Search found 102 matches

by Pedrodemio
Sep 23 2020 9:01pm
Forum: Electric Watercraft
Topic: Shamrock, 25 foot sailboat electric conversion with an ebike hub motor
Replies: 30
Views: 1450

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: 335

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: 335

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: 335

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: 303

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: 291

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: 291

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: 2305

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: 2305

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: 2305

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: 2305

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: 450

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: 2305

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: 2305

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: 472
Views: 52474

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 ...
by Pedrodemio
Jan 19 2020 12:18am
Forum: Battery Technology
Topic: Project: Replace 18650 cells in laptop battery (w/pictures)
Replies: 18
Views: 2735

Re: Project: Replace 18650 cells in laptop battery (w/pictures)

A long time I did mine, but this should be helpful to others In short, use the same capacity cells I used NCR18650B, 3400 mAh vs the 2200 mAh original, at the first charge and discharge it worked, the BMS was calibrating. It lasted a long time compared to the old battery, nearly doubled As soon the ...
by Pedrodemio
Jan 18 2020 9:38pm
Forum: E-Bike Non-hub Motor Drives
Topic: Kepler Friction drive comes of age.
Replies: 403
Views: 80746

Re: Kepler Friction drive comes of age.

Thanks for the tips Did a few more tests using a short lead with the switch really close and all problems solved, so now I have to find a way to remove the noise from the long cable, at least its not another VESC down the drain If you are interested I documented the build here, still a work in progr...
by Pedrodemio
Jan 18 2020 4:49pm
Forum: E-Bike Non-hub Motor Drives
Topic: Kepler Friction drive comes of age.
Replies: 403
Views: 80746

Re: Kepler Friction drive comes of age.

Hi Kepler I've been a fan of your drive for a long time, and made a fixed version in my bike that I was road testing with just a simple ADC button connected to the VESC for a long time Now that everything is tested I've implemented a more complex single button control using an AtTiny but the same pr...
by Pedrodemio
Jan 03 2020 3:31pm
Forum: E-Bike Technical
Topic: How much beating can a hub take?
Replies: 7
Views: 837

Re: How much beating can a hub take?

In theory, the bearings on the axle should take the loading between hub cover and axle, but some people have discussed breakage of plastic gears inside geared hubs, or of teh clutch itself. I'm not certain that's directly from the impact, but might rather be from the motor / wheel spinning really f...
by Pedrodemio
Dec 30 2019 11:36pm
Forum: E-Bike Technical
Topic: How much beating can a hub take?
Replies: 7
Views: 837

How much beating can a hub take?

Hey guys, for a long time I've been thinking if switching my bike to a low power hub motor like the G310, I don't need much power, currently I run a friction drive with RC motors, but due to a bunch of factors the low speed torque is bad What worries me is if they can take the way I ride, I like to ...
by Pedrodemio
Feb 12 2018 12:53pm
Forum: Battery Technology
Topic: Samsung 30Q hard voltage drop under load?
Replies: 23
Views: 2042

Re: Samsung 30Q hard voltage drop under load?

If possible post a picture or a schematic of how you wired the back, but if only 3 nickel strips are used for the serial connections there is your problem, and if it is, I recommend you stop using the pack until fixed, the least that can happen is these 3 nickel strips melt, the worst they melt and ...
by Pedrodemio
Oct 01 2017 9:51pm
Forum: Items for Sale - New
Topic: 6pence Resistance Spot Welder
Replies: 190
Views: 38059

Re: 6pence Resistance Spot Welder

Everything works perfectly now. Switched to copper and two batteries in parallel, using 1.5 and 6ms I can weld 0.15mm nickel with no problem

Image
by Pedrodemio
Sep 26 2017 2:11pm
Forum: Items for Sale - New
Topic: 6pence Resistance Spot Welder
Replies: 190
Views: 38059

Re: 6pence Resistance Spot Welder

Just finished mine I have two problems, but both are easily mended First, apparently my battery isn't up to the job, it's a 3S 5000mah 35-70C Turnigy nanotech, i preferred to teste with it since car batteries are not cheap around here. First i need to charge it since it was sitting for more than 2 y...
by Pedrodemio
Sep 05 2017 12:52pm
Forum: Battery Technology
Topic: Project: Replace 18650 cells in laptop battery (w/pictures)
Replies: 18
Views: 2735

Re: Project: Replace 18650 cells in laptop battery (w/pictur

Thanks, I will try them, will report back soon
by Pedrodemio
Sep 05 2017 7:38am
Forum: Battery Technology
Topic: Project: Replace 18650 cells in laptop battery (w/pictures)
Replies: 18
Views: 2735

Re: Project: Replace 18650 cells in laptop battery (w/pictur

Nice work Could you post your laptop ad battery models? I've already purchased the cells, just have to finish my spot welder to replace them, but I've read somewhere that some BMS's can't be disconnected and reconnected or they enter a protection mode that bricks it, if we have the same model it wou...