New build - Trampa eMTB | E-Toxx | MAX6 | SK3 149kv

@EssEnn: I have a 10amps balance charger. It is around 4 hours fo full charge.

@Nowind: Thanks bro. I totally missed this detail.

Do you have a watt meter? Would be cool to find out how much an emtb ‘‘hogs’’ while riding on grass! I rode just on asphalt today, with 6s 192kv 9inch wheels, 4.33 ratio and it pulled around 60 amps / 1200watts (max). About 5-20A, when cruising (5kmh - ~20kmh)

@Okami: no, I don’t have one. Which one do you use?

@ciocan

I use G.T. Power analyzer. There should be some on amazon. On ebay they are quite cheap. Around 15usd max.

150A peak. Continous is about 70A or so (at least what description says)

There are multiple versions. Turnigy also makes some. Though there was a test on youtube and they dont work that precisely in low wattage range ~50w

@Okami I just installed the calorimeter. From what I saw it tops around 70-80 amps and 1500w

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Cool! Nice to see one more eboard rider using it!

I now wonder how much amps would one motor consume in your situation (terrain)…

Maybe when riding on grass it is more productive to have 2 motors instead of one!

Does it also show average consumtion or such? I’ve seen your model but have not focused on the details and differences between the one I have.

Does not show average consumption, just what is displayed on screen.

It seems that is not working properly for totals. It is setup for 100Ah (4x5x2 cells of 2.5A) After 20 minutes of riding the display was 97% full but when I checked home with the balance charger it was 23%. Something is wrong, I’ll investigate more at next ride.

It seems that You didn’t get Your battery capacity correctly, I guess 100Ah is wayyy to much for this battery case, it would have to be ten times bigger to accomodate such size of battery.

You have an 8p battery, if each cell is 2.5ah then your total ah is going to be 20ah. 23% is likely the accurate number.

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@ciocan at what level do you intend to stop discharging cells? Also - does your charger charges till 4.1 or 4.2v per cell?

I usually try to stop at around 3.5v per cell. My turnigy charger shows that about 10% capacity is left at this level. Though it only charges till 4.1v per cell in default config… so 4.1v is 100% and not 4.2v.

Wrote a long reply to only find out you also got 80w charger… that’s why it takes so long to charge the cells for you, too.

Have you considered buying a more powerful charger?

I think it is worth to consider chargers in 150w+ range, if you’re usinh batteries larger than 8ah.

I use ~62w for charging (out of 80w max it could offer) and it already takes around 3 hours to charge about 7ah into the pack or about 1ah in 25minutes (6s at 2.5A)

@Okami

4.1 is the charging voltage for li-ion on my charger. I charge them until around 4.05 and I discharge when riding around 5%. (I made a mistake couple weeks back and I overcharge to 4.1 for 15minutes more because the cells were unbalanced and was .05 difference. Because of this, 3 series went unusable)

I have a dual balance charger with 2x100 watts. I can go up to 10A each row, and it will charge around 3 hours for 8p. The average current input for 8p was around 7A. Now I have only 5p left and I charge with 5A.

Well, if you charge them as 4s or even 8S, I believe you cannot get 10A… 10A x 16v = 160w, and for 8s (4x 8 =32v)… the wattage would be 320w already…

So, it is better to look at watts rating of the charger, not the amp rating… I believe you can charge 2s pack at 10amps… as that would be around 80W…

It is safe ok for li ion to go till 4.2, so I think that is a safety margin they have made, to just charge till 4.1… and it also of course, prolongs the life of li ions…