Sponsored

trickle charge 12 volt

Tim-in-CA

Well-Known Member
Joined
Sep 30, 2021
Threads
46
Messages
1,793
Reaction score
3,429
Location
So Cal
Vehicles
Gen 1 R1S, Lucid Air, T-Bird
Just curious, why does this method only work great if the vehicle is garaged?
I keep a window open to run the Battery Tender cable so I don't have worry about weather. Otherwise, you would have to take actions to mitigate. Others provided their solutions in the aforementioned thread.
Sponsored

 

tjrivian

Well-Known Member
Joined
Oct 4, 2024
Threads
9
Messages
211
Reaction score
184
Location
san diego
Vehicles
Tesla Model X
I keep a window open to run the Battery Tender cable so I don't have worry about weather. Otherwise, you would have to take actions to mitigate. Others provided their solutions in the aforementioned thread.
Ahh, I did not realize that the battery tender had to be PLUGGED INTO THE WALL. I thought the battery tender had a battery itself(that you'd periodically recharge by bringing it into your house to recharge), and was just dumping a bit of charge from it's battery into the 12V car battery. Please forgive my ignorance.
 

Tim-in-CA

Well-Known Member
Joined
Sep 30, 2021
Threads
46
Messages
1,793
Reaction score
3,429
Location
So Cal
Vehicles
Gen 1 R1S, Lucid Air, T-Bird
Ahh, I did not realize that the battery tender had to be PLUGGED INTO THE WALL. I thought the battery tender had a battery itself(that you'd periodically recharge by bringing it into your house to recharge), and was just dumping a bit of charge from it's battery into the 12V car battery. Please forgive my ignorance.
They do make a version with a solar panel, but I have no experience with that type
 

Herb

Well-Known Member
First Name
Herbert
Joined
Oct 17, 2023
Threads
0
Messages
163
Reaction score
134
Location
Ohio
Vehicles
911, John Deere, R1T max DMP
I believe another option is to wire a trickle charger to 12V "cigarette lighter" plug and use the socket in the gear tunnel. You will have to set the delay timer for your outlets (110V and 12V run off the same timer) or they shut off soon after exiting the vehicle. Max delay time is 3 days, so it doesn't work for every case. The outlet is protected with a 20A fuse (don't ask how I know).
 

gultin

Well-Known Member
First Name
S
Joined
Sep 30, 2021
Threads
13
Messages
230
Reaction score
354
Location
CO
Vehicles
R1T
I use an OBD 2 port adapter to my Battery Tender for my Gen 1 (single 12V battery) R1S. Prior to connection, my R1S would have a VD of 1 to 2% (sometimes more) per night and would wake up every few hours. Now, it sleeps for 12-24 hrs or more and the VD is around 0.2 to 0.4%. This method works great if the vehicle is garaged.

https://www.amazon.com/Battery-Tender-081-0154-DL-Connector-Maintainers/dp/B007KJ2RZK

There is a very LENGTHY thread (29 pages!) discussing all the possible solutions to resolve VD, keeping the 12V battery topped up (even when new) seems to be the solution for Gen 1 vehicles.

https://www.rivianforums.com/forum/...ly-solved-or-hacked.31506/page-23#post-621430
@Tim-in-CA which battery tender product do you use plugged into the wall? Curious what it's specs are. Also, do you know if this approach would work for Gen1 with dual 12V batteries?
 

Sponsored

Tim-in-CA

Well-Known Member
Joined
Sep 30, 2021
Threads
46
Messages
1,793
Reaction score
3,429
Location
So Cal
Vehicles
Gen 1 R1S, Lucid Air, T-Bird

gultin

Well-Known Member
First Name
S
Joined
Sep 30, 2021
Threads
13
Messages
230
Reaction score
354
Location
CO
Vehicles
R1T
Thanks @Tim-in-CA! I had a chance to try both of these Battery Tender products (3 Amp tender and OBD adapter) and it appears to work with my Gen 1 with dual 12V. Over last night I only lost 1 mile over a 12-hour period, whereas otherwise it is typically a 2-3 mile loss overnight at these temperatures. The best part was that it just took under a minute to setup and similarly quick to remove. I'll monitor this over a few more nights.











Out of curiosity, I also tried a 30 watt solar panel with MPPT behind my windshield, which also seems to work through the OBD adapter and showed a full charge within 10 minutes. This was also super easy to setup, and the panel stays securely tucked behind the A pillar, without the need for any additional securing. This took under a minute to setup and take down.

Here's the solar panel in case anyone else is interested.
https://a.co/d/f2J3cSJ

Assuming this works well, I plan to use the 3 Amp tender + OBD at home, and the solar+OBD on camping trips.

Rivian R1T R1S trickle charge 12 volt IMG_20250322_143929


Rivian R1T R1S trickle charge 12 volt IMG_20250322_123615~2
 
Last edited:

IGR

Well-Known Member
Joined
Jul 7, 2023
Threads
8
Messages
360
Reaction score
506
Location
SoCal
Vehicles
Rivian R1S
Occupation
I make things
Clubs
 
This looks like a great idea with the solar panels, unfortunately won’t be as effective for those who have tints.
If let’s say tints block 50% light would that still be enough juice to maintain 12v battery?
 

gultin

Well-Known Member
First Name
S
Joined
Sep 30, 2021
Threads
13
Messages
230
Reaction score
354
Location
CO
Vehicles
R1T
This looks like a great idea with the solar panels, unfortunately won’t be as effective for those who have tints.
If let’s say tints block 50% light would that still be enough juice to maintain 12v battery?
My windshield is actually at a 70% tint, and it charged up the 12V fine from inside the windshield, on a bright/sunny day. So I'm hopeful.
 

IGR

Well-Known Member
Joined
Jul 7, 2023
Threads
8
Messages
360
Reaction score
506
Location
SoCal
Vehicles
Rivian R1S
Occupation
I make things
Clubs
 
My windshield is actually at a 70% tint, and it charged up the 12V fine from inside the windshield, on a bright/sunny day. So I'm hopeful.
Thats good to know! thanks.

Someone should integrate solar into center speaker grill/mesh. And have it trickle charge all the time.
 

Sponsored

HyperionMark

Well-Known Member
First Name
Mark
Joined
Apr 22, 2022
Threads
14
Messages
416
Reaction score
358
Location
South Dakota
Vehicles
R1T and Model Y (previously a 3 and X)
I just did my first test through the OBD and virtually no vampire drain during a 2 and a half day span. And measured about 1.6 kWh from the wall to run the tender. Let's call that a savings of about half of overall electricity.
 

HyperionMark

Well-Known Member
First Name
Mark
Joined
Apr 22, 2022
Threads
14
Messages
416
Reaction score
358
Location
South Dakota
Vehicles
R1T and Model Y (previously a 3 and X)
I just did my first test through the OBD and virtually no vampire drain during a 2 and a half day span. And measured about 1.6 kWh from the wall to run the tender. Let's call that a savings of about half of overall electricity.
 

DayTripping

Well-Known Member
First Name
Timothy
Joined
Sep 12, 2024
Threads
13
Messages
1,544
Reaction score
2,133
Location
DFW
Vehicles
Gen1 R1T QM, S Plaid, Highland 3 Perf, 3 Long Range, R2 on order
Occupation
Consultant
The solar might be a great option. Anyone calculate if we'd really need the 30w one or would the 20w version work?
 

gultin

Well-Known Member
First Name
S
Joined
Sep 30, 2021
Threads
13
Messages
230
Reaction score
354
Location
CO
Vehicles
R1T
The solar might be a great option. Anyone calculate if we'd really need the 30w one or would the 20w version work?
I debated the 20W vs 30W and went with 30W, assuming that Rivian's 12V power draw is higher than the typical modern ICE vehicle, for which most folks seem to be happy with 20W.

Still early testing for me, but the 30W panel appears to be charging the 12V even on cloudy or partly sunny days.
 

DayTripping

Well-Known Member
First Name
Timothy
Joined
Sep 12, 2024
Threads
13
Messages
1,544
Reaction score
2,133
Location
DFW
Vehicles
Gen1 R1T QM, S Plaid, Highland 3 Perf, 3 Long Range, R2 on order
Occupation
Consultant
I was planning on leaving it in the truck all the time so the size is something I wanted to consider. Here are the sizes for reference of the Suner Power solar cells.

30W - 18.9"L x 15.3"W x 0.15"H = 289 sq in
20W - 15.9"L x 13.1"W x 0.12"H = 208 sq in

So basically, the 30W is almost 6" wider if you flip the orientation. Its width is about the same as the 20W's length, and then comparing the other dimension it is 5.8" longer.

If I can get by with a smaller one, it would be easier to stow it in the truck. I am going to mock up a piece of cardboard and see if the 30W is at all unwieldy.
Sponsored

 
 








Top