Yes, they are super nice. Unfortunately I made some mistakes building the pack and recently tore it all apart. I plan to make a video about it to show some things to be aware of when using these busses. I burned some holes in my cells during spot welding because I was in a rush and not making sure everything was seating properly. Because these are 1mm thick copper, they are rather stiff and need extra precaution when applying the correct amount of force on the probes. Long story short, i was using the standard method if press hard to seat the nickel on the cell, then relax pressure so it can get a nice weld. Unfortunately on some welds the nickel actually pulled away from the cell and that gap caused a lightning bolt from hell and burns a hole in the bottom of some cells. It was a combination of careless steps on my part, getting in a rush to get done. 1. Not having proper workbench. You need a sturdy flat work surface to make sure the cell holders are fully seated. If not seated then the nickel has a hard time reaching the cell. 2. Not making sure the cell holder is fully seated. With regular nickel you can sort of get away with it because it will bend and yield easily, but these 1mm copper plates sit on top of the tiny triangles and the nickel is a U-shape which dips down to the cell. If the cell holder isn’t seated, the nickel does want to lay flat without a lot of force on the probes. 3. When it doubt, use more pressure not less pressure on the probe. A weak “dud” weld is better than a hole. Lol 4. Time your time. Take a break when needed. I let myself get in the “get ‘er done” mode instead of quality assurance mode. 5. If possible order a “test buss” with 2s2p (2x2) so you can test it with your cell holder and practice with some old cells to get the right spot welder settings.
Are you using a K-Weld spot welder? I can imagine those very stiff bus bars dont give you any play. They really look nice. Those busbars are ready for the new gen Molicel 21700 P45 and P50!
@@718og , this video shows the same welder I have. It seems to do good. I haven’t tried the copper-under-nickel with it yet to see if it has enough power for it. These busses were overkill because i had ideal cell arrangement, so the 1mm thick copper on a 100mm wide series connection means i had 100mm^2 total, or 20mm^2 per cell, basically like using 5x AWG6 wires to make the series connection. No cell on the world needs thar much, lol. The 0.3mm^2 would have been more than enough for a perfect arrangement, but for tricky arrangements where you want to connect bricks that are 2x3 at the 2x border, basically a 2x6 buss, now the 1mm thick starts making sense because 3 cells x 45a (135a) are going across that 20mm2 buss. My basic rule of thumb is 1mm^2 of copper for each 10a, so the 1mm thick could connect 4cells deep on each side. The company custom makes each set and sends you the drawing to verify. I went with simple 16s5p because my battery box fits 5x16 rectangle, and that gave me 60v which is what I wanted. But if I wanted 72v, 20s4p, i could have run a set of 2s4p busses (2x4 shape) down one side and then come up the right side with 1x8 busses connecting the last 4 sets of 4p. For these which are essentially the dreaded “snake bus”, i would definitely use the 1mm thick and thar would carry it reasonably well. Where these would really shine is triangle packs which are never easy to properly arrange.
0:00 1mm thick electron heaven. 0:29 the nickel strips are copper plated to decrease resistance from the cell to copper heaven. 0:39 each bus has a nickel strip to attach the balance lead to except the collectors. But i might just remove those and solder directly to the copper. 0:49 The 8mm wide copper plated nickel strip carries current both directions up to the 1mm copper heaven. So it’s like 16mm wide nickel. 0:59 the copper deckplate is supported on pedestals that get it above the plastic cell retaining triangles.
Wow thats nice 👏. I'm looking for these busbars myself. Do you think the kweld can do the 1mm thick plate, also how much time did it take from ordering to receiving? Thanks for any help you may give me.👍👍
The thickness of the copper doesn’t affect the spot welder you need. Its nickel strips laser welded to the copper, so the spot welding you meed to do is mist like spot welding 0.2 mm thick nickel. I ordered 1.0mm thick because I had a plan to use some thermal pads on the busses so it would conduct heat out of the plastic battery case, and then I was toying with the idea of using Peltier modules to subcool that because ambient temperature here has been 35c in the shade and cells last longer
@imho7250 Thank you for taking time out your day and helping me with all this very useful information I truly appreciate it and am going to implement it in my build for sure. I'm not building anything crazy. I'm just build a 5p 20s triangle pack with samsung 40T cells to feed a bafang bbshd at a max of 4000w burst. I'm calculating about 60a at 72v so I think the 0.5mm or even the 0.3mm would be adequate for the build. Do you think I can go with the 0.3 or would the 0.5 be good?
@@skonyc3164 , since its a triangle pack, and therefore impossible to get optimal cell arrangement, you might need to use 0.5mm thick. I would have to see the actual cell arrangement to find the worse series bus, and thats the one that determines the thickness needed. If you have your cell arrangements already laid out on paper or cardboard, draw in the shape of the buses that will connect all the groups and draw a line between each 5 cell brick where it connects to the next brick. Find the shortest series bus border length and then multiply this by 0.3, 0.5, and 1.0 mm to get the mm^2 for that series bus. Lets say your worse bus is only 40mm wide, and you want to send 60a through it, since thats the current bandwidth of your 5p groups. In theory AWG 12 is enough for 60a, and thats 4.0mm^2, so even 0.1mm thick copper is enough. So the 0.3mm which is minimum they make should be more than enough for your cells no matter how you arrange them, but still try to get optimal arrangement which gives the longest border length between bricks. Like my 16s5p has 100mm border length for each series connection. Thats as good as it gets. If you will use a Bluetooth BMS, you want to do your best to get the tabs for the balance leads placed where the voltage at max current will be least affected. When you give full throttle you don’t want cell differential artificially increasing. If it’s just a basic BMS it doesn’t really matter because you will never see the cell deviation under load.
@imho7250 I'm still at the planning phase of everything right now, so this is great information. I also subbed to your channel and hope you make some videos as you are a great source of knowledge. Much appreciated, and Thank you once again.
@@skonyc3164 , yes, I’m also planning and plotting my next project, thinking about making a full suspension fat bike ($300) into a pedal assist with the TSDZ2B or TSDZ8 motor kit, and then making a battery that will fit neatly and inconspicuously as possible. I want it to be a bicycle with electric assist, not an electric bike with human assist. Lol
I would rate the P42A at 20a CDR rating if starting at 30c and not allocating it to go over 60c. So that would give the 5p pack a 100a continuous rating. But in my ebike everything is built around 60a continuous, 180a for 10 seconds. And probably 100a for 2 minutes. My goal is to never let it go above 45c and try to keep it as close to 25c as possible. These buses are so thick they will make almost 0 watts of heat, so they will strictly act as heat sinks. I plan to then use silicon thermal pads to conduct heat from these busses to the plastics battery case, where the heat can get out. Much like a laptop power supply with no fan, it merely conducts the heat to the case and then dissipates it.
No such thing as too thick. Lol. But it’s thicker than needed for this perfect cell arrangement. The 0.3mm would be plenty. I got 1.0mm thick because by time you pay shipping, the extra cost for thicker is not much.
@@enekojuanenalodeiro3794 the thickness needed for that current it depends on the cell type and cell arrangement, but 1.5mm thick copper would probably work with almost any cell Type and arrangement.
Wow those busbars look really nice!
Yes, they are super nice. Unfortunately I made some mistakes building the pack and recently tore it all apart. I plan to make a video about it to show some things to be aware of when using these busses.
I burned some holes in my cells during spot welding because I was in a rush and not making sure everything was seating properly. Because these are 1mm thick copper, they are rather stiff and need extra precaution when applying the correct amount of force on the probes.
Long story short, i was using the standard method if press hard to seat the nickel on the cell, then relax pressure so it can get a nice weld. Unfortunately on some welds the nickel actually pulled away from the cell and that gap caused a lightning bolt from hell and burns a hole in the bottom of some cells.
It was a combination of careless steps on my part, getting in a rush to get done.
1. Not having proper workbench. You need a sturdy flat work surface to make sure the cell holders are fully seated. If not seated then the nickel has a hard time reaching the cell.
2. Not making sure the cell holder is fully seated. With regular nickel you can sort of get away with it because it will bend and yield easily, but these 1mm copper plates sit on top of the tiny triangles and the nickel is a U-shape which dips down to the cell. If the cell holder isn’t seated, the nickel does want to lay flat without a lot of force on the probes.
3. When it doubt, use more pressure not less pressure on the probe. A weak “dud” weld is better than a hole. Lol
4. Time your time. Take a break when needed. I let myself get in the “get ‘er done” mode instead of quality assurance mode.
5. If possible order a “test buss” with 2s2p (2x2) so you can test it with your cell holder and practice with some old cells to get the right spot welder settings.
Are you using a K-Weld spot welder? I can imagine those very stiff bus bars dont give you any play. They really look nice. Those busbars are ready for the new gen Molicel 21700 P45 and P50!
@@718og , this video shows the same welder I have. It seems to do good. I haven’t tried the copper-under-nickel with it yet to see if it has enough power for it.
These busses were overkill because i had ideal cell arrangement, so the 1mm thick copper on a 100mm wide series connection means i had 100mm^2 total, or 20mm^2 per cell, basically like using 5x AWG6 wires to make the series connection. No cell on the world needs thar much, lol.
The 0.3mm^2 would have been more than enough for a perfect arrangement, but for tricky arrangements where you want to connect bricks that are 2x3 at the 2x border, basically a 2x6 buss, now the 1mm thick starts making sense because 3 cells x 45a (135a) are going across that 20mm2 buss.
My basic rule of thumb is 1mm^2 of copper for each 10a, so the 1mm thick could connect 4cells deep on each side.
The company custom makes each set and sends you the drawing to verify. I went with simple 16s5p because my battery box fits 5x16 rectangle, and that gave me 60v which is what I wanted.
But if I wanted 72v, 20s4p, i could have run a set of 2s4p busses (2x4 shape) down one side and then come up the right side with 1x8 busses connecting the last 4 sets of 4p. For these which are essentially the dreaded “snake bus”, i would definitely use the 1mm thick and thar would carry it reasonably well.
Where these would really shine is triangle packs which are never easy to properly arrange.
0:00 1mm thick electron heaven.
0:29 the nickel strips are copper plated to decrease resistance from the cell to copper heaven.
0:39 each bus has a nickel strip to attach the balance lead to except the collectors. But i might just remove those and solder directly to the copper.
0:49 The 8mm wide copper plated nickel strip carries current both directions up to the 1mm copper heaven. So it’s like 16mm wide nickel.
0:59 the copper deckplate is supported on pedestals that get it above the plastic cell retaining triangles.
What is the depth of that nickel strip from the upper surface of the copper plate
About 2mm, enough for the 1mm thick copper plus 1mm for the raised portion of the cell holder.
Wow thats nice 👏. I'm looking for these busbars myself. Do you think the kweld can do the 1mm thick plate, also how much time did it take from ordering to receiving? Thanks for any help you may give me.👍👍
The thickness of the copper doesn’t affect the spot welder you need. Its nickel strips laser welded to the copper, so the spot welding you meed to do is mist like spot welding 0.2 mm thick nickel.
I ordered 1.0mm thick because I had a plan to use some thermal pads on the busses so it would conduct heat out of the plastic battery case, and then I was toying with the idea of using Peltier modules to subcool that because ambient temperature here has been 35c in the shade and cells last longer
@imho7250 Thank you for taking time out your day and helping me with all this very useful information I truly appreciate it and am going to implement it in my build for sure.
I'm not building anything crazy. I'm just build a 5p 20s triangle pack with samsung 40T cells to feed a bafang bbshd at a max of 4000w burst. I'm calculating about 60a at 72v so I think the 0.5mm or even the 0.3mm would be adequate for the build. Do you think I can go with the 0.3 or would the 0.5 be good?
@@skonyc3164 , since its a triangle pack, and therefore impossible to get optimal cell arrangement, you might need to use 0.5mm thick.
I would have to see the actual cell arrangement to find the worse series bus, and thats the one that determines the thickness needed.
If you have your cell arrangements already laid out on paper or cardboard, draw in the shape of the buses that will connect all the groups and draw a line between each 5 cell brick where it connects to the next brick.
Find the shortest series bus border length and then multiply this by 0.3, 0.5, and 1.0 mm to get the mm^2 for that series bus.
Lets say your worse bus is only 40mm wide, and you want to send 60a through it, since thats the current bandwidth of your 5p groups. In theory AWG 12 is enough for 60a, and thats 4.0mm^2, so even 0.1mm thick copper is enough.
So the 0.3mm which is minimum they make should be more than enough for your cells no matter how you arrange them, but still try to get optimal arrangement which gives the longest border length between bricks. Like my 16s5p has 100mm border length for each series connection. Thats as good as it gets.
If you will use a Bluetooth BMS, you want to do your best to get the tabs for the balance leads placed where the voltage at max current will be least affected. When you give full throttle you don’t want cell differential artificially increasing. If it’s just a basic BMS it doesn’t really matter because you will never see the cell deviation under load.
@imho7250 I'm still at the planning phase of everything right now, so this is great information.
I also subbed to your channel and hope you make some videos as you are a great source of knowledge.
Much appreciated, and Thank you once again.
@@skonyc3164 , yes, I’m also planning and plotting my next project, thinking about making a full suspension fat bike ($300) into a pedal assist with the TSDZ2B or TSDZ8 motor kit, and then making a battery that will fit neatly and inconspicuously as possible. I want it to be a bicycle with electric assist, not an electric bike with human assist. Lol
Nice! What would be the max continuous current of your pack?
I would rate the P42A at 20a CDR rating if starting at 30c and not allocating it to go over 60c. So that would give the 5p pack a 100a continuous rating. But in my ebike everything is built around 60a continuous, 180a for 10 seconds. And probably 100a for 2 minutes.
My goal is to never let it go above 45c and try to keep it as close to 25c as possible.
These buses are so thick they will make almost 0 watts of heat, so they will strictly act as heat sinks. I plan to then use silicon thermal pads to conduct heat from these busses to the plastics battery case, where the heat can get out. Much like a laptop power supply with no fan, it merely conducts the heat to the case and then dissipates it.
@@imho7250 may i ask where you bought them?
@imho7250 but i thought they can do 45a easily?
@@MrDeceptacon88link in the description. But every order is custom made so to get the real price for your specific pack you have to message them.
@@imho7250 ok thx..but im not good at welding
It's too thick
No such thing as too thick. Lol. But it’s thicker than needed for this perfect cell arrangement. The 0.3mm would be plenty. I got 1.0mm thick because by time you pay shipping, the extra cost for thicker is not much.
@@imho7250 I had 1.5mm copper for 250amps and 650A peak, do you think is great?
@@enekojuanenalodeiro3794 the thickness needed for that current it depends on the cell type and cell arrangement, but 1.5mm thick copper would probably work with almost any cell Type and arrangement.