Gen 1 Vampire Drain (Possibly) Solved (or Hacked)

[HaveBlue]

I don't think so. As I understand it the claim is that the HV battery is used to maintain the 12V battery, so if you leave the vehicle unattended the HV battery slowly drains as it maintains the 12V battery.

OP's idea is to offset that by directly maintaining the 12V battery/ies(?) from wall power, so the HV battery never needs to give any charge to the 12V.

The theory as to why this might be desirable is summarized by @Zoidz:



No one has tested the power drawn by a battery maintainer vs. that drawn by the EVSE while maintaining the HV battery charge, so no one knows for sure if that theory is true.

Well considering the car loses 1-2kwh per day to maintain an 18ah (200wh) battery, the math is pretty evident by about 10x.

Rivian's advice of leaving the car plugged in when leaving for an extended trip makes the drain worse as the car is awake even more. If you look at the session data after charging you'll see that the car burned a few kwh running accessories.

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[Moller_CO]

I'm jumping on, as I had an experience today that was unsettling. This past week I have been using the R1S extensively to shuttle family members to/fro our family reunion events. Following the reunion, I charged the car and let is sit... just didn't need to go anywhere. I had an 80% charge at 9 am on a Monday. When I piled in the car on Tuesday at noon (27 hours later) the car only had 46% charge.
The car had self-locked, leading me to believe that it was 'asleep'. Any thoughts on what happened? I've owned the car since early June, and this is the 2nd time this has occurred. I'm sure Rivian could be helpful here, but they don't seem to be answering CS calls in Denver.

Appreciate any thoughts that come to mind.

 

[Tim-in-CA]

I'm jumping on, as I had an experience today that was unsettling. This past week I have been using the R1S extensively to shuttle family members to/fro our family reunion events. Following the reunion, I charged the car and let is sit... just didn't need to go anywhere. I had an 80% charge at 9 am on a Monday. When I piled in the car on Tuesday at noon (27 hours later) the car only had 46% charge.
The car had self-locked, leading me to believe that it was 'asleep'. Any thoughts on what happened? I've owned the car since early June, and this is the 2nd time this has occurred. I'm sure Rivian could be helpful here, but they don't seem to be answering CS calls in Denver.

Appreciate any thoughts that come to mind.

Check to see if any seat belts were left buckled. If not, try a reboot of the vehicle (left most steering wheel button and hazard light button pressed simultaneously)

 

[Moller_CO]

Check to see if any seat belts were left buckled. If not, try a reboot of the vehicle (left most steering wheel button and hazard light button pressed simultaneously)

Ahhhh ...that's odd. The passenger side seat belt was buckled, and obviously had been the entire time it sat idle. What's the story with that?...

 

[Tim-in-CA]

Ahhhh ...that's odd. The passenger side seat belt was buckled, and obviously had been the entire time it sat idle. What's the story with that?...

Well one of your passengers must have left it that way. Vehicle stays awake when a belt is buckled. Would be good if app sent an alert

 

[josh0]

Well one of your passengers must have left it that way. Vehicle stays awake when a belt is buckled. Would be good if app sent an alert

Interesting. I don’t think this is true for all the belts. We leave the center rear belt buckled all the time, as it has a carabiner on it that hooks to our dog’s harness, and I’ve never seen this sort of extreme drain.

 

[evoluzione]

Let me throw out another consideration. I do not have the ability to charge at home and just had to replace the 12v batteries on my LE R1T. I was quoted $822 for the replacement. Based on this, it might be worthwhile to find something that would help keep the 12v batteries in top shape. I'm thinking of mounting a solar panel on the roof racks, which would serve two purposes - keep the 12v batteries charged and provide a external shade for the glass roof.

 

[emoore]

Interesting. I don’t think this is true for all the belts. We leave the center rear belt buckled all the time, as it has a carabiner on it that hooks to our dog’s harness, and I’ve never seen this sort of extreme drain.

Only true of the front seat belts. Don't think the back seat belts matter.

 

[CarlM408]

Only true of the front seat belts. Don't think the back seat belts matter.

Just testing this right now actually, buckled one of the back seats this morning, parked at the office, truck has been happily sleeping the past 1.5 hours no problem.

 

[Yossarian]

Let me throw out another consideration. I do not have the ability to charge at home and just had to replace the 12v batteries on my LE R1T. I was quoted $822 for the replacement. Based on this, it might be worthwhile to find something that would help keep the 12v batteries in top shape. I'm thinking of mounting a solar panel on the roof racks, which would serve two purposes - keep the 12v batteries charged and provide a external shade for the glass roof.

Maybe a bit like this?

Hmmm. How about a 12v charging system consisting of PV panels, controller and storage battery that connects through the 7 pin tow harness receptacle?

I'd envision a few flexible PV panels that could be spread out on the roof and anchored at the cross-bar accessory ports. The controller and storage battery could go in the frunk and connect to the panels through a flat wire harness; this would allow frunk to close easily and not damage the wire. Another flat harness could be used to connect to the the tow harness receptacle at the rear. The idea behind ading a small storage battery is to help charging continue through the non-daylight hours.

No EE background so not sure how viable any of this is. It wouldn't be needed at all if it's possible to safely (i. e., not brick the vehicle) disconnect the 12v system via a simple switch.

 

[jplblue]

Let me throw out another consideration. I do not have the ability to charge at home and just had to replace the 12v batteries on my LE R1T. I was quoted $822 for the replacement. Based on this, it might be worthwhile to find something that would help keep the 12v batteries in top shape. I'm thinking of mounting a solar panel on the roof racks, which would serve two purposes - keep the 12v batteries charged and provide a external shade for the glass roof.

Are there any aftermarket lead acid batteries that will fit the Rivian? I heard they were basically power sports batteries, but can't find find any with the same dimensions 7.1''Lx3''Wx7.4''H. $822 for new batteries is a little over-the-top.

 

[CO-rayman]

Are there any aftermarket lead acid batteries that will fit the Rivian? I heard they were basically power sports batteries, but can't find find any with the same dimensions 7.1''Lx3''Wx7.4''H. $822 for new batteries is a little over-the-top.

Others have used an upgraded Lithium battery but I have no experience with that. Here is a link to the battery but I am sure you can search the forum for more info.

https://www.ohmmu.com/product-page/12v-lithium-battery-for-r1t-r1s

 

[racekarl]

Well considering the car loses 1-2kwh per day to maintain an 18ah (200wh) battery, the math is pretty evident by about 10x.

Only IF this experiment is successful and reproducible. What we have so far is an anecdote, not data.

 

[HaveBlue]

That's true someone might have a battery tender that draws a lot of power or there is such a high vampire drain that the battery constantly needs to be charged. After all a desktop computer has a 500w power supply. Who knows what kind of crazy engineering waste rivian handed us.and where the major inefficiencies are. Could be in several areas.

 

[CarlM408]

That's true someone might have a battery tender that draws a lot of power or there is such a high vampire drain that the battery constantly needs to be charged. After all a desktop computer has a 500w power supply. Who knows what kind of crazy engineering waste rivian handed us.and where the major inefficiencies are. Could be in several areas.

By my math fwiw, it's basically 400w of power when all the computers are humming (~1 MPH drain, or 6.5%/day (R1T PDM Max), you can force this by turning on the power outlets)

OTOH, a normal quiet day is more like 1%, which translates to ~60w of draw. It's not really continuous of course as things cycle to, we presume, charge up the 12v system, and whatever other routine maintenance tasks there may be.

Will that Ohmmu battery, which has ~3x the capacity, allow the 12v charger to cycle less often, allowing that 60w average to be driven down lower? I had a chat with their support folks, they said maybe but are doubtful it will be measurable, but what the heck I ordered one and will find out.

Also I've got the parts I think for the battery tender idea, very much TBD there too, I'm doubting the trailer hitch power is active 24/7 but maybe I'm wrong...if it isn't I'll need to dig into the front, but I need to do that soon anyway to upgrade the horn

With either of the above options, the altered sleep cycle should show up clear as day in Electrafi, so ?

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