I would like to focus here on a very specific technical issue which is essential to using your model 3 battery as a power source. I think the key thing question for those of us actually thinking of using the car battery as a power source is whether the dc-dc converter can handle this, or whether it is unwise due to potential impacts on the dc-dc converter. Any thoughts from people who have experience with this or some pertinent technical background would be most helpful.
A bit of background and contextualization: What I would like to do is power a refrigerator and a freezer for up to a week or so as needed (in a power outage). The amount of energy that would consume is modest; about 100 watts each at 50% duty cycle implies 100 watts x 24 hours = 2.4 kWh per day. My model 3 battery stores up to 75 kWh, so 4 days is only about 15%. The draw is also slow, which is benign, so I feel confident that the effect on the battery would be of no significance. I am not concerned about the battery warranty; my battery is excellent so far (more that one year) and I keep it between 30 and 70% most of the time (and never below 10%).
I am, however, pretty concerned about the dc-dc converter. I don't want to trip it or to end up having to replace it. Has anyone done this in a sustained manner? (I know Marc Merlin did a demo with the involved running a microwave, briefly I think. I believe his dc-dc converter tripped at least once which cause me some concern.)
I am pretty sure that with the pick-up truck this would be effortless. I think there are 110 volt outlets, probably 15 amp, probably gfi) in the pick-up truck. So I am wondering about trying to retrofit a model 3 to do that same thing. I think one would have to use the 12 volt posts under the rear seat, connected to an inverter with quite large cables. (5 amps at 120 volts coming out of the inverted implies 50 amps going in at 12 volts.) Additionally, a pre-charge loading circuit would presumably have to be used to control the peak current on the dc side as the capacitors in the inverter charge. While this is benign for the battery (as mentioned above) and it is pretty straightforward, the dc-dc converter is a concern. Can the dc-dc converter handle this, or would it likely lead to dc system problems down the road??
A bit of background and contextualization: What I would like to do is power a refrigerator and a freezer for up to a week or so as needed (in a power outage). The amount of energy that would consume is modest; about 100 watts each at 50% duty cycle implies 100 watts x 24 hours = 2.4 kWh per day. My model 3 battery stores up to 75 kWh, so 4 days is only about 15%. The draw is also slow, which is benign, so I feel confident that the effect on the battery would be of no significance. I am not concerned about the battery warranty; my battery is excellent so far (more that one year) and I keep it between 30 and 70% most of the time (and never below 10%).
I am, however, pretty concerned about the dc-dc converter. I don't want to trip it or to end up having to replace it. Has anyone done this in a sustained manner? (I know Marc Merlin did a demo with the involved running a microwave, briefly I think. I believe his dc-dc converter tripped at least once which cause me some concern.)
I am pretty sure that with the pick-up truck this would be effortless. I think there are 110 volt outlets, probably 15 amp, probably gfi) in the pick-up truck. So I am wondering about trying to retrofit a model 3 to do that same thing. I think one would have to use the 12 volt posts under the rear seat, connected to an inverter with quite large cables. (5 amps at 120 volts coming out of the inverted implies 50 amps going in at 12 volts.) Additionally, a pre-charge loading circuit would presumably have to be used to control the peak current on the dc side as the capacitors in the inverter charge. While this is benign for the battery (as mentioned above) and it is pretty straightforward, the dc-dc converter is a concern. Can the dc-dc converter handle this, or would it likely lead to dc system problems down the road??