V2V, V2H, V2X - what's the holdup? Where are the deets?

[Jerm]

Is this minor detail still relevant? If so, add another $3900.

Wow... Hadn't seen that yet. Definitely still a win for me, but I didn't know about the battery. Nice to see confirmation on the inverter component requirement though.

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[BigSkies]

I imagine potential warranty issues are holding the manufacturers back as well.

If they warranty a battery pack for X,000 miles, does that still apply if someone powers their house with it every day? Can they commit to battery replacements if people are using them that way?

They probably don't have the data to answer that question. And that could be a really expensive hit if it did create a need for early replacements.

 

[SANZC02]

I imagine potential warranty issues are holding the manufacturers back as well.

If they warranty a battery pack for X,000 miles, does that still apply if someone powers their house with it every day? Can they commit to battery replacements if people are using them that way?

They probably don't have the data to answer that question. And that could be a really expensive hit if it did create a need for early replacements.

It would be interesting to see a study of that. Would like to see how much that use case degrades the battery. We know powering a house is easier on a battery than running an EV as one of the second life use cases for old EV batteries is storage.

I do power my house from a Tesla Power-wall daily from 4PM to 9PM because of our peak rates of 57 cents in winter and 62 cents in summer, it is using 30%-50% of the battery every day and it has a 10 year warrenty.

 

[Jerm]

I imagine potential warranty issues are holding the manufacturers back as well.

If they warranty a battery pack for X,000 miles, does that still apply if someone powers their house with it every day? Can they commit to battery replacements if people are using them that way?

They probably don't have the data to answer that question. And that could be a really expensive hit if it did create a need for early replacements.

Good question- but then, that's a consideration they should have made before hyping the feature and compatibility plan. I purchased with an eye on this coming in the future.

 

[Indy avocado]

In any case, I don't even have the details yet on how it would work. I have so many questions. Straight up DC I assume, but how fast? Does it slow if charge levels aren't far apart? Possible to charge past equalization point? Or maybe I've got that all wrong and there's an inverter(s) involved?

Just a thought. Creating standards for V2V across manufacturers is difficult, but it would be cool if Rivian enabled a V2V capability for its vehicles, and then via the app allowed people to opt-in to a user-supported emergency charge capability.

As you might expect, you can't just connect the batteries together with a "jumper cable"

If you just connect the batteries together, you'll get a "50V short circuit" as far as the batteries are concerned - There would be a powerful arc when connecting or disconnecting, and you could see 100's of amps with absolutely no way to control it. The batteries and wires would almost immediately melt unless they were within a few % state of charge.

So we need to manage the power transfer actively. We can't "just" current limit the transfer - the only way to do that without just throwing massive amounts of power away as heat is active power control.

Here's the main problem:
DC Fast Charging works by having a very powerful, LARGE, and EXPENSIVE power conversion between the power source and the vehicle. When you're charging, the DC pins of the CCS connector are *directly* connected to the battery pack, with the only "controls" the vehicle has are a *request* to the charger for a certain amount of current and a physical disconnect in case something goes wrong.

What that DC fast charger is doing:
Converting 208, 240, 277, or 480V AC power to DC
Boosting or dropping voltage to match vehicle/battery
Limiting current to match what the vehicle/battery can accept

The 2nd and 3rd steps need to happen again if you want DC V2V charging.

Even a "low power" 30kW DC charger is expensive ($20k), heavy, and large. Almost 200lbs and several cubic feet of volume:
https://www.boschevsolutions.com/charging-stations/ev3000-30kw-dc-fast-charger

So, for now, the most sensible option is to re-use the existing vehicle charger that is capable of accepting 120/240V AC and converting it to battery voltage. If designed correctly this could also be used to convert battery voltage to AC power, or (theoretically more easily) DC power. In the case of the Rivian, we have about 12kW of power conversion capability. This may very well decrease if the "job" changes to output instead of input.

Other brands offer higher power AC charging capabilities (Ford, Porsche, Audi) with up to 80A or 19kW. Those are somewhat expensive upgrades ($1800 for the Porsche one).

I think that if it was mandatory / accepted that all vehicles supported bi-directional charging, the cost of these components would rapidly fall and become a non-issue for the <20kW range. But the "fancy" high power voltage conversion circuits are still pretty novel. I'm sure we'll see precipitous price drops, but there's also a floor given how much material is required to handle that much power/current. Probably half of the cost of the Rivian home charger is the 20' of really high quality coper cabling in the wire. It would cost you easily $200 to buy just the wiring.

Anyway, it was a bit of a ramble to try and explain why it's not here yet, why it might not be trivial, but also why there should be hope

 

[Jerm]

That's kind of level I was expecting, but at the same time, I don't feel that bad for having expected something to be further along by now, considering the way it was bandied about 4 years ago...
https://www.autoblog.com/2019/06/08/rivian-confirms-v2v-charging-auxiliary-batteries/
I wouldn't blame someone for expecting more than there is at this point, complex or not. Don't want expectations, don't make promises, you know?

 

[Rivinski]

I’m surprised nobody’s jumped on the announcement from RJ on IG AMA that they’re working on a bidirectional charger for existing vehicles. No idea when it’s actually going to come out but I’m all in once it does.

 

[Cosmacelf]

I’m surprised nobody’s jumped on the announcement from RJ on IG AMA that they’re working on a bidirectional charger for existing vehicles. No idea when it’s actually going to come out but I’m all in once it does.

All he said on the AMA is that they are working on it, which is what we knew before the AMA. Honestly, RJ should have been born a politician. That entire AMA provided zero new useful information.

 

[Rivinski]

All he said on the AMA is that they are working on it, which is what we knew before the AMA. Honestly, RJ should have been born a politician. That entire AMA provided zero new useful information.

Fair, but hey, he was standing in front of some random equipment so it’s more real now.

The overhead cam and rear screen functionality comments were new to me, but not really groundbreaking. It would be great to see their actual roadmap but people wouldn’t be able to handle the standard delays that come with developing hardware and software.

 

[SANZC02]

I do not have an instagram account, does anyone actually have a list of the questions and answers? I saw a couple but have seen references to a couple of others but not the question and answers.

 

[connoisseurr]

The AMA with RJ eluded that the features will be activated once Rivian builds their own ”bi-di” charger. That’s great and all, but other manufacturers will most likely beat them to market with equipment. I’m hoping this is the case for Enphase, and their bi-di charger.

 

[LevelHeaded]

Getting tired of looking at social media posts of dead battery EVs on the road with a portable generator attached to mock them... not sure why people feel compelled to video any EV that runs out of fuel but not ICE

Lol, I’ve never seen such a post in any of my feeds. Who in the world are you following!

 

[godfodder0901]

I do not have an instagram account, does anyone actually have a list of the questions and answers? I saw a couple but have seen references to a couple of others but not the question and answers.

I think they have it posted on their youtube page.

 

[SANZC02]

I think they have it posted on their youtube page.

Thank you

 

[CharonPDX]

The AMA with RJ eluded that the features will be activated once Rivian builds their own ”bi-di” charger. That’s great and all, but other manufacturers will most likely beat them to market with equipment. I’m hoping this is the case for Enphase, and their bi-di charger.

Can’t wait to replace my JuiceBoxes and Powerwall with Enphase’s solution, as I already have their solar panels.

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