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Comment by burger_moon | Hacker News Reader

Can you recharge these on a normal gas generator? Something like a Miller engine driven generator[1] could probably do it but those are $$$ for the average joe. I only ask because a lot of people trailer their rock crawlers/mudders to more remote areas to go play and have fun, but when the electricity runs dry you'll need a way to power it back up. This thing looks like it'd be a lot of fun not only for daily use but also for backwoods offroading.

[1] https://www.millerwelds.com/equipment/welders/engine-driven/...

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Here's a thread on doing this with a Nissan Leaf.

http://www.mynissanleaf.com/viewtopic.php?f=26&t=5792

From that and similar threads on Teslas, the caveats seem to be:

- Need a sine wave generator vs the cheaper square wave ones.

- Some cars allow you to adjust the current draw to match lower output generators, some don't. Cheap generators probably don't output enough current.

- You have to tie neutral to ground and use a real ground rod.

I'm guessing that these Bollinger guys won't stand for any of that sissy "pure sine wave" or "ground rod" crap, and would let it charge with just about anything that puts out a voltage.

Not that a pure sine wave generator isn't superior to noisy, cheap square wave 'inverters' or that grounding a charging EV is a bad idea, but that's the attitude I have picked up from seeing ground pins cut off of various farms and tools. I'm sure their EEs would make sure that the thing was double-insulated and otherwise capable of dealing with this need.

Regarding current draw, it should be possible to regulate it with the external equipment if you really need it. All US EVs support J1772, and the J1772 plug tells the car how much it's allowed to draw. Some cars let you tell it to draw even less, but it will always respect the equipment's limiter.

For a simple example of this, Tesla's mobile connector will signal different maximum currents depending on which outlet adapter you have on it. If you have a NEMA 14-50 adapter it'll tell the car to draw up to 40A, but if you swap in the NEMA 5-15 adapter it'll tell the car to only draw 12A.

> - Need a sine wave generator vs the cheaper square wave ones.

That seems really weird; I'd expect that the big charging station you install in your garage would convert from home AC into some high-current DC. Batteries don't actually charge on AC, do they?

Not directly, no. But electric vehicles convert AC since that what consumers have easy access to.

And their rectifiers expect nice sine waves.

J1772 plug (the one that every EV has) is an AC connection and there is a converter in the car that converts it to DC.

The super charge ports (CHAdeMO/CCS/etc) use DC power and are basically direct hookups to the battery.

https://en.wikipedia.org/wiki/SAE_J1772 https://en.wikipedia.org/wiki/CHAdeMO

I think some of the newer one have a high speed DC charging option. I think the Chevy Bolt has a DC option.

If you're carrying around a generator, you may as well carry around an internal combustion engine though?

Well in the case I presented the generator would stay with your rv/ or whatever you're towing this thing around with, as I explained, a lot of people use these types of vehicles in more remote areas. You don't really need the engine for going out during the day, only for recharging at the end of the day. This means a much simpler design and less weight to drag around. A generator is much easier to service and maintain that an engine attached to the vehicle.

Of course I'm talking about a small niche of customers in an already small niche of people that buy 4x4s.

Is that always true though? I could see doing that for longer trips (rare) and leaving it at home for the remainder of the 90% of trips.

I'd bring it while towing something heavy as a safety net. Towing will affect the range in ways which aren't easy to calculate with hilly terrain even if you know the weight of the trailer + cargo.

Not necessarily - you might only charge using the generator every 20th cycle; the other 19 you might leave it at home (or in your other vehicle, or whatever).

That's the idea of a hybrid, no? For a lot of the places I'd want to go camping in a truck like this, I'd be likely to want a generator anyway, so I might as well trickle-charge the vehicle back up whenever the power is on.

That was my thought. Looks to be plenty of room in that front trunk for a generator to make this a not-so-poor-man's hybrid.

I think the future really will be a hybrid - at least have a small generator to get out of emergency or stuck situations. I'd much rather drive at 10mph somewhere than need a flatbed pickup.

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