Got it, just wanted a second opinion since it wasn’t clearly written, much thanks
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I think someone tried spot welding copper, one of the ebike people on endless sphere. Sorry I can’t point you in the right direction but I saw a post about it on here somewhere
They were successful but I think only at the highest weld setting or something? 0.6 mm is insanely thick though, I think they were using something thinner. You have to keep in mind too that copper is such a good conductor that it takes way more energy to successfully spot weld it. It dissapates the energy too quickly
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Hi guys new member here, i have build many ebike batteries in the past.
But today im not sure how i should do the Layout on my Enclosure. İ wanted to put in 13S5p but saw it can be a bit dangerous.So im not really sure how i should place the cells. İ want to split in to 4 or 5P packs and isolate with Epoxyd on thight places and wrap into shrinking tube.
Any suggestions welcome.IMG_20200920_142546|666x500
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So what’s the reasons to use natural cure silicon over hot glue?
I get that silicon is more flexible but personally I don’t want my p groups flexing or getting so hot the glue melts. What are the other advantages
@b264 @glyphiks I know your both go for natural cure silicon
In my experience, hot glue doesn’t stick nearly as well, and breaks off easier. Silicon is more flexible and better suited to high vibration requirements
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It stays flexible, is unaffected by heat, and is a great insulator.
The only disadvantage is it takes a while to cure, unlike HMA (hot glue) which cools in mere seconds. I feel like NC silicone has every other advantage besides that. Someone help me if I missed something.
If you are a factory running an assembly line of battery production, I would not even consider silicone.
If you’re a home builder making a battery for yourself, I would definitely use silicone.
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It highly depends on the glue, there are some HMAs with a lot more flex to them. The black stuff I use doesn’t come off so it’s great
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FLEXIBILITY With in a p group flex is bad as the flex will put stress on the nickle
HEAT hot glue is set up to 50degC has creep under load between 60-80 melts over 80. Q30 should be keeped under 60degC. If your running you battery’s so hot thay melt the glue you got bigger issues IMO but a little to close to the limits. High melt temp would easily stop this
INSULATOR I only used hotglue between the neg of cells in the same p group so 0v potency differs.
HMA 2 manger weaknesses are susceptible to direct sunlight and water but I hope the inside of a battery would never see them
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The vibration point still stands, and the silicon generally sticks better. The flex is not enough to overcome the nickel
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I’m surprised by that as personally from experience I’d say the opasit this could be because i used industrial stuff (acquired from work) in HMA and silicon has been DIY off amazon maybe I need to try other silicons
Idk the silicon I have used sticks really well, whereas my HMA sometimes just falls off the cells
HMA distorts or rips the heat shrink. Silicon I can get off in chunks then rub a thum up and down to clear the remains off.
Hobby stuff is often low melt to avoid burns that migh fall off
I have a high melt type, I have the Gorilla brand hma and a high temp gun, it will burn you lol ask me how I know
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Temperature affects hot glue as well, the hotter it is the better it sticks from my experience
I have low melt HMA and a super hot glue gun, so it seeps into the gap between cells and spreads out really well, plus it self levels. The shrink wrap rips before I can yank the cells apart
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Use alcohol / acetone to get the glue to unstick super easily 
That has saved me a LOT of time replacing the shrinkwrap on cells haha
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I just don’t make mistakes 
JK I do but not with hot glue yet lol
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Hope this isn’t out of place to ask here. I’m in Canada and have found a local battery builder who came at high recommendation from an owner of a makerspace that I’m friends with. I’ve had a couple consultations with him about what I want in a battery and he has come back with a recommendation to use the LG hg2 cells. In my research in this forum they get mentioned a bit but seem they are not super common. On paper they look pretty good, other than the high instances of fake ones floating around. He normally builds for scooters, bikes, robots etc and isn’t super familiar with eskate stuff. Before I commit the cell type, I thought I’d make a post about here before I make a final decision. Board build specs. Going for a on-road, light off-road hybrid using a mbs mountain board base, 7 ior 8 inch wheels, top deck battery box, 15-72 tooth ratio, 190kv 6380 TB motors controlled with a Stormcore 60d. looking for range as a priority, its mostly flat around here but there are periodic 30-40% grade hills that I have climb regularly. I’m 200 lbs, setting up for a max speed of around 50km, enjoy crisp acceleration. Canada cell prices are pretty wack but the 30q, hg2, and the vtc6 are pretty much equal in price, 40t’s are slightly more and I’m already a fan of them as I use them in my other board. So any thoughts? Considering what I’m building is the hg2 a good fit? Would something fit better. Any suggestions super appreciated.
As with any cell, the number of cells in parallel is going to dictate what you can get out of your pack. I have never used them, but from what I have heard, the HG2’s are very similar in characteristics to the 30Q’s. What size of battery are you looking to make?
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HG2s are pretty similar in performance to 30Q cells. They sag a hair more at a given current and state of charge, but generate less heat internally. Their cycle life is close too, with the 30Q winning out by a little bit.
The VTC6 performs even better than the 30Q, but I don’t have any cycle life data on those at high currents. I’d expect them to be pretty close to the other two (~200-250 cycles at 4A charge/20A discharge before they reach 70% capacity).
On those merits alone, if the cost isn’t significantly different I’d say go VTC6, with 30Q and HG2 being second and third choices respectively.
It’s harder to compare those three 18650s with the 40T and other 20700/21700 cells on an apples-to-apples basis because the size/weight/volume/capacity differences between the two.
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