Planing CanView and BMS+ conversion with lithium

Due to the obvious danger of electrocution :rip: with working with 240Vdc I do not go out of my way to spoon feed others who have little knowledge and experience and end up being a danger to themselves. Sharing information has its responsibilities. I expect that people who are planning an attempt to do this project work in a closely related field. Norm does not sell the BMS2 to just anybody. He screens all his prospective customers as such a device can be dangerous in the hands of the wrong person.

I have said it before and I will say it again "240Vdc can kill you" :scared: and not to mention the possibility of your Prius :car: :target: going up in flames.:flame:

If you are not happy with your Enginer kit and you do not meet the criteria above you should seriously consider not doing this project. It is not worth the risk or any money you may save. You are better off just getting a DIY PIS kit at Plug-In Supply | Plug-In Conversions for Prius and Escape.

So please do not get angry :mad2: if you do not get the answer you expect. :nono:

 

All.

Outside temp goes over 10°C. So I done a drive testing in the "OOG" mode, say mode without heater...

You can drive in 100% EV up to 85 km/h.
If you keep the pedal accelerator at 40%:
-At 86 km/h you have 20A regen when going down a hill
-At 83 km/h you have 105A traction (More during few seconds).
Clearly this is a factory limitating in order to protect MG1 at max 8000 rpm.

More, B mode can be used and is quite interesting. Tested up to 60 km/h without any problem. When engaged you have 3 times the regen amperage you would have in D mode.

 

you did not yet go up to those speeds?
with the nimh oem packs back in 2008 that already worked and it was nice ;-)
ofcourse you can hold on a lot longer now with the A123 ;-)
i have to test the new OOG mode ;-) what firmware are you using for that

i am going to take apart the batteru pack next week and then build 5 boxes like planitair
when you dont now if you have the same cell then its better in the prototype situations that where in.
if you have a device to test cap and ohm of cell then you can match them and maybe build one large pack.

if you really read all of then you have seen that i have stated its maybe better for poeple to have a own trhead because there are a lot of posts
and i got the response that poeple liked to keep it in this topic so i did to..

but your response is not that nice.. you want a step 1,2,3 how to? and no questions asked?
then your at the wrong place

 

...

 

I have found that driving in OOG mode and having 72 cells instead of 70 the Prius cuts back on regen by reducing CCL and applying the compression brakes instead when braking. I think that the Hybrid ECU is doing this just based on the traction voltage 240V (not the SoC as the BMSplus does not fake the traction voltage). This is fine with me as this reduces the high current going into my Lifepo4 pack as these long high regen currents are probably not doing my A123 20ah cells much good. When I had 70 cells the Prius never used the compression brakes (unless I pressed hard on the foot brake) and CCL did not decrease and high currents around 90 amps were going in for long periods of time going down hill when I exited the motorway.

When driving my Prius in normal PHEV mode (not OOG) using 72 cells and the BMSplus the high traction voltage causes the ICE to run against one of the electric motors to drain power. The Hybrid ECU does this just based on voltage as 240v and over generally means the traction battery is overcharged near or over 80% SoC. This is an inbuilt safety to protect the traction battery from overcharging. When in OOG mode it cannot do this due to the ICE being disabled but it will still greatly reduce CCL to 0 amps. However DCL will not be reduced and it cannot protect the traction battery from overdischarging in OOG mode. It does all this just based on traction voltage. So when running in OOG mode you run a risk of damaging the NIMH HV battery if you let the Prius over discharge or overcharge when doing regen braking. You need to be carefull.

I remember that you were looking at building an extra battery pack. If you are planning to use OOG mode a lot like I am it would be a good idea to have 40ah to take the high regen currents. I would be interested in your experience if you go from 70 cells to 72 cells.

 

In hybrid mode just with nimh cells I already saw voltage up to 270v during regen and engine did not came in compression mode.

I don't think hybrid ecu change ccl. I believe that only the nimh ecu do this.

Today I believe that it is bms+ that reduce ccl when voltage is over 240v during a delay. When using bms+, Nimh ecu is not directly connected to other ecu and his ccl value is not transmited.

But the most important is what you explain: engine coming in compression mode with 72 cells.

Yes. But I will test with 40Ah so voltage won't go as high as with 20Ah.
I will also connect the 2 lower capacity cells that I have in // with the 2 hightest. So my battery will be better balanced.
________________________________________________

Today I have connected the charger I received, a Elcon called "2.5kW" (in fact 2kW : 8A 256v 70 cells) with my bms.
The simpliest method : a relay between them.
First test is ok.
It is really very simplier using a HV charger then the low voltage low power I used before.
Charging time is maximum 2 hours. It was 8 hours.
The charger temp have been 55°C maximum.
Output high voltage is only on if a battery is connected. So it is safe.

 

You are correct it is the NiMH ECU which changes CCL and I have also noticed that the BMSplus also changes CCL. The Canview V4 shows the original CCL which the Battery ECU is trying to send to the Hybrid ECU and also shows the modified CCL which is sent to the Hybrid ECU instead.

I believe it is the high traction voltage (not modified SoC) sent to the Hybrid ECU which causes compression mode and aggressive ICE to discharge battery - high voltage protection. What do you think?

 

Did you see your charger go into constant voltage mode and see the charging current slowly reduced to about 1 amp and then stop charging. Did you notice the LED blink change from red to white and then to green. Or did it terminate charging early due to HVC.

It is definitely worth the wait for delivery even though I had to modify the maximum voltage setting which was too high for my miniBMS. Charging each bank with a low voltage charger would mean that each bank could be charged to a slightly different level. I expect that your Peter Perkins BMS would balance your complete pack at the bottom to maximize battery range.

 

therer is a different version of the bms+ code
one that alows higher CCL ( the litium version and the normal version )
i did see CCL levels change a lot more now i have the normal version where in the litium version they stayed up more.. if i am not mistaken.


also there is new code today where the max voltage can be set to 216 volts instead of the max 210 ( bms+ ) LINK BMS+
LINK canview 4+

when you run down to 3 volts per cell this is 216 volts with 72 cells
and with a end voltage of 210 it would be 2,9 per cell
i will try this new code maybe before i take apart my battery pack so not sure if i wil be able to test this or you guys would be first to comment about it?!

i dont getr the compression mode you have with 240 volts?
when i connect mt A123 the nimh go's up to 235 max not 240
only during regen do i see for a short periode more then 240 volts that stay there only for a few min.
it drops fast and stays at 230 ( 72 x 3,2 volts ? ) to 225 ( 3,1 x 72 ) for a low time and then at 216 starts to drop faster at 3 volts per cell where several cells are alreadt at 2,9 and 2,8 what is a problem because my celllogs start to screem ;-)

the last time i did a long highway drive with lots of contanst assits and my pack temp was at 35 celsius.. what do you guys measure?
maybe i also have some high internal resistance connection inside?

 

Hi FWD,

What is your battery pack internal resistance according to your Canview when your A123 pack is connected? Mine is about 0.05 ohms to 0.09 ohms. It sounds like your battery pack internal resistance is a lot higher than mine.

I have asked Norm for a Canview V4 code that has a instant clearing of DTC when you press the PHEV/Orig button. This would be handy for OOG mode. Yet to receive an answer from Norm. He must be very busy.

I am happy with using my BPL4.hex code. As I do all my driving in OOG mode it is only the modified CCL value that is applicable and it works fine. The CCL cuts back my regen current to a lot lower level due to using 72 cells instead of 70.

 

ok well to what i now the ohm is for the oem pack? or is it based calculated on the fly based on voltage amps and voltage drops?
well anyway its the same also down to 0,05

 

The Canview would show the internal resistance of your OEM in parallel with your A123 pack when connected and it takes a while for the value to adjust from about 0.200 ohms to 0.05 ohms. You would have to ask Norm how it is calculated. I expect that it would measure the battery terminal voltage at high current compared to voltage at 0 amps and subtract to get the voltage difference and then divide by the high amps to get the internal resistance. Do this every five seconds or so and average it out.

 

No, my charger don't go in cv mode. It have a max voltage of 256v and my 70 cells goes up to 246v (3.52v*70. 3.52v is an average). I asked for a 256v because I will use 72x2 cells later.

During balancing, when bms saw a cell having a voltage over 3.54v the relay is opened and the elcon control black and red wire are disconnected.
Elcon stop immediatly the charge. A few seconds later the bms reconnect the elcon control wires and the charger increase slowly the charging amperage.
At the begining of the balancing process the charge amperage goes at the maximum value (8A). At the end of balancing, this amperage don't goes up to 8A. This because the bms cut the charge before amperage beeing at this maximum value. Something like triangular pulses with a 2A maximum for exemple.

If the bms don't cut the charge, several cells will be damaged. Those that have the lowest capacity (natural selection )
So the charge is on only if:
-all the 70 cells voltages are received
-no bad data received on the bms bus (parasite)
-all the 70 cells voltage are in a good range
-no wire between bms and charger is cut
-bms is powered

Because the charger stay always connected on 230v ac side with something like 0.18A. I will add a timer on ac side.

 

Post moved to

http://priuschat.com/forums/prius-p...914-elcon-charger-end-voltage-other-mods.html

 

update
damm these things always happen to me

i got a DTC : P0aa4 ( neg contactor stuck? closed ) and P00B0?? and P0015???

 

neg contactor stuck closed. P0aa4 is number 3 system main relay (wich is close the hall sensor)
I suppose you have this dtc when power is off ?

Have you connected the 2 lithium pole on nimh battery side of the 2 contactors ? Or one on nimh side and the other on hsd side ?

If not "cross" connected then you would have to check the neg contactor on High Voltage wires (of course with insulating gloves and so on). Is it open or closed ?

 

I removed the own fuse. drawn the voltage down with my multi meter so no I can safely touch but still going to use gloves... back in a sec with a update
o yes neg on battery side and pos on prius side.
like I told before in other topic

 

ok its stuck closed.....
dammit
well I have 2 neg spares ;-)
Wy did this happen... maybe the cross connection of sides of the main relays that I did
still don't now what those other codes are
wires and all looks good

 

If you done "cross" connection, may be the contactor is ok. Check if you have some voltage between the two side of this contactor. Zero would be bad.

I think more that it is the cross connection that fake the hsd insulating test . In this case your lithium cells where still connected after the system close the 2 main relays.

 

no i tested with my multi meter and ( diod tester ) when its all turned of the neg contactor is closed..

maybe turning of the prius with the A123 still connected is what caused this? welding?

i already took the reserve main contactors out of the salvage yard OEM housing i have
its not that hard! the relays are mounted on a plate then can be removed from the housing.
i will do this tomorrow!

only thing thats different from before is that i used relay 2 of the canview to disengage the EV try.

when i have a voltage above ( i break with a almost emptry A123 pack and voltage go's up )Ev try voltage and speed is low then it wil engage EV mode what i dont want because in just a few sec the voltage drops again but the prius stays in EV mode where my cellogs start to beep.

so i paraleled the relay 2 of the canview to switch when ev mode is ON and voltage is below 220 volts.
this way ev is disables again at those low voltages

edit
add some pics