Dacia Spring / Renault K-ZE ( CMFA-EV platform )

The Dacia Spring Electric (27.4kWh) / Renault K-ZE (26.8kWh), are both vehicles in the CMFA-EV platform.

There are also a few Chinese EVs that also share the same CMFA-EV battery platform, all the following models are compatible with the Battery-Emulator integration:

• Dacia Spring Electric (2021–present)
• Renault City K-ZE (2019–present)
• Dongfeng Aeolus EX1 (2019–2021)
• Dongfeng Fengxing T1 (2019–2021)
• Dongfeng Fengguang E1 (2019–2024)
• Dongfeng Nano Box (2022–2024)
• Venucia e30 (2019–2023)

Note on model year

Some 2024+ batteries seem to not respond to CAN. Investigation ongoing!

2024+ can be identified with an additional "Pressure Sensor" near the HV/LV connector

General info

These batteries have 72 cells in series, which creates an operating voltage of approximately 216 to 302VDC. Make sure the inverter you are planning to use is compatible with this voltage range!

Testing the battery

In order to read the informations from the BMS, you need:

• LiLyGo T-CAN485 with Battery Emulator installed and configured for this battery and NO inverter.
• 12V source for LilyGo and battery (it can be a Gel battery, UPS, 12V adapter etc)
• Low Voltage battery Connector with those wires connected: 12V, GND, CAN-L and CAN-H (see the connections)

Shopping list

Here is a detailed shopping list for this battery implementation.

Software configuration

For this battery type, use the option called "CMFA platform, 27kWh battery" under the "Battery Protocol" section, NMC chemistry.

Battery module - BMS pin diagram.

BMS reads from each module the cells voltage + one GND and 2 temp sensors (one for each module). should be ~17Kohm range

Wiring diagram, Low Voltage

The battery contains a terminating resistor. The LV connector on the battery has the following pinout:

The pin numbering is engraved on the LV connector (PT06A-12-10S)

Try to source at least the LV connector; scrapers are happy to cut the cables and usually give them for free. The LV connector usually goes to scrap with the car.

Get the HV connector too; it makes things look nicer. Search for HV cable and connector on eBay, part#: 297A21306R

Connect the battery to the Battery-Emulator according to this diagram:

12V power info: The preacharge+contactors consume 1.5A. The BMS itself uses 0.1A

Use a relay board (NO) (5V or 12V) to apply GND to the pins (pin 2AE / 2AD / 2AC all accept a GND signal to be toggled on).

See 4ch SSR on DIN rail (DC-CN)

Wiring, High voltage

The battery has a service disconnect switch:

Note that there are two versions of the service disconnect switch. The 2021 model is different to 2022+. So, if you purchase a service disconnect switch, make sure you get the correct model year!

The polarity of the High Voltage outputs can be seen here, Left is positive, Right is negative.

HV Cable preparation

Beware of the the mantle strings (cut them) = not to touch the copper conductor. The optional ferrule for the copper conductor is 35smm

Configuring the software

Enable the CMFA platform, 27 kWh battery option in the software

Do NOT use PWM contactor control.

Spring keeps the HV voltage between 218V (0% SOC) and 304V (100% SOC) You can adjust SOC min percentage and SOC max percentage from the emulator settings to keep the battery voltage somewhere in the above voltage range. Like -5 / 85 with current build (june 2025)

This battery also benefits from automated 30s daily resets, like the Nissan LEAF platform. This can be automated with BMS power output.

Fuse sizing:

For fuse sizing, we use the max inverter power / 218V = max fuse size. ex, for a 5kW inverter: 5000W / 218V = 23A => use a 25A fuse

Completed builds:

DIY wooden support, with space for the fuse underneath

Note on missing cellvoltages

If you are not seeing all 72 cells in the cellmonitor page, the fuses on the celltaps might be damaged. Telltale sign is that some values get corrupted and charge current goes to 0. This can be repaired by opening the battery, and repairing the damaged traces.