But motor amps don’t equal battery amps. Usually you will pull big motor amps at a low speed and duty cycle so the battery amps will be alot lower.
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Overall I think the 40T pack would sag less near max discharge. Giving you 200A battery @ 25A per cell. Here is a comparison of 30Q and 40T at 15A/30A. You see the voltage drop on the 40T is about the same at 30A as 30Q Is at 15A. This leads me to believe that the 40T pack at 200A discharge you will still have less sag than the 30Q pack at 180A discharge.
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Right, that’s why I posted the battery A too.
@KfromtheBay very interesting Kenny! That’s exactly what I want to check. ATM we have a V sag of 1-3V on full throttle on straight streets. On inclines I can imagine that it’s even more. So I’m curious which one will make the race. My money is also on the 40T our technician bets on the 30Q. So we will see soon 
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Yes I did, I have 2 kcaps in parralel so i can weld as fast as a maniac lol
The welding amps are around 1600 with the standard cables and electrodes
Only the cables get hot, capacitors, and their power supply is at most 20-25c with fast 65J welding
Actually i didn’t have to try that hard to blew up my first lipo, I have had the best experience with 3s 4ah red graphene ones, as they provide enough current and are a little harder to blow than the 5ah ones
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Here we go. Hopped Spotwelder train. I have to learn it.
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The 40T 8p pack will be 1lb lighter.
I think your decision should rely more around which will perform best through its capacity range. I have no idea what to expect, but it really depends on your amp draw. But the 40T may sag more than the 30q
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Question for the battery wizards, I have one of those TB12s4p batteries and I am noticing that the pack does at around 35 volts and the indicator on the pack says 30% when I go to plug it in and charge it…anyone know what could be happening? Or what I can look at to fix this?
Picture would be good.
Best guess is that the battery meter is incorrect. Those things are cheap.
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Gotcha, I will post a pic when I open the enclosure, but you cant see much cause it’s in some sort of hard case. But I will tell you this, my range is like 10ish miles and that’s a bit low for a 30q 12s4p pack even on pneumatics
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Make sure you don’t keep it on the charger if it’s a broken p group, that’ll do lasting damage to it if it manages to charge 11s to 50.4v
Have you checked cutoff voltage on esc?
Oh! Good to know. I will open it up and try to see what’s up
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I have it set to 3.00 via my metr app.
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I missred first post. Thought it was 10s for some reason. Definitely crack that baby open
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Will crack and post tonight!
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Whats the fastest way to get nickel? I realized I’m trying to build 4 batteries over winter break (10s4p 13Q, 12s4p 30Q, 10s1p 40T, 10s2p 30Q) and I have nowhere enough nickel for it…help. Is the stuff on Amazon any good?
Same for insulation rings actually
Also whats the cross-section recommended for a given current? I know there’s a chart for it somewhere but I can’t find it anymore
(I’m not prepared for this)
$5 Samsung 40T until the 27th.
$3 Samsung 25R until the 25th.
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I’ve had luck on amazon. But the listing says it’s currently unavailable with no estimate of restock. Best bet would be reading through reviews to see if they and the product is believable. Give a good scrape and brine bath before using just in case
I guess make sure I pick on that accepts returns?
Also recommendations for the nickel type? I’ve got a cheap Sunko so I suppose 0.2x15 is probably the biggest I can have?
Yeah that’s the way to go to protect yourself. I could’ve sworn I read that things can get hairy with the sunkko over .15mm thickness. Personally, I use the Maletrics with a high discharge lipo and it takes 0.2mm with ease
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