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[talon]

It's been a while since I read up on the subject, and I've mostly skimmed this thread, but comparing some Lead Acid composition battery's ratings with various Lithium chemistry batteries isn't exactly apples-to-apples.

My understanding is that the Peukert Effect does not apply to lithium but does to lead acid. Anything within the acceptable continuous range of current for a lithium battery should give almost the same capacity. Conversely, lead acid takes an extra, varying hit at all rates. IIRC the Peukert Effect is the reason that leads to lead acid being rated given a certain load or time that is chosen on industry standards ("20 hour rate"). Lithium kind of has this, but in a broad (ex: 0-10C rate) kind of specification, with very little gain for lower rates.

So wind resistance may affect the range with the square of the speed and other factors like density of the air, but the actual capacity out of the lithium should be *roughly* the same for high or low loads. On a side note, I read somewhere that lead acid has a non-linear charge efficiency that may be related to Peukert Effects (somewhere around 50% through most of the SoC range). They both suffer from some internal resistance and obviously cut-off voltages then apply and account for any load-related loss in capacity, which shouldn't be all that much with lithium? Maybe cut-off 5% or 10% early for being sagged a volt or two, which is accounted for in Zero's ratings (70miles @ 70mph for the ZF13.0). I don't know if sagged voltage degrades cells the same ways that being overdischarged does, so perhaps they can tolerate being a volt or two lower than cutoff if it will rest higher?

With the numbers we are dealing with here, I don't think the 21.5kWh pack could give less range than the 13.4 at any speed the motor and controller can continuously put out.

[Crissa]

High loads (or temperature), increase the internal resistance in lithium batteries, which loses some of their efficiency.  Plate surface and cell number change the optimal discharge point.

It wouldn't matter for many uses, but for a vehicle, we really can try to draw or charge massive amounts which gets us to the ends of the curves.

-Crissa

[Frank]

Actually, high Temps tend to decrease internal resistance, is this what you meant to say?

Sent from my SM-T380 using Tapatalk

[Crissa]

No, that's not what I meant.  I meant that 'high load' or 'temperature' can cause internal resistance.  What the temperature or load range depends on the battery formula and configuration, of course.

-Crissa

[Goetzuwe]

The battery doesn't have 21.5 kWh but a net 18.9kWh. Therefore, reserves are surely incorporated.
You also only need the power of xxx kW for a few seconds. A topic could be the temperatures if it is
permanently above 40 ° C, from 50 ° C (122F) the red area begins where the electronics reduce the power.
(sorry I write in °C since I live in Germany)

[heroto]

Please never apologize for going metric.

[Crissa]

Just label the numbers, that's all I ask.

-Crissa

[most]

Guys, are there any real world comparisons available now? Like charging curves for OBC and DC, or any range comparisons? Range comparisons at 60mph is most interesting for me as this is my local limits (again Germany) for country roads incl twisties.
I‘d be interested in that - just sold my Zero DS and about to sell my BMW R1200GS in favor of a Esse MY19 (dealers demo bike) that I could pay cash. Or wait, save some more bucks and get the 21.5kWh battery...?!?

[Goetzuwe]

About the range of my Eva Esseesse9 +
Yesterday I drove 3.5 hours / 180km (112miles) through the Sauerland (Germany / NRW) in very winding, mountainous way.
I shut down the battery to 19% (without recharging).
In warm weather, the battery should last longer (10-14 degrees).

Now I have new the TomTom Rider 550, it is very helpful, you can create curvy round courses with more fun than drive on main streets.

[heroto]

Thanks for this report. Curious about how fast and how hard you rode. 180km/3.5 hrs = about 50kph. Sound about right? How hard were you accelerating?

[DonTom]

Thanks for this report. Curious about how fast and how hard you rode. 180km/3.5 hrs = about 50kph. Sound about right? How hard were you accelerating?

By his own words, he only averaged 32 MPH.  112 miles divided by 3.5 hours.

That's probably close to where the bike gets its best range on an average.


-Don-  Auburn, CA

[heroto]

the average speed may be 30 mph but was that fairly steady or with a lot of time is faster or slower with lots of acceleration? Hard or gentle acceleration? Hypermiling or burning it up? That’s what I am curious about

[Goetzuwe]

Because of the low average speed.

The area only narrow valleys and mountains 150-600m above sea level, rarely 300m without a curve.
But I only drove side streets with a lot of altitude and very tight curves. Whereby I prefer to go around a tight curve with a 20% gradient than with a 20% downhill.
Although I brake almost exclusively with recuperation (setting to max)
The lot of acceleration after the bends is especially fun with the howling from the gearbox.

I'm looking forward to the next trip.

[most]

Hi Uwe, so I understand you had a nice tour in the Sauerland area (was born there myself). You drove 180km and still had 19% SOC left? So theoretically a range of 214km.

Not bad at all!

hereto wanted to know if after a tight turn you accelerated like hell or if you had more the touristic ride style - are you able to comment on that?

tnxx
most

[octopusenvy]

Kia ora from Aotearoa/NZ...having only recently done some testing on my new 2020 Eva107 (13.4kwh), I was getting similar to LESS range than Morgan on cold,wet,twisty roads. I've also had a good chat with Chris Paz and it's noted that more changes to 'throttle' creates more draw and less efficiency. For those with cruise control, it's a very efficient algorithm and worth using!

In terms of comparisons, I think Morgan and Brandon have done the most testing so far, and importantly for distance tourers, you must compare charging times/rates alongside capacity. Theoretically, a new and older battery bike with equal weighted riders starting at 'A' to reach 'B' at a distance of over 300km would see the older bike arrive first. That is significant in terms of how I ride in NZ. We can go over the numbers as to why, but in a country with ample DC charging points, getting to the distant destination with less time spent charging is a clear advantage.