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

[shap]

FYI, mine died last Thursday and was towed to the SC yesterday. The 12V replacement batteries arrived today to the SC and I'm expecting to have this (and other things I asked for) done by Friday/Monday. I will take pictures of the batteries once I have the truck back home so people here can tell if there are newer revision or not

Thank you - please do

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[Jakelake]

Thanks for the info on the DCS battery. the PC 680 is only slightly longer so probably will not work. Plus the PC 680 is designed to provide high cranking power to start an ICE. I'm not sure how it would perform if there was a continuous draw on it. I use the PC 680 in my airplanes and they last 7 to 8 years before they need replacement. The DCS battery specifications are not that robust which explains why they don't last very long. And I know from experience these AGM batteries can sometimes fail rapidly even when new. I would not use a LiFeP03 in my Rivian unless Rivian publishes something that says it's OK. These batteries can create all sorts of problems if the BMS is not designed around the battery. They will fail quickly if not properly maintained and they are very expensive. The video for switching from AGM to LFP does not address any of these problems but is quick to note the weight savings. A 12 pound weight difference in a 7000 pound road vehicle is pretty insignificant.

 

[FooF]

I am really surprised that Optima does not provide a battery option for Rivian.
@DCE do you know if Optima has any plans to provide a battery option for Rivian since you worked with them for the SEMA vehicles?

 

[Jakelake]

C&D technologies is not very transparent on the cost of their battery. It's a deep cycle battery which is very different from a starting battery. Anyone know where to buy the DCS-18 battery. My search has not produced anything yet. It took Optima about 2 years to offer a replacement 12 volt battery for my Prius back in 2010 so hopefully they are developing one for the Rivian. It was about a third the price of the replacement battery sold by Toyota.

 

[Yossarian]

Perhaps a naive question, but do the C&D deep cycle batteries used by Rivian differ in any significant way from other AGM DCS batteries?

 

[NY_Rob]

... Also the premature battery failures might have something to do with the supplier they are using for these batteries so for out of warranty trucks might be best to look for alternative suppliers. Just look up the youtube saga going on with DCS batteries and what we are seeing on our trucks.

Unfortunately, most lead-acid batteries are garbage nowadays because, from what I've read they don't use virgin lead like they did back in the day.
Many lead-acid batts including the DCS brand used by Rivian are manufactured using up to 70% recycled lead which leads to shorter life and poorer overall performance. Older guys like myself (I started driving in 1979) remember 12V batteries lasting the lifetime of the vehicle!

 

[Riviot]

Has anyone replaced the 12v themselves? It's got to be a DIY if you link batteries correctly as you're moving them in and out, using a couple jumper cables and changing connections in the right sequence to ensure the system stays loaded.

 

[Tim-in-CA]

So I tested the OBDII 12v battery charger adapter (https://www.amazon.com/dp/B007KJ2RZK) over the weekend for about 24 hours. I used this charger (https://www.amazon.com/YHCHKJ-Maintainer-Fully-Automotive-Desulfator-Motorcycles/dp/B0CQRFN7F9/) since it is 3 amps and comes with the SAE connector. I tested both on our 2nd car first before using on the Rivian.

Results:

• It works. Over a little more than 24 hours, the R1S lost 1 mile. This is way better than normal, where we'd lose 1 mile every 5 hours or so. I didn't make any extra effort to keep the car asleep, and would check the app for mileage whenever I felt curious. The 12v voltage sat around 14.2vs at the beginning and end of the test.
• The results are interesting because we have an early R1S with 2 batteries. I'm guessing that the OBDII connects to the "primary" 12v -- and that the "primary" 12v is the one that needs to be topped off to avoid vampire drain? @NY_Rob -- it'd be interesting to see if you get similar results if you only charged the main 12v, which I believe is closer to the driver side.
• I'm guessing that 3 amps is actually not enough to "top off" the 12v battery, given that it seems to run constantly and there were indications that the 12v battery dipped below 14.2v at some points. I don't have any measuring equipment, so this is just my layman observation.
• The charger draws about 57 watts, although I don't think it's constant. I plugged the charger into my Bluetti to test for a few minutes, and it cycled between 57w and 0, but I'm not sure what the total draw over the period is. The charger was constantly warm (not hot).
• It's an easy way to trickle charge the 12v battery without having to get under the hood. Not sure if I'll bother doing it regularly, since it probably annoys the wife. Could be useful in camping/off grid situations, since have have solar to charge our Bluetti/etc.

Please let me know if I'm doing something wrong and that a housefire is imminent.

EDIT: Forgot to mention: if you are using the adapter + charger I linked to, you have to use a reverse polarity adapter: https://www.amazon.com/dp/B0CGKLPFCP . Otherwise, the charger will throw out error due to reverse polarity protection.

I managed to find a different brand OBD2 to 12V adapter and started testing this afternoon. My preliminary testing so far is VERY promising. My R1S wouldn't stay asleep for more than 30 min without waking up for 15. Now it has slept for 2 hrs. When I plugged in my 3 amp BT, the LED came on to indicate that it was charging, then about 15 min later, it went sold green to indicate charged. Looking forward to see if my VD is decreased, but this is promising. I'll see how the VD looks by morning. For those that garage park this is the easiest method to charge the 12V battery.

The adapter I purchased is https://www.amazon.com/dp/B00Y38WRSI .. it is pretty long and honestly is kinda loose in the OBD2 port. Not sure if the Battery Tender branded one is more snug.

Update : since connecting the OBD2 Battery Tender, my vehicle has slept for about 4 hours and continues to sleep. From the capture below, you can see the constant sleep/wake cycling prior to the tender connection followed by a well deserved long sleep! hopefully it will get more rest and less VD!

 

[NY_Rob]

^ That's great news Tim.... is your Rivian a one or two battery vehicle?

 

[mudito]

I managed to find a different brand OBD2 to 12V adapter and started testing this afternoon. My preliminary testing so far is VERY promising. My R1S wouldn't stay asleep for more than 30 min without waking up for 15. Now it has slept for 2 hrs. When I plugged in my 3 amp BT, the LED came on to indicate that it was charging, then about 15 min later, it went sold green to indicate charged. Looking forward to see if my VD is decreased, but this is promising. I'll see how the VD looks by morning. For those that garage park this is the easiest method to charge the 12V battery.

The adapter I purchased is https://www.amazon.com/dp/B00Y38WRSI .. it is pretty long and honestly is kinda loose in the OBD2 port. Not sure if the Battery Tender branded one is more snug.

Update : since connecting the OBD2 Battery Tender, my vehicle has slept for about 4 hours and continues to sleep. From the capture below, you can see the constant sleep/wake cycling prior to the tender connection followed by a well deserved long sleep! hopefully it will get more rest and less VD!

What do you use to track that?

 

[Tim-in-CA]

^ That's great news Tim.... is your Rivian a one or two battery vehicle?

its a one 12 v battery R1S (July 23 delivery) … still sleeping 5.5 hrs

 

[Tim-in-CA]

What do you use to track that?

I’m using ElectrafI. They have a free trial if you want to try it out

https://www.electrafi.com

 

[NY_Rob]

its a one 12 v battery R1S (July 23 delivery) … still sleeping 5.5 hrs

Thanks, one battery certainly makes things simpler as far as trickle charging is concerned!

 

[Riviot]

I managed to find a different brand OBD2 to 12V adapter and started testing this afternoon. My preliminary testing so far is VERY promising. My R1S wouldn't stay asleep for more than 30 min without waking up for 15. Now it has slept for 2 hrs. When I plugged in my 3 amp BT, the LED came on to indicate that it was charging, then about 15 min later, it went sold green to indicate charged. Looking forward to see if my VD is decreased, but this is promising. I'll see how the VD looks by morning. For those that garage park this is the easiest method to charge the 12V battery.

The adapter I purchased is https://www.amazon.com/dp/B00Y38WRSI .. it is pretty long and honestly is kinda loose in the OBD2 port. Not sure if the Battery Tender branded one is more snug.

Update : since connecting the OBD2 Battery Tender, my vehicle has slept for about 4 hours and continues to sleep. From the capture below, you can see the constant sleep/wake cycling prior to the tender connection followed by a well deserved long sleep! hopefully it will get more rest and less VD!

How are you running the line from trickle charger to OBD2? If this were permanent, would you pass it through the firewall and create an external connector?

 

[Tim-in-CA]

How are you running the line from trickle charger to OBD2? If this were permanent, would you pass it through the firewall and create an external connector?

I’m passing it through the passenger window. My car is garaged.

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