BMU Cell voltage smoothing

[t3lmo]

The procedure you are looking for is not the 'smoothing' one but the 'Capacity and Control Reset', and its the same used on i-MiEV battery pack to reset the history of the Control information for the BMU module.

RESET ESTIMATED INFORMATION AND CONTROL INFORMATION OF MAIN BATTERY CAPACITY
If replacing the main battery, reset the main battery capacity information and the control information.
note If replacing the BMU and the main battery at the same time, you do not have to do this procedure.
--------------------------------------------------------------------------------
1.Connect the M.U.T.-III to the diagnosis connector with the electric motor switch in the "LOCK" (OFF)position.
2.Turn the electric motor switch to the ON position.
3.From the System select Screen of the M.U.T.-III, select the "BMU".
4.Select the "Special Function" from the BMU screen.
5.Select the "Reset" from the Special Function screen
6.Select the "Battery capacity estimated info" from the Reset screen, and reset.
7.After the estimated information of the main battery capacity is reset, select "Control information" from the Reset Screen to reset.
8.Put the power switch in the LOCK (OFF) position.
9.After the reset of the BMU control information, check the battery current capacity according to the following procedures:
(1) After 10 seconds elapsed from the previous process, turn on the power switch.
(2) Select the "STV (Scan Tool Viewer)" from the M.U.T.-III start screen.
(3) Select the "System Select" from the fault STV top menu screen.
(4) Select the "BMU" from the system select screen.
(5) Select the "Service Data" from the BMU screen.
(6) Check the BMU service data, item No. 23: Battery current capacity.
(7) If the value, item No. 23: Battery current capacity, satisfies 45.0 - 48.0 Ah, go to the step 10. If not, start from step 4 to do the reset of the control information.
10.Turn the electric motor switch to the "LOCK" (OFF) position to disconnect the M.U.T.-III.

 

[Bert]

Interesting. Please post whether the "new" capacity holds after a month or 2, as other users who have had this procedure done say it is short-lived.

I'm very interested in what your charging style and EV driving style has been eg fast chargers, always charging to 100%, drive mostly EV or lots of ICE km?

I'm still testing the heck out of this new battery at the moment and documenting everything on video. We don't have the fast charge socket in our cars here in Down Under, so it has never seen a faster charge than 16A.
I usually drive 30km a day and charge it to full from 1am in the night, so it's ready in the morning. Using the standard 10A EVSE supplied with the car... Usually 7 days a week unless I'm not using the car on the weekend it does not get a charge the night before and keeps sitting on 50%SOC for the day.

I don't like to have it sit on 100% SOC for too long. Some of you are saying there is a top buffer which is not been used. Well, I could not find any evidence supporting that, as I can now charge my car with almost 10kWh from 'empty' 30%SOC to 'full' 100%SOC. Also, if there is a buffer, the charging speed would not slow down at the end but just stop when reaching the threshold? And lastly, there is no regen with a full battery until it reaches 92%SOC. If there is a top buffer, it would need to simulate a full battery, otherwise it would just regen... just my obervations and maybe another story/video worth...

Thanks guys.

 

[HHL]

Well, the "top buffer" could be "enabled" by simply increasing the charging voltage slightly... It would still taper off towards the end of the charge but you would end up with more energy to use without lowering the cut-off at the other end.
It would be useful to know if anyone who had that procedure done has been able to measure more than 4.1V/cell after a full charge.

 

[anko]

The procedure you are looking for is not the 'smoothing' one but the 'Capacity and Control Reset', and its the same used on i-MiEV battery pack to reset the history of the Control information for the BMU module.

You write this in response to who / what?

The procedure you describe IMHO is pure administrative (like resetting your MPG number) and should take no more than 2 minutes. The procedure performed against my car actually encompasses charging and discharging the battery at a very low pace and takes several (12?) hours to complete.

 

[elm70]

Interesting. Please post whether the "new" capacity holds after a month or 2, as other users who have had this procedure done say it is short-lived.

I'm very interested in what your charging style and EV driving style has been eg fast chargers, always charging to 100%, drive mostly EV or lots of ICE km?

I'm still testing the heck out of this new battery at the moment and documenting everything on video. We don't have the fast charge socket in our cars here in Down Under, so it has never seen a faster charge than 16A.
I usually drive 30km a day and charge it to full from 1am in the night, so it's ready in the morning. Using the standard 10A EVSE supplied with the car... Usually 7 days a week unless I'm not using the car on the weekend it does not get a charge the night before and keeps sitting on 50%SOC for the day.

I don't like to have it sit on 100% SOC for too long. Some of you are saying there is a top buffer which is not been used. Well, I could not find any evidence supporting that, as I can now charge my car with almost 10kWh from 'empty' 30%SOC to 'full' 100%SOC. Also, if there is a buffer, the charging speed would not slow down at the end but just stop when reaching the threshold? And lastly, there is no regen with a full battery until it reaches 92%SOC. If there is a top buffer, it would need to simulate a full battery, otherwise it would just regen... just my obervations and maybe another story/video worth...

Thanks guys.

How do you get this 10kwh ?

From MMCS display ... or from a wall socket with power meter inside ?

From MMCS .. I think my record has been just 9kw .. from 26% charge .. so with lowest charge in the battery when the car is used for low power in the last km with "empty" battery

 

[zzcoopej]

I usually drive 30km a day and charge it to full from 1am in the night, so it's ready in the morning. Using the standard 10A EVSE supplied with the car

Ok, do you have a cutoff time, or just let it run until 9am or so? I start charging at 10pm and off at 7am. By not starting till 1am, the cell balancing and other BMU functions could still be happening around 7-8am I would think. So although you hop in the PHEV and see a full battery, the BMU might not get a chance to finish its routines and update accurate stats? Time will tell whether the dealer reset results in a permanent increase. If your increase is permanent and big (unlike Anko whose real degradation is probably from towing his van, so can't be magically reinstated) I then the only plausible explanation I can come up with is cutting short the charge (or a faulty battery).

 

[HHL]

I usually drive 30km a day and charge it to full from 1am in the night, so it's ready in the morning. Using the standard 10A EVSE supplied with the car

Ok, do you have a cutoff time, or just let it run until 9am or so? I start charging at 10pm and off at 7am. By not starting till 1am, the cell balancing and other BMU functions could still be happening around 7-8am I would think. So although you hop in the PHEV and see a full battery, the BMU might not get a chance to finish its routines and update accurate stats? Time will tell whether the dealer reset results in a permanent increase. If your increase is permanent and big (unlike Anko whose real degradation is probably from towing his van, so can't be magically reinstated) I then the only plausible explanation I can come up with is cutting short the charge (or a faulty battery).

I run my charging lead (the one with the 15A plug) through a WEMO Insight switch as a timer and charge meter. I have it set to start at midnight and the longest the charger in the car has ever run is 5:15 hrs. It charges at a maximum of 2.2kW and it tapers off in the last half hour or so. The WEMO switch stops recording when usage drops below 5W, the idle power once the battery is full is about 2W. The maximum I ever had go into the battery was 9.6kW quite a while ago, more recently it was 9.3kW (EVBATMON reports a battery condition 88.16, 33.5Ah, when I bought the car 2 years ago it was 91.7). The MMCS usually reads 200Wh less than the WEMO on a full charge.
Using the 10A charging lead would probably result in a charging time of over 6 hours, but the charge and balancing should be finished by 8am on a 1am start.

 

[HHL]

This article (towards the end) would explain what happens in "cell smoothing".
The article also says that even current BMS can be out as much as 15% in their battery capacity estimate.

http://batteryuniversity.com/learn/article/electric_vehicle_ev

 

[jaapv]

I usually drive 30km a day and charge it to full from 1am in the night, so it's ready in the morning. Using the standard 10A EVSE supplied with the car

Ok, do you have a cutoff time, or just let it run until 9am or so? I start charging at 10pm and off at 7am. By not starting till 1am, the cell balancing and other BMU functions could still be happening around 7-8am I would think. So although you hop in the PHEV and see a full battery, the BMU might not get a chance to finish its routines and update accurate stats? Time will tell whether the dealer reset results in a permanent increase. If your increase is permanent and big (unlike Anko whose real degradation is probably from towing his van, so can't be magically reinstated) I then the only plausible explanation I can come up with is cutting short the charge (or a faulty battery).

I run my charging lead (the one with the 15A plug) through a WEMO Insight switch as a timer and charge meter. I have it set to start at midnight and the longest the charger in the car has ever run is 5:15 hrs. It charges at a maximum of 2.2kW and it tapers off in the last half hour or so. The WEMO switch stops recording when usage drops below 5W, the idle power once the battery is full is about 2W. The maximum I ever had go into the battery was 9.6kW quite a while ago, more recently it was 9.3kW (EVBATMON reports a battery condition 88.16, 33.5Ah, when I bought the car 2 years ago it was 91.7). The MMCS usually reads 200Wh less than the WEMO on a full charge.
Using the 10A charging lead would probably result in a charging time of over 6 hours, but the charge and balancing should be finished by 8am on a 1am start.

Well, in practice it takes about 4.5 hours. Are you on 220 V instead 0f 240 V?

 

[HHL]

Well, in practice it takes about 4.5 hours. Are you on 220 V instead 0f 240 V?

Usually it takes just under 5 hours, we have 240V mains here, but that really should make no difference as the 15A plug charging cable will charge at about 2.2kW no matter what the input is. The cable with the 10A plug will charge at 1.8kW, so it takes quite a bit longer.

 

[anko]

, we have 240V mains here, but that really should make no difference as the 15A plug charging cable will charge at about 2.2kW no matter what the input is. The cable with the 10A plug will charge at 1.8kW, so it takes quite a bit longer.

Don't think that this is correct. At least not as long as you have not hit the max watts of the OnBoardCharger (which is known to be at least 3300).

Per the protocol implemented, the brick in the charge cable (or the wall box) tells the car what the maximum current is that can be drawn from the mains. The actual watts depend on the voltage. More voltage means more watts.

In theory, Mitsubishi could have implemented something that took the allowed max current as specified by the pilot signal, multiplied the value by (e.g.) 230 and divided it by the actual voltage. And treat that derived number as if it was the specified max current. If that were the case, the actual watts would no longer depend on the actual voltage. But it would be very dangerous, as an under-voltage would result in an over-current. Cannot imagine they would have done that. Also, Vtechtuning has built a device that pumps out 260 volt and has increased charge rate with a few percent that way. Not sure if I would like to be a beta tester for such device, but that is a different story ;-) )

For sure the cable with a 10A plug wil charger slower than the one with a 15A plug, because the first specified a lower max current than the second.

 

[Bert]

How do you get this 10kwh ?

From MMCS display ... or from a wall socket with power meter inside ?

From MMCS .. I think my record has been just 9kw .. from 26% charge .. so with lowest charge in the battery when the car is used for low power in the last km with "empty" battery

I've got a meter in between powerpoint and EVSE, which showed me 10.05kWh the next morning. The MMCS has shown the same when I calculated it back.

 

[Bert]

Ok, do you have a cutoff time, or just let it run until 9am or so? I start charging at 10pm and off at 7am. By not starting till 1am, the cell balancing and other BMU functions could still be happening around 7-8am I would think. So although you hop in the PHEV and see a full battery, the BMU might not get a chance to finish its routines and update accurate stats? Time will tell whether the dealer reset results in a permanent increase. If your increase is permanent and big (unlike Anko whose real degradation is probably from towing his van, so can't be magically reinstated) I then the only plausible explanation I can come up with is cutting short the charge (or a faulty battery).

I plugin at 5:30pm but the timer inside the garage starts the charging at 1am (the car has not charging timer itself so...). I leave it plugged in until I go at 7:30am in the morning. So, if you calculate max of 5h for charging from absolute empty to 100% SOC it is ready charged by 6am every morning, way before I unplug it and leave...

 

[Bert]

I run my charging lead (the one with the 15A plug) through a WEMO Insight switch as a timer and charge meter. I have it set to start at midnight and the longest the charger in the car has ever run is 5:15 hrs. It charges at a maximum of 2.2kW and it tapers off in the last half hour or so. The WEMO switch stops recording when usage drops below 5W, the idle power once the battery is full is about 2W. The maximum I ever had go into the battery was 9.6kW quite a while ago, more recently it was 9.3kW (EVBATMON reports a battery condition 88.16, 33.5Ah, when I bought the car 2 years ago it was 91.7). The MMCS usually reads 200Wh less than the WEMO on a full charge.
Using the 10A charging lead would probably result in a charging time of over 6 hours, but the charge and balancing should be finished by 8am on a 1am start.

I cut off the 15A plug and put a 10A on the standard EVSE which came with the car. Just too annoying to find a 15A socket all the time. The EVSE limits the car's charge to 10A anyways. This is all if you're in Australia, guys!!!
It usually charges with 2.4kW unless I'm running the whole show on a 20m extension cable or so while on vacation. It does not matter what kind of lead you're using though. The standard EVSE does not deliver more than 10A to the car so it makes almost not difference to charging time. I'll do a video in the near future about this whole charging thingy...

The 200Wh less could be loss due to the charger (but it seems very little to me). Maybe its just tolerance between different methods of device/measuring.

 

[Bert]

Usually it takes just under 5 hours, we have 240V mains here, but that really should make no difference as the 15A plug charging cable will charge at about 2.2kW no matter what the input is. The cable with the 10A plug will charge at 1.8kW, so it takes quite a bit longer.

You have one EVSE with 15A plug and one with 10A plug?

 

[Bert]

, we have 240V mains here, but that really should make no difference as the 15A plug charging cable will charge at about 2.2kW no matter what the input is. The cable with the 10A plug will charge at 1.8kW, so it takes quite a bit longer.

Don't think that this is correct. At least not as long as you have not hit the max watts of the OnBoardCharger (which is known to be at least 3300).

That cannot be correct unless HHL is using a different EVSE which tells the car's charger how much current it can take. You have outlined that below just fine:

Per the protocol implemented, the brick in the charge cable (or the wall box) tells the car what the maximum current is that can be drawn from the mains. The actual watts depend on the voltage. More voltage means more watts.

In theory, Mitsubishi could have implemented something that took the allowed max current as specified by the pilot signal, multiplied the value by (e.g.) 230 and divided it by the actual voltage. And treat that derived number as if it was the specified max current. If that were the case, the actual watts would no longer depend on the actual voltage. But it would be very dangerous, as an under-voltage would result in an over-current. Cannot imagine they would have done that. Also, Vtechtuning has built a device that pumps out 260 volt and has increased charge rate with a few percent that way. Not sure if I would like to be a beta tester for such device, but that is a different story ;-) )

For sure the cable with a 10A plug wil charger slower than the one with a 15A plug, because the first specified a lower max current than the second.

 

[anko]

That cannot be correct unless HHL is using a different EVSE which tells the car's charger how much current it can take. You have outlined that below just fine:

You got me confused. What exactly cannot be correct? What HHL said? Or what I said?

 

[HHL]

Usually it takes just under 5 hours, we have 240V mains here, but that really should make no difference as the 15A plug charging cable will charge at about 2.2kW no matter what the input is. The cable with the 10A plug will charge at 1.8kW, so it takes quite a bit longer.

You have one EVSE with 15A plug and one with 10A plug?

The vehicles sold here initially were supplied with an EVSE that had a 15A plug, the actual maximum current draw of this device was set at 10A!
Later, Mitsubishi supplied an EVSE witha 10A plug and this one allowed a maximum draw of 8A, so it takes longer to charge.
The reason they would have done this would be because most people do not have 15A sockets and the added expense of installing one deterred some buyers, so they opted to supply the 10A plug EVSE.......

 

[Bert]

That cannot be correct unless HHL is using a different EVSE which tells the car's charger how much current it can take. You have outlined that below just fine:

You got me confused. What exactly cannot be correct? What HHL said? Or what I said?

What HHL said, sorry...

 

[Bert]

The vehicles sold here initially were supplied with an EVSE that had a 15A plug, the actual maximum current draw of this device was set at 10A!
Later, Mitsubishi supplied an EVSE witha 10A plug and this one allowed a maximum draw of 8A, so it takes longer to charge.
The reason they would have done this would be because most people do not have 15A sockets and the added expense of installing one deterred some buyers, so they opted to supply the 10A plug EVSE.......

OK, that's new to me. I thought all EVSEs coming with the car have a 15A plug here in AU?!
Anyways, the 15A plug was the first thing I replaced with a 10A plug so I could use it everywhere without an Ampfibian adapter...