Search found 831 matches

by Nobuo
Jul 05 2016 5:21pm
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

I made this calculator for a mosfet type welder and for batteries (specifically JP welder + battery source) I put a good amount of work into it, so please give credit and keep my contact on there if you modify it. And distribute this read only link. https://onedrive.live.com/redir?resid=6 ... ile%2...
by Nobuo
Mar 28 2016 4:25pm
Forum: Large EV General Discussion
Topic: NOBUO-01, solar assisted small EV
Replies: 8
Views: 2758

Re: NOBUO-01, solar assisted small EV

I finally edited the construction video, a small sum for the most important parts, hope you enjoy it!

by Nobuo
Mar 28 2016 9:37am
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

In laptop packs I've found always 0.3mm of pure nickel
by Nobuo
Mar 24 2016 1:13am
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

72V can easily kill a human, the more chance the more amps you receive, with a li-ion battery you have all you need to die with. However human skin has enough resistivity to don't make this kinda happen, unless you have your hands or skin covered with an enough conductivity salts solution or similar...
by Nobuo
Mar 15 2016 2:53am
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

Depends closely with your detail level construction. Cells are perfect cylinders, if you make good shapes and patterns where cells are very exactly placed, the weight will perfectly distributed if the battery have an impact for example, and is almost impossible that both insulators of two consecutiv...
by Nobuo
Mar 14 2016 10:34pm
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

Neither hot glue/ melt silicone or spot welding will make an appreciable harming heat. The important thing is the capacity of the cell to spread the heat quickly so the chemicals have not an increased temperature. All the cells is covered with a metal that will spread the heat quickly over all its s...
by Nobuo
Mar 14 2016 9:25pm
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

Is there an easy way to remove cells that are hot glued together? Put the glued cells into the freezer (-18ºC or less) for 12h to 24h. Cover all into a semi-vacuum bag (standard plastic bag tied) to avoid a very high temperature change and humidity. Then you can very easily rip off them, even with ...
by Nobuo
Mar 10 2016 1:43pm
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

OP here also the builder :o In that case specially the battery was made first sticking and welding 15p blocks, and then sticking each other up to the final shape. As you don't have time to put 8 strips of silicone and then stick the modules (silicone would harden), you are obliged exclusively in tha...
by Nobuo
Mar 03 2016 6:41pm
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

From what I observed during my initial tests, it is very important how you weld the second stripe. The current does not like to flow through a small spot weld and chooses to flow mainly through the first layer of the metal stripe. I was testing that with steel stripes I couldn't reach 50% "efficien...
by Nobuo
Mar 03 2016 10:50am
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

Nobuo, how is doubling up with nickel strip compare with a single thicker piece? For example, using two .15 x 7 mm strip vs using a single .3 x 7 mm strip Do you think that you would get close to 95% - 99% of the single .3 mm strip by using two .15 mm strips? The reason I ask is because .3 nickel i...
by Nobuo
Mar 02 2016 10:43pm
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

Won't current sharing between cells depend on the placement of the series links? i.e. if you only have 2 series links for 8 paralleled cells, then the cells not next to the series links will need to send their current through the nickel first before it reaches the series link. Cheers Current sharin...
by Nobuo
Mar 01 2016 2:16pm
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

Paralleling connections use too low current sharing, taking into account you are using new cells for the same model, you don't need even 0.15mm pure nickel. 0.1mm is more than enough for paralleling connections. You need only the right size in the main leads cathode and anode terminals, depending o...
by Nobuo
Feb 29 2016 5:48am
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

I just tried to weld .3 99% nickel and I have discovered that there is no way I'm going to use .3 99% for my build. It is too thick and too difficult to get consistent welds. The welds burn too easily also. Then when I tried to up the power of my welder I blew the fets. So now I have to find an alt...
by Nobuo
Feb 22 2016 8:42am
Forum: Battery Technology
Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
Replies: 759
Views: 156930

Re: 18650 spot welding -how to- ULTIMATE REPOSITORY

So I bought the Sunko 709A upgraded which is one of the spot welders recommended for the USA, but the two pins on the welding head weld unevenly. One side will burn through the .15 nickel strip while the other does a fine weld. The one pin is stronger than the other. Welds are inconsistent as well....
by Nobuo
Feb 20 2016 3:52am
Forum: Stand-up E-scooters and E-skateboards
Topic: Electric Penny Board
Replies: 1
Views: 755

Re: Electric Penny Board

I think is closer as a toy than a real e-skate, I would look for further solutions
by Nobuo
Feb 20 2016 3:48am
Forum: Battery Technology
Topic: BMS thermal management
Replies: 3
Views: 489

Re: BMS thermal management

nice work, though I've never seen bleeding resistors (40mA to 60mA) generating too much heat. It only happen when the battery is almost full charged and the balancing circuit activate, could you confirm this?
by Nobuo
Feb 20 2016 3:45am
Forum: E-Bike Technical
Topic: installing HS 2540 correctly
Replies: 2
Views: 406

Re: installing HS 2540 correctly

1) usually yes, however with direct drive hubs, you can work on both directions with the same performance. 2) if putting both spacers "inside" makes the axle to be inserted with some pressure, this is just perfect. spacers could be put in both position, inside or outside the arms, however you need t...
by Nobuo
Feb 20 2016 3:40am
Forum: E-Bike General Discussion
Topic: question about kw rating for kelly controllers
Replies: 2
Views: 313

Re: question about kw rating for kelly controllers

you are right, that would be a bad rating. Could you share a link with full specs of each one?
by Nobuo
Feb 20 2016 2:48am
Forum: E-Bike Technical
Topic: Digital Heinzmann sequence flashing LEDs
Replies: 1
Views: 294

Re: Digital Heinzmann sequence flashing LEDs

a video of the blinking leds would be enormously appreciated
by Nobuo
Feb 20 2016 2:47am
Forum: E-Bike General Discussion
Topic: Me1003 with 600a 100v controller w/ regen
Replies: 4
Views: 640

Re: Me1003 with 600a 100v controller w/ regen

it should work, which motor model are you using?

also i'm curious about what kind of battery are you using to feed such power? :o
by Nobuo
Feb 20 2016 2:42am
Forum: Battery Technology
Topic: Comparative Testing Study: Commercial 18650-Format Li-Ion
Replies: 1
Views: 476

Re: Comparative Testing Study: Commercial 18650-Format Li-Io

All the data show what other tests use to make in conclusion. Budget batteries never worth, if you take into account the useful energy along its lifetime, you pay more for each Wh. Otherwise all the batteries wear more or less, but it doesn't show how different is the wearing at high rates (higher t...
by Nobuo
Feb 20 2016 2:30am
Forum: Battery Technology
Topic: Battery meter
Replies: 1
Views: 402

Re: Battery meter

Really interesting, what I don't find is what kind of displays they suggest to use to output all the data.

Thanks for sharing
by Nobuo
Feb 20 2016 12:44am
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6794

Re: Custom Controller Heat sink Calculations

Could you share some of the dimensions of your casing? For such power output I don't see a real heat problem situation
by Nobuo
Feb 20 2016 12:11am
Forum: E-Vehicles General Discussion
Topic: High Amp Master Switch
Replies: 4
Views: 831

Re: High Amp Master Switch

1a: the best one is to don't need to use one. For 100A the switch must be enormous and will wear fast (unless you mount any pre-charge resistor). Controller use to have a switch On / Off function, use it preferably, and disconnect the battery for storage. Otherwise you can use on of those http://g02...
by Nobuo
Feb 19 2016 10:38pm
Forum: General Discussion
Topic: Home made batteries
Replies: 1
Views: 351

Re: Home made batteries

Mainly say that for ebike purposes NCR18650B is not a recommended cell, because its weak discharge rate capability, Can be used with an acceptable performance for continuous discharge under 1.5C. About that holders, are not the ones for battery building, it will make the battery really huge as I see...