I use a blue flame on my torch, no waiting
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⏠18,87 53ďź
Off | High quality 220V Portable BGA Rework soldering station Hot Air Blower Heat Gun 8858 Better Hand-held hot air gun 6pcs nozzle
https://s.click.aliexpress.com/e/sb0RlXbUP
I got this for heat shrinks. You might even be able to do some smd soldering with it but I havenât yet.
It heats up really fast like seconds and has adjustable fan speed en heat speed via buttons. Not sure what the minimum and maximum temperature is.
What gauge wire should I use from the negative terminal to B- on the BMS when bypassing the it? My pack can put out 40 amps
I only have 22 awg on hand, will that work?
Hmm that is really small for charging. Maybe just run 3 wires to b-
I will just charge with 2 amps, but I might buy some 18 awg just incase
22 AWG should be good for up to 7A. Best not to push it though. For 2A it should be OK. If you plan to upgrade the charger in the future you would be better off getting at least 20 AWG.
Cover your eyes. I have made something truly disgusting
Maybe I should not be tipsy while doing my next battery
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Well, I will be rebuilding this abomination into something more well built.
I was thinking of replicating this design, but I do not understand it at all.
It seems that the balance wires go onto the negative side of each cell group, can I make it like that with this type of BMS?
Also I do not really understand where the series connection connecting the two 5s4p packs is. I assume it is at the end, where the fish paper is connecting the last cell group positive to the negative cell group that is to the left, like so:
But isnt the positive main lead supposed to be at the last positive cell group of the pack and the negative on the first cell group of the pack?
If someone could clarify, I would be very grateful. Maybe even the one who made the pack, Frederic @EboardSolutions
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Hey guys, I plan to build my first battery pack â 12s2p Samsung 40T. Iâll have the parallel pairs welded by a friend because I donât have a spot welder. Iâll do everything else myself though. I got 0.2/25mm nickel strip from nkon and Iâd like to use it like this for both connecting the parallel pairs and for doing series connections by soldering 10AWG wire on the small surface at the top:
Does that sound like a good plan?
Alternatively, I could cut the 25mm strip into 2x 12.5mm and get those welded on rotated by 90 degrees:
That way I would get more surface for soldering but it would require more welds for doing the parallel connection. That sounds like more work. Would that be the better option nonetheless?
This will be for a street board and I assume average discharge will be around 10A with occasional 40-50A bursts.
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both cases would need the same amount of welds in my opinion. just because it´s one piece in the first picture i non the less would do 3x2 welds per cell. anyway it´s not that much more work to do some extra welds, wouldn´t worry about that.
ok, maybe i got it not right⌠the second version would be be the two strips to the cell and one strip than for the parallel connection like TT this? if yes, than yes that would be more work to do so, but why not just to take away a bit more isolation from your silicon wire and soder to both taps in this case?
i think both ways should work well.
just make sure you add some fischpaper between nickel and the cell surface. especially also on the positive side around the corner from the cell surface to the tap.
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Anyone willing or know of anyone who can build me a battery pack? Im in Toronto, Canada and need a 10s6p stacked pack from Samsung 30T cells. I can either provide or pay for the cells and also provide a DieBieMS to connect it to.
Thanks!
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A few years ago I did the training to ship lithium batteries. To do it properly and legally you have a quite a few hoops to jump through. To ship a prototype battery pack, well, you wont want to be doing that often as they are expensive to ship and the regulations for packing a prototype battery pack increase the cost significantly. You also need to go through the training yourself or hire a company to package the goods for you.
The shipping costs increase because every person who handles/transports that shipment must be fully DG trained. That includes the driver who collects, the person who unloads the vehicle etc etc. Then the paperwork, URGH, so much paperwork, labels, forms, dangerous goods contracts.
The company I work for wanted to ship 4 lithium cells @ 4Wh each from the UK to Poland as UN3480 (Cells by themselves). Cost was ÂŁ582 with UPS on a 4 days by road service. Attaching the cells to the RAID controllers made the shipment a UN3481 (cells were packed in equipment), cost was ÂŁ49 & delivered next day.
UN3480 are fully regulated dangerous goods and you must have a contract with the carrier.
Prototype batteries, you can easy double the cost just to ship, not including packaging.
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wow youre a rare resource. what do you think of what seems a norm of uncertified batteries being shipped in the diy electric skate community?
I would not do it as whoever who packs and ships the package is personally liable. You do not want to be liable when a $400 million aircraft falls out of the sky or when a lorry goes up in smoke.
They are dangerous good for a reason and shipping un-certified packs is just not allowed (even if they are under 100Wh). ATM carriers are too busy to check every lithium battery shipment for certification so they take it on good faith that people are following the rules. At the same time they also know that maybe 70% are actually following the rules but if they had to check every shipment then nothing would move. This is why the shipper/packer is liable. If they become suspicious or do a random check and then ask for the certificate you are pretty screwed without it. We are talking about the possibility of fines and/or prison time at worst. They will also go over your entire shipping history and get you for your previous shipments.
At the moment we get away with it and I think most people will get away with it for years to come but one massive fire and regulations will change over night. There are serious risks that need to be taken into account.
Please note that Iâm generalising things here as the requirments change depending on many factors from Wh, number of cells, number of packs, if they are shipping alone, packed in equipment, packed with equipement, weight etc etc.
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Iâm planning on building a 10s4p and asked LiTechPower to provide a certain BMS for me. They have it listed on their site now: https://litechpower.com/product-detail/HCX-D725LI10S15A.html
Any reason this BMS would be deal-breaker? I like the form factor and high balance current. Itâs like the D503V1 but it actually balances. I will be using it as charge only.
I see it doesnât âautomatically recoverâ but is âcharge to recoverâ but that shouldnât affect me because it will be charge only, right? Thank you!
EDIT: Litech contacted me stating that it doesnât balance and allowed me to cancel my order.
At least your balance wires are not crossing over each other 
DHL offers shipping âprototypeâ or diy batteries, the only requierment is that they need to be sent to a company that will package them and prepare for shipping that costs if I remember well 100eur, after they are packaged that way they probably give out some certificate and it should be able to go on a commercial plane
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How much space do you need between cells welded end to end? And can I fit 4x 21700 cells head to tail in a 290mm slot?
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