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Will’s video & the holy grail of EV/hybrid vehicles as simple backup generators

PriusFan

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It’s amazing to me that Will posted this video nearly two years ago and the portable power industry seems not to have responded.

As far as I know every EV/hybrid vehicle with a traditional 12v battery, in addition to a traction battery, can attach an inverter and pull at least 1000 watts continuously (as least 1000 watts is the accepted wisdom for the Prius - I own a Prius). As Will illustrates when the vehicle is left turned “on” the traction battery will provide the necessary charge to maintain the charge under load of the 12v battery. Problems only develop if you run out of traction charge on a EV or gas on a hybrid.

Will explains that if you are off grid and have a series of miserable solar days you can use your EV/hybrid to recharge your battery bank.

The portable power station manufacturers have successfully made solar charging central. That’s as it should be. They often also ship cigarette lighter chargers which charge at the 150ish watt limits of that port. It seems no one is selling a portable power station charging cable that connects directly to the 12v car battery like Will does here. As Will illustrates using the 12v battery directly will charge a power station much more quickly than the cigarette lighter.

These portable power stations already often have significant solar DC input rates. And at least one portable power station permits solar charging of a maximum of 800 watts and has a 12.5 volt minimum input requirement at the bottom of it’s solar input range. The MPPT is built in. (It charges from the wall at 1200 watts.)

I may be missing something very important but given the 12.5+ volts we generally see Will report in the video could a portable power station like this simply be connected to the EV/hybrid 12v directly? Eliminating the losses of the DC to AC inverter or the DC to DC converter Will references in the video? If your goal is immediate AC power one uses an inverter as Will does here. But if your goal is to charge a 12v DC system it would be ideal to do it directly without these DC to AC to DC or DC to DC series of conversions. (I’ll note here that very few portable power stations are 12v systems - most are 24v or 48v and their voltage input ranges fall above 12 volts. To accomplish what I am describing here would require a voltage booster to be built into the cables to these systems such as Will references. And manufacturer liability may be a big reason this option seems not to be offered.)

However I would think that when manufacturers create portable power stations that can easily be connected directly through one cable to EV/hybrid 12v batteries for high speed charging of DC systems they will have a hot product on their hands. Particularly if it can simultaneously discharge nearly the DC input wattage as AC through the built in inverter (instead of, as Will does, effectively having an AC inverter charging another AC inverter in the portable power station).

Ideally we avoid fossil fuels altogether but if an EV/hybrid backup makes people more secure about investing in solar, or more likely to buy an EV/hybrid then that seems to be a win for the environment.

But time for your advice. After watching Will’s video can a direct cable be created as easily as I suggest? **If the portable power station input voltage is in range of the vehicle output can one create a heavy duty cable that skips the intervening inverter/converter technology and connect the 12v battery directly tp the DC solar input on the battery bank or portable power station with the MPPT managing the charging?**

Thanks in advance for any thoughts.

Edit after first comments: It is true that upcoming EV/hybrid vehicles will likely have AC inverters and outlets built into the vehicle. Sometimes accessing the traction battery for tremendous power. Toyota is installing 1,500 inverters at high trim levels.

But there are a ton of EV/hybrid vehicles already on the road. I’m particularly interested in the technical side and avoiding the inverters and converters with a direct cable for charging. Rather than repeat my key question I’ve added “**” around it above. I’ve also made some additional edits.
 
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It’s amazing to me that Will posted this video nearly two years ago and the portable power industry seems not to have responded.

As far as I know every EV/hybrid vehicle with a traditional 12v battery, in addition to the traction battery, can attach an inverter and pull at least 1000 watts continuously (as least 1000 watts is the accepted wisdom for the Prius). As Will illustrates when the vehicle is left turned “on” the traction battery will provide the necessary charge to maintain the charge under load of the 12v battery. Problems only develop if you run out of traction charge on a EV or gas on a hybrid.

Will explains that if you are off grid and have a series of miserable solar days you can use your EV/hybrid to recharge your battery bank.

The portable power manufacturers have successfully made solar charging central. That’s as it should be. They often also ship cigarette lighter chargers which which charge at the 150ish watt limits of that port. It seems no one is selling a charger that connects directly to the 12v car battery like Will does here. As Will illustrates that using the 12v battery directly will charge much more quickly than the cigarette lighter.

These portable power stations already have often significant solar DC input rates. And at least one portable power station has a 12.5 volt minimum input requirement at the bottom of it’s solar input range. Solar charging maximum is 800 watts. The MPPT is built in. (It charges from the wall at 1200 watts.)

I may be missing something very important but given the 12.5+ volts we generally see Will report in the video could a portable power station like this simply be connected to the EV/hybrid 12v directly? No inverter. No additional DC/DC converter. Eliminate these losses. (If your goal is immediate AC power one uses an inverter as Will does here. But if your goal is to charge a 12v DC system it would be ideal to do it directly without a DC/AC/DC series of conversions. I’ll note here that very few portable power stations are 12v systems - most are 24v or 48v. To accomplish what I am describing here would require a voltage booster to be built into those systems. And manufacturer liability may be a big reason this option seems not to be offered.)

However I would think that when manufacturers create portable power stations that can easily be connected to EV/hybrid 12v batteries for high speed charging they will have a hot product on their hands (particularly if it can simultaneously discharge nearly the DC input wattage as AC through the built in inverter). Ideally we avoid fossil fuels altogether but if an EV/hybrid backup makes people more secure about investing in solar then that seems to be a win for the environment.

But time for your advice. After watching Will’s video can it be done as easily as I suggest? If the portable power station input voltage is in range of the vehicle output can one skip the intervening technology and connect the 12v battery directly as a DC “solar” input on the portable power station with the MPPT managing the charging?

Thanks in advance for any thoughts.

Really I do not think it is a good idea.
You have a Buck converter in the EV that makes the 12-14V from the big battery's 2-400V.
You do not know how strong it is, what can it do and how long.
And to replace it if it brakes ... that will cost a lot.
In the Cybertruck there will be 120/240V power outlet. That is a good idea.
Also VtH is a good idea for blackouts but VtG is a terrible ide (to shorten your vehicle battery life even more ... stupid)
 
The new Hyundai Ionic 5 comes with AC power outlets already built into the front and also inside the vehicle. You can plug regular appliances directly into it, or if you like, feed a power inlet to supply your home via a transfer switch. In Australia the car's outlets are our standard 230V AC and can supply up to 3.6kW.

3.6kW is a pretty decent backup power source.

Many EV pickups and SUVs will come with AC outlets as standard. Perfect for trades people and camping.

The downside is of course the EV needs to be at home for it to supply power.

V2H via the dedicated charging system is going to become more common but a few standards need to be sorted out in each region/country. The cost of V2H compatible chargers will also need to drop a lot to be competitive as an option with existing backup power sources.
 
Update: It appears that the makers of the Anderson Powerpole connectors already created cables which are designed for use with Goal Zero equipment. You can see eight different kinds of cables referencing Goal Zero here: https://powerwerx.com/adapter-extension-cables

Goal Zero equipment requires a 14v or greater input to their “solar” DC input system. So it’s likely the system would require a tiny boost in voltage. But if we imagine Goal Zero devices accepted a 12v input could I simply use these cables for directly charging the Goal Zero from the 12v without any additional equipment (the GZ unit has a built in MPPT).

(Again the goal is straight DC wiring and much faster charge than a cigarette lighter.)
 
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Hey I am new at this. I have an EV with 64KW battery. Is there way to us the 12v battery (charged by onboard DC to DC converter) to supply extra power to a battery set up like the one in the video?
Would it be as easy as connecting the car battery in parallel with one of the 12 volt battle born batteries ? Is there a good way to use my car to help keep my battery bank fully charged incase of emergency ?

What happens If you connect the EV battery In parallel to one of the Battle Born Batteries while Battle Born is in 48v series ?
 
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