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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I can second that. Expect 25-35% less range with 4WD vs 2WD.
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1WD king of range
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Especially if you can push assist from time to time 
I remember the good old days on a boosted…
Never thought I could get 16km range out of the 99Wh battery pack
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for a 4wd imo you should double all electronic components. 4motors 4escs and double the battery pack size of a 2wd board. but it can get a lil heavy
Well that’s the plan
Where do you get such info from? You can even waste 100Wh/km if you like. Question is: is that desirable? In the end we want to build efficient boards that consume 25 to 35 Wh/km.
Consumption also depends on rider, ride style, terrain, weather, gearing wheel size etc.
Luckily we can easily build different boards with different cells and different gearing and then see how it all impacts the efficiency. There was a reason why Benjamin coded the software in a way to show you all the stats.
If you would tweak all parameters on your board and would use a bigger pack, the cells would see even less strain, probably below 10A peak and about 3A average.
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Why is this the magic number and not “as close to zero as possible”?
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Probably just being realistic about what pneumatic wheels can do
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We must have logged a couple hundreds rides… That is the realistic number for off road boards.
You can also do some maths and use a certain efficiency number, wind resistance, friction values and other parameters. Then you can calculate were you would end in average consumption.
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I get 20 Wh/km on a regular basis on my 5:1 9" tire but in general I’m implying systems can always be improved, things can always be lighter. Just seemed like a weirdly specific range to throw out.
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