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[ESokoloff]

By this I’m referring to letting the onboard charger go to 100% and then shut off thus insuring cell balance has occurred.

Back in July of this year my 2016 DSR battery was changed under warranty.
I decided to try and keep the SOC of the new battery in “the sweet spot” so have limited it to around 80% max.
I now have 4,563 miles with only 3 charge cycles (1,110 miles on the last one) yet presently  @ 83% the cell balance is 2-3 mv.

I’m thinking letting the charger go to 100% so cell balance can happen is not necessary or I’m I missing something?

[DonTom]

I’m thinking letting the charger go to 100% so cell balance can happen is not necessary or I’m I missing something?

You should let it get to 100% once in a while. It's  best if you ride it after and not leave it for weeks at 100%.  Most of the time you want to keep the battery at around 60% SOC when not using it much.


-Don-  Reno, NV

[enaef]

I don't know about the DSR.
Regarding my SR/F I was told, that each time i set a charge target the balancing happens. It was the answer I expected, as the charge curve goes down towards the end of the charging despite the charge target.
I have asked my dealer which (as far as I know) has asked Zero.

However: I don't know if that's true also for a DSR.

What is the charging behaviour towards the end of a charge with a goal <100%? That might give a hint.

[JaimeC]

The Gen2 bikes don't have an automatic "Charge Target" other than 100%.  Based on what I see when I'm on a Chargepoint L2 station, after 80% it drops from 6kW to 3kW.  Around 90% it drops again steadily downward till it hits 100% and 0kW.  These are estimates.

[ESokoloff]

I’m thinking letting the charger go to 100% so cell balance can happen is not necessary or I’m I missing something?

You should let it get to 100% once in a while. It's  best if you ride it after and not leave it for weeks at 100%.  Most of the time you want to keep the battery at around 60% SOC when not using it much.


-Don-  Reno, NV

Sparky is my daily commuter so it’s max rest time is only three days straight.
My dilemma is finding the Goldilocks of max SOC & don’t want to jeopardize cell balance in the process.

[ESokoloff]

I don't know about the DSR.
Regarding my SR/F I was told, that each time i set a charge target the balancing happens. It was the answer I expected, as the charge curve goes down towards the end of the charging despite the charge target.
I have asked my dealer which (as far as I know) has asked Zero.

However: I don't know if that's true also for a DSR.

What is the charging behaviour towards the end of a charge with a goal <100%? That might give a hint.

As explained by JamieC, different animals.
This is why a separate section for the next/present architecture would be helpful (to reduce confusion).

Thanks anyway tho. 

[ESokoloff]

The Gen2 bikes don't have an automatic "Charge Target" other than 100%.  Based on what I see when I'm on a Chargepoint L2 station, after 80% it drops from 6kW to 3kW.  Around 90% it drops again steadily downward till it hits 100% and 0kW.  These are estimates.

Your post got me to thinking & Morgan's response to another question confirms it.
I need to chart cell balance at different SOC levels to see where balance becomes an issue. 

I will assume that cell balance at a given SOC will change as the battery ages & thus cell balance at end of charge (sub 100%) should be monitored.

[DerKrawallkeks]

I’m thinking letting the charger go to 100% so cell balance can happen is not necessary or I’m I missing something?

You should let it get to 100% once in a while. It's  best if you ride it after and not leave it for weeks at 100%.  Most of the time you want to keep the battery at around 60% SOC when not using it much.


-Don-  Reno, NV

@DonTom Keeping the battery at 60% is a bad idea I think. This is because according to the papers you find about battery aging, there is a critical threshold around roughly 55%, above which the aging process is much faster.
Therefore, it does not make sense to keep a battery just slightly above that. I would recommend keeping it at 50 or below, rather than 60.

[JaimeC]

@DonTom Keeping the battery at 60% is a bad idea I think. This is because according to the papers you find about battery aging, there is a critical threshold around roughly 55%, above which the aging process is much faster.
Therefore, it does not make sense to keep a battery just slightly above that. I would recommend keeping it at 50 or below, rather than 60.

Now you're splitting hairs.  Zero (based on data from Farasis) recommends for long term storage to keep the battery between 60% to 30%.  But if you're riding the bike regularly there's no reason not to keep it above that threshold.  If you read some of the threads in here, allowing the battery to sit at 20% or less for prolonged periods of time will result in PERMANENT damage to the battery.

In other words, state of charge shouldn't be a concern for a motorcycle ridden regularly.  "Just ride it."

[princec]

Also, "much" faster I think in this case might mean shortening the battery's life by a few weeks, against its total expected lifespan of many, many years.

Cas

[NEW2elec]

Once again I'll take the financial angle.  For the Gen 2 bikes Zero says charge the bike to 100% and unplug it.
Since only Zero and not any battery expert or battery paper author is going to give you a free replacement battery under warranty.
I suggest following their recommendations.

[JaimeC]

But the less time spent at 100% the better.  Bringing it to 100% just before an anticipated long leg of a ride is fine.  You should also bring it to 100% at least once a month to allow the cells to balance.  When I'm actively on a ride, I start at 100%, but when I stop at charging stations I charge to 80% just because the charge rate starts to taper off after that and 80% is more than enough charge to get me to another charging station where I live.

My 2016 S came with directions to leave the bike plugged in if you weren't riding it.  At that point, Zero warrantied the battery for five years, or 100,000 miles (whichever came first).  After their new guide lines came out, the warranty changed to five years, unlimited miles.  I don't know about you, but putting 20,000 miles a year on ANY motorcycle (let alone an electric one) is a stretch... I managed that once or twice with my ICE bikes... but as far as the Zero is concerned?  Both warranties are basically the same thing.  I don't keep my Zero plugged in more as a function of not wasting electricity more than preserving the battery life.

[DonTom]

@DonTom Keeping the battery at 60% is a bad idea I think. This is because according to the papers you find about battery aging, there is a critical threshold around roughly 55%, above which the aging process is much faster.
Therefore, it does not make sense to keep a battery just slightly above that. I would recommend keeping it at 50 or below, rather than 60.

Tell that to Zero, as they recommend to store the bike at 60% SOC.


"For planned long-term storage (more than 30 days), we recommend draining the power pack to a ~60% state of charge, and leaving the motorcycle unplugged.[/size]Once again, the power pack will drain extremely slowly over time. Check the state of charge (SoC) at least monthly, and charge it back up to 60% if it has dropped below 30%. When you’re ready to take your motorcycle out of storage to ride it again, plug it in for at least 24 hours to ensure optimal cell balance is restored.
[/size]Warning: Never store your motorcycle at a state of charge of less than 30%. Leaving the power pack discharged below this level for a prolonged period could damage the power pack and void the warranty.[/i]
[/size]This forum software has a lot of bugs![/i]
[/size][/i]
[/size]-Don-  Auburn, CA[/i]

[ESokoloff]

Once again I'll take the financial angle.  For the Gen 2 bikes Zero says charge the bike to 100% and unplug it.
Since only Zero and not any battery expert or battery paper author is going to give you a free replacement battery under warranty.
I suggest following their recommendations.

I did that on the original battery yet it failed (less then 80% capacity) so don’t want a reoccurrence.

Do a google search on optimized Li-Ion battery SOC & you come up with many recommendations for 80 max & 30 or 40 min.
Zero doesn't list a recommended running minimum level.

I only need about 30-40% for each leg of my commute. 
Why stress the battery by charging it to 100% & then drain it to sub 30%?

I’m going to plug in on both ends of my commute & limit charge to 75% -+ 5 & try to keep up on cell balance.

[TheRan]

You're not stressing it by charging to 100% if you're actually going to ride the bike after, just don't store the bike at 100%. I would say you're going to do more damage (still not much) going from 75% to 35-45% with an unbalanced battery.