Electrified BikeE for Comfort and Range

General Discussion about electric bicycles.
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Alan B   100 GW

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Re: BMC powered EbikeE for Comfort and Range

Post by Alan B » Dec 19 2014 9:20pm

When it comes time to make a pack for the bike it certainly should use quality cells.

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Re: EbikeE and BMC for Comfort and Range

Post by Cowardlyduck » Dec 20 2014 6:42pm

Alan B wrote:One thing I've become spoiled with is how nicely the new torque controlled sine wave controllers work. I'd like to try a small one on this BikeE.
I've considered getting a sine-wave also. Mainly to eliminate all noise. The noise even though low, is the biggest give away my bike is electric. If I did get one it would just be a cheap 6 or 9 Fet one though.
BVH wrote:Hopefully, you're showing the "Trustfire" brand cell just for illustration purposes. The only thing Trustfire cells are famous for is being woefully short on their advertised capacity. Well, I don't want to sell them short - they are also known to vent with flame much easier than other brand cells if used hard. The Sonys/Panasonics will do you proud.
Lol - Yes, your the second person to comment on them. I bought them many years ago for a torch before I had a clue about anything. Yes, they are crap, and only for illustration purposes!

Cheers
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Re: BMC powered BikeE for Comfort and Range

Post by BVH » Dec 20 2014 11:33pm

You mention "torch" - Are you on Candle Power Forums?

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Dec 20 2014 11:47pm

BVH wrote:You mention "torch" - Are you on Candle Power Forums?
I think that was directed at another poster, but I've been active there in the past and still visit there occasionally. It is a good resource for those of us who are flashaholics. :)

In fact the recent photos I've been using in other threads have been illuminated by a Fenix TK75 2600 lumen flashlight powered by quad 18650's, and captured on a 16 megapixel Samsung Note 4 phone. It isn't quite the same as the DSLR and pro lighting setup, but it is quick and more than adequate much of the time.

The sine controller has been shipped. I have some time off after Christmas so perhaps I'll be able to install and test the controller then. I've read that the sine controllers quiet down the gearmotors as much of the gear noise is related to torque pulses from the motor. I'm really looking forward to the gentle and controllable torque throttle.

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Re: BMC powered BikeE for Comfort and Range

Post by Cowardlyduck » Dec 21 2014 10:21pm

I had written another longer post but lost it when my laptop battery died suddenly, so Ill keep this short.
BVH wrote:You mention "torch" - Are you on Candle Power Forums?
No
Alan B wrote: I'm really looking forward to the gentle and controllable torque throttle.
This is something I hadn't considered. I might wait for Addaptto to release there Micro-E and get one when I get my MiniE for my Fighter. That way I can stop dangerously flipping this thing. :lol:

Cheers
High Power LiPo wiring harnesses - 4P - XT90, HXT4mm, 5.5mm. 200Amp+ capable. Global shipping.

Modified Stealth Fighter - Force air cooled motor @ 6KW, Adaptto Mini-E. 49AH, 52V 18650 - 2.5Kwhr
Cowardlyducks - Stealth Fighter Videos

BikeE recumbent commuter - 9C, 6Fet Grinfineon, internal 17AH, 52V, + on-board solar.

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Re: BMC powered BikeE for Comfort and Range

Post by Cowardlyduck » Jan 14 2015 4:16am

How's the Bike-E battery re-work coming along Alan?
Jumping back on my Bike-E after a long Christmas break has left me wanting far more from it...lots of little things to fix up/do and consider for the future. :)

Cheers
High Power LiPo wiring harnesses - 4P - XT90, HXT4mm, 5.5mm. 200Amp+ capable. Global shipping.

Modified Stealth Fighter - Force air cooled motor @ 6KW, Adaptto Mini-E. 49AH, 52V 18650 - 2.5Kwhr
Cowardlyducks - Stealth Fighter Videos

BikeE recumbent commuter - 9C, 6Fet Grinfineon, internal 17AH, 52V, + on-board solar.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Jan 14 2015 12:13pm

Nothing to report here, too many projects. I got a new workbench, but so far all the projects on it are amateur radio related. The Borg is the daily driver, and it needs some attention first, the BikeE is down the list a bit. Did get a new sinewave controller for the BikeE, looking forward to trying that. The sinewave torque throttle controller on the Borg gives such silky smooth control it is really a pleasure to ride.

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Re: BMC powered BikeE for Comfort and Range

Post by Cowardlyduck » Jan 15 2015 4:46am

Alan B wrote:Nothing to report here, too many projects. I got a new workbench, but so far all the projects on it are amateur radio related. The Borg is the daily driver, and it needs some attention first, the BikeE is down the list a bit. Did get a new sinewave controller for the BikeE, looking forward to trying that. The sinewave torque throttle controller on the Borg gives such silky smooth control it is really a pleasure to ride.
Fair enough. I too am very busy and only manage to do very minimal things. Last night I spent the whole evening just getting my CA power limit button working...now I can instantly limit to 200W when needed. :P

I was toying with the idea of getting an Adaptto Micro sine wave controller + display once they are released. I'll have to wait and see though. My funds are very tight for ebike stuff and I think the new 18650 battery will need to take priority first.

Speaking of which I'm finding I really don't want/need to go any faster than my current top speed of around 40kph. So I think I might aim for a 12S8P 18650 pack like you instead of the 18S6P pack I was previously entertaining.
At 12S ~45V Nominal, I should still be able to hit 38kph with a 2.4" tire at 100% throttle. I will then program 120% throttle to the 3rd speed setting on my controller for those times I want 45+kph. :mrgreen:

Cheers
High Power LiPo wiring harnesses - 4P - XT90, HXT4mm, 5.5mm. 200Amp+ capable. Global shipping.

Modified Stealth Fighter - Force air cooled motor @ 6KW, Adaptto Mini-E. 49AH, 52V 18650 - 2.5Kwhr
Cowardlyducks - Stealth Fighter Videos

BikeE recumbent commuter - 9C, 6Fet Grinfineon, internal 17AH, 52V, + on-board solar.

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Re: EbikeE and BMC for Comfort and Range

Post by erik_m » Jan 23 2015 10:49pm

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Last edited by erik_m on Feb 01 2015 2:04am, edited 1 time in total.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Jan 24 2015 11:42pm

I had originally planned 18S Lipo also, but started with 12S for simplicity. It has worked so well I've not really been motivated to go higher, and now with the voltage limit of the ebikes.ca sinewave controller I will stick with 12S. It is nice to be able to balance charge the whole 12S at once. :)

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Mar 23 2016 11:11pm

The BikeE project is about to get a jolt. At the moment it still looks like this:

Image

But a new battery is on the way:

Image

This will liven up the bike a bit. The pack now is 12S 44/50V 16AH. So the watt hours of these two packs is nearly the same, but the voltage will be up a little which will raise the top speed slightly. I also have a sinewave controller to put on, so that might lower it a bit, hard to say.

The new pack is 52 volts of 18650 goodness 14S4P 13.5AH 58.8V rated to 30A continuous. The question is, should I mount this on the top of the beam?

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Re: BMC powered BikeE for Comfort and Range

Post by Cowardlyduck » Mar 23 2016 11:16pm

Cool stuff Alan.
Why not try mounting it behind the seat. That way you might even be able to keep your current batteries and have epic range abilities. :)

Cheers
High Power LiPo wiring harnesses - 4P - XT90, HXT4mm, 5.5mm. 200Amp+ capable. Global shipping.

Modified Stealth Fighter - Force air cooled motor @ 6KW, Adaptto Mini-E. 49AH, 52V 18650 - 2.5Kwhr
Cowardlyducks - Stealth Fighter Videos

BikeE recumbent commuter - 9C, 6Fet Grinfineon, internal 17AH, 52V, + on-board solar.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Mar 24 2016 12:01am

Cowardlyduck wrote:Cool stuff Alan.
Why not try mounting it behind the seat. That way you might even be able to keep your current batteries and have epic range abilities. :)

Cheers
Thanks for the suggestion, I'll look at that option. I had originally six of the Zippy 6S 8AH batteries onboard, but I found the range was excessive and they were constraining the forward motion of the seat so I took some out. I do have some pannier mounts for extended packs. What would really be nice is to get a few more cells inside the beam, how's that going?

If I put T nuts into the beam top, I wonder if that will preclude from putting cells inside. Need to consider all the ramifications...

I'm reviewing the BAC500+ that I have, it is much smaller than the 12 FET Lyen that's on the rear as well, that will free up some space. Would like to mount the Topeak rack on there too. Lots to look into!

Edit - I see that your in-beam BikeE 12S5P pack is 60 cells, a 14S4P pack would be 56 cells, so certainly possible. 4P would be slightly easier to set up, though either should be no problem. So an in-beam pack could be the same size as this Shark pack for a nice range doubling. It would look like a 700WH ebike but it would be a 1400WH sleeper. :)

I just need to build myself a battery welder. Looking forward to it.

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Re: BMC powered BikeE for Comfort and Range

Post by StudEbiker » Mar 24 2016 1:36am

I had one of those types of packs for awile and thought about using on the Bike E. If I had used it, I would have put it i. front of the seat on top of the rail. It was very tempting, but I eventually went in a different direction because at the time I think those packs were only available in 36v configuration.

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Re: BMC powered BikeE for Comfort and Range

Post by Cowardlyduck » Mar 24 2016 1:56am

Yeah, if you will never use the extra range, then I guess there's no point as it's just extra weight.

The in-beam (I like that term :lol: ) pack is still yet to fully materialise. I have my 3rd child due any day now, so I honestly don't think I'll get around to building the pack any time soon.
That being said, I'm a little wary that my current LiPo pack will make it through another winter here, so I might need to get a move on in a few months.

In terms of fitting it, you will not be able to do it without completely removing the rear stay bolts. There is barely enough room to fit 2 18650's side-by-side. Staggering gives a little more room, but that should get taken up by padding/heat-shrink. My pack will be 12S5P, so yeah, 60 cells. It will fit, but only just by my calculations leaving about 20-30mm before the first of the rear stay bolts.

I also plan to swap over to using a Phaserunner controller once available. It will fit perfectly inside the rear tail. :)

Cheers
High Power LiPo wiring harnesses - 4P - XT90, HXT4mm, 5.5mm. 200Amp+ capable. Global shipping.

Modified Stealth Fighter - Force air cooled motor @ 6KW, Adaptto Mini-E. 49AH, 52V 18650 - 2.5Kwhr
Cowardlyducks - Stealth Fighter Videos

BikeE recumbent commuter - 9C, 6Fet Grinfineon, internal 17AH, 52V, + on-board solar.

Ebike Garage - My YouTube Ebike ramblings.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Mar 24 2016 2:18am

Cowardlyduck wrote:Yeah, if you will never use the extra range, then I guess there's no point as it's just extra weight.

The in-beam (I like that term :lol: ) pack is still yet to fully materialise. I have my 3rd child due any day now, so I honestly don't think I'll get around to building the pack any time soon.
That being said, I'm a little wary that my current LiPo pack will make it through another winter here, so I might need to get a move on in a few months.

In terms of fitting it, you will not be able to do it without completely removing the rear stay bolts. There is barely enough room to fit 2 18650's side-by-side. Staggering gives a little more room, but that should get taken up by padding/heat-shrink. My pack will be 12S5P, so yeah, 60 cells. It will fit, but only just by my calculations leaving about 20-30mm before the first of the rear stay bolts.

I also plan to swap over to using a Phaserunner controller once available. It will fit perfectly inside the rear tail. :)

Cheers
Yes, that all sounds about right. I found earlier that the extra weight of the batteries that I wasn't really using was annoying when lifting the bike and just getting in the way, but I do want long range capability. So I want battery capacity that is scalable.

A battery inside the beam for normal use at 700WH, and two removable packs at 700WH each would be perfect. The 100 mile rides have a limit of 2000WH so 700WH times 3 is very close to that. So perhaps I'll do the Shark pack first since that is easy and quick, then do an internal pack later, and finally figure out some other configuration for the final 700WH. Could make a tube that looks like a long M@glite and hang it underneath the beam. Make the front of it be a headlight, too. It would have to be a little larger in diameter than a maglite, but 4P is ideal for that kind of mounting. Might look good under there. Perhaps make it look like a rocket assist. It would have about 950mm of battery length (14S) and 4 cells parallel at each level. Not hard to make. That could end up being battery #2 and then the Shark on top of the rail would be battery #3.

There are some nice ideal diode control ICs that will handle these voltages (with external FETs) to combine the packs without them needing to be SOC matched.

If the BAC500+ turns out to be insufficient I'll try the BAC800/PhaseRunner next. This with the BMC V4C in the rear wheel.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Aug 02 2016 10:37am

OK, dusted off the BikeE today and started scheming again. The Zippy 12S16AH pack is still sitting at 4.10V after perhaps a year. I should probably draw it down a little, but amazing balance those Turnigy have.

I'm getting ready to put sinewave control on this bike. :)

There's a BAC500+ that will fit nicely on here. Just need to get the cabling to match up. Plus the 14S 13.5AH battery. It'll be a whole new machine. Maybe dial in a little field weakening but probably not. Don't want to go too fast. This is a relaxed cruising machine.

I should put a Ham Radio on it, a 2 meter or dualband rig. And set things up so I can carry some extra batteries in the panniers under the seat. Then it will go all day long. 14S I've got the 20AH and the 24AH Triangle packs to add to the Shark at 13.5AH. How's 52V at 58AH sound for 3KWH.

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Re: BMC powered BikeE for Comfort and Range

Post by Cowardlyduck » Aug 02 2016 7:18pm

Not sure if it's what your already referring to, but the Phaserunner has dimensions that will let it fit very nicely inside the frame width.

I was very close to buying one, but I started a new project building a Flux Alpha, so need all the spare $$$ for that now.

Cheers
High Power LiPo wiring harnesses - 4P - XT90, HXT4mm, 5.5mm. 200Amp+ capable. Global shipping.

Modified Stealth Fighter - Force air cooled motor @ 6KW, Adaptto Mini-E. 49AH, 52V 18650 - 2.5Kwhr
Cowardlyducks - Stealth Fighter Videos

BikeE recumbent commuter - 9C, 6Fet Grinfineon, internal 17AH, 52V, + on-board solar.

Ebike Garage - My YouTube Ebike ramblings.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Aug 02 2016 11:10pm

Image

I have a BAC 500+ that I'm going to try on this ebike, and dual PhaseRunners on the 2WD Bonanza mountain bike with DD 9C rear hub and BMC front hub.

Should be very interesting in both cases.

I just need to make some adapters for the phase wires and temporarily mount the BAC 500+ and then I can update the firmware and start configuring for the BMC on this BikeE. Hope it works without a lot of trouble, some folks have had many problems getting these to work. But it should be nice when it works.

The BAC 500+ is the earlier version of what became the PhaseRunner. It is 60V limited, or perhaps 75, but I'm planning to run 12 or 14S so that fits fine. It is metal and wider, longer and thinner than the PhaseRunner. But they aren't available anymore, so if it fails I'll move to a PhaseRunner. I think either will fit nicely in the BikeE frame.

One super thing about these is the variable regen, though I won't be able to use that, but on a DD it would be handy, I love that feature on my Borg. It has replaced the rear brake on that bike.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Aug 30 2017 1:51pm

I dug out the BikeE and made a few minor upgrades.

The biggest is changing the front wheel to one with a 70mm drum brake by SA. So far in early testing it runs quiet and low drag when not braking, but the braking forces are not too strong. Perhaps it will break in and improve. The rear rim brakes still screech, need to work on that.

I still want to put a battery internal to the frame as Cowardlyduck has. I'm thinking to make the battery have flexible joints between the parallel blocks to make it easy to install. But first I have to get a battery welder and cells. 14S4P 18650 cells should fit fine. Wonder what's the best cell? Need good capacity and handle 30 amps max.

I also plan to put a PhaseRunner in this bike. I've been testing a pair of them in the Bonanza 2WD and they are awesome.

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Re: BMC powered BikeE for Comfort and Range

Post by Cowardlyduck » Aug 30 2017 5:57pm

Alan B wrote:I still want to put a battery internal to the frame as Cowardlyduck has. I'm thinking to make the battery have flexible joints between the parallel blocks to make it easy to install. But first I have to get a battery welder and cells. 14S4P 18650 cells should fit fine. Wonder what's the best cell? Need good capacity and handle 30 amps max.

I also plan to put a PhaseRunner in this bike. I've been testing a pair of them in the Bonanza 2WD and they are awesome.
Awesome! I'm glad I've inspired!
If you went with Sanyo/Panasonic 3.5AH GA cells you could pull that 30A, however they do sag quite a bit under anything more than 5A per cell. I'm finding my 14S5P setup is sagging around 4-5V under 1250W load and if I run the battery all the way down with my power set that high I loose around 30% capacity. Running at 750W the 5P is much happier, sag is only 2-3V and I get 15-16AH of my theoretical 17.5AH.
On 14S I get well over 50Kph all through the discharge which is a bit fast TBH, so I'm actually thinking about swapping out my 2S5P auxiliary pack with a 12S1P pack to give me a 12S6P battery. This would give me a more sensible top speed of 40kph+ and increase my range well over 25% due to the top speed decrease and extra parallel cell.

If you do decide to stick with 4P, you might want to consider one of the higher output LG or Samsung 3-3.2AH cells, but you won't have as much capacity then so it's a trade off.

Love that your going with the PhaseRunner. I was very close to doing the same, but in the end I didn't really need it, couldn't justify the cost, and I'm happy with my 6Fet Grinfineon anyway.

Looking forward to seeing someone else attempt the internal battery, and I hope the lessons from my attempt help you out. :)
I'm assuming you saw the video I posted on the build process.
https://youtu.be/JM3Sqll5n00

Cheers
High Power LiPo wiring harnesses - 4P - XT90, HXT4mm, 5.5mm. 200Amp+ capable. Global shipping.

Modified Stealth Fighter - Force air cooled motor @ 6KW, Adaptto Mini-E. 49AH, 52V 18650 - 2.5Kwhr
Cowardlyducks - Stealth Fighter Videos

BikeE recumbent commuter - 9C, 6Fet Grinfineon, internal 17AH, 52V, + on-board solar.

Ebike Garage - My YouTube Ebike ramblings.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Aug 30 2017 7:03pm

Your build was educational, and made me consider how to avoid the issues you faced. I will look at 5P, 4P is pretty short so perhaps 5P is do-able. I will not be drawing as much current with a gearmotor, on my 2WD with a DD and a gearmotor the difference in current for similar torque is substantial. So 30A is a peak value that won't be sustained much, though I will do some modelling before settling on the numbers.

I did review the video you made. You really worked hard to get that pack in. I hope to have less trouble based on what I've seen there. Making the pack a bit smaller and making it slightly flexible so it doesn't have to be perfectly straight should be helpful.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Mar 20 2018 3:23am

Now that I have a 3D printer it is interesting to look at designs that I could print that would support the batteries in the tube. I'm just trying some things to see if they'll fit at the moment, this is not a final design. I'm making these in PLA plastic right now, but I plan to make the final units in PETG which is water bottle plastic, very tough and somewhat flexible, and it handles high temperatures. It doesn't shrink like ABS so is good for hitting dimensions and staying flat.

I'm shooting for 14S4P of 18650 cells, probably 3.5AH GA types. This would yield 52V 14AH which is a lot of range for this efficient setup with BMC gearmotor and low air drag of the BikeE.

I'm leaning toward 14S4P because it will fit entirely in the middle section of the frame. 4P is also mechanically convenient and easy to parallel with a minimum of nickel. I have chargers for 14S. It will give me a little more speed on this bike, and that will be a good fit.

I can print 2S4P sections, so 7 of these will make the total pack. At the moment there are no slots for wiring, this is for cell and frame fit.
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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Mar 20 2018 8:51am

This is a challenging design due to the confined space. The width inside the frame tube is very tight, so the plastic needs to be thin, and possibly a little space added between the cells lengthwise to narrow the pack. The overall length of the pack is constrained by the crank in the front and the nut plates for rear forks. The rear forks (proper term?) are presently mounted to the frame tube by rivets, my plan is to drill them out and make a nut plate to slide in and support tee nuts in the proper places. There may be enough space there for the new PhaseRunner controller to be installed inside there, but that remains to be determined.

Each parallel group of 4 cells is close packed, they are allowed to touch as we don't need to insulate them from each other. The 14 groups are kept separated from each other and from the frame by a minimum of 0.6mm of plastic. I started with 1mm but that made the pack a bit long so I dropped it down to 0.6mm. The cells have insulation but that's quite thin and fragile so I don't plan to depend on that.

To make the pack slide easily in and out some flexibility will be incorporated between the blocks of cells. Not a great deal, but enough that alignment will not interfere with the fit into the frame. The conductors between blocks will be stranded copper so this flexibility will not put strain on the nickel strips.

We only need a peak pack current of about 25 amps, which is just over 6 amps per cell. A single nickel strip 7mm by 0.2mm can handle the current for one cell. We pick up this current in the middle of a strip paralleling two cells with a 16 gauge wire, which can easily handle the 12 amp combined current, while the strip carries only 6 amps on each side. The other 2 cells will have another strip and another 16 gauge wire. The wires can be pre-soldered to the strips before welding so soldering temperatures won't endanger the cells or separator plastic. Smaller copper conductors will be used for the balance conductors, probably a multicolored flat ribbon cable. The two 16 gauge conductors will combine for the main battery current, effectively about a 13 gauge conductor, as about 3 gauges are gained when two equal gauge wires are paralleled.

We will add slots for the conductors and more plastic to insulate the pack at the top and bottom as the design progresses.

The goal is to make the battery easy to construct and easy to slide into the BikeE frame channel.

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Re: BMC powered BikeE for Comfort and Range

Post by Alan B » Mar 20 2018 1:42pm

Made a couple more test prints. They seem to have a flaw in one area, not that it matters for these tests, but it would matter for production parts. On the left, in front, a section of the cell retaining cylinder is missing. This seems to be a problem with Cura, and it only seems to happen in the one area on this design. I suspect the speed is wrong on that extrusion, it is much weaker even where there is plastic, and the plastic is partly missing. Observing the printing, it appears to be moving slower on the left half of that cylinder, on the right half it is quite fast. I'm going to reprint but slow down the faster print speeds, I think that arc is miscategorized and printing at the wrong speed, so we're trying to cover for a slicer bug, but we'll see. It didn't help much. There still appears to be some very high speed moves that make no sense. There's a new version of Cura to update, I'll try that. The printer here is a Lulzbot Mini, so I'm using their version of Cura. It is a bit behind the regular Cura but it has a lot of pre-tuned filament settings that it comes with, and the firmware for the Lulzbot. Test stopped, it is printing the same.

On this iteration (in the foreground here), #4, the cells are a little more stretched out to narrow the pack while not exceeding the total length, and the cell retaining cylinders were increased slightly in thickness. The printing error was reduced but still there, and in exactly the same place.

If anyone has some Panasonic / Sanyo GA cells, I'd like some accurate measurements, especially diameter. We all know they're about 18mm, but what are they precisely?

So I downloaded another Slicer that I've been wanting to try. It's expensive, but it seems to be doing better. So far. Then it didn't. It looks bad and didn't hit dimensions at all. In reviewing, it appears that the settings shifted. I selected PLA, but after the print it says ABS. So the temperatures were way off, no wonder they were so hot. Should have stopped it right away.. So now we know what PLA looks like printed on the ABS settings... Not good.
Attachments
batteryHolderPrintingFlaw.PNG

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