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[BrianTRice@gmail.com]

Battery overheating is a bigger deal for charging than it is for the motor. Last summer I rode my Eva to Charlotte, NC when the temps were in the low 90s. On the second DCFC it started to taper earlier than I had seen it before. When I took off I noticed the battery icon was yellow and it stayed that way for 15-20 minutes of riding but no reduction in power. On the third and last DCFC it started to taper even earlier and the battery icon styed yellow all the way home, about an hour ride. Again, never noticed any decrease in available power.

That's interesting. This is one thing about desire for high-C-rate DCFC - it'll push us right up against battery cooling system limits. Zero is sticking with 1C across the SoC range although there've been murmurs (CHAdeMO support certainly seemed to get there) of exceeding 1C in the mid-range charge states.

Do you know what the full/nominal C rate is for DCFC on your bike (or kW which we can get C-rate from roughly)?

[pacificcricket]

That's interesting. This is one thing about desire for high-C-rate DCFC - it'll push us right up against battery cooling system limits. Zero is sticking with 1C across the SoC range although there've been murmurs (CHAdeMO support certainly seemed to get there) of exceeding 1C in the mid-range charge states.

Do you know what the full/nominal C rate is for DCFC on your bike (or kW which we can get C-rate from roughly)?

If you look at the PDF I linked a couple of posts ago (likely the same link as in Unofficial Manual), the max charge current specified by the manufacturer is 25A. That is for 25Ah cell... only 1C. I couldn't find datasheets for later 27Ah and newest 32Ah cells made by Farasis, but it's very likely they haven't deviated from that rating given the same chemistry of the cell (NMC). So really with that stuff you're stuck with full charge in a bit under 1 hour, and not a minute faster. Does the cell warm up significantly charging at 1C ? There is probably a testing report available somewhere.

[BrianTRice@gmail.com]

That's interesting. This is one thing about desire for high-C-rate DCFC - it'll push us right up against battery cooling system limits. Zero is sticking with 1C across the SoC range although there've been murmurs (CHAdeMO support certainly seemed to get there) of exceeding 1C in the mid-range charge states.

Do you know what the full/nominal C rate is for DCFC on your bike (or kW which we can get C-rate from roughly)?

If you look at the PDF I linked a couple of posts ago (likely the same link as in Unofficial Manual), the max charge current specified by the manufacturer is 25A. That is for 25Ah cell... only 1C. I couldn't find datasheets for later 27Ah and newest 32Ah cells made by Farasis, but it's very likely they haven't deviated from that rating given the same chemistry of the cell (NMC). So really with that stuff you're stuck with full charge in a bit under 1 hour, and not a minute faster. Does the cell warm up significantly charging at 1C ? There is probably a testing report available somewhere.

Let’s be clear that the C-rate is current and 1C for a 25Ah cell is 25A and for a 32Ah cell is 32A.

I’ve been given and independently confirmed reason to believe that technically >1C can be supported if the external charger is in live communication with the BMS to ramp charging rates if there is any doubt of a temperature trend outside normal. And also that this C-rate limit depends on dynamic conditions and also only within the middle band. Essentially there is a multivariate manifold within which charging effects can be predicted and a charger if sufficiently well programmed with internal safeguards and robust failsafes with live sensor readings, could exceed 1C while protecting the cells lifetimes.

Notably, this is so highly contingent on complex factors that Zero reasonably does not support it.

Zero programs the BMS to operate the contactor at or below the 1C rate but Zero can change that if they can justify with Farasis that the cell parameters could be assured.

Note that DigiNow 2.5 is leveraging a status message from each BMS carrying the dynamic C-rate limit and dials the charging output to fit within it.

PS opening the contactor at high C rates would be bad, so this is all speculative. The point of battery stacking is to bring DCFC within the 1C rate.

[pacificcricket]

I’ve been given and independently confirmed reason to believe that technically >1C can be supported if the external charger is

Unless you got the word from the manufacturer of the cell, that's basically "I can do whatever at my own risk."

[ultrarnr]

BrianTRice, I have no idea what the full/nominal C rate is for DCFC for the Eva. The battery does have air vents that go through the center of the battery, you can see them directly behind the front wheel. I am sure it helps but there is still that point when it is really warm out that they aren't enough.On one hand it would be nice to have liquid cooling for the battery but this would also add cost and weight to the bike. It is also only a problem when the air temp is really warm so for most multi-DCFC trips it isn't an issue. Last July when I went out to western NC I never had a problem. Even riding the Blue Ridge Parkway where I rode over 350 miles in one day and only used CCS charging it was never an issue.

[BrianTRice@gmail.com]

I’ve been given and independently confirmed reason to believe that technically >1C can be supported if the external charger is

Unless you got the word from the manufacturer of the cell, that's basically "I can do whatever at my own risk."

Even if I got word from the manufacturer! The point is to turn the risk envelope into a proper engineering table or set of equations and observation-based safeguards (and to failsafe when the observations are unavailable).

BrianTRice, I have no idea what the full/nominal C rate is for DCFC for the Eva.

I'm asking what rate do you normally charge at that was then ramped down. In kW or A. The C-rate of that charge is just taking the kW or A and dividing by kWh or Ah capacity of the battery. The "rate" is not the "rating".

[pacificcricket]

Even if I got word from the manufacturer! The point is to turn the risk envelope into a proper engineering table or set of equations and observation-based safeguards (and to failsafe when the observations are unavailable).

What you're talking about is more science than engineering, which manufacturer is in the prime position to do. You could re-verify their findings, but you'd have to employ similar methods, which you're likely not in a position to do. So whenever you exceed the cell's specification, you do so at your own risk, even if you think you're backed by a few engineering tests.

[BrianTRice@gmail.com]

Even if I got word from the manufacturer! The point is to turn the risk envelope into a proper engineering table or set of equations and observation-based safeguards (and to failsafe when the observations are unavailable).

What you're talking about is more science than engineering, which manufacturer is in the prime position to do. You could re-verify their findings, but you'd have to employ similar methods, which you're likely not in a position to do. So whenever you exceed the cell's specification, you do so at your own risk, even if you think you're backed by a few engineering tests.

Let's be clear that "you" in this case is hypothetical, probably the reader of this forum who thinks they can DIY fast-charging. I'm not doing this, and I'm purposefully vague about my sources for many reasons.

[David S]

Anyone have a guess if the Givi top cases that most people use on their SR's will be compatible with the SRF?

[Richard230]

Anyone have a guess if the Givi top cases that most people use on their SR's will be compatible with the SRF?

Does the SR/F have a rear rack?  If one is available, I would think that a Givi case would likely fit on the rack.  But has Zero announced a line of accessories for the SR/F yet? I can't recall seeing any accessories yet. 

[BrianTRice@gmail.com]

Anyone have a guess if the Givi top cases that most people use on their SR's will be compatible with the SRF?

Zero's Givi solution is a top rack with one of Givi's universal plates bolted to it. I'm sure there will be something very similar.

I saw one reference to Shad luggage probably for the side cases, but if Shad fits, Givi will fit.

[grmarks]

There are a lot of owners with a rear rack, so I would expect they catered for one in the design. It would be very silly if they didn't.

[NEW2elec]

David S good question.  I looked at a YT video and they didn't show a clear close up but I could just make out a side bolt near the rear seat.
The silver side parts complicate things a bit.  They have long open spaces that "may" help support a rack made just for this bike hard to tell.
The other thing I noticed was the new dash is much wider than the handle bar attachment bolts and would nee a new windscreen design as well.

[NEW2elec]

Just look at em a whole pack like a very quite biker gang.






P.S.  I just saw it.  The teal tank shows it best.  The Zero logo is an eye and the silver front piece is a fang!  It's a striking snake head!  That's just awesome!

[NEW2elec]

And here he confirms belts changes without removing the swing arm.