Search found 1393 matches

by Hummina Shadeeba
Feb 14, 2018 10:43 pm
Forum: Battery Technology
Topic: 3D printed copper compression battery
Replies: 15
Views: 701

Re: 3D printed copper compression battery

liked this design last before getting a spot welder. with the bands it wouldn't fit the skate deck I want to use. I like the guards allowing a loop of copper to come up and I imagine relieve physical strain.
by Hummina Shadeeba
Feb 14, 2018 10:30 pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 160
Views: 14435

Re: Spot Welding Copper Strips to 18650 Battery Cells

this one is most versatile I've see and only 2 cells. really nice design. easy to print. https://www.aliexpress.com/item/High-Quality-18650-Battery-Holder-Bracket-ABS-Material-Anti-Vibration-Cylindrical-Battery-Spacers-Holder-18650-Batteries/32620037404.html?spm=2114.search0104.3.299.1e5dfec3nCN7fw&...
by Hummina Shadeeba
Feb 14, 2018 2:26 am
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255851

Re: Definitive Tests on the Heating and Cooling of Hub Motors

Why would running such a motor amp to battery amp ratio be beneficial? Just reduced? The typical high 2.5:1 Phase to Battery current limit ratio so commonly used is a main source of heat problems. The reason is because it too often creates high phase current when you don't want it, eg at lower spee...
by Hummina Shadeeba
Feb 13, 2018 5:30 pm
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255851

Re: Definitive Tests on the Heating and Cooling of Hub Motors

Why would running such a motor amp to battery amp ratio be beneficial? Just reduced?
by Hummina Shadeeba
Feb 12, 2018 3:06 am
Forum: E-Bike Technical
Topic: Definitive Tests on the Heating and Cooling of Hub Motors
Replies: 1982
Views: 255851

Re: Definitive Tests on the Heating and Cooling of Hub Motors

John in CR wrote:
Feb 11, 2018 4:45 am


Of course the easiest route to cooler temps (other than proper controller settings) remains the least used. That is directing more air flow toward the hubmotor shell.
or a bigger motor which will have a lower electrical resistance
by Hummina Shadeeba
Feb 11, 2018 12:54 am
Forum: E-Bike Technical
Topic: Bafang BBS02, DROK and 60 volts
Replies: 3
Views: 112

Re: Bafang BBS02, DROK and 60 volts

why use the step-down drok instead of get a power supply at the voltage you want?
by Hummina Shadeeba
Feb 05, 2018 11:23 am
Forum: E-Vehicles General Discussion
Topic: i can fit 6 more cells, why shouldn't I?
Replies: 5
Views: 180

Re: i can fit 6 more cells, why shouldn't I?

du. don't know why 11 got skipped. good idea! I'm too used to lipos coming in packs of 2
by Hummina Shadeeba
Feb 04, 2018 12:47 pm
Forum: E-Vehicles General Discussion
Topic: i can fit 6 more cells, why shouldn't I?
Replies: 5
Views: 180

Re: i can fit 6 more cells, why shouldn't I?

ok thanks. was think of 12s4p and 48 cells vs 10s5p and 50 cells and if there are any variables I'm missing. 5% more watthours and probably safer for the esc components vs a bit bigger current draw. Maybe in the long run the 12s cells would last longer. its spitting hairs and they both work but wond...
by Hummina Shadeeba
Feb 04, 2018 2:43 am
Forum: E-Vehicles General Discussion
Topic: i can fit 6 more cells, why shouldn't I?
Replies: 5
Views: 180

i can fit 6 more cells, why shouldn't I?

48 cells gets me 12s4p but I could fit 54 cells and I have them. Whats the story of the 12s4.5p?
by Hummina Shadeeba
Feb 04, 2018 12:37 am
Forum: Battery Technology
Topic: Spot Welding Aluminium
Replies: 17
Views: 746

Re: Spot Welding Aluminium

Al from soda/beer cans is 100% coated with prtective epoxy laquer..both sides.. So a lot of prep will be required. :o And the thickness is less than 0.1mm in the side walls, or 0.25 mm in the center of the bottom "dome" eww. i thought Coke was acidic enough to eat through stuff, why arent we all dr...
by Hummina Shadeeba
Jan 19, 2018 4:40 pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 160
Views: 14435

Re: Spot Welding Copper Strips to 18650 Battery Cells

I have some .14mm copper and it is weak but maybe that's actually a good thing. not saying necessarily and would depend on each instance but if the strip can bend then it isn't putting the strain on the welded connection to the cell
by Hummina Shadeeba
Jan 17, 2018 3:04 am
Forum: Stand-up E-scooters and E-skateboards
Topic: motor wires interfere with reciever?
Replies: 5
Views: 131

Re: motor wires interfere with reciever?

aren't the antennae kind of specific or fragile? can you simply extend the wire with another soldered on wire?

I thought I heard somewhere motor wires could interfere..any second opinions?
by Hummina Shadeeba
Jan 17, 2018 12:03 am
Forum: Stand-up E-scooters and E-skateboards
Topic: motor wires interfere with reciever?
Replies: 5
Views: 131

motor wires interfere with reciever?

will the motor wires interfere with my receiver antenna beside it?
by Hummina Shadeeba
Jan 17, 2018 12:02 am
Forum: Stand-up E-scooters and E-skateboards
Topic: Direct VESC V4.12
Replies: 15
Views: 1177

Re: Direct VESC V4.12

but he does post the guide and says its easy to do! I've never done it.
by Hummina Shadeeba
Jan 13, 2018 4:32 am
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 160
Views: 14435

Re: Spot Welding Copper Strips to 18650 Battery Cells

it looks like the "boss level" welder has no trouble with .1mm copper strip and this guide, which seems more conservative than most, shows .1mm nickel x7mm strip doing 3amps comfortably, so with copper being 4 times as conductive couldn't I do a .1mm x 28MM FOLDED STRIP and that would net me 48 amps...
by Hummina Shadeeba
Jan 13, 2018 2:53 am
Forum: Battery Technology
Topic: Spot Welding Aluminium
Replies: 17
Views: 746

Re: Spot Welding Aluminium

adding another higher resistance material in a spot welding sandwich maybe creates the heat needed to do the most conductive materials: http://bbs.homeshopmachinist.net/thread ... pot-welded
by Hummina Shadeeba
Jan 07, 2018 7:30 pm
Forum: Battery Technology
Topic: DIY nickel-plating onto copper cell connections
Replies: 29
Views: 2018

Re: DIY nickel-plating onto copper cell connections

new info for me is that sodium benzotriazole is a good copper corrosion inhibitor. you can just dip the copper. haven't done it yet. electroplating is pretty damn fun though
by Hummina Shadeeba
Jan 03, 2018 1:55 pm
Forum: Battery Technology
Topic: trickle charging lithium
Replies: 3
Views: 190

Re: trickle charging lithium

thanks guys for the info and links above, there's a good one. The cells at 4.2 either on the charger or not makes no difference. makes sense.
by Hummina Shadeeba
Jan 02, 2018 11:32 pm
Forum: Battery Technology
Topic: trickle charging lithium
Replies: 3
Views: 190

trickle charging lithium

its said that trickle charging is not only bad for cells but even dangerous but what exactly would trickle charging be? When I bulk charge with a meanwell or some other constant voltage source and the pack is getting close to the supply voltage the amps going to the battery will go way down to a tri...
by Hummina Shadeeba
Dec 25, 2017 3:01 am
Forum: Battery Technology
Topic: 3D printed copper compression battery
Replies: 15
Views: 701

Re: 3D printed copper compression battery

I don't think heat will be a danger with any rubber: http://www.jjshort.com/Rubber-Properties.php I've got all these bands coming from amazon and now like the inner tubes idea best. crafty. I imagine cheaper. Faraday discovered Isobutylene or butyl. I don't think a tape would be as good because it s...
by Hummina Shadeeba
Dec 23, 2017 3:54 am
Forum: Battery Technology
Topic: 3D printed copper compression battery
Replies: 15
Views: 701

Re: 3D printed copper compression battery

I'm saying if youre using shrink wrap and a heat gun to get it on that's a very high heat which the rubber bands wont like
by Hummina Shadeeba
Dec 22, 2017 11:38 pm
Forum: Battery Technology
Topic: 3D printed copper compression battery
Replies: 15
Views: 701

Re: 3D printed copper compression battery

I think cooking the bands under shrink wrap could be possibly ruinous with the heat. epdm rubber bands seem the most robust and will use those. Each of theses packs of 4 rubber banded cells will probably be strapped down with Velcro by their center. they use 17mm copper strip .5mm thick ( 8.5mm2) wh...
by Hummina Shadeeba
Dec 20, 2017 7:13 pm
Forum: Battery Technology
Topic: 3D printed copper compression battery
Replies: 15
Views: 701

Re: 3D printed copper compression battery

The tape might not be the best material but I’ve got some super resilient rubber bands on route. I believe a band could for sure keep compression for a very long time. After so many miles with the bands I can take one off and compare its strength to a new one to see
by Hummina Shadeeba
Dec 19, 2017 5:26 pm
Forum: Battery Technology
Topic: 3D printed copper compression battery
Replies: 15
Views: 701

3D printed copper compression battery

how do you think it will go?! I will stack them and 6 long 12s. 4p. I can add more copper foil and plan to but now it's at a single thick .5mm with the dimples pressed in on an abs printed press. i'll go thinner on top since info on ES says it contours better for better connection. how to get compre...