Battery: Volvo XC40 Polestar 2
Caution
Working with high voltage is dangerous. Always follow local laws and regulations regarding high voltage work. If you are unsure about the rules in your country, consult a licensed electrician for more information.
The following batteries are supported:
- 78kWh Volvo XC40 - Recharge, 2021-
- 78kWh Polestar 2 - Long range, 2020- ,2021-, 2022-, 2023-
Connect HVIL2_EXT_IN and HVIL2_EXT_OUT together with a cable. (this will close the HVIL loop in BECM)
The BECM has no built in 120ohm resistor. (BECM = Battery Energy Control Module) Make sure the terminating resistors are correct. CAN networks should have two 120 Ohm resistors in each end of the network. With everything OFF, you can measure resistance between CAN-H and CAN-L. The result should be 60 Ohm.
Attached below are pictures of the BMS pinout. Connect the pins to the LilyGo and 12V supply like this:
- Pin 42 to LilyGo CAN - H
- Pin 43 to LilyGo CAN - L
- Pin 24 & 33 to +12V
- Pin 47 This wire needs to be connected to the battery casing
- Pin 48 GND
To use the CAN contactors on Volvo XC40 and Polestar2, you need to connect the GND from the battery connector (PIN47) to the battery case. This GND is used for insulation monitoring. Without it, the battery will not be able to check the insulation integrity and will not engage contactors.
You must use a DC-DC converter (which you can purchase from the link below) and connect it to the high-voltage output from the front motor. If you skip this step and try to start the battery directly, an irreversible error will occur. After this error, you won't be able to engage the contactor via the CAN bus anymore.
Incase your battery is missing some wires/disconnect switches, here are the OEM part numbers and purchase links. Do note that it might be cheaper to source from your local scrapyard!
| Product | Purchase Link |
|---|---|
| Service disconnect switch XXXXXX | XXXXXX |
| Low voltage 48pin connector | Aliexpress |
| DC DC | Aliexpress |
Make sure that the settings in the USER_SETTINGS.h file are correct. The line:
#define VOLVO_SPA_BATTERY
Needs to be uncommented for the software to interface correctly with the battery.
Next step is then to select the inverter protocol that you intend to use. After setting this up, press compile and upload to the board!
This feature was introduced in 8.1.0