Recent content by radad

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Crucial Question: Could the cell death be a effect of the NIB method as it? Nikola Tesla is my hero. Unfortunately i'm like the dumbass under educated Edison just experimenting over and over. But I'm doing the best with what little theory I do understand. I'm glad people are noticing this...

Every things been going great until a recent ride showed a huge voltage drop. I disassembled the pack and tested every cell. In the last parallel positive row, the corner cell was bad, measuring .4v I'm hoping it was a factory defect. I tested all batteries as shipped @3.63v then mass group...

Yes I have some measurements off positive. Using a known method to measure mohm (using nominal 220ohm resistor and a 5v ps yielded imprecise measurements so I doubled to 440ohm) and got the following: 1 battery, nib on + terminal, cu, nib on top of cu(.012x1x1"). Measurement from battery + to 1...

Yea literately the slow boat from china

GNG, 1000W 48V BB-drive with lightingrods 25mm belt drive

OMG!!! My battery order from 5/5/14 @fasttech arrived. I got a boat load of sammy 20-r's now. Also got some 1.4" wide pure nickel strip. Now I can try the only configuration I haven't tried - magnets on the bottom only. Preliminary test show the same resistance with ni as cu. But one thing for...

wiresim thats a good idea I'll give it a go! I can only imagine how well this setup would work with buckypaper as the bus!!! ahhh I just had a techorgasm

Yea thats was the old method. But ver 5.21 the current does flow up through the magnet on the battery terminal to the busbar.

I did already tried the crazy glue idea weeks ago as posted. Not a good idea, unless you want to replace the bus bars after removal. Think about it, try and remove bus with 12 magnets holding it down. My current method is far superior. The pack is to be holding up well, but resistance of...

X-speed thanks so much for your major contributions!!! Ok I got some mv measurements from cell to cu - lowest 1.5mv, highest 3.4mv. Most are right at 2.0mv avg 2.2mv (10 points tested). Upon cleaning the 3.0+contacts mv dropped to around 2mv. So I assume that 1.5mv is a prefect contact point...

My new 20r are measuring right around 50mohm. I just learned this: ri=(v1-v2)*r/v2 v1 = 3.63 v2 = 3.61 r = 10ohm/10w ceramic I've read 20r's are anywhere from 13mohm to 50mohm. But I'm seeing a consistent 50mohms. The measurements you instructed I tried with a 5 amp charge current, so I don't...

Well I'm on battery pack rev 5.21 and I'm finally happy. X-speed I took your advice and did what mechanically felt best. On ver 5.20 (series first w/22ga balance wire) worked great except it blew out 4 balance wires during assembly (damm magnets), so I can assure that the balance wire will act...

I had to glue the crappy 18650 spacers together with crazy glue. Now I have a somewhat rigid grid to work with. Previous pack config with longer parallel buses was more prone to popping out a nib when being flexed. Now do to the crazy glue and shorter bus length its much more mechanically solid...

Wow nice contribution Xspeed! I knew this would work the first time I went down the road on a temp foam/duct tape clamping system. Just didn't have the equipment & expertize to prove it. How are you measuring milliohms ? is it off the shelf or diy? Also could I calculate the entire packs...