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[svelectric]

You guys are pretty hardcore. I just pay a premium to live in a very temperate climate. But since we're on the subject of charging issues. I have seen many members talk about the cell balance. Like they know how many millivolts discrepancy the individual cells have.

Can that information be gotten on an Experia without special tools?

Also, now that I've said how pleasant the year round weather is here....this morning's commute through a brief biblical level, end-of-days stormagedden was fine. The Experia handled riding in a downpour, meeting the bow waves of passing trucks,  and riding through significant amounts of standing water at significant speeds with no problems.

The more I ride this bike the more I love it.

I use a bluetooth obd reader and the Hans C. app on my phone to get the balance level in mv's.  Not really a "special" tool, just something I picked up on amazon for a few dollars.

[Pard]

4 F overnight, sunny in the teens today.

Turn on the Rebelle which was at around 70% SOC per main display as of 2 days ago, and now it reads 39% with a message to run the battery down to zero and charge to 100% to align the BMS.

Engineering screen shows 64% SOC with 3.9V on the cells.

First time I ever saw the two SOC indicator sources diverge like that.

Must be due to the cold.

Heating up the battery in the sun and with a hair dryer blowing on it to get it above freezing, then will charge it.

EDIT:

Main display jumped to 43% within minutes of heating up the bike, no charge applied yet, just heat...

[Pard]

Not sure what the temp display indicates by the split number.

Not sure what the SOC indications are read from.

As the battery is being warmed, the TCAH/TCSOC which writes to the the main display SOC indicator, is increasing and getting closer to the BMS SOC value.

Seems the very cold temps are the cause of the wide divergence and that divergence triggers the message to drain and charge to 100%.

After warming up the battery into the green, that divergence and message disappeared.

[Specter]

Hey guys, let me give you some insight here on that.  @Pard
Ive seen the same thing on the track with my bike and you have to be careful about what you see, what you do, as it can raise hell with you if not.

Picture a battery case thats several batteries deep.....   gotit...

Now, batteries run off a chemical reaction, the colder it is, the slower they go, and the less voltage will be at terminals.  Lithium batteries have an added 'issue' of around freezing they want to not really do much at all, they want to about stop producing.

Key take away, lower temp, lower cell voltage.

Now, you let your bike set outside all night, wake up the next morning, it's 26 fucking degrees out !! your bike is covered with frost !!  Your battery percentage is wonky... why?  You have it up when you put her to bed last night.

The battery case is made of ALUMINUM, which can get just as cold as the outside temperature.

Remember now, the batteries are several DEEP.   

So what is happening is, the outer batteries, which are next to the walls of the case are around 28 degrees, they are about ambient temperature.. while the INNER batteries in the core may still be sitting at 60 degrees or so, because they ARE inside and protected thru several layers of other batteries for the heat to get out.

Your BMS may not be measuring the TEMPERATURE of each battery to do it's calculations of state of charge, so it may see only one or two temps, not 162 temps, or however many batteries you have.   It sees the 60 degree battery at 3.6 volts and the 28 degree battery at 3.42 volts NOT knowing the HUGE temperature difference between them, and goes holy shit, this thing is whacked !!  You get gross out of balance errors etc etc, and it may want you to charge it or do other crazy things to try to 'fix' the situation.  That complete re alignment is the BMS saying, under normal circumstances it should have NEVER gotten this bad, something must have changed, let's do a FULL realignment and start from zero to set a new baseline.   Again it does NOT know your have temperature spans of 40 degrees across your battery pack!  Please do NOT do this until you have balanced the battery TEMPERATURE FIRST.

charging / discharging a battery pack with wonky temp excursions can cause problems, because when the batteries now warm back up, the voltage climbs and viola, now they are OVER charged and it wants to burn off the excess.

What I normally do on my bike is Ill run an easy run on the track to get some current flow thru the batteries, that warms them all up and gets the temperaturs a bit closer to each other, PLUS gets it out of the basement shutdown zone.  See a 40 degree difference at say 120 degrees to 80 degrees is not that huge a deal, they are way up in the operating / production range,  that same diff down around freezing is HUGE because you are near the shutdown zone and it has a far more profound affect.

If you Do decide to charge it you may see oddball things as the batteries charge and it tries to 'fix' what really is not a problem and you may see wild swings in charge current from like 0 amp to 24 amps !! as it's trying to 'fix' the voltages.  Have to remember, even though the voltage was a bit low, that battery WAS still charged, so putting more in it's going to shoot up fast, hence the wild amp swings.

Freezing temps do shitty things to batteries, especially lithium.  Before you go doing any panic mode actions or crazy charging schemes, get the batteries warmed up a bit and most importantly EVENLY warmed up so ALL the cells are as close as possible to same temp.

Having a small heater blowing on the bike can help a LOT.  Even though you may still have a bit of a temp excursion across the entire battery, having it at 50 degrees .vs. 30 degrees means a TON.... because freezing means so much to shutting that battery down.

Don't panic, warm the bike up, warm the battery up, .  remember even if it sat overnight in your garage, the temp still may have swung 40 degrees, those inner batteries may NOT have felt that cold yet!  Take her for a spin around the block.  Ride it 5 or 6 miles at an easy speed.  (easy  in my case means NOT trying to go from 0 to 100 in 5 seconds   Get the temps evened out a bit then do your charge if needed.

Aaron

[Pard]

Aaron, excellent analysis.

Thank you.

Indeed, when the battery was brought up to normal operating tempertures, throughout the pack, the numbers aligned.

[jotjotde]

If anyone is interested to know, how regularly the bike checks itself, I have a smart plug installed while on LPR modus (bad weather spell here now).
In the end it’s nearly on daily basis.
The bike draws sometimes about 0.1 kWh, sometimes 0.0.

[Pard]

Interesting!  Thanks @jotjotde

[Specter]

jojo, I have someting similar installed but it's on the entire house. I have it to the point where it can pretty much tell me exactly WHAT turned on and for how long.  It's really amazing the info you can get from those things.  I have had one tell me of impending failures on a refrigerator, which saved me I can't say how many hundreds of dollars in lost food if I didn't catch it.  It's also very educational to see exactly how much something really does consume and use and how often!  and to see how something as simple as changing a gasket on a fridge door can  cut the electrical use down to half.

So, looking at your graph, it does what? comes on for a minute or so, does a quick top off on the battery and then shuts back off?  If so, IMO that's probably topping off that little bit it drew off keeping the 12 volt monitoring stuff alive.

Aaron

[jotjotde]

The device is just a 6 Euro device I got at aliexpress operating on the free-of-charge Tuya app and I originally wanted it to control my outdoor lighting which it does surprisingly well.
Besides the data shown it does not record much more.
We are just a 2 person household, so I did not install anything more sophisticated yet.

The bike seems to have switched to a 2-day check interval now. Three days ago SOC was down to 76%, so I agree that it’s just a few minutes checking and topping off a bit

[chisquare]

@jotjotde Good information. Thanks for sharing. It's the first winter that I have my SS9+RS constantly hooked up the the charger running LPR. So far, it's keeping the 80% SOC perfectly.

[szczur333]

alsmot 8 months in unheated metal garage - not plugged - lost 1% of SoC

[jotjotde]

alsmot 8 months in unheated metal garage - not plugged - lost 1% of SoC

That is astonishing. I would have thought the SOC loss would be higher.

Here's an update of LPR over 26 days so far. My Ribelle stands outside in a carport. We had mostly cold to subfreezing temperatures.
When I put her in LPR mode at 30 % SOC, the bike charged 9.23 kWh (to assumed 80 % SOC).
The bike woke up every 1-2 days, I could not see a regular pattern. Power consumption was between 0.0 and maximum 0.56 kWh. Total consumption over this period was 1.51 kWh.
When I checked yesterday, SOC was 76 %.
Drove the bike down to 20 % and recharged to 80 % consuming 11.27 kWh.
So roughly, the bike lost (consumed) power worth of 10-12 % SOC over 26 days, probably that much because of the regular checks.

[szczur333]

probably even not 1% - bcoz I left it on 1st JUNE 2024 (temperature was about 25*C then) and last time was about 0-5*C

[Specter]

That seems awful high.
When I broke my foot earlier last year I was down for a few months, and didn't put the bike in LPR I just left it there really, and when I came back  months later it was like 86 percent.  I don't remember where I put it in at, but typically my Ribelle Id max charge about 96 percent, hitting 100 once a month for balance.  It may turn itself on and off a few times to check on it's self but that's only for a little bit and the electronics on it don't draw that much power at all.  To be losing kilowatts, hmm, don't think the batteries even self discharge that much.  Interesting.

Was there a temp diff between when you put it in .vs. take it out.

If you start it at like 90 percent and it's at say 90 degrees,  then check it two weeks later and it's 40 degrees, it's going to show a pretty big drop because of the temp difference, especially if the battery has not balanced out temp wise.

id see this at the track.  id be racing and put her to bed with like 90 percent charge, and the batt temp is probably 100 degrees because I ran the hell out of it.  then next morning it's 38 degrees out and the soc is like 74 percent and it wants a balance charge.  Id be like OOF, because i KNOW the damned thing did not lose 15 percent overnight.  Once I ran a session or two and got the temps evened out it settled out and behaved again.

Id make a point of NOT trying to charge it or balance it if it was in that much of a thermal transient, that will really throw a wrench into things and you can seriously whack out your battery balance if you do try to balance it with a big gradient across them.

Aaron