[JulesElectronics]

Hi, I have a 2016 Kangoo maxi van with a 22kWh battery and a 3.6kW built-in charger, the problem is that means realistically a 80 mile maximum range and a 7 hour recharge time. Now this is perfectly good almost all of the time but I would like to occasionally go longer distance or go somewhere and charge faster than I can right now.

Now I could just sell this van and buy the better 33kWh version, or the eNV-200 which would give a longer range / faster charging, but I would like to know more about the inner workings of EVs and also the newer versions are pretty pricey.

My plan is to integrate a 2nd battery pack from a written-off 2019 Kangoo.

 

[JulesElectronics]

The 33kWh battery out of the 2019 Kangoo

And with the lid off:

The pack consists of 12 blocks of 8 LG chem cells, I believe they are prismatic (rectangle shaped, wrapped in foil). The battery management system (BMS) / Lithium Battery Controller (LBC) is the silver box on the left with loads of wires going into it (from every single cell), the black vented block to the right houses the precharge and main contactors, a 275A fuse and what looks like some current sensing circuitry.
There is another fuse, mid-pack under the orange cover on the left middle. I removed it, carefully, to make working on the pack slightly safer.

With the cover of the contactors / fuse/ current sense removed:

Fuse on the right, grey main contactor, black precharge contactor in the centre and silver high power resistor for precharge bottom left.

Measured voltage on battery pack:

 

[Tandy0]

I had an idea about doubling a van's battery for long journeys some time ago. Rather than permanently installing the extra battery, it involves building a rack for it in the back of your garage that you can reverse your van into. You then unbolt from the rack, and bolt to the van. I would put some sort of extention in for the battery cables, so you can switch over which battery you are using with plugs.

 

[JulesElectronics]

Yes, Tandy0, that's what I'm thinking - for now I'll just put the 2nd battery in the back and join the HV up across the 1st (with other considerations...). I have a forklift at work so just lift the 250kg pack in and out fairly easily.

 

[Tandy0]

There was a guy on Youtube who did this with a leaf. He kept the two batteries completely separate. Just plugged one in. drained that, then unplugged it and plugged in the other one. This did not require any modification to the BMS/charging system.

 

[JulesElectronics]

I have seen that too, and I think that would work if I had another 22kWh battery, but I have a 33kWh and my understanding from a discussion with several Renault technicians is that the cell structure is different / the BMS is VIN locked / the van is expecting to see a 22kWh battery and will not understand a 33kWh without some modification. I have several ideas to try of increasing complexity, the simplest would be to swap all connections from the first to the second battery. I am thinking to bring the high voltage and control wires up into the back of the van so if it doesn't work as expected, I can easily bypass changes and connect the first battery back in and continue to drive it / research further without disabling it yet.

A second issue I have is that the control connectors between the two batteries are different, the 22kWh pack has a single 12 pin connector with 10 pins connected but the newer 33kWh pack has a pair of 12 pin connectors 4 pins and 6 pins used. I will have to figure out which pin does what on battery one without removing it from the van and hopefully the signals aren't too different...

 

[dk6780]

There was a guy on Youtube who did this with a leaf.

Really? Any chance of a link as my understanding is that if you connect a pack other than the one that it is coded for the BMS of it just goes into limp mode. That is why Muxsam (Emile) built his MITM can attack hardware and software, and spent a long time reverse engineering a way around this and other issues. As I understand it you can connect the HV side of the systems in parallel without that being too much of an issue (and various people have done this including Muxsan with a different pack chemistry) but that is something that you need the two battery voltages to be near enough matched to achieve which is OK as a one off but not something that you can just drop in and out.

 

[Tandy0]

Really? Any chance of a link as my understanding is that if you connect a pack other than the one that it is coded for the BMS of it just goes into limp mode. That is why Muxsam (Emile) built his MITM can attack hardware and software, and spent a long time reverse engineering a way around this and other issues. As I understand it you can connect the HV side of the systems in parallel without that being too much of an issue (and various people have done this including Muxsan with a different pack chemistry) but that is something that you need the two battery voltages to be near enough matched to achieve which is OK as a one off but not something that you can just drop in and out.

IIRC the BMS of both batteries was kept. It's a long time since I saw the video, and cannot find it now.

 

[JulesElectronics]

"A second issue I have is that the control connectors between the two batteries are different, the 22kWh pack has a single 12 pin connector with 10 pins connected but the newer 33kWh pack has a pair of 12 pin connectors 4 pins and 6 pins used. I will have to figure out which pin does what on battery one without removing it from the van and hopefully the signals aren't too different... "

control connectors on the 22kWh battery:

Control connectors on the 33kWh battery:

It looks like there are the same number of pins on both battery packs,

 

[dk6780]

Do you have access to the two wiring diagrams to know if the 33kWh battery is a forked lead from the same modules or whether Renault have separated functions previously controlled from a single module?

 

[JulesElectronics]

I don't have any diagrams unfortunately, hoping the control for both batteries is similar enough. I don't really want to remove the 22kWh battery from the van to figure out the pinout so have made up a test lead to measure resistances / voltages. I think I've figured out most of how the 33kWh battery works from tracing the wires inside and measuring things:

Test cable for 22kWh battery:

The control connections seem almost the same:

CANL
CANH
Permanent 12V (power for the BMS / LBC?)
Ground
Ground
Ground
Precharge contactor +ve
Precharge contactor -ve
Main contactor +ve
Main contactor -ve

Except the 33kWh battery has precharge -ve and main -ve joined together.

Both pairs of relay control wires don't appear to be joined to anything until the ignition key is turned to the first position, at which point both -ve wires connect to ground, then precharge +ve connects to +12V, then approx. half a second later main +ve connects to +12V.

I rigged up a junction box on the HV connector in the front to test the voltage on the HV bus.

 

[Toomba]

the BMS is VIN locked / the van is expecting to see a 22kWh battery and will not understand a 33kWh without some modification. I have several ideas to try of increasing complexity, the simplest would be to swap all connections from the first to the second battery.

According to my sources of info and experience (I swapped batteries on Zoes), you can swap batteries between Renault electric cars. The BMS is not hard coded into the car. The connectors might look different, but the signals are the same. The only difference is on Zoes that use 1 x power contactor instead of 2, like in Kangoos or Fluence ZE.

Your Kangoo ZE is similar to my Fluence ZE. Check my topic in tinkering with it in this forum.


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[Toomba]

BP1X-RG: fused +12V permanent to BMS - red wire.
3FB4-VI: fused +12V to power relays from fuse box under the bonne - violet wire
2AD-OR: GND control signal to Power Relay 1 - orange wire.
2AE-VE: GND control signal to Power Relay 2 - green wire.
2AC-MA: GND control signal to Precharge Relay - brown wire.
55AQ-VI: CAN L - violet wire.
55AP-BA: CAN H - white wire.
MB-NO : electrical earth - black wire

This is for the black connector on the 22kWh battery pack.

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[JulesElectronics]

While the junction box was in the front, I thought I'd try applying high voltage DC from a PSU to see if it's happy to charge without going through the built-in charger. I set the PSU voltage to the battery voltage, set a 1A current limit and carefully connected the PSU to the HV bus. Then I increased the voltage, the voltage came up by 0.1V before the current limit kicked in. Then I increased the current limit to 5A and it seemed to be alright. With the ignition on, the current power displayed on the dashboard said -2kW which makes sense - 380V @ 5A is approx. 2kW.

Of course I could easily over charge / damage the battery by just increasing the voltage more and more.

Next I drove around until the van said less than 4 mile of range left, measured the HV bus voltage, then recharged it to 100% using the built-in charger and checked the HV bus voltage again.

Battery empty voltage = 333V
Battery full voltage = 396V

 

[philsuarez]

Love the technical talk however I think I’d just buy a van with a bigger battery lol! Looking at the new Zoe van which would be an ideal second van for my floristry business

 

[JulesElectronics]

Now I've rebuilt the junction box that was in the front of the van to fit it underneath between the battery and the van loom, conveniently fit where I assume the exhaust would be on the diesel version. I used the connector from the 33kWh battery, the HV cable salvaged from the other van and 35mm2 HV cables so that the loom on the van isn't compromised and if I want to return it to how it was, I can.

Fits neatly under the cover:

Just for a while, I have everything hanging out so I can play... The high voltage relay (kilovac ev200) is behind and is used to connect the HV from battery 1 to battery 2, the HV negatives are permanently joined together.

 

[JulesElectronics]

BP1X-RG: fused +12V permanent to BMS - red wire.
3FB4-VI: fused +12V to power relays from fuse box under the bonne - violet wire
2AD-OR: GND control signal to Power Relay 1 - orange wire.
2AE-VE: GND control signal to Power Relay 2 - green wire.
2AC-MA: GND control signal to Precharge Relay - brown wire.
55AQ-VI: CAN L - violet wire.
55AP-BA: CAN H - white wire.
MB-NO : electrical earth - black wire

This is for the black connector on the 22kWh battery pack.

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I've tried connecting the 2nd battery control lines for precharge and main relays across first but it disabled the van and gave the error "battery charging impossible". I was lucky to be able to clear the error and make it drive again! I think I still haven't figured out the pinout correctly. Does it make sense that:

Turn ignition to 1, pin 7 violet (+12V for relays) goes to 12V and pin 10 brown (GND control for precharge) goes to ground, activates precharge.
half a second later (assuming it's precharged the HV bus correctly) pin 8 orange (GND control for relay1?) goes to 12V and pin 9 green (GND control for relay2) goes to ground, activates main contactor.

If there's 3 gnd control wires, and 3 relays then? I thought there is only the precharge and main contactor?

 

[Toomba]

In the 22kWh battery you have 3 relays.
In the 33kWh I'm not sure. You might have 2 like in the Zoe. From the pictures you posted I can't figure out.

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[Toomba]

I've tried connecting the 2nd battery control lines for precharge and main relays across first

Be more specific. Did you disconnect the 22kWh control lines? Or are they connected in parallel?

You can't connect them in parallel with 2 relay boxes, 2 x bms etc The EVC is very smart it will detect any anomalies.

They have to be connected on the HV side permanently in parallel before the relay box and current sensor.

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[JulesElectronics]

In the 22kWh battery you have 3 relays.
In the 33kWh I'm not sure. You might have 2 like in the Zoe. From the pictures you posted I can't figure out.

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Thanks Toomba, I didn't know that - was assuming the battery packs are very similar. Do you have any info on what the three relays are doing? Like the two power relays switch the +ve HV in and -ve HV separately? Is there a wiring diagram for the relay block in the 22kWh battery?

Be more specific. Did you disconnect the 22kWh control lines? Or are they connected in parallel?

You can't connect them in parallel with 2 relay boxes, 2 x bms etc The EVC is very smart it will detect any anomalies.

They have to be connected on the HV side permanently in parallel before the relay box and current sensor.

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I didn't disconnect the 22kWh control lines, but didn't connect the permanent 12V or CANBUS because the BMS's would conflict with eachother. I thought I'd figured out enough to connect the precharge relay and main contactor relay to the control lines already going to the 22kWh battery so that the van can command both sets of relays at the same time. Perhaps a mistake - as you say the EVC knew something was wrong...

I suppose to get round the EVC detecting extrra current to drive the relays I'll need some detection circuit and power the extra relays in a different way.