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Sometimes I cut corner and give the problem to the futur me 
selfish with myself
selfish with myself
GOOD NEWS FOR THE WB E-TURBO
- Thread starter WB projects
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Hey guys! A lot of work done today with the battery pack! Each bus bar clamp 2 lead of 2 batterys that I bend like in the 3rd picture. The small screw in the middle is for the BMS ! Tu top is insulate with an other plate tu put the ESC
Nice! Is that acrylic or polycarbonate? I can't wait to see the finished pack - working with pouch cells seems to be challenging; seeing what you have in mind will be interesting. The one thing I've noticed with OEM-type pouch cell batteries is they clamp them together really tightly - perhaps to keep them from puffing up? Though I would think that could cause localized heat issues. I didn't clamp my LiFePo4 car batter cells together, but spaced them out so there's airflow between the cells. Though with these things we don't see the same run times as an EV would.
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Thats polycarbonate left over from an old job we had at work! I space them with a 2mm gap for air flow! I think Its a good and easy way to clamp the leads together! Im proud of it 
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I just watched it too - that really is a brilliant design for pouch cells. I also had a thought about your BMS - if the BMS can't handle the current, you could have the BMS main power leads just switch a contactor - like the kind I'm using (which is supposedly a for a Tesla):
Don't buy the ones labeled "made in china" - those are probably counterfeit. I think I paid around $60 USD for mine. If you want to go that route that is. The nice thing is you can use it as a safety for the system, too. But you could also just try the BMS. That might work ok.
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Don't buy the ones labeled "made in china" - those are probably counterfeit. I think I paid around $60 USD for mine. If you want to go that route that is. The nice thing is you can use it as a safety for the system, too. But you could also just try the BMS. That might work ok.
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The BMS is a one way, so the current don't go out by the BMS. I use it like a charger on my other set up and it work fine! The 2 way BMS is so much expensive and they almost not handel the 400a. The relay is a verry good idea! Thanks I will keep that in mind
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they were clost enough with 0.04v to plug them! Verry stressful. Every bus bar added is more and more dangerous I droped the allen key and my heart stoped thats why I have a top plate
Lol - I know how you feel. When I was tightening the busbars in my packs, I had a moment where I realized what would happen if I dropped the wrench. I immediately went and covered the wrench with tape so it couldn't short anything out...
I like your solution for pouch cells - it's less "janky" than even a lot of commercial packs. Are you still planning on making an outer box for the whole thing? That would give you another level of safety and the pack more structure.
I like your solution for pouch cells - it's less "janky" than even a lot of commercial packs. Are you still planning on making an outer box for the whole thing? That would give you another level of safety and the pack more structure.
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Hahaha I scream like a girl when I droped it but, deep in my heart, I love danger and I was curious what would happen if I drop it
Yes im planning to do a outer case
Yes im planning to do a outer case
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Probably stainless
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Hahah yes there's a high chance I made it in stainless 
The clamping systeme was clear in my head but the bottom plate and the studs come after! It turn out way better than I first tought! When all the clamp is screw, the batterys don't move a bit!
The clamping systeme was clear in my head but the bottom plate and the studs come after! It turn out way better than I first tought! When all the clamp is screw, the batterys don't move a bit!
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Loocking my battery, I had a new idea. The only thing I'm worryed is the "air flow" I don't think they are going to be hot, not even worm, BUT I not sure at all. If I put them in a box, yes this is safe for fire or something but I have not air flow. If I cut channel for air flow, they not safe for fire.. anyway Lifepo4 don't burn. Anyway I may need your idea and all
Thanks all
Thanks all
I just watched that - and mounting the ESC on top is ideal. No voltage drop issues or anything to worry about. The stainless sheet on the outside welded to the spacers is a good idea too. I wouldn't worry too much about heat. One thing I discovered when I was running LiPos (and LiFePo4 is similar), as they warmed up, they performed better. Check out the temp map for your cells:
Looks like optimal for your cells is around 35* C. Unfortunately, running them cooler makes them last longer, so there's that to consider:
But 35* C is still good cycle life. Maybe put a small temp sensor inside the box and see how they behave - but I think they'll be fine. If you're really worried about heat between cells, you could put in 2mm thick almuminum plates in between the cells, and instead of stainless outside, you could have aluminum, with the plates touching the outside walls (maybe bend tabs on the ends for better heat transfer). But again, I'm not sure it'll be necessary.
Looks like optimal for your cells is around 35* C. Unfortunately, running them cooler makes them last longer, so there's that to consider:
But 35* C is still good cycle life. Maybe put a small temp sensor inside the box and see how they behave - but I think they'll be fine. If you're really worried about heat between cells, you could put in 2mm thick almuminum plates in between the cells, and instead of stainless outside, you could have aluminum, with the plates touching the outside walls (maybe bend tabs on the ends for better heat transfer). But again, I'm not sure it'll be necessary.
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I saw 6-7psi on 49v (60v full)
last year I was at 4 psi with my old batterys
Can't wait to see it full charge
last year I was at 4 psi with my old batterys
Can't wait to see it full charge
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BTW, the voltage drop is 5.5v
Awesome! Keep an eye on your air/fuel. At 6-7 psi, you're still probably ok in short bursts at 12:1 on regular pump gas; but you really should start retarding the timing. You don't want to lose a piston. Do you have a way to pull timing? Alternatively, if your car is "flex fuel," running E85 will give you a bigger tuning window. Congrats!