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I chose to post separately from my original thread as it's more hybrid specific. No need to make the gas only owners jealous :D

This inverter mod is one which I was fascinated with when I read that other people use their Prii as a "plug out kit" during power outages. Essentially the vehicle acts as an efficient generator with 55L fuel tank. The 12v battery powers the inverter and the traction battery powers the 12v battery. The hybrid components enable the engine to power on and off charging and generating electricity to suit the different loads required.

I started with a quality Thor 2000 watt pure sinewave power inverter. I believe the Toyota inverter/converter system is capable of delivering up to 800-1000 watts of continuous power but that was several generations ago. I'm not too sure what the maximum power is for this current THS generation but it's probably safe to assume that sticking with anything under 1000 watts would be fine. My primary purpose is to be able to power my fridges, freezer, router, laptop, gas furnace and gas water heater in the event of an extended power outage. 1000 watts would be quite tight but if everything takes turns and the load is monitored through a Kill-a-Watt it should be fine. 2000 watts gives enough surge capability without the overloading the inverter. There are many complaints of various inverters not meeting the advertised specs thus stick with the higher priced units for higher quality parts. You get what you pay for. I tested my setup using a table saw with a 3400 watt in-rush current without any issues. To operate, it's as simply as hooking everything up, starting the car as normal and leaving the vehicle unattended like any other generator. The hybrid system will turn on the engine whenever the 12v battery drops in voltage.

Suffice it to say, don't do this in an enclosed garage where carbon monoxide could build up. Monitor your gas levels so you don't run it bone dry. Have a second key and lock the doors so your vehicle doesn't get stolen. Watch the wattage draw so you don't kill your 12v battery or worse yet, destroy the hybrid components drawing too much power. Use heavy duty extension cords with a low AWG for longer distances.

For the parts, I bought 6' each of red and black 1/0 cable, 200A ANL fuse with holder, 175A anderson connectors and appropriate lug nuts. With the stiffness of the cable and how unwieldy it was, it took a lot of patience to measure and figure out how best to route the cables. I like how there's a removable false floor with a nook to the spare wheel well that the cable can pass through. This way I don't have to remove the main floor panel when in use or cut/drill any unsightly holes. One thing to note is that because this is a hybrid, the 12v AGM battery is in the trunk. Non-hybrid models that use standard lead acid batteries aren't suitable for deep discharging. The engine would also have to run continuously negating any efficiencies.
 

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This is all a very interesting project that I'm sure many other hybrid owners have been doing for years. As an EE I could do it on my 2018 Accord Hybrid and measure all the amps, volts and watts. But I won't because I don't see the point of taking ANY chances of damaging my $25,000 car when a 2000W inverter generator can do the same thing.

A top-of-the line Honda EU2000i pure sine wave generator that will run even the most sensitive electronics is $1,000. It runs quiet and with a 5 gallon boat gas tank added will easily run for 24 hours, maybe days. Use the Harbor Freight equivalent and you'd do the same for half that cost.

And if I did run backup power off my Accord that ties me home to keep my frig, lights etc. running. YMMV, but the car-tied inverter just doesn't compute for me.
 

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I chose to post separately from my original thread as it's more hybrid specific. No need to make the gas only owners jealous :D

This inverter mod is one which I was fascinated with when I read that other people use their Prii as a "plug out kit" during power outages. Essentially the vehicle acts as an efficient generator with 55L fuel tank. The 12v battery powers the inverter and the traction battery powers the 12v battery. The hybrid components enable the engine to power on and off charging and generating electricity to suit the different loads required.

I started with a quality Thor 2000 watt pure sinewave power inverter. I believe the Toyota inverter/converter system is capable of delivering up to 800-1000 watts of continuous power but that was several generations ago. I'm not too sure what the maximum power is for this current THS generation but it's probably safe to assume that sticking with anything under 1000 watts would be fine. My primary purpose is to be able to power my fridges, freezer, router, laptop, gas furnace and gas water heater in the event of an extended power outage. 1000 watts would be quite tight but if everything takes turns and the load is monitored through a Kill-a-Watt it should be fine. 2000 watts gives enough surge capability without the overloading the inverter. There are many complaints of various inverters not meeting the advertised specs thus stick with the higher priced units for higher quality parts. You get what you pay for. I tested my setup using a table saw with a 3400 watt in-rush current without any issues. To operate, it's as simply as hooking everything up, starting the car as normal and leaving the vehicle unattended like any other generator. The hybrid system will turn on the engine whenever the 12v battery drops in voltage.

Suffice it to say, don't do this in an enclosed garage where carbon monoxide could build up. Monitor your gas levels so you don't run it bone dry. Have a second key and lock the doors so your vehicle doesn't get stolen. Watch the wattage draw so you don't kill your 12v battery or worse yet, destroy the hybrid components drawing too much power. Use heavy duty extension cords with a low AWG for longer distances.

For the parts, I bought 6' each of red and black 1/0 cable, 200A ANL fuse with holder, 175A anderson connectors and appropriate lug nuts. With the stiffness of the cable and how unwieldy it was, it took a lot of patience to measure and figure out how best to route the cables. I like how there's a removable false floor with a nook to the spare wheel well that the cable can pass through. This way I don't have to remove the main floor panel when in use or cut/drill any unsightly holes. One thing to note is that because this is a hybrid, the 12v AGM battery is in the trunk. Non-hybrid models that use standard lead acid batteries aren't suitable for deep discharging. The engine would also have to run continuously negating any efficiencies.

Sent you a personal message about your install. Would love to gather more info, ask you some more detailed questions.

Thanks,
 

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This is all a very interesting project that I'm sure many other hybrid owners have been doing for years. As an EE I could do it on my 2018 Accord Hybrid and measure all the amps, volts and watts. But I won't because I don't see the point of taking ANY chances of damaging my $25,000 car when a 2000W inverter generator can do the same thing.

A top-of-the line Honda EU2000i pure sine wave generator that will run even the most sensitive electronics is $1,000. It runs quiet and with a 5 gallon boat gas tank added will easily run for 24 hours, maybe days. Use the Harbor Freight equivalent and you'd do the same for half that cost.

And if I did run backup power off my Accord that ties me home to keep my frig, lights etc. running. YMMV, but the car-tied inverter just doesn't compute for me.
Turning a vehicle that (potentially) costs $40k into a 'stop-gap' A/C Generator is pure evil genius.

Walking past the graveyard at LIGHTSPEED when you could spend < $20k ($15k ? ) on a complete whole house propane gen/set with transfer switch.

It's right up there with 'hold my beer' or 'hey, watch this'. But this is the beautiful thing about humanity and how it takes all kinds to make the world go 'round. :D
 

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The 2021 Senna will have an option for a 1500 watt inverter. It will be interesting to see if Toyota uses the 12 volt system or the 3 phase high voltage system to power the inverter.

Toyota in the past tested a system to power homes from hybrids after a power outage,

For my, I have a 1000 watt true sine wave inverter to connect to my 12 volt battery as a back up to my 3K Yamaha inverter generator. Living in hurricane county it is nice to have a plan B. If the inverter/hybrid is needed, I would cycle essentials needed keeping the load under 800 watts.
 

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I've read a few posts of people doing this on Prii and other toyota hybrids, I have yet to see anyone complain of anything going wrong. I get the impression that staying below 1000W is a safe threshold that most have tried. I haven't heard any success stories of anyone getting closer to 1500W (Which would be the standard max you would get out of most appliances). If anyone has tried 1500W I'd love to hear how it's working for you.

This generator setup is pretty genius. If power outages are a regular occurrence in your area, you would be better suited for a dedicated option, but if power outages aren't a regular thing and you like the idea of being prepared to plug in essentials, or you want to have extra appliances with you on the road while camping, this is far cheaper, lighter, effective, and less maintenance than a dedicated gas generator.
 

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I've read a few posts of people doing this on Prii and other toyota hybrids, I have yet to see anyone complain of anything going wrong. I get the impression that staying below 1000W is a safe threshold that most have tried. I haven't heard any success stories of anyone getting closer to 1500W (Which would be the standard max you would get out of most appliances). If anyone has tried 1500W I'd love to hear how it's working for you.
Volt and Bolt EV Inverter Kits Availability Coming to an End...

Have successfully used 2500W pure sine inverter in my Gen1 volt as described in the link above but haven't tried to max out the full 2500W since the Gen1 APM capacity is @2kW...
 

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Volt and Bolt EV Inverter Kits Availability Coming to an End...

Have successfully used 2500W pure sine inverter in my Gen1 volt as described in the link above but haven't tried to max out the full 2500W since the Gen1 APM capacity is @2kW...
Unfortunately the specs on the DC to DC converter for the rav4 (and toyota's) is harder to come by than for the chevy volt! 1000W should be sufficient for most I suppose, probably better to play it safe. That can power a fridge, internet modem, TV, fan, and some lights.
 

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I've read a few posts of people doing this on Prii and other toyota hybrids, I have yet to see anyone complain of anything going wrong. I get the impression that staying below 1000W is a safe threshold that most have tried. I haven't heard any success stories of anyone getting closer to 1500W (Which would be the standard max you would get out of most appliances). If anyone has tried 1500W I'd love to hear how it's working for you.

This generator setup is pretty genius. If power outages are a regular occurrence in your area, you would be better suited for a dedicated option, but if power outages aren't a regular thing and you like the idea of being prepared to plug in essentials, or you want to have extra appliances with you on the road while camping, this is far cheaper, lighter, effective, and less maintenance than a dedicated gas generator.
Yes, I think the key unknown is has Toyota upped the 12 volt charging circuit on their larger hybrid systems from the Prius's on the 2.5 hybrid? I believe all of their hybrids use the same 12 volt battery but that may not be an indicator of the charging circuit capacity. I guess when someone explores the new 1500 watt inverter in the upcoming Senna we will have more information. I assume do to costs, Toyota will not be stepping down the 3 phase HV battery to a 120 volt power inverter but who knows.

For now, I have a 1000 watt, 2000 watt peak pure sine wave inverter. It would be nice to have the extra 500 watts for appliance surges.

I think your synopsis of using the car as a generator is spot on. Most generator failures are due to stale gas and not running the generator under a load on a regular basis. Some generators loose their magnetic field charge from not being run with a load.

By using a hybrid, one always has fresh gas, a safe way to store the gas, and a "generator" that is maintained.

As I stated about, my hybrids generating electricity are my plan B as I have an inverter generator. That being said if Toyota offered a HV disconnect to connect to my main panel I would consider using it.
 

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You can use a capacitor like this for initial surge when device turned on, it connects between invertor and battery, also can daisy chain another battery between (must have same specs) as a buffer, there is a kit that allows liFePo4 battery to connect, I have 180Ah Li-ion connected to 3000 watt inverter, but extra cargo, there used to a company that had a kit to hook directly to NiMh battery and youtube vids, I recharge thru solar or 12v plug https://www.amazon.com/PLCAPE50-Farad-Digital-Power-Capacitor/dp/B001Q5SMEE/ref=sr_1_7?dchild=1&keywords=capacitor+audio&qid=1590243296&sr=8-7 HERE to connect starter battery to Lithium battery scroll down to Li ion series PDF and open for diagram for battery combiner Cyrix Battery Combiners - Victron Energy
 

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I really like the idea of using a similar system (maybe with an additional battery connected with VSR/isolator) for connecting auxiliary devices (Computer, Fridge, etc.) but I have some question that keeps bugging me.

12V Battery needs to be charged with limited current(0.1C - 0.2C) for its safety that's why I was thinking that current delivered to the positive terminal of the 12V battery is limited but I saw your post (and many similar ones) that connect loads to the positive terminal of the battery and uses the output of the DC-DC converter. How is this possible? Does the battery have an internal charging circuit that limits the charging current?

I would be very happy if there is someone that can help me clarifying this confusion of mine :rolleyes:
Thanks in advance
 

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I suspect the DC-DC converter has a constant voltage output just like the alternator in a conventional gas-only car.
Since the small 12V battery in a hybrid never has to deliver high current such as starting the engine its voltage doesn't drop enough to draw high current from the DC-DC converter. Any current above normal such as to an inverter would be delivered to the added load not the baby 12V battery.
 

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The negative terminal of the battery is connected to a sensor that regulates the charging of the 12 volt battery. Here is a video that explains the charging system,
I really like the idea of using a similar system (maybe with an additional battery connected with VSR/isolator) for connecting auxiliary devices (Computer, Fridge, etc.) but I have some question that keeps bugging me.

12V Battery needs to be charged with limited current(0.1C - 0.2C) for its safety that's why I was thinking that current delivered to the positive terminal of the 12V battery is limited but I saw your post (and many similar ones) that connect loads to the positive terminal of the battery and uses the output of the DC-DC converter. How is this possible? Does the battery have an internal charging circuit that limits the charging current?

I would be very happy if there is someone that can help me clarifying this confusion of mine :rolleyes:
Thanks in advance
 

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I suspect the DC-DC converter has a constant voltage output just like the alternator in a conventional gas-only car.
Since the small 12V battery in a hybrid never has to deliver high current such as starting the engine its voltage doesn't drop enough to draw high current from the DC-DC converter. Any current above normal such as to an inverter would be delivered to the added load not the baby 12V battery.
When I change mode of the car to the ready mode, I did observe 14.2V at the positive terminal of the battery (Previously it was around 12.2-12.6 V). Meaning that it could draw quite some current.

The negative terminal of the battery is connected to a sensor that regulates the charging of the 12 V battery. Here is a video that explains the charging system,
I did see this video and it was quite helpful. But what I couldn't understand is how that sensor regulates the charging system since used power is coming from the same terminal(also the same cable) used for connecting high power devices in some examples(as in this thread). I guess changing the output voltage is the only thing DC-DC converter can do to limit the charging current using the sensor readings but I couldn't observe it (the car was stationary but I don't think it changes much).
 

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14.1 is a typical 12V battery charging voltage, you don't really need to regulate current. I don't have a hybrid myself yet, but on my standard car that I still drive to this day with an alternator, I've used a cigarette lighter voltmeter to see what the alternator system does. It typically runs at 14.1V for like 70% of the time, only whenever my car decelerates will it go higher for a few seconds, or if it thinks the battery is really charged up, it will drop to 12.7V sometimes whenever I'm accelerating.

For you, why do you want a second battery? You should be fine connecting to just the one. Remember, you're not really running off the battery at all (maybe for little spikes in current), it's the DC to DC converter you're running off of.
 

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14.1 is a typical 12V battery charging voltage, you don't really need to regulate current. I don't have a hybrid myself yet, but on my standard car that I still drive to this day with an alternator, I've used a cigarette lighter voltmeter to see what the alternator system does. It typically runs at 14.1V for like 70% of the time, only whenever my car decelerates will it go higher for a few seconds, or if it thinks the battery is really charged up, it will drop to 12.7V sometimes whenever I'm accelerating.
You are right about charging voltage, I have no saying in that. What I don't understand is how charging current is limited when the DC-DC converter does supply around 1000W of power from that same line. (Internal resistance of the battery is almost negligible at 0.1-0.2C)

For you, why do you want a second battery? You should be fine connecting to just the one. Remember, you're not really running off the battery at all (maybe for little spikes in current), it's the DC to DC converter you're running off of.
I just want to able to run some tools even when the car is not in ready mode and don't want to risk of draining the auxiliary battery since it would still result in me being not able to run the car :D
 

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You are right about charging voltage, I have no saying in that. What I don't understand is how charging current is limited when the DC-DC converter does supply around 1000W of power from that same line. (Internal resistance of the battery is almost negligible at 0.1-0.2C)
The explanation would require a primer on electricity namely the difference between voltage, current and power.

I just want to able to run some tools even when the car is not in ready mode and don't want to risk of draining the auxiliary battery since it would still result in me being not able to run the car :D
This is a good idea especially if you include a battery idolator as used on RVs.
 

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You are right about charging voltage, I have no saying in that. What I don't understand is how charging current is limited when the DC-DC converter does supply around 1000W of power from that same line. (Internal resistance of the battery is almost negligible at 0.1-0.2C)


I just want to able to run some tools even when the car is not in ready mode and don't want to risk of draining the auxiliary battery since it would still result in me being not able to run the car :D
I think you're misunderstanding some of the fundamentals. Charging current is limited by the voltage of the system. As the battery fills up, it can no longer take on additional charge at 14.1V. Here's a good website that explains how battery charging works, this website can teach you almost everything you could ever learn about batteries: Charging Information For Lead Acid Batteries – Battery University

The AGM batteries in the hybrid system aren't designed to cycle quickly like a typical starter battery. You really should only be running the inverter on the system when the car is in ready mode. If you want to run some tools temporarily without the car powered on, your best bet might be to look at some off-the-shelf Lithium battery solutions. Lead Acid is heavy and messy, and the hybrid isn't design to charge two LA batteries at the same time.

Hope this helps!
 
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