How do I properly set brake curve? Brakes dangerously too weak down hill!

I’m sure this topic has been covered a million times but I cant find any clear answers on how to do this so any help would be greatly appreciated… I have 2 vesc 4.12s on my 10s6p mountain board and I have decent braking distance on flat ground but any kind of hill greatly reduces my stopping distance to a dangerous amount of space. And if Im moving faster than about 15 mph down a steep hill and hit my brakes 100%, I almost dont even decelerate until my speed drops slowly lower than 10 mph and then I rapidly decelerate the slower I get. high speed braking is super weak but low speed is pretty strong. The negative amps are set to -25a each motor but i dont want to go higher because i dont want my low speed braking to be any harder than it its. Also the braking watts hover around 400w per motor from 26mph to dead stop but my watts on acceleration peak at about 1500w per motor and my motor max amps is set to 35a per motor. Btw, Im using a cheap Chinese remote so Im sure that might have something to do with it but my mapping is set correct.

For stronger brakes at higher speeds you will need to increase the ‘battery current max regen’ try setting it to -25 per side.

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Correct me if I’m wrong, but wouldnt that throw way to many amps back into the battery? If I did -25a regen each vesc, that would put 50a regen charge back into the battery right? My cells are only rated for 1c charge.

You can overexced the Rated battery figure for a second here and there - Try to brake in short burst bursts.

also, you have sets of 10 cells… so you can pull in 50 amps no worries (double check this)

otherwise - always check the cells before you buy this is why the 30Q are favorites

Yeah my cells arent rated for that, I built my pack out of flat cells and I’m not certain on the burst charge rating so I’m going to play it safe at 1c charge that I know they can handle which is 2.8amps per cell, 6p makes that 16.8a that I can push in the batt on regen… so 8.4a per vesc… I think… I’m still pretty new to all this so not saying I’m 100% right but I want to play it safe… I know I can burst more than that in there but on hill braking it could be for longer than I’d like… So is increasing regen the only way to get stronger brakes at higher speeds?

you have your ,math wrong .

so samsunng 30q

10s 4P - You can charge between 1-4 amps 4 is the highest before damage could occur.

but thats 4 x10 sierise, meanings 40 amps coming in heance why you can charge in 2h

in bursts i can pull in 80amps, hell i can charge at 8 amps, its not smart (also its an hour of charging vs seconds)

Ok, I was told that if 1 amp was applied to the whole pack then each P group would have 1 amp applied to it and the 1 amp would be divided between each cell in the p group… I guess I need to do some more research… so if this isnt too confusing the way I word it, if 1 amp is applied to a pack, would the 1 amp be divided up equally between each P group thats in series and then even further devided up between each cell in the P groups?

So theoretically, a 10s10p pack charging at 100amps would have 1 amp applied to each of the 100 cells? Sorry, but I really gotta dumb stuff down to understand it at first…

You need to litterally mention the type of battery exactly you are using to really be able to answer.

But since 30Q is the gold standard, 10s/4p results in 4amp charger (fast charger)

I can then charge full in 2h.

Or 1h at 8amps but then im just asking for shorter battery life overall.

another question is are you full battery - in which case you need a solution for removing extra power - heat.

@cskarke If you set your maximum brake current higher, it doesn’t really matter because it’s such a short burst. I have mine set to -25 per side.

@TheSebas yeah I’m going to experiment a little bit and see what I can do. I really dont need too much more than I’ve got already.

meanwhile I was planning on having -30->35a per vesc on dual street board.

#LoLz I think I’ll start with -20 per now.

@ESK1, You literaly have no idea about the theoretical part of the batteries :man_facepalming:t3:

@cskarke

This is correct. Series dont matter when talking about amps.

@ESK1 doesnt. You, @cskarke were right! I written it a bit odd to get, sorry🤦🏼‍♂️.

About the battery, you have to decide whether you want to have good brakes( increasing the battery regen current and exceeding the max charge current for a little time, which has a really minimal affect on the battery and may shorten its lifetime for a fraction) or play it safe (for the battery, not you) and get the full battery life span but never feel ok because the brakes arent good. Almost everyone chooses the first option :slightly_smiling_face:.

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@Moko ok got ya! I understand now! No worries!