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For a big pack with a high P count you will stay well within a region that is acceptable for the cell.
Off-Road boards usually do not go fast in average and there for the amp drain is not as high as many people think. A10P pack can deliver 70-100A continuos with such a cell. In reality you will never see 70A continuos form your battery.
If you have fixed budget for the battery and you want a lot of range, you can go higher in P count and get what you are looking for. Cell prices for higher drain cells can be twice as high as for lower drain cells. So far the same money you can build a bigger pack and reduce the strain from each cell.
At the moment some cells are also hard to buy and that also plays a role.
Some riders also ride on flat terrain and others ride in hilly areas. Some riders are 70KG other 100Kg.
Conclusion: You can not simply judge a cell without knowing the pack size and terrain and rider weight + average speed.
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While you are completely right about the intended mountainboard use of the board and battery box, i want to say that my board on street is capped at 110 battery amps total and i can really feel when i hit that duty cycle limit where motors start to throttle.
With 12s4p P42A cells at room temperature, they sag down to around 26% on the wand so i assume around 3.3V/cell at 27A load each. Mooch test says 3.55v at 30A so everything else is cable losses and/or measuring errors
If i were to use the battery box with 48G cells in 12s7p i would actually get a similar or worse sag trying to pull over 100 battery amps from it even though it has 3 more cells in parallel. Add the fact that i’m draining 16A from roughly 8A rated cells and things don’t look nice anymore.
Battery box and pcb look nice, p42a’s fit with a bit of sanding, everything is cool, it’s just that some around here guzzle electrons like a hellcat does petrol on a german highway. They WILL take offense if they are told a fiat micra engine is all they ever need
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The Samsung 48G you recommend though is typically more expensive than the much better performing 21700 cells. The 48G is also much harder to find.
By using a better performing cell you can save money and possibly have a smaller pack (fewer cells in parallel) too.
I disagree, relative cell performance is independent of those things.
How the Samsung 48G performs compared to another cell like the Samsung 50G or Molicel P42A (if it fits) doesn’t depend on pack size, terrain, rider weight, average speed, etc.
The performance of any particular pack when riding, of course, depends on all those things and more. We can’t even begin to estimate how a pack will perform without knowing a lot about how the pack will be used.
But we can certainly judge (via testing) how a cell performs, and compares to other cells, without knowing any of those things.
Respectfully, with the Samsung 48G performing worse than most other high and ultra-high capacity 21700’s, being harder to find, and typically costing the same or more than the best performing 21700’s I feel it becomes difficult to build a case for its use.
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If someone takes offence from a sentence like " dare a look at a certain cell", I feel very sorry for that person. Posting toxic comments also doesn’t help… coming up with a viable technical argument does help.
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Cant let it lie can you? I already provided you with a technician answer but here it is again with pretty pictures and telemetry.
In this post is a telemetry log of a ride I did late last year, switch it to satellite. Entirely off road.
Now lets only concentrate on the battery current, as you can see multiple times the battery current is higher than the maximum current your 12S7P 48G pack could supply. As @Battery_Mooch says, those cells are good for max 5-7A per cell, so circa 35A total current output. My board is set for 80A per side battery max and is geared for ~30mph max speed, so potentially on bad terrain at 50% duty cycle my battery can be approximately 90A total output current and just 15 mph - this is already almost 3x the power output that your 48G pack can provide. If you gear shorter, the situation gets even worse.
Your 48G pack will be severely power limited, we all know how motor amps work against battery amps, I’m not disputing it will still have torque off the line, but as you accelerate on bad terrain the battery will sag, the internal resistance will climb, it will get hot, it will be an awful experience to ride and the cells will suffer a short life. Can you honestly hand on heart say you have tested this before recommending, because I don’t think you have - and that’s my issue. I know you have never been wrong in your entire life, but I’m sure you can see why I think you do this community a disservice with shitty advice.
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With regards to battery amps here’s my log from riding that location.
Consider that this is on a board with a 18s4p pack. The point of interest is this:
So over 9 miles and an hour long ride I drew peak power of up to 16A per cell. But more interesting is that the average current is 4.3A per cell for an hour.
Curious as to @Battery_Mooch and @Trampa opinions on how 48G would cope delivering over 4A continuous for over an hour with peaks up to 16A?
Im guessing they would be a saggy mess and I would have spent an hour sitting on the battery voltage limit. I can verify that the P42A would give no fucks.
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Out of curiosity. I see your average Wh/km was 52.3
What tyres and gearing were u using?
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Yeah that’s 84.6 wh/mi. Impressive right. That’s more than @Trampa said was even possible on a board.
I’m running maytech 63100 on 5:1 gear drive with 8" tyres. Also max motor current in this log is only 65A per motor which suggests that I had my board in its low power profile for this ride 
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and I managed 50wh/km too so 80wh/mi on 8inch tyres and 1:5 gearing. We ride our boards hard enough off road and record every ride for analysis. Can you imagine that 48G pack on 1:6 gearing? would be absolutely awful
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I’ve ditched that cell idea long time ago. Will be using p42 molicell pack that you guys will make for me I’m just trying to figure out my range with that pack.
I’ll be on 4wd 5:1 gearing with 9"
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can we just use metric 
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4A continuous is a great operation level for the 48G. Other cells can run at slightly higher voltage levels and for a bit longer though.
Average and true continuous current draw can be two very, very different things though!
Pulsing a 48G to 16A will result in huge voltage sag versus other better performing cells. Depending on the charge level and your BMS settings that sag could result in the BMS throttling down or other unwanted actions.
Does this make a 48G pack useless? No.
It’s just that there are better cell choices IMO if considering what to use (or buy) for a new pack.
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I am pretty sure anybody reading this thread don’t need Trampa to admit being wrong to get to the same decision as you.
People like Lee, Q and Mooch are testing stuff and providing good advice for those of us who can’t afford making mistake on expensive and potentially dangerous gear such as batteries. Thanks for looking out for us guys.
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How do we calculate true continuous? I can get XML data for that log and would be curious to smash out a script that can calculate these sorts of numbers if there’s a simple way to calculate
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There are some on esk8 news
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You might be able to calculate the average over a time period but that average number wouldn’t be the same as operating at the same level continuously.
Let’s compare 4A true continuous versus 16A pulsed at a 25% duty cycle. Both of those take the same amount of charge out of the cells when averaged over time but the 16A pulses result in a lot more voltage sag (when being pulsed) and will result in throttling down of the power or other bad things earlier than if operating at a true 4A continuous discharge level.
You could have a wide range of pulse current levels and duty cycles, all averaging out to 4A, but each would result in a different total ride time due to the different levels of voltage sag during the pulses.
You might be able to set the BMS to ignore the sag, by using longer time settings for when the BMS reacts to a low cell/pack voltage, but that isn’t a feature on all BMS’.
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Back to the topic with another question.
Comparing 4wd with 2wd does the combined wh/km stays about the same or should I expect noticeable increase in total consumption?
Also i guess current is not divided 50/50 to front/back wheels as it is more likely for front to free spin…
Generally a 4wd system has more drag and mechanical losses in the system so it will use slightly more wh to cover the same distance.
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In my limited experience you loose 25% range when you add another set of drives.
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