I was asking about the power source, I have a Kweld.
Oh I see you need a Kweld to actually see how it would work on it.
Have at it!
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Iād love to figure out a way to water cool these cells for far longer life
I always thought on inventing a āSubmarineā, a cooling system to cover the Lipos and take aways the heat. Like some sort of gel in a plastic cover surrounding the battery. Like a sleeve that you put around the battery. Pretty simple putting it on and the gel will take away the heat from the battery out the enclosure to some sort of radiator or aluminum plate in which the heat will transfer out by wind cooling it down.
Well, Iām not an engineer, and the gel is just a thought, but it could be anything else , water, oil, antifreeze, etc. The important aspect is the idea of the āSubmarineā or covering sleeve for the battery in order to take the heat out. The āSubmarineā will be similar (in concept, not form) to these type of gel masks or gel bagsā¦
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To solve this problem, I present to you aluminum microchannel tube: https://www.hydro.com/en/products-and-services/precision-tubes/micro-channel-tubes/
This stuff is used in the Model Y (and I assume Model 3) between cells for cooling. Coolant is sent through each end of the battery, with these channels running the length of the pack. When I eventually get some of the SPIM08s, I will be testing the use of this microchannel for a cooling method. I wonāt encase the cells in epoxy like Tesla does, but will try and keep the pack fairly compact still
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Thatās another way to do it 
. What I was thinking is a bit different. More like a plastic sleeve with refrigerant inside, gel or something else, to take away the heat.
Why plastic? Because it will be kind of flexible and could be ajusted to different battery sizes, letās say 12s4p to 12s7p lenghts or from single to double stacks or even triple stacks. Sort of a universal type of gel refrigerant sleeve for using on long rectangular Esk8 batteries, similar in shape to what wide plastic shrink wrap for different battery sizes are. This one will also be for long battery sizes. This makes any sense?
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Most cost and size effective is using Aluminium fins between the cells which then connect to a cooling block that either has mass or is air/water cooled.
(A bit similar like DRAM cooling blocks.)
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But do these cells really get so hot?
Instead of adding weight and volume with a cooling system, you could just add 50% more capacity and it would equally solve the issue.
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i still think that plumbing the whole tub of cells (recirculating oil to a radiator outside the tub) might be easier, cheaper, and lighter than using water cooled heatsinks
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Mineral oil ESK8
I like it.
If you add water to the mix, you can switch to a steam powered esk8 after the pack drains.
In seriousness though, if you could live with/deal with the weeping wicking mess, the convective surface area would be unbeatable
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soo where are folks getting the bus bars for these babies
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Dual 8s packs 480wh on these pouch packs. Will have data logger on duty.
For short track and hill racing, super fast charging.
Used Pop rivetes and plates #8 wire. On the charger, will be testing tomorrow.
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For whatever reason, using these cells in my eMTB doesnāt give me peace of mind. Maybe itās just my inability to assemble them adequately.
Just wondering, does anyone have experience with these lipos from hobbyking? https://hobbyking.com/en_us/turnigy-graphene-professional-8000mah-6s-15c-lipo-pack-w-xt90.html?countrycode=US&gclsrc=aw.ds&&gclid=EAIaIQobChMI_t3_n5LC6QIVIRh9Ch0KsgkBEAQYAiABEgKBsPD_BwE
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Iāve heard good things about them, they can take more charge cycles and run closer to their marked ratings than the normal batteries. Seen several people use them in emtb jumpers and stuff
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How are you planning on connecting them?
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Iām thinking either bus bars like @Silverline, or foil clips like @Arzamenable. I like the bus bars for the high current properties, but they seem like they might be kind of heavy, and Iām not even sure where to get them or how much they might cost. The foil clips look much cheaper and pretty easy to use oh, so I might just go that route. I just want to be able to disassemble the packs easily if I want to reconfigure them or if I have to call a bad cell group out. These things are really interesting though. Never seen batteries like this before.
2 kWh+ right there. For $165 shipped. Noice! 
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it starts to add up in cost pretty quick with the foil crimps, other method are much cheaper at scale but might require more time and effort.
@silverline how much did the busbars cost you for the 20S2P?
if someone could mass produce them that would be sweeeeeeeet
Foil Crimps
pros:
-easy
-limited tools needed, simple soldering.
-fairly good current handeling
cons:
-might cost more than other things. free shipping doe
-takes a good amount of effort, buts gets much easier once you get deeper into the box.
Busbars
pros:
easy
takes up less space
high current
cons:
not everyone can/wants to make them and source hardware. No solid guide to make them.
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I always forget, what can you charge these at? Like for 1p what can I charge it all at?
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Specs:
Max Charge Rate 120A
fastttt
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Wow, has anyone found a charger that can charge that fast? What do you think a healthy charge rate would be for these?
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