How many volts is 1% of GTR set? Some people have pointed out the 35E voltage sag. But to me it looks like a strong cell at low voltage. From now on, when making battery pack with 35E or 50E, I think it is good to lower the cutoff start voltage. However, it is limited to the case where it is not a power board. Is this idea correct?
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Perhaps we can focus our intention to Evolve rather than general engineering discussion. They are interesting and I will follow them with pleasure, but let go back to main subject. 3rd generation of Evolve.
I am pretty interested to read/analyse real condition hot run tests. Did someone with medium to heavy weight run some tests (uphill, stabilized speed run using a stadium ring, slowdown capability. 50m, 100m, 400m, 1km, 1mile run with battery consuption and speed monitoring (for 80-110 kg riders)?
I will try to do my best to put my name on a Evolveās demonstration tour in Switzerland or France, but to prepare test, some guideline will be perfect.
I am now allowed to take the GTR out and about and let other people ride it, so Iām 100% looking to get as many types of people on it as possible. Will report backā¦
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It kicks down into eco mode at 1%. The remote will vibrate to let you know starting at about 5~6% but remain into GTR until 1%. I donāt think theyāre using voltage to determine when to kick down thoughā¦ Thatās what the old ones did and thatās why there were so many complaints
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I think you should skim through the posts that are not relavant to you or your preferences, because I for one an following the engineering discussion about this new board and itās internals with interest. This thread is about the new GTR, and what makes the new GTR interesting is the new drive train and battery pack.
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@sofu can we get some more info on this?
What are those brass inserts connected to? Are they only connected to the lid, or do they actually support the weight of the battery?
If the pack is hanging off of these then Iām very concerned. Those kinds of molded inserts are notorious for stripping out of plastic. There are MUCH better kinds for pullout resistance. You can already see that 2/3 of these have begun to pull out.
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So thereās a plastic cover that goes on top, that holds the inserts in. The silver screws (blue) screw into the plastic holes to hold the cover on, then the black screws (red) go through the cover into the brass inserts. The brass inserts are held in by the cover
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Hi @LEE,
Focus on new implementation and impact on utilization is exactly that I am expecting from here, my previous post was about patent discussions. So let continue with @sofuās Return of experiences
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Weāre a diy forum discussing implementation of a rarely used cell and the engineering of this board. If you want to speak about evolves marking plan I suggest going to the evolve forum and joining the hype train.
Hush now
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Oof, ya know thatās not too greatā¦
Iāll withhold judgement until these get a LOT more miles on them. But I wonāt be surprised if these cause issues in the future.
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If the inserts are moulded around during manufacture then they will be absolutely fine, donāt worry. I agree that if they are push/press fitted, post injection moulding, then you have increased chance of failure. Given that they wonāt be selling 100,000s of GTRs it would be sensible for them to pre load the tooling with the inserts prior to injection. Sure it increases cycle time, but I think in the business of esk8 enclosure manufacture where numbers arenāt huge it would pay off to do this way.
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Lol my laptop disagrees. The majority of them have ripped out over the course of 2 years.
These have much better pullout resistance, and they are inserted post molding.
Itās not exactly in their application description, but these can be inserted with heat post molding for a very strong bond.
Ones like these are not very good.
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yeah the second ones, the broach inserts, are what I was referring to. We used to push fit inserts here at my factory into PC mouldings but found them to damage the intergrity of the component as they were pushed in. Itās been a while since I did insert moulding so maybe things have progressed since I last did it. (the first ones you linked) 
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The bottleneck really is the plastic at this point, hopefully evolve used The Good Stuffā¢
Iām sure they sprung for quality my friend
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Thanks for the answer. We DIYer know the remaining amount by voltage. Ordinary users know the remaining amount by percentage. Since Evolve is a board for general users, it may be necessary to express it as eco mode at 1%. I am still interested in the conditions for transition to eco mode.
On this occasion I tried to do GTX battery mod. However, in low-discharge and high-Ah cells, isnāt old BMS and old ESC that become eco-mode at 35 V useless? I think so.
Could someone who is knowledgeable with batteries (Moreso than the crappy explanation I am going to attempt below) explain to me whatās going on with the sag?
The pack is, for the most part, designed to draw 32A, Given this, with AT Tires carrying the average man + gear up a hill (About 180lbs), how does this pack have āNo sagā. It would surely have to be drawing the āBurstā of 52A to maintain a reasonable speed & torque (Given i know speed is tied to voltage but you know what I mean I hope)? Especially given the low kv motors, which would help it get off the mark with a low battery but surely would not help on hills/grass keeping a good speed?
If this is the case, there is a HUGE problem. For optimal cell life, from my own research, you want to try to draw about 65-75% of a packās potential discharge, thus keeping the cells at a minimal level of āstressā and minimising sag issues when the cellās voltage has dropped, allowing 30Q packs to go into the thousands of cycles if kept well in terms of charging from 20-80% capacity too. If evolve is withdrawing 170% of the cells recommended discharge regularly (13A / 8A), would this not absolutely destroy cell life? It would WORK for a while, but surely, after 2 months of riding, the pack would sag massively and cell degradation would set in very early? This may not be the case, I suppose we would need someone to use some kind of advanced BMS to actually genuinely record how many amps the ESC is trying to draw over an average ride with a normal weight male rider to see if this issue would happen?
The bigger issue is, reviewers wonāt know about this. I trust Sofuās review of the product, her board mustnāt be sagging (Given she will be significantly lighter than the average male rider or a chonky boi like myself). But is there a catch in what iāve explained above or should the product work fine?
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All batteries sag, there is no going around that, the problem is how you deal with it, if you have a protection system that only takes voltage into account you will have problems, if you actually measure the energy of the pack and know how much there is remaining you can allow the voltage to go down and still keep pulling full current at low state of charge
Have you ever seen logs from a Tesla launching at full throttle? Around 50 V sag in a 400 Vish pack
About cell life, the problem is that there isnāt a lot of data on pulsed application only continuous charge is discharge that hardly reflects how the cells are actually used
@sofu really good review, nice to see someone tearing this boards apart and showing the guts instead of taking it around the block and saying its good
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Right, but the issue would mainly be drawing far OVER the recommended amps for a significant portion of the ride, (i.e needing the full 50A to get around on hills and stuff) would destroy the cell life, not necessarily pushing the cells even at low capacity.