Dual Battery Isolator?

[Emplehod]

We are doing a custom audio installation on a 2021 Model Y dual-motor and want to use two 12-volt batteries using a dual-battery isolator. This is not the relays that some use for isolating batteries. This will have the original output to the 12-volt battery provide input to the isolator and then split the charging to both batteries. The second battery will have the audio amplifier so no additional draw will be on the original battery. The batteries are truly isolated and are never connected.

Question: Are there any special precautions necessary to remove the 12-volt cable (positive) from the existing battery to perform the wiring?

 

[ATPMSD]

Question: Are there any special precautions necessary to remove the 12-volt cable (positive) from the existing battery to perform the wiring?

Yes!

You can search for YouTube videos on battery replacements to see what you need do. But here is a summary;

1. Open the Frunk, if this is where the battery is located
2. Open the car door and power off the car from the main screen, do not close the door. Wait 5-minutes
3. Disconnect the High Voltage Disconnect. I believe is it behind the passenger seat in the Model Y or maybe in the Frunk? (check YouTube)
4. Disconnect the NEGATIVE wire first, then the positive

When reattaching

1. Reconnect the high voltage disconnect
2. Then the positive terminal
3. Then the negative terminal. Try to connect the negative terminal quickly to avoid an arc

 

[ATPMSD]

BTW, unless you have taken the time to fully understand how the 12v system works in a Tesla, do not do this. The system is very different from how ICE cars operate, and so is the battery. You may also void the car warranty. Just a word to the wise.

 

[Emplehod]

Is this High Voltage Disconnect a connector? Bolted terminal?

 

[ATPMSD]

Is this High Voltage Disconnect a connector? Bolted terminal?

Just a plug and soclet connection.

 

[TonyUsa]

We are doing a custom audio installation on a 2021 Model Y dual-motor and want to use two 12-volt batteries using a dual-battery isolator. This is not the relays that some use for isolating batteries. This will have the original output to the 12-volt battery provide input to the isolator and then split the charging to both batteries. The second battery will have the audio amplifier so no additional draw will be on the original battery. The batteries are truly isolated and are never connected.

Question: Are there any special precautions necessary to remove the 12-volt cable (positive) from the existing battery to perform the wiring?

Hello,
I am about to put the audio system in Model 3 2019 also but came across with battery problem. From my understanding that the OEM is lead acid but some site indicated as AGM. Lead acid can not mix with AGM or lithium secondary battery due to the charging system in the Tesla. And now ohmmu lithium battery put the this battery on hold due to the error message.
Which battery are you using? Any problem? How many amps are you running? I am going to run 4-5 amps and I'm sure that I need secondary battery.

 

[jcanoe]

Hello,
I am about to put the audio system in Model 3 2019 also but came across with battery problem. From my understanding that the OEM is lead acid but some site indicated as AGM. Lead acid can not mix with AGM or lithium secondary battery due to the charging system in the Tesla. And now ohmmu lithium battery put the this battery on hold due to the error message.
Which battery are you using? Any problem? How many amps are you running? I am going to run 4-5 amps and I'm sure that I need secondary battery.

The 12V battery in the 2019 Model 3 is a maintenance free (MF) sealed flooded lead-acid battery. It looks like an AGM battery but it is not.

 

[ZroEmit]

Doing the same here in a Model 3 using a Victron Energy Argofet battery isolator. Any issues with the 12v system post install?

 

[TonyUsa]

Doing the same here in a Model 3 using a Victron Energy Argofet battery isolator. Any issues with the 12v system post install?

Are you using lead acid or AGM battery for secondary battery?

 

[TonyUsa]

We are doing a custom audio installation on a 2021 Model Y dual-motor and want to use two 12-volt batteries using a dual-battery isolator. This is not the relays that some use for isolating batteries. This will have the original output to the 12-volt battery provide input to the isolator and then split the charging to both batteries. The second battery will have the audio amplifier so no additional draw will be on the original battery. The batteries are truly isolated and are never connected.

Question: Are there any special precautions necessary to remove the 12-volt cable (positive) from the existing battery to perform the wiring?

Did you get it done? Any problem?