How should my charging solution be?

No, more closer to these

That one has a “Contact rating-0.5A 30V DC”. Aswell as it doesn’t provide where the positive, negative and ground goes.

I mainly meant that style and not that specific one. This one might be closer but curiously it’s 2.1mm plus or minus 25.4mm, that’s a pretty big margin of error. Sounds like the seller doesn’t know what’s going on…

I dont think I will get a sag if I use the tb vesc with it, will I? It has a 50A max

Dude stuff like this doesnt matter, plug the charger to this then just measure it with an multimeter if the voltage is in - its the other way around and boom you know where is plus and where is minus

Voltage sag has nothing to do with esc’s

Probably just a typo

You’ll always get some sag, it’s just a question of how much is acceptable to you and the batteries. 5ah 20c is right at the fine line of “barely acceptable” to me, but it’s probably fine.

Bear in mind that I have a tendency to overbuild my stuff.

So if I use 2x 5s 5000mah 20c batteries in series to a 10s battery, it would be nice?

Like I said, 5ah 20c is barely acceptable in my book, no matter how many in series. If I were you I’d either increase the C rating to at least 25 or 30, OR increase the Ah of the pack, either by using larger cells, or putting some in parallel.

I wont be a torque monster or speed demon, but it will work. Depending on weight and terrain you should be able to hit 20 mph and handle some small grades. The best lipo solution is using 2s lipo packs in a series of x5 to make a 10s pack. I built one using 20c lipos and it was a beast. Very fast and torque to the point that I could leave thane on the ground. Its pretty inexpensive too.

Check out this thread, it will tell you all you need to know about Lipo packs. @Namasaki is a genius …

Here’s something I did just for the hell of it :slight_smile:.

Only 20mph? According to esk8 calc it should be able to hit 25mph. Is it because of the discharge rating? I will bypass this in the bms btw. I dont think I want 5x 2s lipos, because it will take up alot of space, and is more expensive than just buying 2x 5s lipos. Im not sure how many people who have used bms with their lipos tho.

You might hit 25, who knows. I have found that I usually come in at 80%. Lots of people have used a BMS with lipos, look at the links I sent you and search.

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Esk8 calcs do not take into consideration voltage sag. Using 5000/20C packs at 10s, you will have voltage sag that will reduce your max speed and range. What I recommend is a minimum of 60C at 5ah and even then you will have a small amount of sag. With 20C at 5ah you might also have issues with your packs heating up and getting puffy.

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Okay, thanks! But my wallet is obviously not as big as yours, and the 60c batteries cost a lot more. Still wouldnt want heated and puffy batterypacks. Mabye ill go for 30c. Or a 8s system instead. The thing is just that there are few people using 8s, and therefore few brick chargers with 8s (33,6v). And then have a matching charging port to that brickcharger etc. BMS too :confused:

I use (and started with) 2x 5s 5000mAH batteries (20C) and I have found it fine. I’m a bit careful/timid on my board (can’t afford to crash) but go up some hills while commuting.

I generally cruise at about 22km/h (I know that’s slow, but I’m not limited by the batteries).

I also have my motor current limited to 20A in the VESC setup (running a 5035 125kV motor)… more than enough for me.

I would only change the setup for size/stealth/asthetics reasons.

Nice dude! What discharge rating does the batteries have? :slight_smile:

Updated post. 20C…

Thought they might be a bit low (in the month and a half that they took to get here) but I had nothing to worry about.

motor current isn’t decided by the battery. only the “battery amps” are true amps coming from the battery. So you could set your vesc to have a miniscule 20 battery amps and 120 motor amps and still only pull 20 amps max from the battery yet still have great low speed torque.

Totally. I get that. I figured that there would be some capacity stored in the VESC and tutorials I had seen suggested doing the limiting at the motor rather than battery.

I wanted to dull the acceleration for a while as I learn how to ride the board with motors.