Is it possible to make a CCS to CHAdeMO adapter?

[johnr]

I have gotten many requests for a CCS adapter from owners of vehicles with CHAdeMO ports. Since we're moving toward CCS adoption and there are getting to be more CCS chargers than CHAdeMO, this is a highly requested need. I always tell them such an adapter is not feasible to make because the two standards are so different. My understanding is that a microcontroller with some custom firmware would be needed to translate the signals in real-time and ensure the operational parameters are kept in check - but that's what you all do, right? Looking forward to discussing. If it's feasible, let's do it!

[johu]

It would be quite costly as the stupid sockets and plugs are so expensive but apart from that I don't see a technical issue. Just use the existing Tesla CCS port and the ongoing development around it. Then just do a little protocol translation between CCS and ChaDeMo. I think all you need is a 2 CAN port micro, e.g. STM32F105.
The only thing I'm not sure about is power. ChaDeMo supplies 12V and up to 2A to the vehicle, CCS does not, right? So may need a little battery to bootstrap and then use a small SMPS to convert the 400V charge voltage to 12V

[celeron55]

In CCS the charger precharges its output to a voltage specified by the EV before the EV closes its contactors, while CHAdeMO specifies a big diode at the charger output to avoid needing any kind of charger output precharge. Makes things tricky without support from the car side.

There might also be other details that could end up being interesting at the least.

EDIT: Of course there's the rather obvious difference of CHAdeMO using CAN and CCS using Green PHY.

[johnr]

I'm not concerned about the component costs, if it's feasible to do. The plugs are affordable enough to make it worthwhile. Unfortunately this is too technical for me and I just don't have the time to go at it alone, but if it's possible to do, I'm more than happy to support and work with whoever is willing to take on the project. Again, it all depends of course on whether it is realistically feasible.

[johu]

So you'd be willing to sponsor the hardware to someone who wants to build this?

[johu]

In CCS the charger precharges its output to a voltage specified by the EV before the EV closes its contactors, while CHAdeMO specifies a big diode at the charger output to avoid needing any kind of charger output precharge. Makes things tricky without support from the car side.

I've seen this on a combined CCS/ChaDeMo station. Basically the charger closes the vehicle switch, then precharges its output, then closes its own switch.
You're right in ChaDeMo the car doesn't communicate its momentary battery voltage, only charge target voltage. One way to get around it is closing the cars relays, measuring the voltage and then close an extra relay contained within the adapter as soon as CCS commands to do so.

EDIT: Of course there's the rather obvious difference of CHAdeMO using CAN and CCS using Green PHY.

Yes but that the CCS protocol details are abstracted by the Tesla charge port controller which to my knowledge communicates with the vehicle via CAN. So an adapter just talks ChaDeMo on one port and "Tesla CCS CAN" on the other.

By now the adapter sports

• Tesla CCS port
• A small bootstrap battery
• a small 400 -> 12V SMPS
• a roughly 200A relay
• A control PCB

Feasible?

[jgpev]

The Chademo MiEV power BOX from Mitsubishi comes with a 12v lighter socket adapter and I would think something like this would check the box. I think the alternative would be to use a USB battery bank with 5v->12v upconverter, because that will make it more convenient than having to remember to charge your adapter.

Do we think this CCS to Chademo adapter would be smaller than the three phase AC to chademo adapters already on the market due to lack of need to rectify the current?

[johu]

Yes lighter socket would work as well The idea with the battery: it only needs to provide enough energy to close the car relay and is then immediately recharged by a small DC/DC converter.

There are no power electronics in this so it would be much smaller than a ChaDeMo charger.

[johnr]

So you'd be willing to sponsor the hardware to someone who wants to build this?

Yes, absolutely.

[johu]

After just 2.5 years this gets revisited
Using this project here viewtopic.php?t=2262 I want to build such an adapter for my Touran.
Planning on a straight through connection from CCS to CHAdeMO power pins, no diode or relay.
This means it will only work with DIY conversions because it will require an extra CAN message containing the actual battery voltage.

I don't know enough about CCS to make up a meaningful sequence (please ya knowitalls chime in ) but here's the rough idea:
- Power CHAdeMO port with 12V via an extra cable from cigarette lighter
- Receive battery voltage via special CAN message
- Set up CCS session
- Send received voltage to CCS charger for precharge
- When instructed by CCS close charge port relays
- Forward CHAdeMO current request to CCS

[uhi22]

Good starting point. For the CCS we need the following data, and for each of them we can either take it from the Chademo data, if available, or just "invent" some fix value.
(1) For ChargeParameterDiscovery:
- SOC
- EVMaximumCurrentLimit
- EVMaximumPowerLimit
- EVMaximumVoltageLimit
- EVEnergyCapacity (The complete capacity of the battery. Not clear why the charger wants to know this.)
- EVEnergyRequest (How much kWh we want to charge. Most likely does not really matter.)
- FullSOC (At which SOC the battery is considered at full, e.g. 100%)
- BulkSOC (At which SOC the power will drop significantly, e.g. 80%)
(2) For the PreCharge:
- EVTargetVoltage (The battery voltage)
- EVTargetCurrent (The target current for precharging. Fix value of 1A should be fine.)
(3) For the charging loop (CurrentDemandRequest):
- EVTargetCurrent
- EVTargetVoltage
- ChargingComplete (to indicate finished charging)
- BulkChargingComplete (to indicate that the "fast charging phase" is finished
- RemainingTimeToFullSoC and RemainingTimeToBulkSoC: To show to the user how long the charging will take.

For closing the contactors, the voltage of the battery and of the CCS inlet need to be compared, and if the difference is small enough, the contactors can be closed. In the planned setup, this relies on the battery voltage on the "extended" Chademo CAN message, and on a physical measurement of the inlet voltage, which can be either in the vehicle or in the adapter.

For the charging loop, the targetvoltage and targetcurrent are provided on the CAN I guess, they just need to be routed to the CCS state machine.

For stopping the charge, a button on the adapter could be used, or is a stop-signal provided from the car on CAN?

[johu]

Ok great. Yes I think I'd just invent stuff or stick it into the additional can message
- SOC - available via CHAdeMO (will use cdm from here) by dividing reported through maximum capacity
- EVMaximumCurrentLimit - min(ChargerLimit, 200A)
- EVMaximumPowerLimit - min(ChargerLimit, 360*200 W)
- EVMaximumVoltageLimit - available via cdm
- EVEnergyCapacity - available via cdm or just set to 60 kWh or so
- EVEnergyRequest - fix to x kWh
- FullSOC/BulkSOC - yes 100/80
- EVTargetVoltage - provided by extra can msg
- EVTargetCurrent/Voltage - from cdm
- ChargingComplete - from cdm charge enable bit
- BulkChargingComplete - soc > 80
- RemainingTimeToFullSoC/... - from cdm (I provide some maximum value because too little time will shut down the charger)

I usually stop the charging session on the charger but I can also drop the charge limit to 0A in the car to disable the charge allow signal. Wouldn't want a button that everyone can press. Voltage, hmm. Does the charger report its port voltage? If so I'd just compare that to the BMS reported battery voltage provided via extra can message. Would like to try and avoid a physical voltage measurement but if really necessary it's not so hard to do of course.

[uhi22]

Indeed, during the PreCharge phase the charger provides the actual voltage in dinPreChargeRes.EVSEPresentVoltage. At least this signal is defined. I've never tested this. I understood the specification in a way, that the vehicle is responsible to measure the inlet voltage physically. However, relying on the EVSEPresentVoltage could be the solution for a "minimal effort approach".

[Zapatero]

Subscribing to this topic and following with great interest!

[uhi22]

Just for completeness: Johu charged the Touran with the CCS to CHAdeMO adapter: viewtopic.php?p=58005#p58005. It's a special setup which requires additional CAN message on the CHAdeMO, to provide the actual battery voltage. This makes it possible to have a simple HV wiring, just straight-through the adapter. The more universal approach would require a diode or contactor(s), and physical voltage measurement in the adaptor.

[johu]

Yes we (celeron55, me) thought about locking out the CCS socket, then briefly engaging the port relays to take the measurement. So you'd plug in CHAdeMO first, then CCS on indication.
A diode won't be feasible, it generates like 0.5-1W/A, so 50-100W @ 100A. Hard to cool. Extra relay - meh

[mikeselectricstuff]

A diode won't be feasible, it generates like 0.5-1W/A, so 50-100W @ 100A. Hard to cool. Extra relay - meh

Might MOSFETs or IGBTs be feasible?

[johu]

IGBT I'd say not, it always drops 1.5-2.5V so even more loss than a diode. Low R_on mosfet perhaps.
Here's a SiC one for a hefty 70€ https://www.digikey.de/de/products/deta ... S/11587031
9 mOhm, so 100²*0.009 = 90W - go figure
I think I'll leave it to a product designer to come up with a plug-in inhibition device that makes sure you first plug in CHAdeMO and only when voltage measurement is done and port relays are open are you able to plug in CCS. Like a little flap before the power pins, also makes sure you don't stick you fingers in there during voltage sense.

[uhi22]

There are some ukrainian videos, which show a quite small adapter, for me it looks passive on a specially prepared car.


and

[johu]

You think they repurposed one of the CHAdeMO pins as CP? And all the CCS magic is in the car?

[uhi22]

Looks so. Cannot imagine that they hide a battery and electronics in this small adapter.

[WladKo]

Hi,

ChargeSpy developer said in Telegram group, their adapter can work with Leaf or other car after 2015 which supports V2L. I guess, they using CHADEMO pin3 (12V to V2L adapter) to power up internal electronics.

[2fast4u]

Is it only the 12v on pin 3 that is needed or is it some other V2L features that is required for the adapter to work?
@JOHU: The ccs -> chademo test setup you had in the trunk seemed to just be some wiring and a can bridge fixing the communication.. Is that correct?

I assume that if you scrap all the locking mechanisms that should be there and put your faith in the user connecting/disconnecting in the right sequence when proper status is achieved (and not disconnect when charging) the actual adapter could be very small, cheap and easy.

[hwthomas]

Does anyone have an idea of the price for these adapters? Might they be a source for a cheap(er) CHAdeMO plug and CCS2 socket?

I've been following this topic with interest, with a view to using an RPi4b with a Waveshare 485 CAN HAT to talk to a Nissan Leaf (2021), but the biggest problem is the price of the CHAdeMO plug (quoted at £750+ from Germany or China). Or does anyone have a source for 3D-printed ones?

[WladKo]

Does anyone have an idea of the price for these adapters? Might they be a source for a cheap(er) CHAdeMO plug and CCS2 socket?

Hi,
It cost 400$ for their clients (GBT/DC to CHADEMO port replacement service). But how much it cost separately you can ask directly here https://t.me/chademoforchina or here https://www.youtube.com/@FastChargeIsFuture

Files for 3D printing of CHADEMO plug is here https://www.thingiverse.com/thing:121581 But main issue of 3D printed plug is how to make pins. Follow this link you can find some variants.