Search found 112 matches

by Pedrodemio
Nov 30 2020 8:24am
Forum: E-Bike Non-hub Motor Drives
Topic: My RC Mid Drive with Single Stage Reduction
Replies: 369
Views: 53503

Re: My RC Mid Drive with Single Stage Reduction

It doesn't look that bad being huge, I may paint it black to mask a bit Screwed up a bit on the motor mount design, it cover the rear shifter cable mount, a bit of dremeling may solve that, in the future I probably will do a new mount in front of the pedal, I avoided that because the downtube geomet...
by Pedrodemio
Nov 26 2020 5:39pm
Forum: E-Bike Non-hub Motor Drives
Topic: My RC Mid Drive with Single Stage Reduction
Replies: 369
Views: 53503

Re: My RC Mid Drive with Single Stage Reduction

Nice to hear that Yeah, the VESC firmware has a problem with tracking at low duty cycles, on low power builds or/and ones that use a non optimal gearing it gets really apparent I plan to play with that, instead of dropping the Kv, lowering the voltage may also work since you would increase the duty ...
by Pedrodemio
Nov 25 2020 4:27pm
Forum: E-Bike Non-hub Motor Drives
Topic: My RC Mid Drive with Single Stage Reduction
Replies: 369
Views: 53503

Re: My RC Mid Drive with Single Stage Reduction

Since you aren't using a crank freewheel can you use the slack side of the motor reduction for torque measurement or am I not understanding correctly? This is actually a good idea, I will think about for a while Probably the slack side would have to have a pre load, if we could measure hpw that pre...
by Pedrodemio
Nov 25 2020 2:42pm
Forum: E-Bike Non-hub Motor Drives
Topic: My RC Mid Drive with Single Stage Reduction
Replies: 369
Views: 53503

Re: My RC Mid Drive with Single Stage Reduction

Nice sprocket collection! Just curious, where did you source them? What motor are you using? Thanks, they are custom laser cut, there is a shop in my city that does this kind off service ridiculously cheap, if I were to convert to dollar, all these parts, minus the chain, would be $26 Shiny ones 30...
by Pedrodemio
Nov 25 2020 2:03pm
Forum: E-Bike Non-hub Motor Drives
Topic: My RC Mid Drive with Single Stage Reduction
Replies: 369
Views: 53503

Re: My RC Mid Drive with Single Stage Reduction

Inspired from all of you guys, I've started working on my own

The previous version was a friction drive, but it didn't work that well and for some reason I blew a lot of tires with it
IMG_0649 (Editado).JPG
IMG_0649 (Editado).JPG (396.63 KiB) Viewed 505 times
by Pedrodemio
Nov 24 2020 8:45am
Forum: E-Bike Non-hub Motor Drives
Topic: Custom frame for the Cyclone Coaxial motor
Replies: 173
Views: 21520

Re: Custom frame for the Cyclone Coaxial motor

I've been silently following this build for a while

If there is a dream bike for me, is someday building a similar frame as that, can't wait to see the results

Well done Chambers
by Pedrodemio
Nov 13 2020 2:55pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 508
Views: 56552

Re: Li-ion cells cycle ageing

Pajda wrote:
Nov 13 2020 2:27pm

Did you check shipping cost? This item is heavy and so the shipping cost is high. The price 260 USD which I posted is a good price with shipping included.
Didn't, but it's $170, no deal, but shipping of anything is ridiculously expensive to get it here, I'm not on the US
by Pedrodemio
Nov 13 2020 1:24pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 508
Views: 56552

Re: Li-ion cells cycle ageing

Good question, yes there is a solution from ZKE model EBC-A40L with internal 35A charge and 40A discharge current, but it is way more expensive, about 260 USD is best price. In this price range you can find some better modeler battery charger (Cellpro Powerlab 6) which can also do cycle test with l...
by Pedrodemio
Nov 13 2020 12:13pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 508
Views: 56552

Re: Li-ion cells cycle ageing

I've adjusted the post. Sorry for bothering you, but the cut-off current is in mA, not mAh. :wink: But more importantly I would like to present your work as excellent example of how easily with more than satisfactorily accuracy you can verify your favourite cell parameters. I think that 120-150 USD...
by Pedrodemio
Nov 01 2020 9:15pm
Forum: Motor Technology
Topic: Motor Analysis Sotfware
Replies: 2
Views: 506

Re: Motor Analysis Sotfware

I'm using MotorAnalysis, free and powerful, more intuitive than FEMM

https://motoranalysis.com/
by Pedrodemio
Sep 23 2020 9:01pm
Forum: Electric Watercraft
Topic: Shamrock, 25 foot sailboat electric conversion with an ebike hub motor
Replies: 40
Views: 3412

Re: Shamrock, 25 foot sailboat electric conversion with an ebike hub motor

Awesome project Justin, good luck on it

If I heard it right do you plan to also put some solar panels?
by Pedrodemio
Aug 23 2020 9:58pm
Forum: Battery Technology
Topic: Can charging my bike be made easier?
Replies: 12
Views: 404

Re: Can charging my bike be made easier?

Good point

The thing that I would do is never connect the chargers in parallel first because of small differences in voltage

Connect first one to the pack and then the second

I want to try that for a long time, if I do will post here
by Pedrodemio
Aug 23 2020 9:47pm
Forum: Battery Technology
Topic: Can charging my bike be made easier?
Replies: 12
Views: 404

Re: Can charging my bike be made easier?

You could charge all five batts left parallelled with ONE charger. That would be no problem. charge current to each small batteries would be 1/5 th the output of the charger. BUT, my concern is if you want to use BOTH chargers at the same time, then you PROBABLY need to modify the second charger an...
by Pedrodemio
Aug 23 2020 9:18pm
Forum: Battery Technology
Topic: Can charging my bike be made easier?
Replies: 12
Views: 404

Re: Can charging my bike be made easier?

I would parallel all charge plugs and plug both chargers in parallel there
by Pedrodemio
Jul 28 2020 1:47pm
Forum: Motor Technology
Topic: Virtual Motor Dyno - Efficiency maps for any motor
Replies: 0
Views: 340

Virtual Motor Dyno - Efficiency maps for any motor

Hi everyone This is a project that I've been wanting to do for a long time, a virtual motor dyno that from just a few measurements enables us to plot efficiency map, total losses, copper losses, core losses and output power I made this intended for smaller motors for electric skateboards, but proble...
by Pedrodemio
May 15 2020 8:17am
Forum: E-Bike Non-hub Motor Drives
Topic: VESC 6, astroflight 3215, loosing sync with freewheel
Replies: 5
Views: 344

Re: VESC 6, astroflight 3215, loosing sync with freewheel

Glad it's solved, the duty cycle mode on the VESC behaves completely different than what most people are used to on other ESCs
by Pedrodemio
May 11 2020 1:46pm
Forum: E-Bike Non-hub Motor Drives
Topic: VESC 6, astroflight 3215, loosing sync with freewheel
Replies: 5
Views: 344

Re: VESC 6, astroflight 3215, loosing sync with freewheel

You shouldn't use duty cycle mode on VESC since it doesn't have free wheel, when you release the throttle it starts to brake since the duty cycle you want is now 0%

Try using current no reverse with brake
by Pedrodemio
Mar 10 2020 11:59am
Forum: Battery Technology
Topic: Fast Charging - What is the secret?
Replies: 36
Views: 2454

Re: Fast Charging - What is the secret?

And the no temperature rise I disagree, if a hot battery has faster reactions, and the consequence is that it allows faster charging, maybe it's good that when charging, even at lower rates, making it hot improves cycle and calendar life Sorry if I wasn't clear. Yes heating the battery reduces the ...
by Pedrodemio
Mar 10 2020 9:18am
Forum: Battery Technology
Topic: Fast Charging - What is the secret?
Replies: 36
Views: 2454

Re: Fast Charging - What is the secret?

Agree with everything, it's a matter of finding a optimum compromise And the no temperature rise I disagree, if a hot battery has faster reactions, and the consequence is that it allows faster charging, maybe it's good that when charging, even at lower rates, making it hot improves cycle and calenda...
by Pedrodemio
Mar 09 2020 10:13pm
Forum: Battery Technology
Topic: Fast Charging - What is the secret?
Replies: 36
Views: 2454

Re: Fast Charging - What is the secret?

This would be figured out with the testing, from what I've been reading it depends, each cell is different and you absolutely can't use findings from one cell in another It's not just temperature, but the big problem is lithium plating, I'm talking now without any good understanding of what is happe...
by Pedrodemio
Mar 09 2020 5:36pm
Forum: Battery Technology
Topic: Fast Charging - What is the secret?
Replies: 36
Views: 2454

Re: Fast Charging - What is the secret?

fast charging at the level that tesla does is not relevant for home gamers. the temperature managment system is impossible to recreate and as other car companies alreayd have proven: impossible to equal. if -as a home gamer- you need fast charging at the level that tesla does you need to reconsider...
by Pedrodemio
Mar 05 2020 1:47pm
Forum: Battery Technology
Topic: Tesla Battery Day
Replies: 3
Views: 482

Re: Tesla Battery Day

This guy has been doing an awesome research on everything that could be incorporated into the new cells

https://www.youtube.com/watch?v=T5Y0GAVWnE4

https://www.youtube.com/watch?v=Vt1XO5_xHss
by Pedrodemio
Feb 18 2020 5:49pm
Forum: Battery Technology
Topic: Fast Charging - What is the secret?
Replies: 36
Views: 2454

Re: Fast Charging - What is the secret?

Getting the cells pre-heated even to borderline damaging temps does reduce the damage (lost cycles) inflicted by high rate charging. I think it would be very hard to push these limits the way Tesla engineers can. But there are use cases where it's worth trying, fast charging being essential to the ...
by Pedrodemio
Feb 16 2020 9:52pm
Forum: Battery Technology
Topic: Fast Charging - What is the secret?
Replies: 36
Views: 2454

Fast Charging - What is the secret?

As an enthusiast for all things electric, I've always wondered what allows fast charging Lets take the Model 3 as the prime example at the current date, capable of a 250 kW peak charging rate, with a 96s46p, taking into account that that peak only happens at low state of charge, we are taking about ...
by Pedrodemio
Feb 06 2020 10:48pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 508
Views: 56552

Re: Li-ion cells cycle ageing

docware, thanks a lot for undertaking this endeavor, doing a whole lot of cell cycling tests is something I always wanted to do, but unfortunately I have no conditions at the moment or in the foreseeable future One suggestion for the future of the tests I’ve mainly build electrical skateboards, and ...