@Namasaki how many watt-hours is your battery again?
(5Ah)*(37V) = 185 Wh
Just curious, because I have 275 Wh, but haven’t done a full range test yet. I was estimating 15-20 miles based on an average of other people’s numbers. Using your data point, that’d put me at about 20mi
My batter is 10s/5000 Is your battery 10s/7400 ?
I am running 12S (4x 3S) @ 6200 mAh
(6.2Ah)*(44.4V) = 275 Wh
Looks like you are using around 13.7 Wh/mi. I was estimating 18.5 Wh/mi in my low-end calculations based on random range posts
@jmasta @Namasaki I’ve run 10s3p 7500mah li-ion 25R’s and 6s2p 5000mah lipo’s in the same board and I get identical range, within half a mile or so.
The lipo pack provides a lot more torque, so I assume I’m loosing watts on the li-ion because it hit the throttle heavier on hills.
I’m going to test with the 30Q cells too. But if I had to decide today I would sell the li-ion pack and build me a lipo pack with x4 8000mah 5s lipo packs (10s @ 16000mah).
It’s really hard to guess what your maximum mileage will be. I did not expect to get 14 miles out of my battery even on a flat run. On a run with lots of hills I only got around 10 miles. My Li-ion pack was 10s/9000mah it got me 28 miles on flat run going 10mph or less but it got no more than 10 miles on that run with lots of hills.
I think the issue is voltage sag. Because Li-ions have such a low C rating it takes a lot of them to eliminate the sag. Some have said that the 30Q cells are better but they are only rated for 15a per cell. So a 4p pack is only 60a.
When I drew very little current from my Li-ion pack it did fine but when I tried to draw more current, it did very poorly. It was supposedly a 60a pack. The 25R’s are suppose to be 20a cells but maybe they are overstated I’m am looking forward to see what your results are with the 30Q cells. How big a pack are you making?
Either a 6s5p or a 10s3p, not really sure yet. I hope they are better than 25ra because they suck. 
The range should be about the same either way but 10s will provide better performance. I just checked my individual cells after running the battery pack down to 33v 3.40 3.42 3.48 3.39 3.44 3.49 3.46 3.44 3.38 3.39 from highest to lowest is .11v Does that seem better than normal when discharging without a BMS? It’s been so long since I didn’t use a BMS that I can’t remember.
30Q cells are rated to 15A due to life cycle. This is straight from the data sheet.
And remember this is continuous. We do not run continuously at these power settings so temps won’t be nearly that high. They also charge at 4A per cell, on a 4P pack that would be 16A so you’re going to gain some cycles by charging slower
The question here is how do they perform in terms of voltage sag under load and range in real life application compared to 25R’s and Lipo’s
That’s what I am trying to decide. Would 6s5p offer more immediate torque that 10s3p?
That looks fine to me, I usually see drift of about .1v.
Ta da?
This is real world data… tested independently by Henrik and I’ve confirmed his data with my own on several different battery chemistries including Samsung 30Q and 35E LG HG2 and MJ1, Sony VTC6, and Panasonic/Sanyo B and GA cells
The voltage sag in the graph above is the voltage difference at a specific used capacity. For example, if you used 1.5Ah/cell and then went from no-load to 10A/cell, your voltage sag on 25Rs would be 0.4V per cell and your voltage would be ~3.6v per cell at no load and ~3.2V per cell at 10A per cell.
On the 30Q at the same discharge of 1.5Ah per cell, there is a voltage sag of 0.25V per cell when drawing 10A per cell. Voltage drops from ~3.7V per cell at no load to ~3.45V per cell at 10A.
IF your voltage limits are set at 3.2 and 3.0, this means that you would hit this limit with your 25R pack regardless of having 1Ah left in them while your 30Q would still be going strong.
I don’t get how this is not real life application data…
If you’re using the same motor. The lower voltage will have a lower max speed limit. The higher current will mean more losses across wires etc, although it should be able to produce more torque since your current availability is higher.
You can also tweak this in your VESC settings by increasing your max motor and absolute current settings. Power in = power out. So you can accelerate at ridiculous power by messing with your motor current settings.
For example, you have 36v and 60A available from the get go, that’s 2kW. If you set your motor current limit low (40A) then at 10% throttle, you will hit that limit and won’t be able to use all the power available from your battery. If you set it high at like 150A, you will get more power at the low end. I forget what the math was. Just search for devin’s threads… it’ll be the equation posted about 50 times per post and 1000 times per thread
LOL, no doubt
It’s Labratory data. And though the 30q out performed the 25R, they both have considerable sag compared to Lipos.
I have flight test data, does that count? 
That’s what I’m talking about.
I was out of town for a while so I never got around to checking the charger - did it the other day and it is reading 42V. I charged again and it seemed to sit at 41V forever. Is it possible that crappy wiring is responsible?
Had a real fun ride this morning. people stopping me to ask about the board. I think I have two separate issues now - I think the belt slips sometimes when breaking, can be really scary. Also think the wheel loses traction sometimes when accelerating which causes the same effect - my board jumping forward.
Did you pre-balance the packs before putting them together?
I did. Maybe its time to double check this though.
