[wb4apr]

I want to put the EVSE in the car and only have a plug hanging out so I can charge easily from an extension cord. Without hassling with the J1772 cord and plug handle.

Where can I get to the five j1772 wires easiest inside the car?. I'm new to the Volt but have done Plugin conversions of 3 salvage TOyotas, so all I need are the schematics and where to look. I also want to hack into be able to put some solar charge into the HV battery directly. Is there anywhere to get access to the HV terminals of the battery that is outside of the battery pack itself? Like the prius,, I could solar charge the HV battery because once the BMS cover was off, one could tap directly to the HV contactors easy enough.

If this is not the right forum, where are the VOLT hackers? I'd rather find an email reflector for such chats.
thanks
Bob
bruninga at usna dot edu

 

[Loboc]

Other than learning how these systems work, I don't see a practical solution.

How is a J1772 design more hassle than a raw extension cord? It is certainly less safe to bypass J1772 interfaces. Even simple things like cable management and strain relief could be problems.

Direct DC charging might be worth pursuing, but, at what cost to re-invent SAE standards? Off-the-shelf GM parts might be a way to go such as Bolt or Spark DCFC units as a starting point.

 

[wb4apr]

It is not less safe. Both the standard J1772 portable EVSE and one I intend to install in the car, both interface to the grid via the same 3 prong 120v standard plug. ANd both EVSE provide all the identical safety features. Its just the one inside the car will have a 15' retractible cord. See how I did it on a Leaf: google for "charging-DIY.html"

 

[srmarti]

Doing that will make it difficult to use L2 charging. I suppose it wouldn't be all that hard to install the ESVE hardware in the car, but I don't see a compelling reason why that's worth the effort.

Your solar system input to the battery still has to be regulated somehow.

 

[Raymondjram]

You can buy the Chevy Volt Service Manuals, but getting into the battery directly is only possible at the battery terminals (which is under the floor) or at two points in the engine bay: the battery cable terminals at the controller, or the A/C compressor terminals which gets its power from the battery. I am an EE with several years working with HV systems, but I will not risk a functional Chevy Volt (which is still under warranty) just to charge it differently.

Bypassing the EVSE is possible just by fooling the SAE J1772 signals at the on-board charger (AC-DC converter) which is also attached to the battery, or by moving the EVSE control circuit and indicators inside the body. Both are risky, but if you want to do this, it is your car and your life.

 

[edk-austin]

Plugless attaches their parallel wireless charging receiver internally to the J1772, but I don't know where specifically.

Attaching solar directly to the HV battery is certainly feasible, as long as you have a voltage limiter. You REALLY don't want to EVER get above 4.2V per cell on Lithium, Volt never gets close to that (never does 100% SOC). But solar also likes to operate at a Vmpp, for best output, so it's worthwhile to have a real lithium battery charger. Which would parallel the GM OBCM. The GM OBCM won't operate unless it can pull a minimum of 6A in the 100-130VAC range (per AC leg).

 

[llninja]

Thank you for your service to our country. I was about to say don't do it, you'd be crazy to mess around with the innards of the volt, but you left your email in the signature and a quick google search reveals you are an EE, have done lots of EV projects, and probably the forum member you want is WopOnTour. He works for GM and frequents this site from time to time with his wisdom. Try to PM him to see if he can answer your questions.

But from a practical standpoint, I can't see how putting some solar panels on the roof of the car can really help range significantly, unless you have some contraption to open up a giant array like satellites do, or you are willing to wait for days and days and days between charges. I'm intrigued by your publication about charging beyond L1. I wonder what that's about? Are you using 110V to somehow charge faster than the 8-10 hours a normal L1 charger produces at 12A?

 

[hellsop]

Thank you for your service to our country. I was about to say don't do it, you'd be crazy to mess around with the innards of the volt, but you left your email in the signature and a quick google search reveals you are an EE, have done lots of EV projects, and probably the forum member you want is WopOnTour. He works for GM and frequents this site from time to time with his wisdom. Try to PM him to see if he can answer your questions.

But from a practical standpoint, I can't see how putting some solar panels on the roof of the car can really help range significantly, unless you have some contraption to open up a giant array like satellites do, or you are willing to wait for days and days and days between charges. I'm intrigued by your publication about charging beyond L1. I wonder what that's about? Are you using 110V to somehow charge faster than the 8-10 hours a normal L1 charger produces at 12A?

Annapolis gets about 4kwh per square meter per day ideal. The roof would probably be good for about 2 square meters, minus the usual "not optimal" orientation (60% of ideal), plus efficiency of flexible panels (to not add tooooo much drag) power conversion and the back of my envelope says we can net about 750 watt hours per day from the roof of the car. So it ain't nothing. But still probably more effective to roof over a parking lot and put J1772s in the stalls instead.

I did those numbers a while ago, and most place in the US will yield about 5 kwh per parking stall's worth of panels during typical "business hours" on average. Add in some net billing for non-busy hours and days and/or diversion to the building's power input, and you're looking at free Level 1 charging for an entire parking lot forever for the cost of the installation.

(And that's why I don't pay much attention to the "Our electric infrastructure would crumble if everybody drove electric cars" pearl-clutching. That's only if you don't do anything about it.)

 

[canehdian]

wb4apr, I'd be curious to follow your progress if you could hook up solar via the existing J1772 charging connections and charge directly with DC (as opposed to DC -> AC -> DC that some members have set up).
I know one member experimented a bit, but obviously not a fully working setup.

I did those numbers a while ago, and most place in the US will yield about 5 kwh per parking stall's worth of panels during typical "business hours" on average. Add in some net billing for non-busy hours and days and/or diversion to the building's power input, and you're looking at free Level 1 charging for an entire parking lot forever for the cost of the installation.

(And that's why I don't pay much attention to the "Our electric infrastructure would crumble if everybody drove electric cars" pearl-clutching. That's only if you don't do anything about it.)

And also overnight power - if everyone charged in the dead of night, we (my province) could add a ton of cars (at least 700 000+) with zero extra grid capacity required. And that's not counting 'bonus' sources, like wind. Only nuclear and hydro installed capacity that's always there.

Local neighbourhood distribution is another story - but on the whole, we have tons of power available if used smartly (if you don't need to charge at 5pm, don't).

 

[Jim in Tucson]

I'm intrigued by your publication about charging beyond L1. I wonder what that's about?

Google search for the document by title. It's out there...

 

[Kuikka]

Any updates?