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[jotjotde]

Hans gave some data of the battery of his EsseEsse in his recent post (https://www.electricmotorcycleforum.com/boards/index.php?topic=11314.0).

That made me look at my charging data at home which I would like to share with you (Ribelle RS MY22).

Having a plug-in-counter installed which should be fairly accurate, I recorded 29 charges over the last 4 months. Not included are the CCS charges outside my home.

In the attached diagrams you see the calculated real capacity of the battery when a charge is linearily extrapolated to 100 % SOC.
Example: Charged from 40% to 80%, counter showed 6,7 kWh. Calculated real capacity is then 6,7 kWh * 100% / (80%-40%) = 16,8 kWh.

At home I slow-charge overnight usually at 8 A (1,8 kW) either to full (if I plan a trip the next day) or only to 80% if nothing specific is planned
(reason: I read that letting a fully charged battery sit at 100 % is detrimental).

The data are to be taken with an accuracy of approximately +/- 0,2 kWh.
Reason for that is that the charging often stopped during the night but the cooling fan of the on-board charger kept running which according to the counter is drawing 55 W of power.
There are two figures odd-out, there I might have misread the numbers on the display of the counter.

Still, what you can see is, that the real capacity of the battery is a bit over 17 kWh.
One time I rode the bike to 0% and charged it to 100% with 17,4 kWh, which is consistent with the Arithmetic mean of all charges to 100%.
'Personal best' was 18,4 kWh charging from 44% to 100%.
Expectedly charging to 100% pumps more into the battery, probably due to the balancing.

What is not clear to me is the difference to the numbers stated by Energica:
21,5 kWh maximal capacity
18,9 kWh nominal capacity (88% of max)
17,4 kWh real capacity (81% of max)

The only explanation I have for that is, that Energica's numbers are from an ideal world with optimum temperatures, beginning and ending charges at optimum SoC etc.
What do you make of that?

[Skidz]

At the end of the day I don't care how much i put into the battery, it's what comes out of it that counts. My 2016 DSR did my commute but barely, getting me to work often with only 1% left. The 13kWh battery then consumed 11kWh max, with the charging efficiency that means (90% of 11kWh) 9.9kWh reaches the cells.
On the SR/S not much of a difference, also just made it to work with the 15.6kWh battery but with 10% left. Charged with 12,8kWh means 12,7KwH reaches the cells.
The Ribelle takes 14.7kWh for the same distance, but at very different speeds. On the Zero's 100km/h was pushing your luck and if there was no traffic I could not make it to work or home. On the Ribelle I drive 10km/h faster than allowed fairly constantly. I arrive with 20% or more left. So my Ribelle is 14,7/.8 * .9 =  16.5kWh net, extrapolating the 20% left and a charging efficiency of 90%.

Every EV builder gives you flaky numbers, look at the ranges they predict which nobody ever gets in the real world, or charge speeds, or battery capacity. What matters to me, is that I comfortably do 150km highway at highway speeds and then have enough left to find a charger.

[wadejesu]

Hence the famous or infamous saying " Your mileage may vary "

[Hans2183]

Did you take charge losses into account? That would also explain the higher values when charging slow during balancing. The slower you charge the more loss you get.

My numbers were from the bluetooth communication and can be found on the can bus data also. I don't know the exact reason but this is very likely done to improve battery life.

The used cells have a min and max voltage rating, manuf typically have them nowhere near those limits. So if 3.2V is max they for example use 2.9V instead to protect the cells. That is how Zero introduced their 110% charge option. We can see voltage on cell level if you're interested. There were some posts on Facebook also recently on this topic.

[Hans2183]

This was shared on reddit the other day

https://www.electricbike.com/energica-electric-motorcycles-from-italy/

And some of my numbers

[jotjotde]

Hi Hans,

Thx for sharing this. To be honest, I just can see that your battery is healthy 
The rest of the data I cannot connect towards a  battery capacity figure.

My numbers in this post are just the readings of the meter, so all losses are included.
The inverse dependence of loss against charge power was new to me.

But I understand that over a 6 hours charge time a loss of 160 W would add up to approx. 1 kWh which do not go into the battery.