Raptor 2 - power system discussion

Sometimes there is a reason why you want to have higher amps. One - two thing I can point out are better heat management, better quality material (last longer), doesn’t get damaged easily. Just same reason why boeing 737 is a huge success although they fitted in way bigger engine that they don’t need, because only using 20% of the load increases it’s life expectancy.

Because you get more sag… Ask @onloop why he puts a 40 amp fuse on his space cell, when the batteries cells are rated to 80 amps?

The closer you get to your rated max amp (assuming the rated max amp is valid and confirmed by people like Mooch), the more sag you get… This is a fact, which any person whose researched batteries extensively on this forum can back up. Ask chaka, ask jinra, ask onloop, and many others. They will tell you the same thing.

I’m sorry, and I mean no offense, but I’m done wasting my time arguing about it. You can either accept it as a reality or not.

But most likely, Jason will keep the 40a fuse on the battery pack for the the Raptor 2, which as I have already shown with diagrams even, will make the vesc-x a useless improvement in a dual drive raptor 2 in terms of it’s increased continuous amp rating.

Assuming the 40amp fuse as the amp limit we can figure what will be the max power of this board while integrating voltage sag. At full charge ten amp draw from a typical Li-ion with a 20 amp rating will be at 3.8 volts at full let’s say X the 40 amps = …

The most powerful direct drive board can do 1520 watts max before dropping precipitously within seconds from voltage sag. No?

By the way. I drive my 80 A max board with a 40 A fuse. Not recommended but on more than 1000 km i never had a problem. I guess my car fuse needs way more than 40A to blow. But Enertion might use other fuses. So @Hummie now i am curious. Just tell me what we will see in the future of you. More P batteries, A123 or Lipo’s.

From looking at all these claims and reading the true figures it does look that it’s not going to be much better than raptor 1 and not worth the extra money. Feel sorry for anyone who has paid more than $1000 as personally don’t think it’s worth much more.

i have no plans but am surprised we all let the important fact slip through that the motor and esc typically isn’t near their peak abilities with these Li-ion battery packs. The real power limit is the batteries and power is so important

Didn’t evoheyax switch from the batteries to the fuse as bottle neck? But now really let us stop here. Otherwise we kill this thread with bitching around. @evoheyax impressive board btw. (seriousely)

I don’t think we are bitching but just figuring out what’s going on. Talking about the facts should always be welcome

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Love the debate, but maybe it should be on its own thread. Modetators please move. Raptor 2 debate/discussion. Maybe the others may want to call it.

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Ok now that we have a thread that is just for RV2 my interest with the new board is going to be how reliable it will be. The vids that are coming out against the V1 Id like to see powering on numerous laps up and down hills for say 20mins. Rather than just a power lap on veladrome or once up a hill. Ok it will need to be sped up.

I like this debate too the VESC-X should be an improvement for FOC which is a big deal for some people

But a video by Jason for comparison just now could also be rigged to make the raptor 2 loot better. Really he needs to get some beta boards out to 3rd party people to give some honest feedback agains diy board.

For sure there should be and we hope will be independant videos. Early days. He hasnt even got beta boards yet. But the comparison videos he was doing with Raptor 1 seemed ok. Albet you can edit what you like and set test parameters as you like.

Hes had parts tested, just not the whole early model yet.

Be good if he could do one against Evolve GT, the Raptor V1 dual rather than mono and new RV2. Big expectations.

He was meant to do a CGT vs Rpator V1 . That never happened. Might be logistics as owner of GT wasnt in his state.

Also to be fair. Do you see any other eboard conpany puting their product against opposition. Non. Thats because Enertion put themselves out there. They back their product. And they will have to to claim the powerfull direct drive mantle.

The real issue with the raptor 2 in my mind, is the battery. I’m sure there will be other hub motor issues too (I’m not going to do Jason’s homework for him).

The fact that Jason won’t say “this won’t be an issue because of x, y and z”, is because he knows I’m right.

@Ackmaniac if you look at the discharge graph for the LG HE2 (which is the cell I’m using), you’ll notice it’s normal at 20 amps (it’s max continuous rated amps) that it’ll sag to 3.8 immediately. That’s a .4 volt sag at full charge. If you discharge only 10 amps, it sag’s immediately down to 4. So half the current, and you half the sag. This is why I say, even if they are rated to 20 amps continuous, that amount of sag is not desirable on an electric skateboard. If you have a 10s4p pulling 80 amps, and a 10s8p pulling 160 amps, we can expect the same amount of sag. The higher the max continuous rated cell, the less sag we can expect. 18650s in this 20 con class all sag pretty similarly, but lipos all sag pretty differently. This could explain why your lipo sags more. You said it was also a laptop battery? This could explain the sag also, as those cells are likely cheap and not really 200 amp con cells.

The Raptor 2 with the current 10s4p will either have a lot of sag or will run way below it’s max amp rating. My guess is he’ll put a 60 amp fuse. This would make the vesc-x a needed upgrade, but will still sag quite a bit.

The fuse bottle neck is easy to get around, but it’s there because more than 40 amps will cause a lot of sag. I mention it to illustrate my point.

And @onloop, still waiting to hear your side of this. So far, nothing but silence…

So… I don’t know anything about voltage sag, but it’d be interesting to see where amperage is capped on other productions boards.

If hes pulling 30 amps for each motor, then like you said, the VESC-X was a nessecary upgrade. And if his hub motors can handle 30 amps continuous than I’d be pretty impressed, and it would therefor be the most powerful direct drive system.

Shortly wnat to make clear that i have a single board with 2 lipos 10S 4Ah 25C in parallel. So 10S2P 8Ah 25C = 200 amps. And they don’t sag as much. And i have the 12S8P battery made from laptop cells which sag much more because they are absolutely not build for that, but still do it. But the 25R are build for it and the 0.4 V sag is normal and not an issue.

Otherwise it would mean that they rate it to 20A but tell the costumer that they should not do that.

So what would those 3.8V * 10S = 38V be good for? At 40A on each motor (80A total) it would be 38 * 80 = 3040 watts. That is a bit more than 4 hp and maybe even too much for the most of us. But that depends on everybody’s personal taste and experience.

The 0.4 V sag is normal, but that doesn’t mean it isn’t an overall issue with the board. With sags like that, you have to stop at 3.6 volts per cell without load, as any more, and you’ll sag down under load past the 3.2 the community agrees we should stop at for the sake of the cells life span. In this case, the 10s battery is 32 min volts, 42 max volts. That’s a 10 volt range, with a sag of 4 volts, so 6 volts of usable energy. That’s almost half of the battery range in sag, which means you’ll get half of the range you would get with no sag. With a sag of 2 volts instead, you would still have a range of 8 volts, 1/3 larger than with the 4 volt sag. This means running at half the suggested rating would yield 1/3 better range.

Getting 25 miles on a battery this size is a stretch for any hub motor in my mind. If you are loosing 1/3 of the battery to sagging, than this is an issue. I never said the batteries are malfunctioning and not doing what they are designed to do, just that these cells in this configuration will either sag heavily, and under deliver on power. Or a medium of the two with still quite a large sag. There won’t be 80 amps of power without a large sag, which no one wants due to the range issues it will exacerbate.

I think your getting confused by motor amps vs battery amps. The two go hand in hand, but motor amps are always higher than battery amps. 30 motor amps is not that high. I hit 50 motor amps peak with 30 continuous per hub with hummies small hubs in 4WD. This is usually around 18 battery amps. I’m sure I could pull more, but like the Raptor 2, I’m limited by my batteries max amps. I am sure I can pull much higher amps once I solve my battery issue.

That is so much mixed up miscommunication here. Simple example, at 3.6V with no load a lipo is already empty.

Started to explain it but then you will come with the next stuff where numbers get mixed and taken out of context.

I know you don’t like the raptor 2 and you don’t have to, which is absolutely fine. Hopefully we will see in the future if it is a great board or not. Time will tell.

I will concentrate on source code again.

I’m trying to get to the bottom of the facts, not create bs to attack a board. I want the board to do what it claims, so the sake of everyone whose blown their money on it. Otherwise, I would keep my mouth shut and wait until it comes out and the problems are there. I’ve talked to many respected people in this community about this issue in private and they all agree with me and what I’m saying about this batteries problems. You seem to be a programmer, I am also. But I’ve spent the last 18 months studying electric skateboards, and the electronics in them. My ideas aren’t crazy, but we clearly disagree that using this battery, you will either have bad voltage sag or low amp limit, or a mix of the 2.