.

The fuse should be sized to protect your wiring/etc from a short that will damage it, so for whatever current the wiring itself can take safely.

The battery should be protected by it's BMS (which should be set well below what the cells and interconnects can handle) and/or by the controller's limits being setup / designed to be below what the BMS protection limits or max current capabilities are. (the "or" being if the BMS does not have overcurrent protection).

I have also heard mixed things about using supercapacitors, do you think the density of the NMC cells in parallel with a supercap array could help handle the peak current draw? Is that a viable solution or should I avoid it?

Supercaps take up so much space for what you get out of them that you are usually better off using it for more cells. You'd have to do the math for your application and the specific parts you're intending to use to be sure.

If you had a stationary application they might do some good for momentary spikes since weight or volume doesn't usually matter, but vehicles are typically better off with more cells. (or different, bigger or more capable ones).