with one layer? right.
still, should i use two layers? seems like a lot of soldering with one layer, lots of heat going into the cells in the process. i dont know which is better
Still,pretty good insight, thanks
if i weld another layer to it now i could do the soldering beforehand (blob of solder to the nickel before the weld) less heat going into the cells
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Co-sign w @Flyboy. More soldering yes but youâd be soldering thinner wires which is a much better plan considering where youâre alrady at as it will dump much less heat into the cells than say 1x 12 awg. Iâd opt for 18awg if youâre going to use 4 which is rate for roughly the same amperage as a 12awg.
Stacking nickel should be avoided where possible. Using multiple smaller gauge wires is a better plan.
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Directly against the cells in the middle of the pack, these are the ones that will probably get the warmest. Wedge the sensor firmly against two cells (halfway up the cells) and make sure it doesnât move while you goop/glue it in place.
After the goop/glue cures then tape the sensors down firmly. The key is to maximize the thermal contact between the sensors and the cells. These sensors, âthermistorsâ, react very slowly and have verrry little contact with the cells. This leads to low temp readings.
When we mount the sensors we need to do everything we can to help any heat reach the sensors. This makes for the most accurate readings.
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18 awg is too small in my opinion, are you sure about that? it can carry 24 amps and in theory to match what the nickel can handle its should take around 34A.
wouldnt 16awg or 14awg be better?
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Thereâs 4 of them tho. Thatâs 100 amps continuous. Itâs plenty of current capability. Again, you need to always be aware of continuous ratings vs peak. For short periods, they can handle double that current.
Each single strip of 8x0.15mm nickel is rated for 11A continuous and 22A burst
Each 18awg wire is rated for 16/32
Each P42A is good for probably 20/40 or so
Thatâs pretty conservative. Theyâll run close to 25 amps continuous. Letâs call it 22 amps. If youâre main terminals are 12awg, 4 x 18awg is sufficient 
Definitely can be done, but I feel like system ampacity limits isnât where we should be pushing it
I guess it depends on ride style, you can push 1400A through an XT90 for 3ms every minute 
Do you use 10 awg for all of your main terminals? I def donât for street boards. It then follows that 2 x 14awg, 3 x 16awg or 4 x 18 awg are sufficient and will carry more current than the 12awg. Donât see the problem here. Itâs pretty straightforward imo
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Absolutely. But for unless OP is building Mountainboard he doesnât need larger gauges unless he rides like a fucking maniac⌠which I suppose is also a possibility 
@mhunor what say you, Sir? Do you ride like youâre tempting death just to feel alive? If so, upgrade your wires lmfao
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My stealth hub 2x 16awg series and 1x 12awg termination, the off road is 1x 30x0.2 brick and 1x 10awg
Never pulled more than 30a and 80a battery side respectively
Ya thatâs what I mean. Itâs fucking hard to pull even 80 amps continuously.
Iâm am seeing some of your points. For example, the bypassed BMS in most cases means weâre only getting the charging protections so I see where youâre getting some of your feelings from. i see that point.
I think youâre undervaluing charging protections, so Iâd ask you to consider it more.
as @TheBoardGarage explained in detail a bad cell can cause others in the pack to over volt. the charger canât prevent that. The BMS at charge time can.
As @Battery_Mooch points out. the charger can also go faulty. a BMS watching for cell overvoltage as backup can prevent that.
you wonât notice a pgroup going bad riding. unless maybe youâve been through it many times.
overcharging a cell can lead to fires.
consider an external charge only BMS, if youâre really pressed for space.
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my 18awg get warm at 13a. im not sure they can do 25a contâŚ
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warm is to be expected. The ampacity values we use assume a very significant temperature rise over ambient - itâs why we use silicone wire, which is typically rated to 200 or 250 degrees celsius. You wouldnât want to hold onto a wire that hot, but it would do it with no ill effects to the conductor or insulation of the wire itself.
In the above chart, you can see that a 16 AWG insulated wire in free air will reach 100 degrees over ambient at 30 amps.
You obviously have to remember this when designing your enclosure etc, because you wouldnât want to rely on hot glue to hold these wires in place, they would melt themselves loose in short order.
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I do ride like a ducking maniac, full throttle where possible. Of course I donât want to push the cells to the max but still, speed is good.
Also, at the end terminals how would you connect the thicker wire to the groups? Hope thatâs Clear
Right, but whit my last pack Iâve seen peeks like 120amps for a little 3p 30q pack. I just simply want to bulletproof it. I have a lot of money in this build I donât want to see it end up in flames