Search found 1987 matches

by Voltron
Oct 26 2019 1:16pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 53
Views: 4433

Re: 4x less coasting resistance

Passing the magnets induces an electric current, that's where the heat is coming from. If it was just a stationary magnetic pull, it wouldn't be heating, it's the moving a conductor thru a magnetic field Faraday thing.
by Voltron
Oct 24 2019 5:18pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 53
Views: 4433

Re: 4x less coasting resistance

Hummina Shadeeba wrote:
Oct 24 2019 3:32pm
Low cogging yet bad on knees I don’t understand.


If it’s drag, a magnetic drag, where is the energy going exactly? Call it whatever u want but where is the energy going
The energy is going into heat... As the iron rotates thru the alternating magnet fields it's slowly getting hotter.
by Voltron
Oct 24 2019 12:59pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 53
Views: 4433

Re: 4x less coasting resistance

The cogging feel of spinning a motor shaft by hand is deceptive. You feel the resistance as it builds to hopping towards the next magnet, but it's easy to miss the force it would take to slowly ease it to the next neutral point, instead of just letting it jump there. They balance each other out. On ...
by Voltron
Oct 22 2019 12:17pm
Forum: E-Bike Non-hub Motor Drives
Topic: drone pancake motor low reduction mid drive with regen
Replies: 16
Views: 4099

Re: drone pancake motor low reduction mid drive with regen

No, it was a little different, but same basic idea... Or a different iteration of it from the same company.
by Voltron
Oct 20 2019 5:37pm
Forum: E-Bike Technical
Topic: Confusing battery info
Replies: 9
Views: 825

Re: Confusing battery info

Yes... The whole 36v, 48v, and 52v thing is the mid point voltage of a pack, which is why people sometimes call them by the series number... A normalish lithium cell is 3.6v halfway charged, and 4.2v fully charged. So a so called 36v battery is 10 groups in series, so 42v fully charged. 48v is 13s, ...
by Voltron
Oct 18 2019 1:08pm
Forum: E-Bike Non-hub Motor Drives
Topic: drone pancake motor low reduction mid drive with regen
Replies: 16
Views: 4099

Re: drone pancake motor low reduction mid drive with regen

There's hardly anything that's lighter and more efficient than a single stage reduction with belt or chain. Unless you have special space configuration issues, or need to slave multiple motors together, it's not worth the weight and efficiency hits. Most non crank drive, non friction rc drives basic...
by Voltron
Oct 16 2019 7:15pm
Forum: General Discussion
Topic: Crash Thread - lucky
Replies: 38
Views: 5095

Re: Crash Thread - lucky

Damn DAND! That sucks!
by Voltron
Oct 15 2019 6:13am
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

If some are higher than 4.2v, then the BMS isn't working right, as keeping groups from going over 4.2v is one of it's main functions.
by Voltron
Oct 15 2019 1:15am
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

That's another way of saying record your results somehow... So in a year or two you can look back and compare to get a rate of decline in function of the pack over time.
by Voltron
Oct 13 2019 11:02pm
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

But 36v nominal packs aren't 12s... they're 10s? And if you want that voltage you mention, why bring up 10s since its not a 36v pack you're describing any more?
by Voltron
Oct 13 2019 8:58pm
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

Pretty sure most packs designed for 36V are 12S, to support 43 - 44V in use, charge at 49 - 50.4Vch max. No, its pretty standard that going by the mid point cell voltage, 3.6v, that 36v packs are 10s, 48vpacks are 13s, and 52v packs are 14s. And if you charge a 36v nominal, 10s pack to 50v instead ...
by Voltron
Oct 12 2019 11:30pm
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

The ratings aren't a direct indicator of how much you will get, as it changes with the discharge rate. What that is saying is it holds roughly 2.2ah, if you take the electricity out at .2 c discharge rate. It doesn't mean it you put 10 together for 22ah that you can pull 22 amps out for an hour. Its...
by Voltron
Oct 12 2019 11:11pm
Forum: E-Bike General Discussion
Topic: is a motor dedicated to 36v or 48v
Replies: 7
Views: 560

Re: is a motor dedicated to 36v or 48v

The heat build up goes with the watts... running higher volts, but lower amps for the same power can reduce overheating.
by Voltron
Oct 12 2019 12:57am
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

Exactly... I wouldn't go that low on voltage on a 10s though.

I think you can run it on the charger also and see how much you're putting in...
by Voltron
Oct 11 2019 5:56pm
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

You can buy RC wattmeters pretty cheap that will log how much actual watthours you're getting out of a pack...
WattsUp6.jpg
WattsUp6.jpg (76.25 KiB) Viewed 1352 times
by Voltron
Oct 11 2019 5:47pm
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

Using 5 amps isn't the same thing as amp hours... .

Re the one picture, I think they're actually uninsulated solid copper wire, not solder. But yes, that's some big blobs all over.
by Voltron
Oct 10 2019 6:28pm
Forum: Battery Technology
Topic: Increasing range with parallel li ion batteries
Replies: 41
Views: 2410

Re: Increasing range with parallel li ion batteries

These are plucked from the sphere, so sorry if I don't give proper name credit. The first one shows basically what you're talking about... A single row of cells, paralleled together, then hooked to the next row. 25r_welds.jpg The same kind of thing, but soldered, with the red lines showing where som...
by Voltron
Oct 10 2019 12:33pm
Forum: E-Bike General Discussion
Topic: How to test a motor
Replies: 6
Views: 362

Re: How to test a motor

If the battery is actually putting out voltage, you can usually probe the hall wire plug, and the throttle, and see if they're getting voltage to see if the controller is alive. Pictures help... Without seeing the plugs it's harder to tell you what to poke.
by Voltron
Oct 09 2019 11:48am
Forum: E-Bike General Discussion
Topic: is a motor dedicated to 36v or 48v
Replies: 7
Views: 560

Re: is a motor dedicated to 36v or 48v

Re the motor voltage, most systems are designed to run at a legal speed somewhere, so the 36v is wound to come out at roughly that speed. A 48v is wound for less rpms per volt, so it goes the same roughly legal top speed. It won't damage them changing voltage... It just changes the speed they were d...
by Voltron
Oct 08 2019 1:02pm
Forum: E-Bike General Discussion
Topic: haibike power curve modification
Replies: 7
Views: 442

Re: haibike power curve modification

Yes, and big company systems like that are just that...a system, and built for manufacturing efficiency, so every wire and every connector is built just as big as it needs to be. If you up the power thru the software, then maybe your main battery connector melts a little. Then you beef that up, and ...
by Voltron
Oct 08 2019 12:39pm
Forum: E-Bike General Discussion
Topic: BMS defect or unbalanced cells
Replies: 27
Views: 1627

Re: BMS defect or unbalanced cells

Yes, just bulk charging with them unbalanced is bad. If you're going to go that route, you need to either use small lightbulbs or something to discharge each of the high groups, but you really need to stay near it and not forget you're draining a group and let it go too low. Or charge up each low gr...
by Voltron
Oct 08 2019 11:38am
Forum: E-Scooter and Motorcycle General Discussion
Topic: Some help with ebikes
Replies: 21
Views: 1335

Re: Some help with ebikes

Yes, that's the ocean, with some islands in the distance.

Edit.. In commuter mode I just run one battery module which makes it a lot easier to move around when off the bike. But then I don't punch it drag racing cars away from lights to limit the amp draw, which is hard 😀
by Voltron
Oct 07 2019 1:52am
Forum: E-Bike Technical
Topic: How to access and remove the battery of this ebike?
Replies: 36
Views: 1524

Re: How to access and remove the battery of this ebike?

It's these things... Dendrites. The time scale is 42 hours. They grow. How much they grew inside your battery is a guess.

Dendrites_preview.jpg
Dendrites_preview.jpg (207.83 KiB) Viewed 324 times
by Voltron
Oct 06 2019 9:51pm
Forum: E-Bike Technical
Topic: How to access and remove the battery of this ebike?
Replies: 36
Views: 1524

Re: How to access and remove the battery of this ebike?

They're overcharging it to get it to blow up of course, but that's the same kind of currents that will go thru a cell when the dendrites start piercing the separator layers and start shorting out the cell from inside... Again, it's not about charging at low amps or about fuses... It won't be a dange...