Planing CanView and BMS+ conversion with lithium

[Mr-plugin]

I ordered 70 40 ah cells today, The BMS I made with Celllogs is working. I am probably going to use a PFC2500 charger. I will need to make additional circuit boards and order some more Cellogs to complete the BMS. I have contactors out of a extra prius pack I plan on using. I instlled the Canviw and BMS+ last week end. John do you have problem with the Canview/Bms kicking you out of EV when you are coming to a stop?

[lopezjm2001]

Originally Posted by Mr-plugin

I ordered 70 40 ah cells today, The BMS I made with Celllogs is working. I am probably going to use a PFC2500 charger. I will need to make additional circuit boards and order some more Cellogs to complete the BMS. I have contactors out of a extra prius pack I plan on using. I instlled the Canviw and BMS+ last week end. John do you have problem with the Canview/Bms kicking you out of EV when you are coming to a stop?

Hi Plugin,

Which brand of cells did you get, Calb 40ah?

I bought an Elcon charger at EVAssemble

http://www.evassemble.com/index.php?...products_id=17

It is limited to a 5 amps output. It may also be used to charge the Prius NiMH directly as it is limited to max 5 amps output.


What are you going to use for balancing the cells? CellLog8s are really accurate and work well for me. But they only provide voltage protection and data logging but no balancing. I thought of getting a Orion BMS but it just too pricey. I could use my EV Display unit to monitor the SoC of a 230Vdc lithium pack and my miniBMS with 4 slave boards.

My EV function works perfectly, it does not kick me out of EV at coming to a stop. It may be caused by how you have setup the EV mode settings on your Canview. Unless you are referring to Stealth mode. The Canview PHEV screen shows the seven conditions you must meet in order to go into EV mode. If you watch them it may tell you which condition caused you to fall out of EV. You really need to read all the info on Norm's website to understand what it does.

[Mr-plugin]

Originally Posted by lopezjm2001

Hi Plugin,

Which brand of cells did you get, Calb 40ah?

I bought an Elcon charger at EVAssemble

Elcon 1500W HF/PFC LiFePO4 Battery Charger [Elcon 1500W HF/PFC] - $340.00 : EV Assemble, All for Electric Vehicle!

It is limited to a 5 amps output. It may also be used to charge the Prius NiMH directly as it is limited to max 5 amps output.


What are you going to use for balancing the cells? CellLog8s are really accurate and work well for me. But they only provide voltage protection and data logging but no balancing. I thought of getting a Orion BMS but it just too pricey. I could use my EV Display unit to monitor the SoC of a 230Vdc lithium pack and my miniBMS with 4 slave boards.

My EV function works perfectly, it does not kick me out of EV at coming to a stop. It may be caused by how you have setup the EV mode settings on your Canview. Unless you are referring to Stealth mode. The Canview PHEV screen shows the seven conditions you must meet in order to go into EV mode. If you watch them it may tell you which condition caused you to fall out of EV. You really need to read all the info on Norm's website to understand what it does.

Hi John.
I bought the Calb cells. I do not plan on using a balancing system unless I have to. There are many people that say they stay balanced if you treat them right. If I keep my DOD from getting too low I should be ok. The high and low cut off is most important.

I plan on buying the PFC2500. I will get it here in the states. Another $125, but if I have trouble I do not have to send it back to China.

I have not hooked up the Relays for the EV with the canview, I have just been using my old EV button. Of course I believe it is doing the same same thing (grounding the EV pin in the PCM) so I do not know why it is doing it. I have a hill I go down from my house to go to work and every morning now it will kick out of EV as I am coming to a stop at the bottom of the hill. I think it has to do with the SOC change when slowing down with a moderate braking force from the BMS+. I will disconnect it later and go for a drive.

[lopezjm2001]

Hi Plugin,

Have you made allowance for the CellLog8s not evenly drawing current from all cells. Solution is you only use CellLog8s connections for first six cells or modify each CellLog8s PCB by making a jumper connection.

Not using a balancer may be wise. Just do a manual balance now and then by connecting all cells in parallel for 24 hours. It would be a good idea to use a EV display unit which will give you an accurate SoC reading which also has outputs which you can use to shutdown when SoC reaches a low level.

Sounds like the BMSplus is throwing you out of EV mode during regen as it sends out a fake high SoC level. When the EV function is controlled by the BMSplus it knows when you have selected Auto EV and it can control it and lowers the fake SoC to a more real value when in EV mode to protect the NiMH battery. I am betting that if you connected a Canview relay to do the EV function this would not be a problem. Ask Norm. You also have to remember that at the moment you are not using extra battery packs in parallel which could be a factor involved.

From memory I think that when the BMSplus has the PHEV button switched off it uses Norm's algorithms to calculate actual SoC so maybe this could happen.

[Mr-plugin]

Originally Posted by lopezjm2001

Hi Plugin,

Have you made allowance for the CellLog8s not evenly drawing current from all cells. Solution is you only use CellLog8s connections for first six cells or modify each CellLog8s PCB by making a jumper connection.

Not using a balancer may be wise. Just do a manual balance now and then by connecting all cells in parallel for 24 hours. It would be a good idea to use a EV display unit which will give you an accurate SoC reading which also has outputs which you can use to shutdown when SoC reaches a low level.

Sounds like the BMSplus is throwing you out of EV mode during regen as it sends out a fake high SoC level. When the EV function is controlled by the BMSplus it knows when you have selected Auto EV and it can control it and lowers the fake SoC to a more real value when in EV mode to protect the NiMH battery. I am betting that if you connected a Canview relay to do the EV function this would not be a problem. Ask Norm. You also have to remember that at the moment you are not using extra battery packs in parallel which could be a factor involved.

From memory I think that when the BMSplus has the PHEV button switched off it uses Norm's algorithms to calculate actual SoC so maybe this could happen.

I read about the jumper. I have not done it to the celllogs i have but is in the plan. Do you just have your 4th relay wired one pin to the ev pin to the pcm and the other to ground or did you add a extra relay in between?

[lopezjm2001]

Originally Posted by Mr-plugin

I read about the jumper. I have not done it to the celllogs i have but is in the plan. Do you just have your 4th relay wired one pin to the ev pin to the pcm and the other to ground or did you add a extra relay in between?

My Australian Prius comes with factory fitted EV switch. Relay one is reserved for EV mode. I just placed the two relay terminals across my EV switch. The current used by EV switch Is small so only the Canview relay was used.

Relay 4 is dedicated to PHEV, which I would use to energise a 200 amp contactor to engage the lithium pack. Not sure wether you need to use an extra relay, I cannot remember what the Canview relay contacts are rated for. Some users use the Canview relay to charge dump the NiMH pack which is what we are doing. Best to ask Norm if using this relay 4 to engage lithium pack is OK. Normally extra NiMH packs are connected directly in parallel permanently and no contactors are used to engage each one. I would not connect a lithium pack directly in parallel with a NiMH as the NiMH pack has a high self discharge rate which increases as SoC nears 80%. The lithium has a very small self discharge rate. The NiMH would bleed the lithium. A 230Vdc NiMH pack correlate with a NiMH SoC of 60% which is the lower target SoC used by the Prius under normal circumstances. The target drifts between 60 and 70 % SoC. I read in a forum that the Prius microcharges the Prius battery pack during normal operation to keep it between 60 and 70 % SoC. So having a lithium pack of 230Vdc is well chosen to avoid overcharging the HiMH. Even if the lithium enagage contactor should become welded close the NiMH is still protected from overcharge. It probably also avoids DTCs.

You really need to read Norm's website thoroughly.

I use relay 5 for my HV battery fan speed modification.

I use relay 2 and 6 to automatically switch my two Enginer kits.

Everything I am saying comes from Norm's website so do not take my word that I am correct. Double check everything with Norm's website and ask Norm as it was mostly designed to go with extra NiMH packs.

On one occasion I let my NiMH become overcharged to 86% and the Canview automatically switched off all relays which shutdown my converter. A good reason to use a Canview relay instead of a switch. It is inbuilt safety feature of the Canview.

One question remains - which side of the Prius current sensor to connect/engage the NiMH pack. I am leaning towards the the other side (not the battery side) so the original battery ECU will know how much current is going into the NiMH battery. This way the original battery ECU has a more accurate SoC if it can measure all the current that goes in and out.

[lopezjm2001]

My Australian Prius comes with factory fitted EV switch. Relay one is reserved for EV mode. I just placed the two relay terminals across my EV switch. The current used by EV switch Is small so only the Canview relay was used.

Relay 4 is dedicated to PHEV, which I would use to energise a 200 amp contactor to engage the lithium pack. Not sure wether you need to use an extra relay, I cannot remember what the Canview relay contacts are rated for. Some users use the Canview relay to charge dump the NiMH pack which is what we are doing. Best to ask Norm if using this relay 4 to engage lithium pack is OK. Normally extra NiMH packs are connected directly in parallel permanently and no contactors are used to engage each one. I would not connect a lithium pack permanently directly in parallel with a NiMH as the NiMH pack has a high self discharge rate which increases as SoC nears 80%. The lithium has a very small self discharge rate. The NiMH would bleed the lithium. A 230Vdc NiMH pack correlate with a NiMH SoC of 60% which is the lower target SoC used by the Prius under normal circumstances. The target drifts between 60 and 70 % SoC. I read in a forum that the Prius microcharges the Prius battery pack during normal operation to keep it between 60 and 70 % SoC. So having a lithium pack of 230Vdc is well chosen to avoid overcharging the HiMH. Even if the lithium enagage contactor should become welded close the NiMH is still protected from overcharge. It probably also avoids DTCs.

You really need to read Norm's website thoroughly.

I use relay 5 for my HV battery fan speed modification.

I use relay 2 and 6 to automatically switch my two Enginer kits.

Everything I am saying comes from Norm's website so do not take my word that I am correct. Double check everything with Norm's website and ask Norm as it was mostly designed to go with extra NiMH packs.

One question remains - which side of the Prius current sensor to connect/engage the NiMH pack. I am leaning towards the the other side (not the battery side) so the original battery ECU will know how much current is going into the NiMH battery. This way the original battery ECU has a more accurate SoC if it can measure all the current that goes in and out.

[planetaire]

Originally Posted by lopezjm2001

...From memory I think that when the BMSplus has the PHEV button switched off it uses Norm's algorithms to calculate actual SoC so maybe this could happen.

Yes, but not specially when EV-switch is off. Bms+ always calculate SoC.

Here is an example of Soc send by Bms+ to Hybrid Ecu during 20km. Lithium 40% discharged at the beginning and 80% at the end.

Soc is 64% or less when I press the Ev-switch. When not pressed it is 74% falling when battery are depleted. Because I don't use Canview, I am sure that bms+ knows ev-mode is on because this is a pid send on bus can.

I would not connect a lithium pack permanently directly in parallel with a NiMH as the NiMH pack has a high self discharge rate which increases as SoC nears 80%. The lithium has a very small self discharge rate. The NiMH would bleed the lithium.

Yes but it is first important during charging, voltage goes up to 245v. Nimh would'nt like during a so long time.

So having a lithium pack of 230Vdc is well chosen to avoid overcharging the HiMH. Even if the lithium enagage contactor should become welded close the NiMH is still protected from overcharge. It probably also avoids DTCs.

That's why 70 A123 cells is a good number. Nimh is over 240v just during few seconds when // packs. Voltage without any electric consumption is near 235v when lithium is fully charged and falls to 218-225v when depleted.

I connect Lithium via contactors directly to Nimh. Hall current don't see current between Nimh and Lithium.

[lopezjm2001]

Hi Planetaire,

Thanks for your input.

1.Where exactly did you connect the lithium battery pack positive and negative to the NiMH HV pack?

2. What size cable did you use?

3. Did you use metal screened cable? Which type of cable insulation?

4. What rating contactors did you use. I assume you used a contactor on each polarity.

5. Did you use 150amp Anderson plugs to connect and disconnect each of your 5 lihium battery banks.

6. Are you using a service fuse for your Lithium battery pack which you can remove to make it safer to work on and to remove your lithium packs.

7. What size fuse/s did you use. Did you use HRC fuses/s.

[planetaire]

Originally Posted by lopezjm2001

Hi Planetaire,

Thanks for your input.

1.Where exactly did you connect the lithium battery pack positive and negative to the NiMH HV pack?

Exactly like for // Nimh with nimh.

One pole on one nimh contactor, battery side.
For the second pole you have to add a small wire (15-20cm) that goes in the hall current sensor in place of the original wire. Connect nimh and lithium at one end of this wire, the other end beeing on the second nimh contactor, battery side.

2. What size cable did you use?

16mm² (5 awg)

3. Did you use metal screened cable? Which type of cable insulation?

No, but it would be better. Wire is called here HO7. Wire is in a orange "tubing".

4. What rating contactors did you use. I assume you used a contactor on each polarity.

100A continuous 2 contactors is better but not necessary.

5. Did you use 150amp Anderson plugs to connect and disconnect each of your 5 lihium battery banks.

I use 50A without overheating. 75A would be safer.

6. Are you using a service fuse for your Lithium battery pack which you can remove to make it safer to work on and to remove your lithium packs.

No I disconnect 5 sub-packs before working.

7. What size fuse/s did you use. Did you use HRC fuses/s.

Yes a 100A fuse HRC.