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[DonTom]

Look what happens with their own specs with the new battery.

The 13.4 KWH  battery range is 124 city, 100 combined, 80 freeway.

The new 21.5 KWH is 249, 143 and 112 miles.

That is in percentage of range improvement as 100%, 43% & 40% increase with the new battery.

I assume the 80/112 freeway miles is at 65 MPH.

I assume at 80 MPH, both batteries could have around the exact same range.

At 100 MPH, perhaps our old battery has a better range than the new.

That's why I would like to see a chart on each,  like Tesla has. I know my Tesla Model 3 gets 420 miles of range at 38 MPH, 320 at 65 MPH. etc.

With the new battery, I expect the nominal KWH reduces a lot more with load than does our old battery. I have explained before, with batteries, a KWH is NOT always a KWH when the load changes. They could rate them where the KWH give the very best numbers.

The big advantage of the newer battery is at slower speeds, where the range doubles. As the speed increases, it looks like the difference becomes less and less between the new and old battery by Energia's own range specs.

If going  fast enough, is it possible that the older battery gives better range than the new?  I kinda assume such is possible, say at above 100 MPH.  Can somebody here explain if  such is really possible?

-Don- in rainy Payson, AZ (RV)

[BrianTRice@gmail.com]

I'll hazard a guess from this, that internal resistance on the new battery has a different (steeper or more quadratic/exponential, say) curve on load current than before, unless weight and girth somehow changed enough to warrant that efficiency loss.

Remember that P(lost) = I²R(internal), and R(internal) for a battery can be non-constant per current, so there might be a surprising (cubed-ish) effect out of what seems like a subtle curve change.

Now, since Energica proved this technology through racing, the hypothetical thermal effects I'm inferring would be fine or within parameters. After all, cooling by airflow and the internal coolant loop at speed is probably the easiest.

But the increased voltage droop at the battery terminals that determines what the controller has to work with is the supposed consequence that would explain the figures.

It's possible that internal resistance while charging is different, but I hesitate to speculate, and the larger battery benefits from having a lower C-rate for a given amount of current flowing into the pack (distributing current across more Ah-capacity cells, which is what such a breakthrough is for).

[DonTom]

Now, since Energica proved this technology through racing,

Which probably means the battery is designed more for racing (a heavier  load but for a shorter time).

The real test will have to wait to see how much range improvement riders get at the higher speeds in the real world. Some may be disappointed at higher freeway speeds, based on some of the range data released already.

The 21.5 (18.9) KWH battery has a rating of 62% better than the 13.4 (11.7) KWH battery but only has a 40%  better range on the freeway. If at  higher than legal speeds, it is most likely even lower than that 40%-perhaps by quite a bit.

-Don-  in Rainy Payson, AZ (RV)

[Crissa]

Remember, batteries like discharging slower.  So it's nearly always going to be that raising the battery size will not give a linear increase at maximum output.  At some speed the increase is the same as the size increase - above that, it's less, below that, it's more.

But nowhere really should the bigger battery not still go further than the smaller one.  It's a curve.

-Crissa

[BrianTRice@gmail.com]

Increasing the battery size reduces the C rate of discharge for a given power demand. So the cells should be under less load / current for a given speed, because this battery upgrade mostly only changes the mass of the bike, not its drag.

That’s why the figures are worth considering to be an indication of the cell performance having changed in relation to the discharge rate.

The low speed range improvement is proportional to the capacity change. At high speeds, that diminishes. The capacity change isn’t matched by a demand change, so there’s something about how that is delivered that has a new loss.

[DonTom]

But nowhere really should the bigger battery not still go further than the smaller one.  It's a curve.

-Crissa

You need to define "bigger".  There are so many possible variables when they can rate the new lighter (smaller?) battery in various ways.

Sometimes NO rating is more meaningful than the rating. Take the batteries in this RV, for the house section, for an example.  True deep cycle (NOT marine deep cycle).  A CCA or a MCA rating means the battery is too cheap to use for a decent house RV battery. No fast discharge rating  at all usually means its a good battery for very low currents for a very long time (the opposite of an engine starting battery) such as for the 12 volt house lights. However, it can still be used to start an engine, but won't last long under such use. Same if an engine starting battery is used for the house battery.

There is also something called RC or "Reserve Capacity". That means the AH spec where the battery is expected to be used the most. That stops most of the cheating with the specs when batteries are compared across brands.

I tend to think many other batteries often cheat with their specs by rating the battery where they get the very best numbers for KWH even if the battery is not expected to be used in that load range.

Energica's own range specs show that 60% more KWH can only give 40% more range at higher speeds.  However, that same 60% KWH increase also gives 100% better range at slower speeds.

I just wish it were the opposite. I like the Energica for the freeways and faster roads and the Zeros for the mountains and in town stuff.

It's the freeway range I want to see increased the most on the Energica.

-Don- in rainy Payson, AZ (RV)

[Crissa]

Right, and no matter how you make a battery contain more, no battery known to man will not have a curve where it performs longer (more watts) at lower amperage load than at a higher one.  (well, there's a small point where the load is below natural discharge, but that doesn't really count.)

You always end up with a curve.  Maybe we'll have batteries some day that discharge evenly at the high load needed for highway... But they'll still probably be super-efficient at lower loads/speeds.

-Crissa

[BrianTRice@gmail.com]

Well, if Energica actually invested in highway aerodynamics, it would benefit better from the pack capacity increase, assuming these hypotheses hold up. But that’s not their market or in their interest. So we’re stuck paying for fast charging on a battery with a warranty too short for touring, or dealing with competitors’ limitations. Either option is valid, but not fully satisfying.

[NEW2elec]

The aerodynamics at high speed riding is the range killer.  It's basically 4X the energy for 2X the speed.  The air starts to stack up in front of you becoming more dense and requires more energy to over come it.  Same for gas powered or even man powered.
 
But the first thing you have to do is change to whole motorcycle into a low recumbent style and then enclose the whole thing in an aerodynamic pod if you want to take the concept to fruition.  Anything else will pale in comparison.

Like this but electric motorcycle of course.

http://www.recumbents.com/wisil/hill/RobWoodInFairing.jpg

When I was still racing bicycles there was a guy who would go on the training rides on a recumbent bike and he could keep up at the back of the pack even though he wasn't in nearly as good of shape as the rest of us.  He would try to get us to buy one (from him) and tell us, just think how fast you guys could go on this bike.  Of course there were no takers, but it was a more aerodynamic ride. 

[MVetter]

Y’all ready for a little Occam’s Razor?

“Maybe the 80 miles at highway speed on the 13.4 pack is unrealistic and it’s closer to 65 miles.”

[BrianTRice@gmail.com]

If the old statistic is unrealistic, then so would the new statistic be unrealistic, per Occam's Razor.

Let's not talk aero here. We're just trying to understand how this pack works.

[NEW2elec]

Mvetter, yeah it does work both ways, no reason to trust one set of figures by the company and not the other.  I know the company numbers are the "most optimum" specs and my results may vary.

Well, if Energica actually invested in highway aerodynamics, it would benefit better from the pack capacity increase, assuming these hypotheses hold up. But that’s not their market or in their interest. So we’re stuck paying for fast charging on a battery with a warranty too short for touring, or dealing with competitors’ limitations. Either option is valid, but not fully satisfying.

Brian on one hand I agree aerodynamics are a method to get more range.  You bring it up often.  My point is where would you have a company take the aerodynamic design to?  Sport bike fairings without the stylish air scoops and angles?  Any fairings for an upright motorcycle are a band aid on an ax wound.
To get real improvements in energy use you have to get low.  The problem is people don't want to get low.

As for the battery numbers, they are a similar curve to a Zero SR with and without a power tank.  A claimed 40 mile increase in the city but only a claimed 20 mile increase at 70 MPH.  Rider weight and road conditions being equal, the Zero can go farther on every kWh of battery due to it being a 150ish pound lighter motorcycle.

I hope to see some real world reviews and rides of the new battery powered bikes and take some averages from there.  In the end I do have no doubt it will be an improvement over the old batteries and would be a great improvement at the slower speeds of city and back road riding.

[reini]

The 13.4 KWH  battery range is 124 city, 100 combined, 80 freeway.

The new 21.5 KWH is 249, 143 and 112 miles.

Question for the current Energica owners: In which of those 3 categories would your range fall exclusively on twisties? Here in Austria there are lots of mountain roads, most of those with a 100 km/h legal limit. Just wondering what to expect...

[DonTom]

Question for the current Energica owners: In which of those 3 categories would your range fall exclusively on twisties? Here in Austria there are lots of mountain roads, most of those with a 100 km/h legal limit. Just wondering what to expect...

Expect a bit better than "combined".  Sometimes a lot better, because there is usually a lot of regen. Almost as good as city at times.

My experience with electric bikes  in the curvy hilly paved  roads around Auburn, CA show  excellent range.

-Don-  Payson, AZ (RV)

[MVetter]

It makes a lot of sense the 80 mile range is an old number they published and never corrected, and the 112 mile range is what they're actually getting now. Simple question:

Has anyone gone 80 miles at 70mph on a charge? I haven't. I'd say it's closer to 65-70.