Forum Discussion

Gjac's avatar
Gjac
Explorer III
Aug 29, 2022

Will this work

Last year my genset stopped working in my MH. I rarely used it anyway except to exercise it. However, I did use it whenever we had a power outage due to a storm to keep my refrigerators cold. I have gas hot water and a wood burning stove for heat if outage happens in the winter months so the only thing, I need power for is the refrigerators. I was thinking about buying a small generator then after reading several threads about Jackery's or making your own Li battery backup systems. It started me thinking about what I already have at home to make something that I would only use once a year or less. I have a 2019 Toyota Rav4 Hybrid car, a MH with 2 6v GC batteries with a 1000-watt MSW inverter already in place. The hybrid has a large HV traction battery and a small accessary battery 55 AH's. The large battery starts the ice engine, which then charges the traction battery from 20% SOC to 80% SOC then shuts off. So, my thought was to just back up my hybrid to MH and jump the hybrid 12v accessory battery to the house batteries, plug an extension cord into the inverter and connect it to my refer. The car has an 8.8KWH generator and when the HV (201V) traction battery gets low the engine will start to recharge the HV battery and supply voltage to the 12v accessory battery. The devil is usually in the details, so am I missing anything?
  • Gjac's avatar
    Gjac
    Explorer III
    valhalla360 wrote:
    I know Fords F150, they set it up to do this and actually have an upgrade that puts some 120v outlets in the bed.

    The question is does your toyota have a 120v outlet or if not, does the 12v come from the big battery bank. Most propulsion battery banks are not 12v, so it wouldn't surprise me if the big battery bank is at a higher voltage and the 12v outlet is pulling off the small battery.
    I do not have a 120v outlet only a 12v outlet. The traction/propulsion battery is a little over 200 v which in turn supplies voltage to the 12 v battery which in turn is connected to the 12v outlet.
  • I know Fords F150, they set it up to do this and actually have an upgrade that puts some 120v outlets in the bed.

    The question is does your toyota have a 120v outlet or if not, does the 12v come from the big battery bank. Most propulsion battery banks are not 12v, so it wouldn't surprise me if the big battery bank is at a higher voltage and the 12v outlet is pulling off the small battery.
  • Gjac's avatar
    Gjac
    Explorer III
    wanderingaimlessly wrote:
    Are you certain the hybrids HV battery powers the 12 accessory outlet?
    It would seem simpler for the manufacturer to power that from the 55 AH 12 volt starting battery.
    The way it works is the engine turns the electric motor which charges the HV battery and the HV battery then charges/maintains the 12V acc battery. The 12V acc battery is not a starting battery the HV battery starts the engine.
  • Gjac wrote:
    rgatijnet1 wrote:
    My Ford hybrid has a 120 volt outlet that I can use when the motor is idling. This is large enough to power most refrigerators. Are you sure that your Toyota does not have a 120 volt outlet that you can use. Much easier than rigging up anything else.
    Mine only has a 12v plug in the rear. I could hard wire an inverter directly to the battery there but for once a year think it would be easier to just use jumper cables to the MH which already has a 230 AH battery backup system and an inverter. Do you have the Ford Escape?


    I have a Ford Fusion and in the back of the center console there is a 12 volt power feed, USB power outlet, and a 120 volt outlet. I think mine is only rated at 200 watts which is enough for most refrigerators.
  • Is there a fuse on the charging path for hybrid to 12 volt battery? If so replace it with a circuit breaker? What size is the wire.

    Have you tried running the fridge on the 1000 watt inverter? It might not have enough "head room" for the surge.

    Considering how cheap a 3500 Harbor Freight generator sells for, I'd probably go that route.
  • Gjac's avatar
    Gjac
    Explorer III
    rgatijnet1 wrote:
    My Ford hybrid has a 120 volt outlet that I can use when the motor is idling. This is large enough to power most refrigerators. Are you sure that your Toyota does not have a 120 volt outlet that you can use. Much easier than rigging up anything else.
    Mine only has a 12v plug in the rear. I could hard wire an inverter directly to the battery there but for once a year think it would be easier to just use jumper cables to the MH which already has a 230 AH battery backup system and an inverter. Do you have the Ford Escape?
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Yes many use Hybrid cars or EV's as emergency power already.. Some companies even advertise that use.. The only dangers I see in doing it is not being able to get where you need to go due to Low/Dead battery (Do not know how good the safety systems are on the batteries).

    And of course you feed power to your house via a proper GENERATOR TRANSFER system not by backfeeding an outlet.. for therein (Backfeeding) Well they do not call the necessary cable a "Suicide cord" for nothing.
  • My Ford hybrid has a 120 volt outlet that I can use when the motor is idling. This is large enough to power most refrigerators. Are you sure that your Toyota does not have a 120 volt outlet that you can use. Much easier than rigging up anything else.
  • Are you certain the hybrids HV battery powers the 12 accessory outlet?
    It would seem simpler for the manufacturer to power that from the 55 AH 12 volt starting battery.
  • Just about any idea will make more sense than a Jackery.