Search found 66 matches

by DogDipstick
Jul 23 2019 7:04am
Forum: E-Scooter and Motorcycle General Discussion
Topic: torque steer
Replies: 8
Views: 216

Re: torque steer

Torque steer is something you see on things like trikes with two powered wheels in parallel with each other (like having motors on a tadpole trike's front wheels, or a delta trike's rear wheels), and you apply more power to one wheel than the other--then you get pulled toward teh side with more pow...
by DogDipstick
Jul 22 2019 6:18pm
Forum: General Discussion
Topic: Avoiding spark
Replies: 9
Views: 314

Re: Avoiding spark

Run the current through a mechanical contacter with a resistance across the terminal? Or manually use a short piece of wire connect a piggy back precharge resister into the circuit... before connecting the main leads.. Or buy an antispark connector... or a ssr, maybe would do it. The inrush of curre...
by DogDipstick
Jul 22 2019 6:09pm
Forum: Items for Sale - New
Topic: Assembled Hi-Power LiPo battery packs - any interest?
Replies: 563
Views: 102850

Re: Assembled Hi-Power LiPo battery packs - any interest?

Mr. Jones: Let me ask you this, in your 10yrs of experience, have you ever seen an internal short in a large pouch cell lipo?

I never have.
by DogDipstick
Jul 14 2019 8:38am
Forum: Items for Sale - New
Topic: Assembled Hi-Power LiPo battery packs - any interest?
Replies: 563
Views: 102850

Re: Assembled Hi-Power LiPo battery packs - any interest?

I have always wondered. Why do you build with such small cells (...5Ah), when 15, 24 or even 50Ah cells are readily available? Why parallel (9)cells when one can do the same with one cell strings, or two, cells running in parallel? There are powerful enough NMC I do believe, or am I wrong? My NMC EV...
by DogDipstick
Jul 13 2019 12:58pm
Forum: Battery Technology
Topic: voltage drop under load (maybe a simple question?)
Replies: 28
Views: 818

Re: voltage drop under load (maybe a simple question?)

I drop about a volt ( 1v ) when pulling 20 amps @ 58v. 15 Ah Lipo NMC pack. To know the amps used you need to know more than the voltage droop and the capacity.
by DogDipstick
Jun 25 2019 7:11am
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 775
Views: 91827

Re: kWeld - "Next level" DIY battery spot welder

For you guys who have problems with lipos... Who need to rebuild them.. ... I keep blowing my lipos, will i reduce the time required to make the weld by increasing their voltage? And there by reducing the heat and stress on the thin aluminum terminals Im currently at 3s and can make a 5s batters fro...
by DogDipstick
Jun 13 2019 4:22am
Forum: Motor Technology
Topic: RC ESCs in a real size motorbike? How stupid would that be?
Replies: 7
Views: 370

Re: RC ESCs in a real size motorbike? How stupid would that be?

I wonder if it has Active freewheeling for low loads ( sycronious rectivication)....
For 550$ it better lol.
by DogDipstick
Jun 13 2019 3:47am
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 775
Views: 91827

Re: kWeld - "Next level" DIY battery spot welder

But I shoudln't get political here, just wanted to share this. I have recently upgraded the kWeld production tester 8) IMG_20190523_121819.jpg Hello again friend... I have to ask... excuse me if this is superfluous... but being an engineers son, and laboring for his small establishment... I have to...
by DogDipstick
Jun 09 2019 4:58am
Forum: Battery Technology
Topic: Adhesive-backed copper tape ampacity
Replies: 10
Views: 426

Re: Adhesive backed copper tape ampacity

NO. Resistance will be jacked... It says in the sheet, 500mOh / copper to copper.. and more any other metal. Ive tried this before, with different kinds of taps, and concluded adhesive is no good for amps and sheet doesn't connect easy. I have seen foil thick enough to solder to. When you study copp...
by DogDipstick
Jun 02 2019 8:40am
Forum: E-Bike Technical
Topic: 2019 Motor Simulator, Mid-drives and other updates
Replies: 35
Views: 2776

Re: BBS02 and BBSHD

This graph here shows the unloaded crank RPM as a function of the power supply voltage. BBSxx rpm vs V Graphs.jpg The BBS02 is a faster motor winding at about 3.27 RPM/V, compared to ~2.71 rpm/V for the BBS02. Justin, Am I reading this graph incorrectly? It looks like the BBSHD is the faster windin...
by DogDipstick
Jun 01 2019 7:40am
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 217
Views: 35709

Re: Spot Welding Copper Strips to 18650 Battery Cells

Old sheet metal workers trick for spot welding aluminum too...
by DogDipstick
May 26 2019 11:27am
Forum: Battery Technology
Topic: Salvaged EV cells index: Leaf, Volt, Tesla, Zero, etc
Replies: 59
Views: 15552

Re: Salvaged EV cells index: Leaf, Volt, Tesla, Zero, etc

Problem with Greentecauto is that they do not provide specs of batt modules very bad for DIY crowd. You have to dig yourself on Google to find out specs Not like HibridAutocentre which provide detailed specs of every module they sell I have had a good discussion with GTA... He is nice once he figur...
by DogDipstick
May 20 2019 7:51am
Forum: Battery Technology
Topic: Calling all battery surgeons! Have you seen this?
Replies: 23
Views: 827

Re: Calling all battery surgeons! Have you seen this?

Yeah I would wonder that tooo. Why is it going past 4.2V? Should not absolutely. What are you using to check voltages? A multimeter? Also, if you have 13 reading good, but one reading over, is that not a 14s battery? Or a typo? Could be a lower capacity group in the string that is making the rest no...
by DogDipstick
May 07 2019 11:45am
Forum: Battery Technology
Topic: 65A on 8AWG 1.5m length (hot?)
Replies: 23
Views: 887

Re: 65A on 8AWG 1.5m length (hot?)

Live on the edge. 250 circular mil / amp. ( 700 for buildings lol) Short runs, and remember 2 (10ga) > 1 (8 ga). :)
by DogDipstick
May 07 2019 8:40am
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 775
Views: 91827

Re: kWeld - "Next level" DIY battery spot welder

Beautiful, Tatus'69. Thankyou for the input, I do "grasp at straws" from time to time, and correction is learning. As for the new project, Wunderbare Neuigkeiten! I will not have to try give my home-made batteries away anymore to unsuspecting friends for testing...! ( anybody wanna battery to test? ...
by DogDipstick
May 05 2019 6:46pm
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 775
Views: 91827

Re: kWeld - "Next level" DIY battery spot welder

Let us look at something, For a moment: and I wish for Tatas to correct me if he could, for I am an amateur and know very little where it comes to the laws of electricity: I wish for a math lesson. This machine is capable of input in the area <30v Dc. Presuming we are diehard spot weldors, and have ...
by DogDipstick
May 01 2019 9:26am
Forum: E-Bike Technical
Topic: Building first lipo pack - Drift Trike
Replies: 21
Views: 729

Re: Building first lipo pack - Drift Trike

Depends on the manufacturer and the quality... and how low you go. Cells wander the lower you go, then when charged dont come back together easily without some serious taper current such as C/20 or C/50.... most balance chargers balance taper @ C/5. This accuracy in balancing is not nesccesary for s...
by DogDipstick
Apr 30 2019 8:23pm
Forum: E-Bike Technical
Topic: Building first lipo pack - Drift Trike
Replies: 21
Views: 729

Re: Building first lipo pack - Drift Trike

Thanks for the C rating feedback. I thought that 12C for 5ah would be fine as its 12*5=110a continuous, but good to know what happens in reality. The 25C was my original choice but changed my mind because the other pack was lighter. The trike will only be a toy so long running time isn't important ...
by DogDipstick
Apr 30 2019 8:56am
Forum: Battery Technology
Topic: Spot welding LIPO cell terminals
Replies: 7
Views: 330

Re: Spot welding LIPO cell terminals

One tab is tinnned copper and one is aluminum. Mechanical connections are just as good. Your connections are 30% of the bulk of the pack? Mine are like an extra 5 %. You burn the tabs easy. then the cell is toast. Impropper technique, overheating, under fluxing can all add up to this. Then you just ...
by DogDipstick
Apr 30 2019 8:47am
Forum: E-Bike Technical
Topic: Building first lipo pack - Drift Trike
Replies: 21
Views: 729

Re: Building first lipo pack - Drift Trike

50A should be nothing for the 5Ah 12C cells... to a point. Continuous use would stress the packs lifespan but you should be ok for a while. For example, I hit my 5Ah packs 3-=65C packs w 3000W all summer... Drain them in 4 min... each at a time... but only the ones that go down less than to 50% are ...
by DogDipstick
Apr 30 2019 1:47am
Forum: E-Bike Non-hub Motor Drives
Topic: IT'S ALIVE...... BBS02HD!!
Replies: 28
Views: 3073

Re: IT'S ALIVE...... BBS02HD!!

of the parts we sell the least of. Take a fat bike and ride in deep snow and throw full throttle at it and you can be like Karl and melt a gear. The only other meltdowns I’ve seen are from riders that run an 02 like it were a one speed moped. Keep it wound, up and like my 3 pre 3077 FET versions, a...
by DogDipstick
Apr 25 2019 9:16am
Forum: Items for Sale - Used
Topic: Chevy Volt individual Cells FOR SALE. 10C 15Ah
Replies: 47
Views: 3498

Re: Chevy Volt individual Cells FOR SALE. 10C 15Ah

I broke 2000 amps with my battery. Consistently with attempts to weld copper. My goal is to get as close to 2000A / weld, and weld very conductive metals in very short intervals. The K-welder is overcurrent protecting. I must build a smaller ( >6s) battery now to run it. It is a good test of the int...
by DogDipstick
Apr 25 2019 8:31am
Forum: Battery Technology
Topic: kWeld - "Next level" DIY battery spot welder
Replies: 775
Views: 91827

Re: kWeld - "Next level" DIY battery spot welder

The only thing getting warm is the silicone 8Ga. Either weld at a pace that allows that, or consider putting a fan on it. I'd strongly advise putting it in an enclosure, however crude. With these energy levels just a bit of stray copper etc finding it's way onto the board could result in a spectacu...