DIY compatibility with public charging stations

[harrisonpatm]

Going through the planning process for my next e-moto build, and I'm considering making it a huge battery, to combat range anxiety. If space allows. Then when I think about how big it is, I realize that it's gonna need a heck of a charging setup. Currently my approx 5kwh battery can be charged on a couple solar panels in 2ish days, and I also got a relatively cheap AC charger from aliexpress that I use if I need it charged a bit faster. But by faster, I still mean 7-8 hours. Perfectly fine for now. But I really am looking in the range of 9-10kwh for the next one, as insane as that sounds, and I realize that it might be beneficial to have this capable of charging at public EV charging stations. Especially since I will likely be building this for someone else, who may want it, even though I don't.

So far I think what I need is this, a J1772 to NEMA 5-15:
https://alienrides.com/products/220-volt-ev-charger-adapter
Then I should be able to get 240VAC out of a charging station. Next, I need to find a suitable charger that accepts 120-240VAC, and outputs my battery's required DC voltage, preferably with plenty of power, somewhere in the range of 3000-6000w. I would need to mount that charger within the motorcycle build itself, and wire/plug it into the output of the J1772-to-Nema adapter. So it would need to be pretty durable, being on the motorcycle all the time. And wire the DC output to the battery. With proper wire gauge and fusing, of course.

Then for home charging, I think I need a 120 or 240V Nema to J1772 cord. So that the owner can still use home charging, and plug into their home outlet, which can connect to the bike via the same charging port. Which just again puts power into the onboard charger. That way I don't need to build a second charging port for home charging. Like this:
https://www.amazon.com/Lectron-Bundle-Electric-Vehicle-Charger/dp/B08XKDNNVK?th=1
... and there are Level 2 or 240V connectors as well, if the owner has access to 220v near their parking spot.

Does this sound like I have the concept right in theory? Any major parts I'm missing?

 

[Tony01]

Depends on your battery specs. Most round cells can be charged at .3-.5c, pouches usually 1c, so 5000w on a 5kwh pack. Most J-plugs are 6.6kw, and between 3.3kw and 7.3kw. If your charger is 110/220 capable I would put a standard male 110v socket somewhere on the bike so you could just plug an extension cord.

The cheapo ones like the alien rides have only the pilot circuit and no proximity pin use (latch on j-handle). And you can find the cheap one cheaper at https://www.evseadapters.com/products/j1772-ev-adapter-for-ebike/

But on those cheapies the com circuit which is simply a resistor and diode, tend to fail sometimes. So I use this little board with a J-plug you wire up yourself from AliExpress. I was able to fit 10awg cables in mine. https://www.electriccarpartscompany.com/J1772-Active-Vehicle-Control-Board-AVC2

When out riding an emoto power becomes less of an issue than charging fast. There are batteries out there rated for a 2-5c charge which means under 30 minutes to full. I have some here that wouldn’t even get maxed with two j-plugs in parallel. I may find that 7kw charging is enough however.

 

[harrisonpatm]

I understand that about the battery and charging rates, I'm just asking whether the actual hardware I linked is usable. Just want to try to wrap my head around the actual equipment involved.

 

[john61ct]

Be aware some networks / jurisdictions may reserve their use for cars only.

Or in future ban DIY rigs once a few fires occur

 

[harrisonpatm]

Be aware some networks / jurisdictions may reserve their use for cars only.

Or in future ban DIY rigs once a few fires occur

Ugh. I didn't think about that, and it's pretty annoying that you're probably right.

 

[chuyskywalker]

Depends on your battery specs. Most round cells can be charged at .3-.5c, pouches usually 1c, so 5000w on a 5kwh pack. Most J-plugs are 6.6kw, and between 3.3kw and 7.3kw.

That kinda sounds like you're implying that the battery pack needs to handle up to that wattage, but that's not the case. To be clear, the charger will set the wattage, not the station (up to whatever the station supports).

Be aware some networks / jurisdictions may reserve their use for cars only.

Right now, with level 1/2 J1772 plugs there is no way to know if what's plugged in is a car, truck, or toaster. Like others have pointed out, the whole mechanism is really just a giant 240AC plug that has a few pins for closing a contactor to allow current flow.

Only once you get into Level3 (direct dc charging) there is an actual communication protocol; but even that is very generic at this point merely allowing the charger and station to negotiate what voltage/amperage the pair engage.

You're not wrong that some companies have policies around this (IANAL; which one may choose to ignore). Maybe in the future tech to enforce it with some kind of verification system may exist, but right now that's not the case. (Such a system will need all the auto makers and charge providers to get in on some kind of identifying, centralized authorization system which seems...complicated to make happen.)

Just want to try to wrap my head around the actual equipment involved.

I think you've pretty much got the right of what you need.

 

[harrisonpatm]

You're not wrong that some companies have policies around this (IANAL; which one may choose to ignore). Maybe in the future tech to enforce it with some kind of verification system may exist, but right now that's not the case. (Such a system will need all the auto makers and charge providers to get in on some kind of identifying, centralized authorization system which seems...complicated to make happen.)

Unfortunately I think at this point, the only tech needed to keep only certain vehicles at charging stations is a person to tell on you. Hopefully most people would be cool about it, but it just takes one a-hole to ruin it for others. On both sides.

 

[Tony01]

I understand that about the battery and charging rates, I'm just asking whether the actual hardware I linked is usable. Just want to try to wrap my head around the actual equipment involved.

The hardware linked is fine just get the one for $90 no difference. J plugs are just a fancy 240v plug with a resistor and diode from pilot to ground. You could wire it yourself with a blank plug from aliexpress for $40.

The J plug is the easy part. Finding chargers and battery cells for the charge rating is the hard part. Big battery is only part of the range anxiety remedy, you must be able to fill it fast.

 

[harrisonpatm]

Indeed, that's the downside to such a big battery. For comparison, my modest electricity usage for my house every day is 10kwh. When I imagine making a 10kwh battery just for a bike, I picture my electricity usage doubling. Don't get me started on a full sized electric car.