Range estimation value is extremelly unrealistic

[Atak Snajpera]

My battery:
SAMSUNG INR21700-50E 48v 25ah (real capacity is 24ah ~1150Wh)

Discharge curves

‌

‌

Battery was charged to 100% and then I reset the trip meter

‌

‌

After 29 km estimated range left was 233 km! That’s total bs because max range with average 7 wh/km consumption gives max (1152 Wh / 7 = ~164 km).

‌

‌

‌

I think that battery percentage value is also too optimistic. After 73 km I’ve used 512 Wh so remaining percentage should be around (1-512/1152)*100=56% not 72%! I think there is a problem how you map voltage with percentage value that’s why I strongly suggest this solution.
https://bitbucket.org/eggpower/eggriderv2/issues/238/custom-voltage-percentage-curve-in-battery

‌

[Adrian]

Hi Atak,

‌

Thank you for your message

‌

Can you please go into display settings → battery settings → at battery voltage please select your battery.

https://manual.eggrider.com/getting_started/#battery

‌

After that still in display settings → at wheel circumference please select the right circumference of your wheel.

https://manual.eggrider.com/getting_started/#wheel-size

‌

Let us know if this fixed your issue!
We are looking forward to your response!

‌

Best Regards,

Adrian - EggRider Team

[Atak Snajpera]

1. My wheel circumference 1970mm is 100% correct. Also double checked with GPS. Traveled distance matches GPS distance.
2. I DO NOT WANT percentage scale to end at stupid 43.55V (3.35V per CELL). That’s why I manually set 39V (3.0V per cell) in app. Default 43.55V makes no sense because eggrider would incorrectly report depleted battery at 43.55V even if there is still about 16% energy left until my 39V (3.0V per CELL). 16% is A LOT if you have big battery like mine (1150Wh). That’s still ~184Wh! With my current energy consumption (7Wh/km) I could still do ~26km with my CYC X1 STEALTH motor! For me that’s literally 2 rounds from Home to Work and back.

The issue is that you scale percentage LINEARLY with voltage regardless of end voltage point set by user. With default 0% at 43.55V (3.35V per CELL) it works because voltage drop is more or less linear. (see my my discharge curve for SAMSUNG INR21700-50E). However after 3.35V you have non-linear drop. Like I said before solution to this problem is ultra simple! Just allow user to configure his own voltage/percentage mapping in 5% increments. Am I asking for too much?

‌

[George Banea]

Hi Atak,

‌

We are looking to improve the battery algorithm but right now this is how it works. Keeping the voltage 0% very low is not that correct either because at low voltages the sag will hit the BMS protection. Think of the battery settings as parameters for measurement, you can tweak them to obtain what you want. In my experience getting a voltage a little higher than the real 0 and tweaking the battery capacity gets good results.

Can you please provide a trip export where you connect with the app: ride for 30 minutes then stop but keep the phone connected for another 30 minutes?

Please send the trip data by contacting us here: https://shop.eggrider.com/contact

‌

[Atak Snajpera]

In case if you are interested this is my discharge curve until almost cut-of point (36.4v). I was basically writing down volts and consumed Wh from eggrider after few hours of inactivity. (so called rest state)

I hope this will help you to understand how lithium batteries work and how to program correct discharge curve in firmware.

‌

[George Banea]

Hi,

Thank you for the information.

We are aware of how lithium batteries, just having an algorithm that works for every type of battery is very difficult.

I think with the parameters you have for the battery configuration you should be able to obtain something close to reality, is just a matter of experimenting with the values.

If you want, please contact us here and we can schedule a call. https://shop.eggrider.com/contact

‌

[Atak Snajpera]

I'm not telling you to create Perfect formula which works with every battery. Please allow user to manually tweak discharge curve every 5% step like I mentioned in my previous sugestion. Eggrider after all is for power users so why not give some freedom in this topic? I'm nerd/geek and I love tweaking things ;)