Sv: Elbil-deler/-rester gis bort mot avhenting

[BauDemo]

I completed maintenance charge for my Think yesterday.
The resources available in the wiki were fantastic.
I used the procedure as described here:http://elbilwiki.nipen.no/wiki/Think:Prosedyre_for_vannservice
Thanks to Ken for hand-holding me while finding compatible water filling equipment.
Couple of things that I think would be great if added to the wiki pages:
- point 12 "Ekstra Kjøling/ Varming.." I don't really understand -is it possible for the person performing the maintenance charge to influence in some way - is there any option in the car I missed?
- point 13 "Vedl.lading er ferdig etter 50 Ah overladet..." - to me it sounded like if the 50Ah was reached I have to remove the cable... but my car stopped the charge at 51Ah. So an addition that clarifies if one should proceed to unplug the car once 50Ah have been reached, or not would have been nice.

At the end of the charge my battery pack reached 40C. The water-fill took about 9kg of water. The overcharged since last water-fill was 670Ah. Is 9kg of water good?

On a side note - this was the final test for the water filling function with nikometer. I still need to write some documentation about it, but if you are in need of water fill now, and you have Think EV Monitor (nikometer) you can get the beta version. The version also does the other check functions (for SOC indicator, for maintenance lamp, fans, etc.)

Thanks again to everyone who helped!

[elektrolux]

Congratulations on the Beta vertion off water service on Nicometer. Looking forward to loading this into my Palm. Great job!

Regarding point 12: I find it benefitial to drive the car 20-30 km before starting water maintenence. Because the motor's cooling circuit is connected together with batteries this will heat up the batteries to a good starting point.

Regarding point 13: I find it benefitial to remove charging cable as soon as 25C and falling voltage under fase 2 overcharge is a fact. This usually means after 20+ Ahr overcharge saving the last 30 Ahr overcharge.

That said. I had to use a full 50 Ahr overcharge + 5 Ahr more to reach this creteria on my ovn Think, but that was because I did not take that drive beforehand.

[El rayo]

Excellent, Nikolay!

Point 12: I've never applied additional heating or cooling nor termininated the maintenance charging early. I rely on the information given by Think and that the maintenance charging program is correct.

Point 13: There is a difference between B116 and earlier versions of the BMS program. B116  over charge 40 Ah, then pauses for 25 minutes, then charge for 5 minutes and so on for 72 hours. Water fill can be done at any time within these 72 hours.

The earlier versions over charge 50 Ah, then stops. Disconnect the charging cable at this moment for safety reasons. You need to be present at this moment and start timing, wait 15 minutes and then fill water.

Terminating the overcharge early may have the consequence that all 95 cells are not fully charged, even if the total voltage is dropping. As you can see Robort and I have a little disagreement. Robort is the more experienced one.

That you read 51 Ah over charged is probably due to your program's more correct handling of decimals (i.e. FR-2000 just deletes the decimals). If my memory is correct, you have B111 program.

I think we have concluded that 8 liters/kilograms is the ideal amount. You should reduce the driven distance and /or Ah over charged since last water fill a little next time.

[Lynet]

Gratulerer Nikolay  

Gleder meg virkelig til å teste dette, jeg trenger snart en vannfylling.
Jeg stopper serviceladingen selv på ca 38Ah overlading. Hvis man ser på vedlagte graf kunne jeg stoppet på ca 28Ah. Da har spenningen falt, og tempen passerer 25 grader.
Da er grafen oppdatert.
Det er noe smårusk de første minuttene, det er fordi jeg gikk over på laderen og logget den noen minutter for så å gå tilbake til BMS.

[Ken]

Fantastic news and a great New Years present for us with Nikometer.

A few comments on the points thay you raised. My point of view on overcharging falls between the two mentioned. I feel that a sinking voltage on average may mean that most modules are fully charged but a few may have a way to go. We talk about averages here although those of us with PakTrakr kan follow the progress of every module. I have seen that some of these take a long time to reach a falling voltage while most modules  fall to nearly 7 volts again.
My Think with B111 didn``t stop the maintenance charge after 50Ah and the charge had to be terminated manually. I was a bit hasty perhaps.
You were a bit lucky with the charging because the charger stops at 40 degrees. Charging resumes after the pack cools down some.

New Years resolution- get some isulation and heating in my garage!

[BauDemo]

Thanks for the answers... I am still confused though.
What is the reason for the maintenance charge?
Is it to get the battery pack to certain temperature (what temperature?) so we can do water fill?
Or is it to equalize the pack?
If I am to stop maintenance charge at say 36Ah what is the criteria that I should use?

[Ken]

The primary purpose of the maintenance charge is to get the electrolyte to the highest possible level  before water filling. This minimises the possibility of overfilling the modules. Elektrolyte is "squeezed" out of the plates during the overcharging phase. We follow voltage and temperature to ascertain the condition of the module during the overcharging prosess. Allow the total voltage to fall significantly before terminating the charge. We would generally try to overcharge for 30Ah if high temperature is an issue .
If the charge is activated in good time and there is adequate electrolyte level in the modules, the dangers involved in overcharging are minimal and the full overcharge can be allowed.

Maintenance charge is also recommended if a vehicle has stood idle for a long period to balance the pack.

[El rayo]

Thanks for the answers... I am still confused though.
What is the reason for the maintenance charge?
Is it to get the battery pack to certain temperature (what temperature?) so we can do water fill?
Or is it to equalize the pack?

In addition to getting all the cells to gas so that the electrolyte level is at it's max the maintenence charge equalizes the pack.
Recommended reading: http://www.e-m-w.com/manuals/SAFT_Stm5-100mre.ChargeMode.pdf
and http://www.e-m-w.com/manuals/SAFT_Tech_manual.pdf

[El rayo]

Maintenance charge is also recommended if a vehicle has stood idle for a long period to balance the pack.

When a vehicle has stood idle for one month or more Saft recommends an initialisation charge followed by water filling.
This is different from initiate new battery in that the BMS' Ah counter is not reset to 100, but keeps the actual capacity number that the BMS has accuired over time.

[BauDemo]

Very interesting reading...
I have couple of more questions:
- if you start the car (key is on) and connect to the BMS and
activate maintenance charge, then you still keep the car on and not plugged
for charging. Now you connect to the charger (with FR2000) - does the
charger report maintenance charging as ON?
- if you activate maintenance charge and then plug the car, then unplug the
car after say 2Ah charge, is the maintenace charge canceled?
- if you activate maintenance charge when the SOC of say 70%, and start
charging, then connect to the charger with the FR2000, does the FR2000
report that this is maintenace charge directly or start after 100% SOC
is reached?
nikometer is not reporting correctly the state, and I need some help figuring this out...

[elektrolux]

Very interesting reading...
I have couple of more questions:
Answers I can help with in Bold
- if you start the car (key is on) and connect to the BMS and
activate maintenance charge, then you still keep the car on and not plugged
for charging. Now you connect to the charger (with FR2000) - does the
charger report maintenance charging as ON?
?
- if you activate maintenance charge and then plug the car, then unplug the
car after say 2Ah charge, is the maintenace charge canceled?
Yes,  but if you wait with plugging in this also means people can drive to apropriate place to activate maintenence charge, drive home, and then start maintenence charge.
- if you activate maintenance charge when the SOC of say 70%, and start
charging, then connect to the charger with the FR2000, does the FR2000
report that this is maintenace charge directly or start after 100% SOC
is reached?
?
nikometer is not reporting correctly the state, and I need some help figuring this out...

[BauDemo]

Thanks elektrolux!
I am not sure I understand:

but if you wait with plugging in this also means people can drive to apropriate place to activate maintenence charge, drive home, and then start maintenence charge.

Is this the way it works now?
I don't plan to reprogram how the cars bms or charger work, I am interested how does it work now.

[Ken]

To try to help you with your problems I will reiterate the standard proceedure for activation of the maintenance charge. Once one has activated the charge by coming out of the menu, turn off the ignition and plug in the charger. The charge will only begin when phase two charging is reached. The battery current will be higher than the normal 5A.
The charge will be terminated when the ignition is activated if it hasn``t finished by itself. The FR 2000 does not have to be plugged in during the charge.
What I don``t know:
How long the charge will be activated if the ignition remains on.
If one can in fact drive to a point B to start the charge.
If it makes a difference if the key is turned to the start stroke.
If the charge terminates after the charging plug is removed although the charger is turned on and off by the BMS when the battery temperature is over 40 degrees during the charge.
I will have to get hold of the FR2000 and experiment.

[BauDemo]

now another question - when is the normal charge done?
I thought that the charge is ready when the light stops flashing... but today while experimenting I noticed that the charge light on the dash has stopped flashing and was constantly on. I thought that the charge was ready, but noticed that the charger continued to put 5A in the battery. I did not have time to wait on it...
So, what is the deal here? When is the charge ready?

[El rayo]

I've noticed the same - constant charge light and mains current still about 5 A. I often interrupt charging  ( some times opportunity charging).

My theory is that the charge light becomes constant when the normal charge cycle - 100 % soc plus 15% (?) of the last charge - is completed. If there is a back log of over charged Ah due to previous interrupted charges, the phase 2 charge will continue at about 5 A battery current.