[Driving] Freelander EV With Gen1 Leaf electrics and EVBMW VCU

[Alibro]

New vid

[arber333]

Hm... why not use a relay instead of that switch? Of course you would start relay with PP connected to GND.

[Alibro]

Hm... why not use a relay instead of that switch? Of course you would start relay with PP connected to GND.

Good question!
I should have mentioned in the video that the switch was already there for a different purpose but was no longer needed, so when I realised the issue with the pump it was an easy way to stop it. I need to do more work on automating charge start and stop along with tidying up the LV junction box so that is on the long (and strangely growing) list of things to do.

[Alibro]

Last couple of weeks I've been working on getting a heater for the cabin. I've been on the Mitsubishi Phev heater thread and finally got some heat.
Here is a link to the thread.

viewtopic.php?p=66607#p66607

Now I need to gather up the inclination to install it.

[Alibro]

I haven't done much to the car last couple of weeks except drive it as I got some work replacing Routers in Post Offices so kinda tired at night.

I did manage to edit a video that was made a couple of weeks ago so here you go.

[Alibro]

So today I managed to pretty much complete the LV junction box and get the car working again (spinning the motor while in neutral and charging). I made a couple of minor errors with the location of some wires but they were easily sorted and no harm done. Before connecting the battery properly I hooked it up through a 12V bulb to confirm there were no shorts.

In the photo below you can see how I've tried to tidy things up a bit with the fuse holders. As it turned out I'd have been better off with 3 smaller 6 or 8 way fuse boxes than two 12 way as I had to resort to Wagos for wires going to ignition position 1 but it is still much neater than before.

I have been documenting every wire as they were connected so hopefully when I go back to add stuff or make changes it will be a lot easier.

Then to see what would happen I connected the heater up and Woo Hoo, we have heat! Nice warm air coming through the vents with the heater on. Now I need to route the controller through the bulkhead and mount it in the cabin.

[Alibro]

And of course it wouldn't be an update from me if I didn't run into a problem.
The brake boost started playing up so I'm having to reconfigure the vac plumbing. I had originally plumbed it with a vac sensor that was controlled by an Arduino but the setup was always a bit leaky and the pump would kick in every ten minutes or so. Today it was kicking in every 30 seconds or minute and was getting more and more erratic so I'm replacing the sensor with a Volvo vac switch that is either on or off. I had ordered it months ago but it was slow to arrive so I went with the original setup. I'll wire it through a relay to drive the vac pump and hopefully simplify everything. Others here have used a similar vac switch and recommend it so hear's hoping.

[Alibro]

I got it installed after my last post and so far so good with the vac boost.
Of course a couple of other issues have cropped up but hopefully should be simple to sort. I know what one of them is as I had the same problem before, when I turn on the lights I hear a relay dropping so that is a simple voltage glitch that needs some rewiring. The other is the heater isn't working so I need to do some digging to figure it out. Hopefully it is simply a bad connection somewhere as I had it working before.

[Alibro]

So the great news is we are back on the road again after more than two weeks major organ surgery (cabin heater) and some plastic surgery to the LV junction box.
The vac boost is working a treat and so far everything else is too.
The cabin heater issue was entirely self inflicted as I had the Arduino unprotected as I was soldering wires for the LV JB and I think I may have dropped a piece of solder on it but whatever the cause the Arduino was toast.
Now I need to get the controller and display for the heater installed and tidy up a few things.

[Alibro]

This is a copy and paste from the Outlander heater thread.

Here is a quick update of the heater situation now I have it installed.

It works!

The longer version includes a minor disaster and a change in design.
While testing I managed to drop some solder on the board while it was running. This caused the operation to be somewhat sub-optimal so after first replacing the MCP2515 I then had to replace the Arduino and of course it was no longer soldered to the vero board.
Originally I had planned to mount the board under the bonnet and feed wires through to the dash but while staring at the new pile of wires I had an idea.

OK so neat it isn't but this was more a proof of concept than a final installation. In order to tweak the code I will need to remove the Arduino as I didn't give myself enough room to plug in a cable but that can wait a bit. I have plenty of other things to work at in the meantime.

Jamie/TurboPete's code works great however in my application I might need to adjust the temperature difference before the heater switches to half power. It looks like it switches to half power while around 10°C below requested temp. This means if I request 55°C it only gets to around 50°C which is not quite enough. I find myself turning it up to 61 or 62°C to get the desired 55°C.
I assume this will change as we get into late Spring so for now I am keeping the adjustment and code as is. I have a second ash tray that I can use if I decide to use Arber333's code without a POT.

[Alibro]

Latest video



And I put a few miles on the car over the weekend.

I always wanted this to be a practical workhorse that I don't need to be too precious about

Every time I use it to tow a trailer it's another time I don't burn out a little bit more of SMBO's Kuga clutch.

[Jacobsmess]

good news that things are all running smoothly! Acouple of Qs, people always talk about EVs cant tow, which you're obviously proving wrong, how does it effect the range?
Also, do you have the Leaf BMS working in your conversion yet? I'm looking to implement it in mine but would be interested to see other examples, there both an abundance of information out there but few examples of a concrete, "this is how you do it" somewhat unsurprisingly. If I can I'd like to add a proper "how to" to the wiki, but at first I need to know how!

[Alibro]

Thanks, I've now done almost 500 miles since it pigged on me (technical term) and it's been driving great.
For people to say EV's can't tow is just stupid, to say they can't tow very far is a bit less stupid, especially if the load is bulky and/or heavy, also if you need to recharge with a trailer attached it is not easy. In my case I have only towed for a few miles so it is difficult to say how much difference it makes.
Keeping this car 4WD and keeping the towbar were two priorities for me as I wanted it to be as practical as possible. I plan to go to a town 4 or 5 miles from home next week to collect stone to fill holes in our lane. It's a job that needs done every year and I usually get 1 tonne at a time.
The BMS will be happening this summer but I have concerns over the layout of my batteries. The LEAF BMS is designed for a split in the pack at cell 48/49 but my pack splits at a different point so I need to come up with a plan to prevent the BMS going up in smoke.

[Alibro]

The last few days I've been struggling to get my head around the BMS again. Although it probably won't be able be able to keep the pack balanced it's a good idea to have it working as I can use a simple Bluetooth dongle and App called LeafSpy to monitor the voltages of each cell. Having the BMS working means I'll be able to see if any cells are out of balance and if necessary I can intervene manually. I really should have had it sorted months ago but I knew it was going to be a pain so kept putting it off. I had it connected and working a couple of years ago on the bench but that was with all the modules in one place. Now I have some in the front, some in the fuel tank area and some in the boot so it's not so simple.
During the week I spent several evenings working on it and then pretty much the entire day yesterday soldering testing, pulling apart and resoldering cause I messed up.
This was the mess I was in earlier.

After many cockups, a few poor decisions and some generally dodgy workmanship I think I have it sorted.
Some time ago I made up a spreadsheet to give me the expected voltage at every connection for any given cell voltage. I was able to test all the voltages and even discovered a fault in the spreadsheet so today I'll sort out a 12V supply for the BMS, hook up the CAN leads and hopefully see the condition of the battery pack.

My confusion was caused by the numbering convention by Nissan, they count the most positive cell as cell 1 and most negative as cell 96. The lowest number cell in the boot is 41 so I started there when I should have started at 96. I figured trying to meter and count the voltage from cell 96 to 41 would be too complicated so I metered from the most positive end and managed to confuse myself completely. Eventually I dug out the spreadsheet and once I had this in front of me it all started to make sense.

I got the connection numbers from the Nissan Leaf service manual and it worked before so I'm confident it is correct but another complication is at cell 48. There is an extra negative connection for cell 48 because the BMS is galvanically isolated between cells 48 and 49, to protect it from stray current drain when the HV service disconnect is pulled. Basically if this was not there the BMS would be shorting out the HV service disconnect, thereby maintaining the HV circuit, This would not only be dangerous but if there were a stray power drain it would melt the BMS.
My service disconnect and contactors break the pack at cell 41/42 so I have to try and figure out a way to ensure the BMS is never connected when the contactors are open. I'll probably use a relay to make/break the connection to cell 49 and ensure it is only ever active while the car is in drive mode.

Has anyone ever tried this before? I had heard I am likely to cook the BMS with the battery layout I'm using but I don't have much choice as moving battery modules to the front of the car is not an option without a LOT of work.

[johu]

You could move the "negative" contactor between 48 and 49 and move positive and precharge to the end of the pack. Don't break between 41 and 42, by Murphys law this can and will go wrong

[Alibro]

You could move the "negative" contactor between 48 and 49 and move positive and precharge to the end of the pack. Don't break between 41 and 42, by Murphys law this can and will go wrong

That's a great idea thanks. I already have two contactors in the rear battery box breaking the neg and pos as well as in the HV junction box so it should just a matter of reconnecting the neg.
I was concerned there would be positive voltage on the cable and connector If I broke the pos and neg at 48 but it never occurred to put only the neg contactor in there.
Thanks again.