Search found 2909 matches

by madin88
Feb 20 2020 3:46am
Forum: Motor Technology
Topic: Neumotor 8057/75 middrive project, belt drive, adding halls, 10kW+
Replies: 144
Views: 26855

Re: Neumotor 8057/75 middrive project, belt drive, adding halls, 10kW+

This addition of hall sensors looks deceptively simple. I'm looking to add halls to a Neumotors 8038/100. Would the same dimensions work? Is the design optimal? Any chance I could use your CAD? The motors seem to have identical shaft and mounting dimensions so it should work. If you give me your em...
by madin88
Feb 13 2020 4:55am
Forum: E-Scooter and Motorcycle Photos & Videos
Topic: Suzuki GSX-R e899 K2
Replies: 424
Views: 65165

Re: Suzuki GSX-R e899 K2

Hi Frank, Of course, I want to install the motor as close as possible to the OEM sprocket position but the radius of the motor will determine the position at the end. If the chainline is above the swingarm pivot it will compress the rear suspension during acceleration (you would loose grip, seat go...
by madin88
Feb 12 2020 3:22am
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 955
Views: 73268

Re: APL's DIY axial-flux motor

APL wrote:
Feb 11 2020 11:16pm
As stated before, N52's aren't the best magnets to be working for this, and are probably lending to the problem.
Then 80°C
With those you get automatic field weakening when the motor heats up
More heat = more speed :mrgreen:
by madin88
Feb 11 2020 3:29pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 955
Views: 73268

Re: APL's DIY axial-flux motor

Get one thing figured out, and another pops up. Fechter was right about grinding magnets,.. it does diminish their power. But I'm not sure whats doing the damage,.. when I took the temperature immediately after grinding, it was never above 70 degrees. So maybe the vibration, along with momentary he...
by madin88
Feb 10 2020 6:33am
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 955
Views: 73268

Re: APL's DIY axial-flux motor

APL it is nice to see you are taking the effort with segmentation, but braking magnets into pieces and sand them to shape sounds like troubles with debries and the dust is known to be unhealthful. I understand that you wanna do as much DIY as possible, but i have the opinion that one should not over...
by madin88
Feb 10 2020 5:54am
Forum: Battery Technology
Topic: 100% discharge rate capacity
Replies: 109
Views: 2374

Re: 100% discharge rate capacity

everyone says im wrong and I most certainly am but why hasn't anyone that's saying that im wrong posted a link to the results of a 30q tested 250 times at a 1c constant discharge? Nobody but you has to proove anything here. It's your statments which stand against whats known so far about cylce life...
by madin88
Feb 07 2020 7:51am
Forum: Battery Technology
Topic: 100% discharge rate capacity
Replies: 109
Views: 2374

Re: 100% discharge rate capacity

I want to know why 3 amps kills a 30q let me try to explain this way, when a 30q can deliver 100% of its capacity its working the way it was designed and the further from 100% it operates the quicker it degrades and resistance goes up. Samsung 30q discharge 0.6amps is 100% 5amps is 97% 10amps is 10...
by madin88
Feb 07 2020 5:18am
Forum: Motor Technology
Topic: QS 3000w midmotor
Replies: 494
Views: 54974

Re: QS 3000w midmotor

it is exceed belt torque at 500A phase, there is no service factor left, at 500A it should make over 70Nm on shaft and calculated belt width is 60mm, 3 times more than your stock pulley Those rubber belts are the wrong choice IMO for this purpose. It needs something better, like Gates PolyChain or ...
by madin88
Feb 07 2020 5:10am
Forum: Items for Sale - New
Topic: QS MOTOR,0.5-14kW Electric Hub Motor Manufacture China
Replies: 1301
Views: 249754

Re: QS MOTOR,0.5-14kW Electric Hub Motor Manufacture China

QS Motor 1200W 212 35H V1.12 electric bike spoke hub Motor/bicycle spoke motor/Low power electric bike For QS motor 1200w 212 35H V1.12 electric motor, it’s new design and especially upgrades for low power electric bike. It could be 48V, available in a variety of sizes, such as 24inch, 26inch E-Bik...
by madin88
Feb 07 2020 4:32am
Forum: Battery Technology
Topic: Over-discharging lithium ion cells and the effects
Replies: 13
Views: 549

Re: Over-discharging lithium ion cells and the effects

0% SOC means 0V I can't imagine even the most ivory tower disconnected from reality academic setting that hypothesis with those chemistries. You have right. 0% on this particular test means 3.4V https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4957210/#__sec1title Below 3.4V, decomposition of SEI (soli...
by madin88
Feb 07 2020 3:49am
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 312
Views: 28329

Re: Li-ion cells cycle ageing

The principle of this issue was already formally described in this topic. So yes HP cells have significantly worse cycle life than most HE cells under low loads up to ca 1-2C continuous discharge. Generally(Although I do not like generalizations) HP cells cycle life is almost independent of the loa...
by madin88
Feb 06 2020 1:19pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 312
Views: 28329

Re: Li-ion cells cycle ageing

I was referring to high current cells like VTC6, HG2, 30Q where 5-10A discharge and 2A charge would be within specs of course.
by madin88
Feb 06 2020 12:51pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 312
Views: 28329

Re: Li-ion cells cycle ageing

OK thanks.
docware wrote:
Feb 06 2020 12:19pm
Currently we are running tests at these particular conditions.
Which cell at which conditions exactly?
by madin88
Feb 06 2020 12:37pm
Forum: Battery Technology
Topic: 100% discharge rate capacity
Replies: 109
Views: 2374

Re: 100% discharge rate capacity

im talking about when a cell can deliver 100% of its capacity, big difference. you can cycle your cells at 4.1v to 3.4v but operate the cell the way its designed to operate. 30q is 10amps. if its operating at 100% the chemical reaction is behaving like a clean burn, not creating deposits inside the...
by madin88
Feb 06 2020 12:19pm
Forum: Battery Technology
Topic: Over-discharging lithium ion cells and the effects
Replies: 13
Views: 549

Re: Over-discharging lithium ion cells and the effects

More or less. So if manufacturer specifies brackets of 2.8V and 4.2V and within that range states a capacity of 2000mah at 1C, -12% would render voltage of 2.46V which, regarding article would render little to no risk of copper electrods being dissolved in electrolite thus no damage to cell? Accord...
by madin88
Feb 06 2020 11:41am
Forum: Battery Technology
Topic: 100% discharge rate capacity
Replies: 109
Views: 2374

Re: 100% discharge rate capacity

hey john stresses can be many things, a cell operating at 100% shouldn't be too stressed if that's where it retains its capacity a cell operating at 90% seems to get a little stressed out and starts to lose capacity am I wrong by thinking if a cell is operating at its 100% discharge rate capacity t...
by madin88
Feb 06 2020 11:22am
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 312
Views: 28329

Re: Li-ion cells cycle ageing

Thats all very interesting thanks for sharing docware :thumb: I have a small question, as LG seems to have so much better cycle life, couldn't it be because of the higher LVC? LG was 4,1 - 3,4V, and all other down to 3,3V. If find it quite surprising that if you use high current cells at very low di...
by madin88
Feb 04 2020 7:41am
Forum: E-Bike General Discussion
Topic: E-S LMX 64 Bike Owners
Replies: 384
Views: 41640

Re: E-S LMX 64 Bike Owners

https://youtu.be/PcBaZ9sO9A4
:)
Silixcon once was part of Pearcontrol or so.
by madin88
Feb 03 2020 1:49pm
Forum: E-Bike General Discussion
Topic: New Gallium(GaN) chargers -any tangible benefit to ebike battery charging?
Replies: 3
Views: 219

Re: New Gallium(GaN) chargers -any tangible benefit to ebike battery charging?

nickceouk wrote:
Feb 03 2020 12:02pm
There are other things like reference designs for GaN rectifier but 54.6v are not to be found :roll:
Eltek Flatpack SHE have GaN transistors and achieve almost 98%.

https://www.eltek.com/globalassets/medi ... ochure.pdf
by madin88
Feb 02 2020 2:30pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 955
Views: 73268

Re: APL's DIY axial-flux motor

But theres also 'Coil Span', which is all the coil widths added together,.. minus one. Engineers have determined that you can diminish harmonics by adjusting coil span. A coil span of 144 deg. will neutralize 5th order harmonics, and a coil span of 154.3 deg. will take care of 7th order harmonics. ...
by madin88
Feb 02 2020 1:40pm
Forum: Motor Technology
Topic: QS 3000w midmotor
Replies: 494
Views: 54974

Re: QS 3000w midmotor

PID only improves how your speed is reached, it’s not the basic motor control? so can be annoying but not related to motor performance? Those parameters have influence on current regulation and some users indeed did report about gains in acceleration. Also when i was playing with them i was able to...
by madin88
Jan 26 2020 3:33pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 312
Views: 28329

Re: Li-ion cells cycle ageing

To get a true representation of battery ageing or wearout, the tests must be run with complete batteries ... just as they would be in the planned application. Similarly, extrapolating the performance of the whole population of batteries from a sample of one [cell] can also give unreliable results a...
by madin88
Jan 26 2020 8:30am
Forum: Motor Technology
Topic: Revolt RV-series motor review and comparisons
Replies: 286
Views: 32438

Re: Revolt RV-series motor review and comparisons

...Maybe I should stop spreading the myth that peak efficiency is when copper and iron losses are equal... Why are you calling it a myth? As long as you add "for a given voltage" it's true AFAIC and I proved it to myself with a quick bit of trial and error using the spreadsheet. Thanks for pointing...
by madin88
Jan 23 2020 4:43am
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 312
Views: 28329

Re: Li-ion cells cycle ageing

@ eMark You need to compare either rest voltage with rest voltage, or load voltage with load voltage to get an apples to apples comparison. Also during charge the battery will be under "load", therefore the voltage will be higher as it would be at rest. When looking at red (1A) curve from following ...
by madin88
Jan 23 2020 4:22am
Forum: Motor Technology
Topic: Revolt RV-series motor review and comparisons
Replies: 286
Views: 32438

Re: Revolt RV-160-SH update

82v x 10 amps = 820 watts (phase amps) 82v x 6 amps = 492 watts (battery amps) I listed both in case people cared. It's not an error, it's being thorough. If you want to convert 82V DC into 3-phase AC which is what the controller is doing, it cannot be 82V RMS on the output even at 100% PWM or WOT ...