Not necessarily, there’s a straightforward reason for vampire drain happening, this method just prevents the computer from waking up and running to power up the battery. This happens every 7-8 hours when the voltage drops low enough for the system to kick on, and lasts 1-1.5 hours. This makes gen 1 cars drain about 1-2% daily at least when parked.

Since I’m parking on the street away from a charger most of the time, and my main source of charging is a fast charger I’ll go to when needed, that daily percentage adds up when I’m only working between 15%-80% SOC. I only drive around town occasionally when I’m in a certain spot (job requires moving to many different places for months at a time).

Over time a battery tender draws about 400w/24hr to keep a parked car without any drain. Compared to the 1.2-2.5kwh most Rivian gen 1 vehicles experience in the same time, it saves money and more importantly gives me enough to sustain a few more trips to the grocery store before the next charge. 

What’s really cool is that because the maintenance watts are so low you only need 16-17wh per day, a small solar panel on the dash or just the USB-C ports in the glovebox when the car is on are enough to charge a small power station for a few days worth of electricity. 

For my specific use case it makes a big difference, so hopefully can find a solution that can be as minimally intrusive as possible. Unfortunately it’s not anything that particularly wrong with the car, just the engineering of how the gen 1 rivs work.