Search found 90 matches

by Pedrodemio
Feb 18 2020 5:49pm
Forum: Battery Technology
Topic: Fast Charging - What is the secret?
Replies: 23
Views: 590

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: 23
Views: 590

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: 312
Views: 28781

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: 13
Views: 1683

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: 395
Views: 70844

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: 395
Views: 70844

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: 708

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: 708

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: 1890

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: 33072

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: 33072

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: 13
Views: 1683

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: 13
Views: 1683

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...
by Pedrodemio
Feb 10 2017 12:22pm
Forum: Battery Technology
Topic: JP spot-welder, FET-switched, timed adj. pulse
Replies: 612
Views: 68991

Re: DIY spot-welder, FET-switched, processor-timed adj. puls

Thanks fechter, i will try it and see what happens
by Pedrodemio
Feb 10 2017 7:01am
Forum: Battery Technology
Topic: JP spot-welder, FET-switched, timed adj. pulse
Replies: 612
Views: 68991

Re: DIY spot-welder, FET-switched, processor-timed adj. puls

Hello guys, i'm about to start building my spot welder Anyone tried using lipos to weld 0.15mm nickel? i have two Nanotech's 5000mah 35-70C laying around that in theory should be able to reach 900A considering the internal resistance, a car battery is expensive around here and i don't want to risk d...
by Pedrodemio
Feb 08 2017 8:32am
Forum: Items for Sale - New
Topic: CHEAP NEW ORIGINAL 18650 BATTERY CELLS AND PACKS
Replies: 793
Views: 213431

Re: NEW CELLS 18650 SAMSUNG/SANYO/PANASONIC/LG 2900-3500mAh

Hardergamer wrote:Really 60%!? WOW Would it not be cheaper to get them from Japan.
It's luck around here, generally things that come from asia haver a higher chance of being taxed
by Pedrodemio
Feb 02 2017 12:19pm
Forum: Items for Sale - New
Topic: CHEAP NEW ORIGINAL 18650 BATTERY CELLS AND PACKS
Replies: 793
Views: 213431

Re: NEW CELLS 18650 SAMSUNG/SANYO/PANASONIC/LG 2900-3500mAh

Dicast wrote:Hi

Do you ship to Brazil?
If yes.how much would cost?

You have to send a PM for him to answer, i'm from Brazil too and the shipping for 30 cells was cheap, unfortunately it's almost certain that you will have to pay the 60% import fee + the abusive fixed R$12,00 fee, at least that was my case
by Pedrodemio
Dec 09 2016 4:13pm
Forum: Motor Technology
Topic: Motor Design Software
Replies: 8
Views: 1342

Re: Motor Design Software

have you seen this? https://www.emetor.com/ MotorCAD is the industry standard for thermal analysis of motors but they now have an electromagnetic module that works in conjunction. All the commercial software is extrmely expensive. I would rough out the design in Emetor before choosing anything more...
by Pedrodemio
Dec 09 2016 8:38am
Forum: Motor Technology
Topic: Motor Design Software
Replies: 8
Views: 1342

Re: Motor Design Software

That would be a way, but my mais objective is to learn something new, if in the end i can make a good motor that's great, but if the motor its not so good but i know what to improve or where i've screwed, that's even better I've been following all the hubs on eboard section, from what i've seen from...
by Pedrodemio
Dec 08 2016 7:01pm
Forum: Motor Technology
Topic: Motor Design Software
Replies: 8
Views: 1342

Motor Design Software

Hello guys, I will shortly start a work in a research in my university to develop and manufacture a hub motor for electric skateboards, my goal is to optimize it as much as possible, since the application requires it or i will step on problems like overheating and huge consumption. So to the point, ...
by Pedrodemio
Aug 04 2016 12:47pm
Forum: Stand-up E-scooters and E-skateboards
Topic: OpenSource Remote for VESC ArduBoardControl
Replies: 263
Views: 36192

Re: OpenSource Remote for VESC ArduBoardControl

This seems to be the same type i got when reading the serial while it is sending data to VESC And speaking on serial, finally everything works, rode my board a lot this last days, but today when i was implementing the battery capacity led's i realized i'm no getting any data back from VESC, anyone h...
by Pedrodemio
Jul 19 2016 12:59pm
Forum: Stand-up E-scooters and E-skateboards
Topic: OpenSource Remote for VESC ArduBoardControl
Replies: 263
Views: 36192

Re: OpenSource Remote for VESC ArduBoardControl

[*]Funny thing, when everything seems to be going, something have to screw up Was on the verge of finishing the board again, testing on 10S for the first time, BLDC working, FOC working, and then on one of the accelerations on the bench the motor just made a high pitched sound and after rebooting it...
by Pedrodemio
Jul 11 2016 2:03pm
Forum: Stand-up E-scooters and E-skateboards
Topic: OpenSource Remote for VESC ArduBoardControl
Replies: 263
Views: 36192

Re: OpenSource Remote for VESC ArduBoardControl

I'm using it with a few modifications for leds(was using, my board is down for a few months so far)

Try using the abs tachometer, any situation that makes the wheels go backwards? this would add negative distance if the abs is not used
by Pedrodemio
Jul 04 2016 9:15pm
Forum: Stand-up E-scooters and E-skateboards
Topic: OpenSource Remote for VESC ArduBoardControl
Replies: 263
Views: 36192

Re: OpenSource Remote for VESC ArduBoardControl

I've checked here, the pulse number that i said, i'ts the motor poles*3, for a 14 pole motor that gives 42 pulses per rotation. As i understand, that's the number of sequencial phase activation to complete a full rotation. For the ERPM, i got RPM = ERPM*2/ Motor_Poles See if this works #define DIA_W...
by Pedrodemio
Jul 02 2016 9:26pm
Forum: Stand-up E-scooters and E-skateboards
Topic: OpenSource Remote for VESC ArduBoardControl
Replies: 263
Views: 36192

Re: OpenSource Remote for VESC ArduBoardControl

rpm is the instantaneous rotational speed of the motor, tachometer is the number of pulses, or absolute number in case of abs_tachometer, the VESC has counted since powered on, in my tests i got 40 pulses per full rotation in a 14 pole motor, for speed you should use only the rpm and apply the corre...