New on-board Charger/BMS- doing a nice job of it.

[EvGoRetro]

New guy here. Please point me to an existing thread or topic or website (or a book) if that's more efficient...

I'm planning a BMS/onboard-charging system for a vintage car conversion. This is a bit bigger than the motorcycle conversions I've done previously.
Sure, I can easily just throw together a Frankenstein solution, but I want some advice on doing a real nice onboard charging system around about 6.6 kW.

My questions are like this:

• Would someone share their experiences of installing and using a decent 6.6 kW on board charger- Maybe Elcon HK-J series or similar? (If no experience, then a decent opinion will do!)

• Is it worth the trouble getting all the CANbus working between the charger and the BMS? Or just keep it dumb?

• Are matched Charger/BMS systems a 'thing' yet?

• What do I need to know about connecting to the big wide world of Public Chargers? (Do I need to 'talk' with them? Or does it just 'plug in'? )

Battery pack: 96 V, 280 - 310 Ah, ~27 kWh, LifePo4, max charge rate: 0.5C (~13.4 kW). I'd be happy with 6.6 kW
Current draw: 150 A (nom.), 340 A (peak)

[coulomb]

I can partly answer some of your questions.

• Would someone share their experiences of installing and using a decent 6.6 kW on board charger- Maybe Elcon HK-J series or similar? (If no experience, then a decent opinion will do!)

I don't know if I'd class the newer ultra high frequency, ultra compact Elcon chargers as "decent". One user had a lot of trouble with them, I thought it was @Paulvk but I can't find the post now. [ Edit: Actually it was Paul9; see this post. ] @jonescg used one in the Prelude conversion, and it seems to work OK, as long as the power source is capable of about 30 A.

• What do I need to know about connecting to the big wide world of Public Chargers? (Do I need to 'talk' with them? Or does it just 'plug in'? )

There is a small amount of "talking" required; you can't "just plug in". There is a small module, the AVC2, which is designed for doing this "talking" for DIY conversions, but there seem to be problems. See Chris Jones' posts on the Prelude conversion, starting about here. You might be able to read earlier posts and find the post where he selected the Elcon; I could not quickly find it.

There is little hope of connecting a conversion to a fast (50 kW+) DC charger. The handshaking is very complex, though Damien McGuire was attempting it using used BMW parts. Note that many DC fast chargers won't charge a battery under 200 V, though I believe that the fairly common (at least in Australia at present) Tritium RT 50 kW will charge from 50 V upwards. A 27 kWh battery probably doesn't need DC fast charging, even a higher-end vintage conversion. But the ability to charge at public type 2 "chargers" would be good in a higher-end conversion.

[EvGoRetro]

You're a champion, Coulomb.
That AVC2 info is what I needed to know - and I did read your comments in the links)

Still keen to hear about any recommendations for a decent On-Board Charger around 6.6~7 kW. Or other people's experiences with OBC's.

Anyone used an Orion BMS? https://www.orionbms.com/products/orion-bms-standard/
Or can suggest a decent alternative?

I'm always happy to listen to experience... its a much cheaper way to learn.

DC Fast Charge? Nah, not for me!

Proposed Battery pack: 30s LiFePo4, 96 V, 280 - 310 Ah, ~27 kWh, max charge rate: 0.5C (~13.4 kW). I'd be happy with 6.6 kW OBC.
Expected Current draw: 150 A (nom.), 340 A (peak)

[jonescg]

I installed the TC charger in the Prelude and it's been working reliably, however if the ZEVA BMS processes a corrupted data packet, it can for some odd reason reset the BMS which means the charger loses some comms. It appears to continue charging though.

[4Springs]

My questions are like this:

• Would someone share their experiences of installing and using a decent 6.6 kW on board charger- Maybe Elcon HK-J series or similar? (If no experience, then a decent opinion will do!)

• Is it worth the trouble getting all the CANbus working between the charger and the BMS? Or just keep it dumb?

• Are matched Charger/BMS systems a 'thing' yet?

• What do I need to know about connecting to the big wide world of Public Chargers? (Do I need to 'talk' with them? Or does it just 'plug in'? )

I've just installed an Enpower charger, purchased from Oz DIY. Mine is a 3 kW version, I don't know if they do a 6.6 kW, but I assume you could put two in.
I control it with a Thunderstruck EVCC (EV Charge Controller), which talks CAN to it. I was a bit concerned that the Thunderstruck EVCC would only talk to a Thunderstruck charger, but it works fine with the Enpower. The other charger I looked at was a TC Charger, which appears to use the same CAN interface. I went with the Enpower since it was about the same price as the TC Charger, but there is a local distributor. The EVCC can control up to three chargers.
The EVCC takes input from a BMS, and can talk CAN, but in my case I kept it dumb with a simple loop control.
The EVCC also lets me use a Type 2 AC socket (it adjusts the charger control current to suit the EVSE). This means I can plug in at public chargers (AC).
It looks like Thunderstruck are now selling an MCU (Master Control Unit) which does charger, BMS and Type 2 socket all in the one unit.

I haven't quite finished yet, but the car is charging nicely from the two EVSEs that I have here. Once finished I intend on writing up my system so that others can copy it. In the meantime I've been making videos and posting to my Youtube channel. You can see the first one here: https://www.youtube.com/watch?v=S0_l13UUyPc&t=606s

[EvGoRetro]

Ta Jonescg1

Always keen to hear:

• Please share your experiences of installing and using a decent 6.6 kW on board charger- any type.

• Is it worth the trouble getting all the CANbus working between the charger and the BMS? Or just keep it dumb?

• Any other good or bad experiences connecting a home-built car to the big wide world of Public Chargers? )

... or am I just worrying about it all too much?

[EvGoRetro]

Hi 4Springs,
Yeah that Thunderstruck MCU (Master Control Unit) looks pretty trick- so much functionality. I think I've found a solution.

[Paul9]

I had a lot of trouble with the 3.3kw Elcon chargers. I think the post to which @coulomb refers is the post I wrote explaining my problems. Ill repost it as follows for info:

" First problem is that the connectors are 4 pin, pin and socket connectors. The female connectors do not fit snugly onto the male connector - they wobble! Even though they are locked in they still wobble.

Secondly the female lugs that go into the female connector don't stay in. If you turn the female connector upside down and tap it, the lugs (and any wire attached to them), fall out of the connector. These lugs are also very thin. Less than 2mm in diameter. Don't drop them on the garage floor as, if your garage looks like mine, you will never find them. And TC only give you 8 pins in total - no spares.

Thirdly, neither the female connectors nor the lugs that go in them are available in Australia. I have tried some online stores suggested to me by "Coulomb" and they have advised they do not have them.

Fourthly the User Manual is less than clear in regard to which hole in the female connector receives which wire. Emails with "Coulomb" and a number of emails to TC in China have, I think, cleared this up.

As a result of the above I managed to blow one of the connectors up (the DC OUT connector). A loud bang accompanied by a large shower of sparks and melted lugs was the result. Despite being very careful that the right wire went in the right hole, I may have stuffed up my connecting somewhere, so I am not laying all the blame necessarily on the charger. End result is one stuffed $1,000AU charger.

I have been told persistence is a virtue so I got out the other new charger and wired it up without the female connectors and insulated the living daylights out of all the wires. I powered the charger up and it just sat there. The fan didn't spin and no LED lights. But I had achieved something - no explosion! About the same reaction as if I had wired up a house brick.

The old PFC TC Chargers using IEC connectors were just plug and play. The only other thing I have noticed is that the new 3.3kw TC chargers from the USA (based only on photos on their websites) already appear to have wired up the connectors for you and have the wires running out of the connectors so you only have to connect the wires.

I am fully aware than a number of my problems with my EV have been a result of my own stupidity so I took my "good" TC Charger ("good" as in not the one I blew up) over to my electrician brother's place to check my wiring and test the charger. Even though my crimping of wires to lugs was fine, he always likes to solder things, so he rewired all wires with solder.

We then connected up the AC IN as per our understanding of the manual, the DC Out as advised by TC in China, and connected the 12v+ to the enable line as I don't use CAN. He then put a multimeter on the DC out and absolutely no reading. The fan didn't spin and no LED lights showing error messages."

The above is why I prefer to use the KPES chargers."

Regards
Paul

[4Springs]

I had a lot of trouble with the 3.3kw Elcon chargers.

Do you mean TC Chargers?

[Paul9]

Sorry yes I do mean TC charger.