Hello im a pretty good skater. Im old though. So I dont want to kick any more. Im building my first board. I want to do a 4wd Direct Drive setup from Torque. But im looking at battery options an I think im screwed. Those DD from Torque boards can use 80amps per motor. What im understanding is that if I want to take full advantage of those 4 DD I would need a battery that can put 320amps. No I know that would be at full speed. But that would need a crazy big battery. I wanted to go 4wd for the torque an hill climbing ability. But no battery can do 320amps right? Should I just do a 2wd DD set up? Will I have loose the torque that I want? Is this 4wd DD setup just too much for the battery options available? Have any body used those DD from Torque Boards? Thanks dudes!
Greetings old man (@PhillyBoy). I’m in my first build as well for the same reasons - too old to push around town anymore - too many shoulder/knee injuries from stupid crap I involved myself in over the years. I went a simpler route to start with one DD (72kv motors), a 10s4p, and a hobbywing dual ESC. I don’t have the torque/speed need you have and where I live is totally flat - no hills. I went MBoards for everything. All the parts have arrived. Starting the assembly but I have other house projects to complete as well. Good luck!
@Phillyboy The motors won’t always be pulling 80amps actually. That might be the maximum rating, but its not what happens during real-world use. So that’s not how you need to think about your power system.
I assume you will be running a vesc based motor controller, which really is the only viable choice for a DIY build like this. For 4WD running TWIN dual motor controllers together is probably your best option.
check here for more 4wd inspirations: https://electric-skateboard.builders/search?q=4wd
When you are setting up a VESC based motor controller you can program the maximum current per motor & also max battery current.
In your case, you might have the motor current set to a maximum of 80A each. But you could actually set the max current from your battery to max 80a and get great performance.
The motor current is determined by the load on the motor, when you are at a standstill and trying to accelerate faster & faster, the load starts high, however, as your speed increases the load & current is also lower until you introduce additional factors like wind resistance or the flat road becomes an incline etc.
Also, it’s worth pointing with 4x Motors VS 2x Motors, you have twice the torque output, or another way to think about it is you have half the load requirement on each motor. So it will be harder to get each motor running at maximum power, depending on your weight & riding environment you might not be able to get them to peak at 80a each ever.
Hi thanks for the advice. Good luck with the build. I heard the mboards batteries are suspect. Witch is sad because I was thinking about buying one. They are a little cheaper packs an they have more options. I might build my battery. Or i might go with one from Chi battery. They have 30q cells an 40T cells witch have more out put. Good luck with ur build. Im going with a Dual Vesc from flip sky. I hope the Hobby Wing works well. I heard they have a smooth acceleration an breaking.
Thanks for the advice Onloop. I was planning in building or buying a 12s3p (that would give me 15amps a motor, right?) but I had spoken with another person an he was recommending 12s6p That would give me more amps per motor, 30amps correct? But is that 12s6p too big? Especially since im going NEST pack.
If you can go with a 12s4p 30q pack that would be a better match. Anything less than 4P and you might risk over discharging.
Most people building a 4wd beast wouldn’t skimp on the battery, whats the point of having a beast board that is limited by battery.
I think you would be better off dropping back to 2wd and spending more on the pack.
Finished! Took my first ride today Awesome (awesome because I have no other point of reference yet). But the Hobbywing acceleration and breaking is very smooth. Some day I’ll report how the battery does.