Search found 13732 matches

by liveforphysics
Jun 03 2019 5:56am
Forum: Items for Sale - New
Topic: Nucular electronics - complete kit for ev! [beta]
Replies: 490
Views: 42737

Re: Nucular electronics - complete kit for ev! [beta]

I wouldn't say that surron motor is that good, it have quite low power factor. Since that it reaches battery voltage quickly and doesnt let you to use all avaible torque, it needs a lot of flux weakening to make it working good. Modern EVs are setup to rely on a ton of field weakening. It's a huge ...
by liveforphysics
Jun 03 2019 5:35am
Forum: Items for Sale - New
Topic: Nucular electronics - complete kit for ev! [beta]
Replies: 490
Views: 42737

Re: Nucular electronics - complete kit for ev! [beta]

That bike and rider are both awesome! That looks like an amazing control and performance upgrade controller. Great job! The Sur Ron motor for whatever reasons seems to love to drink all the power you can feed it, as long as you need them in big pulses. Fortunately, for many things, like technical ri...
by liveforphysics
Jun 02 2019 2:58pm
Forum: Technical Reference Area
Topic: Using EV Chargers
Replies: 58
Views: 1405

Re: Using EV Chargers

Tesla superchargers are like you described, but have a step where the vehicle VIN is requested, and the station uses a GSM modem to verify that VIN is approved to charge before it starts. You should share how to tap many J plugs to get useful charge power. I try to only stop at locations with 4 x jp...
by liveforphysics
Jun 02 2019 1:08pm
Forum: Battery Technology
Topic: Thread for new battery breakthrough PR releases
Replies: 1602
Views: 178919

Re: Thread for new battery breakthrough PR releases

Actually, that is a scam vehicle.

No configuration of 6 props passes the bird strike test requirements to fly human passengers.

Thats a movie prop made to lure VC cash.
by liveforphysics
May 31 2019 6:35pm
Forum: Battery Technology
Topic: Thread for new battery breakthrough PR releases
Replies: 1602
Views: 178919

Re: Thread for new battery breakthrough PR releases

Aluminium energy sounds cool because it is easy to recycle. I researched Alevo because the Innolith advertisement video is a bit suspicuous and oriented towards people who don't understand technology, the staff and labs don't appear in the innolith video, it's girls skipping in sunny green wheat fi...
by liveforphysics
May 31 2019 5:50pm
Forum: Battery Technology
Topic: New weldless battery system crowdfunfing project
Replies: 84
Views: 3520

Re: New weldless battery system crowdfunfing project

Polycarbonates + humidity + voltage stress = crazing (surface cracks), then crumbling.

Sometimes even good base plastic materials (polypropylene, Polyethylene can use a filler/dye that absorbs humidity and corrodes apart under voltage stress.

Test to validate whatever material you're going to use.
by liveforphysics
May 31 2019 1:14pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 3674
Views: 253348

Re: Sur-Ron - New Mid drive Bike

That's such a bad ass bike! Nice build, and great riding skills!
wuhaichao443 wrote:
May 31 2019 4:10am
some day
by liveforphysics
May 29 2019 11:31pm
Forum: Battery Technology
Topic: Inspiration to build Solderless battery
Replies: 41
Views: 1104

Re: Inspiration to build Solderless battery

Many good greases don't slump or run a bit clear beyond 120-150degC (250-300degF). The grease I use in the guns at the bike shop (Lucas Red 'n Tacky #2) has a drop point of 500F. I have no idea what its electrical conductivity is like. The grease at your shop likely works fine. The only issues you ...
by liveforphysics
May 29 2019 11:24pm
Forum: Battery Technology
Topic: Inspiration to build Solderless battery
Replies: 41
Views: 1104

Re: Inspiration to build Solderless battery

Many good greases don't slump or run a bit clear beyond 120-150degC (250-300degF).
by liveforphysics
May 29 2019 1:01am
Forum: Battery Technology
Topic: Inspiration to build Solderless battery
Replies: 41
Views: 1104

Re: Inspiration to build Solderless battery

The aluminum in that stack up will be fine when dry, but when moisture condenses in that gap between the surfaces, it will make a kind of 1 time use battery that has about ~0.6Vdc from the galvanic surface potentials. It will consume the interfaces through electrolysis corrosion over a period of we...
by liveforphysics
May 28 2019 10:49pm
Forum: Battery Technology
Topic: Inspiration to build Solderless battery
Replies: 41
Views: 1104

Re: Inspiration to build Solderless battery

The aluminum in that stack up will be fine when dry, but when moisture condenses in that gap between the surfaces, it will make a kind of 1 time use battery that has about ~0.6Vdc from the galvanic surface potentials. It will consume the interfaces through electrolysis corrosion over a period of wee...
by liveforphysics
May 21 2019 2:06pm
Forum: Battery Technology
Topic: What is the Best BMS for LG Chem batteries?
Replies: 9
Views: 442

Re: What is the Best BMS for LG Chem batteries?

In 2006, the parts you've got would be great. In the last 13years, a LOT has improved! It's kinda like if you started a computer build in 2006, and then 13 years pass, then you would need to re-consider the part choices and performance objectives in the project. Your build parts list seems really po...
by liveforphysics
May 17 2019 2:53pm
Forum: Battery Technology
Topic: What is the Best BMS for LG Chem batteries?
Replies: 9
Views: 442

Re: What is the Best BMS for LG Chem batteries?

Your build parts list seems really poorly selected with respect to cost/performance ratio. You can buy a whole running Nissan LEAF for the price of that motor controller choice. A wrecked Chevy Bolt would give you a 60kWh pack, inverter, harness, dash, and a 200hp motor. You can buy a whike salvaged...
by liveforphysics
May 16 2019 9:48am
Forum: General Discussion
Topic: Tesla switches to permanent magnet reluctance motors and sees range gains
Replies: 17
Views: 711

Re: Tesla switches to permanent magnet reluctance motors and sees range gains

Torque grows at the square of radius, linearly with length. Mass doesn't have to increase at the cube of volume if the shape is hollow inside (thin-gap, Joby, YASA). You can get any combination of electrical frequency you were getting with your gearing stage through increasing pole count and increas...
by liveforphysics
May 15 2019 7:15pm
Forum: General Discussion
Topic: Tesla switches to permanent magnet reluctance motors and sees range gains
Replies: 17
Views: 711

Re: Tesla switches to permanent magnet reluctance motors and sees range gains

Bigmoose! Always a pleasure to hear from you kind Sir! Toolman- It might be... The trick is in creating as short of flux linking path through the rotor, while maintaining the aggressive change in reluctance. If you make a rotor that when viewed from the side has a bunch of "U" shaped iron segments r...
by liveforphysics
May 13 2019 9:30pm
Forum: General Discussion
Topic: Tesla switches to permanent magnet reluctance motors and sees range gains
Replies: 17
Views: 711

Re: Tesla switches to permanent magnet reluctance motors and sees range gains

That's a very good TL;DR, thanks. Makes total sense for a car application. Aside from reducing magnetic drag massively, are the motors more efficient when power is being applied, or about the same as our trusty permanent magnet motors? PM motors at full load can achieve ~97% when everything is done...
by liveforphysics
May 13 2019 8:23pm
Forum: General Discussion
Topic: Tesla switches to permanent magnet reluctance motors and sees range gains
Replies: 17
Views: 711

Re: Tesla switches to permanent magnet reluctance motors and sees range gains

That's quite the post! How about the cliff notes version? These motors seem awfully similar to BLDC.. what's the difference between the two? Our ebike motors use the PMs for making the motors whole torque. The Tesla motor just has a tiny amount of weak PMs, so it can cruise down the highway at ligh...
by liveforphysics
May 12 2019 11:44pm
Forum: E-Vehicles General Discussion
Topic: High voltage wire, crimp connectors, and not dying
Replies: 9
Views: 403

Re: High voltage wire, crimp connectors, and not dying

40-50V is where fatality becomes much more likely. Thats just not true for skin contact shocks, only if you stick the wire through your skin. If you're shocked with the current path across the chest at 300-400Vdc, you have a strong dice roll for it being your last earthly sensation. Best case, the ...
by liveforphysics
May 11 2019 8:29pm
Forum: Battery Technology
Topic: Solderless weldless 36V and 74V batteries could do over 200A
Replies: 50
Views: 1722

Re: Solderless weldless 36V battery could do 200A

flippy wrote:
May 10 2019 1:56am
how do you ensure a solid heat resistant connecton with the cell terminals?
Thats the challenge you solve when you do a solderless pack. As many ways to solve it as your creativity supports. It seems like an easier challenge IMHO than solving thermal damage to cells.
by liveforphysics
May 11 2019 3:51pm
Forum: E-Bike Non-hub Motor Drives
Topic: Strange Middrive Efficiency
Replies: 8
Views: 463

Re: Strange Middrive Efficiency

Less motor core loss and gearing drag losses.

It's a misconception motors want speed for efficiency. More speed = more losses.

Only if youe copper losses are higher than your core losses do you want more motor speed to increase efficiency. At a steady cruising pace, this almost never happens.
by liveforphysics
May 10 2019 3:26pm
Forum: Battery Technology
Topic: end cells always fail first, why?
Replies: 15
Views: 649

Re: end cells always fail first, why?

That's a fantastic question, and you do see end cells die more commonly than any other cells in most pack designs. This is because of a current path that's not sharing current uniformly at the end terminations, and hence not heating uniformly at the ends. If you don't have temperature uniformity and...
by liveforphysics
May 09 2019 8:15pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 3674
Views: 253348

Re: Sur-Ron - New Mid drive Bike

30Q is for hotrodders.

I didn't run through the breaker.
by liveforphysics
May 09 2019 12:30pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 3674
Views: 253348

Re: Sur-Ron - New Mid drive Bike

Since your new pack has ~half the sag, you should be able to draw double the power from it (for same cell stress/heating).

Time for a controller upgrade!!! :-) That motor loves to eat big power!!!