Search results

Date Relevance Most replies

  1. C

    Battery design advice required

    That's exactly what I've been trying to avoid with both the X and U patterns. I've been experimenting with my spot welder on some dead cells, and I've found that nickel-on-nickel welds are very weak. The same settings that can form a strong weld for nickel-on-cell creates very weak welds that...
  2. C

    Weld 2P battery in an X pattern?

    I 3D printed a top and bottom plate for the whole battery. This is my first time 3D printing and I wanted to leave enough "meat" there for the 3D printer to be able to print it properly. Maybe I'll try it again with narrower spacing. I went with rectangular (vs staggered) layout to favor a...
  3. C

    Battery design advice required

    All that being said, based on feedback in a different thread, I am considering a U shape now also. As previously stated, my main reason for the X was to avoid trying to weld the parallel connections over top of the series connections, since there isn't enough room on the positive terminal for...
  4. C

    Battery design advice required

    dont know why you write .07% which is a tiny amount. doing the x on the rectangularly arranged cells would be 30% more strip needed and 30% more resistance. Yes, it is 30% more nickel and 30% more resistance. My calculations showed a 39% increase in losses (1.28 Watt vs 0.92 Watt). The 0.07%...
  5. C

    Weld 2P battery in an X pattern?

    Thanks guys! Looks like I'll be going this way! I also discussed this in another thread where someone had somewhat related question, and there I calculated the additional loss from the longer runs of copper. Unless I screwed up the math, it was negligible: 0.07% less efficient for the whole...
  6. C

    Battery design advice required

    Thanks serious_sam! I think I'm okay for quantity of nickel. I'm using 8mm x 0.2mm pure nickel, and the battery will drive an TSDZ2 which can only sustain 16-20 A continuously, so 8-10 A per strip. If I did the math right, it looks like the additional losses from the extra distance are pretty...
  7. C

    Battery design advice required

    Here's a revised version with the polarities marked (for the "top" end of the cell that you can see in the diagram): For the bottom right group, I've shown the parallel path in blue, and the series path in magenta.
  8. C

    Weld 2P battery in an X pattern?

    Thanks. Yes it is a slightly longer run. I'm going with fairly thick 0.2mm pure nickel, and expect the sustained load to be <= 10A per strip (20A for the battery), usually way under. I don't expect losses/heating in the nickel to be an issue. I'm more concerned about if there is any...
  9. C

    18650 spot welding -how to- ULTIMATE REPOSITORY

    Hi all, I was wondering if there's any reason I should not weld a 2P battery pack in an "X" configuration, to avoid layering nickel strips and to reduce the amount of welds. I made a separate post here about it with more detail, but it has only gotten one response so I hoped I might get a bit...
  10. C

    Battery design advice required

    I'm doing a 14s2p in a 7x4 configuration. My plan (and would love feedback here) is do this: Green are strips on top, red are strips on bottom, black dots are weld points. You can see at the split/fold (top of the picture), I intend to weld the inner two cells with a strip, and the outer...
  11. C

    Weld 2P battery in an X pattern?

    Hi there, I'm building a 14s2p battery. I was wondering if there's any reason I couldn't weld the nickel strips in an X pattern, like shown in blue, rather than a typical rectangle as shown in green? The reason is, it would reduce the number of strips I need to weld (2 strips per quad, rather...
  12. C

    Feedback on spotwelds?

    I just measured the wires: 1.8mm diameter, so about 13awg. Mine also jump around on each weld, and the tip gets uncomfortably hot after a few welds. I suppose I could look at upgrading this, but it's a bit annoying, as I specifically bought this unit since it was a well-liked ready-to-go unit...
  13. C

    Feedback on spotwelds?

    Two pure copper wires, insulated with shrink wrap, rounded and sanded a bit to work well at a 45 degree angle. Here's a video of someone else using the welder from the other thread; I use it pretty much like he is doing. https://www.youtube.com/watch?v=voWpcxBbxoA Yeah, they're dead 0v cells...
  14. C

    Feedback on spotwelds?

    Sorry, beyond the suggestion to clean and scuff the nickel, I didn't understand the reset of your suggestion. The welder is linked at the top of my original post.
  15. C

    Feedback on spotwelds?

    Hi all, I have this spot welder: https://endless-sphere.com/forums/viewtopic.php?f=14&t=89076 I'm powering it with a 5000mah 50C sustained 100C burst 3S LiPo, welding 0.2mm pure nickel strips onto 18650s. According to the official documentation and what I've read in forums about this welder...
  16. C

    Dropped battery, one cell dented. Trying to understand failure mode.

    Thanks! Definitely won't charge it again. I was just asking whether it's as harmeless as a 9s2p battery for sitting around doing nothing until I get the cells replaced.
  17. C

    Dropped battery, one cell dented. Trying to understand failure mode.

    Hi there, I have a 10s2p battery without hard case (just shrink wrap). I dropped it, and now the negative terminal of one of the cells in the last pair on the positive end of the battery is dented. Photo attached. I first noticed an issue when the battery voltage was suddenly so low that my...
  18. C

    TSDZ2 mid drive with 860C, 850C or SW102 displays only -- Flexible OpenSource firmware (Casainho code only)

    https://github.com/OpenSource-EBike-firmware/TSDZ2-Smart-EBike/blob/master/src/motor.c#L482 Is this why battery max current isn't being respected during field weakening?
  19. C

    TSDZ2 mid drive with 860C, 850C or SW102 displays only -- Flexible OpenSource firmware (Casainho code only)

    Hi guys, I have two small issues with the 1.0 firmware. Not sure if it is 1.0 related as this is the first firmware I've tried (I just got the motor). Issue 1: Speed always reads zero I have confirmed it is not a hardware issue. I've tried two different speed sensors, and have adjusted the...
  20. C

    TSDZ2 slight resistance, grinding sound 1 per revolution

    Hi there, I just got a brand new TSDZ2 from eco-cycles. It is working, but have noticed that the resistance when turning the cranks is not continuous all the way around. It is smooth all the way except one spot, where it has a bit more friction. It's not a huge amount, but you can feel it when...
  21. C

    TSDZ2 not reading speed

    Hi there, I got the OSF TSDZ2 kit from eco-cycles, flashed with the latest 1.0 stable firmware. Got it all put together this weekend and it works pretty well, but I'm having an issue: the speed always reads zero. I have tried: * Dis/Re-connecting the sensor * Swapping the speed sensor for...
  22. C

    Bafang G310 with Shimano 8/9/10/11 speed MTB cassette

    Thanks for the confirmation! That matches what I suspected. I actually managed to confirm it yesterday myself by popping by at Grin with an 11speed mtb cassette and doing a test fit. It fit perfectly without the extra spacer into my CX frame. Ordered the kit! Stoked!
  23. C

    Controller current draw vs. motor current draw

    Thanks for the responses guys. Here's a sim screenshots at 20kph 60% throttle, withing the 10A sustained of 2xLiGo And another at 25kph 76% throttle, within the 20A Max of 2xLiGo Limiting the power probably won't be an option as I'm going for a super minimal build - just a thumb...
  24. C

    Bafang G310 with Shimano 8/9/10/11 speed MTB cassette

    Hi all, I'm considering converting a 135mm dropout CX frame to an ebike using the G310 motor. The current drivetrain is a 10 speed shimano road cassette in the back. I'm not sure what to make of this blurb from the Grin info page for the motor...
  25. C

    Controller current draw vs. motor current draw

    Hi all, I'm considering doing a minimalist ebike conversion using the G310 kit from Grin: https://www.ebikes.ca/shop/electric-bicycle-kits/bafang-g310-311/rear-g310-kit-basic-throttle.html The kit comes with a 20A controller, and I was planning to do 2 x LiGo batteries. Each LiGo can handle...
Back
Top